Dirac Equation in Gauge and Affine-Metric Gravitation Theories
Giachetta, G.; Sardanashvily, G.
1995-01-01
We show that the covariant derivative of Dirac fermion fields in the presence of a general linear connection on a world manifold is universal for Einstein's, gauge and affine-metric gravitation theories.
Smith, Peter D
2003-01-01
Albert Einstein re-wrote the textbooks of science in 1905: physics since has been little more than a series of footnotes to the theories of a 26-year-old patent-office clerk. Einstein's science and emotional life come together in this vivid portrait of a rebellious and contradictory figure, a pacifist whose legendary equation E=mc2 opened scientists' eyes to the terrible power within every atom. 'To punish me for my contempt for authority,' he lamented, 'Fate has made me an authority myself.'
A Discontinuous Galerkin Method Compatible with the BSSN Formulation of the Einstein Equations
Miller, Jonah; Schnetter, Erik
2017-01-01
The BSSN formulation of the Einstein equations has repeatedly demonstrated its robustness. The formulation is not only stable but allows for puncture-type evolutions of black hole systems. Discontinuous Galerkin Finite Element (DGFE) methods offer a mathematically beautiful, computationally efficient, and highly parallelizable way to solve hyperbolic PDEs. These properties make them highly desirable for numerical relativity. To-date no one has been able to solve the full (3+1)-dimensional BSSN equations using DGFE methods. This is partly because DGFE discretization often occurs at the level of the equations, not the derivative operator, and partly because DGFE methods are traditionally formulated for manifestly flux-conservative systems. By discretizing the derivative operator, we generalize a particular flavor of DGFE methods, Local DG methods, to solve arbitrary second-order hyperbolic equations. This generalization allows us to solve the BSSN equations. The authors acknowledge support from the Natural Sciences and Engineering Research Council of Canada and from the National Science Foundation of the USA (OCI 0905046, PHY 1212401).
Mansuripur, Masud
2015-01-01
The classical theory of electrodynamics cannot explain the existence and structure of electric and magnetic dipoles, yet it incorporates such dipoles into its fundamental equations, simply by postulating their existence and properties, just as it postulates the existence and properties of electric charges and currents. Maxwell's macroscopic equations are mathematically exact and self-consistent differential equations that relate the electromagnetic (EM) field to its sources, namely, electric charge-density 𝜌𝜌free, electric current-density 𝑱𝑱free, polarization 𝑷𝑷, and magnetization 𝑴𝑴. At the level of Maxwell's macroscopic equations, there is no need for models of electric and magnetic dipoles. For example, whether a magnetic dipole is an Amperian current-loop or a Gilbertian pair of north and south magnetic monopoles has no effect on the solution of Maxwell's equations. Electromagnetic fields carry energy as well as linear and angular momenta, which they can exchange with material media—the seat of the sources of the EM field—thereby exerting force and torque on these media. In the Lorentz formulation of classical electrodynamics, the electric and magnetic fields, 𝑬𝑬 and 𝑩𝑩, exert forces and torques on electric charge and current distributions. An electric dipole is then modeled as a pair of electric charges on a stick (or spring), and a magnetic dipole is modeled as an Amperian current loop, so that the Lorentz force law can be applied to the corresponding (bound) charges and (bound) currents of these dipoles. In contrast, the Einstein-Laub formulation circumvents the need for specific models of the dipoles by simply providing a recipe for calculating the force- and torque-densities exerted by the 𝑬𝑬 and 𝑯𝑯 fields on charge, current, polarization and magnetization. The two formulations, while similar in many respects, have significant
Interacting multiple zero mode formulation for a dark soliton in a Bose-Einstein condensate
Takahashi, Junichi; Nakamura, Yusuke; Yamanaka, Yoshiya
The system of Bose-Einstein condensate (BEC) has a zero-mode (ZM) associated with the spontaneous breakdown of the global phase symmetry. However, to formulate the ZMs in quantum field theory for a finite-size system with spontaneous breakdown of symmetries is not trivial, for in the naive Bogoliubov theory one encounters difficulties such as phase diffusion, the absence of a definite criterion for determining the ground state, and infrared divergences. In order to remove this difficulty, we have recently proposed the new treatment of the ZM, which enable us to introduce a unique ground state in the ZM sector. Using this ground state, we have evaluated the quantum fluctuation for the phase of condensate. In this presentation, we consider an atomic BEC system with a dark soliton that contains two ZMs corresponding to spontaneous breakdown of the global phase and translational symmetries. In our treatment, the original non-liner interaction of the field operator brings us the interaction between the two ZMs. We evaluate the standard deviations of the ZM operators and see how the mutual interaction between the two ZMs affects them.
Continuum interpretation of the dynamical-triangulation formulation of quantum Einstein gravity
Smit, Jan
2013-01-01
In the time-space symmetric version of dynamical triangulation, a non-perturbative version of quantum Einstein gravity, numerical simulations without matter have shown two phases, with spacetimes that are either crumpled or elongated like branched polymers, with strong evidence of a first-order transition between them. These properties have generally been considered unphysical. Using previously unpublished numerical results, we give an interpretation in terms of continuum spacetimes that have constant positive an negative curvature, respectively in the 'elongated' and 'crumpled' phase. The magnitude of the positive curvature leads naturally to average spacetimes consisting solely of baby-universes in a branched-polymer structure, whereas the negative curvature accommodates easily a large mother universe, albeit with a crumpling singularity. Nevertheless, there is evidence for scaling in the crumpled phase, which we compare with the well-known scaling in the elongated phase. Using constraint effective-action m...
Numerical stability of a new conformal-traceless 3 + 1 formulation of the Einstein equation
Laguna, P
2002-01-01
There is strong evidence indicating that the particular form used to recast the Einstein equation as a 3 + 1 set of evolution equations has a fundamental impact on the stability properties of numerical evolutions involving black holes and/or neutron stars. Presently, the longest lived evolutions have been obtained using a parametrized hyperbolic system developed by Kidder, Scheel and Teukolsky or a conformal-traceless system introduced by Baumgarte, Shapiro, Shibata and Nakamura. We present a new conformal-traceless system. While this new system has some elements in common with the Baumgarte-Shapiro-Shibata-Nakamura system, it differs in both the type of conformal transformations and how the nonlinear terms involving the extrinsic curvature are handled. We show results from 3D numerical evolutions of a single, non-rotating black hole in which we demonstrate that this new system yields a significant improvement in the lifetime of the simulations.
Directory of Open Access Journals (Sweden)
Yansheng Li
2016-08-01
Full Text Available With the urgent demand for automatic management of large numbers of high-resolution remote sensing images, content-based high-resolution remote sensing image retrieval (CB-HRRS-IR has attracted much research interest. Accordingly, this paper proposes a novel high-resolution remote sensing image retrieval approach via multiple feature representation and collaborative affinity metric fusion (IRMFRCAMF. In IRMFRCAMF, we design four unsupervised convolutional neural networks with different layers to generate four types of unsupervised features from the fine level to the coarse level. In addition to these four types of unsupervised features, we also implement four traditional feature descriptors, including local binary pattern (LBP, gray level co-occurrence (GLCM, maximal response 8 (MR8, and scale-invariant feature transform (SIFT. In order to fully incorporate the complementary information among multiple features of one image and the mutual information across auxiliary images in the image dataset, this paper advocates collaborative affinity metric fusion to measure the similarity between images. The performance evaluation of high-resolution remote sensing image retrieval is implemented on two public datasets, the UC Merced (UCM dataset and the Wuhan University (WH dataset. Large numbers of experiments show that our proposed IRMFRCAMF can significantly outperform the state-of-the-art approaches.
Directory of Open Access Journals (Sweden)
Dirk van Delft
2016-10-01
Full Text Available Einstein’s Holland Circle. Introduction.While he was formulating his General Theory of Relativity and working out its implications, Einstein liked to test his ideas against the accumulated experience of Dutch colleagues. As an offspring of the exhibition ‘Einstein & Friends’ in Museum Boerhaave, we present a collection of essays about Einstein’s contacts in the Netherlands.
Einstein: A Historical Perspective
Kormos-Buchwald, Diana
2015-04-01
In late 1915, Albert Einstein (1879-1955) completed as series of papers on a generalized theory of gravitation that were to constitute a major conceptual change in the history of modern physics and the crowning achievement of his scientific career. But this accomplishment came after a decade of intense intellectual struggle and was received with muted enthusiasm. Einstein's previously unpublished writings and massive correspondence, edited by the Einstein Papers Project, provide vivid insights into the historical, personal, and scientific context of the formulation, completion, and reception of GR during the first decades of the 20th century.
Weisskopf,V; Fubini,S; Berob
1979-01-01
Commémoration de A.Einstein avec 4 orateurs pour honnorer sa mémoire: le prof.Weisskopf parlera de l'homme de science engagé, Daniel Amati du climat de la physique aux années 1920, Sergio Fubini de l'heure scientifique d'A.Einstein et le prof.Berob(?)
Shapiro Key, Joey; Yunes, Nicolas
2013-04-01
The Gravity Group at Montana State University (MSU) hosted Celebrating Einstein, a free public arts and multimedia event celebrating Einstein and his ideas in Bozeman, Montana April 2-6, 2013. The products of our efforts are now available to any party interested in hosting a similar event. Celebrating Einstein is a truly interdisciplinary effort including art, film, dance, music, physics, history, and education. Events included a black hole immersive art installation, a series of public talks by physicists, and Einstein lessons in the public schools leading up to a live free public multimedia performance including a professional dance company, a live interview with a renowned physicist, and an original score composed for the MSU student symphony to be performed with an original film produced by the Science and Natural History film program at MSU. This project is funded by the Montana Space Grant Consortium, Montana State University, and the National Science Foundation.
Directory of Open Access Journals (Sweden)
Le Comité de Rédaction d' EspacesTemps.net
2004-09-01
Full Text Available Vous découvrez aujourd’hui la nouvelle formule d’EspacesTemps. net. Ce basculement repose sur des changements techniques d’une certaine ampleur et nous vous demandons d’être indulgents si quelques imperfections subsistent dans les prochains jours. Il s’agit d’abord de la substitution du dispositif de mise en ligne : à partir de maintenant, nous utilisons le logiciel Lodel. Dans l’esprit de l’association Revues.org, à laquelle EspacesTemps adhère, l’unification du ...
Gjurchinovski, Aleksandar; Skeparovski, Aleksandar
2008-01-01
Reflection of light from a plane mirror in uniform rectilinear motion is a century-old problem, intimately related to the foundations of special relativity. The problem was first investigated by Einstein in his famous 1905 paper by using the Lorentz transformations to switch from the mirror's rest frame to the frame where the mirror moves at a…
Hertz, P.
2003-03-01
The Structure and Evolution of the Universe (SEU) theme within NASA's Office of Space Science seeks to explore and understand the dynamic transformations of energy in the Universe - the entire web of biological and physical interactions that determine the evolution of our cosmic habitat. This search for understanding will enrich the human spirit and inspire a new generation of explorers, scientists, and engineers. To that end, NASA's strategic planning process has generated a new Roadmap to enable those goals. Called "Beyond Einstein", this Roadmap identifies three science objectives for the SEU theme: (1) Find out what powered the Big Bang; (2) Observe how black holes manipulate space, time, and matter; and (3) Identify the mysterious dark energy pullingthe Universe apart. These objectives can be realized through a combination of large observatories (Constellation-X, LISA), moderate sized, PI-led missions (the Einstein Probes), and a contuinuing program of technology development, research and analysis, and education/public outreach. In this presentation, NASA's proposed Beyond Einstein Program will be described. The full Roadmap is available at http://universe.nasa.gov/.
Petrov, Aleksej Z
1969-01-01
Einstein Spaces presents the mathematical basis of the theory of gravitation and discusses the various spaces that form the basis of the theory of relativity. This book examines the contemporary development of the theory of relativity, leading to the study of such problems as gravitational radiation, the interaction of fields, and the behavior of elementary particles in a gravitational field. Organized into nine chapters, this book starts with an overview of the principles of the special theory of relativity, with emphasis on the mathematical aspects. This text then discusses the need for a ge
Miller, Arthur I.
2004-11-01
How the 20th century’s most important scientist—Albert Einstein—and its most important artist—Pablo Picasso—made their greatest discoveries at almost the same time is a remarkable story: Einstein's relativity theory in 1905 and Picasso's Les Demoiselles d'Avignon two years later. A scientist and an artist confronted the same problem—the nature of time and simultaneity—and resolved it after realizing a new aesthetic. At the nascent moment of creativity boundaries dissolve between disciplines. This article explores the similarities in the early work of two of the greatest icons of Art and Science of the last century.
Schwinger's Approach to Einstein's Gravity
Milton, Kim
2012-05-01
Albert Einstein was one of Julian Schwinger's heroes, and Schwinger was greatly honored when he received the first Einstein Prize (together with Kurt Godel) for his work on quantum electrodynamics. Schwinger contributed greatly to the development of a quantum version of gravitational theory, and his work led directly to the important work of (his students) Arnowitt, Deser, and DeWitt on the subject. Later in the 1960's and 1970's Schwinger developed a new formulation of quantum field theory, which he dubbed Source Theory, in an attempt to get closer contact to phenomena. In this formulation, he revisited gravity, and in books and papers showed how Einstein's theory of General Relativity emerged naturally from one physical assumption: that the carrier of the gravitational force is a massless, helicity-2 particle, the graviton. (There has been a minor dispute whether gravitational theory can be considered as the massless limit of a massive spin-2 theory; Schwinger believed that was the case, while Van Dam and Veltman concluded the opposite.) In the process, he showed how all of the tests of General Relativity could be explained simply, without using the full machinery of the theory and without the extraneous concept of curved space, including such effects as geodetic precession and the Lense-Thirring effect. (These effects have now been verified by the Gravity Probe B experiment.) This did not mean that he did not accept Einstein's equations, and in his book and full article on the subject, he showed how those emerge essentially uniquely from the assumption of the graviton. So to speak of Schwinger versus Einstein is misleading, although it is true that Schwinger saw no necessity to talk of curved spacetime. In this talk I will lay out Schwinger's approach, and the connection to Einstein's theory.
Einstein's Phobia of Philosophy
Martinez, Alberto
The famous philosopher Henri Bergson criticized Einstein's special theory of relativity by imagining giants, microbes, two-dimensional beings, and a ''supreme consciousness.'' He argued that Einstein had arbitrarily made a sharp distinction between local and distant events and that Einstein confused time itself with mere clock measurements. I will discuss why Einstein dodged Bergson's pushy efforts to inject more subjectivity into relativity theory by explaining how Einstein, as a lonely young man, developed his critical views on philosophy. This talk is part of the invited FHP session on The Physicist and the Philosopher: Einstein, Bergson and the Debate that Changed Our Understanding of Time.
Wang, McKenzie
1999-01-01
This is the sixth volume in a series providing surveys of differential geometry. It addresses: Einstein manifolds with zero Ricci curvature; rigidity and compactness of Einstein metrics; general relativity; the stability of Minkowski space-time; and more.
Indian Academy of Sciences (India)
Einstein's Life and Legacy. Introduction. Albert Einstein is the most luminous scientist of the past century, and ranks with Isaac. Newton as one among the greatest physicists of all time. There is an enormous amount of material to choose from in talking about Einstein. He is without doubt also the most written about scientist of ...
Hess, Karl
2014-01-01
All modern books on Einstein emphasize the genius of his relativity theory and the corresponding corrections and extensions of the ancient space-time concept. However, Einstein's opposition to the use of probability in the laws of nature and particularly in the laws of quantum mechanics is criticized and often portrayed as outdated. The author of Einstein Was Right! takes a unique view and shows that Einstein created a ""Trojan horse"" ready to unleash forces against the use of probability as a basis for the laws of nature. Einstein warned that the use of probability would, in the final analys
Einstein solvmanifolds and the pre-Einstein derivation
Nikolayevsky, Y.
2008-01-01
An Einstein nilradical is a nilpotent Lie algebra, which can be the nilradical of a metric Einstein solvable Lie algebra. The classification of Riemannian Einstein solvmanifolds (possibly, of all noncompact homogeneous Einstein spaces) can be reduced to determining, which nilpotent Lie algebras are Einstein nilradicals and to finding, for every Einstein nilradical, its Einstein metric solvable extension. For every nilpotent Lie algebra, we construct an (essentially unique) derivation, the pre...
Einstein and the Special Theory of Relativity
Indian Academy of Sciences (India)
Even Poincare who came very close to formulating a principle of relativity was handicapped by the popular bias of retaining the ether. Einstein, being far removed from the mainstream, approached the problem differently. He made a small number of general postulates and built his theory on them. In contrast, Lorentz made a.
The ultimate quotable Einstein
2011-01-01
Here is the definitive new edition of the hugely popular collection of Einstein quotations that has sold tens of thousands of copies worldwide and been translated into twenty-five languages. The Ultimate Quotable Einstein features 400 additional quotes, bringing the total to roughly 1,600 in all. This ultimate edition includes new sections--"On and to Children," "On Race and Prejudice," and "Einstein's Verses: A Small Selection"--as well as a chronology of Einstein's life and accomplishments, Freeman Dyson's authoritative foreword, and new commentary by Alice Calaprice.
Einstein's equations from Einstein's inertial motion and Newton's law for relative acceleration
Schmid, Christoph
2016-01-01
We show that Einstein's $R^{\\hat{0} \\hat{0}}$ equation for nonrelativistic matter and strong gravitational fields is identical with Newton's equation for relative radial acceleration of neighbouring freefalling particles, spherically averaged. These laws are explicitely identical with primary observer's (1) space-time slicing by radial 4-geodesics, (2) radially parallel Local Ortho-Normal Bases, LONBs, (3) Riemann normal 3-coordinates. Hats on indices denote LONBs. General relativity follows from Newton's law of relative acceleration, Einstein's inertial motion, Lorentz covariance, and energy-momentum conservation combined with Bianchi identity. The gravitational field equation of Newton-Gauss and Einstein's $R^{\\hat{0} \\hat{0}}$ equation are identical and linear in gravitational field for an inertial primary observer.--- Einstein's equivalence between fictitious forces and gravitational forces is formulated as equivalence theorem in the equations of motion. With this, the gravitational field equation of 19th...
Science Scope, 2006
2006-01-01
This article deals with a pale blue sculpture entitled "A New World View", as an homage to the most famous scientist in modern history, Albert Einstein. It has 32 bas-relief squares composed of glass and steel that represent one aspect of the life and legacy of Albert Einstein. Images of children's faces peer out from behind the glass squares,…
Dieks, D.G.B.J.
In het jaar 1905 publiceerde Albert Einstein een reeks artikelen die een omwenteling voor de wetenschap betekende. En toch bleef Einstein een kind van zijn tijd, van een eeuw die in het teken stond van dynamo’s, raderen en stoommachines.
On Certain Conceptual Anomalies in Einstein's Theory of Relativity
Directory of Open Access Journals (Sweden)
Crothers S. J.
2008-01-01
Full Text Available There are a number of conceptual anomalies occurring in the Standard exposition of Einstein's Theory of Relativity. These anomalies relate to issues in both mathematics and in physics and penetrate to the very heart of Einstein's theory. This paper reveals and amplifies a few such anomalies, including the fact that Einstein's field equations for the so-called static vacuum configuration, $R_{mu u} = 0$, violates his Principle of Equivalence, and is therefore erroneous. This has a direct bearing on the usual concept of conservation of energy for the gravitational field and the conventional formulation for localisation of energy using Einstein's pseudo-tensor. Misconceptions as to the relationship between Minkowski spacetime and Special Relativity are also discussed, along with their relationships to the pseudo-Riemannian metric manifold of Einstein's gravitational field, and their fundamental geometric structures pertaining to spherical symmetry.
Heilbron, John
2005-03-01
As an editor of the Annalen der Physik, Max Planck published Einstein's early papers on thermodynamics and on special relativity, which Planck probably was the first major physicist to appreciate. They respected one another not only as physicists but also, for their inspired creation of world pictures, as artists. Planck helped to establish Einstein in a sinecure at the center of German physics, Berlin. Despite their differences in scientific style, social life, politics, and religion, they became fast friends. Their mutual admiration survived World War I, during which Einstein advocated pacifism and Planck signed the infamous Manifesto of the 93 Intellectuals supporting the German invasion of Belgium. It also survived the Weimar Republic, which Einstein favored and Planck disliked. Physics drew them together, as both opposed the Copenhagen Interpretation; so did common decency, as Planck helped to protect Einstein from anti-semitic attacks. Their friendship did not survive the Nazis. As a standing secretary of the Berlin Academy, Planck had to advise Einstein to resign from it before his colleagues, outraged at his criticism of the new Germany from the safety of California, expelled him. Einstein never forgave his old friend and former fellow artist for not protesting publicly against his expulsion and denigration, and other enormities of National Socialism. .
Einstein's Clocks and Langevin's Twins
Weinstein, Galina
2012-01-01
In 1905 Einstein presented the Clock Paradox and in 1911 Paul Langevin expanded Einstein's result to human observers, the "Twin Paradox." I will explain the crucial difference between Einstein and Langevin. Einstein did not present the so-called "Twin Paradox." Later Einstein continued to speak about the clock paradox. Einstein might not have been interested in the question: what happens to the observers themselves. The reason for this could be the following; Einstein dealt with measurement procedures, clocks and measuring rods. Einstein's observers were measuring time with these clocks and measuring rods. Einstein might not have been interested in so-called biology of the observers, whether these observers were getting older, younger, or whether they have gone any other changes; these changes appeared to be out of the scope of his "Principle of relativity" or kinematics. The processes and changes occurring within observers seemed to be good for philosophical discussions. Later writers criticized Einstein's c...
Calaprice, Alice; Schulmann, Robert
2015-01-01
This is the single most complete guide to Albert Einstein’s life and work for students, researchers, and browsers alike. Written by three leading Einstein scholars who draw on their combined wealth of expertise gained during their work on the Collected Papers of Albert Einstein, this authoritative and accessible reference features more than one hundred entries and is divided into three parts covering the personal, scientific, and public spheres of Einstein’s life. An Einstein Encyclopedia contains entries on Einstein’s birth and death, family and romantic relationships, honors and awards, educational institutions where he studied and worked, citizenships and immigration to America, hobbies and travels, plus the people he befriended and the history of his archives and the Einstein Papers Project. Entries on Einstein’s scientific theories provide useful background and context, along with details about his assistants, collaborators, and rivals, as well as physics concepts related to his work. Coverage o...
CERN
1979-01-01
Homage to Albert Einstein, the giant of twentieth-century physics born exactly 100 years ago on 14 March 1879 in Ulm, Germany. At the height of his career, Einstein made a whole series of monumental contributions to physics, including the elaborate theories of special and general relativity which revolutionized human thought and marked a major breakthrough in our understanding to the Universe. Along with quantum mechanics, relativity is one of the twin pillars of understanding which allow us here at CERN to study the behaviour of the tiniest components of matter. The development of quantum mechanics took the combined efforts of some of the greatest scientists the world has known, while relativity was developed almost single-handed by Einstein. The scientist and his work by D. Amati and S. Fubini. A socially engaged scientist by V. F. Weisskopf. On the origin of the Einstein-Russell statement on nuclear weapon by H. S. Burhop.
Herwig Schopper Einstein's Legacy
Schneegans, Susan
2005-01-01
"Last June, the United Nations declared 2005 the International Year of Physics and invited UNESCO to take the lead in celebrating the hundreth anniversary of Albert Einstein's legandary articles on relativisty, quantum theory and Brownian motion" (3 pages)
Calaprice, Alice
2005-01-01
Albert Einstein was an exceptional human being. Perhaps nothing reflects the breadth and scope of his brilliance, his interests, and his influence better than his publications -- more than six hundred scientific papers, books, essays, reviews, and opinion pieces. Einstein began publishing in March 1901 with a scientific work that appeared in the German journal Annalen der Physik when he was twenty-two; the last publication was an editorial in the journal Common Cause which appeared a few months before his death in 1955. In the fifty-four-year interval, his published work ranged widely over relativity theory and quantum physics, nationalism, Judaism, war, peace, and education. Indeed, Einstein's literary output was so abundant that even many of his most informed admirers are not familiar with all of it. The Einstein Almanac takes a look at Einstein's year-by-year output, explaining his three-hundred most important publications and setting them into the context of his life, science, and world history. Concentr...
Albert Einstein memorial lectures
Mechoulam, Raphael; The Israel Academy for Sciences and Humanities
2012-01-01
This volume consists of a selection of the Albert Einstein Memorial Lectures presented annually at the Israel Academy of Sciences and Humanities. Delivered by eminent scientists and scholars, including Nobel laureates, they cover a broad spectrum of subjects in physics, chemistry, life science, mathematics, historiography and social issues. This distinguished memorial lecture series was inaugurated by the Israel Academy of Sciences and Humanities following an international symposium held in Jerusalem in March 1979 to commemorate the centenary of Albert Einstein's birth. Considering that Einstein's interests, activities and influence were not restricted to theoretical physics but spanned broad fields affecting society and the welfare of humankind, it was felt that these memorial lectures should be addressed to scientists, scholars and erudite laypersons rather than to physicists alone.
Conversations With Albert Einstein. II
Shankland, R. S.
