General Relativity: Geometry Meets Physics
Thomsen, Dietrick E.
1975-01-01
Observing the relationship of general relativity and the geometry of space-time, the author questions whether the rest of physics has geometrical explanations. As a partial answer he discusses current research on subatomic particles employing geometric transformations, and cites the existence of geometrical definitions of physical quantities such…
International Nuclear Information System (INIS)
Kenyon, I.R.
1990-01-01
General relativity is discussed in this book at a level appropriate to undergraduate students of physics and astronomy. It describes concepts and experimental results, and provides a succinct account of the formalism. A brief review of special relativity is followed by a discussion of the equivalence principle and its implications. Other topics covered include the concepts of curvature and the Schwarzschild metric, test of the general theory, black holes and their properties, gravitational radiation and methods for its detection, the impact of general relativity on cosmology, and the continuing search for a quantum theory of gravity. (author)
DEFF Research Database (Denmark)
Strøbæk, Pernille Solveig; Willert, Søren
2014-01-01
Following George Herbert Mead, we contend that work-related organizational behavior requires continued negotiation of meaning – using linguistic, behavioral, and social tools. The meaning structures of the Generalized Other(s) of a particular employing organization provide the regulatory framewor...
Straumann, Norbert
2013-01-01
This book provides a completely revised and expanded version of the previous classic edition ‘General Relativity and Relativistic Astrophysics’. In Part I the foundations of general relativity are thoroughly developed, while Part II is devoted to tests of general relativity and many of its applications. Binary pulsars – our best laboratories for general relativity – are studied in considerable detail. An introduction to gravitational lensing theory is included as well, so as to make the current literature on the subject accessible to readers. Considerable attention is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel’s proof of his uniqueness theorem, and a derivation of the basic laws of black hole physics. Part II ends with Witten’s proof of the positive energy theorem, which is presented in detail, together with the required tools on spin structures and spinor analysis. In Part III, all of the differential geomet...
International Nuclear Information System (INIS)
Gourgoulhon, Eric
2013-01-01
The author proposes a course on general relativity. He first presents a geometrical framework by addressing, presenting and discussion the following notions: the relativistic space-time, the metric tensor, Universe lines, observers, principle of equivalence and geodesics. In the next part, he addresses gravitational fields with spherical symmetry: presentation of the Schwarzschild metrics, radial light geodesics, gravitational spectral shift (Einstein effect), orbitals of material objects, photon trajectories. The next parts address the Einstein equation, black holes, gravitational waves, and cosmological solutions. Appendices propose a discussion of the relationship between relativity and GPS, some problems and their solutions, and Sage codes
The Solar System According to General Relativity: The Sun's Space Breaking Meets the Asteroid Strip
Directory of Open Access Journals (Sweden)
Borissova L.
2010-04-01
Full Text Available This study deals with the exact solution of Einstein’s field equations for a sphere of incompressible liquid without the additional limitation initially introduced in 1916 by Schwarzschild, by which the space-time metric must have no singularities. The ob- tained exact solution is then applied to the Universe, the Sun, and the planets, by the assumption that these objects can be approximated as spheres of incompressible liq- uid. It is shown that gravitational collapse of such a sphere is permitted for an object whose characteristics (mass, density, and size are close to the Universe. Meanwhile, there is a spatial break associated with any of the mentioned stellar objects: the break is determined as the approaching to infinity of one of the spatial components of the metric tensor. In particular, the break of the Sun’s space meets the Asteroid strip, while Jupiter’s space break meets the Asteroid strip from the outer side. Also, the space breaks of Mercury, Venus, Earth, and Mars are located inside the Asteroid strip (inside the Sun’s space break.
Sedimentation-related meetings
The sedimentation committee would like to provide information on several meetings that took place in October 1983.The second annual meeting of the American Geomorphological Field Group was organized by S. Wells and T. Gardner and held in Chaco Canyon, N. Mex., October 7-10. Field excursions included visits to instrumented watersheds in badland areas, examination of the Quaternary history of Chaco Canyon, and investigation of fluvial problems associated with uranium mine tailings disposal and coal reclamation.
Wald, Robert M.
2005-01-01
This Resource Letter provides some guidance on issues that arise in teaching general relativity at both the undergraduate and graduate levels. Particular emphasis is placed on strategies for presenting the mathematical material needed for the formulation of general relativity.
Ridgely, Charles T.
2010-01-01
Many textbooks dealing with general relativity do not demonstrate the derivation of forces in enough detail. The analyses presented herein demonstrate straightforward methods for computing forces by way of general relativity. Covariant divergence of the stress-energy-momentum tensor is used to derive a general expression of the force experienced…
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 4. General Theory of Relativity – The Power of Speculative Thought. Asit Banerjee. General Article Volume 11 Issue 4 April 2006 pp 45-55. Fulltext. Click here to view fulltext PDF. Permanent link:
General relativity and experiment
Damour, T.
1994-01-01
The confrontation between Einstein's theory of gravitation and experiment is summarized. Although all current experimental data are compatible with general relativity, the importance of pursuing the quest for possible deviations from Einstein's theory is emphasized.
Jackson, A. T.
1973-01-01
Reviews theoretical and experimental fundamentals of Einstein's theory of general relativity. Indicates that recent development of the theory of the continually expanding universe may lead to revision of the space-time continuum of the finite and unbounded universe. (CC)
General meeting of the Pension Fund
CERN Pension Fund
2010-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Council Room on Monday 6 September 2010 from 14:00 to 16:30 p.m. The Agenda comprises: Opening Remarks - F. Ferrini Presentation of the 2009 Financial Statements - T. Economou Copies of the 2009 Financial Statements are available from Departmental Secretariats. Management Update - T. Economou Report by the Chairman of the Pension Fund Governing Board - F. Ferrini Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to the Secretariat of the Pension Fund. Conclusions - F. Ferrini As usual, participants are invited to drinks after the Meeting. NB\tThe minutes of the 2009 General Meeting are available from the Administration of the Fund (tel. + 41 22 767 27 42 ; e-mail Barbara.Brugger@cern.ch)
Ray, J. R.
1982-01-01
Two theories of matter in general relativity, the fluid theory and the kinetic theory, were studied. Results include: (1) a discussion of various methods of completing the fluid equations; (2) a method of constructing charged general relativistic solutions in kinetic theory; and (3) a proof and discussion of the incompatibility of perfect fluid solutions in anisotropic cosmologies. Interpretations of NASA gravitational experiments using the above mentioned results were started. Two papers were prepared for publications based on this work.
Lectures on general relativity
Papapetrou, Achille
1974-01-01
This book is an elaboration of lecture notes for the graduate course on General Rela tivity given by the author at Boston University in the spring semester of 1972. It is an introduction to the subject only, as the time available for the course was limited. The author of an introduction to General Relativity is faced from the beginning with the difficult task of choosing which material to include. A general criterion as sisting in this choice is provided by the didactic character of the book: Those chapters have to be included in priority, which will be most useful to the reader in enabling him to understand the methods used in General Relativity, the results obtained so far and possibly the problems still to be solved. This criterion is not sufficient to ensure a unique choice. General Relativity has developed to such a degree, that it is impossible to include in an introductory textbook of a reasonable length even a very condensed treatment of all important problems which have been discussed unt...
General Relativity and Gravitation
Ashtekar, Abhay; Berger, Beverly; Isenberg, James; MacCallum, Malcolm
2015-07-01
Part I. Einstein's Triumph: 1. 100 years of general relativity George F. R. Ellis; 2. Was Einstein right? Clifford M. Will; 3. Cosmology David Wands, Misao Sasaki, Eiichiro Komatsu, Roy Maartens and Malcolm A. H. MacCallum; 4. Relativistic astrophysics Peter Schneider, Ramesh Narayan, Jeffrey E. McClintock, Peter Mészáros and Martin J. Rees; Part II. New Window on the Universe: 5. Receiving gravitational waves Beverly K. Berger, Karsten Danzmann, Gabriela Gonzalez, Andrea Lommen, Guido Mueller, Albrecht Rüdiger and William Joseph Weber; 6. Sources of gravitational waves. Theory and observations Alessandra Buonanno and B. S. Sathyaprakash; Part III. Gravity is Geometry, After All: 7. Probing strong field gravity through numerical simulations Frans Pretorius, Matthew W. Choptuik and Luis Lehner; 8. The initial value problem of general relativity and its implications Gregory J. Galloway, Pengzi Miao and Richard Schoen; 9. Global behavior of solutions to Einstein's equations Stefanos Aretakis, James Isenberg, Vincent Moncrief and Igor Rodnianski; Part IV. Beyond Einstein: 10. Quantum fields in curved space-times Stefan Hollands and Robert M. Wald; 11. From general relativity to quantum gravity Abhay Ashtekar, Martin Reuter and Carlo Rovelli; 12. Quantum gravity via unification Henriette Elvang and Gary T. Horowitz.
General Meeting of the Pension Fund
HR Department
2008-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Main Auditorium on Wednesday 22 October 2008 at 14:15 hrs The Agenda comprises: Opening Remarks (F. Ferrini) Results and presentation of the Annual Report 2007 and impact on the Fund of the recent evolution of financial markets (C. Cuénoud) Copies of the 2007 Report are available from departmental secretariats. Activity report of the new Governance of the Pension Fund (F. Ferrini, D. Duret) Questions from members and beneficiaries People wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund.Conclusions (F. Ferrini) As usual, participants are invited to drinks after the Meeting. NB The minutes of the 2007 General Meeting are available from the Administration of the Fund (tel. (+ 41 22) 767 27 42; e-mail mailto:Barbara.Bordjah@cern.ch)
General Meeting Of The Pension Fund
HR Department
2009-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Council Chamber on Wednesday 9 September 2009 from 14:00 to 16:30 p.m. The Agenda comprises: 1.\tOpening Remarks - F. Ferrini 2.\tResults and presentation of the Annual Report 2008. - C. Cuénoud Recent evolution of financial markets. 2009-2010 work plan - T. Economou. Copies of the 2008 Report are available from Departmental secretariats. 3.\tReport on funding policy and principles of the Pension Fund: Working Group 2 Report. - F. Ferrini 4.\tQuestions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to the Secretariat of the Pension Fund. 5.\tConclusions - F. Ferrini As usual, participants are invited to drinks after the meeting. NB\tThe minutes of the 2008 General Meeting are available from the Administration of the Fund (tel. + 41 22 767 27 42 ; e-mail mailto:Sevda.Budun-Kocaturk@cern.ch
General meeting of the Pension Fund
HR Department
2009-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Council Room on Wednesday 9 September 2009 from 14:00 to 16:30 p.m. The Agenda comprises: 1.\tOpening Remarks - F. Ferrini 2.\tResults and presentation of the Annual Report 2008. - C. Cuénoud Recent evolution of financial markets. 2009-2010 work plan - T. Economou. Copies of the 2008 Report are available from departmental secretariats. 3.\tReport on Funding policy and principles of the Pension Fund: Working Group 2 Report. - F. Ferrini 4.\tQuestions from members or beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to the secretariat of the Pension Fund. 5.\tConclusions - F. Ferrini As usual, participants are invited to drinks after the Meeting. NB\tThe minutes of the 2008 General Meeting are available from the Administration of the Fund (tel. + 41 22 767 27 42 ; e-mail mailto:Sevda.Budun-Kocaturk@cern.ch)
General meeting of the Pension Fund
HR Department
2009-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Council Room on Wednesday 9 September 2009 from 14:00 to 16:30 p.m. The Agenda comprises: 1.\tOpening Remarks - F. Ferrini 2.\tResults and presentation of the Annual Report 2008. - C. Cuénoud Recent evolution of financial markets. 2009-2010 work plan - T. Economou. Copies of the 2008 Report are available from departmental secretariats. 3.\tReport on Funding policy and principles of the Pension Fund: Working Group 2 Report. - F. Ferrini 4.\tQuestions from members or beneficiaries Persons wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to the secretariat of the Pension Fund. 5.\tConclusions - F. Ferrini As usual, participants are invited to drinks after the Meeting. NB\tThe minutes of the 2008 General Meeting are available from the Administration of the Fund (tel. + 41 22 767 27 42 ; e-mail mailto:Sevda.Budun-Kocaturk@cern.ch
Annual General Meeting of the Pension Fund
2006-01-01
Annual General Meeting to be held in the CERN Main Auditorium on Wednesday 1st November 2006 at 2.00 p.m. The Agenda will be as follows: Opening Remarks - F. Ferrini Results and presentation of the 2005 Annual Report- Future challenges associated with asset-liability modelling and asset allocation Copies of the 2005 Annual Report are available from departmental secretariats. - C. Cuénoud Recent development of the actuarial position of the Pension Fund - J.-P. Matheys Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them in writing in advance, where possible, and addressed to the Fund Administrator Mr C. Cuénoud. Conclusions - F. Ferrini As usual, participants are invited to drinks after the meeting. NB The minutes of the 2005 AGM are available from the Administration of the Fund: Tel: (+4122) 767 27 42 e-mail: Sophia.Revol@cern.ch)
Annual General Meeting of the Pension Fund
2006-01-01
Annual General Meeting to be held in the CERN Main Auditorium on Wednesday 1st November 2006 at 2.00 p.m. The Agenda will be as follows: Opening Remarks - F. Ferrini Results and presentation of the 2005 Annual Report- Future challenges associated with asset-liability modelling and asset allocation Copies of the 2005 Annual Report are available from departmental secretariats. - C. Cuénoud Recent development of the actuarial position of the Pension Fund - J.-P. Matheys Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them in writing in advance, where possible, addressed to the Fund's Administrator, Mr C. Cuénoud. Conclusions - F. Ferrini As usual, participants are invited to drinks after the meeting. NB The minutes of the 2005 AGM are available from the Administration of the Fund: Tel: (+4122) 767 27 42 e-mail: Sophia.Revol@cern.ch)
General Meeting of the Pension Fund
HR Department
2008-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meetingto be held in the CERN Main Auditorium on Wednesday 22 October 2008 at 14:00 hrs The Agenda comprises: Opening Remarks (F. Ferrini) Results and presentation of the Annual Report 2007 and impact on the Fund of the recent evolution of financial markets (C. Cuénoud) Copies of the 2007 Report are available from departmental secretariats. Activity report of the new Governance of the Pension Fund (F. Ferrini, D. Duret) Questions from members and beneficiaries People wishing to ask questions are encouraged to submit them, where possible, in writing in advance, addressed to Mr C. Cuénoud, Administrator of the Fund. Conclusions (F. Ferrini). As usual, participants are invited to drinks after the meeting. NB\tThe minutes of the 2007 General Meeting are available from the Administration of the Fund (tel. (+ 41 22) 767 27 42; e-mail Barbara.Bordjah@cern.ch)
Introduction to general relativity
Parthasarthy, R
2016-01-01
INTRODUCTION TO GENERAL RELATIVITY begins with a description of the geometry of curved space, explaining geodesics, parallel transport, covariant differentiation, geodesic deviation and spacetime symmetry by killing vectors. It then introduces Einstein's theory of gravitation followed by Schwarzschild solution with its relevance to Positive Mass theorem. The three tests for Einstein's gravity are explained. Other exact solutions such as Vaidya, Kerr and Reisner - Nordstrom metric are included. In the Chapter on cosmological solutions, a detailed description of Godel metric is provided. It then introduces five dimensional spacetime of Kaluza showing the unification of gravity with electromagnetism. This is extended to include non-Abelian gauge theory by invoking compact extra dimensions. Explicit expressions in this case for Christoffel connections and ricci tensor are derived and the higher dimensional gravity action is shown to compactification are given.
Annual General Meeting of the Pension Fund
2006-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Main Auditoriumon Wednesday 1st November 2006 at 2.00 p.m. The Agenda will be as follows: Opening Remarks - F. Ferrini Results and presentation of the 2005 Annual Report- Future challenges associated with asset-liability modelling and asset allocation Copies of the 2005 Annual Report are available from departmental secretariats. - C. Cuénoud Recent development of the actuarial position of the Pension Fund - J.-P. Matheys Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them in writing in advance, where possible, and addressed to the Fund Administrator Mr C. Cuénoud. Conclusions - F. Ferrini As usual, participants are invited to drinks after the meeting. NB: The minutes of the 2005 AGM are available from the Administration of the Fund: Tel: (+4122) 767 27 42 e-mail: Sophia.Revol@cern.ch)
Annual general meeting of the pension fund
2006-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual General Meeting to be held in the CERN Main Auditorium on Wednesday 1st November 2006 at 2.00 p.m. The Agenda will be as follows: Opening Remarks - F. Ferrini Results and presentation of the 2005 Annual Report- Future challenges associated with asset-liability modelling and asset allocation - C. Cuénoud Copies of the 2005 Annual Report are available from Departmental secretariats. Recent development of the actuarial position of the Pension Fund - J.-P. Matheys Questions from members and beneficiaries Persons wishing to ask questions are encouraged to submit them in writing in advance, where possible, to the Fund's Administrator, Mr C. Cuénoud. Conclusions - F. Ferrini As usual, participants are invited to ayttend a drink after the meeting. NB: The minutes of the 2005 AGM are available from the Administration of the Fund: Tel: +41 22 767 27 42, e-mail: Sophia.Revol@cern.ch).
Ashrafian, Hutan
2018-03-01
Several temporal paradoxes exist in physics. These include General Relativity's grandfather and ontological paradoxes and Special Relativity's Langevin-Einstein twin-paradox. General relativity paradoxes can exist due to a Gödel universe that follows Gödel's closed timelike curves solution to Einstein's field equations. A novel biological temporal paradox of General Relativity is proposed based on reproductive biology's phenomenon of heteropaternal fecundation. Herein, dizygotic twins from two different fathers are the result of concomitant fertilization during one menstrual cycle. In this case an Oedipus-like individual exposed to a Gödel closed timelike curve would sire a child during his maternal fertilization cycle. As a consequence of heteropaternal superfecundation, he would father his own dizygotic twin and would therefore generate a new class of autofraternal superfecundation, and by doing so creating a 'twin-father' temporal paradox. Copyright © 2017 Elsevier Ltd. All rights reserved.
Annual Information Meeting of the Pension Fund (General Meeting)
2012-01-01
All members and beneficiaries of the Pension Fund are invited to attend the Annual Information Meeting to be held in the CERN Council Chamber on Wednesday 12 September 2012 from 10 am to 12 pm * Coffee and croissants will be served prior to the meeting as of 9:30 am. *
Conformally Coupled General Relativity
Arbuzov, Andrej; Latosh, Boris
2018-02-01
Gravity model developed in the series of papers \\cite{Arbuzov:2009zza,Arbuzov:2010fz,Pervushin:2011gz} is revisited. Model is based on Ogievetsky theorem that specifies structure of general coordinate transformation group. The theorem is implemented in the context of Noether theorem with the use of nonlinear representation technique. Canonical quantization is performed with the use of reparametrization-invariant time and ADM foliation techniques. Basic quantum features of the models are discussed. Mistakes occurred in the previous papers are corrected.
Directory of Open Access Journals (Sweden)
Bahram Mashhoon
2014-12-01
Full Text Available A brief account of the present status of the recent nonlocal generalization of Einstein’s theory of gravitation is presented. The main physical assumptions that underlie this theory are described. We clarify the physical meaning and significance of Weitzenböck’s torsion and emphasize its intimate relationship with the gravitational field, characterized by the Riemannian curvature of spacetime. In this theory, nonlocality can simulate dark matter; in fact, in the Newtonian regime, we recover the phenomenological Tohline–Kuhn approach to modified gravity. To account for the observational data regarding dark matter, nonlocality is associated with a characteristic length scale of order 1 kpc. The confrontation of nonlocal gravity with observation is briefly discussed.
Stauffer, Frederic R.
1984-01-01
Proposes novel methods of solving mechanics and dynamics problems by changing frames of reference. Uses these ideas to pursue Einstein's notions of inertial and uniformly rotating reference frames, gravitational and inertial mass, and the gravitational bending of light in relation to the simple original problem. (JM)
Introduction to the general relativity
International Nuclear Information System (INIS)
Radix, J.C.
1994-01-01
This work deals with the introduction of the general relativity including the introduction of the tensorial calculation, the Euclidean space in curvilinear coordinates, the Riemann space, the recalls and complements of the restricted relativity and the elements of the general relativity. (O.L.) 83 figs., 3 tabs
General relativity basics and beyond
Date, Ghanashyam
2015-01-01
A Broad Perspective on the Theory of General Relativity and Its Observable Implications General Relativity: Basics and Beyond familiarizes students and beginning researchers with the basic features of the theory of general relativity as well as some of its more advanced aspects. Employing the pedagogical style of a textbook, it includes essential ideas and just enough background material needed for readers to appreciate the issues and current research. Basics The first five chapters form the core of an introductory course on general relativity. The author traces Einstein’s arguments and presents examples of space-times corresponding to different types of gravitational fields. He discusses the adaptation of dynamics in a Riemannian geometry framework, the Einstein equation and its elementary properties, and different phenomena predicted or influenced by general relativity. Beyond Moving on to more sophisticated features of general relativity, the book presents the physical requirements of a well-defined de...
English Book Club - Annual General Meeting
2012-01-01
Wednesday 16 January at 5.30 p.m. In the Clubs barracks by entrance A, CERN building 564. Agenda: 1/ Election of the Chairman of the Meeting 2/ President’s report on 2012 Activities 3/ Treasurer's Report 4/ Nomination for renewal of committee members for 2013 5/ Any Other Business
Johannsen, Tim
2015-01-01
General relativity has been widely tested in weak gravitational fields but still stands largely untested in the strong-field regime. According to the no-hair theorem, black holes in general relativity depend only on their masses and spins and are described by the Kerr metric. Mass and spin are the first two multipole moments of the Kerr spacetime and completely determine all higher-order moments. The no-hair theorem and, hence, general relativity can be tested by measuring potential deviation...
Spinning fluids in general relativity
Ray, J. R.; Smalley, L. L.
1982-01-01
General relativity field equations are employed to examine a continuous medium with internal spin. A variational principle formerly applied in the special relativity case is extended to the general relativity case, using a tetrad to express the spin density and the four-velocity of the fluid. An energy-momentum tensor is subsequently defined for a spinning fluid. The equations of motion of the fluid are suggested to be useful in analytical studies of galaxies, for anisotropic Bianchi universes, and for turbulent eddies.
General relativity and gravitational waves
Weber, Johanna
1961-01-01
An internationally famous physicist and electrical engineer, the author of this text was a pioneer in the investigation of gravitational waves. Joseph Weber's General Relativity and Gravitational Waves offers a classic treatment of the subject. Appropriate for upper-level undergraduates and graduate students, this text remains ever relevant. Brief but thorough in its introduction to the foundations of general relativity, it also examines the elements of Riemannian geometry and tensor calculus applicable to this field.Approximately a quarter of the contents explores theoretical and experimenta
General relativity 50 years old
1966-01-01
In May 1916, 'The Foundations of General Relativity Theory' by Albert Einstein was published in 'Annalen der Physik'. Fifty years later, this major contribution to scientific thought still has a rather isolated position with respect to the main-stream of scientific theory. (In contrast, the Special Theory of Relativity is one of the cornerstones of sub-nuclear physics.) To mark the anniversary of the publication of Einstein's paper a theoretician from CERN discusses the theory and its present status.
Modified General Relativity and Cosmology
Abdel-Rahman, A.-M. M.
1997-10-01
Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter- dominated model with the neoclassical cosmological tests is demonstrated.
Cosmological models in general relativity
Indian Academy of Sciences (India)
Cosmological models in general relativity. B B PAUL. Department of Physics, Nowgong College, Nagaon, Assam, India. MS received 4 October 2002; revised 6 March 2003; accepted 21 May 2003. Abstract. LRS Bianchi type-I space-time filled with perfect fluid is considered here with deceler- ation parameter as variable.
Dimensional Analysis and General Relativity
Lovatt, Ian
2009-01-01
Newton's law of gravitation is a central topic in the first-year physics curriculum. A lecturer can go beyond the physical details and use the history of gravitation to discuss the development of scientific ideas; unfortunately, the most recent chapter in this history, general relativity, is not covered in first-year courses. This paper discusses…
Special relativity, electrodynamics, and general relativity from Newton to Einstein
Kogut, John B
2018-01-01
Special Relativity, Electrodynamics and General Relativity: From Newton to Einstein, Second Edition, is intended to teach (astro)physics, astronomy, and cosmology students how to think about special and general relativity in a fundamental, but accessible, way. Designed to render any reader a "master of relativity," everything on the subject is comprehensible and derivable from first principles. The book emphasizes problem solving, contains abundant problem sets, and is conveniently organized to meet the needs of both student and instructor. Fully revised, updated and expanded second edition Includes new chapters on magnetism as a consequence of relativity and electromagnetism Contains many improved and more engaging figures Uses less algebra resulting in more efficient derivations Enlarged discussion of dynamics and the relativistic version of Newton's second law
The genesis of general relativity
Norton, John; Renn, Jürgen; Sauer, Tilman; Stachel, John
2007-01-01
This four-volume work represents the most comprehensive documentation and study of the creation of general relativity; one of the fundamental physical theories of the 20th century. It comprises key sources from Einstein and others who from the late 19th to the early 20th century contributed to this monumental development. Some of these sources are presented here in translation for the first time. Einstein’s famous Zurich notebook, which documents the pivotal steps toward general relativity, is reproduced here for the first time and transcribed in its entirety. The volumes offer detailed commentaries and analyses of these sources that are based on a close reading of these documents supplemented by interpretations by the leading historians of relativity. All in all, the facets of this work, based on more than a decade of research, combine to constitute one of the most in-depth studies of a scientific revolution ever written.
Testing general relativity on accelerators
Directory of Open Access Journals (Sweden)
Tigran Kalaydzhyan
2015-11-01
Full Text Available Within the general theory of relativity, the curvature of spacetime is related to the energy and momentum of the present matter and radiation. One of the more specific predictions of general relativity is the deflection of light and particle trajectories in the gravitational field of massive objects. Bending angles for electromagnetic waves and light in particular were measured with a high precision. However, the effect of gravity on relativistic massive particles was never studied experimentally. Here we propose and analyze experiments devoted to that purpose. We demonstrate a high sensitivity of the laser Compton scattering at high energy accelerators to the effects of gravity. The main observable – maximal energy of the scattered photons – would experience a significant shift in the ambient gravitational field even for otherwise negligible violation of the equivalence principle. We confirm predictions of general relativity for ultrarelativistic electrons of energy of tens of GeV at a current level of resolution and expect our work to be a starting point of further high-precision studies on current and future accelerators, such as PETRA, European XFEL and ILC.
The Genesis of General Relativity
Renn, Jürgen
2008-09-01
This brief historical review of the genesis of general relativity is based on a detailed study and reconstruction of the historical sources undertaken in a collaborative research project centered at the Max Planck Institute for the History of Science in Berlin. This research was made possible due to a close cooperation between historians of science and physicists. The results of this research are now published in a four-volume work "The Genesis of General Relativity" aiming at a comprehensive account of the way in which the work of Albert Einstein and his contemporaries changed our understanding of space, time, and gravitation. These volumes document the results of a joint effort - extending over more than a decade- at an in-depth analysis of a scientific revolution...
General Relativity and Spacetime Relationism.
Hoefer, Carl
1992-01-01
This dissertation takes up the project of showing that, in the context of the general theory of relativity (GTR), spacetime relationism is not a refuted or hopeless view, as many in the recent literature have maintained (John Earman, Michael Friedman, and others). Most of the challenges to the relationist view in General Relativity can be satisfactorily answered; in addition, the opposing absolutist and substantivalist views of spacetime can be shown to be problematic. The crucial burden for relationists concerned with GTR is to show that the realistic cosmological models, i.e. those that may be roughly accurate representations of our universe, satisfy Mach's ideas about the origin of inertia. This dissertation clears the way for and begins such a demonstration. After a brief discussion of the problem of the nature of spacetime and its history in the Introduction, chapters 2 and 3 provide conceptual analysis and criticism of contemporary philosophical arguments about relationism, absolutism, and particularly substantivalism. The current best arguments in favor of substantivalism are shown to be flawed, with the exception of the argument from inertial and metrical structure; and on this issue, it is shown that both relationism and substantivalism need to argue for modifications of GTR (restriction of its models to those with certain features) in order to have a non-trivial explanation of inertial and metrical structure. For relationists, a Machian account of the origin of inertia in some models of GTR is required. Chapter 4 demonstrates that such a Machian account is equivalent to the demand for a truly general relativity of motion. Chapter 5 explores the history of Einstein's commitment to Mach's ideas in his work on GTR. Through an examination of the history of Einstein's attempts to impose Machian constraints on the models of General Relativity, further insight into the nature of this problem is obtained, as are reasons to believe that the project is by no means
Gravitation. [Book on general relativity
Misner, C. W.; Thorne, K. S.; Wheeler, J. A.
1973-01-01
This textbook on gravitation physics (Einstein's general relativity or geometrodynamics) is designed for a rigorous full-year course at the graduate level. The material is presented in two parallel tracks in an attempt to divide key physical ideas from more complex enrichment material to be selected at the discretion of the reader or teacher. The full book is intended to provide competence relative to the laws of physics in flat space-time, Einstein's geometric framework for physics, applications with pulsars and neutron stars, cosmology, the Schwarzschild geometry and gravitational collapse, gravitational waves, experimental tests of Einstein's theory, and mathematical concepts of differential geometry.
Results from Numerical General Relativity
Baker, John G.
2011-01-01
For several years numerical simulations have been revealing the details of general relativity's predictions for the dynamical interactions of merging black holes. I will review what has been learned of the rich phenomenology of these mergers and the resulting gravitational wave signatures. These wave forms provide a potentially observable record of the powerful astronomical events, a central target of gravitational wave astronomy. Asymmetric radiation can produce a thrust on the system which may accelerate the single black hole resulting from the merger to high relative velocity.
Modern Canonical Quantum General Relativity
Thiemann, Thomas
2008-11-01
Preface; Notation and conventions; Introduction; Part I. Classical Foundations, Interpretation and the Canonical Quantisation Programme: 1. Classical Hamiltonian formulation of general relativity; 2. The problem of time, locality and the interpretation of quantum mechanics; 3. The programme of canonical quantisation; 4. The new canonical variables of Ashtekar for general relativity; Part II. Foundations of Modern Canonical Quantum General Relativity: 5. Introduction; 6. Step I: the holonomy-flux algebra [P]; 7. Step II: quantum-algebra; 8. Step III: representation theory of [A]; 9. Step IV: 1. Implementation and solution of the kinematical constraints; 10. Step V: 2. Implementation and solution of the Hamiltonian constraint; 11. Step VI: semiclassical analysis; Part III. Physical Applications: 12. Extension to standard matter; 13. Kinematical geometrical operators; 14. Spin foam models; 15. Quantum black hole physics; 16. Applications to particle physics and quantum cosmology; 17. Loop quantum gravity phenomenology; Part IV. Mathematical Tools and their Connection to Physics: 18. Tools from general topology; 19. Differential, Riemannian, symplectic and complex geometry; 20. Semianalytical category; 21. Elements of fibre bundle theory; 22. Holonomies on non-trivial fibre bundles; 23. Geometric quantisation; 24. The Dirac algorithm for field theories with constraints; 25. Tools from measure theory; 26. Elementary introduction to Gel'fand theory for Abelean C* algebras; 27. Bohr compactification of the real line; 28. Operatir -algebras and spectral theorem; 29. Refined algebraic quantisation (RAQ) and direct integral decomposition (DID); 30. Basics of harmonic analysis on compact Lie groups; 31. Spin network functions for SU(2); 32. + Functional analytical description of classical connection dynamics; Bibliography; Index.
Introduction on the 2nd annual general meeting of ARCCNM
International Nuclear Information System (INIS)
Zhao Jun; He Zuoxiang; Dang Yaping
2003-01-01
This paper outlines general information on the 2nd annual general meeting of ARCCNM (Asian Regional Cooperative Council for Nuclear Medicine). The international symposium exchanged new development recently on basic and clinical nuclear medicine. Asian school of nuclear medicine is an educational enterprise of ARCCNM, and the objective is to organize and coordinate academic and training programs in nuclear medicine. It will promote nuclear medicine in Asia region through enhancing regional scientific activities and research collaboration
Einstein algebras and general relativity
International Nuclear Information System (INIS)
Heller, M.
1992-01-01
A purely algebraic structure called an Einstein algebra is defined in such a way that every spacetime satisfying Einstein's equations is an Einstein algebra but not vice versa. The Gelfand representation of Einstein algebras is defined, and two of its subrepresentations are discussed. One of them is equivalent to the global formulation of the standard theory of general relativity; the other one leads to a more general theory of gravitation which, in particular, includes so-called regular singularities. In order to include other types of singularities one must change to sheaves of Einstein algebras. They are defined and briefly discussed. As a test of the proposed method, the sheaf of Einstein algebras corresponding to the space-time of a straight cosmic string with quasiregular singularity is constructed. 22 refs
Stochastic quantization in general relativity
International Nuclear Information System (INIS)
Rumpf, H.
1985-01-01
The stochastic quantization method of Parisi and Wu is briefly reviewed stressing its formal resemblance to the Einstein-Smoluchowski theory of Brownian motion. In order to make it applicable in the context of General Relativity, we present a generalization of the method to the case of Lorentzian signature of the space-time metric. It is shown that this approach has non-trivial implications even for linear quantum fields in curved space-time, where it introduces preferred quantum states characterized by the analyticity of the Feynman propagator in the mass parameter. Finally we propose a stochastic quantization scheme for the full nonlinear Einstein theory of gravitation. It employs the concept of a metric in field configuration space and is based mathematically on Ito's calculus. Non-trivial implications for the gravitational path integral measure and for perturbation theory are pointed out. (Author)
Homothetic motions in general relativity
International Nuclear Information System (INIS)
McIntosh, C.B.G.
1976-01-01
Properties of homothetic or self-similar motions in general relativity are examined with particular reference to vacuum and perfect-fluid space-times. The role of the homothetic bivector with components Hsub((a;b)) formed from the homothetic vector H is discussed in some detail. It is proved that a vacuum space-time only admits a nontrivial homothetic motion if the homothetic vector field is non-null and is not hypersurface orthogonal. As a subcase of a more general result it is shown that a perfect-fluid space-time cannot admit a non-trivial homothetic vector which is orthogonal to the fluid velocity 4-vector. (author)
Nonlinear generalization of special relativity
International Nuclear Information System (INIS)
Winterberg, F.
1985-01-01
In Poincares axiomatic formulation special relativity is a derived consequence of a true Lorentz contraction, for a rod in absolute motion through a substratum. Furthermore, Lorentz had shown that the rod contraction can be understood by an inverse square law interaction and therefore special relativity derived from more fundamental principles. The derivation by Lorentz shows that the root of the divergence problems is the singular inverse square law. By replacing the inverse square law with a regular one through the introduction of a finite length, the author has succeeded in deriving a nonlinear generalization of special relativity which eliminates all infinities. Besides the relative velocities, these nonlinear transformation equations also contain absolute velocities against a substratum, but in the limit of small energies they go over into the linear Lorentz transformations. Depending on the smallness of the fundamental length, departures from special relativity can be observed only at very high energies. The theorem that the velocity of light is the same in all reference systems still holds and likewise the conservation laws for energy and momentum
Achieving Speaker Gender Equity at the American Society for Microbiology General Meeting.
Casadevall, Arturo
2015-08-04
In 2015, the American Society for Microbiology (ASM) General Meeting essentially achieved gender equity, with 48.5% of the oral presentations being given by women. The mechanisms associated with increased female participation were (i) making the Program Committee aware of gender statistics, (ii) increasing female representation among session convener teams, and (iii) direct instruction to try to avoid all-male sessions. The experience with the ASM General Meeting shows that it is possible to increase the participation of female speakers in a relatively short time and suggests concrete steps that may be taken to achieve this at other meetings. Public speaking is very important for academic advancement in science. Historically women have been underrepresented as speakers in many scientific meetings. This article describes concrete steps that were associated with achieving gender equity at a major meeting. Copyright © 2015 Casadevall.
Relativity: Special, General, and Cosmological
International Nuclear Information System (INIS)
Ellis, G F R
2005-01-01
Wolfgang Rindler is known as a writer of exceptional clarity. This quality is evident in this book as it explores in depth first special relativity, then general relativity, and finally relativistic cosmology. He bases his writing in the fundamental underlying ideas and principles that so successfully guided Einstein in his work, clarifying their nature and implications in an illuminating way with many examples. The usual suspects are there: the relativity principle and equivalence principle, the abolishing of absolute space, invariance of the speed of light, analytic and geometric representations of the Lorentz transformation, its kinematic and dynamic consequences, relativistic optics, Minkowski spacetime, energy and momentum conservation, and the Compton effect. Particularly useful is the emphasis on the unity of the whole: for example (p 63) that the kinematic effect of length shortening must imply a corresponding detailed mechanical explanation of that shortening. The tensor formulation of Maxwell's equations leads to the transformation properties of the electromagnetic field and consequent elegant derivation of the field of an infinite straight current; in this case, relativity is important even for slowly moving charges because an ordinary current moves a very big charge (p 151). General relativity is systematically introduced in stages, starting with curved spaces and moving on through static and stationary spacetimes, geodesics, and tensor calculus to the field equations. A considerable strength of the book is the careful detailed examination of the local and global geometry of the major significant solutions of the equations: the Schwarzschild spacetime and its Kruskal extension, plane gravitational waves, de sitter and anti-de Sitter spacetimes, and Robertson-Walker cosmologies. The latter includes a clear presentation of the dust and radiation model dynamics for the variety of possible cases, a detailed examination of observational relations, and
IAEA Director General encouraged by meeting on Iran
International Nuclear Information System (INIS)
2006-01-01
Full text: IAEA Director General Mohamed ElBaradei welcomes the high-level meeting between Foreign Ministers of the EU3, the High Representative of the EU and Supreme National Security Council (SNSC) Secretary Ali Larijani scheduled to take place tomorrow in Vienna. 'I urge all parties to use this opportunity to create the necessary conditions to return to negotiations,' Dr. ElBaradei said. 'I call on Iran to demonstrate full transparency toward the IAEA to resolve important outstanding issues related to its nuclear programme. I also call on Iran to take all the necessary confidence building measures required to assure the international community of the peaceful nature of its nuclear programme,' he said. 'As the negotiations proceed, it will be essential for all parties to specifically address the security, political and economic issues that underlie any future comprehensive settlement.' 'Only through these two tracks - full transparency on the part of Iran and negotiations with all concerned parties - can confidence be established regarding the nature of Iran's nuclear programme and a durable solution be found,' Dr. ElBaradei said. (IAEA)
Spacecraft Tests of General Relativity
Anderson, John D.
1997-01-01
Current spacecraft tests of general relativity depend on coherent radio tracking referred to atomic frequency standards at the ground stations. This paper addresses the possibility of improved tests using essentially the current system, but with the added possibility of a space-borne atomic clock. Outside of the obvious measurement of the gravitational frequency shift of the spacecraft clock, a successor to the suborbital flight of a Scout D rocket in 1976 (GP-A Project), other metric tests would benefit most directly by a possible improved sensitivity for the reduced coherent data. For purposes of illustration, two possible missions are discussed. The first is a highly eccentric Earth orbiter, and the second a solar-conjunction experiment to measure the Shapiro time delay using coherent Doppler data instead of the conventional ranging modulation.
Geometric quantization and general relativity
International Nuclear Information System (INIS)
Souriau, J.-M.
1977-01-01
The purpose of geometric quantization is to give a rigorous mathematical content to the 'correspondence principle' between classical and quantum mechanics. The main tools are borrowed on one hand from differential geometry and topology (differential manifolds, differential forms, fiber bundles, homology and cohomology, homotopy), on the other hand from analysis (functions of positive type, infinite dimensional group representations, pseudo-differential operators). Some satisfactory results have been obtained in the study of dynamical systems, but some fundamental questions are still waiting for an answer. The 'geometric quantization of fields', where some further well known difficulties arise, is still in a preliminary stage. In particular, the geometric quantization on the gravitational field is still a mere project. The situation is even more uncertain due to the fact that there is no experimental evidence of any quantum gravitational effect which could give us a hint towards what we are supposed to look for. The first level of both Quantum Theory, and General Relativity describes passive matter: influence by the field without being a source of it (first quantization and equivalence principle respectively). In both cases this is only an approximation (matter is always a source). But this approximation turns out to be the least uncertain part of the description, because on one hand the first quantization avoids the problems of renormalization and on the other hand the equivalence principle does not imply any choice of field equations (it is known that one can modify Einstein equations at short distances without changing their geometrical properties). (Auth.)
Ninth ITER negotiations meeting (N-9) and related meetings
International Nuclear Information System (INIS)
Luo Delong
2003-01-01
The Ninth ITER Negotiations Meeting (N-9) was held on 9-10 November 2003 at the Fragrant Hill Golden Resources Commerce Hotel in Beijing. China hosted this meeting. Delegations from Canada, China, the European Union, Japan, the Republic of Korea, the Russian Federation and the United States of America, as well as members from the International Team, met to continue their efforts to reach agreement on the implementation of the ITER international fusion energy research project. Delegates discussed a full range of legal, technical, administrative and managerial topics, including the form and the structure of the International Organization, staffing, resources, and risk management, which will form the basis for the Agreement on implementing ITER and the operation of the International ITER Organization
Modern Canonical Quantum General Relativity;
Energy Technology Data Exchange (ETDEWEB)
Kiefer, Claus [Institute for Theoretical Physics, Universitaet zu Koeln, Zuelpicher Strasse 77, 50937 Cologne (Germany)
2008-06-21
The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches-loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang-Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to the geometrical nature of gravity, no such background exists in quantum gravity. Instead, the notion of a background is supposed to emerge a posteriori as an approximate notion from quantum states of geometry. As a consequence, the standard ultraviolet
Zorn algebra in general relativity
International Nuclear Information System (INIS)
Oliveira, C.G.; Maia, M.D.
The covariant differential properties of the split Cayley subalgebra of local real quaternion tetrads is considered. Referred to this local quaternion tetrad several geometrical objects are given in terms of Zorn-Weyl matrices. Associated to a pair of real null vectors we define two-component spinor fields over the curved space and the associated Zorn-Weyl matrices which satisfy the Dirac equation written in terms of the Zorn algebra. The formalism is generalized by considering a field of complex tetrads defining a Hermitian second rank tensor. The real part of this tensor describes the gravitational potentials and the imaginary part the electromagnetic potentials in the Lorentz gauge. The motion of a charged spin zero test body is considered. The Zorn-Weyl algebra associated to this generalized formalism has elements belonging to the full octonion algebra [pt
77 FR 63839 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2012-10-17
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide...) Virus Monovalent Vaccine manufactured by GlaxoSmithKline. On November 15, 2012, the committee will meet...
Numerical Hydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2000-05-01
Full Text Available The current status of numerical solutions for the equations of ideal general relativistic hydrodynamics is reviewed. Different formulations of the equations are presented, with special mention of conservative and hyperbolic formulations well-adapted to advanced numerical methods. A representative sample of available numerical schemes is discussed and particular emphasis is paid to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. A comprehensive summary of relevant astrophysical simulations in strong gravitational fields, including gravitational collapse, accretion onto black holes and evolution of neutron stars, is also presented.
Quantum General Relativity, Torsion and Uncertainty Relations
de Sabbata, V.; Sivaram, C.; Borzeszkowski, H.-H. V.; Treder, H.-J.
It is shown that in gravitational theories with torsion one is led to commutation rules corresponding to Landau-Peierls type uncertainty relations.Translated AbstractQuantisierte allgemeine Relativitätstheorie, Torsion und UnschärferelationenEs wird gezeigt, daß man in Gravitationstheorien mit Torsion zu Vertauschungsregeln geführt wird, die Landau-Peierls-artigen Unschärferelationen entsprechen.
Numerical Hydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2003-01-01
Full Text Available The current status of numerical solutions for the equations of ideal general relativistic hydrodynamics is reviewed. With respect to an earlier version of the article, the present update provides additional information on numerical schemes, and extends the discussion of astrophysical simulations in general relativistic hydrodynamics. Different formulations of the equations are presented, with special mention of conservative and hyperbolic formulations well-adapted to advanced numerical methods. A large sample of available numerical schemes is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. A comprehensive summary of astrophysical simulations in strong gravitational fields is presented. These include gravitational collapse, accretion onto black holes, and hydrodynamical evolutions of neutron stars. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances on the formulation of the gravitational field and hydrodynamic equations and the numerical methodology designed to solve them.
General relativity and relativistic astrophysics. Second edition
International Nuclear Information System (INIS)
Straumann, N.
1984-01-01
This book discusses general relativity and relativistic astrophysics. It is written in three parts. Part I develops the mathematical tools used in the general theory of relativity, Part II develops the general theory of relativity along traditional lines, and Part III treats aspects of the physics of compact objects
Stochastic quantization of general relativity
International Nuclear Information System (INIS)
Rumpf, H.
1986-01-01
Following an elementary exposition of the basic mathematical concepts used in the theory of stochastic relaxation processes the stochastic quantization method of Parisi and Wu is briefly reviewed. The method is applied to Einstein's theory of gravitation using a formalism that is manifestly covariant with respect to field redefinitions. This requires the adoption of Ito's calculus and the introduction of a metric in field configuration space, for which there is a unique candidate. Due to the indefiniteness of the Euclidean Einstein-Hilbert action stochastic quantization is generalized to the pseudo-Riemannian case. It is formally shown to imply the DeWitt path integral measure. Finally a new type of perturbation theory is developed. (Author)
Testing General Relativity Using Gravitational-Wave Observations
Indian Academy of Sciences (India)
Testing General Relativity Using Gravitational-Wave. Observations. Parameswaran Ajith ICTS-TIFR, Bangalore. On behalf of the LIGO Scientific Collaboration and. Virgo Collaboration. 27th Mid-Year Meeting of the Indian Academy of Sciences. 1 July 2016, IISc Bangalore. LIGO-G1601410-v2 indig ...
A logic road from special relativity to general relativity
Andréka, Hajnal; Madarász, Judit X.; Németi, István; Székely, Gergely
2010-01-01
We present a streamlined axiom system of special relativity in first-order logic. From this axiom system we "derive" an axiom system of general relativity in two natural steps. We will also see how the axioms of special relativity transform into those of general relativity. This way we hope to make general relativity more accessible for the non-specialist.