1973-01-01
Discusses Einstein's views on the role of Michelson-Morley, Fizeau, and Miller experiments in the development of relativity and his attitude toward the theories of new quantum mechanics. Indicates that Einstein's opposition to quantum mechanics is beyond dispute. (CC)
Einstein, Albert
2009-01-01
His name is synonymous with ""genius,"" but these essays by the renowned physicist and scholar are accessible to any reader. In addition to outlining the core of relativity theory in everyday language, Albert Einstein presents fascinating discussions of other scientific fields to which he made significant contributions. The Nobel Laureate also profiles some of history's most influential physicists, upon whose studies his own work was based.Assembled during Einstein's lifetime from his speeches and essays, this book marks the first presentation to the wider world of the scientist's accomplishme
Ceremony marking Einstein Year
2005-01-01
Sunday 13th November at 10:00amat Geneva's St. Peter's Cathedral To mark Einstein Year and the importance of the intercultural dialogue of which it forms a part, a religious service will take place on Sunday 13 November at 10 a.m. in St. Peter's Cathedral, to which CERN members and colleagues are warmly welcomed. Pastor Henry Babel, senior minister at the Cathedral, will speak on the theme: 'God in Einstein's Universe'. Diether Blechschmidt will convey a message on behalf of the scientific community.
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 4. Bose–Einstein Condensation - Birds of a Feather Flock Together. Rajaram Nityananda. General Article Volume 5 Issue 4 April 2000 pp 46-51. Fulltext. Click here to view fulltext PDF. Permanent link:
Indian Academy of Sciences (India)
gas of photons which explained Planck's law for thermal radiation at one ... their first application. Seventy years later they are being used in atomic physics laboratories all over the world. Everybody is talking about Bose-Einstein condensation. This ... distribution of the position of any particle in the gas is a constant function ...
Löffler, Frank
2012-03-01
The Einstein Toolkit Consortium is developing and supporting open software for relativistic astrophysics. Its aim is to provide the core computational tools that can enable new science, broaden our community, facilitate interdisciplinary research and take advantage of petascale computers and advanced cyberinfrastructure. The Einstein Toolkit currently consists of an open set of over 100 modules for the Cactus framework, primarily for computational relativity along with associated tools for simulation management and visualization. The toolkit includes solvers for vacuum spacetimes as well as relativistic magneto-hydrodynamics, along with modules for initial data, analysis and computational infrastructure. These modules have been developed and improved over many years by many different researchers. The Einstein Toolkit is supported by a distributed model, combining core support of software, tools, and documentation in its own repositories and through partnerships with other developers who contribute open software and coordinate together on development. As of January 2012 it has 68 registered members from 30 research groups world-wide. This talk will present the current capabilities of the Einstein Toolkit and will point to information how to leverage it for future research.
Indian Academy of Sciences (India)
Home; Fellowship. Fellow Profile. Elected: 1936 Honorary. Einstein, Prof. Albert Nobel Laureate (Physics) - 1921. Date of birth: 14 March 1879. Date of death: 18 April 1955. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the Three Science ...
Examining the Enigmatic Einstein
Khoon, Koh Aik
2007-01-01
Albert Einstein is the icon of scientific genius. His is one the most recognizable faces in the history of mankind. This paper takes a cursory look at the man who is commonly perceived to be the epitome of eccentricity. We manage to sum up his salient traits which are associated with his name. The traits are based on anecdotal evidence. This…
Atkinson, David
2005-01-01
The Michelson-Morley experiment suggests the hypothesis that the two-way speed of light is constant,and this is consistent with a more general in variance than that of Lorentz. On adding the requirement that physical laws have the same form in all inertial frames, as Einstein did, the transformation
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 12. Bose-Einstein Condensation - Birds of a Feather Flock Together. Rajaram Nityananda. Volume 10 Issue 12 December 2005 pp 142-147. Fulltext. Click here to view fulltext PDF. Permanent link:
Dzhunushaliev, Vladimir
2010-01-01
Stochastic Einstein equations are considered when 3D space metric $\\gamma_{ij}$ are stochastic functions. The probability density for the stochastic quantities is connected with the Perelman's entropy functional. As an example, the Friedman Universe is considered. It is shown that for the Friedman Universe the dynamical evolution is not changed. The connection between general relativity and Ricci flows is discussed.
Indian Academy of Sciences (India)
tric effect. Figure 2 (right). Kanji script on the surface of copper with the aid of diffusing iron atoms. GENERAL I ARTICLE mathematics itself but to understand the phenomenon of gravity and ... ian motion and the photo electric effect is Einstein's usage of ... dilute solution of sugar molecules as solutes, dissolved in water as ...
Weisskopf, Victor Frederick; CERN. Geneva
1979-01-01
A socially engaged scientist by V. F. WEISSKOPF. On the origin of the Einstein-Russell statement on nuclear weapon by H. S. BURHOP. This week, we pay homage to Albert Einstein, the giant of twentieth-century physics born exactly 100 years ago on 14 March 1879 in Ulm, Germany. At the height of his career, Einstein made a whole series of monumental contributions to physics, including the elaborate theories of special and general relativity which revolutionized human thought and marked a major breakthrough in our understanding to the Universe. Along with quantum mechanics, relativity is one of the twin pillars of understanding which allow us here at CERN to study the behaviour of the tiniest components of matter. The development of quantum mechanics took the combined efforts of some of the greatest scientists the world has known, while relativity was developed almost single-handed by Einstein. The centenary of his birth is being commemorated all over the world. Exhibitions and symposia are being organized, books...
2003-01-01
For the first time scientists have succeeded in measuring the speed of gravity. They took advantage of a rare alignment of Jupiter against a far-off quasar to measure the fundamental constant described by Albert Einstein in his general theory of relativity (2 pages).
2011-03-01
ASA has announced the selection of the 2011 Einstein Fellows who will conduct research related to NASA's Physics of the Cosmos program, which aims to expand our knowledge of the origin, evolution, and fate of the Universe. The Einstein Fellowship provides support to the awardees for three years, and the Fellows may pursue their research at a host university or research center of their choosing in the United States. The new Fellows will begin their programs in the fall of 2011. The new Einstein Fellows and their host institutions are listed below: * Akos Bogdan (Smithsonian Astrophysical Observatory, Cambridge, Mass.) * Samuel Gralla (University of Maryland, College Park, Md.) * Philip Hopkins (University of California at Berkeley) * Matthew Kunz (Princeton University, Princeton, N.J.) * Laura Lopez (Massachusetts Institute of Technology, Cambridge, Mass.) * Amy Reines (National Radio Astronomy Observatory, Charlottesville, Virg.) * Rubens Reis (University of Michigan, Ann Arbor) * Ken Shen (Lawrence Berkeley National Laboratory, Berkeley, Calif.) * Jennifer Siegal-Gaskins (California Institute of Technology, Pasadena) * Lorenzo Sironi (Harvard University, Cambridge, Mass.) NASA has two other astrophysics theme-based fellowship programs: the Sagan Fellowship Program, which supports research into exoplanet exploration, and the Hubble Fellowship Program, which supports research into cosmic origins. More information on the Einstein Fellowships can be found at: http://cxc.harvard.edu/fellows/
Breithaupt, Jim
2000-01-01
This guide contains the essential facts and concepts of the life and work of Albert Einstein. It examines his background and the scientific method of the day, and explains his theories in simple terms. Central themes are presented in jargon-free language and key terms are highlighted and explained.
Taming the nonlinearity of the Einstein equation.
Harte, Abraham I
2014-12-31
Many of the technical complications associated with the general theory of relativity ultimately stem from the nonlinearity of Einstein's equation. It is shown here that an appropriate choice of dynamical variables may be used to eliminate all such nonlinearities beyond a particular order: Both Landau-Lifshitz and tetrad formulations of Einstein's equation are obtained that involve only finite products of the unknowns and their derivatives. Considerable additional simplifications arise in physically interesting cases where metrics become approximately Kerr or, e.g., plane waves, suggesting that the variables described here can be used to efficiently reformulate perturbation theory in a variety of contexts. In all cases, these variables are shown to have simple geometrical interpretations that directly relate the local causal structure associated with the metric of interest to the causal structure associated with a prescribed background. A new method to search for exact solutions is outlined as well.
Energy Technology Data Exchange (ETDEWEB)
Giannetto, E [Dipartimento di Fisica ' A Volta' , via A Bassi 6, I-27100 Pavia (Italy)
2007-07-20
Thibault Damour is a theoretical physicist, and a member of the French Academy of Sciences. This book is the translation, by Eric Novak, of the original French Si Einstein m'etait conte (Le Cherche Midi, 2005). It is neither a book of theoretical physics nor a biography of Einstein. It is not a book of history nor philosophy of science. In Damour's words it was written to encourage the reader to share with Einstein 'those times when he understood some part of the hidden order of the universe'. It is a relatively short book, written in a very fluent style, but it deals with all the major problems and achievements of Einstein's works. Starting from special relativity, it continues with general relativity, quantum theories, unified field theory and a brief overview of the actual research related to Einstein's legacy. It is essentially a popular science book with some related exploration in history and philosophy to interpret physical theories. The most important problem discussed by Damour is the nature of time. On this subject, there is a very interesting short paragraph (pp 33--35) dedicated to the reception of the relativity idea by the great writer Marcel Proust and its counterpart within A la Recherche du Temps Perdu. A correct discussion of the implications of a relativistic time should imply the distinction of the different possible interpretations of this concept. Damour seems to conclude that only one interpretation is possible: 'time does not exist', flowing of time is an illusion. One has to know that Einstein's ideas on time were related to Spinoza's perspective of a knowledge sub specie aeternitatis. However, other interpretations are possible and are related to the idea of time as an actuality. Damour speaks about the controversy between Einstein and Bergson, but Bergson is considered as a philosopher who did not understand relativity. This philosophical problem of relativistic time is indeed related to a
Einstein and a century of time
Raine, D. J.
2005-09-01
this pivotal insight into the role of theory when it came to quantum mechanics. Much has been written about this and we do not add to it in this collection. Quantum theory is a consistent description of nature whatever Einstein may think of 'god' for making it so. Many of us would side with Einstein in hoping it will yet turn out not to be a complete description. This will not happen, as Einstein hoped throughout his later work, from a return to classical field theory. But quantum behaviour is a universal property of matter and may therefore be expected, according to Einstein's way of thought, to have a geometrical origin. The advent of non-commutative quantum geometries may turn out to be a step in this direction. My own introduction to Einstein's physics was through what has come to be known as Mach's principle. My research supervisor, Dennis Sciama, in what he always claimed was probably Einstein's last significant scientific conversation, talked with him on this subject, during which Einstein explained that he had abandoned the idea of Mach's principle. This principle had been a guiding thought in the development of general relativity, but superfluous to its final exposition. It can be interpreted variously as the determination of the local compass of inertia by the distant stars, the non-rotation of the Universe or, more restrictedly, as requiring a critical density universe (to generate the right amount of inertia). This last formulation amounts to Gρτ2 approx 1, where ρ is the density of the Universe at time τ. This appears to be a classical expression, which would probably be sufficient to relegate Mach's principle to mere historical interest along with the classical unified field theories. It is also usually considered to be accounted for by inflation, which drives the Universe to Ω=1. However, we can also think of the expression as saying that the Universe has a Planck mass in a Planck volume at the Planck time: G=(hc / G)1/2(c3 / Gh)3/2(Gh / c5)=1. This
Exploring dynamic localization with a Bose-Einstein condensate
Eckardt, Andre; Holthaus, Martin; Lignier, Hans; Zenesini, Alessandro; Ciampini, Donatella; Morsch, Oliver; Arimondo, Ennio
2008-01-01
We report on the experimental observation of dynamic localization of a Bose-Einstein condensate in a shaken optical lattice, both for sinusoidal and square-wave forcing. The formulation of this effect in terms of a quasienergy band collapse, backed by the excellent agreement of the observed collapse points with the theoretical predictions, suggests the feasibility of systematic quasienergy band engineering.
Einstein the searcher his work explained from dialogues with Einstein
Moszkowski, Alexander
2014-01-01
This volume, first published in 1921, presents a series of portraits of Einstein, thus offering glimpses in the character and private reflections of the man who changed the course of modern science. Intended neither as a biography, nor as a résumé of Einsteinian physics, Einstein: The Searcher instead focusses on Einstein's relationship with the scientific project as he himself conceived it, and so is still of contemporary significance for those puzzled by the spirit of scientific enquiry.
Yunes, Nicolas
2015-01-01
This is an article commissioned by the Spanish Physics Magazine ("Revista Espa\\~nola de F\\'isica") for the Centennial Anniversary of the discovery of General Relativity. The article reviews experimental and observational efforts to test Einstein's theory of General Relativity in a variety of scenarios (from the Solar System to binary pulsars, from the Sag A* to binary black hole and neutron star coalescences).
Herweck, Don
2009-01-01
Albert Einstein is probably the most influential scientist and greatest physicist of the twentieth century. He revolutionized our ideas about time and space, and he is best known for his theory of relativity and his equation E=mc2, which explains the relationship between energy and mass. By age 30, he was considered by many to be one of the world's greatest scientific thinkers.
Directory of Open Access Journals (Sweden)
Jou, David
2007-12-01
Full Text Available We study Einstein’s contributions to thermodynamics and statistical physics and their influence on some fields of physics which have led to current studies on complexity. We focus our attention on the use of fluctuations and entropy as a common framework for light and matter, whcich leds him to some of his fundamental contributions (phtoelectric effect, Brownian motion, specific heat of solids, stimulated light emission, Bose-Einstein condensation. We underline some aspects of Einstein’s research style: extrapolations, analogies, simplifications. We underline the relationship between light and matter as a common link of his researches in statistical physics.Presentamos las contribuciones de Einstein a la termodinámica y la mecánica estadística y su resonancia en ramas de la física que han conducido hasta la consideración actual de lo complejo. Nos referimos especialmente al uso de las fluctuaciones y de la entropía como marco común y nexo de unión entre luz y materia, que le conducen a algunas de sus aportaciones fundamentales (efecto fotoeléctrico, movimiento browniano, calor específico de los sólidos, emisión estimulada de la luz, condensación de Bose-Einstein. Consideramos también algunas facetas del estilo de investigación de Einstein, que se manifiestan con especial claridad en este campo: extrapolaciones, analogías, simplificaciones. Destacamos especialmente la importancia de la relación entre luz y materia en sus investigaciones.
Albert Einstein, Analogizer Extraordinaire
CERN. Geneva
2007-01-01
Where does deep insight in physics come from? It is tempting to think that it comes from the purest and most precise of reasoning, following ironclad laws of thought that compel the clear mind completely rigidly. And yet the truth is quite otherwise. One finds, when one looks closely at any major discovery, that the greatest of physicists are, in some sense, the most crazily daring and irrational of all physicists. Albert Einstein exemplifies this thesis in spades. In this talk I will describe the key role, throughout Albert Einstein's fabulously creative life, played by wild guesses made by analogy lacking any basis whatsoever in pure reasoning. In particular, in this year of 2007, the centenary of 1907, I will describe how over the course of two years (1905 through 1907) of pondering, Einstein slowly came, via analogy, to understand the full, radical consequences of the equation that he had first discovered and published in 1905, arguably the most famous equation of all time: E = mc2.
Amati, Daniele; Weisskopf, Victor Frederick; CERN. Geneva
1979-01-01
The scientist and his work by D. AMATI and S. FUBINI. A socially engaged scientist by V. F. WEISSKOPF. This week, we pay homage to Albert Einstein, the giant of twentieth-century physics born exactly 100 years ago on 14 March 1879 in Ulm, Germany. At the height of his career, Einstein made a whole series of monumental contributions to physics, including the elaborate theories of special and general relativity which revolutionized human thought and marked a major breakthrough in our understanding to the Universe. Along with quantum mechanics, relativity is one of the twin pillars of understanding which allow us here at CERN to study the behaviour of the tiniest components of matter. The development of quantum mechanics took the combined efforts of some of the greatest scientists the world has known, while relativity was developed almost single-handed by Einstein. The centenary of his birth is being commemorated all over the world. Exhibitions and symposia are being organized, books published, postage stamps is...
Horizon thermodynamics from Einstein's equation of state
Hansen, Devin; Kubizňák, David; Mann, Robert B.
2017-08-01
By regarding the Einstein equations as equation(s) of state, we demonstrate that a full cohomogeneity horizon first law can be derived in horizon thermodynamics. In this approach both the entropy and the free energy are derived concepts, while the standard (degenerate) horizon first law is recovered by a Legendre projection from the more general one we derive. These results readily generalize to higher curvature gravities where they naturally reproduce a formula for the entropy without introducing Noether charges. Our results thus establish a way of how to formulate consistent black hole thermodynamics without conserved charges.
Horizon thermodynamics from Einstein's equation of state
Directory of Open Access Journals (Sweden)
Devin Hansen
2017-08-01
Full Text Available By regarding the Einstein equations as equation(s of state, we demonstrate that a full cohomogeneity horizon first law can be derived in horizon thermodynamics. In this approach both the entropy and the free energy are derived concepts, while the standard (degenerate horizon first law is recovered by a Legendre projection from the more general one we derive. These results readily generalize to higher curvature gravities where they naturally reproduce a formula for the entropy without introducing Noether charges. Our results thus establish a way of how to formulate consistent black hole thermodynamics without conserved charges.
Grundmann, Siegfried
2004-01-01
In 1919 the Prussian Ministry of Science, Arts and Culture opened a dossier on "Einstein's Theory of Relativity." It was rediscovered by the author in 1961 and is used in conjunction with numerous other subsequently identified 'Einstein' files as the basis of this fascinating book. In particular, the author carefully scrutinizes Einstein's FBI file from 1950-55 against mostly unpublished material from European including Soviet sources and presents hitherto unknown documentation on Einstein's alleged contacts with the German Communist Party and the Comintern. Siegfried Grundmann's thorough study of Einstein's participation on a committee of the League of Nations, based on archival research in Geneva, is also new. This book outlines Einstein's image in politics and German science policy. It covers the period from his appointment as a researcher in Berlin to his fight abroad against the "boycott of German science" after World War I and his struggle at home against attacks on "Jewish physics" of which he was made...
Constraint damping in the Z4 formulation and harmonic gauge
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Gundlach, Carsten [School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom); Calabrese, Gioel [School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom); Hinder, Ian [School of Mathematics, University of Southampton, Southampton SO17 1BJ (United Kingdom); Martin-GarcIa, Jose M [Instituto de Estructura de la Materia, Centro de Fisica Miguel A Catalan, CSIC, Serrano 123, 28006 Madrid (Spain)
2005-09-07
We show that by adding suitable lower-order terms to the Z4 formulation of the Einstein equations, all constraint violations except constant modes are damped. This makes the Z4 formulation a particularly simple example of a {lambda}-system as suggested by Brodbeck et al (1999 J. Math. Phys. 40 909). We also show that the Einstein equations in harmonic coordinates can be obtained from the Z4 formulation by a change of variables that leaves the implied constraint evolution system unchanged. Therefore, the same method can be used to damp all constraints in the Einstein equations in harmonic gauge.
What, Precisely, Is "Thinking"? Einstein's Answer.
Holton, Gerald
1979-01-01
Gives an analysis of how Einstein viewed "thinking," and the nature of scientific discovery, using extensive quotations from Einstein's own writings, and especially from his essay "Autobiographical Notes."
Warped products and Einstein metrics
Energy Technology Data Exchange (ETDEWEB)
Kim, Seongtag [Department of Mathematics Education, Inha University, Incheon 402-751 (Korea, Republic of)
2006-05-19
Warped product construction is an important method to produce a new metric with a base manifold and a fibre. We construct compact base manifolds with a positive scalar curvature which do not admit any non-trivial Einstein warped product, and noncompact complete base manifolds which do not admit any non-trivial Ricci-flat Einstein warped product. (letter to the editor)
Albert Einstein: A Biographical Sketch
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 4. Albert Einstein: A Biographical Sketch. Maja Winteler-Einstein. Reflections Volume 5 Issue 4 April 2000 pp 111-120. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/005/04/0111-0120 ...
Stachel, John
2002-01-01
John Stachel, the author of this collection of 37 published and unpublished articles on Albert Einstein, has written about Einstein and his work for over 40 years. Trained as a theoretical physicist specializing in the theory of relativity, he was chosen as the founding editor of The Collected papers of Albert Einstein 25 years ago, and is currently Director of the Boston University Center for Einstein Studies. Based on a detailed study of documentary evidence, much of which was newly discovered in the course of his work, Stachel debunks many of the old (and some new) myths about Einstein and offers novel insight into his life and work. Throughout the volume, a new, more human picture of Einstein is offered to replace the plaster saint of popular legend. In particular, a youthful Einstein emerges from the obscurity that previously shrouded his early years, and much new light is shed on the origins of the special and general theories of relativity. Also discussed in some detail are Einstein's troubled relatio...
Physics Today, 1979
1979-01-01
Celebrates the centennial of Einstein's birth with an eight-page pictorial biography and two special articles: (1) Einstein the catalyst; and (2) Unitary field theories. His special and general theories of relativity and his contributions to quantum physics and other topics are also presented. (HM)
Einstein Inflationary Probe (EIP)
Hinshaw, Gary
2004-01-01
I will discuss plans to develop a concept for the Einstein Inflation Probe: a mission to detect gravity waves from inflation via the unique signature they impart to the cosmic microwave background (CMB) polarization. A sensitive CMB polarization satellite may be the only way to probe physics at the grand-unified theory (GUT) scale, exceeding by 12 orders of magnitude the energies studied at the Large Hadron Collider. A detection of gravity waves would represent a remarkable confirmation of the inflationary paradigm and set the energy scale at which inflation occurred when the universe was a fraction of a second old. Even a strong upper limit to the gravity wave amplitude would be significant, ruling out many common models of inflation, and pointing to inflation occurring at much lower energy, if at all. Measuring gravity waves via the CMB polarization will be challenging. We will undertake a comprehensive study to identify the critical scientific requirements for the mission and their derived instrumental performance requirements. At the core of the study will be an assessment of what is scientifically and experimentally optimal within the scope and purpose of the Einstein Inflation Probe.
Suzuki, Yoichiro
2005-01-01
A tiny neutrino mass is a clue to the physics beyond the standard model of elementary particle physics. The primary cosmic rays, mostly protons, are created and accelerated to the relativistic energy in supernova remnants. They traverse the universe and reach the earth. The incoming primary cosmic rays interact with the earth's atmosphere to produce secondary particles, which subsequently decay into neutrinos, called atmospheric neutrinos. The atmospheric neutrinos have shown the evidence of the finite neutrino masses through the phenomena called neutrino oscillations. Neutrinos are detected by large detectors underground like, for example, Super-Kamiokande, SNO and KamLAND. Those detectors use large photomultiplier tubes, which make use of the photo-electric effect to convert photons created by the interaction of neutrinos to electrons to form electric pulses. Neutrinos are therefore created and detected by "Einstein" and have step forward beyond the current physics. Neutrinos may also carry a hit to the ori...
Correct Linearization of Einstein's Equations
Directory of Open Access Journals (Sweden)
Rabounski D.
2006-06-01
Full Text Available Regularly Einstein's equations can be reduced to a wave form (linearly dependent from the second derivatives of the space metric in the absence of gravitation, the space rotation and Christoffel's symbols. As shown here, the origin of the problem is that one uses the general covariant theory of measurement. Here the wave form of Einstein's equations is obtained in the terms of Zelmanov's chronometric invariants (physically observable projections on the observer's time line and spatial section. The obtained equations depend on solely the second derivatives even if gravitation, the space rotation and Christoffel's symbols. The correct linearization proves: the Einstein equations are completely compatible with weak waves of the metric.
Einstein and the Atomic Theory
O'Raifeartaigh, Cormac
2005-01-01
In the year 1905, a young Albert Einstein published a number of scientific papers that changed physics forever. The best known of these, the Special Theory of Relativity, quickly established the young Einstein as a scientist of note (see J.IEI vol. 59:6) and led to Einstein’s General Theory of Relativity, one of the pillars of modern physics. In a second paper, Einstein published a controversial proposal concerning the nature of light that later formed a cornerstone of quantum theory, the ...
Einstein equations and conformal structure: Existence of Anti-de Sitter-type space-times
Friedrich, Helmut
1995-10-01
We discuss Einstein's equations in the context of normal conformal Cartan connections, derive a new conformal representation of the equations, and express the equations in a conformally invariant gauge. The resulting formulation of the equations is used to show the existence of asymptotically simple solutions to Einstein's equations with a positive cosmological constant. The solutions are characterized by Cauchy data on a space-like slice and by the intrinsic conformal structure on the conformal boundary at space-like and null infinity.
Physics before and after Einstein
Capria, M Mamone
2005-01-01
It is now a century ago that one of the icons of modern physics published some of the most influential scientific papers of all times. With his work on relativity and quantum theory, Albert Einstein has altered the field of physics forever. It should not come as a surprise that looking back at Einstein''s work, one needs to rethink the whole scope of physics, before and after his time. This books aims to provide a perspective on the history of modern physics, spanning from the late 19th century up to today. It is not an encyclopaedic work, but it presents the groundbreaking and sometimes provocative main contributions by Einstein as marking the line between ''old'' and ''new'' physics, and expands on some of the developments and open issues to which they gave rise.