Conformal methods in general relativity
Valiente Kroon, Juan A
2016-01-01
This book offers a systematic exposition of conformal methods and how they can be used to study the global properties of solutions to the equations of Einstein's theory of gravity. It shows that combining these ideas with differential geometry can elucidate the existence and stability of the basic solutions of the theory. Introducing the differential geometric, spinorial and PDE background required to gain a deep understanding of conformal methods, this text provides an accessible account of key results in mathematical relativity over the last thirty years, including the stability of de Sitter and Minkowski spacetimes. For graduate students and researchers, this self-contained account includes useful visual models to help the reader grasp abstract concepts and a list of further reading, making this the perfect reference companion on the topic.
Pulsar timing and general relativity
Backer, D. C.; Hellings, R. W.
1986-01-01
Techniques are described for accounting for relativistic effects in the analysis of pulsar signals. Design features of instrumentation used to achieve millisecond accuracy in the signal measurements are discussed. The accuracy of the data permits modeling the pulsar physical characteristics from the natural glitches in the emissions. Relativistic corrections are defined for adjusting for differences between the pulsar motion in its spacetime coordinate system relative to the terrestrial coordinate system, the earth's motion, and the gravitational potentials of solar system bodies. Modifications of the model to allow for a binary pulsar system are outlined, including treatment of the system as a point mass. Finally, a quadrupole model is presented for gravitational radiation and techniques are defined for using pulsars in the search for gravitational waves.
General relativity and mathematics; Relatividad General y Matematicas
Energy Technology Data Exchange (ETDEWEB)
Mars, M.
2015-07-01
General relativity is more than a theory of gravity, since any physical process occupies space and lasts for a time, forcing to reconcile that physical theory that describes what the dynamic nature of space-time itself. (Author)
Centennial of general relativity a celebration
2017-01-01
It has been over 100 years since the presentation of the Theory of General Relativity by Albert Einstein, in its final formulation, to the Royal Prussian Academy of Sciences. To celebrate 100 years of general relativity, World Scientific publishes this volume with a dual goal: to assess the current status of the field of general relativity in broad terms, and discuss future directions. The volume thus consists of broad overviews summarizing major developments over the past decades and their perspective contributions.
Conformal Hamiltonian dynamics of general relativity
Energy Technology Data Exchange (ETDEWEB)
Arbuzov, A.B.; Barbashov, B.M. [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Nazmitdinov, R.G. [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Department de Fisica, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Pervushin, V.N., E-mail: pervush@theor.jinr.r [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Borowiec, A. [Institute of Theoretical Physics, University of Wroclaw, Pl. Maxa Borna 9, 50-204 Wroclaw (Poland); Pichugin, K.N. [Kirensky Institute of Physics, 660036 Krasnoyarsk (Russian Federation); Zakharov, A.F. [Institute of Theoretical and Experimental Physics, B. Cheremushkinskaya str. 25, 117259 Moscow (Russian Federation)
2010-08-09
The General Relativity formulated with the aid of the spin connection coefficients is considered in the finite space geometry of similarity with the Dirac scalar dilaton. We show that the redshift evolution of the General Relativity describes the vacuum creation of the matter in the empty Universe at the electroweak epoch and the dilaton vacuum energy plays a role of the dark energy.
Black hole dynamics in general relativity
Indian Academy of Sciences (India)
Black hole dynamics in general relativity ... Basic features of dynamical black holes in full, non-linear general relativity are summarized in a pedagogical fashion. ... Institute for Gravitational Physics and Geometry, Physics Department, Penn State University, University Park, PA 16802, USA; Institute for Theoretical Physics, ...
General Relativity in (1 + 1) Dimensions
Boozer, A. D.
2008-01-01
We describe a theory of gravity in (1 + 1) dimensions that can be thought of as a toy model of general relativity. The theory should be a useful pedagogical tool, because it is mathematically much simpler than general relativity but shares much of the same conceptual structure; in particular, it gives a simple illustration of how gravity arises…
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
We review the experimental evidence for Einstein's general relativity. Tests of the Einstein equivalence principle support the postulates of curved space-time and bound variations of fundamental constants in space and time, while solar system experiments strongly confirm weak-field general relativity. The binary pulsar ...
Dynamics of relative motion of test particles in general relativity
International Nuclear Information System (INIS)
Bazanski, S.L.
1977-01-01
Several variational principles which lead to the first and the second geodesic deviation equations, recently formulated by the author and used for the description of the relative motion of test particles in general relativity are presented. Relations between these principles are investigated and exhibited. The Hamilton-Jacobi equation is also studied for these generalized deviations and the conservation laws appearing here are discussed
The Confrontation between General Relativity and Experiment
Directory of Open Access Journals (Sweden)
Will Clifford
2001-01-01
Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analysing them are reviewed. Einstein's equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Future tests of EEP and of the inverse square law will search for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected in an amount that agrees with general relativity to half a percent using the Hulse-Taylor binary pulsar, and new binary pulsar systems may yield further improvements.When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.
O(3)-invariant tunneling in general relativity
International Nuclear Information System (INIS)
Berezin, V.A.; Tkachev, I.I.; Kuzmin, V.A.; AN SSSR, Moscow. Inst. Yadernykh Issledovanij)
1987-12-01
We derived a general formula for the action for any O(3)-invariant tunneling processes in false vacuum decay in general relativity. The general classification of the bubble Euclidean trajectories is elaborated and explicit expressions for bounces for some processes like the vacuum creation of a double bubble, in particular in the vicinity of a black hole; the subbarrier creation of the Einstein-Rosen bridge, creation from nothing of two Minkowski worlds connected by a shell etc., are given. (orig.)
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
Yet modern developments in particle theory suggest that it is probably not the entire story and that modification of the basic theory may be required at some level. String theory generally predicts a proliferation of scalar fields that could result in alterations of general relativity reminiscent of the Brans–Dicke theory of the 1960s ...
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
Tests of the Einstein equivalence principle support the postulates of curved space-time and bound variations of fundamental constants in space and time, while solar system experiments strongly confirm weak-field general relativity. The binary pulsar provides tests of gravitational wave damping and of strong-field general ...
Field strenght copies in general relativity
International Nuclear Information System (INIS)
Oliveira, C.G.; Letelier, P.S.
Considering the SO(3,1) local, internal, transformations as the gauge group of general relativity, the possibility of having different affine connections (potentials) generating the same internal curvature (field strenght) is studied. Explicit examples of 'copies' are exhibited. The possibility to extend the concept of 'copy' to more general geometries is discussed. (Author) [pt
Einstein and General Relativity: Historical Perspectives.
Chandrasekhar, S.
1979-01-01
This paper presented in the 1978 Oppenheimer Memorial Lecture at Los Alamos Scientific Laboratories on August 17, 1978, discusses Einstein's contributions to physics, in particular, his discovery of the general theory of relativity. (HM)
General relativity, strings, and mathematical physics
Porrati, Massimo
1999-01-01
We give a historical review of some aspects of string theory relevant to our present understanding of general relativity, and connected with Einstein's unification program. We also point out to various mathematical fallouts of $9 string theory. (31 refs).
Black hole dynamics in general relativity
Indian Academy of Sciences (India)
Abstract. Basic features of dynamical black holes in full, non-linear general relativity are summarized in a pedagogical fashion. Qualitative properties of the evolution of various horizons follow directly from the celebrated Raychaudhuri equation.
Initial Value Problem in General Relativity
Isenberg, James
2013-01-01
This article, written to appear as a chapter in "The Springer Handbook of Spacetime", is a review of the initial value problem for Einstein's gravitational field theory in general relativity. Designed to be accessible to graduate students who have taken a first course in general relativity, the article first discusses how to reformulate the spacetime fields and spacetime covariant field equations of Einstein's theory in terms of fields and field equations compatible with a 3+1 foliation of sp...
Towards a Virtual General Meeting: ‘I accept’ or ‘I decline’?
Directory of Open Access Journals (Sweden)
Wanne M. Pemmelaar
2008-12-01
Full Text Available The General Meeting plays an essential role in the functioning of the Dutch corporate governance system which is based on self-regulation. It is therefore of importance that shareholders turn up during the Annual General Meeting (AGM. However, studies conducted in 2007 showed that on average only 45% of shareholders cast their vote during the AGM. Several academic writers have proposed a Virtual General Meeting (VGM as a solution to the low attendance of shareholders. This article is meant to produce some ideas on how the VGM could contribute to corporate governance, the position of the shareholder and to provide some means to measure these contributions. It is argued that in order to measure whether the introduction of the VGM in Dutch business law would be feasible and desirable one needs more than comparative law alone to examine the functionality of a VGM in relation to corporate governance. The Dutch legislature probably cannot escape the fact that it should allow more virtuality into the AGMs in the near future. However, the possible positive and negative effects of the VGM have not yet been proven convincingly. To serve the continuing discussion on a VGM, suggestions are made for two models for the VGM that represent two ends of a spectrum of virtuality and law.
Energy and Uncertainty in General Relativity
Cooperstock, F. I.; Dupre, M. J.
2018-03-01
The issue of energy and its potential localizability in general relativity has challenged physicists for more than a century. Many non-invariant measures were proposed over the years but an invariant measure was never found. We discovered the invariant localized energy measure by expanding the domain of investigation from space to spacetime. We note from relativity that the finiteness of the velocity of propagation of interactions necessarily induces indefiniteness in measurements. This is because the elements of actual physical systems being measured as well as their detectors are characterized by entire four-velocity fields, which necessarily leads to information from a measured system being processed by the detector in a spread of time. General relativity adds additional indefiniteness because of the variation in proper time between elements. The uncertainty is encapsulated in a generalized uncertainty principle, in parallel with that of Heisenberg, which incorporates the localized contribution of gravity to energy. This naturally leads to a generalized uncertainty principle for momentum as well. These generalized forms and the gravitational contribution to localized energy would be expected to be of particular importance in the regimes of ultra-strong gravitational fields. We contrast our invariant spacetime energy measure with the standard 3-space energy measure which is familiar from special relativity, appreciating why general relativity demands a measure in spacetime as opposed to 3-space. We illustrate the misconceptions by certain authors of our approach.
Teaching General Relativity to the Layperson
Egdall, Mark
2009-01-01
This paper describes a lay course on general relativity (GR) given at the Osher Lifelong Learning Institute at Florida International University. It is presented in six hour-and-a-half weekly sessions. Other courses offered by the author include special relativity (which precedes the course described here), quantum theory, and cosmology. Students…
Black hole based tests of general relativity
International Nuclear Information System (INIS)
Yagi, Kent; Stein, Leo C
2016-01-01
General relativity has passed all solar system experiments and neutron star based tests, such as binary pulsar observations, with flying colors. A more exotic arena for testing general relativity is in systems that contain one or more black holes. Black holes are the most compact objects in the Universe, providing probes of the strongest-possible gravitational fields. We are motivated to study strong-field gravity since many theories give large deviations from general relativity only at large field strengths, while recovering the weak-field behavior. In this article, we review how one can probe general relativity and various alternative theories of gravity by using electromagnetic waves from a black hole with an accretion disk, and gravitational waves from black hole binaries. We first review model-independent ways of testing gravity with electromagnetic/gravitational waves from a black hole system. We then focus on selected examples of theories that extend general relativity in rather simple ways. Some important characteristics of general relativity include (but are not limited to) (i) only tensor gravitational degrees of freedom, (ii) the graviton is massless, (iii) no quadratic or higher curvatures in the action, and (iv) the theory is four-dimensional. Altering a characteristic leads to a different extension of general relativity: (i) scalar–tensor theories, (ii) massive gravity theories, (iii) quadratic gravity, and (iv) theories with large extra dimensions. Within each theory, we describe black hole solutions, their properties, and current and projected constraints on each theory using black hole based tests of gravity. We close this review by listing some of the open problems in model-independent tests and within each specific theory. (paper)
A short course in general relativity
Foster, James
1995-01-01
Suitable for a one-semester course in general relativity for senior undergraduate or beginning graduate students, this text clarifies the mathematical aspects of Einstein's general theory of relativity without sacrificing physical understanding. The text begins with an exposition of those aspects of tensor calculus and differential geometry needed for a proper exposition of the subject. The discussion then turns to the spacetime of general relativity and to geodesic motion, comparisons and contrasts with Newton's theory being drawn where appropriate. A brief consideration of the field equations is followed by a discussion of physics in the vicinity of massive objects, including an elementary treatment of black holes. Particular attention is paid to those aspects of the theory that have observational consequences. The book concludes with brief introductory chapters on gravitational radiation and cosmology, and includes an appendix that reviews the special theory of relativity. In preparing this new edition, th...
The Confrontation between General Relativity and Experiment.
Will, Clifford M
2014-01-01
The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein's equivalence principle (EEP) is well supported by experiments such as the Eötvös experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.
Conceptual Relativity Meets Realism in Metaphysics
Czech Academy of Sciences Publication Activity Database
Marvan, Tomáš
2016-01-01
Roč. 12, č. 2 (2016), s. 23-37 E-ISSN 1849-0514 Institutional support: RVO:67985955 Keywords : Hilary Putnam * conceptual relativity * realism * optional languages Subject RIV: AA - Philosophy ; Religion OBOR OECD: Philosophy, History and Philosophy of science and technology https://www.ffri.hr/phil/casopis/content.html
2012-08-03
...] National Poultry Improvement Plan; General Conference Committee Meeting and 41st Biennial Conference AGENCY... notice of a meeting of the General Conference Committee of the National Poultry Improvement Plan (NPIP... CONTACT: Dr. C. Stephen Roney, Senior Coordinator, National Poultry Improvement Plan, VS, APHIS, 1506...
77 FR 1051 - General Conference Committee of the National Poultry Improvement Plan; Meeting
2012-01-09
...] General Conference Committee of the National Poultry Improvement Plan; Meeting AGENCY: Animal and Plant... the General Conference Committee of the National Poultry Improvement Plan. DATES: The meeting will be... INFORMATION CONTACT: Dr. C. Stephen Roney, Senior Coordinator, National Poultry Improvement Plan, VS, APHIS...
2010-05-03
...] National Poultry Improvement Plan; General Conference Committee Meeting and 40th Biennial Conference AGENCY... notice of a meeting of the General Conference Committee of the National Poultry Improvement Plan (NPIP... Coordinator, National Poultry Improvement Plan, VS, APHIS, 1498 Klondike Road, Suite 101, Conyers, GA 30094...
Towards a Virtual General Meeting: ‘I accept’ or ‘I decline’?
Pemmelaar, Wanne M.
2008-01-01
The General Meeting plays an essential role in the functioning of the Dutch corporate governance system which is based on self-regulation. It is therefore of importance that shareholders turn up during the Annual General Meeting (AGM). However, studies conducted in 2007 showed that on average only
Generalized Disjunctions in (Infinitary) Structural Consequence Relations
Czech Academy of Sciences Publication Activity Database
Cintula, Petr; Noguera, C.
2012-01-01
Roč. 18, č. 3 (2012), s. 442-443 ISSN 1079-8986. [Logic Colloquium 2011. 11.07.2011-16.07.2011, Barcelona] R&D Projects: GA MŠk(CZ) 1M0545 Institutional research plan: CEZ:AV0Z10300504 Keywords : Abstract Algebraic Logic * Generalized disjunction * Proof by cases properties * Consequence relations Subject RIV: BA - General Mathematics http://www.math.ucla.edu/~asl/bsl/1803- toc .htm
Behrend, Dirk (Editor); Baver, Karen D. (Editor)
2010-01-01
This volume is the proceedings of the sixth General Meeting of the International VLBI Service for Geodesy and Astrometry (IVS), held in Hobart, Tasmania, Australia, February 7-13, 2010. The contents of this volume also appear on the IVS Web site at http://ivscc.gsfc.nasa.gov/publications/gm2010. The keynote of the sixth GM was the new perspectives of the next generation VLBI system under the theme "VLBI2010: From Vision to Reality". The goal of the meeting was to provide an interesting and informative program for a wide cross-section of IVS members, including station operators, program managers, and analysts. This volume contains 88 papers. All papers were edited by the editors for usage of the English language, form, and minor content-related issues.
Einstein and the history of general relativity
International Nuclear Information System (INIS)
Howard, D.; Stachel, J.
1989-01-01
This book is a collection of essays by the authors and other people that deal with scientific opinions that led Einstein and his contemporaries to their views of general relativity. Some of the essays explore Einstein's passage from the special theory through a sequence of gravitational theories to the discovery of the field equations of the grand theory in November 1915. Two other essays discuss Einstein's public and private exchanges with Max Abraham and Tullio Levi-Civita in 1913 and 1914. A sympathetic picture of H.A. Lorentz's reaction to the general theory of relativity is included, and a careful and insightful essay on the early understanding of the Schwarzschild-Droste solution to the field equations of general relativity is presented. One paper presents a discussion on the state of the enterprise of general relativity between 1925 and 1928, and a short essay details the history of steps toward quantum gravitational through canonical quantization. A discussion of the history of derivations of the geodesic equation of motion from the field equation and conservation laws of the general theory is presented. The early history of geometrical unified field theories is included
Introduction to 2-spinors in general relativity
O'Donnell, Peter
2003-01-01
This book deals with 2-spinors in general relativity, beginning by developing spinors in a geometrical way rather than using representation theory, which can be a little abstract. This gives the reader greater physical intuition into the way in which spinors behave. The book concentrates on the algebra and calculus of spinors connected with curved space-time. Many of the well-known tensor fields in general relativity are shown to have spinor counterparts. An analysis of the Lanczos spinor concludes the book, and some of the techniques so far encountered are applied to this. Exercises play an i
77 FR 42319 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2012-07-18
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide... consideration of the appropriateness of cell lines derived from human tumors for vaccine manufacture. FDA...
78 FR 20663 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2013-04-05
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function..., Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, FDA. FDA intends to...
75 FR 2876 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2010-01-19
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide... virus vaccine for the 2010 - 2011 influenza season. FDA intends to make background material available to...
75 FR 47605 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2010-08-06
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Laboratory of Vector Borne Virus Diseases, Division of Viral Products, Office of Vaccines Research and Review...
78 FR 60884 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2013-10-02
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Immunoregulation, Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics...
76 FR 55397 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2011-09-07
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Laboratory of Method Development, Division of Viral Products, Office of Vaccines Research and Review, Center...
76 FR 44016 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2011-07-22
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Allergenic Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research...
76 FR 13646 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2011-03-14
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Polysaccharides, Division of Bacterial, Parasitic, and Allergenic Products, Office of Vaccines Research and Review...
75 FR 59729 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2010-09-28
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... vaccines for a post-exposure prophylaxis indication using the animal rule. On November 17, 2010, the...
75 FR 17929 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2010-04-08
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide... vaccine manufactured by GlaxoSmithKline and indicated for the prevention of rotavirus gastroenteritis in...
76 FR 3639 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2011-01-20
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide... the influenza virus vaccine for the 2011-2012 influenza season. The committee will also hear an update...
77 FR 3780 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2012-01-25
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug... public. Name of Committee: Vaccines and Related Biological Products Advisory Committee. General Function... Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, FDA. The...
78 FR 5465 - Vaccines and Related Biological Products Advisory Committee; Notice of Meeting
2013-01-25
...] Vaccines and Related Biological Products Advisory Committee; Notice of Meeting AGENCY: Food and Drug...: Vaccines and Related Biological Products Advisory Committee. General Function of the Committee: To provide... virus vaccine for the 2013- 2014 influenza season. FDA intends to make background material available to...
The Confrontation between General Relativity and Experiment
Directory of Open Access Journals (Sweden)
Will Clifford M.
2006-03-01
Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed. Einstein’s equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse-Taylor binary pulsar, and other binary pulsar systems have yielded other tests, especially of strong-field effects. When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.
Relational Coordination in Danish General Practice
DEFF Research Database (Denmark)
Lundstrøm, Sanne Lykke
. The dissertation present the research study and a collection of three research papers prepared during the period from May 2010 to June 2014. Relational coordination and organisational social capital are measures of novel aspects of an organisation's performance. Relational coordination analyse the communication...... and relationship networks through which work is coordinated across functional and organisational boundaries. Previous studies have shown that relational coordination is positively associated with delivery of care for patients with chronic illness. Organisational social capital is used when analysing...... the psychosocial work environment in organisations, and is seen as a powerful resources for improving organisational performance. Relational coordination and organisational social capital may oer new insight and opportunities for general practice to learn. General practice provides cost-efficient, first...
Generating perfect fluid spheres in general relativity
International Nuclear Information System (INIS)
Boonserm, Petarpa; Visser, Matt; Weinfurtner, Silke
2005-01-01
Ever since Karl Schwarzschild's 1916 discovery of the spacetime geometry describing the interior of a particular idealized general relativistic star--a static spherically symmetric blob of fluid with position-independent density--the general relativity community has continued to devote considerable time and energy to understanding the general-relativistic static perfect fluid sphere. Over the last 90 years a tangle of specific perfect fluid spheres has been discovered, with most of these specific examples seemingly independent from each other. To bring some order to this collection, in this article we develop several new transformation theorems that map perfect fluid spheres into perfect fluid spheres. These transformation theorems sometimes lead to unexpected connections between previously known perfect fluid spheres, sometimes lead to new previously unknown perfect fluid spheres, and in general can be used to develop a systematic way of classifying the set of all perfect fluid spheres
Giant pulsar glitches in full general relativity
Sourie, A.; Chamel, N.; Novak, J.; Oertel, M.
2017-12-01
We present recent numerical simulations of giant pulsar glitches, as observed in the emblematic Vela pulsar, based on a two-fluid model, including for the first time all general-relativistic effects and realistic equations of state. In particular, we focus on modelling the vortex-mediated transfer of angular momentum that takes place during the spin-up stage from the neutron superfluid to the charged particles through dissipative mutual friction forces. Taking general relativity into account does not only modify the structure of the star but also leads to a new coupling between the fluids arising from frame-dragging effects. As a consequence, general relativity can strongly affect the global dynamics of pulsar glitches : the errors on the value of the characteristic rise time incurred by using Newtonian gravity are thus found to be as large as ˜ 40 % for the models considered.
A possible calculation of general relativity effects
International Nuclear Information System (INIS)
Gallova, M.; Ryba, M.
1975-01-01
The calculation of tyree basic effects of the general theory of relativity was performed in the so-called isotropic coordinates and by means of line element ds 2 derived by Hood. It was found that the calculation yielded the same expressions as did that performed by Schwarzschild element ds 2 . (author)
The confrontation between general relativity and experiment
Indian Academy of Sciences (India)
Because of its elegance and simplicity, and because of its empirical success, general relativity has become the foundation ... in this section, and for references to the literature, the reader is referred to 'Theory and Experiment in Gravitational Physics' [1] and to the 'living' review article [2]. We end with a discussion of possible ...
Summary of classical general relativity workshop
Indian Academy of Sciences (India)
In the classical general relativity workshop, ten lectures were presented on various topics. The topics included aspects of black-hole physics, gravitational collapse and the formation of black holes, specific stellar models like a superdense star, method of extracting solutions by exploiting Noether symmetry, brane world and.
Gravity: An Introduction to Einstein's General Relativity
International Nuclear Information System (INIS)
Fabris, Julio C
2004-01-01
General relativity is one of the cornerstones of modern physics. In spite of this, the teaching of general relativity at undergraduate level remains quite marginal. The reasons for this particular situation are quite well known. We can quote, for example, two of them: general relativity requires specific mathematical tools that are somehow outside the mainstream of undergraduate technical development; moreover, this is a branch of physics whose observational and experimental applications have remained rare until recent times, and even though this scenario has changed dramatically in the last few years, the new situation has not yet been absorbed into undergraduate teaching. In this new book, Hartle attempts to address the difficulties that must be faced by anyone who teaches general relativity at undergraduate level. In order to not scare the student with the hard technical preparation needed to obtain the basic equations of general relativity, Einstein's equations, he simply gives up the idea of introducing these equations at the very beginning. Instead, he chooses to present Einstein's equations, with most of the mathematics needed to do them, in the last part of the book. This delicate (and of course dangerous) choice has the advantage of introducing the reader first to the physical aspects of general relativity. This approach can be dangerous because the relevant solutions of the equations necessary to discuss the physical content of general relativity are presented first without a formal derivation. The book is divided into three parts. In the first, covering five chapters of the 24 in the whole book, Newtonian physics and special relativity are reviewed. This review is done in a manner that prepares the reader for the subsequent discussion of general relativity itself. The principle of relativity, the variational principle, the geometrical content of Newtonian theory and the main ideas behind special relativity are all presented. The heart of the book is, in
Tests of General Relativity with GW150914.
Abbott, B P; Abbott, R; Abbott, T D; Abernathy, M R; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Adya, V B; Affeldt, C; Agathos, M; Agatsuma, K; Aggarwal, N; Aguiar, O D; Aiello, L; Ain, A; Ajith, P; Allen, B; Allocca, A; Altin, P A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C C; Areeda, J S; Arnaud, N; Arun, K G; Ascenzi, S; Ashton, G; Ast, M; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Babak, S; Bacon, P; Bader, M K M; Baker, P T; Baldaccini, F; Ballardin, G; Ballmer, S W; Barayoga, J C; Barclay, S E; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barta, D; Bartlett, J; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Baune, C; Bavigadda, V; Bazzan, M; Behnke, B; Bejger, M; Bell, A S; Bell, C J; Berger, B K; Bergman, J; Bergmann, G; Berry, C P L; Bersanetti, D; Bertolini, A; Betzwieser, J; Bhagwat, S; Bhandare, R; Bilenko, I A; Billingsley, G; Birch, J; Birney, R; Birnholtz, O; Biscans, S; Bisht, A; Bitossi, M; Biwer, C; Bizouard, M A; Blackburn, J K; Blair, C D; Blair, D G; Blair, R M; Bloemen, S; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bohe, A; Bojtos, P; Bond, C; Bondu, F; Bonnand, R; Boom, B A; Bork, R; Boschi, V; Bose, S; Bouffanais, Y; Bozzi, A; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Brillet, A; Brinkmann, M; Brisson, V; Brockill, P; Brooks, A F; Brown, D A; Brown, D D; Brown, N M; Buchanan, C C; Buikema, A; Bulik, T; Bulten, H J; Buonanno, A; Buskulic, D; Buy, C; Byer, R L; Cadonati, L; Cagnoli, G; Cahillane, C; Calderón Bustillo, J; Callister, T; Calloni, E; Camp, J B; Cannon, K C; Cao, J; Capano, C D; Capocasa, E; Carbognani, F; Caride, S; Casanueva Diaz, J; Casentini, C; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C B; Cerboni Baiardi, L; Cerretani, G; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chan, M; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, H Y; Chen, Y; Cheng, C; Chincarini, A; Chiummo, A; Cho, H S; Cho, M; Chow, J H; Christensen, N; Chu, Q; Chua, S; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P-F; Colla, A; Collette, C G; Cominsky, L; Constancio, M; Conte, A; Conti, L; Cook, D; Corbitt, T R; Cornish, N; Corsi, A; Cortese, S; Costa, C A; Coughlin, M W; Coughlin, S B; Coulon, J-P; Countryman, S T; Couvares, P; Cowan, E E; Coward, D M; Cowart, M J; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Cripe, J; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dal Canton, T; Danilishin, S L; D'Antonio, S; Danzmann, K; Darman, N S; Dattilo, V; Dave, I; Daveloza, H P; Davier, M; Davies, G S; Daw, E J; Day, R; DeBra, D; Debreczeni, G; Degallaix, J; De Laurentis, M; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M C; Di Fiore, L; Di Giovanni, M; Di Lieto, A; Di Pace, S; Di Palma, I; Di Virgilio, A; Dojcinoski, G; Dolique, V; Donovan, F; Dooley, K L; Doravari, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Ducrot, M; Dwyer, S E; Edo, T B; Edwards, M C; Effler, A; Eggenstein, H-B; Ehrens, P; Eichholz, J; Eikenberry, S S; Engels, W; Essick, R C; Etzel, T; Evans, M; Evans, T M; Everett, R; Factourovich, M; Fafone, V; Fair, H; Fairhurst, S; Fan, X; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fays, M; Fehrmann, H; Fejer, M M; Ferrante, I; Ferreira, E C; Ferrini, F; Fidecaro, F; Fiori, I; Fiorucci, D; Fisher, R P; Flaminio, R; Fletcher, M; Fournier, J-D; Franco, S; Frasca, S; Frasconi, F; Frei, Z; Freise, A; Frey, R; Frey, V; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gabbard, H A G; Gair, J R; Gammaitoni, L; Gaonkar, S G; Garufi, F; Gatto, A; Gaur, G; Gehrels, N; Gemme, G; Gendre, B; Genin, E; Gennai, A; George, J; Gergely, L; Germain, V; Ghosh, Abhirup; Ghosh, Archisman; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, K; Glaefke, A; Goetz, E; Goetz, R; Gondan, L; González, G; Gonzalez Castro, J M; Gopakumar, A; Gordon, N A; Gorodetsky, M L; Gossan, S E; Gosselin, M; Gouaty, R; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greco, G; Green, A C; Groot, P; Grote, H; Grunewald, S; Guidi, G M; Guo, X; Gupta, A; Gupta, M K; Gushwa, K E; Gustafson, E K; Gustafson, R; Hacker, J J; Hall, B R; Hall, E D; Hammond, G; Haney, M; Hanke, M M; Hanks, J; Hanna, C; Hannam, M D; Hanson, J; Hardwick, T; Harms, J; Harry, G M; Harry, I W; Hart, M J; Hartman, M T; Haster, C-J; Haughian, K; Healy, J; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Hennig, J; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hodge, K A; Hofman, D; Hollitt, S E; Holt, K; Holz, D E; Hopkins, P; Hosken, D J; Hough, J; Houston, E A; Howell, E J; Hu, Y M; Huang, S; Huerta, E A; Huet, D; Hughey, B; Husa, S; Huttner, S H; Huynh-Dinh, T; Idrisy, A; Indik, N; Ingram, D R; Inta, R; Isa, H N; Isac, J-M; Isi, M; Islas, G; Isogai, T; Iyer, B R; Izumi, K; Jacqmin, T; Jang, H; Jani, K; Jaranowski, P; Jawahar, S; Jiménez-Forteza, F; Johnson, W W; Johnson-McDaniel, N K; Jones, D I; Jones, R; Jonker, R J G; Ju, L; Haris, M K; Kalaghatgi, C V; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karki, S; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, S; Kaur, T; Kawabe, K; Kawazoe, F; Kéfélian, F; Kehl, M S; Keitel, D; Kelley, D B; Kells, W; Kennedy, R; Key, J S; Khalaidovski, A; Khalili, F Y; Khan, I; Khan, S; Khan, Z; Khazanov, E A; Kijbunchoo, N; Kim, C; Kim, J; Kim, K; Kim, Nam-Gyu; Kim, Namjun; Kim, Y-M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Kleybolte, L; Klimenko, S; Koehlenbeck, S M; Kokeyama, K; Koley, S; Kondrashov, V; Kontos, A; Korobko, M; Korth, W Z; Kowalska, I; Kozak, D B; Kringel, V; Krishnan, B; Królak, A; Krueger, C; Kuehn, G; Kumar, P; Kuo, L; Kutynia, A; Lackey, B D; Landry, M; Lange, J; Lantz, B; Lasky, P D; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C H; Lee, H K; Lee, H M; Lee, K; Lenon, A; Leonardi, M; Leong, J R; Leroy, N; Letendre, N; Levin, Y; Levine, B M; Li, T G F; Libson, A; Littenberg, T B; Lockerbie, N A; Logue, J; Lombardi, A L; London, L T; Lord, J E; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J D; Lousto, C O; Lovelace, G; Lück, H; Lundgren, A P; Luo, J; Lynch, R; Ma, Y; MacDonald, T; Machenschalk, B; MacInnis, M; Macleod, D M; Magaña-Sandoval, F; Magee, R M; Mageswaran, M; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Mandel, I; Mandic, V; Mangano, V; Mansell, G L; Manske, M; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A S; Maros, E; Martelli, F; Martellini, L; Martin, I W; Martin, R M; Martynov, D V; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Masso-Reid, M; Matichard, F; Matone, L; Mavalvala, N; Mazumder, N; Mazzolo, G; McCarthy, R; McClelland, D E; McCormick, S; McGuire, S C; McIntyre, G; McIver, J; McManus, D J; McWilliams, S T; Meacher, D; Meadors, G D; Meidam, J; Melatos, A; Mendell, G; Mendoza-Gandara, D; Mercer, R A; Merilh, E; Merzougui, M; Meshkov, S; Messenger, C; Messick, C; Meyers, P M; Mezzani, F; Miao, H; Michel, C; Middleton, H; Mikhailov, E E; Milano, L; Miller, J; Millhouse, M; Minenkov, Y; Ming, J; Mirshekari, S; Mishra, C; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moggi, A; Mohan, M; Mohapatra, S R P; Montani, M; Moore, B C; Moore, C J; Moraru, D; Moreno, G; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, C L; Mueller, G; Muir, A W; Mukherjee, Arunava; Mukherjee, D; Mukherjee, S; Mukund, N; Mullavey, A; Munch, J; Murphy, D J; Murray, P G; Mytidis, A; Nardecchia, I; Naticchioni, L; Nayak, R K; Necula, V; Nedkova, K; Nelemans, G; Neri, M; Neunzert, A; Newton, G; Nguyen, T T; Nielsen, A B; Nissanke, S; Nitz, A; Nocera, F; Nolting, D; Normandin, M E; Nuttall, L K; Oberling, J; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Ohme, F; Oliver, M; Oppermann, P; Oram, Richard J; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Pai, A; Pai, S A; Palamos, J R; Palashov, O; Palomba, C; Pal-Singh, A; Pan, H; Pan, Y; Pankow, C; Pannarale, F; Pant, B C; Paoletti, F; Paoli, A; Papa, M A; Paris, H R; Parker, W; Pascucci, D; Pasqualetti, A; Passaquieti, R; Passuello, D; Patricelli, B; Patrick, Z; Pearlstone, B L; Pedraza, M; Pedurand, R; Pekowsky, L; Pele, A; Penn, S; Perreca, A; Pfeiffer, H P; Phelps, M; Piccinni, O; Pichot, M; Piergiovanni, F; Pierro, V; Pillant, G; Pinard, L; Pinto, I M; Pitkin, M; Poggiani, R; Popolizio, P; Post, A; Powell, J; Prasad, J; Predoi, V; Premachandra, S S; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Pürrer, M; Qi, H; Qin, J; Quetschke, V; Quintero, E A; Quitzow-James, R; Raab, F J; Rabeling, D S; Radkins, H; Raffai, P; Raja, S; Rakhmanov, M; Rapagnani, P; Raymond, V; Razzano, M; Re, V; Read, J; Reed, C M; Regimbau, T; Rei, L; Reid, S; Reitze, D H; Rew, H; Reyes, S D; Ricci, F; Riles, K; Robertson, N A; Robie, R; Robinet, F; Rocchi, A; Rolland, L; Rollins, J G; Roma, V J; Romano, R; Romanov, G; Romie, J H; Rosińska, D; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Sachdev, S; Sadecki, T; Sadeghian, L; Salconi, L; Saleem, M; Salemi, F; Samajdar, A; Sammut, L; Sanchez, E J; Sandberg, V; Sandeen, B; Sanders, J R; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Sauter, O; Savage, R L; Sawadsky, A; Schale, P; Schilling, R; Schmidt, J; Schmidt, P; Schnabel, R; Schofield, R M S; Schönbeck, A; Schreiber, E; Schuette, D; Schutz, B F; Scott, J; Scott, S M; Sellers, D; Sengupta, A S; Sentenac, D; Sequino, V; Sergeev, A; Serna, G; Setyawati, Y; Sevigny, A; Shaddock, D A; Shah, S; Shahriar, M S; Shaltev, M; Shao, Z; Shapiro, B; Shawhan, P; Sheperd, A; Shoemaker, D H; Shoemaker, D M; Siellez, K; Siemens, X; Sigg, D; Silva, A D; Simakov, D; Singer, A; Singer, L P; Singh, A; Singh, R; Singhal, A; Sintes, A M; Slagmolen, B J J; Smith, J R; Smith, N D; Smith, R J E; Son, E J; Sorazu, B; Sorrentino, F; Souradeep, T; Srivastava, A K; Staley, A; Steinke, M; Steinlechner, J; Steinlechner, S; Steinmeyer, D; Stephens, B C; Stone, R; Strain, K A; Straniero, N; Stratta, G; Strauss, N A; Strigin, S; Sturani, R; Stuver, A L; Summerscales, T Z; Sun, L; Sutton, P J; Swinkels, B L; Szczepańczyk, M J; Tacca, M; Talukder, D; Tanner, D B; Tápai, M; Tarabrin, S P; Taracchini, A; Taylor, R; Theeg, T; Thirugnanasambandam, M P; Thomas, E G; Thomas, M; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Tiwari, S; Tiwari, V; Tokmakov, K V; Tomlinson, C; Tonelli, M; Torres, C V; Torrie, C I; Töyrä, D; Travasso, F; Traylor, G; Trifirò, D; Tringali, M C; Trozzo, L; Tse, M; Turconi, M; Tuyenbayev, D; Ugolini, D; Unnikrishnan, C S; Urban, A L; Usman, S A; Vahlbruch, H; Vajente, G; Valdes, G; Vallisneri, M; van Bakel, N; van Beuzekom, M; van den Brand, J F J; Van Den Broeck, C; Vander-Hyde, D C; van der Schaaf, L; van Heijningen, J V; van Veggel, A A; Vardaro, M; Vass, S; Vasúth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Vetrano, F; Viceré, A; Vinciguerra, S; Vine, D J; Vinet, J-Y; Vitale, S; Vo, T; Vocca, H; Vorvick, C; Voss, D; Vousden, W D; Vyatchanin, S P; Wade, A R; Wade, L E; Wade, M; Walker, M; Wallace, L; Walsh, S; Wang, G; Wang, H; Wang, M; Wang, X; Wang, Y; Ward, R L; Warner, J; Was, M; Weaver, B; Wei, L-W; Weinert, M; Weinstein, A J; Weiss, R; Welborn, T; Wen, L; Weßels, P; Westphal, T; Wette, K; Whelan, J T; White, D J; Whiting, B F; Williams, D; Williams, R D; Williamson, A R; Willis, J L; Willke, B; Wimmer, M H; Winkler, W; Wipf, C C; Wittel, H; Woan, G; Worden, J; Wright, J L; Wu, G; Yablon, J; Yam, W; Yamamoto, H; Yancey, C C; Yap, M J; Yu, H; Yvert, M; Zadrożny, A; Zangrando, L; Zanolin, M; Zendri, J-P; Zevin, M; Zhang, F; Zhang, L; Zhang, M; Zhang, Y; Zhao, C; Zhou, M; Zhou, Z; Zhu, X J; Zucker, M E; Zuraw, S E; Zweizig, J; Boyle, M; Campanelli, M; Hemberger, D A; Kidder, L E; Ossokine, S; Scheel, M A; Szilagyi, B; Teukolsky, S; Zlochower, Y
2016-06-03
The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large-velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant's mass and spin, as determined from the low-frequency (inspiral) and high-frequency (postinspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasinormal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parametrized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 10^{13} km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.
General relativity theory and relativistic astrophysics
International Nuclear Information System (INIS)
Straumann, N.
1981-01-01
The topics of the monograph are: differential geometry in general relativity, the equivalence principle, the Einstein field equations, the Schwarzschild solution and classical tests, weak fields, the post-newtonian approximation, neutron stars and rotating black holes and binary X-ray sources. (WL)
Generalization of Gibbs Entropy and Thermodynamic Relation
Park, Jun Chul
2010-01-01
In this paper, we extend Gibbs's approach of quasi-equilibrium thermodynamic processes, and calculate the microscopic expression of entropy for general non-equilibrium thermodynamic processes. Also, we analyze the formal structure of thermodynamic relation in non-equilibrium thermodynamic processes.
General Relativity and John Archibald Wheeler
Ciufolini, Ignazio
2010-01-01
Observational and experimental data pertaining to gravity and cosmology are changing our view of the Universe. General relativity is a fundamental key for the understanding of these observations and its theory is undergoing a continuing enhancement of its intersection with observational and experimental data. These data include direct observations and experiments carried out in our solar system, among which there are direct gravitational wave astronomy, frame dragging and tests of gravitational theories from solar system and spacecraft observations. This book explores John Archibald Wheeler's seminal and enduring contributions in relativistic astrophysics and includes: the General Theory of Relativity and Wheeler's influence; recent developments in the confrontation of relativity with experiments; the theory describing gravitational radiation, and its detection in Earth-based and space-based interferometer detectors as well as in Earth-based bar detectors; the mathematical description of the initial value pro...
Partial Differential Equations in General Relativity
International Nuclear Information System (INIS)
Choquet-Bruhat, Yvonne
2008-01-01
General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)
Partial Differential Equations in General Relativity
Energy Technology Data Exchange (ETDEWEB)
Choquet-Bruhat, Yvonne
2008-09-07
General relativity is a physical theory basic in the modeling of the universe at the large and small scales. Its mathematical formulation, the Einstein partial differential equations, are geometrically simple, but intricate for the analyst, involving both hyperbolic and elliptic PDE, with local and global problems. Many problems remain open though remarkable progress has been made recently towards their solutions. Alan Rendall's book states, in a down-to-earth form, fundamental results used to solve different types of equations. In each case he gives applications to special models as well as to general properties of Einsteinian spacetimes. A chapter on ODE contains, in particular, a detailed discussion of Bianchi spacetimes. A chapter entitled 'Elliptic systems' treats the Einstein constraints. A chapter entitled 'Hyperbolic systems' is followed by a chapter on the Cauchy problem and a chapter 'Global results' which contains recently proved theorems. A chapter is dedicated to the Einstein-Vlasov system, of which the author is a specialist. On the whole, the book surveys, in a concise though precise way, many essential results of recent interest in mathematical general relativity, and it is very clearly written. Each chapter is followed by an up to date bibliography. In conclusion, this book will be a valuable asset to relativists who wish to learn clearly-stated mathematical results and to mathematicians who want to penetrate into the subtleties of general relativity, as a mathematical and physical theory. (book review)
Eighth Negotiators' Standing Sub-Group and related meetings
International Nuclear Information System (INIS)
Rager, J.-P.
2003-01-01
The Max-Planck-Institute for Plasma Physics (IPP) at Garching near Munich was the venue for the eighth meeting of the ITER Negotiators' Standing Sub-Group (NSSG-8) and a number of related meetings over an intensive nine day period of work from 14 to 22 May 2003. The European Union hosted the meeting, which was also attended by delegations from Canada, China, Japan, the Russian Federation (RF) and the USA. This was the first time at the NSSG for the Chinese and US delegations, following their accession to the ITER Negotiations at the previous Negotiators' meeting (N-8) (see ITER ITA Newsletter No. 1, February 2003). Over the course of four days the Working Groups met, at times in parallel sessions, to make progress in their respective topic areas. The work of each group was led by a rapporteur, who subsequently presented the group's findings and recommendations to the NSSG as a whole for consideration and guidance
Dynamics of bubbles in general relativity
International Nuclear Information System (INIS)
Berezin, V.A.; Kuzmin, V.A.; Tkachev, I.I.
1987-01-01
This is a systematic study of the evolution of thin shell bubbles in general relativity. We develop the general thin-wall formalism first elaborated by Israel and apply it to the investigation of the motion of various bubbles arising in the course of phase transitions in the very early Universe including new phase bubbles, old phase remnants, and domains. We consider metric junction conditions and derive constraints both on the decay of metastable states and on the evolution of non- equilibrium scalar field configurations (fluctuations) following from the global geometry of spacetime
The Confrontation between General Relativity and Experiment
Directory of Open Access Journals (Sweden)
Clifford M. Will
2014-06-01
Full Text Available The status of experimental tests of general relativity and of theoretical frameworks for analyzing them is reviewed and updated. Einstein’s equivalence principle (EEP is well supported by experiments such as the Eötvös experiment, tests of local Lorentz invariance and clock experiments. Ongoing tests of EEP and of the inverse square law are searching for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, the Nordtvedt effect in lunar motion, and frame-dragging. Gravitational wave damping has been detected in an amount that agrees with general relativity to better than half a percent using the Hulse–Taylor binary pulsar, and a growing family of other binary pulsar systems is yielding new tests, especially of strong-field effects. Current and future tests of relativity will center on strong gravity and gravitational waves.
General relativity with applications to astrophysics
Straumann, Norbert
2004-01-01
This text provides a comprehensive and timely introduction to general relativity The foundations of the theory in Part I are thoroughly developed together with the required mathematical background from differential geometry in Part III The six chapters in Part II are devoted to tests of general relativity and to many of its applications Binary pulsars are studied in considerable detail Much space is devoted to the study of compact objects, especially to black holes This includes a detailed derivation of the Kerr solution, Israel's proof of his uniqueness theorem, and derivations of the basic laws of black hole physics The final chapter of this part contains Witten's proof of the positive energy theorem The book addresses undergraduate and graduate students in physics, astrophysics and mathematics It is very well structured and should become a standard text for a modern treatment of gravitational physics The clear presentation of differential geometry makes it also useful for string theory and other fields of ...
Interacting electromagnetic waves in general relativity
International Nuclear Information System (INIS)
Griffiths, J.B.
1976-01-01
The problem is considered of finding exact solutions of the Einstein-Maxwell equations which describe the physical situation of two colliding and subsequently interacting electromagnetic waves. The general theory of relativity predicts a nonlinear interaction between electromagnetic waves. The situation is described using an approximate geometrical method, and a new exact solution describing two interacting electromagnetic waves is given. This describes waves emitted from two sources mutually focusing each other on the opposite source. (author)
Testing General Relativity with Pulsar Timing
Directory of Open Access Journals (Sweden)
Stairs Ingrid H.
2003-01-01
Full Text Available Pulsars of very different types, including isolated objects and binaries (with short- and long-period orbits, and white-dwarf and neutron-star companions provide the means to test both the predictions of general relativity and the viability of alternate theories of gravity. This article presents an overview of pulsars, then discusses the current status of and future prospects for tests of equivalence-principle violations and strong-field gravitational experiments.