Pesic, Peter
2003-11-01
Einstein was the first to discuss and resolve the 'twin paradox', which in 1905 he did not consider paradoxical and treated as a consequence of lack of simultaneity. He maintained this view until at least 1914. However, in 1918 Einstein brought forward arguments about accelerated frames of reference that tended to overshadow his initial resolution. His earlier arguments were gradually rediscovered during the subsequent controversy about this 'paradox'.
The NASA Beyond Einstein Program
White, Nicholas E.
2006-01-01
Einstein's legacy is incomplete, his theory of General relativity raises -- but cannot answer --three profound questions: What powered the big bang? What happens to space, time, and matter at the edge of a black hole? and What is the mysterious dark energy pulling the Universe apart? The Beyond Einstein program within NASA's Office of Space Science aims to answer these questions, employing a series of missions linked by powerful new technologies and complementary approaches towards shared science goals. The Beyond Einstein program has three linked elements which advance science and technology towards two visions; to detect directly gravitational wave signals from the earliest possible moments of the BIg Bang, and to image the event horizon of a black hole. The central element is a pair of Einstein Great Observatories, Constellation-X and LISA. Constellation-X is a powerful new X-ray observatory dedicated to X-Ray Spectroscopy. LISA is the first spaced based gravitational wave detector. These powerful facilities will blaze new paths to the questions about black holes, the Big Bang and dark energy. The second element is a series of competitively selected Einstein Probes, each focused on one of the science questions and includes a mission dedicated resolving the Dark Energy mystery. The third element is a program of technology development, theoretical studies and education. The Beyond Einstein program is a new element in the proposed NASA budget for 2004. This talk will give an overview of the program and the missions contained within it.
Afanassjewa en Einstein. Wederzijdse waardering
Directory of Open Access Journals (Sweden)
Margriet van der Heijden
2016-10-01
Full Text Available Afanassjewa and EinsteinIn 1912 Tatiana Afanassjewa (1876–1964, a Russian mathematician, arrived in Leiden. The university in this city had an amazingly flourishing physics department. Afanassjewa accompanied her husband Paul Ehrenfest (1880–1933, a theoretical physicist from Vienna, who was to become successor to the famous professor Hendrik Antoon Lorentz. Soon the couple’s house became a regular meeting place for Dutch mathematicians and physicists, and a temporary home for many learned guests from all over the world. Among them was Albert Einstein, a close friend of Ehrenfest, with whom he shared a passion for physics and music. This paper recapitulates their friendship and includes new details about Afanassjewa, who was to initiate a fierce debate on the didactics of mathematics in The Netherlands and whose sharp and analytical mind made an impression on Einstein. Both the Ehrenfest-Afanassjewa couple and Einstein had a vivid interest in international relations and, the role of science therein. Afanassjewa and Einstein stayed in touch through letters and cards after Ehrenfest’s untimely death in 1933, the year when Hitler rose to power in Germany and Einstein moved to the United States.
Elvis, Martin; Plummer, David; Schachter, Jonathan; Fabbiano, G.
1992-01-01
A catalog of 819 sources detected in the Einstein IPC Slew Survey of the X-ray sky is presented; 313 of the sources were not previously known as X-ray sources. Typical count rates are 0.1 IPC count/s, roughly equivalent to a flux of 3 x 10 exp -12 ergs/sq cm s. The sources have positional uncertainties of 1.2 arcmin (90 percent confidence) radius, based on a subset of 452 sources identified with previously known pointlike X-ray sources (i.e., extent less than 3 arcmin). Identifications based on a number of existing catalogs of X-ray and optical objects are proposed for 637 of the sources, 78 percent of the survey (within a 3-arcmin error radius) including 133 identifications of new X-ray sources. A public identification data base for the Slew Survey sources will be maintained at CfA, and contributions to this data base are invited.
Historical Approach to Physics according to Kant, Einstein, and Hegel
Kim, Y S
2013-01-01
It is known that Einstein's conceptual base for his theory of relativity was the philosophy formulated by Immanuel Kant. Things appear differently to observers in different frames. However, Kant's Ding-an-Sich leads to the existence of the absolute reference frame which is not acceptable in Einstein's theory. It is possible to avoid this conflict using the ancient Chinese philosophy of Taoism where two different views can co-exist in harmony. This is not enough to explain Einstein's discovery of the mass-energy relation. The energy-momentum relations for slow and ultra-fast particles take different forms. Einstein was able to synthesize these two formulas to create his energy-mass relation. Indeed, this is what Hegelianism is about in physics. Isaac Newton synthesized open orbits for comets and closed orbits for planets to create his second law of motion. Maxwell combined electricity and magnetism to create his four equations to the present-day wireless world. In order to synthesize wave and particle views of...
CERN physicist receives Einstein Medal
2006-01-01
On 29 June the CERN theorist Gabriele Veneziano was awarded the prestigious Albert Einstein Medal for significant contributions to the understanding of string theory. This award is given by the Albert Einstein Society in Bern to individuals whose scientific contributions relate to the work of Einstein. Former recipients include exceptional physicists such as Murray Gell-Mann last year, but also Stephen Hawking and Victor Weisskopf. Gabriele Veneziano, a member of the integrated CERN Theory Team since 1977, led the Theory Division from 1994 to 1997 and has already received many prestigious prizes for his outstanding work, including the Enrico Fermi Prize (see CERN Courier, November 2005), the Dannie Heineman Prize for mathematical physics of the American Physical Society in 2004 (see Bulletin No. 47/2003), and the I. Ya. Pomeranchuk Prize of the Institute of Theoretical and Experimental Physics (Moscow) in 1999.
Einstein metrics on tangent bundles of spheres
Energy Technology Data Exchange (ETDEWEB)
Dancer, Andrew S [Jesus College, Oxford University, Oxford OX1 3DW (United Kingdom); Strachan, Ian A B [Department of Mathematics, University of Hull, Hull HU6 7RX (United Kingdom)
2002-09-21
We give an elementary treatment of the existence of complete Kaehler-Einstein metrics with nonpositive Einstein constant and underlying manifold diffeomorphic to the tangent bundle of the (n+1)-sphere.
Einstein Equations from Varying Complexity
Czech, Bartłomiej
2018-01-01
A recent proposal equates the circuit complexity of a quantum gravity state with the gravitational action of a certain patch of spacetime. Since Einstein's equations follow from varying the action, it should be possible to derive them by varying complexity. I present such a derivation for vacuum solutions of pure Einstein gravity in three-dimensional asymptotically anti-de Sitter space. The argument relies on known facts about holography and on properties of tensor network renormalization, an algorithm for coarse-graining (and optimizing) tensor networks.
Einstein, Nobel Prize, and Accelerators
Jarlskog, C
2005-01-01
We are celebrating the year of physics thanks to Einsteins monumental contributions a hundred years ago. Indeed, the current field of accelerator physics is also deeply indebted to him. Why did it take more than a decade and a half for him to be "crowned" in Stockholm by the Nobel Prize? Did he get the Prize for the "wrong" thing? Based on original material from the archives of the Swedish Academy of Sciences, I will discuss how Einstein got the Nobel Prize and will give a short summary of his everlasting impact on the field of accelerator physics.
Indian Academy of Sciences (India)
Einstein's explosive creativity in 1905. Clark cannot be blamed for this - there is indeed little in Einstein's life to which this can be confidently traced. One may talk of Einstein's attitudes and determination, but a thousand others now forgotten must have shared them. There are a few papers before 1905, but no real signs of a ...
Series expansion of the modified Einstein Procedure
Seema Chandrakant Shah-Fairbank
2009-01-01
This study examines calculating total sediment discharge based on the Modified Einstein Procedure (MEP). A new procedure based on the Series Expansion of the Modified Einstein Procedure (SEMEP) has been developed. This procedure contains four main modifications to MEP. First, SEMEP solves the Einstein integrals quickly and accurately based on a series expansion. Next,...
Einstein for Schools and the General Public
Johansson, K. E.; Kozma, C; Nilsson, Ch
2006-01-01
In April 2005 the World Year of Physics (Einstein Year in the UK and Ireland) was celebrated with an Einstein week in Stockholm House of Science. Seven experiments illustrated Einstein's remarkable work in 1905 on Brownian motion, the photoelectric effect and special relativity. Thirteen school classes with 260 pupils, 30 teachers and 25 members…
Quantum Einstein's equations and constraints algebra
Indian Academy of Sciences (India)
If we are interested in seeing the symmetry breaking at this level, we must look at quantum Einstein's equations. This point is explained in the next section. 3. Quantum Einstein's equations. Previously [5] in the Bohmian quantum gravity framework, we have studied the modifi- cations of Einstein's equations in some special ...
Einstein Gravity, Lagrange-Finsler Geometry, and Nonsymmetric Metrics
Directory of Open Access Journals (Sweden)
Sergiu I. Vacaru
2008-10-01
Full Text Available We formulate an approach to the geometry of Riemann-Cartan spaces provided with nonholonomic distributions defined by generic off-diagonal and nonsymmetric metrics inducing effective nonlinear and affine connections. Such geometries can be modelled by moving nonholonomic frames on (pseudo Riemannian manifolds and describe various types of nonholonomic Einstein, Eisenhart-Moffat and Finsler-Lagrange spaces with connections compatible to a general nonsymmetric metric structure. Elaborating a metrization procedure for arbitrary distinguished connections, we define the class of distinguished linear connections which are compatible with the nonlinear connection and general nonsymmetric metric structures. The nonsymmetric gravity theory is formulated in terms of metric compatible connections. Finally, there are constructed such nonholonomic deformations of geometric structures when the Einstein and/or Lagrange-Finsler manifolds are transformed equivalently into spaces with generic local anisotropy induced by nonsymmetric metrics and generalized connections. We speculate on possible applications of such geometric methods in Einstein and generalized theories of gravity, analogous gravity and geometric mechanics.
Approaching Bose-Einstein Condensation
Ferrari, Loris
2011-01-01
Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial…
Einstein's Legacy, at the Globe
2005-01-01
One-hundred years on, Albert Einstein's theories continue to fuel the daily work of physicists. From research into gravity waves to the quest for grand unification in physics, today's researchers have not finished with the legacy of the most famous and iconic physicist of the 20th Century.
Galison, P L
1999-01-01
Dans la version traditionnelle de l'Histoire de la relativitÂ? restreinte,la reformulation par EINSTEIN de la simultanÂ?itÂ? est vue comme une intervention quasi-philosophique,rendue possible par le fait qu'il ait pris ses distances par rapport Â? la physique de l'Â?poque. D'autre part,l'emploi d'Einstein au Bureau des Brevets entre dans l'histoire comme un travail bassement quotidien, lui permettant une formation technique certes,mais peu pertinente pour son travail sur la relativitÂ?. Le confÂ?rencier montrera que,bien au contraire,le travail d'Einstein sur les brevets l'a placÂ? au beau milieu de trÂ?s riches discussions culturelles et de brevets menant Â? la synchronisation des horloges le long des voies de chemin de fer reliant les villes d'Europe centrale.Une fois que l'on a compris l'histoire des horloges synchronisÂ?es, le travail d'Einstein sur la relativitÂ? en mai 1905 brille d'un feu trÂ?s diffÂ?rent.
Bose-Einstein Condensation Observed
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Bose-Einstein Condensation Observed. Rajaram Nityananda. Research News Volume 1 Issue 2 February 1996 pp 111-114. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/02/0111-0114 ...
Einstein, la luz, el espacio-tiempo y los cuantos
Directory of Open Access Journals (Sweden)
Fernando Barbero G., J.
2015-10-01
Full Text Available The study of light, its nature and properties was a central topic in the works of Albert Einstein. This paper discusses the role of light in the formulation of special relativity, in particular as a tool to provide operational definitions of the basic kinematic concepts. It also discusses the role of light in understanding general relativity and ends by briefly considering its quantum behaviour.El estudio de la luz, su naturaleza y sus propiedades ocupó un lugar central en los trabajos de Albert Einstein. En este artículo se discute el papel de la luz en la formulación de la relatividad especial, en particular como instrumento para la definición operacional de las magnitudes cinemáticas básicas, se muestra su importancia para la comprensión de la relatividad general y, por último, se considera brevemente su comportamiento cuántico.
BOOK REVIEW: Once Upon Einstein
Giannetto, E.
2007-07-01
Thibault Damour is a theoretical physicist, and a member of the French Academy of Sciences. This book is the translation, by Eric Novak, of the original French Si Einstein m'etait conté (Le Cherche Midi, 2005). It is neither a book of theoretical physics nor a biography of Einstein. It is not a book of history nor philosophy of science. In Damour's words it was written to encourage the reader to share with Einstein `those times when he understood some part of the hidden order of the universe'. It is a relatively short book, written in a very fluent style, but it deals with all the major problems and achievements of Einstein's works. Starting from special relativity, it continues with general relativity, quantum theories, unified field theory and a brief overview of the actual research related to Einstein's legacy. It is essentially a popular science book with some related exploration in history and philosophy to interpret physical theories. The most important problem discussed by Damour is the nature of time. On this subject, there is a very interesting short paragraph (pp 33--35) dedicated to the reception of the relativity idea by the great writer Marcel Proust and its counterpart within À la Recherche du Temps Perdu. A correct discussion of the implications of a relativistic time should imply the distinction of the different possible interpretations of this concept. Damour seems to conclude that only one interpretation is possible: `time does not exist', flowing of time is an illusion. One has to know that Einstein's ideas on time were related to Spinoza's perspective of a knowledge sub specie aeternitatis. However, other interpretations are possible and are related to the idea of time as an actuality. Damour speaks about the controversy between Einstein and Bergson, but Bergson is considered as a philosopher who did not understand relativity. This philosophical problem of relativistic time is indeed related to a historical problem briefly discussed by Damour
Albert Einstein: Un Sionismo Pacifista Albert Einstein: Un Sionismo Pacifista
Directory of Open Access Journals (Sweden)
Francisco A. Laca Arocena
2012-02-01
Full Text Available Además del científico más conocido en el pasado siglo XX, Albert Einstein (1879-1955 fue un activo militante por el pacifismo a la vez que un nacionalista judío firme partidario de un estado para su pueblo. Con frecuencia, se contraponen el pacifismo y el nacionalismo asociando el primero a un internacionalismo incompatible con el segundo. Tras discutir algunas características del antisionismo secular en Europa, se analiza el nacionalismo judíoo sionismo como una reacción al fracaso del asimilacionismo de los judíos en la Europa Central y del Este durante la primera mitad del pasado siglo XX. Se describe en el caso de Einstein, citando textos y hechos biográfi cos, la difícil pero factible compatibilidad entre nacionalismo y pacifismo.Besides being the best-known scientist of the 20th Century, Albert Einstein (1879-1955 was an active militant for pacifism as well as a strong supporter of the idea of a Jewish state. Frequently, pacifi sm and nationalism are considered to be oposed to each other, as the first is asociated with an internationalism incompatible with the second. After discussing some features of secular anti-Zionism in Europe, Jewish nationalism or Zionism is discussed as a reaction to the failure of the Jews to be assimilated in Central and Eastern Europe during the first half of last century. In the case of Einstein, the difficult but still possible reconciliation between pacifism and nationalism is described, citing texts and biographical facts.
Albert Einstein - a Pious Atheist
Djokovic, V
2007-01-01
We consider Einstein's attitude with regard to religion both from sociological and epistemological points of view. An attempt to put it into a wider socio-historical perspective has been made, with the emphasis on his ethnic and religious background. The great scientist was neither anatheist nor a believer in the orthodox sense and the closest labels one might apply would be pantheism/cosmism (ontological view) and agnosticism (epistemological view). His ideas on the divine could be considered as a continuation of a line that can be traced back to Philo of Alexandria, who himself followed the Greek Stoics and Neoplatonists and especially Baruch Spinoza. Einstein's scientific (or rational) and religious (or intuitive) thinking was deeply rooted in the Hellenic culture.
Albert Einstein and Scientific Theology
Andrews, Max L E
2012-01-01
In recent centuries the world has become increasingly dominated by empirical evidence and theoretic science in developing worldviews. Advances in science have dictated Roman Catholic doctrine such as the acceptance of Darwinian evolution and Big Bang cosmology. Albert Einstein created an indelible impact on the relationship between science and religion. The question is whether or not his work was deleterious for church doctrine or whether it was compatible with, or even advanced, church dogma. It's my contention that Einstein revived the relationship between science and theology and did not create a bifurcation between the two. Despite his personal religious beliefs, his work has helped to reinforce the harmonious conjunction of science with religion, which cannot be ignored by succeeding scientists and theologians.
The global Utiyama theorem in Einstein-Cartan theory
Bruzzo, Ugo
1987-09-01
A global formulation of Utiyama's theorem for Einstein-Cartan-type gravitational theories regarded as gauge theories of the group of space-time diffeomorphisms is given. The local conditions for the Lagrangian to be gauge invariant coincide with those found by other authors [A. Pérez-Rendón Collantes, ``Utiyama type theorems,'' in Poincaré Gauge Approach to Gravity. I, Proceedings Journées Relativistes 1984; A. Pérez-Rendón and J. J. Seisdedos, ``Utiyama type theorems in Poincaré gauge approach to gravity. II, '' Preprints de Mathematicas, Universidad de Salamanca, 1986] in Kibble's and Hehl's approaches.
The Routledge guidebook to Einstein's relativity
Trefil, James
2015-01-01
Albert Einstein, one of the most prolific scientists of the twentieth century, developed the theory of relativity which was crucial for the advancement of modern physics. Young Einstein identified a paradox between Newtonian Mechanics and Maxwell's equations which pointed to a flawed understanding of space and time by the scientists of the day. In Relativity, Einstein presents his findings using a minimal amount of mathematical language, but the text can still be challenging for readers who lack an extensive scientific background.The Routledge Guidebook to Einstein's Relativity expands on and
Einstein's Jury The Race to Test Relativity
Crelinsten, Jeffrey
2006-01-01
Einstein's Jury is the dramatic story of how astronomers in Germany, England, and America competed to test Einstein's developing theory of relativity. Weaving a rich narrative based on extensive archival research, Jeffrey Crelinsten shows how these early scientific debates shaped cultural attitudes we hold today. The book examines Einstein's theory of general relativity through the eyes of astronomers, many of whom were not convinced of the legitimacy of Einstein's startling breakthrough. These were individuals with international reputations to uphold and benefactors and shareholders to p
Albert Einstein, un hombre universal
Arias Arroyo, Gladys
2014-01-01
Albert Einstein, famoso por su teoría de la relatividad, que cambió toda las concepciones previas sobre la gravitación, el cosmos, la geometría y en general toda la ciencia moderna. Además de ser un genio científico, fue un gran humanista, partidario de la convivencia pacífica entre los pueblos, gran defensor de la libertad individual y del progreso. A pesar de que en su infancia y juventud tropezó con más inconvenientes que ventajas, tuvo la gran habilidad de conectar sus innegables dotes na...
Jerome, Fred
2005-01-01
Nearly fifty years after his death, Albert Einstein remains one of America's foremost cultural icons. A thicket of materials, ranging from scholarly to popular, have been written, compiled, produced, and published about his life and his teachings. Among the ocean of Einsteinia-scientific monographs, biographies, anthologies, bibliographies, calendars, postcards, posters, and Hollywood films-however, there is a peculiar void when it comes to the connection that the brilliant scientist had with the African American community. Nowhere is there any mention of his close relationship with Pa
Albert Einstein:. Opportunity and Perception
Yang, Chen Ning
2013-05-01
The year 1905 has been called Albert Einstein's "Annus Mirabilis." It was during that year that he caused revolutionary changes in man's primordial concepts about the physical world: space, time, energy, light and matter. How could a 26-year-old clerk, previously unknown, cause such profound conceptual changes, and thereby open the door to the era of modern scientific technological world? No one, of course, can answer that question. But one can, perhaps, analyze some factors that were essential to his stepping into such a historic role...
New details emerge from the Einstein files
Overbye, D
2002-01-01
For many years the FBI spied on Einstein. New details of this surveilance are emerging in "The Einstein File: J. Edgar Hoover's Secret War Against the World's Most Famous Scientist," by Fred Jerome, who sued the government with the help of the Public Citizen Litigation Group to obtain a less censored version of the file (1 page).
Books on Einstein--Collectors' Delight
Khoon, Koh Aik; Jalal, Azman; Abd-Shukor, R.; Yatim, Baharudin; Talib, Ibrahim Abu; Daud, Abdul Razak; Samat, Supian
2009-01-01
A survey of thirteen books on Einstein is presented. Its gives an idea on how much is written about the man and how frequent are the publications. The year 2005 saw the most publications. It is the centenary for the Miraculous Year. Interestingly some books can just sustain their readers' interest with just words. Einstein comes alive with the…
Einstein as a Missionary of Science
Renn, Jürgen
2013-01-01
The paper reviews Einstein's engagement as a mediator and popularizer of science. It discusses the formative role of popular scientific literature for the young Einstein, showing that not only his broad scientific outlook but also his internationalist political views were shaped by these readings. Then, on the basis of recent detailed…
What Einstein Can Teach Us about Education
Hayes, Denis
2007-01-01
People are more likely to associate Einstein with complex scientific theories and mathematical calculations than with education theory. In fact, Einstein's own experiences of schooling and his reflections on the meaning of life and the significance of education are profound and oddly relevant to the situation that pertains in England today. It is…
Einstein in love a scientific romance
Overbye, Dennis
2000-01-01
At its height, Einstein's marriage to Mileva was an extraordinary one - a colleague and often fierce adversary, Mileva was brilliantly matched with the scientific genius. Dennis Overbye seeks to present this scientific romance in a vivid light, telling the private story of the young Einstein.
A student's guide to Einstein's major papers
Kennedy, Robert E
2012-01-01
Our understanding of the physical universe underwent a revolution in the early twentieth century - evolving from the classical physics of Newton, Galileo, and Maxwell to the modern physics of relativity and quantum mechanics. The dominant figure in this revolutionary change was Albert Einstein. In a single year, 1905, Einstein produced breakthrough works in three areas of physics: on the size and the effects of atoms; on the quantization of the electromagnetic field; and on the special theory of relativity. In 1916 he produced a fourth breakthrough work, the general theory of relativity. A Student's Guide to Einstein's Major Papers focuses on Einstein's contributions, setting his major works into their historical context, and then takes the reader through the details of each paper, including the mathematics. This book helps the reader appreciate the simplicity and insightfulness of Einstein's ideas and how revolutionary his work was, and locate it in the evolution of scientific thought begun by the ancient...
Einstein a hundred years of relativity
Robinson, Andrew
2015-01-01
"The eternal mystery of the world is its comprehensibility … The fact that it is comprehensible is a miracle." --Albert Einstein, 1936 Albert Einstein's universal appeal is only partially explained by his brilliant work in physics, as Andrew Robinson demonstrates in this authoritative, accessible, and richly illustrated biography. The main narrative is enriched by twelve essays by well-known scientists, scholars, and artists, including three Nobel Laureates. The book presents clearly the beautiful simplicity at the heart of Einstein's greatest discoveries, and explains how his ideas have continued to influence scientific developments such as lasers, the theory of the big bang, and "theories of everything." Einstein's life and activities outside of science are also considered, including his encounters with famous contemporaries such as Chaplin, Roosevelt, and Tagore, his love of music, and his troubled family life. The book recognizes that Einstein's striking originality was expressed in many ways, from hi...
Albert Einstein's Magic Mountain: An Aarau Education*
Hunziker, Herbert
2015-03-01
For economic reasons, the electrotechnical factory J. Einstein & Cie. (co-owned by Albert Einstein's father Hermann) had to be closed in the summer of 1894. While Albert's parents emigrated to Italy to build a new existence, he remained in Munich to complete his studies at the Gymnasium. Left behind, however, he had a difficult time with what he considered the rigid educational practices at the Munich Luitpold-Gymnasium and quit without a diploma. The present article discusses Einstein's richly winding path to the Aargau Cantonal School (Switzerland), especially its history and educational philosophy during the time of his stay in Aarau. There, Einstein met some outstanding teachers, who could serve him as models of scholars and human beings. In spite of Einstein's distinct independence of mind, these personalities may well have had a significant influence on the alignment of his inner compass.
Albert Einstein, cosmos and religion
Directory of Open Access Journals (Sweden)
Doković V.
2007-01-01
Full Text Available We consider Einstein's attitude regarding religious as such, from both cosmological and epistemological points of view. An attempt to put it into a wider socio-historical perspective was made, with the emphasis on ethnic and religious background. It turns out that the great scientist was neither atheist nor believer in the orthodox sense and the closest labels one might stick to him in this respect would be pantheism/cosmism (ontological aspect and agnosticism (epistemological aspect. His ideas on divine could be considered as a continuation of line traced by Philo of Alexandria, who himself followed Greek Stoics and (Neo- Platonists and especially Baruch Spinoza. It turns out that Einstein's both scientific (rational aspects and religious (intuitive aspects thinking were deeply rooted in the Hellenic culture. His striving to unravel the secrets of the universe and the roots of cosmological order resembles much the ancient ideas of the role of knowledge in fathoming the divine as such, as ascribed to Gnostics. .