Screening vector field modifications of general relativity
International Nuclear Information System (INIS)
Beltrán Jiménez, Jose; Delvas Fróes, André Luís; Mota, David F.
2013-01-01
A screening mechanism for conformal vector–tensor modifications of general relativity is proposed. The conformal factor depends on the norm of the vector field and makes the field to vanish in high dense regions, whereas drives it to a non-null value in low density environments. Such process occurs due to a spontaneous symmetry breaking mechanism and gives rise to both the screening of fifth forces as well as Lorentz violations. The cosmology and local constraints are also computed
Mach-Einstein doctrine and general relativity
von Borzeszkowski, H.-H.; Treder, H.-J.
1996-07-01
It is argued that, under the assumption that the strong principle of equivalence holds, the theoretical realization of the Mach principle (in the version of the Mach-Einstein doctrine) and of the principle of general relativity are alternative programs. That means only the former or the latter can be realized—at least as long as only field equations of second order are considered. To demonstrate this we discuss two sufficiently wide classes of theories (Einstein-Grossmann and Einstein-Mayer theories, respectively) both embracing Einstein's theory of general relativity (GRT). GRT is shown to be just that “degenerate case” of the two classes which satisfies the principle of general relativity but not the Mach-Einstein doctrine; in all the other cases one finds an opposite situation. These considerations lead to an interesting “complementarity” between general relativity and Mach-Einstein doctine. In GRT, via Einstein's equations, the covariant and Lorentz-invariant Riemann-Einstein structure of the space-time defines the dynamics of matter: The symmetric matter tensor Ttk is given by variation of the Lorentz-invariant scalar density L mat, and the dynamical equations satisfied by Tik result as a consequence of the Bianchi identities valid for the left-hand side of Einstein's equations. Otherwise, in all other cases, i.e., for the “Mach-Einstein theories” here under consideration, the matter determines the coordinate or reference systems via gravity. In Einstein-Grossmann theories using a holonomic representation of the space-time structure, the coordinates are determined up to affine (i.e. linear) transformations, and in Einstein-Mayer theories based on an anholonomic representation the reference systems (the tetrads) are specified up to global Lorentz transformations. The corresponding conditions on the coordinate and reference systems result from the postulate that the gravitational field is compatible with the strong equivalence of inertial and
Probing the Higgs vacuum with general relativity
Mannheim, Philip D.; Kazanas, Demosthenes
1991-01-01
It is shown that the structure of the Higgs vacuum can be revealed in gravitational experiments which probe the Schwarzschild geometry to only one order in MG/r beyond that needed for the classical tests of general relativity. The possibility that deviations from the conventional geometry are at least theoretically conceivable is explored. The deviations obtained provide a diagnostic test for searching for the existence of macroscopic scalar fields and open up the possiblity for further exploring the Higgs mechanism.
Relativity the special and the general theory
Einstein, Albert
2015-01-01
After completing the final version of his general theory of relativity in November 1915, Albert Einstein wrote a book about relativity for a popular audience. His intention was "to give an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical apparatus of theoretical physics." The book remains one of the most lucid explanations of the special and general theories ever written. In the early 1920s alone, it was translated into ten languages, and fifteen editions in the original German appeared over the course of Einstein's lifetime. This new edition of Einstein's celebrated book features an authoritative English translation of the text along with an introduction and a reading companion by Hanoch Gutfreund and Jürgen Renn that examines the evolution of Einstein's thinking and casts his ideas in a broader present-day context. A special chapter explores the history...
Simple recursion relations for general field theories
International Nuclear Information System (INIS)
Cheung, Clifford; Shen, Chia-Hsien; Trnka, Jaroslav
2015-01-01
On-shell methods offer an alternative definition of quantum field theory at tree-level, replacing Feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. In this paper we determine the simplest recursion relations needed to construct a general four-dimensional quantum field theory of massless particles. For this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of BCFW and Risager. The validity of each recursion relation hinges on the large momentum behavior of an n-point scattering amplitude under an m-line momentum shift, which we determine solely from dimensional analysis, Lorentz invariance, and locality. We show that all amplitudes in a renormalizable theory are 5-line constructible. Amplitudes are 3-line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. Remarkably, this implies the 3-line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. Moreover, all amplitudes in non-renormalizable theories without derivative interactions are constructible; with derivative interactions, a subset of amplitudes is constructible. We illustrate our results with examples from both renormalizable and non-renormalizable theories. Our study demonstrates both the power and limitations of recursion relations as a self-contained formulation of quantum field theory.
Physics Meets Art in the General Education Core
Dark, Marta L.; Hylton, Derrick J.
2018-01-01
This article describes a general education course offering, Physics and the Arts. During the development of this course, physics and arts faculty collaborated closely. We cover the usual physics phenomena for such a course--light, color, and sound--in addition to gravity, equilibrium, and spacetime. Goals of the course are to increase students'…
76 FR 1592 - National Poultry Improvement Plan; General Conference Committee Meeting
2011-01-11
...] National Poultry Improvement Plan; General Conference Committee Meeting AGENCY: Animal and Plant Health... General Conference Committee of the National Poultry Improvement Plan. DATES: The General Conference... Improvement Plan, VS, APHIS, 1498 Klondike Road, Suite 101, Conyers, GA 30094-5104; (770) 922-3496...
An Introduction to General Relativity and Cosmology
Energy Technology Data Exchange (ETDEWEB)
Wainwright, John [Department of Applied Mathematics, University/newline of Waterloo, Waterloo, Ontario, N2L 3G1 (Canada)
2007-04-07
The present volume is an introduction to general relativity and cosmology, at a level suitable for beginning graduate students or advanced undergraduates. The book consists of two main parts, the first entitled 'Elements of differential geometry', and the second 'The theory of gravitation'. Chapters 2-7, part I, introduce the basic ideas of differential geometry in a general setting, and are based on previously unpublished notes by one of the authors. On the one hand, the treatment is modern in that it uses a 'top-down' approach, i.e. starting with general differentiable manifolds, and deferring the introduction of a metric tensor until after the notions of affine connection and curvature have been introduced. On the other hand, the treatment is classical in that it relies heavily, though not exclusively, on index notation. The general material, chapters 1-7, is then followed by four more specialized chapters dealing with matters of specific interest for general relativity. Part II deals with general relativity and cosmology. The basic assumptions of the theory and its application to spherically symmetric gravitational fields are discussed in two chapters, and there is some historical material and motivation for the basic assumptions at the beginning of the book. The final chapter contains a detailed discussion of the Kerr solution. But the main emphasis in part II is on relativistic cosmology, in particular the analysis of cosmological models more general than the familiar Friedmann-Lemaitre (FL) models. The material on cosmology begins with a discussion of relativistic hydrodynamics and thermodynamics. The kinematical quantities (rate of expansion, shear, etc, of a timelike congruence) are introduced and their evolution equations are derived. There follows a description of the fluid model of the Universe and optical observations in such a model, within the framework of a general spacetime geometry. The discussion is subsequently
Premetric equivalent of general relativity: Teleparallelism
Itin, Yakov; Hehl, Friedrich W.; Obukhov, Yuri N.
2017-04-01
In general relativity (GR), the metric tensor of spacetime is essential since it represents the gravitational potential. In other gauge theories (such as electromagnetism), the so-called premetric approach succeeds in separating the purely topological field equation from the metric-dependent constitutive law. We show here that GR allows for a premetric formulation, too. For this purpose, we apply the teleparallel approach of gravity, which represents GR as a gauge theory based on the translation group. We formulate the metric-free topological field equation and a general linear constitutive law between the basic field variables. The requirement of local Lorentz invariance turns the model into a full equivalent of GR. Our approach opens a way for a natural extension of GR to diverse geometrical structures of spacetime.
On rotating charged dust in general relativity
International Nuclear Information System (INIS)
Islam, N.J.; Chittagong Univ.
1983-01-01
In this paper four main results are derived. Firstly, an exact and explicit non-cylindrically symmetric (but axially symmetric) solution is found for charged dust rotating with constant angular velocity in Newton-Maxwell theory for particles with equal mass and charge. Secondly, a general solution of the main equation is found describing differential rotation in Newton-Maxwell theory for particles of equal mass and charge. Thirdly, a new exact and explicit solution of the cylindrically symmetric Einstein-Maxwell interior equations is derived for charged dust rotating with constant angular velocity. An interesting property of the solution is that it is regular and well behaved for certain values of the parameters occurring in it. Fourthly, it is shown that for cylindrically symmetric, differentially rotating charged dust in general relativity there exists a solution in which the Lorentz force on a typical particle vanishes. (author)
Numerical Hydrodynamics and Magnetohydrodynamics in General Relativity
Directory of Open Access Journals (Sweden)
Font José A.
2008-09-01
Full Text Available This article presents a comprehensive overview of numerical hydrodynamics and magnetohydrodynamics (MHD in general relativity. Some significant additions have been incorporated with respect to the previous two versions of this review (2000, 2003, most notably the coverage of general-relativistic MHD, a field in which remarkable activity and progress has occurred in the last few years. Correspondingly, the discussion of astrophysical simulations in general-relativistic hydrodynamics is enlarged to account for recent relevant advances, while those dealing with general-relativistic MHD are amply covered in this review for the first time. The basic outline of this article is nevertheless similar to its earlier versions, save for the addition of MHD-related issues throughout. Hence, different formulations of both the hydrodynamics and MHD equations are presented, with special mention of conservative and hyperbolic formulations well adapted to advanced numerical methods. A large sample of numerical approaches for solving such hyperbolic systems of equations is discussed, paying particular attention to solution procedures based on schemes exploiting the characteristic structure of the equations through linearized Riemann solvers. As previously stated, a comprehensive summary of astrophysical simulations in strong gravitational fields is also presented. These are detailed in three basic sections, namely gravitational collapse, black-hole accretion, and neutron-star evolutions; despite the boundaries, these sections may (and in fact do overlap throughout the discussion. The material contained in these sections highlights the numerical challenges of various representative simulations. It also follows, to some extent, the chronological development of the field, concerning advances in the formulation of the gravitational field, hydrodynamics and MHD equations and the numerical methodology designed to solve them. To keep the length of this article reasonable
An Introduction to General Relativity and Cosmology
International Nuclear Information System (INIS)
Wainwright, John
2007-01-01
The present volume is an introduction to general relativity and cosmology, at a level suitable for beginning graduate students or advanced undergraduates. The book consists of two main parts, the first entitled 'Elements of differential geometry', and the second 'The theory of gravitation'. Chapters 2-7, part I, introduce the basic ideas of differential geometry in a general setting, and are based on previously unpublished notes by one of the authors. On the one hand, the treatment is modern in that it uses a 'top-down' approach, i.e. starting with general differentiable manifolds, and deferring the introduction of a metric tensor until after the notions of affine connection and curvature have been introduced. On the other hand, the treatment is classical in that it relies heavily, though not exclusively, on index notation. The general material, chapters 1-7, is then followed by four more specialized chapters dealing with matters of specific interest for general relativity. Part II deals with general relativity and cosmology. The basic assumptions of the theory and its application to spherically symmetric gravitational fields are discussed in two chapters, and there is some historical material and motivation for the basic assumptions at the beginning of the book. The final chapter contains a detailed discussion of the Kerr solution. But the main emphasis in part II is on relativistic cosmology, in particular the analysis of cosmological models more general than the familiar Friedmann-Lemaitre (FL) models. The material on cosmology begins with a discussion of relativistic hydrodynamics and thermodynamics. The kinematical quantities (rate of expansion, shear, etc, of a timelike congruence) are introduced and their evolution equations are derived. There follows a description of the fluid model of the Universe and optical observations in such a model, within the framework of a general spacetime geometry. The discussion is subsequently specialized to the Robertson
75 FR 28307 - National Council on Federal Labor-Management Relations Meeting
2010-05-20
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations is cancelling its June 2, 2010 meeting and rescheduling that meeting... of Federal employee organizations, Federal management organizations, and senior government officials...
Report to the Director General on the forty-fifth series of SAGSI meetings
International Nuclear Information System (INIS)
1997-11-01
Mr. Graham Andrew chaired the 45th Series of SAGSI Meetings. Seventeen members of SAGSI attended the meeting, which was held in Vienna from 10 to 14 November 1997. The Secretariat was represented by Mr. R. Hooper, Director of the Division of Concepts and Planning, and other senior staff. SAGSI addressed the items on the agenda approved by the Director General, considered its work programme for the next period, and recommended an agenda for the next SAGSI meeting. This report to the Director General was prepared using drafting groups and was approved in plenary
The mathematical theory of general relativity
Katkar, L N
2014-01-01
This book is prepared for M. Sc. Students of Mathematics and Physics. The aim of writing this book is to give the reader a feeling for the necessity and beauty of the laws of general relativity. The contents of the book will attract both mathematicians and physicists which provides motivation and applications of many ideas and powerful mathematical methods of modern analysis and differential geometry. An attempt has been made to make the presentation comprehensive, rigorous and yet simple. Most calculations and transformations have been carried out in great detail. KEY FEATURE: Numerous solved examples using the well known mathematical techniques viz., the tensors and the differential forms in each chapter.
New Area Law in General Relativity.
Bousso, Raphael; Engelhardt, Netta
2015-08-21
We report a new area law in general relativity. A future holographic screen is a hypersurface foliated by marginally trapped surfaces. We show that their area increases monotonically along the foliation. Future holographic screens can easily be found in collapsing stars and near a big crunch. Past holographic screens exist in any expanding universe and obey a similar theorem, yielding the first rigorous area law in big bang cosmology. Unlike event horizons, these objects can be identified at finite time and without reference to an asymptotic boundary. The Bousso bound is not used, but it naturally suggests a thermodynamic interpretation of our result.
Anholonomic Cauchy problem in general relativity
International Nuclear Information System (INIS)
Stachel, J.
1980-01-01
The Lie derivative approach to the Cauchy problem in general relativity is applied to the evolution along an arbitrary timelike vector field for the case where the dynamical degrees of freedom are chosen as the (generally anholonomic) metric of the hypersurface elements orthogonal to the vector field. Generalizations of the shear, rotation, and acceleration are given for a nonunit timelike vector field, and applied to the three-plus-one breakup of the Riemann tensor into components parallel and orthogonal to the vector field, resulting in the anholonomic Gauss--Codazzi equations. A similar breakup of the Einstein field equations results in the form of the constraint and evolution equations for the anholonomic case. The results are applied to the case of a space--time with a timelike Killing vector field (stationary field) to demonstrate their utility. Other possible applications, such as in the numerical integration of the field equations, are mentioned. Definitions are given of three-index shear, rotation, and acceleration tensors, and their use in a two-plus-two decomposition of the Riemann tensor and field equations is indicated
Introduction to general relativity and cosmology
Berger, Mitchell A
2018-01-01
The textbook aims to present general relativity and modern cosmology in a friendly form suitable for advanced undergraduates. The text begins with a self-contained introduction to the theory of manifolds and then develops the tools needed to understand curved spaces and curved spacetimes. Special relativity can then be understood in a geometrical context, bypassing some of the difficulties students have when encountering relativistic effects (e.g. time dilation and length contraction) for the first time. The theory of curvature and its effects leads to the Einstein field equations and its classic tests in the precession of Mercury and the deflection of starlight. The second part of the book covers modern cosmology, starting with the evolution equations for the expansion of the universe. The microwave background, evidence for dark matter, and the clustering of galaxies are examined in detail.
Optical drift effects in general relativity
Korzyński, Mikołaj; Kopiński, Jarosław
2018-03-01
We consider the question of determining the optical drift effects in general relativity, i.e. the rate of change of the apparent position, redshift, Jacobi matrix, angular distance and luminosity distance of a distant object as registered by an observer in an arbitrary spacetime. We present a fully relativistic and covariant approach, in which the problem is reduced to a hierarchy of ODE's solved along the line of sight. The 4-velocities and 4-accelerations of the observer and the emitter and the geometry of the spacetime along the line of sight constitute the input data. We build on the standard relativistic geometric optics formalism and extend it to include the time derivatives of the observables. In the process we obtain two general, non-perturbative relations: the first one between the gravitational lensing, represented by the Jacobi matrix, and the apparent position drift, also called the cosmic parallax, and the second one between the apparent position drift and the redshift drift. The applications of the results include the theoretical study of the drift effects of cosmological origin (so-called real-time cosmology) in numerical or exact Universe models.
Kinematics in special and general relativity
International Nuclear Information System (INIS)
Woodside, R.W.M.
1979-05-01
This thesis investigates the problem of motion for extended bodies from the viewpoint of classical field theory, where the classical field is the body's energy-momentum or matter tensor. In special relativity a symmetric and divergence-free matter tensor combined with inertial frames is used to generate a kinematics for extended bodies. In general relativity the author suggests an analogous kinematics and applies it to the simplest non-trivial example of static, spherical stars, looking for special sets of vector fields whose matter currents are conserved. Such a set of ten vector fields defines a special frame, and integrals of the conserved matter currents define ten momenta whcih give the kinematics. Application of de Rham cohomology theory shows that the conserved matter currents for isolated bodies will have mechanical potentials which enable the momenta to be found from flux integrals evaluated in the vacuum region surrounding the body. These potentials contain the full Riemann curvature, allowing a body's general relativistic momenta to be determined by its vacuum graviational field
General relativity. With applications to astrophysics
International Nuclear Information System (INIS)
Straumann, N.
2004-01-01
This text provides a comprehensive and timely introduction to general relativity. The foundations of the theory in Part I are thoroughly developed together with the required mathematical background from differential geometry in Part III. The six chapters in Part II are devoted to tests of general relativity and to many of its applications. Binary pulsars are studied in considerable detail. Much space is devoted to the study of compact objects, especially to black holes. This includes a detailed derivation of the Kerr solution, Israel's proof of his uniqueness theorem, and derivations of the basic laws of black hole physics. The final chapter of this part contains Witten's proof of the positive energy theorem. The book addresses undergraduate and graduate students in physics, astrophysics and mathematics. It is very well structured and should become a standard text for a modern treatment of gravitational physics. The clear presentation of differential geometry makes it also useful for strong theory and other fields of physics, classical as well as quantum. (orig.)
Kinematics of relative motion of test particles in general relativity
International Nuclear Information System (INIS)
Bazanski, S.L.
1977-01-01
A detailed mathematical study of the concept of geodesic deviation in pseudo-riemannian geometry is presented. A generalization of this concept to geodesic deviations of a higher order is then introduced and the second geodesic deviation is investigated in some detail. A geometric interpretation of the set of generalized geodesic deviations is given and applied in general relativity to determine a covariant and local description (with a desired order of accuracy) of test motions which take place in a certain finite neighbourhood of a given world line of an observer. The proper time evolution of two other objects related to geodesic deviation is also discussed: the space separation vector and the telescopic vector. This last name is given here to a field of null vectors along observer's world line which always point towards the same adjacent world line. The telescopic equations allow to determine the evolution of the frequency shift of electromagnetic radiation sent from and received on neighbouring world lines. On the basis of these equations also certain relations have been derived which connect the frequencies or frequency shifts with the curvature of space-time
An elementary course on general relativity
International Nuclear Information System (INIS)
Regge, T.
1983-01-01
This report gives an informal account of the theory of general relativity, for non-specialists. It does not contain any detailed technical expose of tensor calculus but relies instead on a number of intuitive arguments. After a brief historical introduction the notion of curvature is developed, first in two dimensions (as done originally by Gauss) and then in higher dimensions, following the ideas of Riemann. This curvature is then related to quantities of physical interest through the following steps: i) The equality of gravitational and inertial masses is discussed and presented as the ''weak equivalence principle''. ii) This is then extended to the ''strong equivalence principle'' according to the original programme of Einstein. iii) The ''strong equivalence principle'' implies the existence of a local inertial observer in any point of space-time. In a sufficiently small region of space-time this observer will not sense any gravitational field. iv) In a larger region the observer will, however, sense residual tidal forces. These forces are identified with the curvature of spacetime, to achieve a direct geometrical interpretation of gravity. v) Finally certain curvature components are related to the distribution of matter through Einstein's field equations. Section 4 contains a discussion of the classical tests of the theory and of the possibility of detecting gravitational waves. Sections 5 and 6 deal with cosmology and with the possible extension of the theory along the lines of the original ideas of Einstein, with emphasis on the dimensional reduction techniques of current interest. (orig.)
Dynamical laws of superenergy in general relativity
International Nuclear Information System (INIS)
Gomez-Lobo, Alfonso GarcIa-Parrado
2008-01-01
The Bel and Bel-Robinson tensors were introduced nearly 50 years ago in an attempt to generalize to gravitation the energy-momentum tensor of electromagnetism. This generalization was successful from the mathematical point of view because these tensors share mathematical properties which are remarkably similar to those of the energy-momentum tensor of electromagnetism. However, the physical role of these tensors in general relativity has remained obscure and no interpretation has achieved wide acceptance. In principle, they cannot represent energy and the term superenergy has been coined for the hypothetical physical magnitude lying behind them. In this work, we try to shed light on the true physical meaning of superenergy by following the same procedure which enables us to give an interpretation of the electromagnetic energy. This procedure consists in performing an orthogonal splitting of the Bel and Bel-Robinson tensors and analyzing the different parts resulting from the splitting. In the electromagnetic case such splitting gives rise to the electromagnetic energy density, the Poynting vector and the electromagnetic stress tensor, each of them having a precise physical interpretation which is deduced from the dynamical laws of electromagnetism (Poynting theorem). The full orthogonal splitting of the Bel and Bel-Robinson tensors is more complex but, as expected, similarities with electromagnetism are present. Also the covariant divergence of the Bel tensor is analogous to the covariant divergence of the electromagnetic energy-momentum tensor and the orthogonal splitting of the former is found. The ensuing equations are to the superenergy what the Poynting theorem is to electromagnetism. Some consequences of these dynamical laws of superenergy are explored, among them the possibility of defining superenergy radiative states for the gravitational field
76 FR 19104 - National Institute of General Medical Sciences; Notice of Closed Meeting
2011-04-06
... General Medical Sciences; Notice of Closed Meeting Pursuant to section 10(d) of the Federal Advisory... clearly unwarranted invasion of personal privacy. Name of Committee: National Institute of General Medical Sciences Special Emphasis Panel; 2011 NIH Director's Pioneer Awards. Date: May 2-4, 2011. Time: 7:45 a.m...
Victories and defeats in general relativity theory
International Nuclear Information System (INIS)
Moeller, C.
1977-01-01
Only within the last 20 years has it been possible to conduct far-reaching experimental tests of the validity of Einstein's General Relativity Theory. Experimental confirmation in some fields is embarrassed by considerable difficulties in applying the theory to cosmic systems, which indicate that such major systems lie at the limit of the theory's applicability. The lecture here reproduced discusses both the successes and the limitations of the theory, starting with its replacement of the absolute space-time theory of Newton and its historical replacement by the relativistic gravitational postulates of Einstein which, in spite of its more complicated postulates, nevertheless introduced a great simplicity and comprehensiveness into the overall conception of nature. This theoretical 'beauty', however, can only be trusted if vindicated experimentally, which has to a considerable extent proved to be the case. For weak fields Newtonian and Einsteinian concepts coincide, while for stronger fields, and velocities not far from that of light, Einstein's theory is superior, giving,for example, an excellent correspondence with the precession of the perehelion of Mercury. On a larger scale, however, the theory appears to lead to conclusions which would invalidate the very concepts of space and time, even within a finite time-interval. A more generalized theory seems to be required. (A.D.N.)
Spherical shock waves in general relativity
International Nuclear Information System (INIS)
Nutku, Y.
1991-01-01
We present the metric appropriate to a spherical shock wave in the framework of general relativity. This is a Petrov type-N vacuum solution of the Einstein field equations where the metric is continuous across the shock and the Riemann tensor suffers a step-function discontinuity. Spherical gravitational waves are described by type-N Robinson-Trautman metrics. However, for shock waves the Robinson-Trautman solutions are unacceptable because the metric becomes discontinuous in the Robinson-Trautman coordinate system. Other coordinate systems that have so far been introduced for describing Robinson-Trautman solutions also suffer from the same defect. We shall present the C 0 -form of the metric appropriate to spherical shock waves using Penrose's approach of identification with warp. Further extensions of Penrose's method yield accelerating, as well as coupled electromagnetic-gravitational shock-wave solutions
Rapidly rotating polytropes in general relativity
Cook, Gregory B.; Shapiro, Stuart L.; Teukolsky, Saul A.
1994-01-01
We construct an extensive set of equilibrium sequences of rotating polytropes in general relativity. We determine a number of important physical parameters of such stars, including maximum mass and maximum spin rate. The stability of the configurations against quasi-radial perturbations is diagnosed. Two classes of evolutionary sequences of fixed rest mass and entropy are explored: normal sequences which behave very much like Newtonian evolutionary sequences, and supramassive sequences which exist solely because of relativistic effects. Dissipation leading to loss of angular momentum causes a star to evolve in a quasi-stationary fashion along an evolutionary sequence. Supramassive sequences evolve towards eventual catastrophic collapse to a black hole. Prior to collapse, the star must spin up as it loses angular momentum, an effect which may provide an observational precursor to gravitational collapse to a black hole.
On thick domain walls in general relativity
Goetz, Guenter; Noetzold, Dirk
1989-01-01
Planar scalar field configurations in general relativity differ considerably from those in flat space. It is shown that static domain walls of finite thickness in curved space-time do not possess a reflection symmetry. At infinity, the space-time tends to the Taub vacuum on one side of the wall and to the Minkowski vacuum (Rindler space-time) on the other. Massive test particles are always accelerated towards the Minkowski side, i.e., domain walls are attractive on the Taub side, but repulsive on the Minkowski side (Taub-vacuum cleaner). It is also proved that the pressure in all directions is always negative. Finally, a brief comment is made concerning the possibility of infinite, i.e., bigger than horizon size, domain walls in our universe. All of the results are independent of the form of the potential V(phi) greater than or equal to 0 of the scalar field phi.
Proceedings of a meeting on radiation shielding and related topics
International Nuclear Information System (INIS)
1978-01-01
This is a proceedings of a meeting on radiation shielding and related topics held on Feb. 22 and 23 in 1978 at Nuclear Engineering Research Laboratory of University of Tokyo. The reports includes the following items (1) studies on neutronics with accelerators (2) radiation damage (3) shielding design (4) radiation streaming (5) shielding experiments from a point of view of radiation measurements (6) shielding benchmark experiments (7) prospects on the study of neutronics. All items are written in Japanese. (auth.)
Singular Null Hypersurfaces in General Relativity
International Nuclear Information System (INIS)
Dray, T
2006-01-01
Null hypersurfaces are a mathematical consequence of the Lorentzian signature of general relativity; singularities in mathematical models usually indicate where the interesting physics takes place. This book discusses what happens when you combine these ideas. Right from the preface, this is a no-nonsense book. There are two principal approaches to singular shells, one distributional and the other 'cut and paste'; both are treated in detail. A working knowledge of GR is assumed, including familiarity with null tetrads, differential forms, and 3 + 1 decompositions. Despite my own reasonably extensive, closely related knowledge, there was material unfamiliar to me already in chapter 3, although I was reunited with some old friends in later chapters. The exposition is crisp, with a minimum of transition from chapter to chapter. In fact, my main criticism is that there is no clear statement of the organization of the book, nor is there an index. Everything is here, and the story is compelling if you know what to look for, although it is less easy to follow the story if you are not already familiar with it. But this is really a book for experts, and the authors certainly qualify, having played a significant role in developing and extending the results they describe. It is also entirely appropriate that the book is dedicated to Werner Israel, who pioneered the thin-shell approach to (non-null) singular surfaces and later championed the use of similar methods for analysing null shells. After an introductory chapter on impulsive signals, the authors show how the Bianchi identities can be used to classify spacetimes with singular null hypersurfaces. This approach, due to the authors, generalizes the framework originally proposed by Penrose. While astrophysical applications are discussed only briefly, the authors point out that detailed physical characteristics of signals from isolated sources can be determined in this manner. In particular, they describe the behaviour of
BOOK REVIEW: Modern Canonical Quantum General Relativity
Kiefer, Claus
2008-06-01
The open problem of constructing a consistent and experimentally tested quantum theory of the gravitational field has its place at the heart of fundamental physics. The main approaches can be roughly divided into two classes: either one seeks a unified quantum framework of all interactions or one starts with a direct quantization of general relativity. In the first class, string theory (M-theory) is the only known example. In the second class, one can make an additional methodological distinction: while covariant approaches such as path-integral quantization use the four-dimensional metric as an essential ingredient of their formalism, canonical approaches start with a foliation of spacetime into spacelike hypersurfaces in order to arrive at a Hamiltonian formulation. The present book is devoted to one of the canonical approaches—loop quantum gravity. It is named modern canonical quantum general relativity by the author because it uses connections and holonomies as central variables, which are analogous to the variables used in Yang Mills theories. In fact, the canonically conjugate variables are a holonomy of a connection and the flux of a non-Abelian electric field. This has to be contrasted with the older geometrodynamical approach in which the metric of three-dimensional space and the second fundamental form are the fundamental entities, an approach which is still actively being pursued. It is the author's ambition to present loop quantum gravity in a way in which every step is formulated in a mathematically rigorous form. In his own words: 'loop quantum gravity is an attempt to construct a mathematically rigorous, background-independent, non-perturbative quantum field theory of Lorentzian general relativity and all known matter in four spacetime dimensions, not more and not less'. The formal Leitmotiv of loop quantum gravity is background independence. Non-gravitational theories are usually quantized on a given non-dynamical background. In contrast, due to
On the ultrarelativistic limit of general relativity
International Nuclear Information System (INIS)
Dautcourt, G.
1998-01-01
As is well-known, Newton's gravitational theory can be formulated as a four-dimensional space-time theory and follows as singular limit from Einstein's theory, if the velocity of light tends to the infinity. Here 'singular' stands for the fact, that the limiting geometrical structure differs from a regular Riemannian space-time. Geometrically, the transition Einstein → Newton can be viewed as an 'opening' of the light cones. This picture suggests that there might be other singular limits of Einstein's theory: Let all light cones shrink and ultimately become part of a congruence of singular world lines. The limiting structure may be considered as a null hypersurface embedded in a five-dimensional spacetime. While the velocity of light tends to zero here, all other velocities tend to the velocity of light. Thus one may speak of an ultrarelativistic limit of General Relativity. The resulting theory is as simple as Newton's gravitational theory, with the basic difference, that Newton's elliptic differential equation is replaced by essentially ordinary differential equations, with derivatives tangent to the generators of the singular congruence. The Galilei group is replaced by the Carroll group introduced by Levy-Leblond. We suggest to study near ultrarelativistic situations with a perturbational approach starting from the singular structure, similar to post-Newtonian expansions in the c → ∞ case. (author)
Inflation and bubbles in general relativity
Laguna-Castillo, Pablo; Matzner, Richard A.
1986-11-01
Following Israel's study of singular hypersurfaces and thin shells in general relativity, the complete set of Einstein's field equations in the presence of a bubble boundary SIGMA is reviewed for all spherically symmetric embedding four-geometries M+/-. The mapping that identifies points between the boundaries Σ+ and Σ- is obtained explicitly when the regions M+ and M- are described by a de Sitter and a Minkowski metric, respectively. In addition, the evolution of a bubble with vanishing surface energy density is studied in a spatially flat Robertson-Walker space-time, for region M- radiation dominated with a vanishing cosmological constant, and an energy equation in M+ determined by the matching. It is found that this type of bubble leads to a ``worm-hole'' matching; that is, an infinite extent exterior of a sphere is joined across the wall to another infinite extent exterior of a sphere. Interior-interior matches are also possible. Under this model, solutions for a bubble following a Hubble law are analyzed. Numerical solutions for bubbles with constant tension are also obtained.
Direction dependent structures in general relativity
International Nuclear Information System (INIS)
Herberthson, M.
1993-01-01
This thesis deals with, within the theory of general relativity, asymptotic properties of certain types of space-times. Using conformal transformations, it is possible to describe asymptotic properties of a physical space-time in terms of the local behaviour of the new, rescaled space-time. One then uses so called direction dependent structures. We present two such structures and applications to them. One structure is used in the study of spacelike (or spatial) infinity. We discuss the asymptotic conditions on the gravitational and the electromagnetic field, especially the conditions put on directions corresponding to future and past null infinity. It is shown that these fields have desired physical properties. The other structure is used in connection with timelike infinity. Using this structure, we suggest a new definition of timelike infinity. This definition differs significantly from earlier definitions, and leads to the concept of asymptotically stationary space-times. We also suggest a definition of asymptotic flatness at future null infinity, and a definition of a black hole which is, in a sense, local. Both of these definitions fit nicely into the structure. (24 refs.)
General Quantum Meet-in-the-Middle Search Algorithm Based on Target Solution of Fixed Weight
Fu, Xiang-Qun; Bao, Wan-Su; Wang, Xiang; Shi, Jian-Hong
2016-10-01
Similar to the classical meet-in-the-middle algorithm, the storage and computation complexity are the key factors that decide the efficiency of the quantum meet-in-the-middle algorithm. Aiming at the target vector of fixed weight, based on the quantum meet-in-the-middle algorithm, the algorithm for searching all n-product vectors with the same weight is presented, whose complexity is better than the exhaustive search algorithm. And the algorithm can reduce the storage complexity of the quantum meet-in-the-middle search algorithm. Then based on the algorithm and the knapsack vector of the Chor-Rivest public-key crypto of fixed weight d, we present a general quantum meet-in-the-middle search algorithm based on the target solution of fixed weight, whose computational complexity is \\sumj = 0d {(O(\\sqrt {Cn - k + 1d - j }) + O(C_kj log C_k^j))} with Σd i =0 Ck i memory cost. And the optimal value of k is given. Compared to the quantum meet-in-the-middle search algorithm for knapsack problem and the quantum algorithm for searching a target solution of fixed weight, the computational complexity of the algorithm is lower. And its storage complexity is smaller than the quantum meet-in-the-middle-algorithm. Supported by the National Basic Research Program of China under Grant No. 2013CB338002 and the National Natural Science Foundation of China under Grant No. 61502526
General relativity invariance and string field theory
International Nuclear Information System (INIS)
Aref'eva, I.Ya.; Volovich, I.V.
1987-04-01
The general covariance principle in the string field theory is considered. The algebraic properties of the string Lie derivative are discussed. The string vielbein and spin connection are introduced and an action invariant under general co-ordinate transformation is proposed. (author). 18 refs
Gravitational Wave in Linear General Relativity
Cubillos, D. J.
2017-07-01
General relativity is the best theory currently available to describe the interaction due to gravity. Within Albert Einstein's field equations this interaction is described by means of the spatiotemporal curvature generated by the matter-energy content in the universe. Weyl worked on the existence of perturbations of the curvature of space-time that propagate at the speed of light, which are known as Gravitational Waves, obtained to a first approximation through the linearization of the field equations of Einstein. Weyl's solution consists of taking the field equations in a vacuum and disturbing the metric, using the Minkowski metric slightly perturbed by a factor ɛ greater than zero but much smaller than one. If the feedback effect of the field is neglected, it can be considered as a weak field solution. After introducing the disturbed metric and ignoring ɛ terms of order greater than one, we can find the linearized field equations in terms of the perturbation, which can then be expressed in terms of the Dalambertian operator of the perturbation equalized to zero. This is analogous to the linear wave equation in classical mechanics, which can be interpreted by saying that gravitational effects propagate as waves at the speed of light. In addition to this, by studying the motion of a particle affected by this perturbation through the geodesic equation can show the transversal character of the gravitational wave and its two possible states of polarization. It can be shown that the energy carried by the wave is of the order of 1/c5 where c is the speed of light, which explains that its effects on matter are very small and very difficult to detect.
The Concept of General Relativity is not Related to Reality
Kotas, Ronald
2015-04-01
The concept of general relativity is not related to reality. It is not real or factual Science. GR cannot account for objects falling to earth or for the weight of objects sitting on the earth. The Cavendish demonstration showing the attraction between two masses at right angles to earth's gravity, is not explained by GR. No one can prove the existence of ``space fabric.'' The concept of ``space time'' effects causing gravitational attraction between masses is wrong. Conservation law of energy - momentum does not exist in GR. LIGO fails in detecting ``gravity waves'' because there is no ``space fabric'' to transmit them. The Gravity B Probe data manipulated to show some effects, is not proof of ``space fabric.'' It is Nuclear Quantum Gravitation that provides clear definitive explanation of Gravity and Gravitation. It is harmonious with Newtonian and Quantum Mechanics, and Scientific Logic. Nuclear Quantum Gravitation has 10 clear, Scientific proofs and 21 more good indications. With this theory the Physical Forces are Unified. See: OBSCURANTISM ON EINSTEIN GRAVITATION? http://www.santilli-foundation.org/inconsistencies-gravitation.php and Einstein's Theory of Relativity versus Classical Mechanics, by Paul Marmet http://www.newtonphysics.on.ca/einstein/
Operating experience relating to on-site electric power sources. Proceedings of a Specialist Meeting
International Nuclear Information System (INIS)
1986-02-01
The reliability of on-site electric power sources of nuclear power plants usually consisting of diesel generators, gas turbine generators and DC power sources, has been a matter of concern during reactor operations. The frequent recurrence and the important consequences of failures relating to on-site electric power sources have led to a general consensus that they form one of the most significant features influencing the total performance of the safety Systems. This has also been confirmed by surveys performed on the incidents reported through the NEA Incident Reporting System (IRS). Accordingly, a recommendation to organise a Specialist Meeting on the subject was made at the third annual meeting of CSNI Principal Working Group No. 1 (Operating Experience and Human Factors). At the 12. meeting of the CSNI held in November 1984. the Committee endorsed the proposal and accepted an offer by the United Kingdom to host and organise the Specialist Meeting. The Specialist Meeting, sponsored by the CSNI, was held in London, United Kingdom from 16 to 18 October 1985. It was hosted by H.M. Nuclear Installations Inspectorate of the Health and Safety Executive. The purpose of the meeting was to promote the exchange of Information on operating experience relating to on-site electric power sources and to look for measures to further improve their reliability In the areas of design, operation and licensing. The meeting was organised by a Programme Group which included nominated members of CSNI PWG No. 1. the Programme Group met in May and June 1985 in Paris to agree on the programme and practical arrangements for the meeting. As a result of the review of the abstracts which had been contributed in response to the Call for Papers, 28 papers were accepted for presentation during the meeting. Approximately 60 delegates from 13 Member countries, and the NEA Secretariat, attended the meeting. Session summaries prepared by the respective session chairmen are Included prior to the
2012-01-24
...] General Conference Committee of the National Poultry Improvement Plan; Cancellation of Meeting AGENCY... Improvement Plan scheduled for January 25, 2012, has been canceled. FOR FURTHER INFORMATION CONTACT: Dr. C. Stephen Roney, Senior Coordinator, National Poultry Improvement Plan, VS, APHIS, 1506 Klondike Road, Suite...
30 CFR 285.525 - What general requirements must a financial assurance instrument meet?
2010-07-01
... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What general requirements must a financial assurance instrument meet? 285.525 Section 285.525 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT... CONTINENTAL SHELF Payments and Financial Assurance Requirements Requirements for Financial Assurance...
29 CFR 4.172 - Meeting requirements for particular fringe benefits-in general.
2010-07-01
... 29 Labor 1 2010-07-01 2010-07-01 true Meeting requirements for particular fringe benefits-in... particular fringe benefits—in general. Where a fringe benefit determination specifies the amount of the..., as such costs are properly a business expense of the employer. If prevailing fringe benefits for...
A Live-Time Relation: Motion Graphics meets Classical Music
DEFF Research Database (Denmark)
Steijn, Arthur
2014-01-01
In our digital age, we frequently meet fine examples of live performances of classical music with accompanying visuals. Yet, we find very little theoretical or analytical work on the relation between classical music and digital temporal visuals, nor on the process of creating them. In this paper, I...... to be experienced interconnected and simultaneously with live music. These cases have been created in connection with an on-going EU funded inter-regional project (Interreg), which e.g. aims to show examples of ways in which digital technologies can be integrated in live performances of classical music...... and practice derived from the extensive domain of visual music. The other stems from perception theories related to concepts of liveness. Finally I look into how theories and terminology from these fields might contribute to the evolving design model....
Black hole dynamics in general relativity
Indian Academy of Sciences (India)
the documentary on his life made by IUCAA and Vignan Prasar. Through ... There is a large body of physicists he molded both through his physics lectures and by the way he lived. It is easy to understand the unusually deep reverence they ... At each point of S there are exactly two future pointing null normals to it, generally.
Relative effectiveness of generalized Mantel-Haenszel ...
African Journals Online (AJOL)
The study compared the power of Differential Item Functioning (DIF) detection for ordinal test items among Generalized Mantel Haenszel (GMH), Simultaneous Item Bias Test (SIBTEST), and Logistic Discriminant Function Analysis (LDFA) methods. It also determined the relationship between the proportions of test items that ...
75 FR 81678 - National Council on Federal Labor-Management Relations Meeting
2010-12-28
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following dates-- Wednesday, January 19, 2011... representatives of Federal employee organizations, Federal management organizations, and senior government...
78 FR 77172 - National Council on Federal Labor-Management Relations Meeting
2013-12-20
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77 FR 11600 - National Council on Federal Labor-Management Relations Meeting
2012-02-27
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following dates-- Wednesday, April 18, 2012... representatives of Federal employee organizations, Federal management organizations, and senior government...
75 FR 47033 - National Council on Federal Labor-Management Relations Meeting
2010-08-04
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations is canceling its September 1, 2010 meeting and rescheduling that... of representatives of Federal employee organizations, Federal management organizations, and senior...
77 FR 74228 - National Council on Federal Labor-Management Relations Meeting
2012-12-13
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following dates-- Wednesday, January 16, 2013... representatives of Federal employee organizations, Federal management organizations, and senior government...
International VLBI Service for Geodesy and Astrometry 2004 General Meeting Proceedings
Vandenberg, Nancy R. (Editor); Baver, Karen D. (Editor)
2004-01-01
This volume is the proceedings of the third General Meeting of the International VLBI Service for Geodesy and Astromctry IVS), held in Otlawa, Canada, February 9-11,2004. The keynote of the third GM was visions for the next decade following the main theme of "Today's Results and Tomorrow's Vision". with a recognition that the outstanding VLBI results available today are the foundation and motivation for the next generation VLBI system requirements. The goal of the meeting was to provide an interesting and informative program for a wide cross section of IVS members, including station operators, program managers, and analysts.
Testing general relativity using a bouncing ball
Directory of Open Access Journals (Sweden)
Shiuan-Ni Liang
2014-01-01
Full Text Available In a recent article (Liang and Lan, (2011, we showed that the trajectories predicted by general-relativistic and Newtonian mechanics from the same parameters and initial conditions for a low-speed weak-gravity bouncing ball system will rapidly disagree completely if the trajectories are chaotic. Here, we determine how accurate the parameters and initial conditions of the system must be known so that the two different calculated chaotic trajectories are sufficiently accurate for an empirical test.
On ``minimally curved spacetimes'' in general relativity
Dadhich, Naresh
1997-01-01
We consider a spacetime corresponding to uniform relativistic potential analogus to Newtonian potential as an example of ``minimally curved spacetime''. We also consider a radially symmetric analogue of the Rindler spacetime of uniform proper acceleration relative to infinity.
Recent Developments in Gravitation - Proceedings of the Relativity Meeting - 89
Verdaguer, E.; Garriga, J.; Céspedes, J.
1990-10-01
The Table of Contents for the full book PDF is as follows: * Foreword * I. INVITED LECTURES * Low Energy Effects of Quantum Gravity * Rigid Motion lnvariance of Newtonian and Einatein's Theories of General Relativity * General Relativity and the Early Universe * Computer Algebra and Exact Solutions of the Einstein Equations * Gravitational Waves * II. REVIEW TALKS * Classical Relativistic Particles with Spin * Testing Flux Conservative Methods in Numerical Relativity * Symmetries in General Relativity and the Problem of Symmetry Inheritance * Clifford Algebra Approach to Gravitation: Applications to Symmetries and to Twisting, Type-N Fields * Unusual Frames of the Space-Time * Massive Photon Modes in Q.E.D. and Abnormal e+ e- Pair Production * Repulsive Gravity: A Current State of Understanding * Physics versus Metaphysics in Collision between Plane Gravitational Waves * Primordial Black Holes and FRW Cosmology * What Does Morphological Segregation of Galaxies Tell Us about Galaxy Formation? * III. SHORT COMMUNICATIONS * A Demianski Cavity with Small Rotation Parameter in a Dust Universe with Cosmological Constant * Relation between Quasirigidity and Weak Rigidity in Weak Fields * Almost-Product Structures in Relativity * On the Solutions of Quantum Field Equations in Curved Space-Time * Perturbative Methods for Type D Space-Time * The Energy-Momentum Tensor of Two Perfect Fluids * Two Fluids Solutions of Einstein Equations * Gravitational Wave Detection: The Problem of Estimating a Signal's Arrival Time * Quantum Particles Produced during Cosmic String Formation * Electric Neutrality and the Jordan-Thiry Scalar Field * Why Do Spinors Appear in Relativity? * Variational Principles and Quantum Gravity * A Nelson Like Approach to Quantum Mechanics on a Maximally Symmetric Manifold * A Note on the Scalar Product in Relativistic Quantum Mechanics * On the Tolman Bondi Solution of Einstein's Equations. Numerical Applications * The Dirac Equation in Two Rectilinear
78 FR 40202 - National Council on Federal Labor-Management Relations Meeting
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76 FR 9615 - National Council on Federal Labor-Management Relations Meetings
2011-02-18
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meetings... Federal Labor-Management Relations plans to meet on the following dates-- Wednesday, March 16, 2011... meeting dates. The Council is an advisory body composed of representatives of Federal employee...
Large-scale tides in general relativity
Energy Technology Data Exchange (ETDEWEB)
Ip, Hiu Yan; Schmidt, Fabian, E-mail: iphys@mpa-garching.mpg.de, E-mail: fabians@mpa-garching.mpg.de [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, 85741 Garching (Germany)
2017-02-01
Density perturbations in cosmology, i.e. spherically symmetric adiabatic perturbations of a Friedmann-Lemaȋtre-Robertson-Walker (FLRW) spacetime, are locally exactly equivalent to a different FLRW solution, as long as their wavelength is much larger than the sound horizon of all fluid components. This fact is known as the 'separate universe' paradigm. However, no such relation is known for anisotropic adiabatic perturbations, which correspond to an FLRW spacetime with large-scale tidal fields. Here, we provide a closed, fully relativistic set of evolutionary equations for the nonlinear evolution of such modes, based on the conformal Fermi (CFC) frame. We show explicitly that the tidal effects are encoded by the Weyl tensor, and are hence entirely different from an anisotropic Bianchi I spacetime, where the anisotropy is sourced by the Ricci tensor. In order to close the system, certain higher derivative terms have to be dropped. We show that this approximation is equivalent to the local tidal approximation of Hui and Bertschinger [1]. We also show that this very simple set of equations matches the exact evolution of the density field at second order, but fails at third and higher order. This provides a useful, easy-to-use framework for computing the fully relativistic growth of structure at second order.
BOOK REVIEW: Advanced Mechanics and General Relativity Advanced Mechanics and General Relativity
Louko, Jorma
2011-04-01
Joel Franklin's textbook `Advanced Mechanics and General Relativity' comprises two partially overlapping, partially complementary introductory paths into general relativity at advanced undergraduate level. Path I starts with the Lagrangian and Hamiltonian formulations of Newtonian point particle motion, emphasising the action principle and the connection between symmetries and conservation laws. The concepts are then adapted to point particle motion in Minkowski space, introducing Lorentz transformations as symmetries of the action. There follows a focused development of tensor calculus, parallel transport and curvature, using examples from Newtonian mechanics and special relativity, culminating in the field equations of general relativity. The Schwarzschild solution is analysed, including a detailed discussion of the tidal forces on a radially infalling observer. Basics of gravitational radiation are examined, highlighting the similarities to and differences from electromagnetic radiation. The final topics in Path I are equatorial geodesics in Kerr and the motion of a relativistic string in Minkowski space. Path II starts by introducing scalar field theory on Minkowski space as a limit of point masses connected by springs, emphasising the action principle, conservation laws and the energy-momentum tensor. The action principle for electromagnetism is introduced, and the coupling of electromagnetism to a complex scalar field is developed in a detailed and pedagogical fashion. A free symmetric second-rank tensor field on Minkowski space is introduced, and the action principle of general relativity is recovered from coupling the second-rank tensor to its own energy-momentum tensor. Path II then merges with Path I and, supplanted with judicious early selections from Path I, can proceed to the Schwarzschild solution. The choice of material in each path is logical and focused. A notable example in Path I is that Lorentz transformations in Minkowki space are introduced
Scientific Overview: CSCI-CITAC Annual General Meeting and Young Investigators' Forum 2015.
Zhao, Eric Y; Zhou, Tianwei Ellen; Benesch, Matthew G K; Dey, Ayan; Liu, Peter; Steadman, Patrick E; Zaslavsky, Kirill; Schneider, Raphael; Kuzyk, Alexandra
2016-10-14
The 2015 Annual General Meeting of The Canadian Society of Clinician Investigators (CSCI) and Clinician Investigator Trainee Association of Canada/Association des Cliniciens-Chercheurs en Formation du Canada (CITAC/ACCFC) was held in Toronto November 23-25, 2015, in conjunction with The University of Toronto Clinician Investigator Program Research Day. The theme for this year's meeting was "It takes a village" and the focus was the various support systems necessary to train a successful clinician scientist. The meeting featured an opening presentation by Dr. Vincent Dumez and workshops by Dr. Peter Nickerson, Dr. Jane Aubin, Dr. Kelly Warmington and Dr. Norman Rosenblum, and MD/PhD trainees Nardin Samuel, Kevin Wang and Kirill Zaslavsky. The keynote speakers were Dr. David Malkin (Hospital for Sick Children) who received the CSCI-RCPSC Henry Friesen Award, Dr. Brent Richards (McGill University) who received the Joe Doupe Award and Ernesto Shiffrin (Lady Davis Institute) who received the Distinguished Scientist Award. As always, the conference showcased outstanding scientific presentations from clinician investigator trainees from across the country at the Young Investigators' Forum. The research topics, which ranged from basic sciences to clinical medicine and translational work, are summarized in this review. Over 90 abstracts were presented at this year's meeting during two poster sessions, with several of the outstanding abstracts selected for oral presentations.
Indian Academy of Sciences (India)
At the invitation of the Physical Research. Laboratory, the 58th Annual Meeting of the. Academy was held at Ahmedabad from 6 to 9. November 1992. The meetings were held at the. Physical Research Laboratory (PRL) and the. Space Applications Centre (SAC) and were organized by PRl, in cooperation with ~AC, the.
Regionalisation of general practice training--are we meeting the needs of rural Australia?
Campbell, David G; Greacen, Jane H; Giddings, Patrick H; Skinner, Lesley P
2011-06-06
The concept of "social accountability" has underpinned the development of many medical education programs over the past decade. Success of the regionalisation of the general practice training program in Australia will ultimately be measured by the ability of the program to deliver a sufficient rural general practice workforce to meet the health needs of rural communities. Regionalisation of general practice training in Australia arose from the 1998 recommendations of the Ministerial Review of General Practice Training. The resultant competitive structure adopted by government was not the preferred option of the Review Committee, and may be a negative influence on rural workforce, as the competitive corporate structure of regional training providers has created barriers to meaningful vertical integration. Available data suggest that the regionalised training program is not yet providing a sustainable general practice workforce to rural Australia. The current increase in medical student and general practice training places provides an opportunity to address some of these issues. In particular, it is recommended that changes be made to registrar selection processes, the rural pipeline and vertical integration of training, and training for procedural rural practice. To achieve these goals, perhaps it is time for another comprehensive ministerial review of general practice training in Australia.
The Two-Dimensional Analogue of General Relativity
Lemos, José P. S.; Sá, Paulo M.
1993-01-01
General Relativity in three or more dimensions can be obtained by taking the limit $\\omega\\rightarrow\\infty$ in the Brans-Dicke theory. In two dimensions General Relativity is an unacceptable theory. We show that the two-dimensional closest analogue of General Relativity is a theory that also arises in the limit $\\omega\\rightarrow\\infty$ of the two-dimensional Brans-Dicke theory.
Relative orientation of coordinate systems in general relativity
Barreda, M.; Olivert, J.
2004-05-01
We study under which conditions a space-time admits at each point coordinate systems with the same orientation. A generalization of the Fermi derivative to a linear connection compatible with the metric is considered: Fermi connection. Using techniques of Lie groups, it is proved that the parallel transport associated to the Fermi connection corresponds to spatial rotations. Hence, those space-times for which a Fermi connection with vanishing curvature can be defined admit at each point coordinate systems with the same orientation. Conformally flat solutions with a perfect fluid and the equation of state ρ = - 3p are considered. These solutions, when Θ{2} = 24πρ, admit at each point coordinate systems with the same orientation. An example is the Robertson-Walker universe of infinite radius.
DSR Theories, Conformal Group and Generalized Commutation Relation
International Nuclear Information System (INIS)
Leiva, Carlos
2006-01-01
In this paper the relationship of DSR theories and Conformal Group is reviewed. On the other hand, the relation between DSR Magueijo Smolin generators and generalized commutation relations is also shown
Generalized uncertainty relations and characteristic invariants for the multimode states
International Nuclear Information System (INIS)
Sudarshan, E.C.G.; Chiu, C.B.; Bhamathi, G.
1995-01-01
The close relationship between the zero-point energy, the uncertainty relation, coherent states, squeezed states, and correlated states for one mode is investigated. This group theoretic perspective of the problem enables the parametrization and identification of their multimode generalization. A simple and efficient method of determining the canonical structure of the generalized correlated states is presented. Implication of canonical commutation relations for correlations are not exhausted by the Heisenberg uncertainty relation, not even by the Schroedinger-Robertson uncertainty inequality, but there are relations in the multimode case that are the generalization of the Schroedinger-Robertson relation
BOOK REVIEW: Equations of Motion in General Relativity Equations of Motion in General Relativity
Schäfer, Gerhard
2012-03-01
Devoted exclusively to the problem of motion in general relativity, this book by H. Asada, T. Futamase, and P. A. Hogan is highly welcome to close up a gap in the book sector presenting a concise account of theoretical developments and results on gravitational equations of motion achieved since the discovery of the binary neutron star system PSR 1913+16 in 1974. For the most part, the book is concerned with the development and application of the important post-Newtonian approximation (PNA) framework which allows for highly efficient approximate analytic solutions of the Einstein field equations for many-body systems in terms of a slow-motion and weak-field ordering parameter. That approximation scheme is shown to be applicable also to the external motion of strongly self-gravitating objects if their internal dynamics is frozen in (strong field point particle limit) and the external conditions fit. Relying on the expertise of the authors, the PNA framework is presented in a form which, at the 1PNA level, had become famous through the work by Einstein, Infeld and Hoffmann in 1938; therein, surface integrals over gravitational field expressions in the outside-body regime play a crucial role. Other approaches which also succeeded with the highest achieved PNA level so far are mentioned too, if not fully exhaustively with respect to the highest, the 3.5PNA level which contains the inverse power of the speed of light to the seventh order. Regarding the 3PNA, the reader gains a clear understanding of how the equations of motion for binary systems with compact components come about. Remarkably, no deviation from four-dimensional space-time is needed. Various explicit analytic expressions are derived for binary systems: the periastron advance and the orbital period at the 2PNA, the orbital decay through gravitational radiation reaction at the 2.5PNA, and effects of the gravitational spin-orbit and spin-spin couplings on the orbital motion. Also the propagation of light
General Relativity and the Accelerated Expansion of the Universe
Indian Academy of Sciences (India)
General Relativity and the Accelerated. Expansion of the Universe. Patrick Das Gupta. Keywords. General relativity, accelerating universe, vacuum energy, cos- mology, Nobel Prize 2011. Patrick Das Gupta is a professor in the Depart- ment of Physics and. Astrophysics, University of. Delhi. His research interests lie in ...
The formalism of the general theory of relativity as a theory of interaction
International Nuclear Information System (INIS)
Gottlieb, I.
1980-01-01
It is postulated that the formalism of the general theory of relativity can be used as a theory of interaction starting from Hamilton's principle with Lagrange's function. In the case of the pure gravitational field we meet again a theory of gravitation which gives all the basic tests of the general theory of relativity. In the case of the pure electromagnetic field, the basic equations are given. The motion of a ''free'' electron in the space curved by the electrostatic field of the nucleus is given as an application, employing Dirac's equation and Tetrode-Fock formalism. (author)
Proceedings of the 7th Italian conference on general relativity and gravitational physics
International Nuclear Information System (INIS)
Bruzzo, U.; Cianci, R.; Massa, E.
1987-01-01
The 7th Italian Conference on General Relativity and Gravitational Physics was held in Rapallo (Genoa), from September 3 to 6, 1986, under the auspices of the International Society on General Relativity and Gravitation. Like the previous conferences of this series, it brought together physicists, mathematicians, and astronomers interested in various aspects of relativity, field theory, astrophysics, and cosmology. The scientific program included two types of sessions: invited lectures and workshops for presenting contributed papers. All these have been grouped into four main sections. The divisions are the following: A: General Relativity; B: Field Theory, Supergravity, and Strings; C: Relativistic Astrophysics and Cosmology; D: Experimental and Observational Relativity. This book presents the papers discussed in the meetings on the above mentioned subjects
International Nuclear Information System (INIS)
1997-08-01
The operational safety and reliability of a nuclear power plant as well as its availability for electricity generation depend on, among other things, its maintenance programme. Regulatory bodies therefore have considerable interest in maintenance activities. There are several approaches to maintenance, i.e. reliability centered maintenance or risk focused maintenance, aimed at optimizing maintenance by focusing on important components or systems. These approaches may result in significant changes to maintenance activities and therefore have to be considered for regulatory acceptance. In order to review and discuss the status of maintenance regulation in participating countries, the IAEA convened a Technical Committee Meeting on Regulatory Oversight of Maintenance Activities at Nuclear Power Plants in Vienna from 9 to 13 October 1995. The meeting was attended by 16 experts from 11 countries. In addition to the consideration of papers that were presented and which are reproduced here, extensive group and panel discussions took place during the meeting. These covered three main topics: general features and basic characteristics of maintenance regulation, regulatory acceptance of maintenance optimization and use of PSA for maintenance optimization. The discussion are summarized in Section 2. Section 3 discusses the following three additional topics: regulatory involvement in the maintenance programme, modifications to the maintenance programme and personnel related aspects of maintenance. The conclusions are presented in Section 4. Figs, tabs
Constraints on stress-energy perturbations in general relativity
International Nuclear Information System (INIS)
Traschen, J.
1985-01-01
Conditions are found for the existence of integral constraints on stress-energy perturbations in general relativity. The integral constraints can be thought of as a general-relativistic generalization of the conservation of energy and momentum of matter perturbations in special relativity. The constraints are stated in terms of a vector field V, and the Robertson-Walker spacetimes are shown to have such constraint vectors. Although in general V is not a Killing vector, in a vacuum spacetime the constraint vectors are precisely the Killing vectors
Indian Academy of Sciences (India)
The organization and arrangements for the scientific meetings, cultural event and the visits to Lothal and SAC were superb. The Academy is grateful to the Physical Research Laboratory particularly R K Varma, Director, PRL, to the. Institute for Plasma Research and its Director. P K Kaw, to the Space Applications Centre and.
Indian Academy of Sciences (India)
the Defence Minister, Government of India on some of his experiences in technology development in India. A summary of his lecture appears in this issue. In the afternoon the .... of steel armour for our Light Tank which has found wide application to meet the ... basic issues: how information is encoded in the structure of DNA ...
Indian Academy of Sciences (India)
1985-11-07
Nov 7, 1985 ... Business Meeting of Fellows. Evening Lecture. Architecture of the universe- R Cowsik ... and technical capabilities to plan, design and build satellites for earth observations, such as. Bhaskara I and II have ... Water Resources Systems Planning-. Some case studies for India. Edited by. Mahesh C Chaturvedi ...
On the relation of the generalized Schwarzschild metric and Tallman metric
International Nuclear Information System (INIS)
Sharshekeev, O.Sh.
1977-01-01
Relation of the Schwarzschild generalized metric (the Schwarzschild metric with regard for the four-dimension tensor of curvation) with the Tollman metric is considered. It is shown, that the Schwarzschild problem solution in the Tollman metric is quite correct as well. The obtained solutions meet the following requirements: conformity principle is carried out, transformation functional determinant is final everywhere, excluding the centre, where a singular point is to be
6th International Conference on the History of General Relativity
Eisenstaedt, Jean; The Universe of General Relativity; GR 6
2005-01-01
This volume from the Einstein Studies Series is based largely on papers presented at the Sixth International Conference on the History of General Relativity, held in Amsterdam on June 26-29, 2002. These contributions from notable experts offer both new and historical insights on gravitation, general relativity, cosmology, unified field theory, and the history of science. Topics discussed include the prehistory of special relativity, early attempts at a relativistic theory of gravitation, the beginnings of general relativity, the problem of motion in the context of relativity, conservation laws, the axiomatization of relativity, classical and contemporary cosmology, gravitation and electromagnetism, quantum gravity, and relativity as seen through the eyes of the public and renowned relativists. Contributors: K. Brading; G. Gale; H.F.M. Goenner; J. Goldberg; S. Katzir; D. Kennefick; H. Kragh; C. Lehner; U. Majer; J. Mattingly; E.T. Newman; J.D. Norton; J. Renn; R. Rynasiewicz; J.M. Sánchez-Ron; T. Sauer; C. Sm...
Does general relativity theory have the classical Newtonian limit limit
International Nuclear Information System (INIS)
Denisov, V.I.; Logunov, A.A.
1980-01-01
Newton gravitation theory and Newtonian approximation of the general relativity theory are considered. By the method of successive approximations Einstein equations have been solved and Newtonian approximation of the Einstein theory is obtained. It is shown that in general relativity theory there is no Newtonian limit for the integrals of the motion of matter and gravitational field, as the integrals of the motion of the Newton gravitation theory and Newtonian approximation of Einstein theory do not coincide. The Einstein general relativity theory is constructed at the cost of refusal of the conservation laws for energy-momentum of matter and gravitational field taken together
International Nuclear Information System (INIS)
Amano, Y.
2011-01-01
I am grateful for the opportunity to address this important gathering, which is taking place at a crucial time for the nuclear energy sector. I greatly value the experience and expertise of the World Association of Nuclear Operators and I welcome your decision to devote this biennial general meeting to the accident at the Fukushima Daiichi Nuclear Power Plant in Japan. Together, WANO and the IAEA will play a key role in ensuring that the right lessons are learned from the accident and that the necessary improvements in nuclear operating safety are actually put into practice everywhere. We have been good partners since WANO was created in 1989. In the aftermath of Fukushima Daiichi, I believe our partnership must be deepened and intensified. Since the Fukushima Daiichi accident, the IAEA has worked hard to help Japan bring the situation at the site under control and to mitigate the consequences of the accident. The Agency's view is that all of the crippled reactors are now generally stable. The Japanese authorities are doing their utmost to achieve cold shutdown of all of them by the end of the year. I visited Japan a number of times for consultations with the Prime Minister and government ministers and went to the site of the accident in July. I dispatched international expert teams to assist in areas such as radiological monitoring and food safety. The Agency helped to channel international technical assistance to Japan and we also provided independent and factual reports on the situation to our Member States. We conducted a number of fact-finding missions, most recently on environmental remediation and related waste management issues. I convened a special IAEA Ministerial Conference on Nuclear Safety, devoted to the Fukushima Daiichi accident, which took place in Vienna in June. The Conference adopted a Ministerial Declaration aimed at strengthening nuclear safety, emergency preparedness, and radiation protection of people and the environment worldwide. That
75 FR 7295 - National Council on Federal Labor-Management Relations Meeting
2010-02-18
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations will hold its initial meeting on February 26, 2010, at the time and location shown below. The Council is an advisory body composed of representatives of Federal employee...
75 FR 15463 - National Council on Federal Labor-Management Relations Meeting
2010-03-29
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations will hold its second and third meetings on April 7, 2010 and May 5... of Federal employee organizations, Federal management organizations, and senior government officials...
75 FR 22871 - National Council on Federal Labor-Management Relations Meeting
2010-04-30
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following dates-- Wednesday, June 2, 2010... is an advisory body composed of representatives of Federal employee organizations, Federal management...
78 FR 16715 - National Council on Federal Labor-Management Relations Meeting
2013-03-18
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following date-- Wednesday, May 15, 2013. The... Council is an advisory body composed of representatives of Federal employee organizations, Federal...
76 FR 80412 - National Council on Federal Labor-Management Relations Meeting
2011-12-23
... OFFICE OF PERSONNEL MANAGEMENT National Council on Federal Labor-Management Relations Meeting... Federal Labor-Management Relations plans to meet on the following dates: Wednesday, January 18, 2012... composed of representatives of Federal employee organizations, Federal management organizations, and senior...
General Theory of Relativity-The Power of Speculative Thought
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 4. General Theory of Relativity – The Power of Speculative Thought. Asit Banerjee. General Article Volume 11 Issue 4 April 2006 pp 45-55. Fulltext. Click here to view fulltext PDF. Permanent link:
General Relativity and the Accelerated Expansion of the Universe
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 3. General Relativity and the Accelerated Expansion of the Universe. Patrick Das Gupta. General Article Volume 17 Issue 3 March 2012 pp 254-273. Fulltext. Click here to view fulltext PDF. Permanent link:
HR Department
2010-01-01
Wednesday 29 September 2010 at 11h (160/1-009) Mr. Dimitri ARGYROPOULOS, Chairman of AMFIE's*) Board of Directors and Mrs. Janine RIVALS, Member of AMFIE's Board of Directors, will make a general presentation on AMFIE's personal financial services and how they may benefit international civil servants. They will also focus on the particular financial challenges faced by expatriate civil servants and on the solutions AMFIE can offer. The presentation will be followed by a question and answer session. Private consultations - 9:00 to 11:00 and 14:00 to 17:30 (5/1-030) Participants who wish to meet AMFIE's representatives for one-to-one private consultations are invited to contact directly Mrs. Janine Rivals (+33/1 45 35 70 79, GSM +33/6 63 58 36 62 or jr@amfie.org) or AMFIE's Secretariat in Luxembourg (+352/42 36 61-1 or amfie@amfie.org). A dedicated form will also be available for this purpose in the meeting room during the presentation. *)\tAMFIE is a cooperative society open exclusively to international ...
Gravitational duality in General Relativity and Supergravity theories
Energy Technology Data Exchange (ETDEWEB)
Dehouck, F. [Service de physique mathematique et interactions fondamentales. Universite Libre de Bruxelles, Campus Plaine CP-231, 1050 Bruxelles (Belgium)
2011-07-15
We quickly review the current status of gravitational duality in General Relativity. We summarize and comment some recent work on constructing dual (topological) charges and understanding how this duality acts in supergravity theories.
Can one tell Einstein's unimodular theory from Einstein's general relativity?
Alvarez, Enrique
2005-01-01
The so called unimodular theory of gravitation is compared with general relativity in the quadratic (Fierz-Pauli) regime, using a quite broad framework, and it is argued that quantum effects allow in principle to discriminate between both theories.
Conservation of particle-numbers in general relativity
Energy Technology Data Exchange (ETDEWEB)
Treder, H.J.
1975-12-01
If in a special relativistic field theory the particle number is an integral of a conservation law for a particle-current, then the conservation of the particle-number is valid in general relativity, too. (auth)
70 years of the general theory of relativity
International Nuclear Information System (INIS)
Castro Diaz-Balart, F.; Cabezas Solorzano, R.
1986-06-01
In view of the 70th anniversary of the discovery of the General Theory of Relativity, an analysis was made of the special and general theories. The basic postulates, their consequences in the formulation of the theories, the main results, some aspects related to the experimental verification and its applications are presented, as are some elements of the mathematical formalism of the theories, to facilitate the logical interrelationships between its results and consequences. (author)
The use of the algebraic programming in teaching general relativity
Ghergu, Florin A.; Vulcanov, Dumitru N.
1998-01-01
The article presents some aspects on the use of computer in teaching general relativity for undergraduate students with some experience in computer manipulation. The article presents some simple algebraic programming (in REDUCE+EXCALC package) procedures for obtaining and the study of some exact solutions of the Einstein equations in order to convince a dedicated student in general relativity about the utility of a computer algebra system.
Implications of a positive cosmological constant for general relativity
Ashtekar, Abhay
2017-10-01
Most of the literature on general relativity over the last century assumes that the cosmological constant Λ is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein’s equations with a small but positive Λ . Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, no matter how small Λ is. We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive Λ , focusing on gravitational waves.
Histories approach to general relativity: II. invariance groups
International Nuclear Information System (INIS)
Savvidou, Ntina
2004-01-01
In this paper we show in detail how the histories description of general relativity carries representations of both the spacetime diffeomorphism group and the Dirac algebra of constraints. We show that the introduction of metric-dependent equivariant foliations leads to the crucial result that the canonical constraints are invariant under the action of spacetime diffeomorphisms. Furthermore, there exists a representation of the group of generalized spacetime mappings that are functionals of the 4-metric: this is a spacetime analogue of the group originally defined by Bergmann and Komar in the context of the canonical formulation of general relativity. Finally, we discuss the possible directions for the quantization of gravity in histories theory
Implications of a positive cosmological constant for general relativity.
Ashtekar, Abhay
2017-10-01
Most of the literature on general relativity over the last century assumes that the cosmological constant [Formula: see text] is zero. However, by now independent observations have led to a consensus that the dynamics of the universe is best described by Einstein's equations with a small but positive [Formula: see text]. Interestingly, this requires a drastic revision of conceptual frameworks commonly used in general relativity, no matter how small [Formula: see text] is. We first explain why, and then summarize the current status of generalizations of these frameworks to include a positive [Formula: see text], focusing on gravitational waves.
Spinor formalism and complex-vector formalism of general relativity
International Nuclear Information System (INIS)
Han-ying, G.; Yong-shi, W.; Gendao, L.
1974-01-01
In this paper, using E. Cartan's exterior calculus, we give the spinor form of the structure equations, which leads naturally to the Newman--Penrose equations. Furthermore, starting from the spinor spaces and the el (2C) algebra, we construct the general complex-vector formalism of general relativity. We find that both the Cahen--Debever--Defrise complex-vector formalism and that of Brans are its special cases. Thus, the spinor formalism and the complex-vector formalism of general relativity are unified on the basis of the uni-modular group SL(2C) and its Lie algebra
The general class of the vacuum spherically symmetric equations of the general relativity theory
Energy Technology Data Exchange (ETDEWEB)
Karbanovski, V. V., E-mail: Karbanovski_V_V@mail.ru; Sorokin, O. M.; Nesterova, M. I.; Bolotnyaya, V. A.; Markov, V. N., E-mail: Markov_Victor@mail.ru; Kairov, T. V.; Lyash, A. A.; Tarasyuk, O. R. [Murmansk State Pedagogical University (Russian Federation)
2012-08-15
The system of the spherical-symmetric vacuum equations of the General Relativity Theory is considered. The general solution to a problem representing two classes of line elements with arbitrary functions g{sub 00} and g{sub 22} is obtained. The properties of the found solutions are analyzed.
The general theory of relativity a mathematical exposition
Das, Anadijiban
2012-01-01
The General Theory of Relativity: A Mathematical Exposition will serve readers as a modern mathematical introduction to the general theory of relativity. Throughout the book, examples, worked-out problems, and exercises (with hints and solutions) are furnished. Topics in this book include, but are not limited to: • tensor analysis • the special theory of relativity • the general theory of relativity and Einstein’s field equations • spherically symmetric solutions and experimental confirmations • static and stationary space-time domains • black holes • cosmological models • algebraic classifications and the Newman-Penrose equations • the coupled Einstein-Maxwell-Klein-Gordon equations • appendices covering mathematical supplements and special topics Mathematical rigor, yet very clear presentation of the topics make this book a unique text for both university students and research scholars. Anadijiban Das has taught courses on Relativity Theory at The University College of Dublin, Irelan...
IAEA specialists' meeting on the fusion evaluated nuclear data library related to the ITER activity
International Nuclear Information System (INIS)
Goulo, V.; Lorenz, A.
1988-01-01
This is the summary report of an IAEA Specialists' Meeting on the Fusion Evaluated Nuclear Data Library Related to the ITER Activity, convened by the IAEA Nuclear Data Section in Vienna from 16 to 18 November 1987. The objective of the meeting was to formulate a detailed programme and time schedule for the development of the Fusion Evaluated Nuclear Data Library (FENDL) to meet the future needs of the ITER activity
International Nuclear Information System (INIS)
1998-01-01
Though the majority of existing control and protection systems in nuclear power plants use old analogue technology and design philosophy, the use of computers in safety and safety related systems is becoming a current practice. The Specialists Meeting on ''Computerized Reactor Protection and Safety Related Systems in Nuclear Power Plants'' was organized by IAEA (jointly by the Division of Nuclear Power and the Fuel Cycle and the Division of Nuclear Installation Safety), in co-operation with Paks Nuclear Power Plant in Hungary and was held from 27-29 October 1997 in Budapest, Hungary. The meeting focused on computerized safety systems under refurbishment, software reliability issues, licensing experiences and experiences in implemented computerized safety and safety related systems. Within a meeting programme a technical visit to Paks NPP was organized. The objective of the meeting was to provide an international forum for the presentation and discussion on R and D, in-plant experiences in I and C important to safety, backfits and arguments for and reservations against the digital safety systems. The meeting was attended by 70 participants from 16 countries representing NPPs and utility organizations, design/engineering, research and development, and regulatory organizations. In the course of 4 sessions 25 technical presentations were made. The present volume contains the papers presented by national delegates and the conclusions drawn from the final general discussion
Relative Entropy and Variational Properties of Generalized Gibbsian Measures
Külske, Christof; Ny, Arnaud Le; Redig, Frank
2004-01-01
We study the relative entropy density for generalized Gibbs measures. We first show its existence and obtain a familiar expression in terms of entropy and relative energy for a class of “almost Gibbsian measures” (almost sure continuity of conditional probabilities). For quasilocal measures, we
Indefinite-metric quantum field theory of general relativity, 2
International Nuclear Information System (INIS)
Nakanishi, Noboru
1978-01-01
The canonical commutation relations are analyzed in detail in the manifestly covariant quantum field theory of general relativity proposed previously. It is explicitly proved that the BRS charge is indeed the generator of the BRS transformation both in the Landau gauge and in the non-Landau one. The equivalence between the field equations and the Heisenberg equations is confirmed. (author)
On the report of the Nuclear Energy Section Meeting, General Survey Committee
International Nuclear Information System (INIS)
Okamura, Shigehiro
1979-01-01
The demand and supply of petroleum have relaxed temporarily, but in the long run, the difficulty of energy problem does not change. More powerful promotion of general energy policy with conformity and effectiveness is a worldwide problem. In order to cope with such situation, General Energy Survey Committee has examined the concrete measures, and drawn up the interim report in August, 1977. The present report does not change from the interim report in its basic framework, but the background on which this framework is based is clarified, and the contents of the concrete measures are examined in more detail. The Nuclear Energy Sectional Meeting has obtained the conclusions about the basic matters in the development and utilization of nuclear energy and the concrete measures required to be taken urgently. The domestic and foreign situations about the development and utilization of nuclear energy are explained, and the location of nuclear power stations is the most serious bottleneck, therefore the measures to obtain national consensus are the most important problem in every country. The nuclear power generation in Japan is expected to reach 33 million kW by 1985 and 60 million kW by 1990. As the concrete measures, improvement of safety and reliability, establishment of nuclear fuel cycle, development and adoption of new type nuclear reactors, strengthening of the base of nuclear energy industries, promotion of research and development, and contribution to international activities are briefly discussed. (Kako, I.)
Generalization of Pain-Related Fear Based on Conceptual Knowledge.
Meulders, Ann; Vandael, Kristof; Vlaeyen, Johan W S
2017-05-01
Increasing evidence suggests that pain-related fear is key to the transition from acute to chronic pain. Previous research has shown that perceptual similarity with a pain-associated movement fosters the generalization of fear to novel movements. Perceptual generalization of pain-related fear is adaptive as it enables individuals to extrapolate the threat value of one movement to another without the necessity to learn anew. However, excessive spreading of fear to safe movements may become maladaptive and may lead to sustained anxiety, dysfunctional avoidance behaviors, and severe disability. A hallmark of human cognition is the ability to extract conceptual knowledge from a learning episode as well. Although this conceptual pathway may be important to understand fear generalization in chronic pain, research on this topic is lacking. We investigated acquisition and generalization of concept-based pain-related fear. During acquisition, unique exemplars of one action category (CS+; e.g., opening boxes) were followed by pain, whereas exemplars of another action category (CS-; e.g., closing boxes) were not. Subsequently, spreading of pain-related fear to novel exemplars of both action categories was tested. Participants learned to expect the pain to occur and reported more pain-related fear to the exemplars of the CS+ category compared with those of the CS- category. During generalization, fear and expectancy generalized to novel exemplars of the CS+ category, but not to the CS- category. This pattern was not corroborated in the eyeblink startle measures. This is the first study that demonstrates that pain-related fear can be acquired and generalized based on conceptual knowledge. Copyright © 2016. Published by Elsevier Ltd.
Brice, Maximilien
2016-01-01
His Excellency Mr. Andrius Krivas Ambassador and Permanent Representative of Republic of Lithuania signing the CERN Guest book with Director for International Relations C. Warakaulle and advisor C. Schaefer
A Semi-Tychonic Model in General relativity
Murphy, George L.
1998-10-01
In the sixteenth century Tycho Brahe proposed a geocentric model of the solar system kinematically equivalent to the heliocentric Copernican model. There has been disagreement even among prominent relativists over whether or not relativity validates use of a geocentric model. Tycho's desire for a non-rotating earth cannot be satisfied, but we demonstrate here dynamical equivalence between a Copernican and a "semi-Tychonic" model by using an appropriate accelerated reference frame in general relativity. (The idea of absolute space in Newtonian mechanics makes use of Einstein's theory desirable even in the Newtonian approximation.) Optical questions are easily dealt with. Our treatment provides a satisfactory answer for the important historical question concerning geocentric and heliocentric models, and is also of pedagogic value. In addition, it gives insights into the real generality of general relativity, the nature of the relativistic equations of motion, and the analogy between coordinate and gauge transformations.
The space-time of the bimetric general relativity theory
International Nuclear Information System (INIS)
Rosen, N.
1986-01-01
Previously, the author presented a report on the bimetric general relativity theory. Here he describes recent developments in this theory and discusses the space-time of the theory. The purpose of developing the bimetric general relativity theory is to try to remove some of the singularities that are present in the usual general relativity theory, such as those in cosmological models and in Schwarzschild solution. This is done by incorporating into the foundations of the theory the existence of a fundamental rest-frame in the universe. The author investigates the case of a completely collapsed star by considering the simplest equation of state which corresponds to Schwarzschild's interior solution of Einstein's equations
Introduction to general relativity, black holes and cosmology
Choquet-Bruhat, Yvonne
2015-01-01
General Relativity is a beautiful geometric theory, simple in its mathematical formulation but leading to numerous consequences with striking physical interpretations: gravitational waves, black holes, cosmological models, and so on. This introductory textbook is written for mathematics students interested in physics and physics students interested in exact mathematical formulations (or for anyone with a scientific mind who is curious to know more of the world we live in), recent remarkable experimental and observational results which confirm the theory are clearly described and no specialised physics knowledge is required. The mathematical level of Part A is aimed at undergraduate students and could be the basis for a course on General Relativity. Part B is more advanced, but still does not require sophisticated mathematics. Based on Yvonne Choquet-Bruhat's more advanced text, General Relativity and the Einstein Equations, the aim of this book is to give with precision, but as simply as possible, the found...
Gravitational radiation and the validity of general relativity
International Nuclear Information System (INIS)
Will, C.M.
2001-01-01
The regular observation of gravitational radiation by a world-wide network of resonant and laser-interferometric detectors will usher in a new form of astronomy. At the same time, it will provide new and interesting tests of general relativity. We review the current empirical status of general relativity, and discuss three areas in which direct observation of gravitational radiation could test the theory further: polarization of the waves, speed of the waves, and back-reaction of the waves on the evolution of the source. (author)
Canonical quantization of general relativity in discrete space-times.
Gambini, Rodolfo; Pullin, Jorge
2003-01-17
It has long been recognized that lattice gauge theory formulations, when applied to general relativity, conflict with the invariance of the theory under diffeomorphisms. We analyze discrete lattice general relativity and develop a canonical formalism that allows one to treat constrained theories in Lorentzian signature space-times. The presence of the lattice introduces a "dynamical gauge" fixing that makes the quantization of the theories conceptually clear, albeit computationally involved. The problem of a consistent algebra of constraints is automatically solved in our approach. The approach works successfully in other field theories as well, including topological theories. A simple cosmological application exhibits quantum elimination of the singularity at the big bang.
Using Algebraic Computing To Teach General Relativity And Cosmology
Vulcanov, Dumitru N.; Boată, Remus-Ştefan Ş.
2012-12-01
The article presents some new aspects and experience on the use of computer in teaching general relativity and cosmology for undergraduate students (and not only) with some experience in computer manipulation. Some years ago certain results were reported [1] using old fashioned computer algebra platforms but the growing popularity of graphical platforms as Maple and Mathematica forced us to adapt and reconsider our methods and programs. We will describe some simple algebraic programming procedures (in Maple with GrTensorII package) for obtaining and the study of some exact solutions of the Einstein equations in order to convince a dedicated student in general relativity about the utility of a computer algebra system.
On the mathematical theory of classical fields and general relativity
Klainerman, S
1993-01-01
From the perspective of an analyst, like myself, the General Theory of Relativity provides an extrordinary rich and vastly virgin territory. It is the aim of my lecture to provide, ﬁrst, an account of those aspects of the theory which attract me most and second a perspective of what has been accomplished so far in that respect. In trying to state our main objectives it helps to view General Relativity in the broader context of Classical Field Theory. EinsteiniVacuum equations, or shortly E—V, is already sufﬁciently complicated. I will thus restrict my attention to them.
The Eclipse to Confirm the General Theory of Relativity
Beléndez Vázquez, Augusto
2015-01-01
One of the milestones of the science of light commemorated during this International Year of Light and Light-based Technologies is “the embedding of light in cosmology through general relativity in 1915,” that is, the celebration of the centenary of Albert Einstein’s general theory of relativity. As Adolfo de Azcárraga, president of the Spanish Royal Physics Society (RSEF), points out in his book titled Albert Einstein, His Science and His Time, Einstein’s theory contained a spectacular predi...
Essays in general relativity a Festschrift for Abraham Taub
Tipler, Frank J
1981-01-01
Essays in General Relativity: A Festschrift for Abraham Taub is collection of essays to honor Professor Abraham H. Taub on the occasion of his retirement from the mathematics faculty of the University of California at Berkeley. Relativistic hydrodynamics has always been a subject dear to Taub's heart. In fact, many basic results on special relativistic fluid flows are due to him, and he has been a major contributor to the study of fluid flows near shocks. The book contains 16 chapters and begins with a discussion of a geometrical approach to general relativity. This is followed by separate cha
The revival of General Relativity at Princeton: Daring Conservatism
Brill Dieter; Blum Alexander
2018-01-01
After General Relativity was established in essentially its present form in 1915 it was celebrated as a great success of mathematical physics. But the initial hopes for this theory as a basis for all of physics began to fade in the next several decades, as General Relativity was relegated to the margins of theoretical physics. Its fate began to rise in the 1950's in a revival of interest and research that over time made gravitational physics one of the hottest research topics it is today. One...
Marriage Meets the Joneses: Relative Income, Identity, and Marital Status
Watson, Tara; McLanahan, Sara
2011-01-01
This paper investigates the effect of relative income on marriage. Accounting flexibly for absolute income, the ratio between a man's income and a local reference group median is a strong predictor of marital status, but only for low-income men. Relative income affects marriage even among those living with a partner. A 10 percent higher reference…
General relativity at 75: how right was einstein?
Will, C M
1990-11-09
The status of experimental tests of general relativity is reviewed on the occasion of its 75th anniversary. Einstein's equivalence principle is well supported by experiments such as the Eötvös experiment, tests of special relativity, and the gravitational redshift experiment. Tests of general relativity have reached high precision, including the light deflection and the perihelion advance of Mercury, proposed by Einstein 75 years ago, and new tests such as the Shapiro time delay and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected to an accuracy of 1 percent on the basis of measurements of the binary pulsar. The status of the "fifth force" is discussed, along with the frontiers of experimental relativity, including proposals for testing relativistic gravity with advanced technology and spacecraft.
Doppler frequency in interplanetary radar and general relativity
Mcvittie, G. C.
1972-01-01
The change of frequency of an interplanetary radar signal sent from the earth to another planet or to a space probe is worked out according to general relativity. The Schwarzschild spacetime is employed and its null geodesics control the motion of the signals. Exact Doppler frequency formulas are derived for one-way and two-way radar in terms of an arbitrary Schwarzschild radial coordinate. A reduction to the special relativity case is used to interpret the formulas in terms of the relative radial velocity of emitter and target. The general relativity corrections are worked out approximately for each of three possible Schwarzschild radial coordinates, and a numerical example is given. The amount of the correction is different according as one or the other of the Schwarzschild coordinates is identified with the radius vector deduced from classical celestial mechanics. The identification problem is discussed.
Equation of state and general relativity in supernovae
International Nuclear Information System (INIS)
Baron, E.A.
1985-01-01
The results of an extensive numerical study of the outcome of massive star collapse and subsequent shock formation and propagation are presented. The stiffness of the equation of state at high density is shown to play a crucial role, a softer equation of state being helpful to shock production and propagation. The effect of neutrinos is investigated in a simple manner by varying the neutrino transport from a simple trapping density to a simple leakage scheme. With a softer equation of state, the maximum central densities reached are high enough that general relativity may become important. The effects of general relativity are investigated in detail. It is shown that while general relativity is generally harmful to the shock, once the equation of state becomes soft enough, general relativistic effects may conspire to transfer large amounts of energy from the gravitational field to the shock, resulting in powerful explosions. This is first investigated using simplified initial conditions, the initial models being constructed in an ad hoc fashion to facilitate numerical investigation. Finally, results are presented for detailed pre-supernovae initial models of 12 and 15 M/sub sun/. These models do explode, with explosion energies varying from approx.1 - 3 x 10 51 ergs depending on the degree of softness of the high density equation of state
HR Department
2011-01-01
Monday 28 November 2011 at 12h (61/1-009 – Pas Perdus, room C) Mrs. Janine RIVALS, Vice-Chairwoman of AMFIE's* Board of Directors and Mrs. Hélène ECKERT, coordinator for all international organisations in Switzerland, will make a general presentation on AMFIE's personal financial services and how they may benefit international civil servants. They will also focus on the particular financial challenges faced by expatriate civil servants and on the solutions AMFIE can offer. The presentation will be followed by a question and answer session. Private consultations – from 11:00 to 12:00 and from 14:00 to 17:30 (61/1-009 and 61/0-006) Participants who wish to meet AMFIE's representatives for one-to-one private consultations are invited to contact directly Mrs. Janine Rivals (+33/1 45 35 70 79, GSM +33/6 63 58 36 62 or jr@amfie.org) or AMFIE's Secretariat in Luxembourg (+352/42 36 61-1 or amfie@amfie.org). It will be possible to make an ...
BOOK REVIEW: Partial Differential Equations in General Relativity
Halburd, Rodney G.
2008-11-01
Although many books on general relativity contain an overview of the relevant background material from differential geometry, very little attention is usually paid to background material from the theory of differential equations. This is understandable in a first course on relativity but it often limits the kinds of problems that can be studied rigorously. Einstein's field equations lie at the heart of general relativity. They are a system of partial differential equations (PDEs) relating the curvature of spacetime to properties of matter. A central part of most problems in general relativity is to extract information about solutions of these equations. Most standard texts achieve this by studying exact solutions or numerical and analytical approximations. In the book under review, Alan Rendall emphasises the role of rigorous qualitative methods in general relativity. There has long been a need for such a book, giving a broad overview of the relevant background from the theory of partial differential equations, and not just from differential geometry. It should be noted that the book also covers the basic theory of ordinary differential equations. Although there are many good books on the rigorous theory of PDEs, methods related to the Einstein equations deserve special attention, not only because of the complexity and importance of these equations, but because these equations do not fit into any of the standard classes of equations (elliptic, parabolic, hyperbolic) that one typically encounters in a course on PDEs. Even specifying exactly what ones means by a Cauchy problem in general relativity requires considerable care. The main problem here is that the manifold on which the solution is defined is determined by the solution itself. This means that one does not simply define data on a submanifold. Rendall's book gives a good overview of applications and results from the qualitative theory of PDEs to general relativity. It would be impossible to give detailed
Indefinite-metric quantum field theory of general relativity
International Nuclear Information System (INIS)
Nakanishi, Noboru
1978-01-01
Quantum field theory of Einstein's general relativity is formulated in the indefinitemetric Hilbert space in such a way that asymptotic fields are manifestly Lorentz covariant and the physical S-matrix is unitary. The general coordinate transformation is transcribed into a q-number transformation, called the BRS transformation. Its abstract definition is presented on the basis of the BRS transformation for the Yang-Mills theory. The BRS transformation for general relativity is then explicitly constructed. The gauge-fixing Lagrangian density and the Faddeev-Popov one are introduced in such a way that their sum behaves like a scalar density under the BRS transformation. One can then proceed in the same way as in the Kugo-Ojima formalism of the Yang-Mills theory to establish the unitarity of the physical S-matrix. (author)
Collineations of the curvature tensor in general relativity
Indian Academy of Sciences (India)
physics pp. 43–48. Collineations of the curvature tensor in general relativity. RISHI KUMAR TIWARI. Department of Mathematics and Computer Application, ... and kinematical properties of the models. Keywords. Collineation; Killing vectors; Ricci tensor; Riemannian curvature tensor. PACS No. 98.80. 1. Introduction.
Einstein and Hilbert: The creation of general relativity
International Nuclear Information System (INIS)
Todorov, I.T.
1992-12-01
It took eight years after Einstein announced the basic physical ideas behind the relativistic gravity theory before the proper mathematical formulation of general-relativity was mastered. The efforts of the greatest physicist and of the greatest mathematician of the time was involved and reached a breathtaking concentration during the last month of the work. (author)
Related General-Vocabulary Knowledge Transfers to Learning Technical Terms
Balch, William R.
2015-01-01
In a classroom experiment during the first week of an introductory psychology course, randomly assigned students received a pretest and then a brief training on the definitions of general-vocabulary words either related (e.g., "facilitation") or unrelated (e.g., "rendition") to 16 technical terms (e.g., "social…
Albert Einstein's 1916 Review Article on General Relativity
Sauer, Tilman
2004-01-01
The first comprehensive overview of the final version of the general theory of relativity was published by Einstein in 1916 after several expositions of preliminary versions and latest revisions of the theory in November 1915. A historical account of this review paper is given, of its prehistory, including a discussion of Einstein's collaboration with Marcel Grossmann, and of its immediate reception.
Collineations of the curvature tensor in general relativity
Indian Academy of Sciences (India)
The general theory of relativity, which is a field theory of gravitation, is described by the Einstein field equations. These equations whose fundamental constituent is the space-time metric gij, are highly non-linear partial differential equations and, therefore it is very difficult to obtain exact solutions. They become still more diffi-.
Survey on Dirac equation in general relativity theory
International Nuclear Information System (INIS)
Paillere, P.
1984-10-01
Starting from an infinitesimal transformation expressed with a Killing vector and using systematically the formalism of the local tetrades, we show that, in the area of the general relativity, the Dirac equation may be formulated only versus the four local vectors which determine the gravitational potentials, their gradients and the 4-vector potential of the electromagnetic field [fr
Refinements, Generalizations, and Applications of Jordan's Inequality and Related Problems
Directory of Open Access Journals (Sweden)
Feng Qi
2009-01-01
Full Text Available This is a survey and expository article. Some new developments on refinements, generalizations, and applications of Jordan's inequality and related problems, including some results about Wilker-Anglesio's inequality, some estimates for three kinds of complete elliptic integrals, and several inequalities for the remainder of power series expansion of the exponential function, are summarized.