Einstein's daughter the search for Lieserl
Zackheim, Michele
1999-01-01
A thoroughly gripping and groundbreaking investigation into the mysterious fate of Albert Einstein's illegitimate daughter. Albert Einstein fell in love with Mileva Maric, the woman who would become his first wife, when they were students at the Zurich Polytechnic Institute. When Maric conceived a child out of wedlock, she went home to her family in Serbia to have the child. Lieserl Maric Einstein was born in 1902. Though Einstein and Maric married the following year, Lieserl was left in the care of her grandparents and never became a part of the Einstein family. In fact, her very existence was unknown until the recent discovery of a cache of letters between Einstein and Maric. The final reference to Lieserl comes in a September 1903 letter, when, at the age of approximately eighteen months, she simply disappears. What happened to Einstein's daughter is the most potent mystery to emerge from the mythology that surrounds one of the century's legendary figures, owing in large part to the careful and apparent...
Correct Linearization of Einstein's Equations
Directory of Open Access Journals (Sweden)
Rabounski D.
2006-04-01
Full Text Available Routinely, Einstein’s equations are be reduced to a wave form (linearly independent of the second derivatives of the space metric in the absence of gravitation, the space rotation and Christoffel’s symbols. As shown herein, the origin of the problem is the use of the general covariant theory of measurement. Herein the wave form of Einstein’s equations is obtained in terms of Zelmanov’s chronometric invariants (physically observable projections on the observer’s time line and spatial section. The equations so obtained depend solely upon the second derivatives, even for gravitation, the space rotation and Christoffel’s symbols. The correct linearization proves that the Einstein equations are completely compatible with weak waves of the metric.
Entanglement Equilibrium and the Einstein Equation.
Jacobson, Ted
2016-05-20
A link between the semiclassical Einstein equation and a maximal vacuum entanglement hypothesis is established. The hypothesis asserts that entanglement entropy in small geodesic balls is maximized at fixed volume in a locally maximally symmetric vacuum state of geometry and quantum fields. A qualitative argument suggests that the Einstein equation implies the validity of the hypothesis. A more precise argument shows that, for first-order variations of the local vacuum state of conformal quantum fields, the vacuum entanglement is stationary if and only if the Einstein equation holds. For nonconformal fields, the same conclusion follows modulo a conjecture about the variation of entanglement entropy.
Einstein wrote back my life in physics
Moffat, John W
2012-01-01
John W. Moffat was a poor student of math and science. That is, until he read Einstein's famous paper on general relativity. Realizing instantly that he had an unusual and unexplained aptitude for understanding the complex physics described in the paper, Moffat wrote a letter to Einstein that would change the course of his life. Einstein Wrote Back tells the story of Moffat's unusual entry into the world of academia and documents his career at the frontlines of twentieth-century physics as he worked and associated with some of the greatest minds in scientific history, including Niels Bohr,
Oberheim, Eric
2016-06-01
Thomas Kuhn and Paul Feyerabend promote incommensurability as a central component of their conflicting accounts of the nature of science. This paper argues that in so doing, they both develop Albert Einstein's views, albeit in different directions. Einstein describes scientific revolutions as conceptual replacements, not mere revisions, endorsing 'Kant-on-wheels' metaphysics in light of 'world change'. Einstein emphasizes underdetermination of theory by evidence, rational disagreement in theory choice, and the non-neutrality of empirical evidence. Einstein even uses the term 'incommensurable' specifically to apply to challenges posed to comparatively evaluating scientific theories in 1949, more than a decade before Kuhn and Feyerabend. This analysis shows how Einstein anticipates substantial components of Kuhn and Feyerabend's views, and suggests that there are strong reasons to suspect that Kuhn and Feyerabend were directly inspired by Einstein's use of the term 'incommensurable', as well as his more general methodological and philosophical reflections. Copyright © 2015 Elsevier Ltd. All rights reserved.
How History Helped Einstein in Special Relativity
Martinez, Alberto
2013-04-01
I will discuss how the German intellectual movement known as ``critical history'' motivated several physicists in the late 1900s to radically analyze the fundamental principles of mechanics, leading eventually to Einstein's special theory of relativity. Eugen Karl Dühring, Johann Bernhard Stallo, Ludwig Lange, and Ernst Mach wrote critical histories of mechanics, some of which emphasized notions of relativity and observation, in opposition to old metaphysical concepts that seemed to infect the foundations of physics. This strand of critical history included the ``genetic method'' of analyzing how concepts develop over time, in our minds, by way of ordinary experiences, which by 1904 was young Albert Einstein's favorite approach for examining fundamental notions. Thus I will discuss how history contributed in Einstein's path to relativity, as well as comment more generally on Einstein's views on history.
Universal Themes of Bose-Einstein Condensation
Proukakis, Nick P.; Snoke, David W.; Littlewood, Peter B.
2017-04-01
Foreword; List of contributors; Preface; Part I. Introduction: 1. Universality and Bose-Einstein condensation: perspectives on recent work D. W. Snoke, N. P. Proukakis, T. Giamarchi and P. B. Littlewood; 2. A history of Bose-Einstein condensation of atomic hydrogen T. Greytak and D. Kleppner; 3. Twenty years of atomic quantum gases: 1995-2015 W. Ketterle; 4. Introduction to polariton condensation P. B. Littlewood and A. Edelman; Part II. General Topics: Editorial notes; 5. The question of spontaneous symmetry breaking in condensates D. W. Snoke and A. J. Daley; 6. Effects of interactions on Bose-Einstein condensation R. P. Smith; 7. Formation of Bose-Einstein condensates M. J. Davis, T. M. Wright, T. Gasenzer, S. A. Gardiner and N. P. Proukakis; 8. Quenches, relaxation and pre-thermalization in an isolated quantum system T. Langen and J. Schmiedmayer; 9. Ultracold gases with intrinsic scale invariance C. Chin; 10. Berezinskii-Kosterlitz-Thouless phase of a driven-dissipative condensate N. Y. Kim, W. H. Nitsche and Y. Yamamoto; 11. Superfluidity and phase correlations of driven dissipative condensates J. Keeling, L. M. Sieberer, E. Altman, L. Chen, S. Diehl and J. Toner; 12. BEC to BCS crossover from superconductors to polaritons A. Edelman and P. B. Littlewood; Part III. Condensates in Atomic Physics: Editorial notes; 13. Probing and controlling strongly correlated quantum many-body systems using ultracold quantum gases I. Bloch; 14. Preparing and probing chern bands with cold atoms N. Goldman, N. R. Cooper and J. Dalibard; 15. Bose-Einstein condensates in artificial gauge fields L. J. LeBlanc and I. B. Spielman; 16. Second sound in ultracold atomic gases L. Pitaevskii and S. Stringari; 17. Quantum turbulence in atomic Bose-Einstein condensates N. G. Parker, A. J. Allen, C. F. Barenghi and N. P. Proukakis; 18. Spinor-dipolar aspects of Bose-Einstein condensation M. Ueda; Part IV. Condensates in Condensed Matter Physics: Editorial notes; 19. Bose-Einstein
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)
Solitons in Bose–Einstein condensates
Indian Academy of Sciences (India)
function interaction. Keywords. Solitons .... where Tc is the Bose–Einstein condensation temperature, the bosons are normal so that 〈 〉 vanishes. ... solutions. Small deviations around the background density ρ0 are studied by setting ψ(r, t) = √.
Recent developments in Bose-Einstein condensation
Energy Technology Data Exchange (ETDEWEB)
Kalman, G.
1997-09-22
This paper contains viewgraphs on developments on Bose-Einstein condensation. Some topics covered are: strongly coupled coulomb systems; standard response functions of the first and second kind; dynamical mean field theory; quasi localized charge approximation; and the main equations.
String Theory has Einstein's dream come true?
CERN. Geneva
2005-01-01
After having outlined the difficulties that Einstein and others have encountered in trying to unify our understanding of macroscopic/classical and microscopic /quantum physics, I will explain in simple terms how the latest particle theory revolution, string theory, may finally offer a surprisingly simple realization of these long-standing dreams. Einstein thought that his difficulties stemmed from a clash between the classical and the quantum. Yet, paradoxically, superstrings appear to realize his dream thanks to -and not against- quantum mechanics.
Newton to Einstein - dust to dust
Kopp, Michael; Uhlemann, Cora; Haugg, Thomas
2013-01-01
We investigate the relation between the standard Newtonian equations for a pressureless fluid (dust) and the Einstein equations in a double expansion in small scales and small metric perturbations. We find that parts of the Einstein equations can be rewritten as a closed system of two coupled differential equations for the scalar and transverse vector metric perturbations in Poisson gauge. It is then shown that this system is equivalent to the Newtonian system of continuity and Euler equation...
Einstein and Gravitational Waves 1936-1938
Weinstein, Galina
2016-01-01
Around 1936, Einstein wrote to his close friend Max Born telling him that, together with Nathan Rosen, he had arrived at the interesting result that gravitational waves did not exist, though they had been assumed a certainty to the first approximation. He finally had found a mistake in his 1936 paper with Rosen and believed that gravitational waves do exist. However, in 1938, Einstein again obtained the result that there could be no gravitational waves!
Einstein before Israel Zionist icon or iconoclast?
Rosenkranz, Ze’ev
2011-01-01
Albert Einstein was initially skeptical and even disdainful of the Zionist movement, yet he affiliated himself with this controversial political ideology and today is widely seen as an outspoken advocate for a modern Jewish homeland in Palestine. What enticed this renowned scientist and humanitarian, who repeatedly condemned nationalism of all forms, to radically change his views? Was he in fact a Zionist? Einstein Before Israel traces Einstein's involvement with Zionism from his initial contacts with the movement at the end of World War I to his emigration from Germany in 1933 in the wake of Hitler's rise to power. Drawing on a wealth of rare archival evidence--much of it never before published--this book offers the most nuanced picture yet of Einstein's complex and sometimes stormy relationship with Jewish nationalism. Ze'ev Rosenkranz sheds new light on Einstein's encounters with prominent Zionist leaders, and reveals exactly what Einstein did and didn't like about Zionist beliefs, objectives, and methods...
The practical Einstein experiments, patents, inventions
Illy, József
2012-01-01
Albert Einstein may be best known as the wire-haired whacky physicist who gave us the theory of relativity, but that's just one facet of this genius' contribution to human knowledge and modern science. As Jozsef Illy expertly shows in this book, Einstein had an eminently practical side as well. As a youth, Einstein was an inveterate tinkerer in the electrical supply factory his father and uncle owned and operated. His first paid job was as a patent examiner. Later in life, Einstein contributed to many inventions, including refrigerators, microphones, and instruments for aviation. In published papers, Einstein often provided ways to test his theories and fundamental problems of the scientific community of his times. He delved deeply into a variety of technological innovations, most notably the gyrocompass, and consulted for industry in patent cases and on other legal matters. Einstein also provided explanations for common and mundane phenomena, such as the meandering of rivers. In these and other hands-on exam...
Dirac's and Generalized Faddeev-Jackiw brackets for Einstein's theory in G $\\rightarrow 0$ limit
Escalante, Alberto; Rodríguez-Tzompantzi, Omar
2015-01-01
In this paper the Dirac and Faddeev-Jackiw formulation for Einstein's theory in the $G \\rightarrow 0$ limit is performed; the fundamental Dirac's and Faddeev-Jackiw brackets for the theory are obtained. First, the Dirac brackets are constructed by eliminating the second class constraints remaining the first class ones, then we fix the gauge and we convert the first class constraints into second class constraints and the new fundamental Dirac's brackets are computed. Alternatively, we reproduc...
Sterken, C.; Duerbeck, H. W.; Dick, W. R.
2006-12-01
This book collects about 15 papers (most of them by one single author) on Einstein and the history of general relativity (GR) and the foundations of relativistic cosmology. The matter not only deals with Einstein and his times, but also with pre-GR ideas, and with the interplay of Einstein and his colleagues (opposing as well as supporting personalities). As the title indicates, all papers are written in German, but they include comprehensive Abstracts both in German and English. The book is illustrated with quite a number classical - but also some far more original though not less beautiful - photographs and facsimiles of documents. The book is edited very well, though the style of references is not quite homogeneous. There is no Index. K. Hentschel covers Einstein's argumentation for the existence of graviational redshift, and the initial search for empirical support. The error analysis of observational evidence supporting relativistic light deflection is discussed in a paper by P. Brosche. In particular, H. Duerbeck and P. Flin - in their description of the life and work of Silberstein, who was quite sceptic on the significance of the observational verifications a la Eddington - include the transcription of two most revealing letters by Silberstein to Sommerfeld (1919) and to Einstein (1934). In the first letter, Silberstein clearly shows his scientific maturity and integrity by scrutinising the observational evidence supporting light deflection, presented at a joint meeting of the Royal Society and the Royal Astronomical Society. The second letter, which is more a personal letter, includes lots of political references and connotations. Some of Einstein's political views are also revealed by D.B. Herrmann on the basis of his own correspondence with E.G. Straus, a collaborator of Einstein's. In a consequent paper, S. Grundmann gives remarks on Herrmann's contribution and illustrates Einstein's attitude towards Marx, Engels, Lenin and Stalin. M. Schemmel discusses
The Adolescence of Relativity: Einstein, Minkowski, and the Philosophy of Space and Time
Dieks, Dennis
An often repeated account of the genesis of special relativity tells us that relativity theory was to a considerable extent the fruit of an operationalist philosophy of science. Indeed, Einstein's 1905 paper stresses the importance of rods and clocks for giving concrete physical content to spatial and temporal notions. I argue, however, that it would be a mistake to read too much into this. Einstein's operationalist remarks should be seen as serving rhetoric purposes rather than as attempts to promulgate a particular philosophical position - in fact, Einstein never came close to operationalism in any of his philosophical writings. By focussing on what could actually be measured with rods and clocks Einstein shed doubt on the empirical status of a number of pre-relativistic concepts, with the intention to persuade his readers that the applicability of these concepts was not obvious. This rhetoric manoeuvre has not always been rightly appreciated in the philosophy of physics. Thus, the influence of operationalist misinterpretations, according to which associated operations strictly define what a concept means, can still be felt in present-day discussions about the conventionality of simultaneity.The standard story continues by pointing out that Minkowski in 1908 supplanted Einstein's approach with a realist spacetime account that has no room for a foundational role of rods and clocks: relativity theory became a description of a four-dimensional "absolute world." As it turns out, however, it is not at all clear that Minkowski was proposing a substantivalist position with respect to spacetime. On the contrary, it seems that from a philosophical point of view Minkowski's general position was not very unlike the one in the back of Einstein's mind. However, in Minkowski's formulation of special relativity it becomes more explicit that the content of spatiotemporal concepts relates to considerations about the form of physical laws. If accepted, this position has important
Einstein's Theory Fights off Challengers
2010-04-01
Two new and independent studies have put Einstein's General Theory of Relativity to the test like never before. These results, made using NASA's Chandra X-ray Observatory, show Einstein's theory is still the best game in town. Each team of scientists took advantage of extensive Chandra observations of galaxy clusters, the largest objects in the Universe bound together by gravity. One result undercuts a rival gravity model to General Relativity, while the other shows that Einstein's theory works over a vast range of times and distances across the cosmos. The first finding significantly weakens a competitor to General Relativity known as "f(R) gravity". "If General Relativity were the heavyweight boxing champion, this other theory was hoping to be the upstart contender," said Fabian Schmidt of the California Institute of Technology in Pasadena, who led the study. "Our work shows that the chances of its upsetting the champ are very slim." In recent years, physicists have turned their attention to competing theories to General Relativity as a possible explanation for the accelerated expansion of the universe. Currently, the most popular explanation for the acceleration is the so-called cosmological constant, which can be understood as energy that exists in empty space. This energy is referred to as dark energy to emphasize that it cannot be directly detected. In the f(R) theory, the cosmic acceleration comes not from an exotic form of energy but from a modification of the gravitational force. The modified force also affects the rate at which small enhancements of matter can grow over the eons to become massive clusters of galaxies, opening up the possibility of a sensitive test of the theory. Schmidt and colleagues used mass estimates of 49 galaxy clusters in the local universe from Chandra observations, and compared them with theoretical model predictions and studies of supernovas, the cosmic microwave background, and the large-scale distribution of galaxies. They
Approaching Bose-Einstein condensation
Energy Technology Data Exchange (ETDEWEB)
Ferrari, Loris, E-mail: loris.ferrari@unibo.it [Department of Physics of the University, Viale B. Pichat, 6/2, 40127, Bologna (Italy)
2011-11-15
Bose-Einstein condensation (BEC) is discussed at the level of an advanced course of statistical thermodynamics, clarifying some formal and physical aspects that are usually not covered by the standard pedagogical literature. The non-conventional approach adopted starts by showing that the continuum limit, in certain cases, cancels out the crucial role of the bosonic ground level. If so, a correct treatment of the problem, including the ground level population N{sub 0} by construction, leads to BEC in a straightforward way. For a density of states of the form G({epsilon}){approx}{epsilon}{sup {gamma}}, the chemical potential {mu} is explicitly calculated as a function of the temperature T and of the number N of bosons, for various significant values of the positive exponent {gamma}. In the thermodynamic limit, in which the boson number N diverges and BEC is a sharp process, the chemical potential {mu} is a singular function of T at the critical temperature T{sub B}, determined by an appropriate critical exponent. The condensate population N{sub 0} is studied analytically and numerically as a function of the temperature, for various values of N and for different {gamma}. This provides an accurate description of the way BEC approaches the character of a sharp phase transition. Some aspects of the real experiments on BEC, involving a finite number of bosons, are also illustrated.
Focus on quantum Einstein gravity Focus on quantum Einstein gravity
Ambjorn, Jan; Reuter, Martin; Saueressig, Frank
2012-09-01
The gravitational asymptotic safety program summarizes the attempts to construct a consistent and predictive quantum theory of gravity within Wilson's generalized framework of renormalization. Its key ingredient is a non-Gaussian fixed point of the renormalization group flow which controls the behavior of the theory at trans-Planckian energies and renders gravity safe from unphysical divergences. Provided that the fixed point comes with a finite number of ultraviolet-attractive (relevant) directions, this construction gives rise to a consistent quantum field theory which is as predictive as an ordinary, perturbatively renormalizable one. This opens up the exciting possibility of establishing quantum Einstein gravity as a fundamental theory of gravity, without introducing supersymmetry or extra dimensions, and solely based on quantization techniques that are known to work well for the other fundamental forces of nature. While the idea of gravity being asymptotically safe was proposed by Steven Weinberg more than 30 years ago [1], the technical tools for investigating this scenario only emerged during the last decade. Here a key role is played by the exact functional renormalization group equation for gravity, which allows the construction of non-perturbative approximate solutions for the RG-flow of the gravitational couplings. Most remarkably, all solutions constructed to date exhibit a suitable non-Gaussian fixed point, lending strong support to the asymptotic safety conjecture. Moreover, the functional renormalization group also provides indications that the central idea of a non-Gaussian fixed point providing a safe ultraviolet completion also carries over to more realistic scenarios where gravity is coupled to a suitable matter sector like the standard model. These theoretical successes also triggered a wealth of studies focusing on the consequences of asymptotic safety in a wide range of phenomenological applications covering the physics of black holes, early
The Early life of Albert Einstein: Seeking the Mature Einstein in his ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 9. The Early Life of Albert Einstein: Seeking the Mature Einstein in his Youth. Kamal Datta. Reflections Volume 10 Issue 9 September 2005 pp 85-96. Fulltext. Click here to view fulltext PDF. Permanent link:
Gauges and functional measures in quantum gravity I: Einstein theory
Energy Technology Data Exchange (ETDEWEB)
Ohta, N. [Department of Physics, Kindai University,Higashi-Osaka, Osaka 577-8502 (Japan); Percacci, R. [International School for Advanced Studies,via Bonomea 265, 34136 Trieste (Italy); INFN, Sezione di Trieste,Trieste (Italy); Pereira, A.D. [International School for Advanced Studies,via Bonomea 265, 34136 Trieste (Italy); Universidade Federal Fluminense, Instituto de Física, Campus da Praia Vermelha, Avenida General Milton Tavares de Souza s/n, 24210-346, Niterói, RJ (Brazil); Max Planck Institute for Gravitational Physics (Albert Einstein Institute),Am Mühlenberg 1, Potsdam 14476 (Germany)
2016-06-20
We perform a general computation of the off-shell one-loop divergences in Einstein gravity, in a two-parameter family of path integral measures, corresponding to different ways of parametrizing the graviton field, and a two-parameter family of gauges. Trying to reduce the gauge- and measure-dependence selects certain classes of measures and gauges respectively. There is a choice of two parameters (corresponding to the exponential parametrization and the partial gauge condition that the quantum field be traceless) that automatically eliminates the dependence on the remaining two parameters and on the cosmological constant. We observe that the divergences are invariant under a Z{sub 2} “duality” transformation that (in a particularly important special case) involves the replacement of the densitized metric by a densitized inverse metric as the fundamental quantum variable. This singles out a formulation of unimodular gravity as the unique “self-dual” theory in this class.
Secrets of the old one Einstein, 1905
Bernstein, Jeremy
2006-01-01
In March 1905, at approximately eight week intervals, the Editor of the noted German physics journal, Annalen der Physik, received three hand-written manuscripts from a relatively unknown patent examiner in Bern, Switzerland. This patent examiner was the twenty-six year old Albert Einstein and the three papers would set the agenda for twentieth century physics. A fourth short paper was received in September 1905 and contained Einstein's derivation of the formula E=mc^2. These papers changed our lives in the twentieth century and beyond. While to a professional physicist the mathematics in these papers are quite straight forward, the ideas behind them are not. In fact, none of Einstein's contemporaries fully understood what he had done. In SECRETS OF THE OLD ONE: Einstein, 1905, renowned science writer Jeremy Bernstein makes these ideas accessible to a general reader with a limited background in mathematics. After reading this book, you will understand why 1905 is often designated as Einstein's miracle year.
Role of spacetime boundaries in a vierbein formulation of gravity
Oshita, Naritaka; Wu, Yi-Peng
2017-08-01
Einstein's vierbein formulation of general relativity based on the notion of distant parallelism (teleparallelism) naturally introduces a covariant surface term in addition to the Einstein-Hilbert action. We investigate the action principle in teleparallelism with the existence of spacetime boundaries and find that the covariant surface term exactly eliminates all the unwanted surface terms that reside in the metric formulation of general relativity, in the role of a Gibbons-Hawking-York (GHY) term. The identity of such a covariant GHY term is further confirmed by the recovery of the correct black hole entropy from the free energy due to the spacetime boundary. These results indicate that the vierbein formulation of gravity generally exhibits a well-posed action principle and readily admits the path-integral approach to quantization.
De Sitter en Einstein. ‘Het lijkt mij dat Einstein hier een vergissing begaan heeft’
Directory of Open Access Journals (Sweden)
Jan Guichelaar
2016-10-01
Full Text Available De Sitter and EinsteinWillem de Sitter’s interest in gravity was based on his work on celestial mechanics, in particular on the four big moons of Jupiter. His work on cosmology was based on the general theory of relativity of Albert Einstein. De Sitter published in 1917, on request of Arthur Eddington to inform the English astronomers, a series of four articles in The Observatory and the Monthly Notices of the Royal Astronomical Society. Einstein developed his own cosmological models, containing mass. De Sitter found a different solution and described a universe without mass. Einstein could not accept De Sitter’s model and they ‘fought out’ two controversies in their correspondence. In theend Einstein had to confess De Sitter was mainly right in his criticisms. In 1932 Einstein and De Sitter published an article on a new model, the so-called Einstein-De Sitter Model of the universe. So, De Sitter was able to do fundamental work in classical celestial mechanics as well as in the new cosmological theories.
How Einstein Got His Field Equations
Walters, Sam
2016-01-01
We study the pages in Albert Einstein's 1916 landmark paper in the Annalen der Physik where he derived his field equations for gravity. Einstein made two heuristic and physically insightful steps. The first was to obtain the field equations in vacuum in a rather geometric fashion. The second step was obtaining the field equations in the presence of matter from the field equations in vacuum. (This transition is an essential principle in physics, much as the principle of local gauge invariance in quantum field theory.) To this end, we go over some quick differential geometric background related to curvilinear coordinates, vectors, tensors, metric tensor, Christoffel symbols, Riemann curvature tensor, Ricci tensor, and see how Einstein used geometry to model gravity.
Einstein, Ethics and the Atomic Bomb
Rife, Patricia
2005-03-01
Einstein voiced his ethical views against war as well as fascism via venues and alliances with a variety of organizations still debated today. In 1939, he signed a letter to President Roosevelt (drafted by younger colleagues Szilard, Wigner and others) warning the U.S.government about the danger of Nazi Germany gaining control of uranium in the Belgian-controlled Congo in order to develop atomic weapons, based on the discovery of fission by Otto Hahn and Lise Meitner. In 1945, he became a member of the Princeton-based ``Emergency Committee for Atomic Scientists'' organized by Bethe, Condon, Bacher, Urey, Szilard and Weisskopf. Rare Einstein slides will illustrate Dr.Rife's presentation on Albert Einstein's philosophic and ethical convictions about peace, and public stance against war (1914-1950).