Generalized virial relations and the theory of subdynamics
International Nuclear Information System (INIS)
Obcemea, Ch.; Froelich, P.; Braandas, E.J.
1981-05-01
In this paper, we discuss the implication of the generalized virial relations in the spectral analysis of Liouville operators. In particular, we refer to the existence problem of the analytic continuation of these super-operators and their resolvents occurring in the reduced dynamics description of open systems. For completeness, we outline the main ideas of the subdynamics approach. (author)
On the Possibility of Supertasks in General Relativity
Manchak, John Byron
2010-03-01
Malament-Hogarth spacetimes are the sort of models within general relativity that seem to allow for the possibility of supertasks. There are various ways in which these spacetimes might be considered physically problematic. Here, we examine these criticisms and investigate the prospect of escaping them.
On the quantization of general relativity in anholonomic variables
v. Borzeszkowski, H.-H.; de Sabbata, V.; Sivaram, C.; Treder, H.-J.
1996-04-01
In discussing Bohr-Sommerfeld-like quantum rules for gravity, it is argued that Einstein's Riemannian theory of general relativity rather leads to a quantum field-mechanics than to a quantum-field theory of gravity. We construct the canonically conjugate coordinates and momenta of this gravito-dynamics in the framework of the Einstein-Cartan teleparallelism.
Nuclear equation of state, general relativity and supernovae explosions
International Nuclear Information System (INIS)
Kahana, S.
1985-01-01
Prompt explosions are obtained in hydrodynamic simulations for the 12 Msub solar and 15 Msub solar type II supernova initial models of Weaver and Woosley, when the nuclear equation of state is sufficiently soft and when general relativity is included. 12 refs
Bianchi type-V string cosmological models in general relativity
Indian Academy of Sciences (India)
Abstract. Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's field equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's field equations are solvable for any arbitrary ...
Probing Students' Understanding of Some Conceptual Themes in General Relativity
Bandyopadhyay, Atanu; Kumar, Arvind
2010-01-01
This work is an attempt to see how physics undergraduates view the basic ideas of general relativity when they are exposed to the topic in a standard introductory course. Since the subject is conceptually and technically difficult, we adopted a "case studies" approach, focusing in depth on about six students who had just finished a one semester…
Bianchi type I inflationary universe in general relativity
Indian Academy of Sciences (India)
Bianchi type I inflationary universe in general relativity. RAJ BALI and VIMAL CHAND JAIN. Department of Mathematics, University of Rajasthan, Jaipur 302 004, India. MS received 4 May 1998; revised 24 July 2001. Abstract. In this paper, we have investigated Bianchi type I inflationary universe in the presence of massless ...
Bianchi type IX string cosmological model in general relativity
Indian Academy of Sciences (India)
Abstract. We have investigated Bianchi type IX string cosmological models in general relativity. To get a determinate solution, we have assumed a condition p = λ i.e. rest energy density for a cloud of strings is equal to the string tension density. The various physical and geometrical aspects of the models are also discussed.
Statistical equilibrium and symplectic geometry in general relativity
International Nuclear Information System (INIS)
Iglesias, P.
1981-09-01
A geometrical construction is given of the statistical equilibrium states of a system of particles in the gravitational field in general relativity. By a method of localization variables, the expression of thermodynamic values is given and the compatibility of this description is shown with a macroscopic model of a relativistic continuous medium for a given value of the free-energy function [fr
Galileons as the Scalar Analogue of General Relativity
Klein, Remko; Ozkan, Mehmet; Roest, Diederik
2016-01-01
We establish a correspondence between general relativity with diffeomorphism invariance and scalar field theories with Galilean invariance: notions such as the Levi-Civita connection and the Riemann tensor have a Galilean counterpart. This suggests Galilean theories as the unique nontrivial
Bianchi type IX string cosmological model in general relativity
Indian Academy of Sciences (India)
We have investigated Bianchi type IX string cosmological models in general relativity. To get a determinate solution, we have assumed a condition ρ= i.e. rest energy density for a cloud of strings is equal to the string tension density. The various physical and geometrical aspects of the models are also discussed.
Bianchi type-V string cosmological models in general relativity
Indian Academy of Sciences (India)
Bianchi type-V string cosmological models in general relativity are investigated. To get the exact solution of Einstein's ﬁeld equations, we have taken some scale transformations used by Camci et al [Astrophys. Space Sci. 275, 391 (2001)]. It is shown that Einstein's ﬁeld equations are solvable for any arbitrary cosmic scale ...
The general theory of relativity: the first thirty years
International Nuclear Information System (INIS)
Chandrasekhar, S.
1980-01-01
The principal landmarks in the development of general relativity (exclusive of cosmology) during the first 30 years after its founding are presented. The emergence of the new gravitational laws, their experimental consequences and the consequent growth of the present concern with gravitational collapse and black holes are traced. (U.K.)
On stability relative to vector elements of the orbit in general relativity motion
International Nuclear Information System (INIS)
Abdil'din, M.M.; Bejsenova, N.A.
2002-01-01
In this work a question of a new type of stability - stability relative to vector elements of the orbit is considered in general relativity mechanics in case of the Lenze-Thirring and two body rotation. (author)
2016-05-01
A scientific session of the General meeting of the Physical Sciences Division of the Russian Academy of Sciences (RAS) was held in the conference hall of the Lebedev Physical Institute, RAS on 7 December 2015. The papers collected in this issue were written based on talks given at the session (the program of the session is available on the RAS Physical Sciences Division website http://www.gpad.ac.ru). (1) Loshchenov V B (Prokhorov General Physics Institute, RAS, Moscow) "Pharmacodynamics of a nanophotosensitizer under irradiation by an electromagnetic field: from THz to Cherenkov radiation"; (2) Zhuikov B L (Institute for Nuclear Research, RAS, Moscow) "Successes and problems in the development of medical radioisotope production in Russia"; (3) Tikhonov Yu A (Budker Institute of Nuclear Physics, SB RAS, Novosibirsk) "Applying nuclear physics methods in healthcare"; (4) Turchin I V (Institute of Applied Physics, RAS, Nizhny Novgorod) "Methods of biomedical optical imaging: from subcellular structures to tissues and organs"; (5) Breus T K, Petrukovich A A (Space Research Institute, RAS, Moscow), Binhi V N (Prokhorov General Physics Institute, RAS, Moscow; Lomonosov Moscow State University, Moscow) "Magnetic factor in solar-terrestrial relations and its impact on the human body: physical problems and prospects for research"; (6) Makarov D I (Special Astrophysical Observatory, RAS, Nizhnii Arkhyz, Zelenchukskii region, Karachai-Cherkessian Republic) "Studying the Local University". Papers based on oral reports 2, 4, and 5 are presented below. • Successes and problems in the development of medical radioisotope production in Russia, B L Zhuikov Physics-Uspekhi, 2016, Volume 59, Number 5, Pages 481-486 • Methods of biomedical optical imaging: from subcellular structures to tissues and organs, I V Turchin Physics-Uspekhi, 2016, Volume 59, Number 5, Pages 487-501 • Magnetic factor in solar-terrestrial relations and its impact on the human body: physical problems and
Simien, Ki Eisha
2017-01-01
The purpose of this basic qualitative study was to uncover and understand secondary general school educators' experiences and perspectives in readiness in meeting the needs of high functioning autism spectrum disorder (HFASD) learners within the inclusive teaching environment. The research question served as the foundational premise of the…
Comparison of Einstein-Boltzmann solvers for testing general relativity
Bellini, E.; Barreira, A.; Frusciante, N.; Hu, B.; Peirone, S.; Raveri, M.; Zumalacárregui, M.; Avilez-Lopez, A.; Ballardini, M.; Battye, R. A.; Bolliet, B.; Calabrese, E.; Dirian, Y.; Ferreira, P. G.; Finelli, F.; Huang, Z.; Ivanov, M. M.; Lesgourgues, J.; Li, B.; Lima, N. A.; Pace, F.; Paoletti, D.; Sawicki, I.; Silvestri, A.; Skordis, C.; Umiltà, C.; Vernizzi, F.
2018-01-01
We compare Einstein-Boltzmann solvers that include modifications to general relativity and find that, for a wide range of models and parameters, they agree to a high level of precision. We look at three general purpose codes that primarily model general scalar-tensor theories, three codes that model Jordan-Brans-Dicke (JBD) gravity, a code that models f (R ) gravity, a code that models covariant Galileons, a code that models Hořava-Lifschitz gravity, and two codes that model nonlocal models of gravity. Comparing predictions of the angular power spectrum of the cosmic microwave background and the power spectrum of dark matter for a suite of different models, we find agreement at the subpercent level. This means that this suite of Einstein-Boltzmann solvers is now sufficiently accurate for precision constraints on cosmological and gravitational parameters.
Maladaptive Core Beliefs and their Relation to Generalized Anxiety Disorder.
Koerner, Naomi; Tallon, Kathleen; Kusec, Andrea
2015-01-01
Research has demonstrated that individuals with generalized anxiety disorder (GAD) hold unhelpful beliefs about worry, uncertainty, and the problem-solving process. Extant writings (e.g., treatment manuals) also suggest that other types of maladaptive beliefs may characterize those with GAD. However, these other beliefs have received limited empirical attention and are not an explicit component of cognitive theories of GAD. The present study examined the extent to which dysfunctional attitudes, early maladaptive schemas, and broad self-focused and other-focused beliefs explain significant variance in GAD symptoms, over and above negative and positive beliefs about worry, negative beliefs about uncertainty, and negative beliefs about problems. N = 138 participants classified into Probable GAD and Non-GAD groups completed self-report measures. After controlling for trait anxiety and depressive symptoms, only beliefs about worry, negative beliefs about uncertainty, and schemas reflecting unrelenting standards (e.g., "I must meet all my responsibilities all the time"), the need to self-sacrifice (e.g., "I'm the one who takes care of others"), and less positive views of other people and their intentions (e.g., lower endorsement of views such as "other people are fair"), were unique correlates of Probable GAD versus Non-GAD or GAD severity. Theoretical and clinical implications are discussed.
Noncommutative unification of general relativity and quantum mechanics
International Nuclear Information System (INIS)
Heller, Michael; Pysiak, Leszek; Sasin, Wieslaw
2005-01-01
We present a model unifying general relativity and quantum mechanics based on a noncommutative geometry. This geometry is developed in terms of a noncommutative algebra A which is defined on a transformation groupoid Γ given by the action of a noncompact group G on the total space E of a principal fiber bundle over space-time M. The case is important since to obtain physical effects predicted by the model we should assume that G is a Lorentz group or some of its representations. We show that the generalized Einstein equation of the model has the form of the eigenvalue equation for the generalized Ricci operator, and all relevant operators in the quantum sector of the model are random operators; we study their dynamics. We also show that the model correctly reproduces general relativity and the usual quantum mechanics. It is interesting that the latter is recovered by performing the measurement of any observable. In the act of such a measurement the model 'collapses' to the usual quantum mechanics
Isotropic extensions of the vacuum solutions in general relativity
Energy Technology Data Exchange (ETDEWEB)
Molina, C. [Universidade de Sao Paulo (USP), SP (Brazil); Martin-Moruno, Prado [Victoria University of Wellington (New Zealand); Gonzalez-Diaz, Pedro F. [Consejo Superior de Investigaciones Cientificas, Madrid (Spain)
2012-07-01
Full text: Spacetimes described by spherically symmetric solutions of Einstein's equations are of paramount importance both in astrophysical applications and theoretical considerations. And among those, black holes are highlighted. In vacuum, Birkhoff's theorem and its generalizations to non-asymptotically flat cases uniquely fix the metric as the Schwarzschild, Schwarzschild-de Sitter or Schwarzschild-anti-de Sitter geometries, the vacuum solutions of the usual general relativity with zero, positive or negative values for the cosmological constant, respectively. In this work we are mainly interested in black holes in a cosmological environment. Of the two main assumptions of the cosmological principle, homogeneity is lost when compact objects are considered. Nevertheless isotropy is still possible, and we enforce this condition. Within this context, we investigate spatially isotropic solutions close - continuously deformable - to the usual vacuum solutions. We obtain isotropic extensions of the usual spherically symmetric vacuum geometries in general relativity. Exact and perturbative solutions are derived. Maximal extensions are constructed and their causal structures are discussed. The classes of geometries obtained include black holes in compact and non-compact universes, wormholes in the interior region of cosmological horizons, and anti-de Sitter geometries with excess/deficit solid angle. The tools developed here are applicable in more general contexts, with extensions subjected to other constraints. (author)
General Theory of Relativity: Will It Survive the Next Decade?
Bertolami, Orfeu; Paramos, Jorge; Turyshev, Slava G.
2006-01-01
The nature of gravity is fundamental to our understanding of our own solar system, the galaxy and the structure and evolution of the Universe. Einstein's general theory of relativity is the standard model that is used for almost ninety years to describe gravitational phenomena on these various scales. We review the foundations of general relativity, discuss the recent progress in the tests of relativistic gravity, and present motivations for high-accuracy gravitational experiments in space. We also summarize the science objectives and technology needs for the laboratory experiments in space with laboratory being the entire solar system. We discuss the advances in our understanding of fundamental physics anticipated in the near future and evaluate discovery potential for the recently proposed gravitational experiments.
A century of general relativity: astrophysics and cosmology.
Blandford, R D
2015-03-06
One hundred years after its birth, general relativity has become a highly successful physical theory in the sense that it has passed a large number of experimental and observational tests and finds extensive application to a wide variety of cosmic phenomena. It remains an active area of research as new tests are on the way, epitomized by the exciting prospect of detecting gravitational waves from merging black holes. General relativity is the essential foundation of the standard model of cosmology and underlies our description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. Its interface with physics on the smallest and largest scales will continue to provide fertile areas of investigation in its next century. Copyright © 2015, American Association for the Advancement of Science.
Testing General Relativity with the Shadow Size of Sgr A(*).
Johannsen, Tim; Broderick, Avery E; Plewa, Philipp M; Chatzopoulos, Sotiris; Doeleman, Sheperd S; Eisenhauer, Frank; Fish, Vincent L; Genzel, Reinhard; Gerhard, Ortwin; Johnson, Michael D
2016-01-22
In general relativity, the angular radius of the shadow of a black hole is primarily determined by its mass-to-distance ratio and depends only weakly on its spin and inclination. If general relativity is violated, however, the shadow size may also depend strongly on parametric deviations from the Kerr metric. Based on a reconstructed image of Sagittarius A^{*} (Sgr A^{*}) from a simulated one-day observing run of a seven-station Event Horizon Telescope (EHT) array, we employ a Markov chain Monte Carlo algorithm to demonstrate that such an observation can measure the angular radius of the shadow of Sgr A^{*} with an uncertainty of ∼1.5 μas (6%). We show that existing mass and distance measurements can be improved significantly when combined with upcoming EHT measurements of the shadow size and that tight constraints on potential deviations from the Kerr metric can be obtained.
Relations between task delegation and job satisfaction in general practice
DEFF Research Database (Denmark)
Riisgaard, Helle; Nexøe, Jørgen; Videbæk Le, Jette
2016-01-01
task delegation and general practitioners' and their staff's job satisfaction and, additionally, 2) to review the evidence of possible explanations for this relation. METHODS: A systematic literature review. We searched the four databases PubMed, Cinahl, Embase, and Scopus systematically. The immediate...... practitioners' and their staff's job satisfaction appears to be sparse even though job satisfaction is acknowledged as an important factor associated with both patient satisfaction and medical quality of care. Therefore, the overall aim of this study was 1) to review the current research on the relation between...... attitude towards task delegation was positive and led to increased job satisfaction, probably because task delegation comprised a high degree of work autonomy. CONCLUSIONS: The few studies included in our review suggest that task delegation within general practice may be seen by the staff as an overall...
Even-dimensional General Relativity from Born–Infeld gravity
Energy Technology Data Exchange (ETDEWEB)
Concha, P.K.; Peñafiel, D.M.; Rodríguez, E.K.; Salgado, P., E-mail: pasalgad@udec.cl
2013-10-01
It is an accepted fact that requiring the Lovelock theory to have the maximum possible number of degree of freedom, fixes the parameters in terms of the gravitational and the cosmological constants. In odd dimensions, the Lagrangian is a Chern–Simons form for the (A)dS group. In even dimensions, the action has a Born–Infeld-like form. Recently was shown that standard odd-dimensional General Relativity can be obtained from Chern–Simons gravity theory for a certain Lie algebra B. Here we report on a simple model that suggests a mechanism by which standard even-dimensional General Relativity may emerge as a weak coupling constant limit of a Born–Infeld theory for a certain Lie subalgebra of the algebra B. Possible extension to the case of even-dimensional supergravity is briefly discussed.
Academic Training: Einstein and beyond: Introduction to General relativity
Françoise Benz
2005-01-01
2005-2006 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 3, 4, 5, 6, 7 October from 11:00 to 12:00 - Main Auditorium, bldg. 500 Einstein and beyond: Introduction to General relativity by N. Straumann / Institut fur theoretische physics, Univ. Zürich We review the enduring achievements of Einstein's papers of 1905 and their impact on the further developments in physics. Program : Lectures I and II:Einstein's Contributions to Statistical Mechanics and Quantum Theory Lecture III:Einstein's Thesis at the University of Zürich Lecture IV: From Special to General Relativity Lecture V: The History and the Mystery of the Cosmological Constant ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch
Relations between task delegation and job satisfaction in general practice
DEFF Research Database (Denmark)
Riisgaard, Helle; Nexøe, Jørgen; Videbæk Le, Jette
2016-01-01
practitioners' and their staff's job satisfaction appears to be sparse even though job satisfaction is acknowledged as an important factor associated with both patient satisfaction and medical quality of care. Therefore, the overall aim of this study was 1) to review the current research on the relation between...... task delegation and general practitioners' and their staff's job satisfaction and, additionally, 2) to review the evidence of possible explanations for this relation. METHODS: A systematic literature review. We searched the four databases PubMed, Cinahl, Embase, and Scopus systematically. The immediate...... attitude towards task delegation was positive and led to increased job satisfaction, probably because task delegation comprised a high degree of work autonomy. CONCLUSIONS: The few studies included in our review suggest that task delegation within general practice may be seen by the staff as an overall...
Testing general relativity at cosmological scales: Implementation and parameter correlations
International Nuclear Information System (INIS)
Dossett, Jason N.; Ishak, Mustapha; Moldenhauer, Jacob
2011-01-01
The testing of general relativity at cosmological scales has become a possible and timely endeavor that is not only motivated by the pressing question of cosmic acceleration but also by the proposals of some extensions to general relativity that would manifest themselves at large scales of distance. We analyze here correlations between modified gravity growth parameters and some core cosmological parameters using the latest cosmological data sets including the refined Cosmic Evolution Survey 3D weak lensing. We provide the parametrized modified growth equations and their evolution. We implement known functional and binning approaches, and propose a new hybrid approach to evolve the modified gravity parameters in redshift (time) and scale. The hybrid parametrization combines a binned redshift dependence and a smooth evolution in scale avoiding a jump in the matter power spectrum. The formalism developed to test the consistency of current and future data with general relativity is implemented in a package that we make publicly available and call ISiTGR (Integrated Software in Testing General Relativity), an integrated set of modified modules for the publicly available packages CosmoMC and CAMB, including a modified version of the integrated Sachs-Wolfe-galaxy cross correlation module of Ho et al. and a new weak-lensing likelihood module for the refined Hubble Space Telescope Cosmic Evolution Survey weak gravitational lensing tomography data. We obtain parameter constraints and correlation coefficients finding that modified gravity parameters are significantly correlated with σ 8 and mildly correlated with Ω m , for all evolution methods. The degeneracies between σ 8 and modified gravity parameters are found to be substantial for the functional form and also for some specific bins in the hybrid and binned methods indicating that these degeneracies will need to be taken into consideration when using future high precision data.
Introduction to General Relativity and Black Holes (2/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (4/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (3/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (5/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Introduction to General Relativity and Black Holes (1/5)
CERN. Geneva
2001-01-01
Conceptual foundations of General Relativity (GR). Uniqueness of GR. Mathematical framework: tensor calculus, Riemannian geometry, connection, 'spin' connection, curvature, Cartan's form calculus. Hilbert-Einstein action, Einstein equations. Weak gravitational fields. Post Newtonian Approximation. Gravitanional Waves. Exact solutions. Killing vectors. Experimental tests. Black Holes: extensions of the Schwarzschild solution; Kerr-Newman holes; no-hair theorems; energtics of black holes; the membrane approach; quantum mechanics of black holes; Bekenstein entropy; Hawking temperature; black holes and string theory.
Canonical perturbation theory in linearized general relativity theory
International Nuclear Information System (INIS)
Gonzales, R.; Pavlenko, Yu.G.
1986-01-01
Canonical perturbation theory in linearized general relativity theory is developed. It is shown that the evolution of arbitrary dynamic value, conditioned by the interaction of particles, gravitation and electromagnetic fields, can be presented in the form of a series, each member of it corresponding to the contribution of certain spontaneous or induced process. The main concepts of the approach are presented in the approximation of a weak gravitational field
The role of general relativity in the uncertainty principle
International Nuclear Information System (INIS)
Padmanabhan, T.
1986-01-01
The role played by general relativity in quantum mechanics (especially as regards the uncertainty principle) is investigated. It is confirmed that the validity of time-energy uncertainty does depend on gravitational time dilation. It is also shown that there exists an intrinsic lower bound to the accuracy with which acceleration due to gravity can be measured. The motion of equivalence principle in quantum mechanics is clarified. (author)
Entanglement entropy from surface terms in general relativity
Bhattacharyya, Arpan; Sinha, Aninda
2013-01-01
Entanglement entropy in local quantum field theories is typically ultraviolet divergent due to short distance effects in the neighbourhood of the entangling region. In the context of gauge/gravity duality, we show that surface terms in general relativity are able to capture this entanglement entropy. In particular, we demonstrate that for 1+1 dimensional CFTs at finite temperature whose gravity dual is the BTZ black hole, the Gibbons-Hawking-York term precisely reproduces the entanglement ent...
General relativity from three-forms in seven dimensions
Directory of Open Access Journals (Sweden)
Kirill Krasnov
2017-09-01
Full Text Available We consider a certain theory of 3-forms in 7 dimensions, and study its dimensional reduction to 4D, compactifying the 7-dimensional manifold on the 3-sphere of a fixed radius. We show that the resulting 4D theory is (Riemannian General Relativity (GR in Plebanski formulation, modulo corrections that are negligible for curvatures smaller than Planckian. Possibly the most interesting point of this construction is that the dimensionally reduced theory is GR with a non-zero cosmological constant, and the value of the cosmological constant is directly related to the size of S3. Realistic values of Λ correspond to S3 of Planck size.
Gravitation experiments at Stanford. [using general relativity theory
Lipa, J. A.
1980-01-01
The experimental situation in post-Newtonian gravitation is briefly reviewed in order to reexamine the extent to which experiment supports or refutes general relativity. A description is given of the equivalence principle project, the gyroscope experiment, and the search for gravity waves. It is noted that even though some doubt has been cast on the value of the perihelion advance and the gravitational redshift as precise tests of general relativity in the past few years, many competing theories have been ruled out; in particular, the results from the Viking mission significantly reduce the credibility of the Brans-Dicke theory (Brans and Dicke, 1961). The dimensionless constant omega in this theory is now forced to exceed 50, while the value originally proposed was 6 (omega being infinity in general relativity). It is noted that the gyro experiment described is capable of putting much tighter limits on this parameter, and together with the other experiments in progress will help place gravitational theory on a firmer experimental footing.
Explanatory and illustrative visualization of special and general relativity.
Weiskopf, Daniel; Borchers, Marc; Ertl, Thomas; Falk, Martin; Fechtig, Oliver; Frank, Regine; Grave, Frank; King, Andreas; Kraus, Ute; Müller, Thomas; Nollert, Hans-Peter; Rica Mendez, Isabel; Ruder, Hanns; Schafhitzel, Tobias; Schär, Sonja; Zahn, Corvin; Zatloukal, Michael
2006-01-01
This paper describes methods for explanatory and illustrative visualizations used to communicate aspects of Einstein's theories of special and general relativity, their geometric structure, and of the related fields of cosmology and astrophysics. Our illustrations target a general audience of laypersons interested in relativity. We discuss visualization strategies, motivated by physics education and the didactics of mathematics, and describe what kind of visualization methods have proven to be useful for different types of media, such as still images in popular science magazines, film contributions to TV shows, oral presentations, or interactive museum installations. Our primary approach is to adopt an egocentric point of view: The recipients of a visualization participate in a visually enriched thought experiment that allows them to experience or explore a relativistic scenario. In addition, we often combine egocentric visualizations with more abstract illustrations based on an outside view in order to provide several presentations of the same phenomenon. Although our visualization tools often build upon existing methods and implementations, the underlying techniques have been improved by several novel technical contributions like image-based special relativistic rendering on GPUs, special relativistic 4D ray tracing for accelerating scene objects, an extension of general relativistic ray tracing to manifolds described by multiple charts, GPU-based interactive visualization of gravitational light deflection, as well as planetary terrain rendering. The usefulness and effectiveness of our visualizations are demonstrated by reporting on experiences with, and feedback from, recipients of visualizations and collaborators.
Twenty-sixth general conference meeting of representatives of RCA member states. Report
International Nuclear Information System (INIS)
1997-10-01
The meeting discussed the following issues: RCA Annual Report 1996; Report of the 19th RCA Working Group Meeting, Yangon Myanmar, 10-14 March 1997; RCA in the next 25 years; Development finance and the RCA; locating a senior RCA representative in the region; RCA guidelines and operating rules; TCDC activities; terminal tripartite review meeting on UNDP/RCA/IAEA project; status of new joint UNDP/RCA/IAEA project; options for the new joint project; RCA activities and budget in 1997 and 1998; reformulation and health care project; RCA proposed programme for 1999-2000; country statements; extension of RCA agreement; RCA 25th anniversary; venue and date of the 20th regular meeting of national RCA representatives
Standard general relativity from Chern-Simons gravity
International Nuclear Information System (INIS)
Izaurieta, F.; Minning, P.; Perez, A.; Rodriguez, E.; Salgado, P.
2009-01-01
Chern-Simons models for gravity are interesting because they provide a truly gauge-invariant action principle in the fiber-bundle sense. So far, their main drawback has largely been its perceived remoteness from standard General Relativity, based on the presence of higher powers of the curvature in the Lagrangian (except, remarkably, for three-dimensional spacetime). Here we report on a simple model that suggests a mechanism by which standard General Relativity in five-dimensional spacetime may indeed emerge at a special critical point in the space of couplings, where additional degrees of freedom and corresponding 'anomalous' Gauss-Bonnet constraints drop out from the Chern-Simons action. To achieve this goal, both the Lie algebra g and the symmetric g-invariant tensor that define the Chern-Simons Lagrangian are constructed by means of the Lie algebra S-expansion method with a suitable finite Abelian semigroup S. The results are generalized to arbitrary odd dimensions, and the possible extension to the case of eleven-dimensional supergravity is briefly discussed.
Gauge stability of 3+1 formulations of general relativity
International Nuclear Information System (INIS)
Khokhlov, A M; Novikov, I D
2002-01-01
We present a general approach to the analysis of gauge stability of 3+1 formulations of general relativity (GR). Evolution of coordinate perturbations and the corresponding perturbations of lapse and shift can be described by a system of eight quasi-linear partial differential equations. Stability with respect to gauge perturbations depends on the choice of gauge and a background metric, but it does not depend on a particular form of a 3+1 system if its constrained solutions are equivalent to those of the Einstein equations. Stability of a number of known gauges is investigated in the limit of short-wavelength perturbations. All fixed gauges except a synchronous gauge are found to be ill posed. A maximal slicing gauge and its parabolic extension are shown to be ill posed as well. A necessary condition is derived for well-posedness of metric-dependent algebraic gauges. Well-posed metric-dependent gauges are found, however, to be generally unstable. Both instability and ill-posedness are associated with the existence of growing modes of coordinate perturbations related to perturbations of physical accelerations of reference frames
Solitons and action propagation according to general relativity (Part one)
International Nuclear Information System (INIS)
Stavroulakis, N.
1988-01-01
The current exposition of General Relativity involves two contradictory statements: at first it is asserted that every change in the distribution of matter brings about gravitational waves. Then it is asserted that, specifically, no gravitational effect is produced by the pulsations of a spherical source. By analysing the second statement, we conclude that it arises from a vicious circle tied up with mathematical errors which led to the Schwarzschild solution and the theory of black holes. In order to obtain the correct formulation of the problem, we establish rigorously the general form of the θ(4)-invariant space-time metrics on R x R 3 and bring out the principles allowing to associate gravitational effects with oscillating masses [fr
A database for extract solutions in general relativity
International Nuclear Information System (INIS)
Horvath, I.; Horvath, Zs.; Lukacs, B.
1993-07-01
The field of equations of General Relativity are coupled second order partial differential equations. Therefore no general method is known to generate solutions for prescribed initial and boundary conditions. In addition, the meaning of the particular coordinates cannot be known until the metric is not found. Therefore the result must permit arbitrary coordinate transformations, i.e. most kinds of approximating methods are improper. So exact solutions are necessary and each one is an individual product. For storage, retrieval and comparison database handling techniques are needed. A database of 1359 articles is shown (cross-referred at least once) published in 156 more important journals. It can be handled by dBase III plus on IBM PC's. (author) 5 refs.; 5 tabs
Charged point particles with magnetic moment in general relativity
International Nuclear Information System (INIS)
Amorim, R.; Tiomno, J.
1978-01-01
Halbwachs Lagrangean formalism for the theory of charged point particles with spin (g = 2) is generalized and formulated in General Relativity for particles of arbitrary charge and magnetic moment. Equations are obtained, both corresponding to Frenkel's condition S sub(μν) x sup(ν)=0 and to Nakano's condition S sub(μν) P sup(ν)=0. With the later condition the exact equations are highly coupled and non linear. When linearized in the electromagnetic and gravitational fields they coincide with de Groot-Suttorp equations for vanishing gravitational field and with Dixon-Wald equations in the absence of electromagnetic field. The equations corresponding to Frenkel's condition, when linearized in S sub(μν), coincide with Papapetrou's and Frenkel's equations in the corresponding limits [pt
The revival of General Relativity at Princeton: Daring Conservatism
Brill, Dieter; Blum, Alexander
2018-01-01
After General Relativity was established in essentially its present form in 1915 it was celebrated as a great success of mathematical physics. But the initial hopes for this theory as a basis for all of physics began to fade in the next several decades, as General Relativity was relegated to the margins of theoretical physics. Its fate began to rise in the 1950's in a revival of interest and research that over time made gravitational physics one of the hottest research topics it is today. One center of this renaissance was Princeton, where two relative newcomers explored new and different approaches to gravitational physics. Robert Dicke showed that gravity is not as inaccessible to experiment as was thought, and John Wheeler propelled it into the mainstream by proposing highly original and imaginative consequences of Einstein's theory. We will concentrate on these ideas that, in his characteristically intriguing style, Wheeler called "Daring Conservatism" - a term well known to his associates, but one he never mentioned in print. With the aid of unpublished manuscripts and notes we will explore Daring Conservatism's origin and motivation, its successes and failures, and the legacy it left behind.
The revival of General Relativity at Princeton: Daring Conservatism
Directory of Open Access Journals (Sweden)
Brill Dieter
2018-01-01
Full Text Available After General Relativity was established in essentially its present form in 1915 it was celebrated as a great success of mathematical physics. But the initial hopes for this theory as a basis for all of physics began to fade in the next several decades, as General Relativity was relegated to the margins of theoretical physics. Its fate began to rise in the 1950's in a revival of interest and research that over time made gravitational physics one of the hottest research topics it is today. One center of this renaissance was Princeton, where two relative newcomers explored new and different approaches to gravitational physics. Robert Dicke showed that gravity is not as inaccessible to experiment as was thought, and John Wheeler propelled it into the mainstream by proposing highly original and imaginative consequences of Einstein's theory. We will concentrate on these ideas that, in his characteristically intriguing style, Wheeler called "Daring Conservatism" -- a term well known to his associates, but one he never mentioned in print. With the aid of unpublished manuscripts and notes we will explore Daring Conservatism's origin and motivation, its successes and failures, and the legacy it left behind.
Further summation formulae related to generalized harmonic numbers
Zheng, De-Yin
2007-11-01
By employing the univariate series expansion of classical hypergeometric series formulae, Shen [L.-C. Shen, Remarks on some integrals and series involving the Stirling numbers and [zeta](n), Trans. Amer. Math. Soc. 347 (1995) 1391-1399] and Choi and Srivastava [J. Choi, H.M. Srivastava, Certain classes of infinite series, Monatsh. Math. 127 (1999) 15-25; J. Choi, H.M. Srivastava, Explicit evaluation of Euler and related sums, Ramanujan J. 10 (2005) 51-70] investigated the evaluation of infinite series related to generalized harmonic numbers. More summation formulae have systematically been derived by Chu [W. Chu, Hypergeometric series and the Riemann Zeta function, Acta Arith. 82 (1997) 103-118], who developed fully this approach to the multivariate case. The present paper will explore the hypergeometric series method further and establish numerous summation formulae expressing infinite series related to generalized harmonic numbers in terms of the Riemann Zeta function [zeta](m) with m=5,6,7, including several known ones as examples.
A superconducting gyroscope to test Einstein's general theory of relativity
Everitt, C. W. F.
1978-01-01
Schiff (1960) proposed a new test of general relativity based on measuring the precessions of the spin axes of gyroscopes in earth orbit. Since 1963 a Stanford research team has been developing an experiment to measure the two effects calculated by Schiff. The gyroscope consists of a uniform sphere of fused quartz 38 mm in diameter, coated with superconductor, electrically suspended and spinning at about 170 Hz in vacuum. The paper describes the proposed flight apparatus and the current state of development of the gyroscope, including techniques for manufacturing and measuring the gyro rotor and housing, generating ultralow magnetic fields, and mechanizing the readout.
Quantising general relativity using QED theory, an overview and extension
Bell, Sarah B. M.
2004-01-01
We summarise and discuss some of our previous results, which show that Bohr's theory of the one-electron atom may be derived from the theory underpinning Quantum ElectroDynamics (QED) or vice versa, and that General Relativity may also be derived from QED theory in the classical limit, if we use Newtonian mechanics in the right frame and self-similar tesseral hierarchies. We circumvent Newton's arguments against Descartes' vortex theory to show that the inverse square law for a force combined...
Bitopological spaces theory, relations with generalized algebraic structures and applications
Dvalishvili, Badri
2005-01-01
This monograph is the first and an initial introduction to the theory of bitopological spaces and its applications. In particular, different families of subsets of bitopological spaces are introduced and various relations between two topologies are analyzed on one and the same set; the theory of dimension of bitopological spaces and the theory of Baire bitopological spaces are constructed, and various classes of mappings of bitopological spaces are studied. The previously known results as well the results obtained in this monograph are applied in analysis, potential theory, general topology, a
General Video Game Evaluation Using Relative Algorithm Performance Profiles
DEFF Research Database (Denmark)
Nielsen, Thorbjørn; Barros, Gabriella; Togelius, Julian
2015-01-01
In order to generate complete games through evolution we need generic and reliably evaluation functions for games. It has been suggested that game quality could be characterised through playing a game with different controllers and comparing their performance. This paper explores that idea through...... investigating the relative performance of different general game-playing algorithms. Seven game-playing algorithms was used to play several hand-designed, mutated and randomly generated VGDL game descriptions. Results discussed appear to support the conjecture that well-designed games have, in average, a higher...... performance difference between better and worse game-playing algorithms....
Kerr-Taub-NUT General Frame, Energy, and Momentum in Teleparallel Equivalent of General Relativity
Directory of Open Access Journals (Sweden)
Gamal G. L. Nashed
2012-01-01
Full Text Available A new exact solution describing a general stationary and axisymmetric object of the gravitational field in the framework of teleparallel equivalent of general relativity (TEGR is derived. The solution is characterized by three parameters “the gravitational mass M, the rotation a, and the NUT L.” The vierbein field is axially symmetric, and the associated metric gives the Kerr-Taub-NUT spacetime. Calculation of the total energy using two different methods, the gravitational energy momentum and the Riemannian connection 1-form Γα̃β, is carried out. It is shown that the two methods give the same results of energy and momentum. The value of energy is shown to depend on the mass M and the NUT parameter L. If L is vanishing, then the total energy reduced to the energy of Kerr black hole.
Poisson, Eric
2010-05-01
A few years ago, in my review of Sean Carroll's book in Classical and Quantum Gravity [1], I wrote that while the 1970s was the decade of Weinberg [2] and Misner, Thorne and Wheeler [3], and while the eighties was the decade of Schutz [4] and Wald [5], the 2000s was clearly the decade of Hartle [6] and Carroll [7]. In my opinion, these books continue to stand out in the surprisingly dense crowd of introductory textbooks on general relativity. At the dawn of this new decade I look forward to see what fresh pedagogical insights will be produced next, and who will be revealed as the winners of the 2010s. It is, of course, much too early to tell, but Schutz is back, and he will set the standard just as he did back in 1985. This is the long-awaited second edition of his `First Course', a short, accessible, and very successful introduction to general relativity. The changes from the first edition are modest: Schutz wisely refrained from bloating the text with new topics, and limited himself to updating his discussion of gravitational-wave sources and detectors, neutron-star and black-hole astrophysics, and suggestions for further reading. Most importantly, he completely rewrote the chapter on cosmology, a topic that has evolved enormously since the first edition. The book begins in chapter 1 with a beautiful review of special relativity that emphasizes spacetime geometry and stays away from an algebraic approach based on the Lorentz transformation, which appears only later in the chapter. This is followed up in chapters 2 and 3 with an introduction to vector and tensor analysis in flat spacetime. The point of view is modern (tensors are defined as linear mapping of vectors and one-forms into real numbers) but the presentation is very accessible and avoids an overload of mathematical fine print. In chapter 4 the book introduces the spacetime description of fluids; it is here that the energy-momentum tensor makes its first appearance. The move to curved spacetime is
Proceedings of the 13th meeting for tandem accelerators and related techniques
Energy Technology Data Exchange (ETDEWEB)
NONE
2001-02-01
The 13th Meeting for Tandem Accelerators and Related Techniques was held on June 8-9, 2000 at Mutsu, Aomori Prefecture, under the auspices of Marine Research Laboratory, Mutsu Establishment, the Japan Atomic Energy Research Institute. About 60 people participated in the meeting from 27 universities and organizations, many of which have a tandem accelerator or an electrostatic accelerator. The objectives of the meeting are to exchange information on tandem accelerates or electrostatic accelerators by making a presentation on related research and topics, and also to enhance mutual friendship of participants, resulting in the contribution to associated R and D. The meeting mainly consisted of presentations by participants and corresponding Q and A; the present situation on facilities of accelerator mass spectrometers (AMS), operations of and research on tandem accelerators or electrostatic accelerators, applications of AMS, related techniques and applications using accelerators, and so on. This report summarizes the contents of presentations made in the meeting. The 30 of the presented papers are indexed individually. (J.P.N.)
Theory of Nonlocal Point Transformations in General Relativity
Directory of Open Access Journals (Sweden)
Massimo Tessarotto
2016-01-01
Full Text Available A discussion of the functional setting customarily adopted in General Relativity (GR is proposed. This is based on the introduction of the notion of nonlocal point transformations (NLPTs. While allowing the extension of the traditional concept of GR-reference frame, NLPTs are important because they permit the explicit determination of the map between intrinsically different and generally curved space-times expressed in arbitrary coordinate systems. For this purpose in the paper the mathematical foundations of NLPT-theory are laid down and basic physical implications are considered. In particular, explicit applications of the theory are proposed, which concern (1 a solution to the so-called Einstein teleparallel problem in the framework of NLPT-theory; (2 the determination of the tensor transformation laws holding for the acceleration 4-tensor with respect to the group of NLPTs and the identification of NLPT-acceleration effects, namely, the relationship established via general NLPT between particle 4-acceleration tensors existing in different curved space-times; (3 the construction of the nonlocal transformation law connecting different diagonal metric tensors solution to the Einstein field equations; and (4 the diagonalization of nondiagonal metric tensors.
The problem of time quantum mechanics versus general relativity
Anderson, Edward
2017-01-01
This book is a treatise on time and on background independence in physics. It first considers how time is conceived of in each accepted paradigm of physics: Newtonian, special relativity, quantum mechanics (QM) and general relativity (GR). Substantial differences are moreover uncovered between what is meant by time in QM and in GR. These differences jointly source the Problem of Time: Nine interlinked facets which arise upon attempting concurrent treatment of the QM and GR paradigms, as is required in particular for a background independent theory of quantum gravity. A sizeable proportion of current quantum gravity programs - e.g. geometrodynamical and loop quantum gravity approaches to quantum GR, quantum cosmology, supergravity and M-theory - are background independent in this sense. This book's foundational topic is thus furthermore of practical relevance in the ongoing development of quantum gravity programs. This book shows moreover that eight of the nine facets of the Problem of Time already occur upon ...
Correlated quadratures of resonance fluorescence and the generalized uncertainty relation
Arnoldus, Henk F.; George, Thomas F.; Gross, Rolf W. F.
1994-01-01
Resonance fluorescence from a two-state atom has been predicted to exhibit quadrature squeezing below the Heisenberg uncertainty limit, provided that the optical parameters (Rabi frequency, detuning, laser linewidth, etc.) are chosen carefully. When the correlation between two quadratures of the radiation field does not vanish, however, the Heisenberg limit for quantum fluctuations might be an unrealistic lower bound. A generalized uncertainty relation, due to Schroedinger, takes into account the possible correlation between the quadrature components of the radiation, and it suggests a modified definition of squeezing. We show that the coherence between the two levels of a laser-driven atom is responsible for the correlation between the quadrature components of the emitted fluorescence, and that the Schrodinger uncertainty limit increases monotonically with the coherence. On the other hand, the fluctuations in the quadrature field diminish with an increasing coherence, and can disappear completely when the coherence reaches 1/2, provided that certain phase relations hold.
Minimum size of charged particles in general relativity
International Nuclear Information System (INIS)
Sardelis, D.A.
1975-01-01
Spherical charged matter distributions are examined in a coordinate-free manner within the framework of general relativity. Irrespective of models chosen to describe the interior structure of a charged particle, it is found that the latter's total gravitational mass is positive definite, being finite only when there exists a lower bound for its invariant extension. For a simple choice of matter and charge distributions it is then shown that there is a minimum invarient size for the particle, below which no solution of the field equation exists, the matter density becoming negative and the space-tome devloping an intrinsic singularity in the exterior of the particle for radii less than this minimum. A mass renormalization is derived, valid at the moment of time symmetry, which relates the particle's total mass to its charge, bare mass and invariant extension. (author)
Quantum theory and Einstein's general relativity
Energy Technology Data Exchange (ETDEWEB)
v. Borzeszkowski, H.; Treder, H.
1982-11-01
We dicusss the meaning and prove the accordance of general relativity, wave mechanics, and the quantization of Einstein's gravitation equations themselves. Firstly, we have the problem of the influence of gravitational fields on the de Broglie waves, which influence is in accordance with Einstein's weak principle of equivalence and the limitation of measurements given by Heisenberg's uncertainty relations. Secondly, the quantization of the gravitational fields is a ''quantization of geometry.'' However, classical and quantum gravitation have the same physical meaning according to limitations of measurements given by Einstein's strong principle of equivalence and the Heisenberg uncertainties for the mechanics of test bodies.
Einstein and Beyond: A Critical Perspective on General Relativity
Directory of Open Access Journals (Sweden)
Ram Gopal Vishwakarma
2016-05-01
Full Text Available An alternative approach to Einstein’s theory of General Relativity (GR is reviewed, which is motivated by a range of serious theoretical issues inflicting the theory, such as the cosmological constant problem, presence of non-Machian solutions, problems related with the energy-stress tensor T i k and unphysical solutions. The new approach emanates from a critical analysis of these problems, providing a novel insight that the matter fields, together with the ensuing gravitational field, are already present inherently in the spacetime without taking recourse to T i k . Supported by lots of evidence, the new insight revolutionizes our views on the representation of the source of gravitation and establishes the spacetime itself as the source, which becomes crucial for understanding the unresolved issues in a unified manner. This leads to a new paradigm in GR by establishing equation R i k = 0 as the field equation of gravitation plus inertia in the very presence of matter.
Geometrical determination of the constant of motion in General Relativity
International Nuclear Information System (INIS)
Catoni, F.; Cannata, R.; Zampetti, P.
2009-01-01
In recent time a theorem, due to E. Beltrami, through which the integration of the geodesic equations of a curved manifold is obtained by means of a merely geometric method, has been revisited. This way of dealing with the problem is well in accordance with the geometric spirit of the Theory of General Relativity. In this paper we show another relevant consequence of this method. Actually, the constants of the motion, introduced in this geometrical way that is completely independent of Newton theory, are related to the conservation laws for test particles in the Einstein theory. These conservation laws may be compared with the conservation laws of Newton. In particular, by the conservation of energy (E) and the L z component of angular momentum, the equivalence of the conservation laws for the Schwarzschild field is verified and the difference between Newton and Einstein theories for the rotating bodies (Kerr metric) is obtained in a straightforward way.
New Probe of Departures from General Relativity Using Minkowski Functionals.
Fang, Wenjuan; Li, Baojiu; Zhao, Gong-Bo
2017-05-05
The morphological properties of the large scale structure of the Universe can be fully described by four Minkowski functionals (MFs), which provide important complementary information to other statistical observables such as the widely used 2-point statistics in configuration and Fourier spaces. In this work, for the first time, we present the differences in the morphology of the large scale structure caused by modifications to general relativity (to address the cosmic acceleration problem), by measuring the MFs from N-body simulations of modified gravity and general relativity. We find strong statistical power when using the MFs to constrain modified theories of gravity: with a galaxy survey that has survey volume ∼0.125(h^{-1} Gpc)^{3} and galaxy number density ∼1/(h^{-1} Mpc)^{3}, the two normal-branch Dvali-Gabadadze-Porrati models and the F5 f(R) model that we simulated can be discriminated from the ΛCDM model at a significance level ≳5σ with an individual MF measurement. Therefore, the MF of the large scale structure is potentially a powerful probe of gravity, and its application to real data deserves active exploration.
Apostolopoulos, P.; Bona, C.; Carot, J.; Mas, Ll; Sintes, A. M.; Stela, J.
2007-06-01
three-year dataset of the Microwave Anisotropy Probe. When these results are cross-referenced with other observations, such as supernova expansion surveys, we get fits for the cosmological parameters giving values with error bars that we can trust up to the third digit. This means that we have entered an era of precision cosmology. So things are getting really serious. Another exciting initiative started in summer 2005 with the debate about the role of general relativity in explaining the rotation speed profiles in galaxies. This was an old astrophysical problem, which was currently dealt with Newtonian gravity and an ad hoc amount of dark matter. Now it seems clear that general relativity has something to contribute, by lowering at least the amount of dark matter required to explain the observed rotation curves. So we have moved on substantially from the old times, the `dark years', when relativity was regarded even by well respected physicists as a sort of mathematical curiosity, a field with little experimental contrast, and therefore open to wild speculation. But maybe those `dark years' were not such a bad thing after all: there is a lot of fun in using advanced mathematics and unconstrained imagination. We can still find this fun nowadays in the search for explanation for dark matter and dark energy, and, of course, in the wonderful brane worlds. So these are exciting times for relativity, in many different ways. I hope that you will enjoy all of them in the proceedings. On behalf of the organizing committee, I would like to thank all the participants: without them this XXIXth edition of the ERE could not have taken place; special thanks to all those who contributed talks to the meeting, thus making possible the present proceedings. Let me finish by thanking the Sa Nostra foundation for offering its superb Conference Center and all the other sponsors, especially the Spanish Ministry of Education, and also the Balearic Islands Government, the SEGRE, ILIAS N6 and
Report to the Director General on the twenty third series of SAGSI meetings, 11-15 May 1987
International Nuclear Information System (INIS)
1987-08-01
This report (on the twenty third series of meetings of SAGSI - Standing Advisory Group on Safeguards Implementation) deals with the following items (of the agenda): Discussion on measurement uncertainties; Issues relating to safeguarding OLR facilities; Consideration of 90(a) and 90(b) statements (by the IAEA to Member States on the results of inspections); Considerations of the long-term criteria; The agenda for the next SAGSI meeting. The following annexes are included: SAGSI Response to DDG(SG) Question Regarding the Role of C/S; SAGSI Advice on Safeguarding On-load Refuelled Power Reactors; Draft: 90(b) Statement. 2 tabs
Farren, G. L.; Zhang, T.; Martin, S. B.; Thomas, K. T.
2017-01-01
Objective: To examine the relations of sex, exercise self-efficacy, outcome expectations, and social support with meeting physical activity guidelines (PAGs). Participants: Three hundred ninety-six college students participated in this study in the summer 2013. Methods: Students completed online questionnaires that assessed physical activity…
Einstein's general theory of relativity with modern applications in cosmology
Grøn, Øyvind
2007-01-01
Many of us have experienced the same; fallen and broken something. Yet supposedly, gravity is the weakest of the fundamental forces; it is claimed to be 10-15 times weaker than electromagnetism. Still, every one of us has more or less had a personal relationship with gravity. Einstein’s General Theory of Relativity: With Modern Applications in Cosmology by Oyvind Gron and Sigbjorn Hervik is about gravity and the concept of gravity as Albert Einstein saw it- curved spaces, four-dimensional manifolds and geodesics. The book starts with the 1st principals of relativity and an introduction to Einstein’s field equations. Next up are the three classical tests of the relativity theory and an introduction to black holes. The book contains several topics not found in other textbooks, such as Kaluza-Klein theory, anisotropic models of the universe, and new developments involving brane cosmology. Gron and Hervik have included a part in the book called "Advanced Topics." These topics range from the very edge of resea...
The Future of General Surgery: Evolving to Meet a Changing Practice.
Webber, Eric M; Ronson, Ashley R; Gorman, Lisa J; Taber, Sarah A; Harris, Kenneth A
2016-01-01
Similar to other countries, the practice of General Surgery in Canada has undergone significant evolution over the past 30 years without major changes to the training model. There is growing concern that current General Surgery residency training does not provide the skills required to practice the breadth of General Surgery in all Canadian communities and practice settings. Led by a national Task Force on the Future of General Surgery, this project aimed to develop recommendations on the optimal configuration of General Surgery training in Canada. A series of 4 evidence-based sub-studies and a national survey were launched to inform these recommendations. Generalized findings from the multiple methods of the project speak to the complexity of the current practice of General Surgery: (1) General surgeons have very different practice patterns depending on the location of practice; (2) General Surgery training offers strong preparation for overall clinical competence; (3) Subspecialized training is a new reality for today's general surgeons; and (4) Generation of the report and recommendations for the future of General Surgery. A total of 4 key recommendations were developed to optimize General Surgery for the 21st century. This project demonstrated that a high variability of practice dependent on location contrasts with the principles of implementing the same objectives of training for all General Surgery graduates. The overall results of the project have prompted the Royal College to review the training requirements and consider a more "fit for purpose" training scheme, thus ensuring that General Surgery residency training programs would optimally prepare residents for a broad range of practice settings and locations across Canada. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Accelerating particles in general relativity (stationary C-metric)
International Nuclear Information System (INIS)
Farhoosh, H.
1979-01-01
The purpose of this thesis is to study the physical and geometrical properties of uniformly accelerating particles in the general theory of relativity and it consists of four main parts. In the first part the structure of the Killing horizons in the static vacuum C-metric which represents the gravitational field of a uniformly accelerating Schwarzschild like particle (non-rotating and spherically symmetric) is studied. In the second part these results are generalized to include the effects of the rotation of the source. For small acceleration and small rotation this solution reveals the existance of three Killing horizons. Two the these horizons are the Schwarzschild and the Rindler surfaces which are mainly due to the mass and the acceleration of the particle, respectively. In part three the radial geodesic and non-geodesic motions in the static vacuum C-metric (non-rotating case) are investigated. The effect of the dragging of the inertial frame is also shown in this part. In part four the radiative behavior of the stationary charged C-metric representing the electro-gravitational field of a uniformly accelerating and rotating charged particle with magnetic monopole and the NUT-parameter are investigated. The physical quantities - the news function, mass loss, mass, charge and the multipole moments - are calculated. It is also shown in this part that the magnetic monopole in the presence of rotation and acceleration affects the electric charge
Outer boundary as arrested history in general relativity
Lau, S
2002-01-01
We present explicit outer boundary conditions for the canonical variables of general relativity. The conditions are associated with the causal evolution of a finite Cauchy domain, a so-called quasilocal boost, and they suggest a consistent scheme for modelling such an evolution numerically. The scheme involves a continuous boost in the spacetime orthogonal complement 'orthogonal' T sub p (B) of the tangent space T sub p (B) belonging to each point p on the system boundary B. We show how the boost rate may be computed numerically via equations similar to those appearing in canonical investigations of black-hole thermodynamics (although here holding at an outer two-surface rather than the bifurcate two-surface of a Killing horizon). We demonstrate the numerical scheme on a model example, the quasilocal boost of a spherical three-ball in Minkowski spacetime. Developing our general formalism with recent hyperbolic formulations of the Einstein equations in mind, we use Anderson and York's 'Einstein-Christoffel' hy...
Determinants related to gender differences in general practice utilization
DEFF Research Database (Denmark)
Jørgensen, Jeanette Therming; Andersen, John Sahl; Tjønneland, Anne
2016-01-01
OBJECTIVE: This study aims to describe the determinants related to gender differences in the GP utilization in Danish population aged 50-65 years. DESIGN: Cohort-based cross-sectional study. SETTING: Danish general practice. SUBJECTS: Totally, 54,849 participants of the Danish Diet, Cancer...... and post-menopausal HT. In a fully adjusted model, subjects with hypertension (1.63; 1.59-1.67), mental illness (1.63; 1.61-1.66), diabetes (1.56; 1.47-1.65), angina pectoris (1.28; 1.21-1.34), and unemployed persons (1.19; 1.18-1.21) had highest rates of GP visits. CONCLUSIONS: Gravidity and HT use...
Commutative deformations of general relativity: nonlocality, causality, and dark matter
Energy Technology Data Exchange (ETDEWEB)
De Vegvar, P.G.N. [SWK Research, Bellingham, WA (United States)
2017-01-15
Hopf algebra methods are applied to study Drinfeld twists of (3+1)-diffeomorphisms and deformed general relativity on commutative manifolds. A classical nonlocality length scale is produced above which microcausality emerges. Matter fields are utilized to generate self-consistent Abelian Drinfeld twists in a background independent manner and their continuous and discrete symmetries are examined. There is negligible experimental effect on the standard model of particles. While baryonic twist producing matter would begin to behave acausally for rest masses above ∝1-10 TeV, other possibilities are viable dark matter candidates or a right-handed neutrino. First order deformed Maxwell equations are derived and yield immeasurably small cosmological dispersion and produce a propagation horizon only for photons at or above Planck energies. This model incorporates dark matter without any appeal to extra dimensions, supersymmetry, strings, grand unified theories, mirror worlds, or modifications of Newtonian dynamics. (orig.)
General Relativity and Cosmology: Unsolved Questions and Future Directions
Directory of Open Access Journals (Sweden)
Ivan Debono
2016-09-01
Full Text Available For the last 100 years, General Relativity (GR has taken over the gravitational theory mantle held by Newtonian Gravity for the previous 200 years. This article reviews the status of GR in terms of its self-consistency, completeness, and the evidence provided by observations, which have allowed GR to remain the champion of gravitational theories against several other classes of competing theories. We pay particular attention to the role of GR and gravity in cosmology, one of the areas in which one gravity dominates and new phenomena and effects challenge the orthodoxy. We also review other areas where there are likely conflicts pointing to the need to replace or revise GR to represent correctly observations and consistent theoretical framework. Observations have long been key both to the theoretical liveliness and viability of GR. We conclude with a discussion of the likely developments over the next 100 years.
A geometric construction of the symplectic form in general relativity
International Nuclear Information System (INIS)
Szczyrba, W.
1977-01-01
The concept of the canonical quantization plays an important role in passing from classical to quantum systems. This procedure, well known in mechanics is based on the Hamilton (canonical) formulation of physical systems with finite degrees of freedom. In recent years an elegant geometric approach to the Hamilton formalism has been found. In this formulation a 2n-dimensional manifold Psub(2n) - the phase space of the system and a closed non-degenerate differential 2-form Ω on Psub(2n). The form Ω defines a Lie algebra structure in the set F of all smooth functions on Psub(2n). In this paper the multisymplectic structure for General Relativity is constructed. (Auth.)
Numerical performance of the parabolized ADM formulation of general relativity
International Nuclear Information System (INIS)
Paschalidis, Vasileios; Hansen, Jakob; Khokhlov, Alexei
2008-01-01
In a recent paper [Vasileios Paschalidis, Phys. Rev. D 78, 024002 (2008).], the first coauthor presented a new parabolic extension (PADM) of the standard 3+1 Arnowitt, Deser, Misner (ADM) formulation of the equations of general relativity. By parabolizing first-order ADM in a certain way, the PADM formulation turns it into a well-posed system which resembles the structure of mixed hyperbolic-second-order parabolic partial differential equations. The surface of constraints of PADM becomes a local attractor for all solutions and all possible well-posed gauge conditions. This paper describes a numerical implementation of PADM and studies its accuracy and stability in a series of standard numerical tests. Numerical properties of PADM are compared with those of standard ADM and its hyperbolic Kidder, Scheel, Teukolsky (KST) extension. The PADM scheme is numerically stable, convergent, and second-order accurate. The new formulation has better control of the constraint-violating modes than ADM and KST.
Ambiguous tests of general relativity on cosmological scales
International Nuclear Information System (INIS)
Zuntz, Joe; Baker, Tessa; Ferreira, Pedro G.; Skordis, Constantinos
2012-01-01
There are a number of approaches to testing General Relativity (GR) on linear scales using parameterized frameworks for modifying cosmological perturbation theory. It is sometimes assumed that the details of any given parameterization are unimportant if one uses it as a diagnostic for deviations from GR. In this brief report we argue that this is not necessarily so. First we show that adopting alternative combinations of modifications to the field equations significantly changes the constraints that one obtains. In addition, we show that using a parameterization with insufficient freedom significantly tightens the apparent theoretical constraints. Fundamentally we argue that it is almost never appropriate to consider modifications to the perturbed Einstein equations as being constraints on the effective gravitational constant, for example, in the same sense that solar system constraints are. The only consistent modifications are either those that grant near-total freedom, as in decomposition methods, or ones which map directly to a particular part of theory space
Gravitational waves from orbiting binaries without general relativity
Hilborn, Robert C.
2018-03-01
Using analogies with electromagnetic radiation, we present a calculation of the properties of gravitational radiation emitted by orbiting binary objects. The calculation produces results that have the same dependence on the masses of the orbiting objects, the orbital frequency, and the mass separation as do the results from the linear version of general relativity (GR). However, the calculation yields polarization, angular distributions, and overall power results that differ from those of GR. Nevertheless, the calculation produces waveforms that are very similar to those observed by the Laser Interferometer Gravitational-Wave Observatory (LIGO-VIRGO) gravitational wave collaboration in 2015 up to the point at which the binary merger occurs. The details of the calculation should be understandable by upper-level physics students and physicists who are not experts in GR.
One thing that general relativity says about photons in matter
International Nuclear Information System (INIS)
Antoci, S.; Mihich, L.
2001-01-01
For a moment it should be considered the strict epistemological standpoint of quantum field theory, that eventually comes to declare nonsensical any question about the photon posed outside the quantum-theoretical framework. One can avail of the works by Whittaker et al., and by Synge about the particle and the wave model of the photon in the vacuum of general relativity. It can also rely on important results found by Gordon and by Pham Mau Quan: thanks to Gordon's discovery of an effective metric these authors have been able to reduce to the vacuum case several problems of the electromagnetic theory of dielectrics. The joint use of these old findings allows one to conclude that a quantum-theoretical photon in a isotropic dielectric has a classical simile only if the dielectric is also homogeneous
Motivations for anti-gravity in general relativity
International Nuclear Information System (INIS)
Chardin, G.
1996-05-01
Arguments are presented showing that it is natural to interpret the negative mass part of the Kerr solution as representing the geometry experienced by antimatter. The C, P and T discrete transformations are considered for this geometry. The C and T properties of the proposed identification are found to be in agreement with the usual representation of antimatter. In addition, a property of perfect stigmatism through Kerr wormholes which allows general relativity to mimic anti-gravity is conjectured. Kerr wormholes would then act as 'super-mirrors' reversing the C, P and T images of an object seen through it. This interpretation is subjected to several experimental tests and able to provide an explanation, without any free parameter, of the 'CP'-violation observed in the neutral kaon system. (K.A.)
Probing strong-field general relativity near black holes
CERN. Geneva; Alvarez-Gaumé, Luís
2005-01-01
Nature has sprinkled black holes of various sizes throughout the universe, from stellar mass black holes in X-ray sources to supermassive black holes of billions of solar masses in quasars. Astronomers today are probing the spacetime near black holes using X-rays, and gravitational waves will open a different view in the near future. These tools give us an unprecedented opportunity to test ultra-strong-field general relativity, including the fundamental theorem of the uniqueness of the Kerr metric and Roger Penrose's cosmic censorship conjecture. Already, fascinating studies of spectral lines are showing the extreme gravitational lensing effects near black holes and allowing crude measurements of black hole spin. When the ESA-NASA gravitational wave detector LISA begins its observations in about 10 years, it will make measurements of dynamical spacetimes near black holes with an accuracy greater even than that which theoreticians can reach with their computations today. Most importantly, when gravitational wa...
International Nuclear Information System (INIS)
2013-01-01
In recent years, engineering oriented work, rather than basic research and development (R&D), has led to significant progress in improving the economics of innovative fast reactors and associated fuel cycle facilities, while maintaining and even enhancing the safety features of these systems. Optimization of plant size and layout, more compact designs, reduction of the amount of plant materials and the building volumes, higher operating temperatures to attain higher generating efficiencies, improvement of load factor, extended core lifetimes, high fuel burnup, etc. are good examples of achievements to date that have improved the economics of fast neutron systems. The IAEA, through its Technical Working Group on Fast Reactors (TWG-FR) and Technical Working Group on Nuclear Fuel Cycle Options and Spent Fuel Management (TWG-NFCO), devotes many of its initiatives to encouraging technical cooperation and promoting common research and technology development projects among Member States with fast reactor and advanced fuel cycle development programmes, with the general aim of catalysing and accelerating technology advances in these fields. In particular the theme of fast reactor deployment, scenarios and economics has been largely debated during the recent IAEA International Conference on Fast Reactors and Related Fuel Cycles: Safe Technologies and Sustainable Scenarios, held in Paris in March 2013. Several papers presented at this conference discussed the economics of fast reactors from different national and regional perspectives, including business cases, investment scenarios, funding mechanisms and design options that offer significant capital and energy production cost reductions. This Technical Meeting on Fast Reactors and Related Fuel Cycle Facilities with Improved Economic Characteristics addresses Member States’ expressed need for information exchange in the field, with the aim of identifying the main open issues and launching possible initiatives to help and
The generalized scheme-independent Crewther relation in QCD
Directory of Open Access Journals (Sweden)
Jian-Ming Shen
2017-07-01
Full Text Available The Principle of Maximal Conformality (PMC provides a systematic way to set the renormalization scales order-by-order for any perturbative QCD calculable processes. The resulting predictions are independent of the choice of renormalization scheme, a requirement of renormalization group invariance. The Crewther relation, which was originally derived as a consequence of conformally invariant field theory, provides a remarkable connection between two observables when the β function vanishes: one can show that the product of the Bjorken sum rule for spin-dependent deep inelastic lepton–nucleon scattering times the Adler function, defined from the cross section for electron–positron annihilation into hadrons, has no pQCD radiative corrections. The “Generalized Crewther Relation” relates these two observables for physical QCD with nonzero β function; specifically, it connects the non-singlet Adler function (Dns to the Bjorken sum rule coefficient for polarized deep-inelastic electron scattering (CBjp at leading twist. A scheme-dependent ΔCSB-term appears in the analysis in order to compensate for the conformal symmetry breaking (CSB terms from perturbative QCD. In conventional analyses, this normally leads to unphysical dependence in both the choice of the renormalization scheme and the choice of the initial scale at any finite order. However, by applying PMC scale-setting, we can fix the scales of the QCD coupling unambiguously at every order of pQCD. The result is that both Dns and the inverse coefficient CBjp−1 have identical pQCD coefficients, which also exactly match the coefficients of the corresponding conformal theory. Thus one obtains a new generalized Crewther relation for QCD which connects two effective charges, αˆd(Q=∑i≥1αˆg1i(Qi, at their respective physical scales. This identity is independent of the choice of the renormalization scheme at any finite order, and the dependence on the choice of the initial scale is
Genetics of generalized anxiety disorder and related traits.
Gottschalk, Michael G; Domschke, Katharina
2017-06-01
This review serves as a systematic guide to the genetics of generalized anxiety disorder (GAD) and further focuses on anxiety-relevant endophenotypes, such as pathological worry fear of uncertainty, and neuroticism. We inspect clinical genetic evidence for the familialityl heritability of GAD and cross-disorder phenotypes based on family and twin studies. Recent advances of linkage studies, genome-wide association studies, and candidate gene studies (eg, 5-HTT, 5-HT1A, MAOA, BDNF ) are outlined. Functional and structural neuroimaging and neurophysiological readouts relating to peripheral stress markers and psychophysiology are further integrated, building a multilevel disease framework. We explore etiologic factors in gene-environment interaction approaches investigating childhood trauma, environmental adversity, and stressful life events in relation to selected candidate genes ( 5-HTT, NPSR1, COMT, MAOA, CRHR1, RGS2 ), Additionally, the pharmacogenetics of selective serotonin reuptake inhibitor/serotonin-norepinephrine reuptake inhibitor treatment are summarized ( 5-HTT, 5-HT2A, COMT, CRHR1 ). Finally, GAD and trait anxiety research challenges and perspectives in the field of genetics, including epigenetics, are discussed.
What is a singular black hole beyond general relativity?
Bejarano, Cecilia; Olmo, Gonzalo J.; Rubiera-Garcia, Diego
2017-03-01
Exploring the characterization of singular black hole spacetimes, we study the relation between energy density, curvature invariants, and geodesic completeness using a quadratic f (R ) gravity theory coupled to an anisotropic fluid. Working in a metric-affine approach, our models and solutions represent minimal extensions of general relativity (GR) in the sense that they rapidly recover the usual Reissner-Nordström solution from near the inner horizon outwards. The anisotropic fluid helps modify only the innermost geometry. Depending on the values and signs of two parameters on the gravitational and matter sectors, a breakdown of the correlations between the finiteness/divergence of the energy density, the behavior of curvature invariants, and the (in)completeness of geodesics is obtained. We find a variety of configurations with and without wormholes, a case with a de Sitter interior, solutions that mimic nonlinear models of electrodynamics coupled to GR, and configurations with up to four horizons. Our results raise questions regarding what infinities, if any, a quantum version of these theories should regularize.
Origins and development of the Cauchy problem in general relativity
Ringström, Hans
2015-06-01
The seminal work of Yvonne Choquet-Bruhat published in 1952 demonstrates that it is possible to formulate Einstein's equations as an initial value problem. The purpose of this article is to describe the background to and impact of this achievement, as well as the result itself. In some respects, the idea of viewing the field equations of general relativity as a system of evolution equations goes back to Einstein himself; in an argument justifying that gravitational waves propagate at the speed of light, Einstein used a special choice of coordinates to derive a system of wave equations for the linear perturbations on a Minkowski background. Over the following decades, Hilbert, de Donder, Lanczos, Darmois and many others worked to put Einstein's ideas on a more solid footing. In fact, the issue of local uniqueness (giving a rigorous justification for the statement that the speed of propagation of the gravitational field is bounded by that of light) was already settled in the 1930s by the work of Stellmacher. However, the first person to demonstrate both local existence and uniqueness in a setting in which the notion of finite speed of propagation makes sense was Yvonne Choquet-Bruhat. In this sense, her work lays the foundation for the formulation of Einstein's equations as an initial value problem. Following a description of the results of Choquet-Bruhat, we discuss the development of three research topics that have their origin in her work. The first one is local existence. One reason for addressing it is that it is at the heart of the original paper. Moreover, it is still an active and important research field, connected to the problem of characterizing the asymptotic behaviour of solutions that blow up in finite time. As a second topic, we turn to the questions of global uniqueness and strong cosmic censorship. These questions are of fundamental importance to anyone interested in justifying that the Cauchy problem makes sense globally. They are also closely
On the relation of the theoretical foundations of quantum theory and general relativity theory
International Nuclear Information System (INIS)
Kober, Martin
2010-01-01
The specific content of the present thesis is presented in the following way. First the most important contents of quantum theory and general relativity theory are presented. In connection with the general relativity theory the mathematical property of the diffeomorphism invariance plays the deciding role, while concerning the quantum theory starting from the Copenhagen interpretation first the measurement problem is treated, before basing on the analysis of concrete phenomena and the mathematical apparatus of quantum theory the nonlocality is brought into focus as an important property. This means that both theories suggest a relationalistic view of the nature of the space. This analysis of the theoretical foundations of quantum theory and general relativity theory in relation to the nature of the space obtains only under inclusion of Kant's philosophy and his analysis of the terms space and time as fundamental forms of perception its full persuasive power. Then von Weizsaeckers quantum theory of the ur-alternatives is presented. Finally attempts are made to apply the obtained knowledge to the question of the quantum-theoretical formulation of general relativity theory.
77 FR 39264 - Meeting of the Attorney General's National Task Force on Children Exposed to Violence
2012-07-02
... Attorney General's National Task Force on Children Exposed to Violence AGENCY: Office of Justice Programs... Attorney General's National Task Force on Children Exposed to Violence (the ``task force''). The task force... areas of children exposed to violence for the purpose of addressing the epidemic levels of exposure to...
Spacetime and Geometry: An Introduction to General Relativity
International Nuclear Information System (INIS)
Poisson, E
2005-01-01
The ever growing relevance of general relativity to astrophysics and cosmology continues to motivate the publication of new textbooks which put the theory in a fresh perspective informed by recent developments. While the 1970s were the decade of Weinberg and Misner et al and the 80s the decade of Schutz and Wald, this is clearly the decade of Hartle and Carroll. Hartle has introduced a novel pedagogical approach to teaching general relativity, which he convincingly argues should be done in the standard undergraduate physics curriculum. His 'physics-first approach' emphasizes physical phenomena and minimizes mathematical formalism. Hartle achieves a lot by introducing only the spacetime metric and the geodesic equation, which are the main tools needed to explore curved spacetime and extract physical consequences. To be sure, to explain how the metric is obtained in the first place does require a background of differential geometry and the formulation of the Einstein field equations. But in Hartle's book this material is wisely presented at a later stage, after an ample sampling of the physics of curved spacetime has motivated the need for the advanced mathematics. Carroll follows instead the traditional route, what Hartle calls the 'math-first approach', in which one introduces first the required mathematical formalism and only then derives the physical consequences. He is, of course, in good company, as this is the method followed in all existing textbooks (with Hartle's being the sole exception). Carroll's approach may not be original, but it is tried and true, and the result of Carroll's efforts is an excellent introduction to general relativity. The book covers the standard topics that would be found in virtually all textbooks (differential geometry, the field equations, linearized theory, black holes, and cosmology), but in addition it contains topics (such as quantum field theory in curved spacetime) which can rarely be found in introductory texts. All these
Abstracts of the Atlantic Geoscience Society's 2007 colloquium and annual general meeting
International Nuclear Information System (INIS)
Johnson, S.; Parkhill, M.; Wilson, R.; Desrosiers, M.; Lentz, D.; Pitre, C.; Pronk, T.; Spooner, I.; Toole, R.; Wallace, P.
2007-01-01
The Atlantic Geoscience Society (AGS) hosts annual meetings, workshops and field trips to promote a better understanding of the geology of Atlantic Canada. This colloquium highlighted current research in the Atlantic provinces with special sessions devoted to patterns and geohazards in the North Atlantic; late and post-glacial climate change events in eastern Canada; salt matters; tectonic, thermal and resource aspects of Paleozoic to Mesozoic evaporite basins; mineral resources research by students of the Society of Economic Geologists; dendrochronology; a physical volcanology workshop; and, a North American soil geochemical landscape project orientation session. One of the 74 papers presented at this colloquium has been catalogued separately for inclusion in this database
Bliss, Julie; While, Alison E
2014-01-01
General practitioners and district nurses have a long history of providing care outside the hospital setting. With health care increasingly moving out of the hospital setting, there are more opportunities for general practitioners and district nurses to work together to meet the health needs of the local population. However, the reduction in qualiﬁed specialist practitioner district nurses over the last decade is concerning. The need for an effective district nursing service has been recognised by the Department of Health in their own model - the nature of district nursing work, often over a long period, enables relationships to develop with the patient, family and informal carers as a basis for anticipatory care to manage long-term conditions. Communication and understanding of the role are central to enhance effective working between general practitioners and district nurses, which can be fostered by engagement in community-oriented integrated care and case management.
A Time Domain Waveform for Testing General Relativity
International Nuclear Information System (INIS)
Huwyler, Cédric; Jetzer, Philippe; Porter, Edward K
2015-01-01
Gravitational-wave parameter estimation is only as good as the theory the waveform generation models are based upon. It is therefore crucial to test General Relativity (GR) once data becomes available. Many previous works, such as studies connected with the ppE framework by Yunes and Pretorius, rely on the stationary phase approximation (SPA) to model deviations from GR in the frequency domain. As Fast Fourier Transform algorithms have become considerably faster and in order to circumvent possible problems with the SPA, we test GR with corrected time domain waveforms instead of SPA waveforms. Since a considerable amount of work has been done already in the field using SPA waveforms, we establish a connection between leading-order-corrected waveforms in time and frequency domain, concentrating on phase-only corrected terms. In a Markov Chain Monte Carlo study, whose results are preliminary and will only be available later, we will assess the ability of the eLISA detector to measure deviations from GR for signals coming from supermassive black hole inspirals using these corrected waveforms. (paper)
A New Solution for Einstein Field Equation in General Relativity
Mousavi, Sadegh
2006-05-01
There are different solutions for Einstein field equation in general relativity that they have been proposed by different people the most important solutions are Schwarzchild, Reissner Nordstrom, Kerr and Kerr Newmam. However, each one of these solutions limited to special case. I've found a new solution for Einstein field equation which is more complete than all previous ones and this solution contains the previous solutions as its special forms. In this talk I will present my new metric for Einstein field equation and the Christofel symbols and Richi and Rieman tensor components for the new metric that I have calculated them by GR TENSOR software. As a result I will determine the actual movement of black holes which is different From Kerr black hole's movement. Finally this new solution predicts, existence of a new and constant field in the nature (that nobody can found it up to now), so in this talk I will introduce this new field and even I will calculate the amount of this field. SADEGH MOUSAVI, Amirkabir University of Technology.
Preferred Spatial Directions in the Universe: a General Relativity Approach
Directory of Open Access Journals (Sweden)
Borissova L.
2006-10-01
Full Text Available Herein is constructed, using General Relativity, the space metric along the Earth’s trajectory in the Galaxy, where the Earth traces outs a complicated spiral in its orbital motion around the Sun and its concomitant motion with the solar system around the centre of the Galaxy. It is deduced herein that this space is inhomogeneous and anisotropic. The observable properties of the space, characterizing its gravitation, rotation, deformation, and curvature, are obtained. The theory predicts that the observable velocity of light is anisotropic, due to the anisotropy and inhomogeneity of space caused by the presence of gravitation and the space rotation, despite the world-invariance of the velocity of light remaining unchanged. It is calculated that two pairs of synchronised clocks should record a different speed of light for light beams travelling towards the Sun and orthogonal to this direction, of about 4×10−4 c (i. e. 120 km/sec, 0.04% of the measured velocity of light c. This effect should have oscillations with a 12-hour period (due to the daily rotation of the Earth and 6 month period (due to the motion of the Earth around the Sun. The best equipment for detecting the effect is that being used by R. T. Cahill (Flinders University, Australia in his current experiments measuring the velocity of light in an RF coaxial-cable equipped with a pair of high precision synchronized Rb atomic clocks.
Exact solutions of the Bach field equations of general relativity
Fiedler, B.; Schimming, R.
1980-02-01
Conformally invariant gravitational field equations on the hand and fourth order field equations on the other were discussed in the early history of general relativity (Weyl Einstein, Bach et al.) and have recently gained some new interest (Deser, P. Günther, Treder, et al.). The equations Bαβ=0 or Bαβ= ϰTαβ, where Bαβ denotes the Bach tensor and Tαβ a suitable energy-momentum tensor, possess both the mentioned properties. We construct exact solutions ds2= gαβdxαdxβ of the Bach equations: (2, 2)-decomposable, centrally symmetric and pp-wave solutions. The gravitational field gαβ is coupled by Bαβ= ϰTαβ to an electromagnetic field Fαβ=- Fαβ obeying the Maxwell equations or to a neutrino field ϕ A obeying the Weyl equations respectively. Among interesting new metrics ds2 there appear some physically well-known ones, such as the De Sitter universe, the Weyl-Trefftz metric. and the plane-fronted gravitational waves with parallel rays (pp-waves) known from Einstein's theory. The solutions are built up by means of special techniques: A separation method for (2, 2)-decomposable solutions, simplification of centrally symmetric metrics by a suitable conformal transformation, and complex function methods for pp-wave solutions.
General relativity cosmological models without the big bang
International Nuclear Information System (INIS)
Rosen, N.
1985-01-01
Attention is given to the so-called standard model of the universe in the framework of the general theory of relativity. This model is taken to be homogeneous and isotropic and filled with an ideal fluid characterized by a density and a pressure. Taking into consideration, however, the assumption that the universe began in a singular state, it is found hard to understand why the universe is so nearly homogeneous and isotropic at present for a singularity represents a breakdown of physical laws, and the initial singularity cannot, therefore, predetermine the subsequent symmetries of the universe. The present investigation has the objective to find a way of avoiding this initial singularity, i.e., to look for a cosmological model without the big bang. The idea is proposed that there exists a limiting density of matter of the order of magnitude of the Planck density, and that this was the density of matter at the moment at which the universe began to expand
Mixed hyperbolic-second-order-parabolic formulations of general relativity
International Nuclear Information System (INIS)
Paschalidis, Vasileios
2008-01-01
Two new formulations of general relativity are introduced. The first one is a parabolization of the Arnowitt-Deser-Misner formulation and is derived by the addition of combinations of the constraints and their derivatives to the right-hand side of the Arnowitt-Deser-Misner evolution equations. The desirable property of this modification is that it turns the surface of constraints into a local attractor because the constraint propagation equations become second-order parabolic independently of the gauge conditions employed. This system may be classified as mixed hyperbolic--second-order parabolic. The second formulation is a parabolization of the Kidder-Scheel-Teukolsky formulation and is a manifestly mixed strongly hyperbolic--second-order-parabolic set of equations, bearing thus resemblance to the compressible Navier-Stokes equations. As a first test, a stability analysis of flat space is carried out and it is shown that the first modification exponentially damps and smoothes all constraint-violating modes. These systems provide a new basis for constructing schemes for long-term and stable numerical integration of the Einstein field equations.
Radion stabilization by stringy effects in general relativity
International Nuclear Information System (INIS)
Patil, Subodh P.; Brandenberger, Robert
2005-01-01
We consider the effects of a gas of closed strings (treated quantum mechanically) on a background where one dimension is compactified on a circle. After we address the effects of a time-dependent background on aspects of the string spectrum that concern us, we derive the energy-momentum tensor for a string gas and investigate the resulting space-time dynamics. We show that a variety of trajectories are possible for the radius of the compactified dimension, depending on the nature of the string gas, including a demonstration within the context of general relativity (i.e. without a dilaton) of a solution where the radius of the extra dimension oscillates about the self-dual radius, without invoking matter that violates the various energy conditions. In particular, we find that in the case where the string gas is in thermal equilibrium, the radius of the compactified dimension dynamically stabilizes at the self-dual radius, after which a period of usual Friedmann-Robertson-Walker cosmology of the three uncompactified dimensions can set in. We show that our radion stabilization mechanism requires a stringy realization of inflation as scalar field driven inflation invalidates our mechanism. We also show that our stabilization mechanism is consistent with observational bounds
Cosmological applications of singular hypersurfaces in general relativity
Laguna-Castillo, Pablo
Three applications to cosmology of surface layers, based on Israel's formalism of singular hypersurfaces and thin shells in general relativity, are presented. Einstein's field equations are analyzed in the presence of a bubble nucleated in vacuum phase transitions within the context of the old inflationary universe scenario. The evolution of a bubble with vanishing surface energy density is studied. It is found that such bubbles lead to a worm-hole matching. Next, the observable four-dimensional universe is considered as a singular hypersurface of discontinuity embedded in a five-dimensional Kaluza-Klein cosmology. It is possible to rewrite the projected five-dimensional Einstein equations on the surface layer in a similar way to the four-dimensional Robertson-Walker cosmology equations. Next, a model is described for an infinite-length, straight U(1) cosmic string as a cylindrical, singular shell enclosing a region of false vacuum. A set of equations is introduced which are required to develop a three-dimensional computer code whose purpose is to study the process of intercommuting cosmic strings with the inclusion of gravitational effects. The outcome is evolution and constraint equations for the gravitational, scalar and gauge field of two initially separated, perpendicular, cosmic strings.
Gravitational field of massive point particle in general relativity
International Nuclear Information System (INIS)
Fiziev, P.P.
2003-10-01
Using various gauges of the radial coordinate we give a description of the static spherically symmetric space-times with point singularity at the center and vacuum outside the singularity. We show that in general relativity (GR) there exist infinitely many such solutions to the Einstein equations which are physically different and only some of them describe the gravitational field of a single massive point particle. In particular, we show that the widespread Hilbert's form of Schwarzschild solution does not solve the Einstein equations with a massive point particle's stress-energy tensor. Novel normal coordinates for the field and a new physical class of gauges are proposed, in this way achieving a correct description of a point mass source in GR. We also introduce a gravitational mass defect of a point particle and determine the dependence of the solutions on this mass defect. In addition we give invariant characteristics of the physically and geometrically different classes of spherically symmetric static space-times created by one point mass. (author)
Simulation of merging neutron stars in full general relativity
International Nuclear Information System (INIS)
Shibata, M.
2001-01-01
We have performed 3D numerical simulations for merger of equal mass binary neutron stars in full general relativity. We adopt a Γ-law equation of state in the form P = (Γ - 1)ρε where P, ρ, ε and Γ are the pressure, rest mass density, specific internal energy, and the adiabatic constant. As initial conditions, we adopt models of irrotational binary neutron stars in a quasiequilibrium state. Simulations have been carried out for a wide range of Γ and compactness of neutron stars, paying particular attention to the final product and gravitational waves. We find that the final product depends sensitively on the initial compactness of the neutron stars: In a merger between sufficiently compact neutron stars, a black hole is formed in a dynamical timescale. As the compactness is decreased, the formation timescale becomes longer and longer. It is also found that a differentially rotating massive neutron star is formed instead of a black hole for less compact binary cases. In the case of black hole formation, the disk mass around the black hole appears to be very small; less than 1% of the total rest mass. It is indicated that waveforms of high-frequency gravitational waves after merger depend strongly on the compactness of neutron stars before the merger. We point out importance of detecting such gravitational waves of high frequency to constrain the maximum allowed mass of neutron stars. (author)
Hydrodynamics in full general relativity with conservative adaptive mesh refinement
East, William E.; Pretorius, Frans; Stephens, Branson C.
2012-06-01
There is great interest in numerical relativity simulations involving matter due to the likelihood that binary compact objects involving neutron stars will be detected by gravitational wave observatories in the coming years, as well as to the possibility that binary compact object mergers could explain short-duration gamma-ray bursts. We present a code designed for simulations of hydrodynamics coupled to the Einstein field equations targeted toward such applications. This code has recently been used to study eccentric mergers of black hole-neutron star binaries. We evolve the fluid conservatively using high-resolution shock-capturing methods, while the field equations are solved in the generalized-harmonic formulation with finite differences. In order to resolve the various scales that may arise, we use adaptive mesh refinement (AMR) with grid hierarchies based on truncation error estimates. A noteworthy feature of this code is the implementation of the flux correction algorithm of Berger and Colella to ensure that the conservative nature of fluid advection is respected across AMR boundaries. We present various tests to compare the performance of different limiters and flux calculation methods, as well as to demonstrate the utility of AMR flux corrections.
Bose gas with generalized dispersion relation plus an energy gap
Solis, M. A.; Martinez, J. G.; Garcia, J.
We report the critical temperature, the condensed fraction, the internal energy and the specific heat for a d-dimensional Bose gas with a generalized dispersion relation plus an energy gap, i.e., ɛ =ɛ0 for k = 0 and ɛ =ɛ0 + Δ +csks , for k > 0 , where ℏk is the particle momentum, ɛ0 the lowest particle energy, cs a constant with dimension of energy multiplied by a length to the power s > 0 . When Δ > 0 , a Bose-Einstein critical temperature Tc ≠ 0 exists for any d / s >= 0 at which the internal energy shows a peak and the specific heat shows a jump. The critical temperature and the specific heat jump increase as functions of the gap but they decrease as functions of d / s . Thermodynamic properties are ɛ0 independent since this is just a reference energy. For Δ = 0 we recover the results reported in Ref. [1]. V. C. Aguilera-Navarro, M. de Llano y M. A. Solís, Eur. J. Phys. 20, 177 (1999). We acknowledge partial support from Grants PAPIIT IN111613 and CONACyT 221030.
Dynamics of spinning compact binaries in general relativity
Hartl, Michael David
This thesis investigates the dynamics of binary systems composed of spinning compact objects in the context of general relativity. Compact binaries are promising sources of gravitational radiation for both ground- and space-based gravitational-wave detectors. If the dynamics of these systems were chaotic, the number of waveform templates needed to match a given gravitational-wave signal would grow exponentially with increasing detection sensitivity, rendering the preferred matched filter detection method computationally impractical. It is therefore urgent to understand whether the binary dynamics can be chaotic, and, if so, how prevalent this chaos is. We first consider the dynamics of a spinning compact object orbiting a much more massive rotating black hole, as modeled by the Papapetrou equations in Kerr spacetime. We find that many initial conditions lead to positive Lyapunov exponents, indicating chaotic dynamics. Despite the formal existence of chaotic solutions, we find that chaos occurs only for physically unrealistic values of the small body's spin. As a result, chaos will not affect theoretical templates in the extreme mass-ratio limit for which the Papapetrou equations are valid. We next consider the dynamics of spinning black-hole binaries, as modeled by the post-Newtonian (PN) equations, which are valid for orbital velocities much smaller than the speed of light. We study thoroughly the special case of quasi-circular orbits with comparable mass ratios. Our survey shows that chaos occurs in a negligible fraction of possible configurations, and only for such small radii that the PN approximation is likely to be invalid. As a result, at least in the case of comparable mass black-hole binaries, theoretical templates will not be significantly affected by chaos. In a final, self-contained chapter, we discuss various methods for the calculation of Lyapunov exponents in systems of ordinary differential equations. We introduce several new techniques applicable
Tenth Negotiators' Standing Sub-Group (NSSG-10) and related meetings
International Nuclear Information System (INIS)
Drew, M.
2003-01-01
The Tenth Meeting of the ITER Negotiators' Standing Sub-Group (NSSG-10) and related meetings were held during the period 18-27 September 2003 at Culham, UK, at the kind invitation of UKAEA-Euratom, who placed their JET meeting facilities at the disposal of the Sub-Group and its Topical Working Groups. The European Union hosted the meeting, which was also attended by delegations from Canada, China, Japan, the Republic of Korea, the Russian Federation and the USA. The focussed discussion enabled further good progress to be made in developing the many different elements that will be involved in the joint implementation of ITER. In particular the discussions on procurement allocation reached the stage at which it was possible to charge the NSSG Moderator to transmit to the Participants at a high level an agreed proposed allocation among the Parties of responsibilities to procure and contribute in kind the various systems and components for ITER construction. The proposed allocation is well defined up to the current limits of understanding on cost sharing and includes areas of flexibility to allow a full matching to the definitive cost sharing as and when it is finally agreed
Probing General Relativity and New Physics with Lunar Laser Ranging
Energy Technology Data Exchange (ETDEWEB)
Dell' Agnello, S. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Maiello, M., E-mail: mauro.maiello@lnf.infn.it [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Currie, D.G. [University of Maryland (UMD), College Park, MD (United States); Boni, A.; Berardi, S.; Cantone, C.; Delle Monache, G.O.; Intaglietta, N.; Lops, C.; Garattini, M.; Martini, M.; Patrizi, G.; Porcelli, L.; Tibuzzi, M. [Laboratori Nazionali di Frascati (LNF) dell' INFN, Frascati, Rome (Italy); Vittori, R. [Aeronautica Militare Italiana (AMI), Rome (Italy); Agenzia Spaziale Italiana (ASI), Rome (Italy); Bianco, G. [ASI-Centro di Geodesia Spaziale, Matera (Italy); Coradini, A. [INAF-Istituto di Fisica dello Spazio Interplanetario (IFSI), Via Fosso del Cavaliere 100, 00133 Rome (Italy); Dionisio, C. [Rheinmetall Italia S.p.A., Via Affile 102, 00131 Rome (Italy); March, R. [INFN-LNF and CNR-Istituto per le Applicazioni del Calcolo (IAC), Viale del Policlinico 137, 00161 Rome (Italy); Bellettini, G. [INFN-LNF and Department of Mathematics, University of Rome ' Tor Vergata' , Via della Ricerca Scientifica, 00133 Rome (Italy); and others
2012-11-11
Over the past 40 years, Lunar Laser Ranging (LLR, developed by the Univ. of Maryland (PI) and INFN-LNF (Co-PI)) to the Apollo Cube Corner Retroreflector (CCR) arrays have supplied almost all the significant tests of General Relativity (Currie et al., 2009 [12]). LLR can evaluate the PPN (Post Newtonian Parameters), addressing this way both the possible changes in the gravitational constant and the self-energy properties of the gravitational field. In addition, the LLR has provided significant information on the composition and origin of the Moon. This is the only Apollo experiment that is still in operation. Initially the Apollo LLR arrays contributed a negligible fraction of the ranging error budget. Over the decades, the ranging capabilities of the ground stations have improved by more than two orders of magnitude. Now, because of the lunar librations, the existing Apollo retroreflector arrays contribute a significant fraction of the limiting errors in the range measurements. We built a new experimental apparatus (the 'Satellite/Lunar Laser Ranging Characterization Facility', SCF) and created a new test procedure (the SCF-Test) to characterize and model the detailed thermal behavior and the optical performance of cube corner laser retroreflectors in space for industrial and scientific applications (Dell'Agnello et al., 2011 [13]). Our key experimental innovation is the concurrent measurement and modeling of the optical Far Field Diffraction Pattern (FFDP) and the temperature distribution of the SLR retroreflector payload under thermal conditions produced with a close-match solar simulator. The apparatus includes infrared cameras for non-invasive thermometry, thermal control and real-time movement of the payload to experimentally simulate satellite orientation on orbit with respect to both solar illumination and laser interrogation beams. These unique capabilities provide experimental validation of the space segment for SLR and Lunar Laser Ranging
PLANCK, the Satellite: a New Experimental Test of General Relativity
Directory of Open Access Journals (Sweden)
Rabounski D.