PBR theorem and Einstein's quantum hole argument
Weinstein, Galina
2013-01-01
This note discusses the latest hot topic: Quantum states: ontic or epistemic? and the PBR theorem. Upon reading Einstein's views on quantum incompleteness in publications or in his correspondence after 1935 (the EPR paradox), one gets a very intense feeling of deja-vu. Einstein presents a quantum hole argument, which somewhat reminds of the hole argument in his 1914 "Entwurf" general theory of relativity. In their paper, PBR write the following: "an important step towards the derivation of our result is the idea that the quantum state is physical if distinct quantum states correspond to non-overlapping distributions for [the set of possible physical states that a system can be in]", and they then refer to Einstein's argument and views.
Bose-Einstein condensation in microgravity.
van Zoest, T; Gaaloul, N; Singh, Y; Ahlers, H; Herr, W; Seidel, S T; Ertmer, W; Rasel, E; Eckart, M; Kajari, E; Arnold, S; Nandi, G; Schleich, W P; Walser, R; Vogel, A; Sengstock, K; Bongs, K; Lewoczko-Adamczyk, W; Schiemangk, M; Schuldt, T; Peters, A; Könemann, T; Müntinga, H; Lämmerzahl, C; Dittus, H; Steinmetz, T; Hänsch, T W; Reichel, J
2010-06-18
Albert Einstein's insight that it is impossible to distinguish a local experiment in a "freely falling elevator" from one in free space led to the development of the theory of general relativity. The wave nature of matter manifests itself in a striking way in Bose-Einstein condensates, where millions of atoms lose their identity and can be described by a single macroscopic wave function. We combine these two topics and report the preparation and observation of a Bose-Einstein condensate during free fall in a 146-meter-tall evacuated drop tower. During the expansion over 1 second, the atoms form a giant coherent matter wave that is delocalized on a millimeter scale, which represents a promising source for matter-wave interferometry to test the universality of free fall with quantum matter.
Theoretical Investigations of Trapped Interacting Bose-Einstein Condensates
National Research Council Canada - National Science Library
You, Li
1999-01-01
.... Primary topics being addressed are: (1) To understand the properties of atomic Bose-Einstein condensates, in particular, the low energy excitations, dynamics of Bose-Einstein condensation, vortex states creation and detection. (2...
Coherence, Abstraction, and Personal Involvement: Albert Einstein, Physicist and Humanist.
Ne'eman, Yuval
1979-01-01
Reviews Einstein's main contributions to physics, and analyzes the importance of a coherent body of theory. Einstein's involvement in nonscientific issues such as nuclear disarmament is also included. (HM)
Einstein's enigma or black holes in my bubble bath
Vishveshwara, C V
2006-01-01
A funny rendition of the story of gravitation theory from the early historic origins to the developments in astrophysics, focusing on Albert Einstein''s theory of general relativity and black-hole physics.
Beyond Einstein: Exploring the Extreme Universe
Barbier, Louis M.
2005-01-01
This paper will give an overview of the NASA Universe Division Beyond Einstein program. The Beyond Einstein program consists of a series of exploratory missions to investigate some of the most important and pressing problems in modern-day astrophysics - including searches for Dark Energy and studies of the earliest times in the universe, during the inflationary period after the Big Bang. A variety of new technologies are being developed both in the science instrumentation these missions will carry and in the spacecraft that will carry those instruments.
Bohr vs. Einstein: Fortolkning af kvantemekanikken
DEFF Research Database (Denmark)
Andersen, Christian Kraglund; Wade, Andrew Christopher James
2013-01-01
Siden 1913, da Bohr fremlagde sin kvantemekaniske model for atomet, har fysikere diskuteret, hvordan kvan- temekanikken skal fortolkes. Specielt aktive i denne diskussion var Bohr og Einstein, som havde modstridende opfattelser af, hvordan kvantemekanikken skulle forstås. Kan katte være både...... levende og døde på samme tid? Kan vi teleportere partikler mellem Månen og Jorden? Disse spørgsmål, og mange flere, forsøgte Bohr og Einstein at besvare, og det vil vi ligeledes i denne artikel....
Einstein une biographie dessinée
Maier, Corinne
2015-01-01
« Je m'appelle Albert Einstein. En voulant comprendre l'univers, j'ai libéré des forces de destruction terrifiantes. Mais il faut continuer à chercher le grand secret du cosmos. » Albert Einstein (1879-1955) est un immense génie devenu, sans le vouloir, une star de la science. Avec ses théories de la relativité restreinte puis de la relativité générale, il a radicalement transformé nos vies. Voici le récit de son existence passionnée et de ses contributions fondamentales.
Hypermass generalization of Einstein's gravitation theory
Edmonds, J. D., Jr.
1973-01-01
The curvilinear invariant quaternion formalism is examined for curved space time. Einstein's gravitation equation is shown to have a simple and natural form in this notation. The hypermass generalization of particle mass, which was generated in our studies of the Dirac equation, is incorporated in gravitation by generalizing Einstein's equation. Covariance requires that the gravitational constant be generalized to an invariant quaternion when the mass is. The modification appears minor and of no importance cosmologically, unless one begins considering time and mass dependence of G.
Conceptual Development of Einstein's Mass-Energy Relationship
Wong, Chee Leong; Yap, Kueh Chin
2005-01-01
Einstein's special theory of relativity was published in 1905. It stands as one of the greatest intellectual achievements in the history of human thought. Einstein described the equivalence of mass and energy as "the most important upshot of the special theory of relativity" (Einstein, 1919). In this paper, we will discuss the evolution of the…
Einstein 1905-1955: His Approach to Physics
Damour, Thibault
We review Einstein's epistemological conceptions, and indicate their philosophical roots. The particular importance of the ideas of Hume, Kant, Mach, and Poincaré is highlighted. The specific characteristics of Einstein's approach to physics are underlined. Lastly, we consider the practical application of Einstein's methodological principles to the two theories of relativity, and to quantum theory. We emphasize a Kantian approach to quantum theory.
Die Leben Einsteins eine Reise durch die Geschichte der Physik
Fiami
2005-01-01
Jeder kennt die Namen Einstein, Newton oder Galilei. aber was weiss man über sie? Hier ein Porträt Einsteins anhand von sechs Meilensteinen aus der Geschichte der Physik. Einstein tritt auf als Protagonist in verschiedenen Epochen und bei verschiedenen Entdeckungen, die die Welt verändert haben.
Invariant Einstein metrics on Ledger-Obata spaces
Chen, Zhiqi; Nikonorov, Yuriĭ; Nikonorova, Yulia
2016-01-01
In this paper, we study invariant Einstein metrics on Ledger-Obata spaces $F^m/\\operatorname{diag}(F)$. In particular, we classify invariant Einstein metrics on $F^4/\\operatorname{diag}(F)$ and estimate the number of invariant Einstein metrics on general Ledger-Obata spaces $F^{m}/\\operatorname{diag}(F)$.
Einstein e il Rinnovamento delle Scienze (Einstein and the Renewal of Science)
Recami, Erasmo
2007-01-01
As it is well-known, the year 2005 has been the centenary of the "annus mirabilis" (1905) during which Albert Einstein published four fundamental papers of his. But already in 1979, for the centenary of Einstein's birth, the world celebrated his monumantal work. In Italy too, there appeared scientific books, and many semi-popularization (or popularization) articles. The present paper represents a talk delivered in Italian, at the invitation of the Nobel Foundation (Sanremo, IM; Italy), in tim...
Bose-Einstein condensation in quantum glasses.
Carleo, Giuseppe; Tarzia, Marco; Zamponi, Francesco
2009-11-20
The role of geometrical frustration in strongly interacting bosonic systems is studied with a combined numerical and analytical approach. We demonstrate the existence of a novel quantum phase featuring both Bose-Einstein condensation and spin-glass behavior. The differences between such a phase and the otherwise insulating "Bose glasses" are elucidated.
Quantum Einstein's equations and constraints algebra
Indian Academy of Sciences (India)
In this paper we shall address this problem: Is quantum gravity constraints algebra closed and what are the quantum Einstein's equations. ... Physics Department, Iran University of Science and Technology, P.O. Box 16765-163, Narmak, Tehran, Iran; Institute for Studies in Theoretical Physics and Mathematics, P.O. Box ...
The reluctant father of black holes [Einstein].
Bernstein, J.
1996-06-01
Albert Einstein's equations of gravity are the foundation of the modern view of black holes; ironically, he used the equations in trying to prove these objects cannot exist. The author discusses quantum statistics, white dwarfs and black holes outlining the work of the key protagonists.
Einstein Slew Survey: Data analysis innovations
Elvis, Martin S.; Plummer, David; Schachter, Jonathan F.; Fabbiano, G.
1992-01-01
Several new methods were needed in order to make the Einstein Slew X-ray Sky Survey. The innovations which enabled the Slew Survey to be done are summarized. These methods included experimental approach to large projects, parallel processing on a LAN, percolation source detection, minimum action identifications, and rapid dissemination of the whole data base.
The Einstein All-Sky Slew Survey
Elvis, Martin S.
1992-01-01
The First Einstein IPC Slew Survey produced a list of 819 x-ray sources, with f(sub x) approximately 10(exp -12) - 10(exp -10) erg/sq cm s and positional accuracy of approximately 1.2 feet (90 percent radius). The aim of this program was to identify these x-ray sources.
[Albert Einstein and his abdominal aortic aneurysm].
Cervantes Castro, Jorge
2011-01-01
The interesting case of Albert Einstein's abdominal aortic aneurysm is presented. He was operated on at age 69 and, finding that the large aneurysm could not be removed, the surgeon elected to wrap it with cellophane to prevent its growth. However, seven years later the aneurysm ruptured and caused the death of the famous scientist.
Einstein Observations of Galactic supernova remnants
Seward, Frederick D.
1990-01-01
This paper summarizes the observations of Galactic supernova remnants with the imaging detectors of the Einstein Observatory. X-ray surface brightness contours of 47 remnants are shown together with gray-scale pictures. Count rates for these remnants have been derived and are listed for the HRI, IPC, and MPC detectors.
Supporting the Next Einstein Initiative | IDRC - International ...
International Development Research Centre (IDRC) Digital Library (Canada)
Yet, at a time when strong math skills are needed to tackle urgent problems in the modern economy and the environment, there remains a critical scarcity of graduates with mathematical and ... The idea is that graduates of the Einstein Initiative will go on to assume leadership roles in academia, industry and government.
Albert Einstein the roads to pacifism
Anta, Claudio Giulio
2017-01-01
Albert Einstein (1879-1955) is universally known as the father of the theory of relativity; however, he was also one of the most eminent pacifists of the first half of the twentieth century. Through his active, pragmatic and nuanced breed of pacifism, he sought to confront the dilemmas and problems of his time.
Albert Einstein: Radical Pacifist and Democrat
Jayaraman, T.
We draw attention here to the radical political grounding of Einstein's pacifism. We also drescribe some less commonly known aspects of his commitment to civil liberties, particularly in the context of the anti-l hysteria and anti-racism current in the United States of the late 1940s and 1950s. We also examine briefly his views on socialism.
The Excellence of Einstein's Theory of Gravitation.
Dirac, P. A. M.
1979-01-01
This article is adapted from a presentation made in 1978 at the symposium on the Impact of Modern Scientific Ideas on Society organized by UNESCO in Ulm, West Germany. It discusses Einstein's theory of gravitation and how it started a new line of activity for physicists. (HM)
Albert Einstein, guide spirituel du CERN
Sandraz, Raphaël
2005-01-01
The year 2005, proclaimed "World year of Physics" by UNESCO, dedicates the 100th anniversary of the theory of relativity and the 50th anniversary of the death of his discoverer: Albert Einstein. The CERN in Geneva applies every day his theories (1 page)
Skyrmion physics in Bose-Einstein ferromagnets
Al Khawaja, U.; Stoof, H.T.C.
2001-01-01
We show that ferromagnetic Bose-Einstein condensate has not only line-like vortex excitations, but in general also allows for point-like topological excitations, i.e., skyrmions. We discuss the thermodynamic stability and the dynamic properties of these skyrmions for both spin-1/2 and ferromegnetic
Skyrmion physics in Bose-Einstein ferromagnets
Al Khawaja, U.; Stoof, H.T.C.
2001-01-01
We show that a ferromagnetic Bose-Einstein condensate has not only line-like vortex excitations, but in general, also allows for pointlike topological excitations, i.e., skyrmions. We discuss the thermodynamic stability and the dynamic properties of these skyrmions for both spin-1/2 and
On Einstein's opponents, and other crackpots
van Dongen, J.A.E.F.
2010-01-01
Einsteins Gegner: Die öffentliche Kontroverse um die Relativitätstheorie in den 1920er Jahren, Milena Wazeck. Campus Verlag, pp. 429, EUR 39.90. ISBN: 978-3593389141 “This world is a strange madhouse. Currently, every coachman and every waiter is debating whether relativity theory is correct. Belief
Einstein and the Special Theory of Relativity
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 3. Einstein and the Special Theory of Relativity. Supurna Sinha. General Article Volume 5 Issue 3 March 2000 pp 6-15. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/005/03/0006-0015 ...
Einstein and the Special Theory of Relativity
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 12. Einstein and the Special Theory of Relativity. Supurna Sinha. Volume 10 Issue 12 December 2005 pp 96-105. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/010/12/0096-0105 ...
Pollen Grains, Random Walks and Einstein
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 12. Pollen Grains, Random Walks and Einstein. Sriram Ramaswamy. Volume 10 Issue 12 December 2005 pp 106-124. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/010/12/0106-0124 ...
Pollen Grains, Random Walks and Einstein
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 3. Pollen Grains, Random Walks and Einstein. Sriram Ramaswamy. General Article Volume 5 Issue 3 March 2000 pp 16-34. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/005/03/0016-0034 ...
The EPR Paradox: Einstein Scrutinises Quantum Mechanics
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 4. The EPR Paradox: Einstein Scrutinises Quantum Mechanics. Arvind. General Article Volume 5 Issue 4 April 2000 pp 28-36. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/005/04/0028-0036 ...
Einstein's lessons for energy accounting in LCA
Frischknccht, Rolf; Heijungs, Reinout; Hofstetter, Patrick
1998-01-01
The role and meaning of accounting for energy, including feedstock energy, is reviewed in connection to Einstein's special theory of relativity. It is argued that there is only one unambiguous interpretation of the term energy-content: The one that corresponds to mc2. The implications for life cycle
New Information about Albert Einstein's Brain.
Falk, Dean
2009-01-01
In order to glean information about hominin (or other) brains that no longer exist, details of external neuroanatomy that are reproduced on endocranial casts (endocasts) from fossilized braincases may be described and interpreted. Despite being, of necessity, speculative, such studies can be very informative when conducted in light of the literature on comparative neuroanatomy, paleontology, and functional imaging studies. Albert Einstein's brain no longer exists in an intact state, but there are photographs of it in various views. Applying techniques developed from paleoanthropology, previously unrecognized details of external neuroanatomy are identified on these photographs. This information should be of interest to paleoneurologists, comparative neuroanatomists, historians of science, and cognitive neuroscientists. The new identifications of cortical features should also be archived for future scholars who will have access to additional information from improved functional imaging technology. Meanwhile, to the extent possible, Einstein's cerebral cortex is investigated in light of available data about variation in human sulcal patterns. Although much of his cortical surface was unremarkable, regions in and near Einstein's primary somatosensory and motor cortices were unusual. It is possible that these atypical aspects of Einstein's cerebral cortex were related to the difficulty with which he acquired language, his preference for thinking in sensory impressions including visual images rather than words, and his early training on the violin.
Albert Einstein and the Quantum Riddle
Lande, Alfred
1974-01-01
Derives a systematic structure contributing to the solution of the quantum riddle in Einstein's sense by deducing quantum mechanics from the postulates of symmetry, correspondence, and covariance. Indicates that the systematic presentation is in agreement with quantum mechanics established by Schroedinger, Born, and Heisenberg. (CC)
New stiff matter solutions to Einstein equations
Energy Technology Data Exchange (ETDEWEB)
Hajj-Boutros, J.
1989-01-01
New exact solutions are presented to the Einstein field equations which are spherically symmetric and static, with a perfect fluid distribution of matter satisfying the equation of state /rho/ = p. One of the obtained solutions may only be used locally, the other represents the stellar interior globally and is singularity-free.
Coexistence of photonic and atomic Bose-Einstein condensates in ideal atomic gases
Directory of Open Access Journals (Sweden)
N. Boichenko
2015-12-01
Full Text Available We have studied conditions of photon Bose-Einstein condensate formation that is in thermodynamic equilibrium with ideal gas of two-level Bose atoms below the degeneracy temperature. Equations describing thermodynamic equilibrium in the system were formulated; critical temperatures and densities of photonic and atomic gas subsystems were obtained analytically. Coexistence conditions of these photonic and atomic Bose-Einstein condensates were found. There was predicted the possibility of an abrupt type of photon condensation in the presence of Bose condensate of ground-state atoms: it was shown that the slightest decrease of the temperature could cause a significant gathering of photons in the condensate. This case could be treated as a simple model of the situation known as "stopped light" in cold atomic gas. We also showed how population inversion of atomic levels can be created by lowering the temperature. The latter situation looks promising for light accumulation in atomic vapor at very low temperatures.
General proof of entropy principle in Einstein-Maxwell theory
Fang, Xiongjun
2015-01-01
We consider a static self-gravitating charged perfect fluid system in the Einstein-Maxwell theory. Assume Maxwell's equation and the Einstein constraint equation are satisfied, and the temperature of the fluid obeys Tolman's law. Then we prove that the total entropy of the fluid achieves an extremum implies other components of Einstein's equation for any variations of metric and electrical potential with fixed boundary values. Conversely, if Einstein's equation and Maxwell's equations hold, the total entropy achieves an extremum. Our work suggests that the maximum entropy principle is consistent with Einstein's equation when electric field is taken into account.
Einstein's strugges with quantum theory a reappraisal
Home, Dipankar
2007-01-01
Einstein’s Struggles with Quantum Theory: A Reappraisal by Dipankar Home and Andrew Whitaker provides a detailed account of Albert Einstein’s thinking in regard to quantum physics. Until recently, most of Einstein’s views on quantum physics were dismissed and even ridiculed; some critics even suggested that Einstein was not able to grasp the complexities of the formalism of quantum theory and subtleties of the standard interpretation of this theory known as the Copenhagen interpretation put forward by Niels Bohr and his colleagues. But was that true? Modern scholarship argues otherwise, insist Drs. Home and Whitaker, who painstakingly explain the questions Einstein raised as well as offer a detailed discussion of Einstein’s position and major contributions to quantum theory, connecting them with contemporary studies on fundamental aspects of this theory. This unique book presents a mathematical as well as a non-mathematical route through the theories, controversies, and investigations, making the disc...
It's about time understanding Einstein's relativity
Mermin, N David
2005-01-01
In It's About Time, N. David Mermin asserts that relativity ought to be an important part of everyone's education--after all, it is largely about time, a subject with which all are familiar. The book reveals that some of our most intuitive notions about time are shockingly wrong, and that the real nature of time discovered by Einstein can be rigorously explained without advanced mathematics. This readable exposition of the nature of time as addressed in Einstein's theory of relativity is accessible to anyone who remembers a little high school algebra and elementary plane geometry. The book evolved as Mermin taught the subject to diverse groups of undergraduates at Cornell University, none of them science majors, over three and a half decades. Mermin's approach is imaginative, yet accurate and complete. Clear, lively, and informal, the book will appeal to intellectually curious readers of all kinds, including even professional physicists, who will be intrigued by its highly original approach.
How Einstein Discovered E0=mc2
Hecht, Eugene
2012-02-01
This paper traces Einstein's discovery of "the equivalence of mass [m] and energy [E0]." He came to that splendid insight in 1905 while employed by the Bern Patent Office, at which time he was not an especially ardent reader of physics journals. How then did the young savant, working outside of academia in semi-isolation, realize that these two seemingly disparate concepts were actually "identical"? Until now little attention has been given to exploring the physics that guided his thinking in this remarkable endeavor. That work culminated (1907) in the equation E0=mc2, where E0 is "rest energy" and m is "invariant mass." Despite claims to the contrary, Einstein did not write this equation, or its ambiguous variant, E =mc2, in 1905. Furthermore, we will propose a compelling reason for his otherwise inexplicable caution. This paper is meant to help clarify the contemporary literature in the service of an informed pedagogy.
Dynamical spacetimes and gravitational radiation in a Fully Constrained Formulation
Cordero-Carrión, Isabel; Ibáñez, José María
2010-01-01
This contribution summarizes the recent work carried out to analyze the behavior of the hyperbolic sector of the Fully Constrained Formulation (FCF) derived in Bonazzola et al. 2004. The numerical experiments presented here allows one to be confident in the performances of the upgraded version of CoCoNuT's code by replacing the Conformally Flat Condition (CFC) approximation of the Einstein equations by the FCF.
Scattering amplitudes in N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity
Chiodaroli, Marco; Johansson, Henrik; Roiban, Radu
2015-01-01
We expose a double-copy structure in the scattering amplitudes of the generic Jordan family of N=2 Maxwell-Einstein and Yang-Mills/Einstein supergravity theories in four and five dimensions. The Maxwell-Einstein supergravity amplitudes are obtained through the color/kinematics duality as a product of two gauge-theory factors; one originating from pure N=2 super-Yang-Mills theory and the other from the dimensional reduction of a bosonic higher-dimensional pure Yang-Mills theory. We identify a specific symplectic frame in four dimensions for which the on-shell fields and amplitudes from the double-copy construction can be identified with the ones obtained from the supergravity Lagrangian and Feynman-rule computations. The Yang-Mills/Einstein supergravity theories are obtained by gauging a compact subgroup of the isometry group of their Maxwell-Einstein counterparts. For the generic Jordan family this process is identified with the introduction of cubic scalar couplings on the bosonic gauge-theory side, which th...
Requena, Ángel
2005-01-01
Con motivo del centenario de la publicación de los Papeles de 1905 se conmemora mundialmente El Año de la Física, que está siendo el año Einstein. Los profesores de matemáticas tenemos ante nosotros un estimulante escenario para poner nuevamente de manifiesto el fecundo engarce de las teorías abstractas de la razón con las aparentemente ocultas leyes de la naturaleza.
Casimir effect in the rainbow Einstein's universe
Bezerra, V. B.; Mota, H. F.; Muniz, C. R.
2017-10-01
In the present paper we investigate the effects caused by the modification of the dispersion relation obtained by solving the Klein-Gordon equation in the closed Einstein's universe in the context of rainbow's gravity models. Thus, we analyse how the quantum vacuum fluctuations of the scalar field are modified when compared with the results obtained in the usual General Relativity scenario. The regularization, and consequently the renormalization, of the vacuum energy is performed adopting the Epstein-Hurwitz and Riemann's zeta functions.
Stellar coronae from Einstein - Observations and theory
Rosner, R.; Vaiana, G. S.
1980-01-01
Einstein Observatory observations of stellar X-ray emission are presented and their implications for the formation of stellar coronae and the problem of stellar angular momentum loss are discussed. Solar coronal X-ray observations and observations of stellar coronae made prior to Einstein are reviewed, and it is noted that they already suggest that the standard theory of acoustic coronal heating is inadequate. The principal results of the Einstein/CfA stellar survey are summarized, with attention given to variations of the level of X-ray flux detected along the main sequence, the decline of X-ray flux with increasing age of giants and supergiants, and indications of a large range of X-ray emission levels within a given type, which are clearly incompatible with models for acoustic flux generation. A new theory to explain stellar coronae and hence X-ray emission from them is then proposed in which stellar magnetic fields play the key role in determining the level of coronal emission, and the modulation of the surface magnetic flux level and the level of stressing of surface magnetic fields essentially determine the variation of mean coronal activity in the H-R diagram.
Kinematics of Einstein-Cartan universes
Pasmatsiou, Klaountia; Tsagas, Christos G.; Barrow, John D.
2017-05-01
We analyze the kinematics of cosmological spacetimes with nonzero torsion, in the framework of the classical Einstein-Cartan gravity. After a brief introduction to the basic features of spaces with nonvanishing torsion, we consider a family of observers moving along timelike worldlines and focus on their kinematic behavior. In so doing, we isolate the irreducible variables monitoring the observers' motion and derive their evolution formulas and associated constraint equations. Our aim is to identify the effects of spacetime torsion, and the changes they introduce into the kinematics of the standard, torsion-free, cosmological models. We employ a fully geometrical approach, imposing no restrictions on the material content, or any a priori couplings between torsion and spin. Also, we do not apply the familiar splitting of the equations, into a purely Riemannian component plus a torsion/spin part, at the start of our study, but only introduce it at the very end. With the general formulas at hand, we use the Einstein-Cartan field equations to incorporate explicitly the spin of the matter. The resulting formulas fully describe the kinematics of dynamical spacetimes within the framework of the Einstein-Cartan gravity, while in the special case of the so-called Weyssenhoff fluid, they recover results previously reported in the literature.
Romer, Robert H.
2005-04-01
Midway during my first year as a Princeton graduate student (1952-53), I was given a letter of introduction to Einstein. Over a year later I finally worked up my courage to use it and -- as a result -- enjoyed a one-on-one conversation with him in the study of his home on Mercer Street. I will describe how my chance to meet Einstein arose and what I can remember of our memorable (to me if not to him) conversation. Among other things, we discussed the bomb, the new state of Israel, fossil horse brains, and evolution. (``Has there really been enough time for all those changes?'') We talked about the Einstein-Rosen-Podolsky problem - though not by that name, and I believe that it was the ``Bohm version'' that he asked me about. (``Do you really believe that if someone here measured the spin of an atom, it could affect the simultaneous measurement of the spin of another atom way over there?'') My major recollection is of my wish that I had been better prepared. As Ehrenfest once wrote: ``Nothing is shabbier than the feeling: now God has granted me the opportunity to meet this man, and I sat before him open-mouthed; how much I might have asked him -- but nothing at all occurred to me.''
Energy Technology Data Exchange (ETDEWEB)
Nakamura, Y., E-mail: yusuke.n@asagi.waseda.jp [Department of Electronic and Physical Systems, Waseda University, Tokyo 169-8555 (Japan); Nagano Prefectural Kiso Seiho High School, Nagano 397-8571 (Japan); Kawaguchi, T., E-mail: pionelish30@toki.waseda.jp [Department of Electronic and Physical Systems, Waseda University, Tokyo 169-8555 (Japan); Torii, Y., E-mail: torii0139@asagi.waseda.jp [Department of Electronic and Physical Systems, Waseda University, Tokyo 169-8555 (Japan); Yamanaka, Y., E-mail: yamanaka@waseda.jp [Department of Electronic and Physical Systems, Waseda University, Tokyo 169-8555 (Japan)
2017-01-15
The formulation for zero mode of a Bose–Einstein condensate beyond the Bogoliubov approximation at zero temperature [Y. Nakamura et al., Phys. Rev. A 89 (2014) 013613] is extended to finite temperature. Both thermal and quantum fluctuations are considered in a manner consistent with a concept of spontaneous symmetry breakdown for a finite-size system. Therefore, we need a proper treatment of the zero mode operators, which invoke non-trivial enhancements in depletion condensate and thermodynamical quantities such as the specific heat. The enhancements are visible in the weak interaction case. Our approach reproduces the results of a homogeneous system in the Bogoliubov approximation in a large particle number limit.
Einstein's Materialism and Modern Tests of Quantum Mechanics
Vigier, J. P.
After a presentation of Einstein's and Bohr's antagonistic point of view on the interpretation of Quantum Mechanics an illustration of their conflicting positions in the particular case of Young's double slit experiment is presented. It is then shown that in their most recent form (i. e. time dependent neutron interferometry) these experiments suggest (if one accepts absolute energymomentum conservation in all individual microprocesses) that Einstein was right in the Bohr-Einstein controversy.Translated AbstractEinsteins Materialismus und heutige Tests der QuantenmechanikNach einer Darstellung von Einsteins und Bohrs antagonistischen Standpunkten in der Interpretation der Quantenmechanik werden ihre widersprüchlichen Positionen im speziellen Fall des Youngschen Doppelspaltexperiments dargestellt. Es wird dann gezeigt, daß diese Experimente in ihrer neuesten Form (d. h. zeitabhängige Neutroneninterferometrie) Einstein in der Bohr-Einsteinkontroverse recht gaben (wenn man absolute Energie-Impulserhaltung bei allen individuellen Mikroprozessen annimmt).
Einstein's Discovery of Gravitational Waves 1916-1918
Weinstein, Galina
2016-01-01
In his 1916 ground-breaking general relativity paper Einstein had imposed a restrictive coordinate condition, his field equations were valid for coordinate systems which are unimodular. Later, Einstein published a paper on gravitational waves. The solution presented in this paper did not satisfy the above restrictive condition. In his gravitational waves paper, Einstein concluded that gravitational fields propagate at the speed of light. The solution is the Minkowski flat metric plus a small disturbance propagating in a flat spacetime. Einstein calculated the small deviation from Minkowski metric in a manner analogous to that of retarded potentials in electrodynamics. However, in obtaining the above derivation, Einstein made a mathematical error. This error caused him to obtain three different types of waves compatible with his approximate field equations: longitudinal waves, transverse waves and a new type of wave. Einstein added an Addendum in which he suggested that in systems in unimodular coordinates onl...
Explicit formulae for Yang-Mills-Einstein amplitudes from the double copy
Chiodaroli, Marco; Günaydin, Murat; Johansson, Henrik; Roiban, Radu
2017-07-01
Using the double-copy construction of Yang-Mills-Einstein theories formulated in our earlier work, we obtain compact presentations for single-trace Yang-Mills-Einstein tree amplitudes with up to five external gravitons and an arbitrary number of gluons. These are written as linear combinations of color-ordered Yang-Mills trees, where the coefficients are given by color/kinematics-satisfying numerators in a Yang-Mills + ϕ 3 theory. The construction outlined in this paper holds in general dimension and extends straightforwardly to supergravity theories. For one, two, and three external gravitons, our expressions give identical or simpler presentations of amplitudes already constructed through string-theory considerations or the scattering equations formalism. Our results are based on color/kinematics duality and gauge invariance, and strongly hint at a recursive structure underlying the single-trace amplitudes with an arbitrary number of gravitons. We also present explicit expressions for all-loop single-graviton Einstein-Yang-Mills amplitudes in terms of Yang-Mills amplitudes and, through gauge invariance, derive new all-loop amplitude relations for Yang-Mills theory.
Un lugar entre la tierra y las estrellas. Luces y sombras en la Torre Einstein
Directory of Open Access Journals (Sweden)
Rafael Guridi García
2011-10-01
engineers from Carl-Zeiss, should go further and to express its architecture, the theory that tried to demonstrate in the inside. The mass-energy equivalence formulated by Einstein was translated architecturally into a game of mass and light, a balance of movement, in the words of the young architect.
Rather than expressing it, the tower "represented" movement, reproducing an instant frozen in time. Luise Mendelsohn referred to the works she often visited as the "construction of a ship", and in her dreams she saw it slip away navigating down the hill. Nautical references are not alien to this project: more than a ship, the Einstein tower resembles a surface submarine, with its tower and bow coming out and its body half-buried under a green layer that ripples and folds around it (submarines had been a weapon optimized during the recently finished war.
The drawings made at the war front by Erich Mendelsohn were populated by vigorous architectures, with expressive gestures, often with an industrial finish. They are autonomous giants, ignorant and independent from their environment, almost nonexistent. Their only tie to their context takes place in the ground; although the Modern Movement proposes a world of prefabricated, light and technological artifacts placed on the ground without making any changes to it, the imaginary architecture by the young Mendelsohn seems to be part of the ground that it comes out of. The Einstein Tower culminates that telluric relationship: its site must not be considered on the urban or even geographic scale; its location is tied to the planet in which it is inserted, and the star at which it gazes, day after day.
Einstein's photoemission emission from heavily-doped quantized structures
Ghatak, Kamakhya Prasad
2015-01-01
This monograph solely investigates the Einstein's Photoemission(EP) from Heavily Doped(HD) Quantized Structures on the basis of newly formulated electron dispersion laws. The materials considered are quantized structures of HD non-linear optical, III-V, II-VI, Ge, Te, Platinum Antimonide, stressed materials, GaP, Gallium Antimonide, II-V, Bismuth Telluride together with various types of HD superlattices and their Quantized counterparts respectively. The EP in HD opto-electronic materials and their nanostructures is studied in the presence of strong light waves and intense electric fields that control the studies of such quantum effect devices. The suggestions for the experimental determinations of different important physical quantities in HD 2D and 3D materials and the importance of measurement of band gap in HD optoelectronic materials under intense built-in electric field in nano devices and strong external photo excitation (for measuring physical properties in the presence of intense light waves w...
Nonlinear dynamics in the Einstein-Gauss-Bonnet gravity
Shinkai, Hisa-aki; Torii, Takashi
2017-08-01
We numerically investigated how nonlinear dynamics depends on the dimensionality and on the higher-order curvature corrections in the form of Gauss-Bonnet (GB) terms. We especially monitored the processes of appearances of a singularity (or black hole) in two models: (i) a perturbed wormhole throat in spherically symmetric space-time, and (ii) colliding scalar pulses in plane-symmetric space-time. We used a dual-null formulation for evolving the field equations, which enables us to locate the trapping horizons directly, and also enables us to follow close to the large-curvature region due to its causal integrating scheme. We observed that the fate of a perturbed wormhole is either a black hole or an expanding throat depending on the total energy of the structure, and its threshold depends on the coupling constant of the GB terms (αGB ). We also observed that a collision of large scalar pulses will produce a large-curvature region, of which the magnitude also depends on αGB. For both models, the normal corrections (αGB>0 ) work for avoiding the appearance of singularity, although it is inevitable. We also found that in the critical situation for forming a black hole, the existence of the trapped region in the Einstein-GB gravity does not directly indicate the formation of a black hole.
Winterberg, Friedwardt
2008-04-01
It was Albert Einstein who for the first time changed our view of the universe to be a non-euclidean curved space-time. And it was Wernher von Braun who blazed the trail to take us into this universe, leaving for the first time the gravitational field of our planet earth, with the landing a man on the moon the greatest event in human history. Both these great physicists did this on the shoulders of giants. Albert Einstein on the shoulders of his landsman, the mathematician Bernhard Riemann, and Wernher von Braun on the shoulders of Goddard and Oberth. Both Einstein and von Braun made a Faustian pact with the devil, von Braun by accepting research funds from Hitler, and Einstein by urging Roosvelt to build the atom bomb (against Hitler). Both of these great men later regretted the use of their work for the killing of innocent bystanders, even though in the end the invention of nuclear energy and space flight is for the benefit of man. Their example serves as a warning for all of us. It can be formulated as follows: ``Can I in good conscience accept research funds from the military to advance scientific knowledge, for weapons developed against an abstract enemy I never have met in person?'' Weapons if used do not differentiate between the scientist, who invented these weapons, and the non-scientist.
Einstein's cosmos how Albert Einstein's vision transformed our understanding of space and time
Kaku, Michio
2004-01-01
Few figures loom as large as Albert Einstein in our contemporary culture. It is truly remarkable that a man from such humble beginnings, an unemployed dreamer without a future or a job, who was written off by his professors as a hopeless loser, could to dare to scale the heights he reached. In this enlightening book Michio Kaku reasseses Einstein's work by centering on his three great theories - special relativity, general relativity and the Unified Field Theory. The first yielded the equation E =mc which is now such a fixture in our culture that it is practically a ubiquitous slogan. But the subsequent theories led to the Big Bang theory and have changed irrevocably the way we perceive time and space. Michio Kaku gives a new, refreshing look at the pioneering work of Einstein, giving a more accurate portrayal of his enduring legacy than previous biographies. As today's advanced physicists continue their intense search to fulfill Einstein's most cherished dream, a 'theory of everything', he is recognised as a...
Crystallization Formulation Lab
Federal Laboratory Consortium — The Crystallization Formulation Lab fills a critical need in the process development and optimization of current and new explosives and energetic formulations. The...
Vortex molecules in Bose-Einstein condensates
Nitta, Muneto; Eto, Minoru; Cipriani, Mattia
2013-01-01
Stable vortex dimers are known to exist in coherently coupled two component Bose-Einstein condensates (BECs). We construct stable vortex trimers in three component BECs and find that the shape can be controlled by changing the internal coherent (Rabi) couplings. Stable vortex N-omers are also constructed in coherently coupled N-component BECs. We classify all possible N-omers in terms of the mathematical graph theory. Next, we study effects of the Rabi coupling in vortex lattices in two-compo...
Wormholes in Einstein-Born-Infeld Gravity
Kim, Jin Young; Park, Mu-In
2018-01-01
We introduce a new approach to construct wormholes without introducing exotic matters in Einstein-Born-Infeld gravity with a cosmological constant. Contary to the conventional approach, the throat is located at the place where the solutions can be joined smoothly. The metric and its derivatives are continuous so that the exotic matters are not needed there. The exoticity of the energy-momentum tensor is not essential to sustain the wormhole. We also present a method to check the stability of wormholes in the new approach.
Wormholes in Einstein-Born-Infeld Gravity
Directory of Open Access Journals (Sweden)
Kim Jin Young
2018-01-01
Full Text Available We introduce a new approach to construct wormholes without introducing exotic matters in Einstein-Born-Infeld gravity with a cosmological constant. Contary to the conventional approach, the throat is located at the place where the solutions can be joined smoothly. The metric and its derivatives are continuous so that the exotic matters are not needed there. The exoticity of the energy-momentum tensor is not essential to sustain the wormhole. We also present a method to check the stability of wormholes in the new approach.
Einstein and the Changing Worldviews of Physics
Lehner, Christoph; Schemmel, Matthias
2012-01-01
This volume reviews conceptual conflicts at the foundations of physics now and in the past century. The focus is on the conditions and consequences of Einstein's pathbreaking achievements that sealed the decline of the classical notions of space, time, radiation, and matter, and resulted in the theory of relativity. Particular attention is paid to the implications of conceptual conflicts for scientific views of the world at large, thus providing the basis for a comparison of the demise of the mechanical worldview at the turn of the 20th century with the challenges presented by cosmology at the
Varying G. [in Einstein gravitation theory
Canuto, V.; Hsieh, S.-H.; Owen, J. R.
1979-01-01
The problem of the variation of the gravitational constant with cosmological time is critically analyzed. Since Einstein's equation does not allow G to vary on any time scale, no observational data can be analyzed within the context of the standard theory. The recently proposed scale covariant theory, which allows (but does not demand) G to vary, and which has been shown to have passed several standard cosmological tests, is employed to discuss some recent nonnull observational results which indicate a time variation of G.
Vortices and hysteresis in a rotating Bose-Einstein condensate with anharmonic confinement
DEFF Research Database (Denmark)
Jackson, A.D.; Kavoulakis, G.M.
2004-01-01
Vortices; Bose-Einstein condensation; phase diagrams; phase transformation Udgivelsesdato: 4 August......Vortices; Bose-Einstein condensation; phase diagrams; phase transformation Udgivelsesdato: 4 August...
Einstein and Jordan reconciled. A frame-invariant approach to scalar-tensor cosmology
Energy Technology Data Exchange (ETDEWEB)
Catena, R. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Pietroni, M. [INFN, Sezione di Padova (Italy); Scarabello, L. [INFN, Sezione di Padova (Italy)]|[Padua Univ. (Italy). Dipt. di Fisica
2006-04-15
Scalar-Tensor theories of gravity can be formulated in different frames, most notably, the Einstein and the Jordan one. While some debate still persists in the literature on the physical status of the different frames, a frame transformation amounts to a change of units, and then should not affect physical results. We analyze the issue in a cosmological context. In particular, we define all the relevant observables (redshift, distances, cross-sections,..) in terms of frame-independent quantities. Then, we give a frame-independent formulation of the Boltzmann equation, and outline its use in relevant examples such as particle freeze-out and the evolution of the CMB photon distribution function. Finally, we derive the gravitational equations for the frame-independent quantities at first order in perturbation theory. From a practical point of view, the present approach allows the simultaneous implementation of the good aspects of the two frames in a clear and straightforward way. (orig.)
Magnons interaction of spinor Bose–Einstein condensates in an ...
Indian Academy of Sciences (India)
Magnons; spin wave; dipolar spinor Bose–Einstein condensates. PACS Nos 03.75.Lm; 05.30.Jp; 75.30.Ds. Of late, the dipolar spinor Bose–Einstein condensates (BECs) trapped in optical potentials [1–3] have been studied extensively. It offers new opportunity to confirm the dynamics of periodic structure in solid-state ...
Extension of Einstein's Planetary Theory Based on Generalized ...
African Journals Online (AJOL)
In this article, the generalized Einstein's radial equation of motion in the equatorial plane of the Sun is transformed to obtain additional correction terms to all order of C2 to Einstein's planetary equation of motion and hence to the planetary parameters. Keywords: Radial Equation; Planetary Equation; Planetary parameters ...
Validity of the einstein relation in disordered organic semiconductors
Wetzelaer, G.A.H.; Koster, L.J.A.; Blom, P.W.M.
2011-01-01
It is controversial whether energetic disorder in semiconductors is already sufficient to violate the classical Einstein relation, even in the case of thermal equilibrium. We demonstrate that the Einstein relation is violated only under nonequilibrium conditions due to deeply trapped carriers, as in
Validity of the Einstein Relation in Disordered Organic Semiconductors
Wetzelaer, G. A. H.; Koster, L. J. A.; Blom, P. W. M.
2011-01-01
It is controversial whether energetic disorder in semiconductors is already sufficient to violate the classical Einstein relation, even in the case of thermal equilibrium. We demonstrate that the Einstein relation is violated only under nonequilibrium conditions due to deeply trapped carriers, as in
Black Hole Analogue in Bose–Einstein Condensation
Indian Academy of Sciences (India)
Abstract. We have proposed a black hole analogue in a Bose–Einstein condensation. By introducing the Painlevé co-ordinates and using K–G equations, we have obtained the critical temperature of the black hole analogue in a Bose–Einstein condensation.
Space and Time: From Antiquity to Einstein and Beyond
Indian Academy of Sciences (India)
on learning that Einstein was attempting to find a new theory of gravity to resolve the conflict between special relativity and. Newtonian gravity (1913). Keywords. Relativity, Big Bang, black holes, quantum gravity. Abhay Ashtekar. At the beginning of the 20th century, Einstein revolutionized the notions of space and time, first.
From the Classroom to Washington: Einsteins on Education Reform
Hughes, Kent H., Ed.; Byers, Elizabeth A., Ed.
2010-01-01
The Woodrow Wilson International Center for Scholars was delighted to host a group of current and former Albert Einstein Distinguished Educator Fellows as they celebrated the 20th anniversary of the fellowship program. Outstanding math and science teachers in America's K-12 schools, the Einstein Fellows spend a year (or sometimes two) working on…
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
Einstein as Armchair Detective: The Case of Stimulated Radiation
Indian Academy of Sciences (India)
truths in the process. As a case in point, we will look at. Einstein's 1917 paper titled 'On the quantum theory of radiation' where he predicted the existence of stimulated emission. While Einstein will always be remembered for his revolutionary relativity theories, his contributions to the early quantum theory are certainly of the ...
A Demonstration of Einstein's Equivalence of Gravity and Acceleration
Newburgh, Ronald
2008-01-01
In 1907, Einstein described a "Gedankenexperiment" in which he showed that free fall in a gravitational field is indistinguishable from a body at rest in an elevator accelerated upwards in zero gravity. This paper describes an apparatus, which is simple to make and simple to operate, that acts as an observable footnote to Einstein's example. It…
Data analysis challenges for the Einstein Telescope
Bosi, Leone; Porter, Edward K.
2011-02-01
The Einstein Telescope is a proposed third generation gravitational wave detector that will operate in the region of 1 Hz to a few kHz. As well as the inspiral of compact binaries composed of neutron stars or black holes, the lower frequency cut-off of the detector will open the window to a number of new sources. These will include the end stage of inspirals, plus merger and ringdown of intermediate mass black holes, where the masses of the component bodies are on the order of a few hundred solar masses. There is also the possibility of observing intermediate mass ratio inspirals, where a stellar mass compact object inspirals into a black hole which is a few hundred to a few thousand times more massive. In this article, we investigate some of the data analysis challenges for the Einstein Telescope such as the effects of increased source number, the need for more accurate waveform models and the some of the computational issues that a data analysis strategy might face.
Gravity Before Einstein and Schwinger Before Gravity
Trimble, Virginia L.
2012-05-01
Julian Schwinger was a child prodigy, and Albert Einstein distinctly not; Schwinger had something like 73 graduate students, and Einstein very few. But both thought gravity was important. They were not, of course, the first, nor is the disagreement on how one should think about gravity that is being highlighted here the first such dispute. The talk will explore, first, several of the earlier dichotomies: was gravity capable of action at a distance (Newton), or was a transmitting ether required (many others). Did it act on everything or only on solids (an odd idea of the Herschels that fed into their ideas of solar structure and sunspots)? Did gravitational information require time for its transmission? Is the exponent of r precisely 2, or 2 plus a smidgeon (a suggestion by Simon Newcomb among others)? And so forth. Second, I will try to say something about Scwinger's lesser known early work and how it might have prefigured his "source theory," beginning with "On the Interaction of Several Electrons (the unpublished, 1934 "zeroth paper," whose title somewhat reminds one of "On the Dynamics of an Asteroid," through his days at Berkeley with Oppenheimer, Gerjuoy, and others, to his application of ideas from nuclear physics to radar and of radar engineering techniques to problems in nuclear physics. And folks who think good jobs are difficult to come by now might want to contemplate the couple of years Schwinger spent teaching elementary physics at Purdue before moving on to the MIT Rad Lab for war work.
Liver transplantation at Hospital Israelita Albert Einstein
Directory of Open Access Journals (Sweden)
Sergio Mies
2005-09-01
Full Text Available Objective: To present patients and results of liver transplantationperformed by the Liver Unit team at the Hospital Israelita AlbertEinstein. Methods: The medical records of all patients transplantedby the team at the Liver Unit of the Hospital Israelita Albert Einstein,from January 2002 to June 2005, were analyzed. Results: Duringthis period, 328 transplants were performed and 64.3% were malerecipients; 64.9% were performed with cadaveric donor; 31.1%with living donors; and 4.3% were domino liver transplants. Thethree-year survival rate was 78% with cadaveric donors, 71.1%with living donor and 46.2% with domino liver transplant. The meanseverity index according to the Child-Pugh score was 8.7 (ChildB–9 and the median was 9 (Child B-9; the mean MELD score was17.6 and the median 18. Conclusion: The Liver Unit team has thelargest number of liver transplantation cases in Latin Americawith over 850 transplants performed and outcomes similar to theworld’s best centers.
The Infinite Universe of Einstein and Newton
Bruce, Barry
2003-04-01
Einstein's field equations for general relativity are solved for a static, phinfinite, isotropic and homogeneous Universe. One of the three solutions found, the ``infinite closed universe'', is shown to fit the data for the Hubble diagram better than the Big Bang model. Using general relativity, the force of gravity between two point particles is found. Utilizing this force and the infinite closed universe model, the force of gravity on a point particle in arbitrary motion due to the uniform mass density of the universe is calculated by an integration. This force is found to be equal to the force of inertia. In addition, the calculation explains Newton's First Law and the equivalence of inertial mass and gravitational mass. Lastly, Newton's Third Law is elicited by the extension of Einstein's general relativity to two-body interactions. These results show that the cosmological redshift and the physics that we know are the result of the uniform mass distribution of an infinite closed universe and gravity alone.
Einstein, cientista e filósofo?
Directory of Open Access Journals (Sweden)
Michel Paty
1993-12-01
Full Text Available A física, como prática filosófica, designa a escolha de ângulo de abordagem sob o qual é possível perceber características fundamentais da física. Assumimos que os papéis do físico e do filósofo não são tão demarcados e que a tarefa do físico é inseparavelmente enunciar a significação dos conceitos, estabelecendo sua identificação lógico-matemática, e ligá-los à experiência. Nesta perspectiva, a análise da atividade de Einstein, especialmente o exame da gênese da teoria da Relatividade restrita e das significações nos conceitos e enunciados da Relatividade restrita e geral nos leva à afirmação da tese expressa no epíteto Einstein filósofo. Para este percurso foi necessário então a crítica da corrente filosófica - Círculo de Viena - aparentemente mais próxima da atividade einsteniana, mas que só o tomou como referência na condição de físico. Em especial é analisada, e recusada, a tese de Reichenbach da separação entre o contexto de justificativa - ao qual se aplica a análise filosófica - e o contexto de descoberta - relegado exclusivamente ao campo da psicologia. Para esta crítica buscamos, nos processos de descoberta, não uma rígida estrutura lógica mas a noção mais ampla de racionalidade.Physics as philosophical practice points out the option of an approach which enables us to perceive fundamental features of physics. We maintain that the physicist and the philosopher play roles not so disjuncted and that the physicist's task is as much to enunciate the meaning of the concepts, establishing its logical and mathematic identification, as to link them to experience. With this point of view we analyze Einstein's activity with emphasis on the rise of Special Relativity Theory and the meaning of the concepts of Special and General Relativity. This analysis carries us to the thesis expressed in the title Einstein, philosopher. To this way we have needed to criticize that philosophical movement
The Geometry of Almost Einstein (2, 3, 5) Distributions
Sagerschnig, Katja; Willse, Travis
2017-01-01
We analyze the classic problem of existence of Einstein metrics in a given conformal structure for the class of conformal structures inducedf Nurowski's construction by (oriented) (2, 3, 5) distributions. We characterize in two ways such conformal structures that admit an almost Einstein scale: First, they are precisely the oriented conformal structures c that are induced by at least two distinct oriented (2, 3, 5) distributions; in this case there is a 1-parameter family of such distributions that induce c. Second, they are characterized by the existence of a holonomy reduction to SU(1, 2), SL(3, R), or a particular semidirect product SL(2, R) ltimes Q_+, according to the sign of the Einstein constant of the corresponding metric. Via the curved orbit decomposition formalism such a reduction partitions the underlying manifold into several submanifolds and endows each ith a geometric structure. This establishes novel links between (2, 3, 5) distributions and many other geometries - several classical geometries among them - including: Sasaki-Einstein geometry and its paracomplex and null-complex analogues in dimension 5; Kähler-Einstein geometry and its paracomplex and null-complex analogues, Fefferman Lorentzian conformal structures, and para-Fefferman neutral conformal structures in dimension 4; CR geometry and the point geometry of second-order ordinary differential equations in dimension 3; and projective geometry in dimension 2. We describe a generalized Fefferman construction that builds from a 4-dimensional Kähler-Einstein or para-Kähler-Einstein structure a family of (2, 3, 5) distributions that induce the same (Einstein) conformal structure. We exploit some of these links to construct new examples, establishing the existence of nonflat almost Einstein (2, 3, 5) conformal structures for which the Einstein constant is positive and negative.