2008-04-01
Full Text Available If the origin of a microwave background (EMB is the Earth, what would be its density and associated dipole anisotropy measured at different altitudes from the surface of the Earth? The mathematical methods of the General Theory of Relativity are applied herein to answer these questions. The density of the EMB is answered by means of Einstein's equations for the electromagnetic field of the Earth. The dipole anisotropy, which is due to the rapid motion of the source (the Earth in the weak intergalactic field, is analysed by using the geodesic equations for light-like particles (photons, which are mediators for electromagnetic radiation. It is shown that the EMB decreases with altitude so that the density of its energy at the altitude of the COBE orbit (900km is 0.68 times less than that at the altitude of a U2 aeroplane (25km. Furthermore, the density at the 2nd Lagrange point (1.5 million km, the position of the WMAP and PLANCK satellites should be only 10$^{-7}$ of the value detected by a U2 aeroplane or at the COBE orbit. The dipole anisotropy of the EMB doesn't depend on altitude from the surface of the Earth, it should be the same irrespective of the altitude at which measurements are taken. This result is in support to the experimental and observational analysis conducted by P.-M.Robitaille, according to which the 2.7K microwave background, first observed by Penzias and Wilson, is not of cosmic origin, but of the Earth, and is generated by the oceans. WMAP indicated the same anisotropy of the microwave background at the 2nd Lagrange point that near the Earth. Therefore when PLANCK, which is planned on July, 2008, will manifest the 2.7K monopole microwave signal deceased at the 2nd Langrange point, it will be a new experimental verification of Einstein's theory.
PLANCK, the Satellite: a New Experimental Test of General Relativity
Directory of Open Access Journals (Sweden)
Borissova L.
2008-04-01
Full Text Available If the origin of a microwave background (EMB is the Earth, what would be its density and associated dipole anisotropy measured at different altitudes from the surface of the Earth? The mathematical methods of the General Theory of Relativity are applied herein to answer these questions. The density of the EMB is answered by means of Einstein’s equations for the electromagnetic field of the Earth. The dipole anisotropy, which is due to the rapid motion of the source (the Earth in the weak intergalactic field, is analysed by using the geodesic equations for light-like particles (photons, which are mediators for electromagnetic radiation. It is shown that the EMB decreases with altitude so that the density of its energy at the altitude of the COBE orbit (900km is 0.68 times less than that at the altitude of a U2 aeroplane (25 km. Furthermore, the density at the 2nd Lagrange point (1.5 million km, the position of the WMAP and PLANCK satellites should be only 1E-7 of the value detected by a U2 aeroplane or at the COBE orbit. The dipole anisotropy of the EMB doesn’t depend on altitude from the surface of the Earth, it should be the same irrespective of the altitude at which measurements are taken. This result is in support to the experimental and observational analysis conducted by P.-M. Robitaille, according to which the 2.7 K microwave background, first observed by Penzias and Wilson, is not of cosmic origin, but of the Earth, and is generated by the oceans. WMAP indicated the same anisotropy of the microwave background at the 2nd Lagrange point that near the Earth. Therefore when PLANCK, which is planned on July, 2008, will manifest the 2.7 K monopole microwave signal deceased at the 2nd Langrange point, it will be a new experimental verification of Einstein’s theory.
Disseminating General Relativity for 21st century astronomy
Crosta, Mariateresa
2015-08-01
The talk aims to present two outreach projects - initially developed for the ESA Gaia satellite, a multidisciplinary mission launched on December 19, 2013 - available to the OAD community: NeST and "The Meaning of Light".NeST is an interactive educational tool, that displays how the theory of GR rules the Universe, it creates a performance physically "belonging" to the exhibition space and moving through it, materializing what J.A. Wheeler said "mass tells space-time how to curve, and space-time tells mass how to move"."The Meaning of Light" is a short motion comics, part of an extensive outreach program called "The History of Photons" whose main theme is the story of a beam of stellar photons that, after leaving the progenitor star, propagates through the Universe and, once intercepted come into contact with a team of scientists: here begins their adventure to be taken "back" home and in doing so the scientists, and the spectators, are driven to discover the wonders of which the light are the bearers.The description of the journey of the photons becomes, therefore, an opportunity to easily tell the fascinating topics of Astrophysics and General Relativity, i.e. the complexity and the infinite beauty of the Universe in which we live.For this movie a new theme song was produced, "Singing the Stars", whose refrain (Oh Be A Fine Girl / Guy Kiss Me Little Thing, Yeah) adds to the famous mnemonic for stellar classification (OBAFGKM) the new stellar types LTY discovered in recent years.
77 FR 5816 - National Institute of General Medical Sciences Notice of Closed Meeting
2012-02-06
..., Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and Developmental Biology Research; 93.88, Minority Access to Research Careers... HUMAN SERVICES National Institutes of Health National Institute of General Medical Sciences Notice of...
77 FR 9677 - National Institute of General Medical Sciences; Notice of Closed Meeting
2012-02-17
... HUMAN SERVICES National Institutes of Health National Institute of General Medical Sciences; Notice of... Domestic Assistance Program Nos. 93.375, Minority Biomedical Research Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics...
78 FR 11896 - National Institute of General Medical Sciences; Notice of Closed Meeting
2013-02-20
... HUMAN SERVICES National Institutes of Health National Institute of General Medical Sciences; Notice of... Domestic Assistance Program Nos. 93.375, Minority Biomedical ] Research Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics...
76 FR 62815 - National Institute of General Medical Sciences Notice of Closed Meeting
2011-10-11
... HUMAN SERVICES National Institutes of Health National Institute of General Medical Sciences Notice of... Nos. 93.375, Minority Biomedical Research Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and Developmental...
76 FR 62815 - National Institute of General Medical Sciences; Notice of Closed Meeting
2011-10-11
... HUMAN SERVICES National Institutes of Health National Institute of General Medical Sciences; Notice of... Nos. 93.375, Minority Biomedical Research Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and Developmental...
76 FR 68486 - National Institute of General Medical Sciences Notice of Closed Meeting
2011-11-04
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2011-11-01
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2013-06-28
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2013-02-28
... Program Nos. 93.375, Minority Biomedical Research Support; 93.821, Cell Biology and Biophysics Research; 93.859, Pharmacology, Physiology, and Biological Chemistry Research; 93.862, Genetics and... . Name of Committee: National Institute of General Medical Sciences Special Emphasis Panel; Clinical...
Expansion of Postdoctoral General Dentistry Training: Meeting National Need and Demand.
Journal of Dental Education, 1994
1994-01-01
The American Association of Dental Schools' policy statement concerning expansion of postdoctoral general dentistry (PGD) training looks at the association's history, purpose, impact, kinds and quantity of student openings available, demand for training, models for expansion, mandatory training in Europe, accreditation, and finance.…
Application of the dynamical interpretation of general relativity
International Nuclear Information System (INIS)
Deumens, E.
1981-01-01
The paper argues that the gravitational field seen in the fully dynamical way, described here, is a useful tool for understanding some fundamental results in a coherent general relativistic way. (author)
General Safety and Waste Management Related to SAM
The General Safety and Waste Management page offers section-specific safety and waste management details for chemicals, radiochemicals, pathogens, and biotoxins included in EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM).
Luft, Friedrich C
2008-12-01
The High Blood Pressure Research Conference of the American Heart Association is a theoretical meeting for hypertension researchers who direct their attention to hypertension-related basic disease mechanisms. The items that I have selected for this brief review are molecular intracellular receptor function, novel angiotensin (Ang)-related pathways, including Ang-(1-7), the Mas receptor, and angiotensin-converting enzyme 2, oxidative stress, immunity, the (pro)renin receptor, and until now unappreciated signalling pathways, such as the tonicity element binding protein.
Probing Strong-field General Relativity with Gravitational Waves
Pretorius, Frans
We are on the verge of a new era in astrophysics as a world-wide effort to observe the universe with gravitational waves takes hold---ground based laser interferometers (Hz to kHz), pulsar timing (micro to nano Hz), measurements of polarization of the cosmic microwave background (sub-nano Hz), and the planned NASA/ESA mission LISA (.1 mHz to .1 Hz). This project will study the theoretical nature of gravitational waves (GWs) emitted by two sources in the LISA band, namely supermassive-black-hole (SMBH) binary mergers, and extreme-mass-ratio-inspirals (EMRI's)---the merger of a stellar mass black hole, neutron star, or white dwarf with a SMBH. The primary goal will be to ascertain how well LISA, by observing these sources, could answer the following related questions about the fundamental nature of strong-field gravity: Does Einstein's theory of general relativity (GR) describe the geometry of black holes in the universe? What constraints can GW observations of SMBH mergers and EMRIs place on alternative theories of gravity? If there are deviations from GR, are there statistics that could give indications of a deviation if sources are detected using a search strategy based solely on GR waveforms? The primary reasons for focusing on LISA sources to answer these questions are (a) binary SMBH mergers could be detected by LISA with exquisitely high signal-to- noise, allowing enough parameters of the system to be accurately extracted to perform consistency checks of the underlying theory, (b) EMRIs will spend numerous orbits close to the central black hole, and thus will be quite sensitive to even small near-horizon deviations from GR. One approach to develop the requisite knowledge and tools to answer these questions is to study a concrete, theoretically viable alternative to GR. We will focus on the dynamical variant of Chern-Simons modified gravity (CSMG), which is interesting for several reasons, chief among which are (1) that CSMG generically arises in both string
Lake, Kayll
2010-12-01
, Hoenselaers C and Herlt E 2003 Exact Solutions of Einstein's Field Equations (Second Edition) (Cambridge: Cambridge University Press) [2] Pretorius F and Israel W 1998 Class. Quantum Grav.15 2289 [3] Wiltshire D, Visser M and Scott S (ed) 2008 The Kerr Spacetime: Rotating Black Holes in General Relativity (Cambridge: Cambridge University Press) [4] Coley A, Hervik S and Pelavas N 2009 Class. Quantum Grav. 26 025013 [5] Plebański J and Krasiński A 2006 An Introduction to General Relativity and Cosmology (Cambridge: Cambridge University Press)
Entropic uncertainty relation based on generalized uncertainty principle
Hsu, Li-Yi; Kawamoto, Shoichi; Wen, Wen-Yu
2017-09-01
We explore the modification of the entropic formulation of uncertainty principle in quantum mechanics which measures the incompatibility of measurements in terms of Shannon entropy. The deformation in question is the type so-called generalized uncertainty principle that is motivated by thought experiments in quantum gravity and string theory and is characterized by a parameter of Planck scale. The corrections are evaluated for small deformation parameters by use of the Gaussian wave function and numerical calculation. As the generalized uncertainty principle has proven to be useful in the study of the quantum nature of black holes, this study would be a step toward introducing an information theory viewpoint to black hole physics.
Sun, Guo-Hua; Dong, Shi-Hai
2015-06-01
Based on a Hamiltonian identity, we study one-dimensional generalized hypervirial theorem, Blanchard-like (non-diagonal case) and Kramers' (diagonal case) recurrence relations for arbitrary xκ which is independent of the central potential V(x). Some significant results in diagonal case are obtained for special κ in xκ (κ ≥ 2). In particular, we find the orthogonal relation = δn1n2 (κ = 0), = (En1 - En2)2 (κ = 1), En = + (κ = 2) and -4En + + 4 = 0 (κ = 3). The latter two formulas can be used directly to calculate the energy levels. We present useful explicit relations for some well known physical potentials without requiring the energy spectra of quantum system. Supported in part by Project 20150964-SIP-IPN, COFAA-IPN, Mexico
Relativity: An Introduction to Special and General Relativity, 3rd edn
International Nuclear Information System (INIS)
Rendall, Alan
2004-01-01
This book is concerned with mathematical topics related to general relativity. Chapters 1-6 are expositions of a number of parts of mathematics which are important for relativists. The main subjects covered are linear algebra, general topology, manifolds, Lie groups and, in particular detail, the Lorentz group. Chapters 7-13 analyse aspects of the geometrical structure of spacetimes. They focus on symmetries of various types and on properties of curvature. Subjects covered include the Petrov classification, holonomy groups, the relation between metric and curvature, affine vector fields, conformal symmetries, projective symmetries and curvature collineations. This part of the book is a treatise on the (mainly local) geometry of four-dimensional Lorentz manifolds, with attention to energy-momentum tensors of interest in general relativity. In the first six chapters the author has concentrated on giving definitions and statements of theorems, the proofs being left to the references that are quoted. He has clearly put much effort into producing a very smooth exposition which is easy to follow and has succeeded in giving us a readable and informative account of the mathematics covered. At the same time mathematical rigour is strictly observed. He also takes the time to carefully discuss many of the subtleties which arise. This part of the book has the character of a textbook suitable for students of general relativity but experienced researchers will also find it a useful reference and are likely to come across interesting facts they have not met elsewhere. The remaining chapters are more like a research monograph and are influenced by the author's own research interests. More proofs are included. Much of the material in this part will be of interest to a narrower audience of relativists than that of the first part. It should, however, be of interest to those working on exact solutions of the Einstein equations and related topics. It is also the case that most
When West Meets East: Generalizing Theory and Expanding the Conceptual Toolkit of Criminology.
Messner, Steven F
2015-06-01
This paper considers the ways in which established criminological theories born and nurtured in the West might need to be transformed to be applicable to the context of East Asian societies. The analyses focus on two theoretical perspectives-Situational Action Theory and Institutional Anomie Theory-that are located at opposite ends of the continuum with respect to levels of analysis. I argue that the accumulated evidence from cross-cultural psychology and criminological research in East Asian societies raises serious questions about the feasibility of simply transporting these perspectives from the West to the East. Instead, my analyses suggest that the formulation of theoretical explanations of crime that are truly universal will require criminologists to create and incorporate new concepts that are more faithful to the social realities of non-Western societies, societies such as those in East Asia and Asia more generally.
A focus on the ANCRE general meeting of June 12, 2015
International Nuclear Information System (INIS)
Bittoun, Jacques; Alazard, Nathalie; Devezeaux, Jean-Guy; Fabre, Francoise; Genet, Roger; Michel, Laurent; Matlosz, Michael; Boissier, Fabrice; Bernard, Herve
2015-01-01
This document gathers Power Point presentations presented during the ANCRE (National Alliance of Coordination of Research for Energy) general assembly. In the first one, after some recalls about the ANCRE, the author presents the context, an assessment and achievements, international actions and partnerships, some return on experience, and perspectives. The second one presents the financing, missions, activities and action plan of the ANR, the French National Research Agency. The third one reports the ADEME's commitment, activities, strategy, research and development activities, investment programme in the energy and ecologic transition. The fourth contribution presents the missions and objectives, governance, programmes of the EERA (European Energy Research Alliance). The last one describes the progress of 'decarbonization wedges' project
Fundamental optimal relation of a generalized irreversible Carnot ...
Indian Academy of Sciences (India)
The generalized irreversible Carnot heat pump model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat leakage, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities besides heat resistance are characterized by a constant parameter and a ...
Einstein's Unification: General Relativity and the Quest for Mathematical Naturalness
van Dongen, J.A.E.F.
2002-01-01
The aim of the thesis has been to understand Einstein's development and see the historical coherence in his later attitude in physics. The lesson we learned has been straightforward: the key that unlocks the later Einstein lies in the road by which he arrived at the field equations of general
Personality Factors Related to Career Satisfaction among General Practitioners.
Schwartz, Robert H.; Shenoy, Sunil
1994-01-01
A survey of 150 general practice dentists examined the relationship between 6 career interests (scientific, artistic, social, enterprising, conventional, technical) and career satisfaction. Results are presented and compared with findings of other studies of dental students and practitioners. Results suggest that satisfied dentists tended to like…
Bianchi type IX string cosmological model in general relativity
Indian Academy of Sciences (India)
Cosmic strings arise during phase transitions after the big-bang explosion as the temperature goes down below some critical temperature [1–3]. These strings have stress energy and couple in a simple way to the gravitational field. The general relativistic formalism of cosmic strings is due to Letelier [4,5]. Stachel [6] has ...
A chiral alternative to the vierbein field in general relativity
Hooft, G. 't
1991-01-01
An alternative to the usual vierbein field in a (3 + 1)-dimensional (euclidean) space-time is proposed such that the internal index takes only three values and the external is a double: ea = −ea. In flat space-time this field reduces to the self-dual generalized Levi-Civita symbol a. Like the
General and special education teachers' relations within teamwork ...
African Journals Online (AJOL)
define team as a group whose members share the same goal which they have esta- ... The team is a group of people with complementary skills who are equally ... management. Cooperative teaching is described as "an educational approach in which general and special educators work in co-active and coordinated fashion ...
General and special education teachers' relations within teamwork ...
African Journals Online (AJOL)
However, the transition, from traditional to inclusive education, brings the problem of general education teachers' professional identity (p = 0.043) and the meaning of interrelations with special education teachers, the significance of teamwork in broader social sense, and the benefits of teamwork outside the institution (p ...
International Nuclear Information System (INIS)
2000-01-01
These proceedings, for the first time, present jointly the 12. Brazilian national meeting on reactor physics and thermal hydraulics (12 ENFIR), 8. General congress on nuclear energy (8. CGEN), and 5. Brazilian national meeting on nuclear applications (5. ENAN). The main theme of discussion was: 'Nuclear Future: thinking for building'. The papers have analysed the progresses of peaceful utilization of nuclear technology and its forecasting for the beginning of the new millennium. The construction of Angra-3 nuclear power plant have been discussed
Nuclear power plant control room ventilation system design for meeting general criterion 19
International Nuclear Information System (INIS)
Murphy, K.G.; Campe, K.M.
1975-01-01
The requirement for protection of control room personnel against radiation is specified in General Design Criterion 19 of Appendix A, 10 CFR Part 50. The evaluation of a control room design, especially its emergency ventilation system, with respect to radiation protection primarily consists of determining the radiation doses to control room personnel under accident conditions. The accident dose assessment involves modeling and evaluation of radiological source terms, atmospheric transport of airborne activity, and protection features of the control room ventilation system. Some of the assumptions and conservatisms used in the dose analyses are based on the technical review experience of existing or proposed control room designs. A review of over 50 control room designs has revealed a great variety of design concepts, not all of which seem to have been based on radiation protection criteria. A summary of the basic control room protection requirements, design features, dose acceptance criteria, and an outline of the methods used by the Regulatory staff for accident dose evaluation are presented. (U.S.)
Rural general practitioner apprehension about work related violence in australia.
Tolhurst, Helen; Talbot, Jane; Baker, Louise; Bell, Pam; Murray, Gillian; Sutton, Amber; Dean, Sarah; Treloar, Carla; Harris, Gillian
2003-10-01
To identify levels of Australian rural general practitioners' apprehension about violence, factors effecting apprehension and the effect of apprehension on service provision. Six focus groups were held with rural GPs from Western Australia, New South Wales and Victoria. A questionnaire was developed on the basis of the focus group data and all GPs in these three areas were surveyed. The results indicated GPs were more apprehensive about providing after hours care than during business hours. Significant gender differences were found with women being more often apprehensive than men and more likely to withdraw after hours services. This study shows that that levels of apprehension about violence affect GPs' willingness to provide after hours services. Future provision of general practice after hours services and home visits in rural areas requires the availability of a safe working environment to reduce GPs' apprehension about workplace violence.
Computational Algorithm for Covariant Series Expansions in General Relativity
Directory of Open Access Journals (Sweden)
Potashov Ivan
2018-01-01
Full Text Available We present a new algorithm for computing covariant power expansions of tensor fields in generalized Riemannian normal coordinates, introduced in some neighborhood of a parallelized k-dimensional submanifold (k = 0, 1, . . .< n; the case k = 0 corresponds to a point, by transforming the expansions to the corresponding Taylor series. For an arbitrary real analytic tensor field, the coefficients of such series are expressed in terms of its covariant derivatives and covariant derivatives of the curvature and the torsion. The algorithm computes the corresponding Taylor polynomials of arbitrary orders for the field components and is applicable to connections that are, in general, nonmetric and not torsion-free. We show that this computational problem belongs to the complexity class LEXP.
2010-04-01
... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Meetings. 401.5 Section 401.5 Foreign Relations INTERNATIONAL JOINT COMMISSION, UNITED STATES AND CANADA RULES OF PROCEDURE General § 401.5 Meetings. (a... meeting shall be open to the public, it shall give such advance notice to this effect as it considers...
General Theory of Relativity - The Power of Speculative Thought
Indian Academy of Sciences (India)
As readers would be aware,· Einstein presented his Special Theory of Relativity in 1905. It soon became clear that while this theory could en- compass mechanics and electromagnetism, grav- ity lay beyond its reach. The effort to recon- cile special relativity with Newtonian gravitation theory turned out to be exceptionally ...
Directors General of Europe's research organisations at the EIROforum meeting, CERN 24/10/2001
BRICE M.
2001-01-01
from left to right: Dr.J. Pamela, EFDA (European Fusion Development Agreement) Associate Leader for JET ( JET-EFDA) Dr. C. Carlile, DG Institut Laue-Langevin (ILL) Dr. A. Mitsos, DG Research, European Commission Prof. L. Maiani, DG CERN Dr. C. Cesarsky, DG European Southern Observatory (ESO) Prof. F. Kafatos, DG European Molecular Biology Laboratory (EMBL) Prof. W.G. Stirling, DG European Snchrotron Radiation Facility (ESRF) Dr.J.P. Poncelet, Director of Strategy and External Relations ESA (European Space Agency)
Content of General Education in Relation to Occupational Training. Country Experiences.
United Nations Educational, Scientific and Cultural Organization, Bangkok (Thailand). Principal Regional Office for Asia and the Pacific.
Studies were conducted in 10 countries of Asia and the Pacific (Australia, China, India, Malaysia, Pakistan, the Philippines, Republic of Korea, Socialist Republic of Viet Nam, Thailand, and Turkey) to determine whether general education school leavers are able to meet the requirements of various occupational training programs. Each country…
Nonextensive kinetic theory and H-theorem in general relativity
Santos, A. P.; Silva, R.; Alcaniz, J. S.; Lima, J. A. S.
2017-11-01
The nonextensive kinetic theory for degenerate quantum gases is discussed in the general relativistic framework. By incorporating nonadditive modifications in the collisional term of the relativistic Boltzmann equation and entropy current, it is shown that Tsallis entropic framework satisfies a H-theorem in the presence of gravitational fields. Consistency with the 2nd law of thermodynamics is obtained only whether the entropic q-parameter lies in the interval q ∈ [ 0 , 2 ] . As occurs in the absence of gravitational fields, it is also proved that the local collisional equilibrium is described by the extended Bose-Einstein (Fermi-Dirac) q-distributions.
Local Lorentz transformations and Thomas effect in general relativity
Silenko, Alexander J.
2016-06-01
The tetrad method is used for an introduction of local Lorentz frames and a detailed analysis of local Lorentz transformations. A formulation of equations of motion in local Lorentz frames is based on the Pomeransky-Khriplovich gravitoelectromagnetic fields. These fields are calculated in the most important special cases and their local Lorentz transformations are determined. The local Lorentz transformations and the Pomeransky-Khriplovich gravitoelectromagnetic fields are applied for a rigorous derivation of a general equation for the Thomas effect in Riemannian spacetimes and for a consideration of Einstein's equivalence principle and the Mathisson force.
Gravitational field of compact objects in general relativity
Boshkayev, Kuantay; Quevedo, Hernando; Ruffini, Remo
2012-09-01
We study some exact and approximate solutions of Einstein’s equations that can be used to describe the gravitational field of astrophysical compact objects in the limiting case of slow rotation and slight deformation. First, we show that none of the standard models obtained by using Fock’s method can be used as an interior source for the approximate exterior Kerr solution. We then use Fock’s method to derive a generalized interior solution, and also an exterior solution that turns out to be equivalent to the exterior Hartle-Thorne approximate solution that, in turn, is equivalent to an approximate limiting case of the exact Quevedo-Mashhoon solution. As a result we obtain an analytic approximate solution that describes the interior and exterior gravitational field of a slowly rotating and slightly deformed astrophysical object.
Hamiltonian formalism for perfect fluids in general relativity
International Nuclear Information System (INIS)
Demaret, J.; Moncrief, V.
1980-01-01
Schutz's Hamiltonian theory of a relativistic perfect fluid, based on the velocity-potential version of classical perfect fluid hydrodynamics as formulated by Seliger and Whitham, is used to derive, in the framework of the Arnowitt, Deser, and Misner (ADM) method, a general partially reduced Hamiltonian for relativistic systems filled with a perfect fluid. The time coordinate is chosen, as in Lund's treatment of collapsing balls of dust, as minus the only velocity potential different from zero in the case of an irrotational and isentropic fluid. A ''semi-Dirac'' method can be applied to quantize astrophysical and cosmological models in the framework of this partially reduced formalism. If one chooses Taub's adapted comoving coordinate system, it is possible to derive a fully reduced ADM Hamiltonian, which is equal to minus the total baryon number of the fluid, generalizing a result previously obtained by Moncrief in the more particular framework of Taub's variational principle, valid for self-gravitating barotropic relativistic perfect fluids. An unconstrained Hamiltonian density is then explicitly derived for a fluid obeying the equation of state p=(gamma-1)rho (1 < or = γ < or = 2), which can adequately describe the phases of very high density attained in a catastrophic collapse or during the early stages of the Universe. This Hamiltonian density, shown to be equivalent to Moncrief's in the particular case of an isentropic fluid, can be simplified for fluid-filled class-A diagonal Bianchi-type cosmological models and appears as a suitable starting point for the study of the canonical quantization of these models
Numerical Hydrodynamics in Strong-Field General Relativity
East, William Edward
In this thesis we develop and test methods for numerically evolving hydrodynamics coupled to the Einstein field equations, and then apply them to several problems in gravitational physics and astrophysics. The hydrodynamics scheme utilizes high-resolution shock-capturing techniques with flux corrections while the Einstein equations are evolved in the generalized harmonic formulation using finite difference methods. We construct initial data by solving the constraint equations using a multigrid algorithm with free data chosen based on superposing isolated compact objects. One application we consider is the merger of black hole-neutron star and neutron star-neutron star binaries that form through dynamical capture, as may occur in globular clusters or galactic nuclei. These systems can merge with non-negligible orbital eccentricity and display significant variability in dynamics and outcome as a function of initial impact parameter. We study the electromagnetic and gravitational-wave transients that these mergers may produce and their prospects for being detected with upcoming observations. We also introduce a numerical technique that allows solutions to the full Einstein equations to be obtained for extreme-mass-ratio systems where the spacetime is dominated by a known background solution. This technique is based on using the knowledge of a background solution to subtract off its contribution to the truncation error. We use this to study the tidal effects and gravitational radiation from a solar-type star falling into a supermassive black hole. Finally, we utilize general-relativistic hydrodynamics to study ultrarelativistic black hole formation. We study the head-on collision of fluid particles well within the kinetic energy dominated regime (Lorentz factors of 8-12). We find that black hole formation does occur at energies a factor of a few below simple hoop conjecture estimates. We also find that near the threshold for black hole formation, the collision leads to
9th International Conference on General Relativity and Gravitation
International Nuclear Information System (INIS)
Schmutzer, E.
1980-01-01
Volume 3 presents the abstracts of the following discussion groups: Quantization about classical background metrics (36 abstracts); Supergravity, renormalization program (8 abstracts); Classical gauge type theories of gravity (23 abstracts). 14 abstracts not related to any discussion group and 5 later submitted abstracts are also included. An alphabetic author index is given
Fundamental optimal relation of a generalized irreversible Carnot ...
Indian Academy of Sciences (India)
to the real heat pump than the endoreversible Carnot heat pump model. And they derived its fundamental optimal relation between heating load and COP [36–. 38] and the ecological optimal performance [39] with Newtonian heat transfer law. Kodal et al [40] investigated the finite-time thermoeconomic optimization for the.
Static charged spheres with anisotropic pressure in general relativity
Indian Academy of Sciences (India)
relativity. *. J KRISHNA RAO*, M ANNAPURNA and M M TRIVEDI. Department of Mathematics, Bhavnagar University, Bhavnagar 364 002, India. /nobr>. Department of Mathematics, Vasavi Engineering College, Hyderabad 500 031, India. £. Address for correspondence: 302, Surya Enclave, Asif Nagar, Mehdipatnam, ...
Special relativity in general frames from particles to astrophysics
Gourgoulhon, Éric
2013-01-01
Special relativity is the basis of many fields in modern physics: particle physics, quantum field theory, high-energy astrophysics, etc. This theory is presented here by adopting a four-dimensional point of view from the start. An outstanding feature of the book is that it doesn’t restrict itself to inertial frames but considers accelerated and rotating observers. It is thus possible to treat physical effects such as the Thomas precession or the Sagnac effect in a simple yet precise manner. In the final chapters, more advanced topics like tensorial fields in spacetime, exterior calculus and relativistic hydrodynamics are addressed. In the last, brief chapter the author gives a preview of gravity and shows where it becomes incompatible with Minkowsky spacetime. Well illustrated and enriched by many historical notes, this book also presents many applications of special relativity, ranging from particle physics (accelerators, particle collisions, quark-gluon plasma) to astrophysics (relativistic jets, active g...
Measuring Health-Related Quality of Life: General Issues
Guyatt, Gordon H
1997-01-01
Clinicians and policy makers recognize the importance of measuring health-related quality of life (HRQL) to make informed patient management and policy decisions. Self- or interviewer-administered questionnaires can be used to measure cross-sectional differences in quality of life among patients at a point in time (discriminative instruments) or longitudinal changes in HRQL within patients over time (evaluative instruments). Both discriminative and evaluative instruments must be valid (ie, me...
General Relativity eliminates Dark Energy, Dark Matter and Universal Expansion
Bartlett, Rodney
2018-01-01
This letter was rejected by International Knowledge Press because "we are unable to conclude that these findings would warrant publication in this journal." The letter is suggesting that dark energy, dark matter and universal expansion are intimately related. However, they aren't viewed as revolutions in cosmology which are essential to a complete understanding of the modern universe. They are instead viewed as properties which need to be added to the cosmos when Einstein...
Hydrodynamics in full general relativity with conservative AMR
East, William E.; Pretorius, Frans; Stephens, Branson C.
2011-01-01
There is great interest in numerical relativity simulations involving matter due to the likelihood that binary compact objects involving neutron stars will be detected by gravitational wave observatories in the coming years, as well as to the possibility that binary compact object mergers could explain short-duration gamma-ray bursts. We present a code designed for simulations of hydrodynamics coupled to the Einstein field equations targeted toward such applications. This code has recently be...
International Nuclear Information System (INIS)
2013-01-01
The objectives of the meeting were: • To identify the main issues and technical features that affect capital and energy production costs of fast reactors and related fuel cycle facilities; • To present fast reactor concepts and designs with enhanced economic characteristics, as well as innovative technical solutions (components, subsystems, etc.) that have the potential to reduce the capital costs of fast reactors and related fuel cycle facilities; • To present energy models and advanced tools for the cost assessment of innovative fast reactors and associated nuclear fuel cycles; • To discuss the results of studies and ongoing R&D activities that address cost reduction and the future economic competitiveness of fast reactors; • To identify research and technology development needs in the field, also in view of new IAEA initiatives to help and support Member States in improving the economic competitiveness of fast reactors and associated nuclear fuel cycles
International Nuclear Information System (INIS)
2013-01-01
The objectives of the meeting were: - To identify the main issues and technical features that affect capital and energy production costs of fast reactors and related fuel cycle facilities; - To present fast reactor concepts and designs with enhanced economic characteristics, as well as innovative technical solutions (components, subsystems, etc.) that have the potential to reduce the capital costs of fast reactors and related fuel cycle facilities; - To present energy models and advanced tools for the cost assessment of innovative fast reactors and associated nuclear fuel cycles; - To discuss the results of studies and on-going R&D activities that address cost reduction and the future economic competitiveness of fast reactors; and - To identify research and technology development needs in the field, also in view of new IAEA initiatives to help and support Member States in improving the economic competitiveness of fast reactors and associated nuclear fuel cycles
Uniformly rotating, axisymmetric, and triaxial quark stars in general relativity
Zhou, Enping; Tsokaros, Antonios; Rezzolla, Luciano; Xu, Renxin; UryÅ«, KÅji
2018-01-01
Quasiequilibrium models of uniformly rotating axisymmetric and triaxial quark stars are computed in a general-relativistic gravity scenario. The Isenberg-Wilson-Mathews (IWM) formulation is employed and the Compact Object Calculator (cocal) code is extended to treat rotating stars with finite surface density and new equations of state (EOSs). Besides the MIT bag model for quark matter which is composed of deconfined quarks, we examine a new EOS proposed by Lai and Xu that is based on quark clustering and results in a stiff EOS that can support masses up to 3.3 M⊙ in the case we considered. We perform convergence tests for our new code to evaluate the effect of finite surface density in the accuracy of our solutions and construct sequences of solutions for both small and high compactness. The onset of secular instability due to viscous dissipation is identified and possible implications are discussed. An estimate of the gravitational wave amplitude and luminosity based on quadrupole formulas is presented and comparison with neutron stars is discussed.
Modeling of charged anisotropic compact stars in general relativity
Energy Technology Data Exchange (ETDEWEB)
Dayanandan, Baiju; Maurya, S.K.; T, Smitha T. [University of Nizwa, Department of Mathematical and Physical Sciences, College of Arts and Science, Nizwa (Oman)
2017-06-15
A charged compact star model has been determined for anisotropic fluid distribution. We have solved the Einstein-Maxwell field equations to construct the charged compact star model by using the radial pressure, the metric function e{sup λ} and the electric charge function. The generic charged anisotropic solution is verified by exploring different physical conditions like causality condition, mass-radius relation and stability of the solution (via the adiabatic index, TOV equations and the Herrera cracking concept). It is observed that the present charged anisotropic compact star model is compatible with the star PSR 1937+21. Moreover, we also presented the EOS ρ = f(p) for the present charged compact star model. (orig.)
Generality of a congruity effect in judgements of relative order.
Liu, Yang S; Chan, Michelle; Caplan, Jeremy B
2014-10-01
The judgement of relative order (JOR) procedure is used to investigate serial-order memory. Measuring response times, the wording of the instructions (whether the earlier or the later item was designated as the target) reversed the direction of search in subspan lists (Chan, Ross, Earle, & Caplan Psychonomic Bulletin & Review, 16(5), 945-951, 2009). If a similar congruity effect applied to above-span lists and, furthermore, with error rate as the measure, this could suggest how to model order memory across scales. Participants performed JORs on lists of nouns (Experiment 1: list lengths = 4, 6, 8, 10) or consonants (Experiment 2: list lengths = 4, 8). In addition to the usual distance, primacy, and recency effects, instructions interacted with serial position of the later probe in both experiments, not only in response time, but also in error rate, suggesting that availability, not just accessibility, is affected by instructions. The congruity effect challenges current memory models. We fitted Hacker's (Journal of Experimental Psychology: Human Learning and Memory, 6(6), 651-675, 1980) self-terminating search model to our data and found that a switch in search direction could explain the congruity effect for short lists, but not longer lists. This suggests that JORs may need to be understood via direct-access models, adapted to produce a congruity effect, or a mix of mechanisms.
Generalized fluctuation relation for power-law distributions.
Budini, Adrián A
2012-07-01
Strong violations of existing fluctuation theorems may arise in nonequilibrium steady states characterized by distributions with power-law tails. The ratio of the probabilities of positive and negative fluctuations of equal magnitude behaves in an anomalous nonmonotonic way [H. Touchette and E. G. D. Cohen, Phys. Rev. E 76, 020101(R) (2007)]. Here, we propose an alternative definition of fluctuation relation (FR) symmetry that, in the power-law regime, is characterized by a monotonic linear behavior. The proposal is consistent with a large deviationlike principle. As an example, we study the fluctuations of the work done on a dragged particle immersed in a complex environment able to induce power-law tails. When the environment is characterized by spatiotemporal temperature fluctuations, distributions arising in nonextensive statistical mechanics define the work statistics. In that situation, we find that the FR symmetry is solely defined by the average bath temperature. The case of a dragged particle subjected to a Lévy noise is also analyzed in detail.
Scientific Meetings Database: A New Tool for CTBT-Related International Cooperation
Energy Technology Data Exchange (ETDEWEB)
Knapik, Jerzy F.; Girven, Mary L.
1999-08-20
The mission of international cooperation is defined in the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Ways and means of implementation were the subject of discussion during the International Cooperation Workshop held in Vienna in November 1998, and during the Regional Workshop for CTBTO International Cooperation held in Cairo, Egypt in June 1999. In particular, a database of ''Scientific and Technical Meetings Directly or Indirectly Related to CTBT Verification-Related Technologies'' was developed by the CTBTO PrepCom/PTS/International Cooperation section and integrated into the organization's various web sites in cooperation with the U.S. Department of Energy CTBT Research and Development Program. This database, the structure and use of which is described in this paper/presentation is meant to assist the CTBT-related scientific community in identifying worldwide expertise in the CTBT verification-related technologies and should help experts, particularly those of less technologically advanced States Signatories, to strengthen contacts and to pursue international cooperation under the Tredy regime. Specific opportunities for international cooperation, in particular those provided by active participation in the use and further development of this database, are presented in this paper and/or presentation.
Topics in the Foundations of General Relativity and Newtonian Gravitation Theory
Malament, David B
2012-01-01
In Topics in the Foundations of General Relativity and Newtonian Gravitation Theory, David B. Malament presents the basic logical-mathematical structure of general relativity and considers a number of special topics concerning the foundations of general relativity and its relation to Newtonian gravitation theory. These special topics include the geometrized formulation of Newtonian theory (also known as Newton-Cartan theory), the concept of rotation in general relativity, and Gödel spacetime. One of the highlights of the book is a no-go theorem that can be understood to show that there is
PREFACE: Spanish Relativity Meeting/ERE2009Gravitation in the Large
Lazkoz, Ruth; Vera, Raül
2010-04-01
Scientists working in Relativity, Gravitation and Cosmology in Spanish institutions have been organising the Spanish Relativity Meetings (ERE) for more than 30 years now, and 2009 was the turn of the group at the University of the Basque Country (UPV/EHU) to continue this well established tradition. There is no doubt these meetings have become a benchmark in the field not only because of the high scientific level reached in each edition, but also because of the almost legendary relaxed atmosphere. The support of our sponsors --Spanish Ministry of Science and Innovation, through the funding actions FIS2008-03716-E and FIS2008-04494-E, Basque Government, UPV/EHU, and Spanish Relativity and Gravitation Society (SEGRE)-- and specially the scientific and social contributions of all the participants turned the ERE2009 a memorable edition for us, and we hope this is also the impression of everyone else involved in this meeting. The organising committee was very pleased to present an excellent panel of invited speakers to dissert on four topics that are gathering enormous interest and activity: Quantum and thermodynamical effects in Gravity, Modern Cosmology, Numerical Relativity and Black holes. But the meeting also boasted a high scientific level thanks to the more than a hundred other participants from many different countries whose enthusiasm was an excellent proof of the good health of Relativity, Gravitation and Cosmology as a research area. The scientific programme started on the 7th, with an opening by a representative of the Principal of the University of the Basque Country, along with the Deputy Mayor of Bilbao, and the Chair of the conference, José M.M. Senovilla. Lectures were delivered on the 7th, 8th, 9th and 11th of September 2009 following a scheme of plenary sessions in the morning (the first lecture always being an invited one) and two parallel sessions in the afternoon. There were of course coffee-breaks to refresh bodies and spirits and encourage the
Bergen, J.E.A.M. van; Kerssens, J.J.; Schellevis, F.G.; Sandfort, T.G.; Coenen, T.J.; Bindels, P.J.
2006-01-01
Background: The role of the GP in the care of sexually transmitted infections (STIs) is unclear.Aim:We studied the prevalence of STI related consultations in Dutch general practice in order to obtain insight into the contribution of the GP in STI control.Design of study: A descriptive
van Bergen, Jan E. A. M.; Kerssens, Jan J.; Schellevis, Francois G.; Sandfort, Theo G.; Coenen, Ton J.; Bindels, Patrick J.
2006-01-01
BACKGROUND: The role of the GP in the care of sexually transmitted infections (STIs) is unclear.Aim:We studied the prevalence of STI related consultations in Dutch general practice in order to obtain insight into the contribution of the GP in STI control. DESIGN OF STUDY: A descriptive study.
International Nuclear Information System (INIS)
2000-01-01
These proceedings, for the first time, present jointly the 12. Brazilian national meeting on reactor physics and thermal hydraulics (12. ENFIR), the 8. General congress on nuclear energy (8. CGEN), and the 5. Brazilian national meeting on nuclear applications (5. ENAN). The main theme of discussion was: 'Nuclear Future: thinking for building'. The papers have analysed the progresses of peaceful utilization of nuclear technology and its forecasting for the beginning of the new millennium. The construction of Angra-3 nuclear power plant have been discussed
4-Dimensional General Relativity from the instrinsic spatial geometry of SO(3) Yang--Mills theory
Ita III, Eyo Eyo
2007-01-01
In this paper we derive 4-dimensional General Relativity from three dimensions, using the intrinsic spatial geometry inherent in Yang--Mills theory which has been exposed by previous authors as well as as some properties of the Ashtekar variables. We provide various interesting relations, including the fact that General Relativity can be written as a Yang--Mills theory where the antiself-dual Weyl curvature replaces the Yang--Mills coupling constant. We have generalized the results of some pr...
Cassidy, George W.
1979-01-01
Interest and pressure group activity is analyzed in the context of state public employee relations laws and state "open meeting" laws. Suggests that the courts and state labor relations boards are susceptible receptors of pressure- and interest-group influence. (Author/IRT)
Indian Academy of Sciences (India)
Page S20: NMR compound 4i. Page S22: NMR compound 4j. General: Chemicals were purchased from Fluka, Merck and Aldrich Chemical Companies. All the products were characterized by comparison of their IR, 1H NMR and 13C NMR spectroscopic data and their melting points with reported values. General procedure ...
Radic-Sestic, Marina; Radovanovic, Vesna; Milanovic-Dobrota, Biljana; Slavkovic, Sanela; Langovic-Milicvic, Ana
2013-01-01
The general objective of this study was to establish the relation between general and special education teachers within teamwork and to define socio-demographic factors that affect teamwork. The sample encompassed 223 general and special education teacher of both genders, age 25 to 60, who are employed in regular elementary schools in Serbia. The…
van Bergen, Jan EAM; Kerssens, Jan J; Schellevis, Francois G; Sandfort, Theo G; Coenen, Ton J; Bindels, Patrick J
2006-01-01
Background The role of the GP in the care of sexually transmitted infections (STIs) is unclear. Aim We studied the prevalence of STI related consultations in Dutch general practice in order to obtain insight into the contribution of the GP in STI control. Design of study A descriptive study. Setting The study took place within the framework of the second Dutch National Survey of General Practice in 2001, a large nationally representative population-based survey. Method During 1 year, data of all patient contacts with the participating GPs were recorded in electronic medical records. Contacts for the same health problem were clustered into disease episodes and their diagnosis coded according to the International Classification of Primary Care. All STI and STI related episodes were analysed. Results In total, 1 524 470 contacts of 375 899 registered persons in 104 practices were registered during 1 year and 2460 STI related episodes were found. The prevalence rate of STI was 39 per 10 000 persons and of STI/HIV related questions 23 per 10 000. More than half of all STIs were found in highly urbanised areas and STIs were overrepresented in deprived areas. Three quarters of all STIs diagnosed in the Netherlands are made in general practice. An important number of other reproductive health visits in general practice offer opportunities for meaningful STI counselling and tailored prevention. Discussion GPs contribute significantly to STI control, see the majority of patients with STI related symptoms and questions and are an important player in STI care. In particular, GPs in urban areas and inner-city practices should be targeted for accelerated sexual health programmes. PMID:16464323
Wisconsin Univ., Madison. Industrial Relations Research Inst.
This meeting was held to exchange views on organization, operation, and goals of industrial relations centers, institutes, and schools. The opening speaker outlined the structure and functions of the international organization and of the regional conferences. The first paper, "Administrative Arrangements in Industrial Relations Centers," was based…
4-dimensional General Relativity from the instrinsic spatial geometry of SO(3) Yang-Mills theory
International Nuclear Information System (INIS)
Ita, Eyo Eyo
2011-01-01
In this paper we derive 4-dimensional General Relativity from three dimensions, using the intrinsic spatial geometry inherent in Yang-Mills theory which has been exposed by previous authors as well as some properties of the Ashtekar variables. We provide various interesting relations, including the fact that General Relativity can be written as a Yang-Mills theory where the antiself-dual Weyl curvature replaces the Yang-Mills coupling constant. We have generalized the results of some previous authors, covering Einstein's spaces, to include more general spacetime geometries.
ACADEMIC TRAINING LECTURE SERIES: Introduction to General Relativity and Black Holes
2003-01-01
10, 11, 12, 13, 14 February ACADEMIC TRAINING LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Introduction to General Relativity and Black Holes by T.DAMOUR, IHES, Bures-sur-Yvette, F - Physical motivation behind Einstein's theory. - Mathematical formalism of General Relativity. - Experimental confirmations of Einstein's theory. - Introduction to Black Holes physics.
29 CFR 541.201 - Directly related to management or general business operations.
2010-07-01
... management or general business operations. (a) To qualify for the administrative exemption, an employee's... operations of the employer or the employer's customers. The phrase “directly related to the management or... 29 Labor 3 2010-07-01 2010-07-01 false Directly related to management or general business...
General relativity the most beautiful of theories : applications and trends after 100 years
2015-01-01
Generalising Newton's law of gravitation, general relativity is one of the pillars of modern physics. On the occasion of general relativity's centennial, leading scientists in the different branches of gravitational research review the history and recent advances in the main fields of applications of the theory, which was referred to by Lev Landau as “the most beautiful of the existing physical theories”.
Directory of Open Access Journals (Sweden)
Peter D. Hart
2017-01-01
Full Text Available Objectives The purpose of this study was to examine the relationship of meeting the recommended levels of physical activity (PA with health status and preventive health behavior in adults. Methods A total of 5630 adults 18 years of age or older were included in this study. PA was assessed using a series of questions that categorized activities based on their metabolic equivalent values and then categorized individuals based on the reported frequency and duration of such activities. Participants reporting 150 minutes or more of moderate-intensity PA per week were considered to have met the PA guidelines. Multiple logistic regression was used to model the relationships between meeting PA guidelines and health status and preventive health behavior, while controlling for confounding variables. Results Overall, 53.9% (95% confidence interval [CI], 51.9 to 55.9% of adults reported meeting the recommended levels of PA. Among adults with good general health, 56.9% (95% CI, 54.7 to 59.1% reported meeting the recommended levels of PA versus 43.1% (95% CI, 40.9 to 45.3% who did not. Adults who met the PA guidelines were significantly more likely not to report high cholesterol, diabetes, chronic obstructive pulmonary disease, arthritis, asthma, depression, or overweight. Furthermore, adults meeting the PA guidelines were significantly more likely to report having health insurance, consuming fruits daily, consuming vegetables daily, and not being a current cigarette smoker. Conclusions In this study, we found meeting the current guidelines for PA to have a protective relationship with both health status and health behavior in adults. Health promotion programs should focus on strategies that help individuals meet the current guidelines of at least 150 minutes per week of moderate-intensity PA.