Einstein's cosmology review of 1933: a new perspective on the Einstein-de Sitter model of the cosmos
O'Raifeartaigh, Cormac; O'Keeffe, Michael; Nahm, Werner; Mitton, Simon
2015-09-01
We present a first English translation and analysis of a little-known review of relativistic cosmology written by Albert Einstein in late 1932. The article, which was published in 1933 in a book of Einstein papers translated into French, contains a substantial review of static and dynamic relativistic models of the cosmos, culminating in a discussion of the Einstein-de Sitter model. The article offers a valuable contemporaneous insight into Einstein's cosmology in the early 1930s and confirms that his interest lay in the development of the simplest model of the cosmos that could account for observation. The article also confirms that Einstein did not believe that simplified relativistic models could give an accurate description of the early universe.
Directory of Open Access Journals (Sweden)
Chifu E. N.
2009-10-01
Full Text Available In this article, we formulate solutions to Einstein's geometrical field equations derived using our new approach. Our field equations exterior and interior to the mass distribution have only one unknown function determined by the mass or pressure distribution. Our obtained solutions yield the unknown function as generalizations of Newton's gravitational scalar potential. Thus, our solution puts Einstein's geometrical theory of gravity on same footing with Newton's dynamical theory; with the dependence of the field on one and only one unknown function comparable to Newton's gravitational scalar potential. Our results in this article are of much significance as the Sun and planets in the solar system are known to be more precisely oblate spheroidal in geometry. The oblate spheroidal geometries of these bodies have effects on their gravitational fields and the motions of test particles and photons in these fields.
EINSTEIN EQUATIONS FOR TETRAD FIELDS ECUACIONES DE EINSTEIN PARA CAMPOS TETRADOS
Directory of Open Access Journals (Sweden)
Héctor Torres-Silva
2008-11-01
Full Text Available Every metric tensor can be expressed by the inner product of tetrad fields. We prove that Einstein's equations for these fields have the same form as the stress-energy tensor of electromagnetism if the total external current . Using the Evans' unified field theory, we show that the true unification of gravity and electromagnetism is with source-free Maxwell equations.Todo tensor métrico puede ser expresado por el producto interno de campos tetrados. Se prueba que las ecuaciones de Einstein para esos campos tienen la misma forma que el tensor electromagnético de momento-energía si la corriente externa total es igual a cero. Usando la teoría de campo unificado de Evans se muestra que la verdadera unificación de la gravedad y el electromagnetismo es con las ecuaciones de Maxwell sin fuentes.
Einstein, race, and the myth of the cultural icon.
Jerome, Fred
2004-12-01
The most remarkable aspect of Einstein's 1946 address at Lincoln University is that it has vanished from Einstein's recorded history. Its disappearance into a historical black hole symbolizes what seems to happen in the creation of a cultural icon. It is but one of many political statements by Einstein to have met such a fate, though his civil rights activism is most glaringly missing. One explanation for this historical amnesia is that those who shape our official memories felt that Einstein's "controversial" friends like Paul Robeson and activities like co-chairing the anti-lynching crusade might tarnish Einstein as an icon. That icon, sanctified by Time magazine when it dubbed Einstein "Person of the Century" at the end of 1999, is a myth, albeit a marvelous one. Yet it is not so much the motive for the omission but the consequence of it that should concern us. Americans and the millions of Einstein fans around the world are left unaware that he was an outspoken, passionate, committed antiracist.
When champions meet: Rethinking the Bohr-Einstein debate
Landsman, N. P.
Einstein's philosophy of physics (as clarified by Fine, Howard, and Held) was predicated on his Trennungsprinzip, a combination of separability and locality, without which he believed objectification, and thereby "physical thought" and "physical laws', to be impossible. Bohr's philosophy (as elucidated by Hooker, Scheibe, Folse, Howard, Held, and others), on the other hand, was grounded in a seemingly different doctrine about the possibility of objective knowledge, namely the necessity of classical concepts. In fact, it follows from Raggio's Theorem in algebraic quantum theory that-within an appropriate class of physical theories-suitable mathematical translations of the doctrines of Bohr and Einstein are equivalent. Thus-upon our specific formalization-quantum mechanics accommodates Einstein's Trennungsprinzip if and only if it is interpreted à la Bohr through classical physics. Unfortunately, the protagonists themselves failed to discuss their differences in this constructive way, since their debate was dominated by Einstein's ingenious but ultimately flawed attempts to establish the "incompleteness" of quantum mechanics. This aspect of their debate may still be understood and appreciated, however, as reflecting a much deeper and insurmountable disagreement between Bohr and Einstein about the knowability of Nature. Using the theological controversy on the knowability of God as a analogy, we can say that Einstein was a Spinozist, whereas Bohr could be said to be on the side of Maimonides. Thus Einstein's off-the-cuff characterization of Bohr as a 'Talmudic philosopher' was spot-on.
The Dark Universe Through Einstein's Lens
Energy Technology Data Exchange (ETDEWEB)
Bard, Deborah [SLAC; Kavli Institute for Particle Astrophysics and Cosmology
2013-07-23
Bard's talk explains the phenomenon known as gravitational lensing and how astrophysicists use it to explore the 95 percent of the universe that remains unseen: dark matter and dark energy. One of the most surprising predictions made by Einstein's theory of relativity is that light doesn't travel through the universe in a straight line. The gravitational field of massive objects will deflect the path of light traveling past, giving some very dramatic effects. We see multiple images of quasars, galaxies smeared into arcs and circles and magnified images of the most distant objects in the universe. This explains how gravitational lensing was first observed and discusses how scientists use this phenomenon to study everything from exoplanets to dark matter to the structure of the universe and the mysterious dark energy.
Vortex Molecules in Bose-Einstein Condensates
Nitta, Muneto; Eto, Minoru; Cipriani, Mattia
2014-04-01
Stable vortex dimers are known to exist in coherently coupled two component Bose-Einstein condensates (BECs). We construct stable vortex trimers in three component BECs and find that the shape can be controlled by changing the internal coherent (Rabi) couplings. Stable vortex N-omers are also constructed in coherently coupled N-component BECs. We classify all possible N-omers in terms of the mathematical graph theory. Next, we study effects of the Rabi coupling in vortex lattices in two-component BECs. We find how the vortex lattices without the Rabi coupling known before are connected to the Abrikosov lattice of integer vortices with increasing the Rabi coupling. In this process, vortex dimers change their partners in various ways at large couplings. We then find that the Abrikosov lattices are robust in three-component BECs.
Bose-Einstein condensation in nonuniform media
Sa-Yakanit, Virulh; Yarunin, Vladimir; Nisamaneephong, Pornther
1998-02-01
The Bogoliubov model of a nonideal gas is developed for Bose-Einstein condensation (BEC) in media with broken translational symmetry. A decrease of the transition temperature Tλ is found as a function of the ratio {F 1}/{g 0}, where g0 is the interaction between the atoms of the condensate and F1 is the condensate-noncondensate interaction, generated by the nonhomogeneous property of the matter. The shift of Tλ in porous media experimentally found by Wong et al. [Phys. Rev. Lett. 65 (1990) 2410] is applied to estimate the ratio {F 1}/{g 0}, which is found to be equal to 0.1, and may be considered as a measure of the influence of the porosity on the interaction between the atoms.
Bose-Einstein condensation and superfluidity
Pitaevskii, Lev
2016-01-01
This volume introduces the basic concepts of Bose–Einstein condensation and superfluidity. It makes special reference to the physics of ultracold atomic gases; an area in which enormous experimental and theoretical progress has been achieved in the last twenty years. Various theoretical approaches to describing the physics of interacting bosons and of interacting Fermi gases, giving rise to bosonic pairs and hence to condensation, are discussed in detail, both in uniform and harmonically trapped configurations. Special focus is given to the comparison between theory and experiment, concerning various equilibrium, dynamic, thermodynamic, and superfluid properties of these novel systems. The volume also includes discussions of ultracold gases in dimensions, quantum mixtures, and long-range dipolar interactions.
Einstein and Time in Physics and Philosophy
Canales, Jimena
Current debates about time have left ``a hole at the heart of physics'' (Scientific American, Sept 2002). The main problem with contemporary explanations is usually traced to Einstein's theory of relativity, to the notion of a ``block universe,'' and to his famous claim that ``the distinction between the past, present and future is only a stubbornly persistent illusion.'' While some scientist have tried to incorporate elements of our experience of time into our explanations of the universe, others continue to claim that our sense of time is simply illusory. Can these debates be solved by science alone or are they inescapably philosophical, historical and cultural? My talk will explore the origins of this persistent quandary by focusing on the relation of physics to philosophy, history and the humanities. Can we solve the problem of time without engaging in ``Science Wars''?
What about Albert Einstein? Using Biographies to Promote Students' Scientific Thinking
Fingon, Joan C.; Fingon, Shallon D.
2009-01-01
Who hasn't heard of Einstein? Science educators everywhere are familiar with Einstein's genius and general theory of relativity. Students easily recognize Einstein's image by his white flyaway hair and bushy mustache. It is well known that Einstein was a brilliant physicist and an abstract thinker who often used his creativity and imagination in…
Emergent cosmos in Einstein-Cartan theory
Hadi, H.; Heydarzade, Y.; Hashemi, M.; Darabi, F.
2018-01-01
Based on Padmanabhan's proposal, the accelerated expansion of the universe can be driven by the difference between the surface and bulk degrees of freedom in a region of space, described by the relation dV/dt = N_sur-N_bulk where N_sur and N_bulk= -N_em +N_de are the degrees of freedom assigned to the surface area and the matter-energy content inside the bulk such that the indices "em" and "de" represent energy-momentum and dark energy, respectively. In the present work, the dynamical effect of the Weyssenhoff perfect fluid with intrinsic spin and its corresponding spin degrees of freedom in the framework of Einstein-Cartan (EC) theory are investigated. Based on the modification of Friedmann equations due to the spin-spin interactions, a correction term for Padmanabhan's original relation dV /d t=N_sur+N_em -N_de including the number of degrees of freedom related with these spin interactions is obtained through the modification in N_bulk term as N_bulk= -N_em+N_spin +N_de leading to dV /d t=N_sur+N_em-N_spin -N_de in which N_spin is the corresponding degrees of freedom related with the intrinsic spin of the matter content of the universe. Moreover, the validity of the unified first law and the generalized second law of thermodynamics for the Einstein-Cartan cosmos are investigated. Finally, by considering the covariant entropy conjecture and the bound resulting from the emergent scenario, a total entropy bound is obtained. Using this bound, it is shown that the for the universe as an expanding thermodynamical system, the total effective Komar energy never exceeds the square of the expansion rate with a factor of 3/4π.
EDITORIAL: Squeeze transformation and optics after Einstein
Kim, Young S.; Man'ko, Margarita A.; Planat, Michel
2005-12-01
With this special issue, Journal of Optics B: Quantum and Semiclassical Optics contributes to the celebration of the World Year of Physics held in recognition of five brilliant papers written by Albert Einstein in 1905. There is no need to explain to the readers of this journal the content and importance of these papers, which are cornerstones of modern physics. The 51 contributions in this special issue represent current trends in quantum optics —100 years after the concept of light quanta was introduced. At first glance, in his famous papers of 1905, Einstein treated quite independent subjects—special relativity, the nature and statistical properties of light, electrodynamics of moving bodies and Brownian motion. We now know that all these phenomena are deeply related, and these relations are clearly shown in many papers in this issue. Most of the papers are based on the talks and poster contributions from participants of the 9th International Conference on Squeezed States and Uncertainty Relations (ICSSUR'05), which took place in Besançon, France, 2-6 May, 2005. This was the continuation of a series of meetings, originating with the first workshops organized by Professor Y S Kim at the University of Maryland, College Park, USA, in 1991 and by Professor V I Man'ko at the Lebedev Physical Institute, Moscow in 1992. One of the main topics of ICSSUR'05 and this special issue is the theory and applications of squeezed states and their generalizations. At first glance, one could think that this subject has no relation to Einstein's papers. However, this is not true: the theory of squeezed states is deeply related to special relativity, as far as it is based on the representations of the Lorentz group (see the paper by Kim Y S and Noz M E, S458-S467), which also links the current concepts of entanglement and decoherence with Lorentz-covariance. Besides, studies of the different quantum states of light imply, after all, the study of photon (or photo
Einstein's physics atoms, quanta, and relativity : derived, explained, and appraised
Cheng, Ta-Pei
2013-01-01
Many regard Albert Einstein as the greatest physicist since Newton. What exactly did he do that is so important in physics? We provide an introduction to his physics at a level accessible to an undergraduate physics student. All equations are worked out in detail from the beginning. Einstein's doctoral thesis and his Brownian motion paper were decisive contributions to our understanding of matter as composed of molecules and atoms. Einstein was one of the founding fathers of quantum theory: his photon proposal through the investigation of blackbody radiation, his quantum theory of photoelectri
Competition between Bose-Einstein Condensation and Spin Dynamics.
Naylor, B; Brewczyk, M; Gajda, M; Gorceix, O; Maréchal, E; Vernac, L; Laburthe-Tolra, B
2016-10-28
We study the impact of spin-exchange collisions on the dynamics of Bose-Einstein condensation by rapidly cooling a chromium multicomponent Bose gas. Despite relatively strong spin-dependent interactions, the critical temperature for Bose-Einstein condensation is reached before the spin degrees of freedom fully thermalize. The increase in density due to Bose-Einstein condensation then triggers spin dynamics, hampering the formation of condensates in spin-excited states. Small metastable spinor condensates are, nevertheless, produced, and they manifest in strong spin fluctuations.
Einstein's pathway to the special theory of relativity
Weinstein, Galina
2015-01-01
This book pieces together the jigsaw puzzle of Einstein's journey to discovering the special theory of relativity. Between 1902 and 1905, Einstein sat in the Patent Office and may have made calculations on old pieces of paper that were once patent drafts. One can imagine Einstein trying to hide from his boss, writing notes on small sheets of paper, and, according to reports, seeing to it that the small sheets of paper on which he was writing would vanish into his desk-drawer as soon as he heard footsteps approaching his door. He probably discarded many pieces of papers and calculations and flu
An Einstein-Cartan Fine Structure Constant Definition
Directory of Open Access Journals (Sweden)
Stone R. A. Jr.
2010-01-01
Full Text Available The fine structure constant definition given in Stone R.A. Jr. Progress in Physics, 2010, v.1, 11-13 is compared to an Einstein-Cartan fine structure constant definition. It is shown that the Einstein-Cartan definition produces the correct pure theory value, just not the measure value. To produce the measured value, the pure theory Einstein-Cartan fine structure constant requires only the new variables and spin coupling of the fine structure constant definition in [1].
Einstein's Approach to Statistical Mechanics: The 1902-04 Papers
Peliti, Luca
2016-01-01
We summarize the papers published by Einstein in the Annalen der Physik in the years 1902-04 on the derivation of the properties of thermal equilibrium on the basis of the mechanical equations of motion and of the calculus of probabilities. We point out the line of thought that led Einstein to an especially economical foundation of the discipline, and to focus on fluctuations of the energy as a possible tool for establishing the validity of this foundation. We also sketch a comparison of Einstein's approach with that of Gibbs, suggesting that although they obtained similar results, they had different motivations and interpreted them in very different ways.
Janssen, Michel
2013-12-01
The core of this volume is formed by four chapters (2-5) with detailed reconstructions of the arguments and derivations in four of Einstein's most important papers, the three main papers of his annus mirabilis 1905 (on the light quantum, Brownian motion, and special relativity) and his first systematic exposition of general relativity of 1916. The derivations are given in sufficient detail and in sufficiently modernized notation (without any serious distortion of the originals) for an undergraduate physics major to read and understand them with far less effort than it would take him or her to understand (English translations of) Einstein's original papers. Each of these four papers is accompanied by a detailed introduction, which covers the conceptual development of the relevant field prior to Einstein's contribution to it and corrects some of the myths surrounding these papers that still have not been fully eradicated among physicists. (One quibble: though Kennedy correctly points out that the goal of the light quantum paper was not to explain the photoelectric effect, it is also not quite right to say that 'it was written to explain the Wien region of blackbody radiation' (p. xv). Einstein used this explanatory feat as the central argument for his light quantum hypothesis.) These four chapters then are the most valuable part of the volume. They could be used, independently of one another, but preferably in conjunction with Einstein's original texts, in courses on quantum mechanics, statistical mechanics, electrodynamics, and general relativity, respectively, to add a historical component to such courses. As a historian of science embedded in a physics department who is regularly called upon to give guest lectures in such courses on the history of their subjects, I can highly recommend the volume for this purpose. However, I would not adopt this volume as (one of) the central text(s) for a course on the history of modern physics. For one thing, chapter 1, which in
Dadhich, Naresh; Pons, Josep M
We study static black hole solutions in Einstein and Einstein-Gauss-Bonnet gravity with the topology of the product of two spheres, [Formula: see text], in higher dimensions. There is an unusual new feature of the Gauss-Bonnet black hole: the avoidance of a non-central naked singularity prescribes a mass range for the black hole in terms of [Formula: see text]. For an Einstein-Gauss-Bonnet black hole a limited window of negative values for [Formula: see text] is also permitted. This topology encompasses black strings, branes, and generalized Nariai metrics. We also give new solutions with the product of two spheres of constant curvature.
Einstein, 1905-2005 : Poincaré seminar
Darrigol, Olivier; Duplantier, B; Rivasseau, Vincent; Einstein 1905-2005 : séminaire Poincaré
2006-01-01
The Poincaré Seminar is held twice a year at the Institute Henri Poincaré in Paris. The goal of this seminar is to provide up-to-date information about general topics of great interest in physics. Both the theoretical and experimental results are covered, with some historical background. Particular care is devoted to the pedagogical nature of the presentation. This volume is devoted to Einstein's 1905 papers and their legacy. After a presentation of Einstein's epistemological approach to physics, and the genesis of special relativity, a centenary perspective is offered. The geometry of relativistic spacetime is explained in detail. Single photon experiments are presented, as a spectacular realization of Einstein's light quanta hypothesis. A previously unpublished lecture by Einstein, which presents an illuminating point of view on statistical physics in 1910, at the dawn of quantum mechanics, is reproduced. The volume ends with an essay on the historical, physical and mathematical aspects of Brownian motion...
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
Exactly solvable models for multiatomic molecular Bose-Einstein condensates
Energy Technology Data Exchange (ETDEWEB)
Santos, G, E-mail: gfilho@if.ufrgs.br, E-mail: gfilho@cbpf.br [Instituto de Fisica da UFRGS, Av. Bento Goncalves, 9500, Agronomia, Porto Alegre, RS (Brazil)
2011-08-26
I introduce two families of exactly solvable models for multiatomic hetero-nuclear and homo-nuclear molecular Bose-Einstein condensates through the algebraic Bethe ansatz method. The conserved quantities of the respective models are also shown. (paper)
Einstein's conversion from his static to an expanding universe
Nussbaumer, Harry
2014-02-01
In 1917 Einstein initiated modern cosmology by postulating, based on general relativity, a homogenous, static, spatially curved universe. To counteract gravitational contraction he introduced the cosmological constant. In 1922 Alexander Friedman showed that Albert Einstein's fundamental equations also allow dynamical worlds, and in 1927 Georges Lemaître, backed by observational evidence, concluded that our universe was expanding. Einstein impetuously rejected Friedman's as well as Lemaître's findings. However, in 1931 he retracted his former static model in favour of a dynamic solution. This investigation follows Einstein on his hesitating path from a static to the expanding universe. Contrary to an often advocated belief the primary motive for his switch was not observational evidence, but the realisation that his static model was unstable.
Albert Einstein and the Fizeau 1851 Water Tube Experiment
Weinstein, Galina
2012-01-01
In 1895 Hendrik Antoon Lorentz derived the Fresnel dragging coefficient in his theory of immobile ether and electrons. This derivation did not explicitly involve electromagnetic theory at all. According to the 1922 Kyoto lecture notes, before 1905 Einstein tried to discuss Fizeau's experiment "as originally discussed by Lorentz" (in 1895). At this time he was still under the impression that the ordinary Newtonian law of addition of velocities was unproblematic. In 1907 Max Laue showed that the Fresnel dragging coefficient would follow from a straightforward application of the relativistic addition theorem of velocities. This derivation is mathematically equivalent to Lorentz's derivation of 1895. From 1907 onwards Einstein adopted Laue's derivation. When Robert Shankland asked Einstein how he had learned of the Michelson-Morley experiment, Einstein told him that he had become aware of it through the writings of Lorentz, but only after 1905 had it come to his attention. "Otherwise", he said, "I would have ment...
Einstein's conversion from his static to an expanding universe
Nussbaumer, Harry
2013-01-01
In 1917 Einstein initiated modern cosmology by postulating, based on general relativity, a homogeneous, static, spatially curved universe. To counteract gravitational contraction he introduced the cosmological constant. In 1922 Alexander Friedman showed that Einstein's fundamental equation also allowed dynamical worlds, and in 1927 Geroges Lemaitre, backed by observational evidence, concluded that our universe was expanding. Einstein impetuously rejected Friedman's as well as Lemaitre's findings. However, in 1931 he retracted his former static model in favour of a dynamic solution. This investigation follows Einstein on his hesitating path from a static to the expanding universe. Contrary to an often repeated belief the primary motive for his switch was not observational evidence, but the realisation that his static model was unstable.
Mileva and Albert Einstein their love and scientific collaboration
Krstic, Dord
2004-01-01
This English translation of Dord Krstic's book, Mileva & Albert Einstein: Their Love and Scientific Collaboration represents the culmination of fifty years of research on the relationship between the two physicists.
The Einstein-Vlasov System/Kinetic Theory.
Andréasson, Håkan
2011-01-01
The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einstein's equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on non-relativistic and special relativistic physics, i.e., to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein-Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to a good comprehension of kinetic theory in general relativity.
Was Einstein wrong? Space station research may find out
2002-01-01
Experiments using ultra-precise clocks on the International Space Station will attempt to check if Einstein's Special Theory of Relativity is correct. Future experiments may also yield evidence of string theory (1 page).
Relativity and Gravitation : 100 Years After Einstein in Prague
Ledvinka, Tomáš; General Relativity, Cosmology and Astrophysics : Perspectives 100 Years After Einstein's Stay in Prague
2014-01-01
In early April 1911 Albert Einstein arrived in Prague to become full professor of theoretical physics at the German part of Charles University. It was there, for the first time, that he concentrated primarily on the problem of gravitation. Before he left Prague in July 1912 he had submitted the paper “Relativität und Gravitation: Erwiderung auf eine Bemerkung von M. Abraham” in which he remarkably anticipated what a future theory of gravity should look like. At the occasion of the Einstein-in-Prague centenary an international meeting was organized under a title inspired by Einstein's last paper from the Prague period: "Relativity and Gravitation, 100 Years after Einstein in Prague". The main topics of the conference included: classical relativity, numerical relativity, relativistic astrophysics and cosmology, quantum gravity, experimental aspects of gravitation, and conceptual and historical issues. The conference attracted over 200 scientists from 31 countries, among them a number of leading experts in ...
Electrostatics and confinement in Einstein's unified field theory
Antoci, S.; Liebscher, D. -E.; Mihich, L.
2007-01-01
A way for appending sources at the right-hand sides of the field equations of Einstein's unified field theory is recalled. Two exact solutions endowed with point sources in equilibrium are shown, and their physical meaning is discussed.
A comparative analysis of perspectives of Mileva Maric Einstein
Barnett, Carol C.
This dissertation examines the controversy surrounding Mileva Maric Einstein and the allegations subsequent to the publication of love letters during the time that Mileva Maric and Albert Einstein were students and during the early years of their marriage. It also examines the role of women in science from a historical perspective. Chapter One surveys the history of women in science from antiquity to the late nineteenth century and the patterns of gender related and restricting practices such as education, publication, the problem of mentoring and the issue of the lack of historical recognition. Chapter Two provides a comparative analyses between the lives of Mileva Maric Einstein and Marie Sklodowska Curie. Both had very similar social and educational backgrounds yet Marie Curie was able to work and publish jointly with her husband and received (although belatedly) international recognition for her work. On the other hand, Mileva Maric Einstein was never able to complete her degree and lived a life of obscurity and unfulfilled professional dreams. Both highly educated and intelligent women, but with drastically different outcomes in their professional and personal lives. Chapter Three examines the one book devoted to the life of Mileva Maric Einstein, Im Schatten Albert Einsteins: Das Tragische Leben der Mileva Einstein-Maric (In The Shadow of Albert Einstein: The Tragic Life of Mileva Maric), by Desanka Trbuhovic-Gjuric, Paul Haupt Publishers, 1985. It addresses the subjective as well as constructive and destructive criticisms of the various critical camps and provides examples of the statements made by the author which prompted a controversy within the academic and scientific communities. Appropriate responses are provided from various members of the scientific community to reflect the diversity of opinion and the intensity of the debate. Chapter Four addresses the problem of historicity and various interpretations of evidence which might suggest that the role
A complete public archive for the Einstein IPC
Helfand, David J.