Dwelle, M. C.
2014-12-01
Water is the source for pressures throughout the world as supplies of freshwater become more scarce and stressed. These pressures can be realized through the lens of water science, policy, geopolitics, food security, and even military conflicts. Combined with a boom in global population, these pressures provide wide-reaching problems that need to be addressed presently and in the future across many disciplines including the sciences, engineering, economics, and policy. These issues lead to a complex system of problems that cannot be addressed without a multidisciplinary approach. As we enter a world where regions of water scarcity become the norm, water scientists and engineers need to be at the table - with experts in other fields - shaping solutions in the areas of policy, disaster response, and management. I will argue that, as early-career scientists, there are exciting new challenges that are open, or will be opening, to us as experts in our respective fields. I will also provide my insights and opinions as to what we can do to position ourselves to impact these issues. These beliefs form the basis of the "Renaissance scientist," taking its name from the polymaths of the Renaissance and Enlightenment. The name suggests that we need to not only leverage our own area expertise, but also be able to effectively learn from and communicate with experts in seemingly diverse fields to meet the world's water-related challenges.
Carnero, Elena; Díez, Juana; Fortes, Purificación; Gastaminza, Pablo; Majano, Pedro; Martínez, Miguel Angel; Pérez-del-Pulgar, Sofía; Quer, Josep; López-Labrador, F Xavier
2013-12-01
The hepatitis C virus (HCV) was discovered by the team of Michael Houghton at Chiron Corporation in 1989 and the first symposium on HCV and related viruses was held in Venice, Italy, shortly after, in 1992. This conference was organized to advance knowledge on what then was a mysterious virus responsible for most cases of «non-A, non-B» hepatitis. During the 20 years since the first conference, the scientific quality of presentations has steadily increased, together with the tremendous advances in basic and clinical research and epidemiology. What started as a small conference on a new virus, about which there were very few data, has today become a first-in-class congress: a meeting place for basic researchers, clinicians, epidemiologists, public health experts, and industry members to present the most important advances and their application to HCV treatment and control. The nineteenth HCV symposium was held in September 2012, once again in Venice. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.
Philipp, M; Vergnat, C; Müller, U; Sanctuary, R; Baller, J; Possart, W; Alnot, P; Krüger, J K
2009-01-21
The non-equilibrium process of polymerization of reactive polymers can be accompanied by transition phenomena like gelation or the chemical glass transition. The sensitivity of the mechanical properties at hypersonic frequencies-including the generalized Cauchy relation-to these transition phenomena is studied for three different polyurethanes using Brillouin spectroscopy. As for epoxies, the generalized Cauchy relation surprisingly holds true for the non-equilibrium polymerization process and for the temperature dependence of polyurethanes. Neither the sol-gel transition nor the chemical and thermal glass transitions are visible in the representation of the generalized Cauchy relation. Taking into account the new results and combining them with general considerations about the elastic properties of the isotropic state, an improved physical foundation of the generalized Cauchy relation is proposed.
Smalley, L. L.
1983-01-01
The proper framework for testing Rastall's theory and its generalizations is in the case of non-negligible (i.e. discernible) gravitational effects such as gravity gradients. These theories have conserved integral four-momentum and angular momentum. The Nordtvedt effect then provides limits on the parameters which arise as the result of the non-zero divergence of the energy-momentum tensor.
DEFF Research Database (Denmark)
Lundstrøm, Sanne Lykke; Edwards, Kasper; Reventlow, Susanne
2014-01-01
In this paper we investigate the association between relational coordination among the practice team in general practice and number of consultations performed in a general practice per staff, i.e. a proxy of productivity. We measured relational coordination using the Relational Coordination Survey...... and combined the results with register data. We found that relational coordination was statistically significant associated with number of consultation per staff per year. We later divided consultations in to three types: Face-to-face, Email and phone consultations. We found a statistically significant...... associating between relational coordination and with number of face-to-face consultation per staff per year....
Thornton, Daniel H; Branch, Lyn C; Sunquist, Melvin E
2011-09-01
The relative influence of habitat loss vs. habitat fragmentation per se (the breaking apart of habitat) on species distribution and abundance is a topic of debate. Although some theoretical studies predict a strong negative effect of fragmentation, consensus from empirical studies is that habitat fragmentation has weak effects compared with habitat loss and that these effects are as likely to be positive as negative. However, few empirical investigations of this issue have been conducted on tropical or wide-ranging species that may be strongly influenced by changes in patch size and edge that occur with increasing fragmentation. We tested the relative influence of habitat loss and fragmentation by examining occupancy of forest patches by 20 mid- and large-sized Neotropical mammal species in a fragmented landscape of northern Guatemala. We related patch occupancy of mammals to measures of habitat loss and fragmentation and compared the influence of these two factors while controlling for patch-level variables. Species responded strongly to both fragmentation and loss, and response to fragmentation generally was negative. Our findings support previous assumptions that conservation of large mammals in the tropics will require conservation strategies that go beyond prevention of habitat loss to also consider forest cohesion or other aspects of landscape configuration.
Muschalla, Beate; Glatz, Johannes; Linden, Michael
2014-01-01
Absence of an adequate reason for anxiety is a criterion for pathological anxiety. However, the presence of danger or fear-provoking stimuli may even be a risk factor for anxiety and does not exclude that there is additionally pathological anxiety too. The question is, to what degree can heart-related anxiety be explained by the severity of illness or trait anxiety? Two hundred and nine patients (37.8% women) from a cardiology inpatient unit completed the Heart-Anxiety-Questionnaire, Progression-Anxiety-Questionnaire, Job-Anxiety-Scale and the State-Trait-Anxiety-Inventory. The severity of cardiac illness was rated by the treating cardiologists using the Multidimensional Severity of Morbidity Rating. Time absent from work due to sickness was assessed as an indicator for illness-related impairment. Heart anxiety was significantly related to progression anxiety and, to a lesser extent, trait anxiety and indicators of subjective symptoms of somatic illness. No association was found with medical ratings for prognosis, multimorbidity, or reduction in life expectancy. Heart-related anxiety is a symptom of an anxiety disorder. Although partially dependent on subjective suffering, it cannot be explained by the severity of medical illness. Treatment of health-related anxieties should focus on how to cope with subjective symptoms of illness.
Generalization of Work-Related Social Behavior for Persons with Mental Retardation.
Black, Rhonda S.; Langone, John
This paper reviews the research and attempts to identify instructional techniques and settings to promote generalization of appropriate work-related social behavior in individuals with mental retardation. First, it provides a definition of transition and discusses the importance of training for generalization, discrimination, and maintenance.…
General movements in the perinatal period and its relation to echogenicity changes in the brain
Rosier-van Dunne, F.M.F.; Wezel-Meijler, G.; Bakker, M.P.; de Groot, L.; Odendaal, H.J.; de Vries, J.I.P.
2010-01-01
Background: In preterm born infants abnormal general movements (GMs) generally normalize before three months post term, but may persist when perinatal brain injury is present. Aims: To assess the continuity of GM quality from fetal to early neonatal period and its relation to brain echogenicity
Racism-Related Stress, General Life Stress, and Psychological Functioning among Black American Women
Pieterse, Alex L.; Carter, Robert T.; Ray, Kilynda V.
2013-01-01
The relationship between general life stress, perceived racism, and psychological functioning was explored in a sample of 118 Black American women. Findings indicate that racism-related stress was not a significant predictor of psychological functioning when controlling for general life stress. Perceived racism was positively associated with…
Propagators of Generalized Schrödinger Equations Related by First-order Supersymmetry
Directory of Open Access Journals (Sweden)
A. Schulze-Halberg
2011-01-01
Full Text Available We construct an explicit relation between propagators of generalized Schrödinger equations that are linked by a first-order supersymmetric transformation. Our findings extend and complement recent results on the conventional case [1].
Gravitational redshift of galaxies in clusters as predicted by general relativity.
Wojtak, Radosław; Hansen, Steen H; Hjorth, Jens
2011-09-28
The theoretical framework of cosmology is mainly defined by gravity, of which general relativity is the current model. Recent tests of general relativity within the Lambda Cold Dark Matter (ΛCDM) model have found a concordance between predictions and the observations of the growth rate and clustering of the cosmic web. General relativity has not hitherto been tested on cosmological scales independently of the assumptions of the ΛCDM model. Here we report an observation of the gravitational redshift of light coming from galaxies in clusters at the 99 per cent confidence level, based on archival data. Our measurement agrees with the predictions of general relativity and its modification created to explain cosmic acceleration without the need for dark energy (the f(R) theory), but is inconsistent with alternative models designed to avoid the presence of dark matter. © 2011 Macmillan Publishers Limited. All rights reserved
Why are predictions of general relativity theory for gravitational effects non-unique?
International Nuclear Information System (INIS)
Loskutov, Yu.M.
1990-01-01
Reasons of non-uniqueness of predictions of the general relativity theory (GRT) for gravitational effects are analyzed in detail. To authors' opinion, the absence of comparison mechanism of curved and plane metrics is the reason of non-uniqueness
International Nuclear Information System (INIS)
Schulze-Halberg, Axel
2010-01-01
We study Green's functions of the generalized Sturm-Liouville problems that are related to each other by Darboux -equivalently, supersymmetrical - transformations. We establish an explicit relation between the corresponding Green's functions and derive a simple formula for their trace. The class of equations considered here includes the conventional Schroedinger equation and generalizations, such as for position-dependent mass and with linearly energy-dependent potential, as well as the stationary Fokker-Planck equation.
Associations of Adolescent Weight Status and Meeting National Obesity-Related Recommendations
Cook, Jessica A.; McCormick, Emily V.; Mickiewicz, Theresa E.; Davidson, Arthur J.; Main, Deborah S.
2017-01-01
Background: Adolescent overweight and obesity are serious health risks, with prevalence varying by sociodemographic group. Studies link children's weight status and sex/race-ethnic differences with meeting recommendations for physical activity and diet. But, research examining the intersection of sociodemographic characteristics, behavior, and…
Mussini, C.; Antinori, A.; Bhagani, S.; Branco, T.; Brostrom, M.; Dedes, N.; Bereczky, T.; Girardi, E.; Gökengin, D.; Horban, A.; Lacombe, K.; Lundgren, J. D.; Mendao, L.; Mocroft, A.; Oprea, C.; Porter, K.; Podlekareva, D.; Battegay, M.; d'Arminio Monforte, A.; Mulcahy, Fiona; Geretti, Anna Maria; Clumeck, Nathan; Reiss, Peter; Arribas, Jose; Gatell, Jose; Katlama, Christine; Pozniak, Anton; Rockstroh, Jürgen; Youle, Mike; Friis-Møller, Nina; Rusconi, Stefano; Behrens, Georg; de Wit, Stéphane; Furrer, Hansjakob; Wensing, Annemarie; John Gill, M.; Letendre, Scott
2016-01-01
The objective of the 1st European AIDS Clinical Society meeting on Standard of Care in Europe was to raise awareness of the European scenario and come to an agreement on actions that could be taken in the future. Data-driven presentations were given on specific topics followed by interactive panel
Mussini, C.; Antinori, A.; Bhagani, S.; Branco, T.; Brostrom, M.; Dedes, N.; Bereczky, T.; Girardi, E.; Gökengin, D.; Horban, A.; Lacombe, K.; Lundgren, J. D.; Mendao, L.; Mocroft, A.; Oprea, C.; Porter, K.; Podlekareva, D.; Battegay, M.; d'Arminio Monforte, A.; Mulcahy, Fiona; Geretti, Anna Maria; Clumeck, Nathan; Reiss, Peter; Arribas, Jose; Gatell, Jose; Katlama, Christine; Pozniak, Anton; Rockstroh, Jürgen; Youle, Mike; Friis-Møller, Nina; Rusconi, Stefano; Behrens, Georg; De Wit, Stéphane; Furrer, Hansjakob; Wensing, Annemarie|info:eu-repo/dai/nl/30817724X; John Gill, M.; Letendre, Scott
2016-01-01
Objectives: The objective of the 1st European AIDS Clinical Society meeting on Standard of Care in Europe was to raise awareness of the European scenario and come to an agreement on actions that could be taken in the future. Methods: Data-driven presentations were given on specific topics followed
2012-10-31
... basis. To join the conference, submit inquiries to Ms. Yvette Springer at Yvette.Springer@bis.doc.gov no... meeting to Ms. Springer via email. For more information, call Yvette Springer at (202) 482 2813. Dated: October 25, 2012. Yvette Springer, Committee Liaison Officer. BILLING CODE P ...
2013-10-23
... basis. To join the conference, submit inquiries to Ms. Yvette Springer at Yvette.Springer@bis.doc.gov no... meeting to Ms. Springer via email. For more information, call Yvette Springer at (202) 482-2813. Dated: October 18, 2013. Yvette Springer, Committee Liaison Officer. BILLING CODE P ...
Safety related design and economic aspects of HTGRs. Proceedings of a technical committee meeting
International Nuclear Information System (INIS)
2001-04-01
The purpose of the Technical Committee Meeting (TCM) was to provide the opportunity to review the status of design and development activities associated with safety related and economic aspects of HTGRs, and to identify pathways which may provide the opportunity for international cooperation in addressing these issues. The HTGR, as a nuclear heat source for the safe, economic and efficient production of electricity and high temperature industrial processes has, within the past few years, become a significantly increasing influence in the future of nuclear power. Nuclear test facilities with the capability of achieving core outlet temperatures to 950 deg. C are presently under construction in China and Japan. These plants will be utilized to support HTGR research and development activities, including electricity generation via the gas turbine and validation of high temperature process heat applications. Also, major development programmes focusing on the generation of electricity through the direct cycle gas turbine are in progress by ESKOM, the state electric utility of South Africa, and by a consortium of organizations from the Russian Federation, USA, France and Japan. Other national programmes focusing on research and development of the HTGR are underway including the Netherlands, where an evaluation is being completed on a heat and power co-generation plant utilizing a small direct cycle HTR; in Germany, where the primary focus is centered on basic issues of reactor safety and innovative reactor technology; in Indonesia with the evaluation of process heat applications such as coal liquefaction, hydrogen production and high temperature reforming of methane; and in the USA with the recent re-introduction of national support for the HTGR specifically directed to the burning of weapons plutonium. The status information presented in several of the papers is as of the time of drafting. Thus other later material should be referenced for more current status information
PREFACE Surface Modifications of Diamond and Related Materials (Session D, E-MRS Spring Meeting)
Nebel, Christoph E.
2010-11-01
This special issue contains selected papers which were presented at the E-MRS Symposium BIOMATERIALS, SENSORS & SURFACES, D: 'Surface modifications of diamond and related materials' which was held on 7-9 June 2010 in Strasbourg (France). With about 54 oral and poster presentations given from teams all over the world it was a very interesting, dense and lively meeting. The symposium focused on chemical modifications applied to graft surfaces of diamond, nano-diamond particles, diamond-like carbon, graphene, graphite and carbon nano-tubes with linker molecular layers for realization of bio-sensors, bio-markers, separation techniques, and switchable chemical links. Presented techniques span spontaneous bonding to photo-chemical attachment, electrochemical modifications, to Suzuki-coupling of aryl molecules. Special attention was drawn to mechanisms driving bonding kinetics such as electron transfer reactions, hydrogen cleavage reactions by nucleophilic molecules and growths schemas which vary from correlated two-dimensional chain reactions to three-dimensional cross polymerization. Hydrogen terminations, surface defects, surface roughness and atomic arrangements of surface carbon atoms were of interest to elucidate bonding mechanisms. In addition, bonding stability, either of linker molecules or of complex functionalized surfaces with DNA, proteins and enzymes was discussed by several speakers as well as details of the electronic interfaces between solid transducers and bio-layers. Here the characterization of surface and interface defect densities, of Fermi level pinning and of electron transfer rates was a major topic. Miniaturization of sensor area and application of new detection schemas was discussed. Diamond nano-particles which are increasingly used as biomarkers in drug delivery experiments also attracted attention. The organizers express our gratitude to the international members of the scientific committee who actively contributed to ensure an attractive
Building the general relativity and gravitation community during the Cold War
Lalli, Roberto
2017-01-01
This monograph presents a new perspective on the history of general relativity. It outlines the attempts to establish an institutional framework for the promotion of the field during the Cold War. Readers will learn the difficulties that key figures experienced and overcame during this period of global conflict. The author analyzes the subtle interconnections between scientific and political factors. He shows how politics shaped the evolution of general relativity, even though it is a field with no military applications. He also details how different scientists held quite different views about what “political” meant in their efforts to pursue international cooperation. The narrative examines the specific epistemic features of general relativity that helped create the first official, international scientific society. It answers: Why did relativity bring about this unique result? Was it simply the product of specific actions of particular actors having an illuminated view of international relations in the...
Sutton, Patrick; Shoemaker, Deirdre
2009-06-01
The 2008 Numerical Relativity Data Analysis (NRDA) Meeting, the second in the series, was hosted by the Department of Physics at Syracuse University, 11-14 August 2008 with 60 participants. The purpose of the NRDA meetings is to bring together two communities with a vested interest in gravitational-wave observations: the data analysis and numerical relativity communities. The first NRDA meeting was held in November 2006 at MIT. A quote of Peter Saulson's from the Matters of Gravity Newsletter puts the importance of the NRDA meetings in perspective. He wrote: `As I sat in the back row of Rm NW14-1112 at MIT on Tuesday 7 November 2006, it suddenly struck me that we were participating in a watershed moment in the history of gravitational physics. Here, in the same room, were two communities who decades earlier had promised to help each other in a grand adventure: the detection of gravitational waves and the use of those waves to explore the frontiers of strong field gravity.' That meeting marked the first time when the two communities began to speak each other's language. By the time of the second NRDA meeting, much progress had been made. Numerical relativists were starting to explore the binary-black-hole parameter space and were making advances in evolutions of neutron-star and neutron-star/black-hole binaries. Data analysts were investigating better algorithms for the detection of both inspiral and burst sources. Most importantly, on 14 August 2008, someone sitting in the back row of the Stolkin Auditorium in Syracuse University might have noted the beginning of real collaborations between the two communities. The meeting included presentations based on joint work by numerical relativists and data analysts. Also the participants at NRDA2008 asked tough questions about how to best use numerical relativity in gravitational wave detection, as well as showcasing some of the science that will allow us to formulate the answers to these questions. This issue presents
Differences in social relations between persons with type 2 diabetes and the general population
DEFF Research Database (Denmark)
Hempler, Nana Folmann; Ekholm, Ola; Willaing, Ingrid
2013-01-01
with type 2 diabetes. The aim of this study was to investigate whether persons with type 2 diabetes have poorer social relations than the general population. Methods: We conducted a cross-sectional survey in three settings: a specialist diabetes clinic (SDC) (n = 1084), a web panel (WP) consisting...... of persons with type 2 diabetes (n = 1491) and a sample from the 2010 Danish Health and Morbidity Survey, representative of the general population (n = 15,165). We compared social relations using multivariate logistic regression. Results: Compared to the general population, persons with type 2 diabetes more.......41). Conclusions: Our findings suggest that persons with type 2 diabetes have poorer social relations than the general population. From a public health point of view, special attention is needed with regards to strengthening existing networks and establishing alternative networks among persons with type 2 diabetes....
Report of the IMFIT Advisory Committee from the Meeting of 9/16/08 at General Atomics
International Nuclear Information System (INIS)
Cohen, R.; Cary, J.; Houlberg, W.; McCune, D.
2008-01-01
The Committee commends and thanks the presenters and GA for providing clear and informative presentations. We present our responses to 5 questions raised in the Charge, as well as additional comments that may be useful for the project. (Question 1) The IMFIT framework is based on PYTHON and CCA; can IMFIT meet its long-term goals with this choice of language for framework? Our first recommendation is to change the terminology; it appears that the project is not really utilizing CCA (Common Component Architecture). The project is really about using Python to organize workflow among components that are spawned as processes via pipes from Python. We suggest that in describing the project, the team drop the designation 'CCA' and simply state that the IMFIT framework is based on using Python to control workflow among components. Concerning the specific question: we understand the principal goal of the project to be the development of an easy-to-use tool that efficiently integrates different physics modules to support experimental data analysis and modeling. Yes, Python and the workflow-based framework are appropriate choices for meeting this objective. The Committee, in examining the goal, discussed whether the IMFIT project was duplicative of other projects; there are several others in the U.S. and elsewhere with integrated modeling goals. In particular in the U.S., SWIM, PTRANSP, and the proto-FSP's. However this project occupies a reasonably unique niche through its emphases on integrating experimental data, use of existing components, its near-term focus, and the extent to which is targeted at experimentalist users. (Question 2) Will IMFIT benefit from the additional use of an interoperability language for framework such as BABEL? No, IMFIT is not really doing inter-language communication. In particular this will be the case as long as inter-component communication is via files--and that's OK so long as you aren't doing lots of short steps with communication at each
Report of the IMFIT Advisory Committee from the Meeting of 9/16/08 at General Atomics
Energy Technology Data Exchange (ETDEWEB)
Cohen, R; Cary, J; Houlberg, W; McCune, D
2008-10-22
The Committee commends and thanks the presenters and GA for providing clear and informative presentations. We present our responses to 5 questions raised in the Charge, as well as additional comments that may be useful for the project. (Question 1) The IMFIT framework is based on PYTHON and CCA; can IMFIT meet its long-term goals with this choice of language for framework? Our first recommendation is to change the terminology; it appears that the project is not really utilizing CCA (Common Component Architecture). The project is really about using Python to organize workflow among components that are spawned as processes via pipes from Python. We suggest that in describing the project, the team drop the designation 'CCA' and simply state that the IMFIT framework is based on using Python to control workflow among components. Concerning the specific question: we understand the principal goal of the project to be the development of an easy-to-use tool that efficiently integrates different physics modules to support experimental data analysis and modeling. Yes, Python and the workflow-based framework are appropriate choices for meeting this objective. The Committee, in examining the goal, discussed whether the IMFIT project was duplicative of other projects; there are several others in the U.S. and elsewhere with integrated modeling goals. In particular in the U.S., SWIM, PTRANSP, and the proto-FSP's. However this project occupies a reasonably unique niche through its emphases on integrating experimental data, use of existing components, its near-term focus, and the extent to which is targeted at experimentalist users. (Question 2) Will IMFIT benefit from the additional use of an interoperability language for framework such as BABEL? No, IMFIT is not really doing inter-language communication. In particular this will be the case as long as inter-component communication is via files--and that's OK so long as you aren't doing lots of short steps
Directory of Open Access Journals (Sweden)
Eivor Wiking
2013-01-01
Full Text Available Objective. In Sweden, about 19% of residents have a foreign background. Previous studies reported immigrant patients experience communication difficulties despite the presence of interpreters during consultations. The objective of this study was to gain insights into the participants’ perceptions and reflections of the triangular meeting by means of in-depth interviews with immigrant patients, interpreters, and general practitioners (GPs. Method. A total of 29 participants—10 patients, 9 interpreters, and 10 GPs—participated in face-to-face interviews. Content analysis was used to process the interview material. Results. Six themes were generated and arranged under two subject areas: the interpretation process (the means of interpreting and means of informing and the meeting itself (individual tailored approaches, consultation time, the patient’s feelings, and the role of family members. Conclusion. This paper highlights feelings including frustration and insecurity when interpretation and relationships are suboptimal. Strategies for immigrant patients, interpreters, and GPs for getting a successful consultation may be needed. To transform the triangular meeting from an encounter to a real meeting, our results indicate a need for professional interpreters, for GPs to use a patient-tailored approach, and sufficient consultation time. Practice Implications. Use of professional interpreters is recommended, as is developing cultural competence.
Hoffman, Eric W; Pinkleton, Bruce E; Weintraub Austin, Erica; Reyes-Velázquez, Wanda
2014-01-01
Alcohol marketers have increasingly moved their advertising efforts into digital and social media venues. As a result, the purpose of this study is to investigate associations between students' use of social media, their exposure to alcohol marketing messages through social media, and their alcohol-related beliefs and behaviors. Public and private university students (N = 637) participated November and December 2011 and April 2012. College students completed online surveys to measure their exposure to social and online media generally, as well as their alcohol-related digital media use and alcohol use. Use of social media related to alcohol marketing predicted alcohol consumption and engaging in risky behaviors, whereas the use of social media more generally did not. Students' use of alcohol-related social media-marketing content associates with their problem drinking. Results have implications for alcohol abuse reduction efforts targeted at college students and suggest the importance of considering social, cultural, and cognitive factors in campaign planning and design.
Energy Technology Data Exchange (ETDEWEB)
Ludyk, Guenter [Bremen Univ. (Germany). Physics and Electrical Engineering
2013-11-01
Derives the fundamental equations of Einstein's theory of special and general relativity using matrix calculus, without the help of tensors. Provides necessary mathematical tools in a user-friendly way, either directly in the text or in the appendices. Appendices contain an introduction to classical dynamics as a refresher of known fundamental physics. Rehearses vector and matrix calculus, differential geometry, and some special solutions of general relativity in the appendices. This book is an introduction to the theories of Special and General Relativity. The target audience are physicists, engineers and applied scientists who are looking for an understandable introduction to the topic - without too much new mathematics. The fundamental equations of Einsteins theory of Special and General Relativity are derived using matrix calculus, without the help of tensors. This feature makes the book special and a valuable tool for scientists and engineers with no experience in the field of tensor calculus. In part I the foundations of Special Relativity are developed, part II describes the structure and principle of General Relativity. Part III explains the Schwarzschild solution of spherical body gravity and examines the ''Black Hole'' phenomenon. Any necessary mathematical tools are user friendly provided, either directly in the text or in the appendices.
International Nuclear Information System (INIS)
Ludyk, Guenter
2013-01-01
Derives the fundamental equations of Einstein's theory of special and general relativity using matrix calculus, without the help of tensors. Provides necessary mathematical tools in a user-friendly way, either directly in the text or in the appendices. Appendices contain an introduction to classical dynamics as a refresher of known fundamental physics. Rehearses vector and matrix calculus, differential geometry, and some special solutions of general relativity in the appendices. This book is an introduction to the theories of Special and General Relativity. The target audience are physicists, engineers and applied scientists who are looking for an understandable introduction to the topic - without too much new mathematics. The fundamental equations of Einsteins theory of Special and General Relativity are derived using matrix calculus, without the help of tensors. This feature makes the book special and a valuable tool for scientists and engineers with no experience in the field of tensor calculus. In part I the foundations of Special Relativity are developed, part II describes the structure and principle of General Relativity. Part III explains the Schwarzschild solution of spherical body gravity and examines the ''Black Hole'' phenomenon. Any necessary mathematical tools are user friendly provided, either directly in the text or in the appendices.
47 CFR 73.1800 - General requirements related to the station log.
2010-10-01
... 47 Telecommunication 4 2010-10-01 2010-10-01 false General requirements related to the station log... requirements related to the station log. (a) The licensee of each station must maintain a station log as required by § 73.1820. This log shall be kept by station employees competent to do so, having actual...
Generalization of the Biot--Savart law to Maxwell's equations using special relativity
International Nuclear Information System (INIS)
Neuenschwander, D.E.; Turner, B.N.
1992-01-01
Maxwell's equations are obtained by generalizing the laws of magnetostatics, which follow from the Biot--Savart law and superposition, to be consistent with special relativity. The Lorentz force on a charged particle and its rate of energy change also follow by making Newton's second law for a particle in a magnetostatic field consistent with special relativity
Platsidou, Maria; Agaliotis, Ioannis
2017-01-01
The role of empathy in the teaching profession has been vastly investigated in relation to its effect on students, but research on how teachers' empathy affects their own well-being at work is limited. This study investigated empathy and instructional assignment-related stress factors of primary school teachers serving in general or special…
General dispersion and dissipation relations in a one-dimensional viscoelastic lattice
International Nuclear Information System (INIS)
Wang Wenqiang; Yu Jidong; Tang Zhiping
2008-01-01
We derive the general dispersion and dissipation relations for a one-dimensional viscoelastic lattice, demonstrate the relevance of these relations to viscoelastic fracture and phase transition, and show a procedure to determine the suitable mesh size in numerical simulation of stress waves propagating in viscoelastic continuum
Taylor, R; Ali, M H; Howe, T E; Varley, I
2017-07-01
Dually-registered specialists in oral and maxillofacial surgery (OMFS) may be subject to disciplinary hearings by the General Medical Council (GMC) and the General Dental Council (GDC) for the same allegations, a phenomenon referred to as "double jeopardy" within the specialty. Previous efforts by both councils to simplify regulatory arrangements have made little progress. We have therefore reviewed the range and scope of fitness to practise (FTP) proceedings relevant to OMFS. We searched the online GMC register to find registered OMFS specialists and obtained FTP proceedings from 2004-2016 through a Freedom of Information request from the GDC. We then searched for cases relevant to OMFS, and cross-checked GMC and GDC registers for dual registration before reviewing relevant cases and identifying and discussing themes. Seven OMFS specialists are currently subject to GMC sanctions. A total of 22 GDC hearings related to OMFS, all of which began after 2011. Six involved the practice of OMFS, work within an OMFS department, or work by a dually-registered doctor. While "double jeopardy" is uncommon, it does happen. The cases reviewed raise issues about the remit of the GDC and their understanding of clinical practice in OMFS. We found no evidence of progress in attempts to simplify FTP proceedings. The number of GDC hearings relevant to OMFS is increasing. Copyright © 2017 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Principles of general relativity theory in terms of the present day physics
International Nuclear Information System (INIS)
Pervushin, V.N.
1986-01-01
A hystory of gradual unification of general relativity theory and quantum field theory on the basis of unified geometrical principles is detected. The gauge invariance principles became universal for construction of all physical theories. Quantum mechanics, electrodynamics and Einstein gravitation theory were used to form geometrical principles. Identity of inertial and gravitational masses is an experimental basis of the general relativity theory (GRT). It is shown that correct understanding of GRT bases is a developing process related to the development of the present physics and stimulating this development
Ludyk, Günter
2013-01-01
This book is an introduction to the theories of Special and General Relativity. The target audience are physicists, engineers and applied scientists who are looking for an understandable introduction to the topic - without too much new mathematics. The fundamental equations of Einsteins theory of Special and General Relativity are derived using matrix calculus, without the help of tensors. This feature makes the book special and a valuable tool for scientists and engineers with no experience in the field of tensor calculus. In part I the foundations of Special Relativity are developed, part II describes the structure and principle of General Relativity. Part III explains the Schwarzschild solution of spherical body gravity and examines the "Black Hole" phenomenon. Any necessary mathematical tools are user friendly provided, either directly in the text or in the appendices.
European AIDS Clinical Society Standard of Care meeting on HIV and related coinfections
DEFF Research Database (Denmark)
Mussini, C; Antinori, A; Bhagani, S
2016-01-01
OBJECTIVES: The objective of the 1st European AIDS Clinical Society meeting on Standard of Care in Europe was to raise awareness of the European scenario and come to an agreement on actions that could be taken in the future. METHODS: Data-driven presentations were given on specific topics followed...... by interactive panel discussions. RESULTS: In Eastern European countries, the epidemic is largely driven by injecting drug use, in contrast with Western Europe where the infection mainly occurs through heterosexual contact. A high proportion of people living with HIV remain unaware of their infection...... diagnosed multi-drug-resistant cases. Hepatitis C is widespread in selected geographical areas and risk groups. CONCLUSIONS: The key conclusion from the meeting was that a high-priority group of actions could be identified, including: increasing HIV awareness and testing, improving training for health care...
Weingarden, Hilary; Renshaw, Keith D; Davidson, Eliza; Wilhelm, Sabine
2017-07-01
Body Dysmorphic Disorder (BDD) is characterized by a preoccupation with a perceived flaw in appearance and repetitive avoidance behaviors. BDD involves severe psychosocial outcomes (e.g., depression, suicidality, functional impairment). Identifying correlates of BDD symptoms and outcomes can inform treatment. Shame, a painful emotion felt in response to critical self-judgment, may be one key correlate. However, research on shame in BDD is scarce and previous studies have not distinguished general shame from body shame. This study examines the relative relationships between body shame and general shame with body dysmorphic phenomenology and psychosocial outcomes. Participants ( N = 184) were recruited online via BDD organizations and completed a survey. Path analysis was used to examine associations between body and general shame with 1) body dysmorphic phenomenology and 2) depression severity, suicide risk, and functional impairment. Both types of shame were differentially related to outcomes. Body shame was more strongly related to phenomenology, whereas general shame was more strongly related to psychosocial outcomes. Thus, it may be important for BDD treatment to focus on reducing both general and body shame. Further research should evaluate whether current treatments adequately address and reduce general and body shame, and whether addressing shame promotes better treatment outcomes.
International Nuclear Information System (INIS)
Hikima, Akio; Mochizuki, Hiroyuki; Oriuchi, Noboru; Endo, Keigo; Morikawa, Akihiro
2004-01-01
Positron emission tomography (PET) with [ 18 F]fluoro-D-deoxyglucose (FDG) has been used to detect seizure foci and evaluate surgical resection with localization related epilepsies. However, few investigations have focused on generalized epilepsy in children. To reveal the pathophysiology of generalized epilepsy, we studied 11 patients with generalized epilepsy except West syndrome, and 11 patients with localization related epilepsy without organic disease. The FDG PET was performed by simultaneous emission and transmission scanning. We placed regions of interest (ROI) on bilateral frontal lobe, parietal lobe, occipital lobe, temporal lobe, basal ganglia, thalamus and cerebellum. Standardized uptake value (SUV) was measured and normalized to SUV of ipsilateral cerebellum. Then, we compared the data of generalized epilepsy to those of localization related epilepsy. FDG PET revealed significant interictal glucose hypometabolism in bilateral basal ganglia in generalized epilepsy compared to that in localization related epilepsy (right side: p=0.0095, left side: p=0.0256, Mann-Whitney test). No other region showed any significant difference (p>0.05) between the two groups. These findings indicate that the basal ganglia is involved in the outbreak of generalized seizures or is affected secondarily by the epileptogenicity itself. (author)
van Dongen, Jeroen
2011-01-01
Two important and unpleasant events occurred in Albert Einstein’s life in 1920: That August an antirelativity rally was held in the large auditorium of the Berlin Philharmonic, and a few weeks later Einstein was drawn into a tense and highly publicized debate with Philipp Lenard on the merits of relativity at a meeting in Bad Nauheim, Germany. I review these events and discuss how they affected Einstein in light of new documentary evidence that has become available through the publication of ...
[NCRP comments on radiation protection related reports, proposed standards, and meetings
International Nuclear Information System (INIS)
1991-01-01
Two NCRP Reports, two Annual Meeting Proceedings and one Commentary have been published during this period. NCRP Report No. 105, Radiation Protection for Medical and Allied Health Personnel is a rewrite and update of NCRP Report No. 48, which had the same title and which it supersedes. The primary objective of the new report is to update the material to include new radiation sources used in medicine. NCRP Report No. 106, Limit for Exposure to ''Hot Particles'' on the Skin was prepared in response to a request from the Nuclear Regulatory Commission. The report addresses the potential biological effect of microscopic radioactive particles on the skin and reviews the presently available information on the subject. Proceedings No. 10, Radon, is the proceedings of the 24th Annual Meeting of the NCRP. Proceedings No. 11, Radiation Protection Today---The NCRP at Sixty Years is the proceedings of the 25th Annual Meeting of the NCRP. Commentary No. 5, Review of the Publication, Living Without Landfills, was recently released. Also included is a list of NCRP committee reports which were released in the current reporting period
The roles of general and technology-related parenting in managing youth screen time.
Sanders, Wesley; Parent, Justin; Forehand, Rex; Breslend, Nicole Lafko
2016-08-01
This study examines the associations of 2 types of parenting practices-general adaptive parenting and technology-related strategies-with youth screen time. We hypothesized that technology-related parenting focused on behavioral control would relate directly to screen time and serve to link general parenting to screen time. Participants were 615 parents drawn from 3 community samples of families with children across 3 development stages: young childhood (3-7 years; n = 210), middle childhood (8-12 years; n = 200), and adolescents (13-17 years; n = 205). Using structural equation modeling, we found that general adaptive parenting was not related to child screen time but was positively related to technology-related parenting strategies for all 3 samples. For the young and, to some extent, middle childhood samples, but not for the adolescent sample, general adaptive parenting was positively linked to youth screen time through technology-related parenting strategies. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
International Nuclear Information System (INIS)
2009-01-01
This conference was attended by experts on current issues in engineering of an urban ecosystem, composting, biofuels and green energy. The meeting provided a forum to discuss advances in the application of engineering principles and practices dealing with biological systems for the production of food, bioproducts and energy. The discussions focused on engineering practices in agriculture, forestry, bioresources, biochemistry and biosystems. The 7 technical sessions of the conference were entitled: aquaculture; safety and training; bioprocessing; energy production and biofuels; environment and ecology; soil and water; and development of technologies. The conference feature 58 presentations, of which 9 have been catalogued separately for inclusion in this database. refs., tabs., figs
Campanelli, M.; Rezzolla, L.
2007-06-01
techniques and the mathematical methods needed for successful solution of the Einstein equations for binary black holes. Clearly, an important frontier, and actually a long-awaited one, was finally open and the `gold rush' was just about to begin by the time the `New Frontiers in Numerical Relativity' meeting started its sessions in July 2006. And so, almost 20 years since the almost homonymous meeting held at Urbana Champaign (`Frontiers in Numerical Relativity', University of Illinois, IL, USA, 1988), the `New Frontiers in Numerical Relativity' meeting at the AEI saw the enthusiastic participation of a great part of the community, with 127 participants present (in 1988 they were 55) and with a large majority being represented by students and postdocs, a reassuring sign of good health for the community. Faithful to the title of the conference, the programme was dedicated to the many and diversified `frontiers' in numerical relativity and organized so as to have few talks with ample time dedicated to discussions. Overall, the talks presented at the meeting covered all of the most salient aspects of numerical relativity: from the formulation of the Einstein equations, over to the initial-value problem in general relativity, from the evolution of vacuum and non-vacuum spacetimes, to multiblock adaptive mesh-refinement techniques, from boundary conditions and perturbative methods, to relativistic fluids and plasmas. The contributions in this special issue represent a selection of that research, but also include invited papers from authors who were not present at the meeting but were pursuing research at the forefronts of numerical relativity. In addition to the more traditional sessions, the `New Frontiers in Numerical Relativity' meeting also hosted a less traditional session, dedicated to an `unconstrained' discussion which covered some of the most controversial issues that emerged during the conference. During this session, chaired by E Seidel, a lively discussion took place
General tradeoff relations of quantum nonlocality in the Clauser–Horne–Shimony–Holt scenario
Energy Technology Data Exchange (ETDEWEB)
Su, Hong-Yi, E-mail: hongyisu@chonnam.ac.kr [Department of Physics Education, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Chen, Jing-Ling [Theoretical Physics Division, Chern Institute of Mathematics, Nankai University, Tianjin 300071 (China); Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543 (Singapore); Hwang, Won-Young, E-mail: wyhwang@jnu.ac.kr [Department of Physics Education, Chonnam National University, Gwangju 500-757 (Korea, Republic of)
2017-02-15
General tradeoff relations present in nonlocal correlations of bipartite systems are studied, regardless of any specific quantum states and measuring directions. Extensions to multipartite scenarios are possible and very promising. Tsirelson’s bound can be derived out in particular. The close connection with uncertainty relations is also presented and discussed. - Highlights: • Quantum violation of CHSH inequalities is found to satisfy tradeoff relations. • Tsirelson’s bound for quantum mechanics can be directly implied from these tradeoffs. • Tradeoff relations shed new light on uncertainty relations in summation forms.
A Broader View of Relativity General Implications of Lorentz and Poincaré Invariance
Hsu, Jong-Ping
2006-01-01
A Broader View of Relativity shows that there is still new life in old physics. The book examines the historical context and theoretical underpinnings of Einstein's theory of special relativity and describes Broad Relativity, a generalized theory of coordinate transformations between inertial reference frames that includes Einstein's special relativity as a special case. It shows how the principle of relativity is compatible with multiple concepts of physical time and how these different procedures for clock synchronization can be useful for thinking about different physical problems, includin
78 FR 60866 - National Coal Council Meeting
2013-10-02
...: Washington Court Hotel, 525 New Jersey Avenue NW., Washington, DC 20001-1527. FOR FURTHER INFORMATION CONTACT... general policy matters relating to coal and the coal industry Purpose of Meeting: The November 2013...
International Nuclear Information System (INIS)
Altac, Zekeriya
2007-01-01
Generalized exponential integral functions (GEIF) are encountered in multi-dimensional thermal radiative transfer problems in the integral equation kernels. Several series expansions for the first-order generalized exponential integral function, along with a series expansion for the general nth order GEIF, are derived. The convergence issues of these series expansions are investigated numerically as well as theoretically, and a recurrence relation which does not require derivatives of the GEIF is developed. The exact series expansions of the two dimensional cylindrical and/or two-dimensional planar integral kernels as well as their spatial moments have been explicitly derived and compared with numerical values
Longitudinal Relation Between General Well-Being and Self-Esteem.
Barendregt, Charlotte S; van der Laan, André M; Bongers, Ilja L; van Nieuwenhuizen, Chijs
2016-12-01
This study investigated the longitudinal relation between general well-being and self-esteem of male adolescents with severe psychiatric disorders. Moreover, the transition out of secure residential care was studied. Adolescents ( N = 172) were assessed three times with 6 months between each assessment. The sample comprised adolescents who were admitted throughout the entire study ( n = 116) and who had been discharged at 6/12 months follow-up ( n = 56). General well-being and self-esteem were stable concepts over time. The relation between general well-being and self-esteem differed for both groups. Among the admitted group general well-being positively predicted self-esteem and self-esteem negatively predicted general well-being from Time 2 to Time 3. Among the discharged adolescents, self-esteem at Time 1 positively predicted general well-being at Time 2 and general well-being at Time 2 positively predicted self-esteem at Time 3. Changing social contexts, as well as problems experienced during the transition out of secure care, might affect this relationship.
The basis of general practice, its content and relation to training.
Levenstein, J H
1977-08-13
The present status is the newly defined discipline of general practice is briefly outlined. The reasons for its worldwide upsurge in the past decade and the relative failure of South Africa to keep abreast are reviewed. A brief exposition is given of the knowledge and skills required for general practice, the consultation, the clinical process and the content of what in some countries is regarded as family medicine. The difference in ethos between 'doctor-orientated' and 'patient-orientated' medicine is discussed. The latter approach is essential to general practice, in which the attidudes of both doctor and patient and their interactions are known to have an effect on the clinical process. The non-directive educative approach is discussed in relation to undergraduate and postgraduate training, and the attempts to make postgraduate general practice examinations valid and reliable, so that they evaluate the actual day-to-day activities of the doctor, are alluded to. The content of general practice is as yet not clearly identified and the problems encountered in delineating these as well as suggested approaches are presented. It is concluded that in South Africa no serious attempts have been made by legislative bodies and most medical educational institutions to recognize general practice as a new displine in spite of pioneering work achieved by the Faculty of General Practice of the College of Medicine of South Africa.
Gralla, Samuel E.; Lupsasca, Alexandru; Philippov, Alexander
2017-12-01
In the canonical model of a pulsar, rotational energy is transmitted through the surrounding plasma via two electrical circuits, each connecting to the star over a small region known as a “polar cap.” For a dipole-magnetized star, the polar caps coincide with the magnetic poles (hence the name), but in general, they can occur at any place and take any shape. In light of their crucial importance to most models of pulsar emission (from radio to X-ray to wind), we develop a general technique for determining polar cap properties. We consider a perfectly conducting star surrounded by a force-free magnetosphere and include the effects of general relativity. Using a combined numerical-analytical technique that leverages the rotation rate as a small parameter, we derive a general analytic formula for the polar cap shape and charge-current distribution as a function of the stellar mass, radius, rotation rate, moment of inertia, and magnetic field. We present results for dipole and quadrudipole fields (superposed dipole and quadrupole) inclined relative to the axis of rotation. The inclined dipole polar cap results are the first to include general relativity, and they confirm its essential role in the pulsar problem. The quadrudipole pulsar illustrates the phenomenon of thin annular polar caps. More generally, our method lays a foundation for detailed modeling of pulsar emission with realistic magnetic fields.
Generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture.
Felderhof, B U
2017-08-21
The method employed by Einstein to derive his famous relation between the diffusion coefficient and the friction coefficient of a Brownian particle is used to derive a generalized Einstein relation for the mutual diffusion coefficient of a binary fluid mixture. The expression is compared with the one derived by de Groot and Mazur from irreversible thermodynamics and later by Batchelor for a Brownian suspension. A different result was derived by several other workers in irreversible thermodynamics. For a nearly incompressible solution, the generalized Einstein relation agrees with the expression derived by de Groot and Mazur. The two expressions also agree to first order in solute density. For a Brownian suspension, the result derived from the generalized Smoluchowski equation agrees with both expressions.
Directory of Open Access Journals (Sweden)
Maryam A. Alghamdi
2014-01-01
Full Text Available We introduce the notion of generalized weaker (α-ϕ-φ-contractive mappings in the context of generalized metric space. We investigate the existence and uniqueness of fixed point of such mappings. Some consequences on existing fixed point theorems are also derived. The presented results generalize, unify, and improve several results in the literature.
The Theological Basis of Big Bang Cosmology and the Failure of General Relativity
Crothers, Stephen J.
2013-09-01
It is shown in this paper that the Big Bang Cosmology has its basis in theology, not in science, that it pertains to a Universe entirely filled by a single spherically symmetric continuous indivisible homogeneous body and therefore models nothing, that it violates the physical principles of General Relativity, that it violates the conservation of energy, and that General Relativity itself violates the usual conservation of energy and momentum and is therefore in conflict with experiment on a deep level, rendering Einstein's conception of the physical Universe and the gravitational field invalid.