1995-01-01
This report documents progress made in the period 24 Sept. 1993 - 23 Sept. 1995 on the project described in our proposal 'A Complete Public Archive for the Einstein IPC' which was approved under the Astrophysics Data Program in 1992. We have completed most of the principal objectives of the original proposal; a NFE was recently approved so that costs for publications in press can be covered and we can complete the public record for the Einstein IPC database.
Differential invariants and exact solutions of the Einstein equations
Lychagin, Valentin; Yumaguzhin, Valeriy
2017-06-01
In this paper (cf. Lychagin and Yumaguzhin, in Anal Math Phys, 2016) a class of totally geodesics solutions for the vacuum Einstein equations is introduced. It consists of Einstein metrics of signature (1,3) such that 2-dimensional distributions, defined by the Weyl tensor, are completely integrable and totally geodesic. The complete and explicit description of metrics from these class is given. It is shown that these metrics depend on two functions in one variable and one harmonic function.
Kähler-Einstein metrics: Old and New
Directory of Open Access Journals (Sweden)
Angella Daniele
2017-12-01
Full Text Available We present classical and recent results on Kähler-Einstein metrics on compact complex manifolds, focusing on existence, obstructions and relations to algebraic geometric notions of stability (K-stability. These are the notes for the SMI course "Kähler-Einstein metrics" given by C.S. in Cortona (Italy, May 2017. The material is not intended to be original.
Time-Periodic Einstein-Klein-Gordon Bifurcations of Kerr
Chodosh, Otis; Shlapentokh-Rothman, Yakov
2017-12-01
We construct one-parameter families of solutions to the Einstein-Klein-Gordon equations bifurcating off the Kerr solution such that the underlying family of spacetimes are each an asymptotically flat, stationary, axisymmetric, black hole spacetime, and such that the corresponding scalar fields are non-zero and time-periodic. An immediate corollary is that for these Klein-Gordon masses, the Kerr family is not asymptotically stable as a solution to the Einstein-Klein-Gordon equations.
A conformal and covariant formulation of the Z4 system with constraint-violation damping
Alic, Daniela; Bona, Carles; Rezzolla, Luciano; Palenzuela, Carlos
2011-01-01
We present a new formulation of the Einstein equations based on a conformal and traceless decomposition of the covariant form of the Z4 system. This formulation combines the advantages of a conformal decomposition, such as the one used in the BSSNOK formulation (i.e. well-tested hyperbolic gauges, no need for excision, robustness to imperfect boundary conditions) with the advantages of a constraint-damped formulation, such as the generalized harmonic one (i.e. exponential decay of constraint violations when these are produced). We validate the new set of equations through standard tests and by evolving binary systems of black holes. Overall, the new conformal formulation leads to a better behaviour of the constraint equations and a rapid suppression of the violations when they occur. The changes necessary to implement the new conformal formulation in standard BSSNOK codes are very small as are the additional computational costs.
Ferroelectricity by Bose-Einstein condensation in a quantum magnet.
Kimura, S; Kakihata, K; Sawada, Y; Watanabe, K; Matsumoto, M; Hagiwara, M; Tanaka, H
2016-09-26
The Bose-Einstein condensation is a fascinating phenomenon, which results from quantum statistics for identical particles with an integer spin. Surprising properties, such as superfluidity, vortex quantization or Josephson effect, appear owing to the macroscopic quantum coherence, which spontaneously develops in Bose-Einstein condensates. Realization of Bose-Einstein condensation is not restricted in fluids like liquid helium, a superconducting phase of paired electrons in a metal and laser-cooled dilute alkali atoms. Bosonic quasi-particles like exciton-polariton and magnon in solids-state systems can also undergo Bose-Einstein condensation in certain conditions. Here, we report that the quantum coherence in Bose-Einstein condensate of the magnon quasi particles yields spontaneous electric polarization in the quantum magnet TlCuCl 3 , leading to remarkable magnetoelectric effect. Very soft ferroelectricity is realized as a consequence of the O(2) symmetry breaking by magnon Bose-Einstein condensation. The finding of this ferroelectricity will open a new window to explore multi-functionality of quantum magnets.
Einstein's aborted attempt at a dynamic steady-state universe
Nussbaumer, Harry
2014-01-01
In June 1930 Einstein visited Cambridge where he stayed with Eddington who had just shown that Einstein's supposedly static universe of 1917 was not stable. This forced Einstein to rethink his cosmology. He spent January and February 1931 at Pasadena. There, he discussed cosmology intensely with Tolman, conscious that he had to replace his original model of 1917. However, at the end of February he still had not made up his mind about an alternative. The Albert Einstein Archives of Jerusalem (AEA) hold an undated draft, handwritten by Einstein, which I date to the beginning of January 1931. In this draft Einstein hopes to have found a solution to the cosmological problem: a stationary, dynamic universe in expansion. His model was stationary because particles leaving a given volume were replaced by particles created out of the vacuum, anticipating an idea of Bondi, Gold and Hoyle published in 1948. He saw the cosmological term as energy reservoir. However, he realised that his calculations contained a numerical...
Einstein's 1917 static model of the universe: a centennial review
O'Raifeartaigh, Cormac; O'Keeffe, Michael; Nahm, Werner; Mitton, Simon
2017-08-01
We present a historical review of Einstein's 1917 paper ` Cosmological Considerations in the General Theory of Relativity' to mark the centenary of a key work that set the foundations of modern cosmology. We find that the paper followed as a natural next step after Einstein's development of the general theory of relativity and that the work offers many insights into his thoughts on relativity, astronomy and cosmology. Our review includes a description of the observational and theoretical background to the paper; a paragraph-by-paragraph guided tour of the work; a discussion of Einstein's views of issues such as the relativity of inertia, the curvature of space and the cosmological constant. Particular attention is paid to little-known aspects of the paper such as Einstein's failure to test his model against observation, his failure to consider the stability of the model and a mathematical oversight concerning his interpretation of the role of the cosmological constant. We recall the response of theorists and astronomers to Einstein's cosmology in the context of the alternate models of the universe proposed by Willem de Sitter, Alexander Friedman and Georges Lemaître. Finally, we consider the relevance of the Einstein World in today's `emergent' cosmologies.
Ehrenfest en Einstein. Menselijke katalysator van het heldere denken
Directory of Open Access Journals (Sweden)
Marijn J. Hollestelle
2016-10-01
Full Text Available Ehrenfest and EinsteinEhrenfest and Einstein met just before Ehrenfest became professor at Leiden University. They had much in common and became best friends. Ehrenfest shed light on some problematic aspects of Einstein’s work and during the years acted as an important sparring partner for Einstein. Ehrenfest also explained difficult aspects of Einstein’s work to the physics community. He set others on the track of working on general relativity and made Leiden an international centre for these developments during the years 1912–1920. Ehrenfest made sure Einstein was appointed part-time professor at Leiden, from which Leiden physics profited. He also aided Bohr and Einstein during their notorious debates. Ehrenfest struggled with depression his whole life. The rapid developments and mathematicising of quantum physics, Hitler’s appointment as Reichs Chancellor, money and marriage problems worsened his depressions. In 1933 Ehrenfest committed suicide, and Einstein moved to the United States and away from the study on quantum physics.
Gabriele Veneziano : "La physique moderne doit dépasser Einstein et explorer l'avant-Big Bang"
Deschamps, Pascale-Marie
2004-01-01
Interview with Gabriele Veneziana: in search of the infinitesimally small and infinitesimally large, the Standard Model of elementary particles and Einstein's general relativity are not enough to explain the universe. The "visible" matter predicted by the Standard Model represents only 5% of the energy of the Universe, the dark "invisible" matter constitutes 25 to 30%. Therefore 65 to 70 % of something else is missing. String theory calls into question all that one knows of the primordial universe formulated by the Standard Model (4 pages)
Scientists present their design for Einstein Telescope
ASPERA Press Release
2011-01-01
Plans shape up for a revolutionary new observatory that will explore black holes and the Big Bang. This detector will ‘see’ the Universe in gravitational waves. A new era in astronomy will come a step closer when scientists from across Europe present their design study today for an advanced observatory capable of making precision measurements of gravitational waves – minute ripples in the fabric of spacetime – predicted to emanate from cosmic catastrophes such as merging black holes and collapsing stars and supernovae. It also offers the potential to probe the earliest moments of the Universe just after the Big Bang, which are currently inaccessible. The Einstein Observatory (ET) is a so-called third-generation gravitational-wave (GW) detector, which will be 100 times more sensitive than current instruments. Like the first two generations of GW detectors, it is based on the measurement of tiny changes (far less than the size of an atomic nucleus) in the le...
Einstein's greatest mistake abandonment of the aether
Deutsch, Sid
2006-01-01
If a child wants proof, we can think of 10 different ways to show that we are surrounded by air, but we are, of course, normally unaware that we live at the bottom of an “ocean” of air. It is claimed, in this book, that we are unaware, similarly, that we are surrounded by an atmosphere of aether. There is one major difference, however: We have not been able to detect the aether. Nevertheless, the aether provides a solution to the following mystery: How can light, or any electromagnetic wave, travel for billions of years across the vastness of the Universe, without losing any energy? The answer is that the Universe is filled with a light-transmitting medium, The Aether. The proof that there is an aether is the subject of the present book. An intriguing…exploration of a fringe scientific theory. Luminiferous aether—or "light-bearing aether," a theory first postulated by Isaac Newton in the 18th century, later refined by James Clerk Maxwell in the 19th century and ultimately replaced by Albert Einstein'...
Kinematics of Einstein-Cartan universes
Pasmatsiou, Klaountia; Barrow, John D
2016-01-01
We analyse the kinematics of cosmological spacetimes with nonzero torsion, in the framework of the classical Einstein-Cartan gravity. After a brief introduction to the basic features of spaces with non-vanishing torsion, we consider a family of observers moving along timelike worldlines and focus on their kinematic behaviour. In so doing, we isolate the irreducible variables monitoring the observers' motion and derive their evolution formulae and associated constraint equations. Our aim is to identify the effects of spacetime torsion, and the changes they introduce into the kinematics of the standard, torsion-free, cosmological models. We employ a fully geometrical approach, imposing no restrictions on the material content, or any a priori couplings between torsion and spin. Also, we do not apply the familiar splitting of the equations, into a purely Riemannian component plus a torsion/spin part, at the start of our study, but only introduce it at the very end. With the general formulae at hand, we use the Ei...
The Einstein-Boltzmann equations revisited
Nadkarni-Ghosh, Sharvari; Refregier, Alexandre
2017-10-01
The linear Einstein-Boltzmann (E-B) equations describe the evolution of perturbations in the universe and its numerical solutions play a central role in cosmology. We revisit this system of differential equations and present a detailed investigation of its mathematical properties. For this purpose, we focus on a simplified set of equations aimed at describing the broad features of the matter power spectrum. We first perform an eigenvalue analysis and study the onset of oscillations in the system signalled by the transition from real to complex eigenvalues. We then provide a stability criterion of different numerical schemes for this linear system and estimate the associated step size. We elucidate the stiffness property of the E-B system and show how it can be characterized in terms of the eigenvalues. While the parameters of the system are time dependent making it non-autonomous, we define an adiabatic regime where the parameters vary slowly enough for the system to be quasi-autonomous. We summarize the different regimes of the system for these different criteria as function of wavenumber k and scalefactor a. We also provide a compendium of analytic solutions for all perturbation variables in six limits on the k-a plane and express them explicitly in terms of initial conditions. These results are aimed to help the further development and testing of numerical cosmological Boltzmann solvers.
Gheorghiu, Tamara; Vacaru, Olivia; Vacaru, Sergiu I
2016-01-01
We study geometric relativistic flow and Ricci soliton equations which (for respective nonholonomic constraints and self-similarity conditions) are equivalent to the gravitational field equations of $R^2$ gravity and/or to the Einstein equations with scalar field in general relativity, GR. Perelman's functionals are generalized for modified gravity theories, MGTs, which allows to formulate an analogous statistical thermodynamics for geometric flows and Ricci solitons. There are constructed and analyzed generic off-diagonal black ellipsoid, black hole and solitonic exact solutions in MGTs and GR encoding geometric flow evolution scenarios and nonlinear parametric interactions. Such new classes of solutions in MGTs can be with polarized and/or running constants, nonholonomically deformed horizons and/or imbedded self-consistently into solitonic backgrounds. They exist also in GR as generic off-diagonal vacuum configurations with effective cosmological constant and/or mimicking effective scalar field interaction...
The many faces of Maxwell, Dirac and Einstein equations a Clifford bundle approach
Rodrigues, Jr, Waldyr A
2016-01-01
This book is an exposition of the algebra and calculus of differential forms, of the Clifford and Spin-Clifford bundle formalisms, and of vistas to a formulation of important concepts of differential geometry indispensable for an in-depth understanding of space-time physics. The formalism discloses the hidden geometrical nature of spinor fields. Maxwell, Dirac and Einstein fields are shown to have representatives by objects of the same mathematical nature, namely sections of an appropriate Clifford bundle. This approach reveals unity in diversity and suggests relationships that are hidden in the standard formalisms and opens new paths for research. This thoroughly revised second edition also adds three new chapters: on the Clifford bundle approach to the Riemannian or semi-Riemannian differential geometry of branes; on Komar currents in the context of the General Relativity theory; and an analysis of the similarities and main differences between Dirac, Majorana and ELKO spinor fields. The exercises with solut...
Explosive Formulation Pilot Plant
Federal Laboratory Consortium — The Pilot Plant for Explosive Formulation supports the development of new explosives that are comprised of several components. This system is particularly beneficial...
Miller, Steven David
1999-10-01
A consistent extension of the Oppenheimer-Snyder gravitational collapse formalism is presented which incorporates stochastic, conformal, vacuum fluctuations of the metric tensor. This results in a tractable approach to studying the possible effects of vacuum fluctuations on collapse and singularity formation. The motivation here, is that it is known that coupling stochastic noise to a classical field theory can lead to workable methodologies that accommodate or reproduce many aspects of quantum theory, turbulence or structure formation. The effect of statistically averaging over the metric fluctuations gives the appearance of a deterministic Riemannian structure, with an induced non-vanishing cosmological constant arising from the nonlinearity. The Oppenheimer-Snyder collapse of a perfect fluid or dust star in the fluctuating or `turbulent' spacetime, is reformulated in terms of nonlinear Einstein-Langevin field equations, with an additional noise source in the energy-momentum tensor. The smooth deterministic worldlines of collapsing matter within the classical Oppenheimer-Snyder model, now become nonlinear Brownian motions due to the backreaction induced by vacuum fluctuations. As the star collapses, the matter worldlines become increasingly randomized since the backreaction coupling to the vacuum fluctuations is nonlinear; the input assumptions of the Hawking-Penrose singularity theorems should then be violated. Solving the nonlinear Einstein-Langevin field equation for collapse - via the Ito interpretation - gives a singularity-free solution, which is equivalent to the original Oppenheimer solution but with higher-order stochastic corrections; the original singular solution is recovered in the limit of zero vacuum fluctuations. The `geometro-hydrodynamics' of noisy gravitational collapse, were also translated into an equivalent mathematical formulation in terms of nonlinear Einstein-Fokker-Planck (EFP) continuity equations with respect to comoving coordinates
El universo de Einstein: 1905 - annus mirabilis - 2005
Gangui, Alejandro
2007-01-01
Year 2005 was the World Year of Physics, and it was commemorated worldwide as the 100th anniversary of Albert Einstein's legendary works in which the foundations of at least three areas of modern physics were laid: statistical mechanics, quantum mechanics and special relativity. These works turned year 1905 in what deservedly was called the "miraculous year" (annus mirabilis) of Einstein. However, the influence of this great mind was not limited to science. As it is well known, his fingerprint remains engraved in many aspects of our daily life. Because of that, in this work we have tried to cover almost all the subjects in which Einstein was involved during the last century and, of course, try and reveal the future projection his actions will have in this new century that has just begun. Among the subjects covered in the volume one can find the possible connection between Einstein and the artistic vanguard movement, his religiosity, his days in Argentina, the Nobel Prize, the Einstein-Freud correspondence, hi...
More accurate theory for Bose-Einstein condensation fraction
Energy Technology Data Exchange (ETDEWEB)
Biswas, Shyamal [Department of Theoretical Physics, Indian Association for the Cultivation of Science Jadavpur, Kolkata-700032 (India)], E-mail: tpsb@iacs.res.in
2008-03-03
Bose-Einstein statistics is derived in the thermodynamic limit when the ratio of system size to thermal de Broglie wavelength goes to infinity. However, according to the experimental setup of Bose-Einstein condensation of harmonically trapped Bose gas of alkali atoms, the ratio near the condensation temperature (T{sub o}) is 30-50. And, at ultralow temperatures well below T{sub o}, this ratio becomes comparable to 1. We argue that finite size as well as the ultralow temperature induces corrections to Bose-Einstein statistics. From the corrected statistics we plot condensation fraction versus temperature graph. This theoretical plot satisfies well with the experimental plot [A. Griesmaier et al., Phys. Rev. Lett. 94 (2005) 160401].
How to obtain the Schwarzschild metric before Einstein's field equations
Kassner, Klaus
2016-01-01
As is well-known, there is no way to derive the Schwarzschild metric on the basis of pre-general-relativistic physics alone, which means using only special relativity, the Einstein equivalence principle and the Newtonian limit. It is however possible to encode the additional physics needed in two reasonably plausible postulates allowing to deduce the exact Schwarzschild metric without invoking Einstein's field equations. Since these requirements are designed to apply to the spherically symmmetric case, their union is much less powerful than the postulates from which Einstein obtained his field equations. It is shown that the field equations imply the postulates given here but that the converse is not quite true. The approach provides a fairly fast calculation method for the Schwarzschild metric in arbitrary coordinates exhibiting stationarity.
Albert Einstein and Friedrich Dessauer: Political Views and Political Practice
Goenner, Hubert
In this case study I compare the political views of the physicists Albert Einstein and Friedrich Dessauer between the first and second world wars, and I investigate their translation into concrete political practice. Both departed from their roles as experts in physics in favor of political engagement. The essence of Einstein's political practice seems to have been a form of political participation in exerting moral influence on people and organizations through public declarations and appeals in isolation from political mass movements. Dessauer exerted political influence both through public office (as a member of Parliament for the Catholic Center Party) and by acquiring a newspaper. The different political practice of both Einstein and Dessauer were unsuccessful in thwarting the Nazi takeover.
Mass discrepancy-acceleration relation in Einstein rings
Tian, Yong; Ko, Chung-Ming
2017-11-01
We study the mass discrepancy-acceleration relation (MDAR) of 57 elliptical galaxies by their Einstein rings from the Sloan Lens ACS Survey (SLACS). The mass discrepancy between the lensing mass and the baryonic mass derived from population synthesis is larger when the acceleration of the elliptical galaxy lenses is smaller. The MDAR is also related to surface mass density discrepancy. At the Einstein ring, these lenses belong to high-surface-mass density galaxies. Similarly, we find that the discrepancy between the lensing and stellar surface mass density is small. It is consistent with the recent discovery of dynamical surface mass density discrepancy in disc galaxies where the discrepancy is smaller when surface density is larger. We also find relativistic modified Newtonian dynamics (MOND) can naturally explain the MDAR and surface mass density discrepancy in 57 Einstein rings. Moreover, the lensing mass, the dynamical mass and the stellar mass of these galaxies are consistent with each other in relativistic MOND.
Bose-Einstein correlations in W-pair decays
Barate, R.; Decamp, D.; Ghez, P.; Goy, C.; Jezequel, S.; Lees, J.-P.; Martin, F.; Merle, E.; Minard, M.-N.; Pietrzyk, B.; Alemany, R.; Bravo, S.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Graugés, E.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L. M.; Morawitz, P.; Pacheco, A.; Riu, I.; Ruiz, H.; Colaleo, A.; Creanza, D.; de Palma, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Boix, G.; Buchmüller, O.; Cattaneo, M.; Cerutti, F.; Ciulli, V.; Davies, G.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Gianotti, F.; Greening, T. C.; Halley, A. W.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Kado, M.; Leroy, O.; Maley, P.; Mato, P.; Minten, A.; Moutoussi, A.; Ranjard, F.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Spagnolo, P.; Tejessy, W.; Teubert, F.; Tournefier, E.; Valassi, A.; Wright, A. E.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Dessagne, S.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Pascolo, J. M.; Perret, P.; Podlyski, F.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Vayaki, A.; Blondel, A.; Brient, J.-C.; Machefert, F.; Rougé, A.; Swynghedauw, M.; Tanaka, R.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Chalmers, M.; Kennedy, J.; Lynch, J. G.; Negus, P.; O'Shea, V.; Raeven, B.; Smith, D.; Teixeira-Dias, P.; Thompson, A. S.; Ward, J. J.; Cavanaugh, R.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Leibenguth, G.; Putzer, A.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Marinelli, N.; Martin, E. B.; Nash, J.; Nowell, J.; Przysiezniak, H.; Sciabà, A.; Sedgbeer, J. K.; Thompson, J. C.; Thomson, E.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Buck, P. G.; Ellis, G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Robertson, N. A.; Smizanska, M.; Williams, M. I.; Giehl, I.; Hölldorfer, F.; Jakobs, K.; Kleinknecht, K.; Kröcker, M.; Müller, A.-S.; Nürnberger, H.-A.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; Schmeling, S.; Wachsmuth, H.; Zeitnitz, C.; Ziegler, T.; Bonissent, A.; Carr, J.; Coyle, P.; Ealet, A.; Fouchez, D.; Payre, P.; Rousseau, D.; Tilquin, A.; Aleppo, M.; Antonelli, M.; Gilardoni, S.; Ragusa, F.; Büscher, V.; Dietl, H.; Ganis, G.; Hüttmann, K.; Lütjens, G.; Mannert, C.; Männer, W.; Moser, H.-G.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Azzurri, P.; Boucrot, J.; Callot, O.; Chen, S.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, P.; Jacholkowska, A.; Lefrançois, J.; Serin, L.; Veillet, J.-J.; Videau, I.; de Vivie de Régie, J.-B.; Zerwas, D.; Bagliesi, G.; Boccali, T.; Bozzi, C.; Calderini, G.; Dell'Orso, R.; Ferrante, I.; Giassi, A.; Gregorio, A.; Ligabue, F.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sguazzoni, G.; Tenchini, R.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Coles, J.; Cowan, G.; Green, M. G.; Hutchcroft, D. E.; Jones, L. T.; Medcalf, T.; Strong, J. A.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Norton, P. R.; Tomalin, I. R.; Bloch-Devaux, B.; Colas, P.; Fabbro, B.; Faïf, G.; Lançon, E.; Lemaire, M.-C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Seager, P.; Trabelsi, A.; Tuchming, B.; Vallage, B.; Black, S. N.; Dann, J. H.; Loomis, C.; Kim, H. Y.; Konstantinidis, N.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Cartwright, S.; Combley, F.; Hodgson, P. N.; Lehto, M.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Grupen, C.; Hess, J.; Misiejuk, A.; Prange, G.; Sieler, U.; Borean, C.; Giannini, G.; Gobbo, B.; Putz, J.; Rothberg, J.; Wasserbaech, S.; Williams, R. W.; Armstrong, S. R.; Elmer, P.; Ferguson, D. P. S.; Gao, Y.; González, S.; Hayes, O. J.; Hu, H.; Jin, S.; Kile, J.; McNamara, P. A., III; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; von Wimmersperg-Toeller, J. H.; Wu, S. L.; Wu, X.; Zobernig, G.
2000-04-01
Bose-Einstein correlations are studied in semileptonic (WW-->qq¯lν) and fully hadronic (WW-->qq¯qq¯) W-pair decays with the ALEPH detector at LEP at centre-of-mass energies of 172, 183 and 189 GeV. They are compared with those made at the Z peak after correction for the different flavour compositions. A Monte Carlo model of Bose-Einstein correlations based on the JETSET hadronization scheme was tuned to the Z data and reproduces the correlations in the WW-->qq¯lν events. The same Monte Carlo reproduces the correlations in the WW-->qq¯qq¯ channel assuming independent fragmentation of the two W's. A variant of this model with Bose-Einstein correlations between decay products of different W's is disfavoured.
Einstein-Weyl spaces and third-order differential equations
Tod, K. P.
2000-08-01
The three-dimensional null-surface formalism of Tanimoto [M. Tanimoto, "On the null surface formalism," Report No. gr-qc/9703003 (1997)] and Forni et al. [Forni et al., "Null surfaces formation in 3D," J. Math Phys. (submitted)] are extended to describe Einstein-Weyl spaces, following Cartan [E. Cartan, "Les espaces généralisées et l'integration de certaines classes d'equations différentielles," C. R. Acad. Sci. 206, 1425-1429 (1938); "La geometria de las ecuaciones diferenciales de tercer order," Rev. Mat. Hispano-Am. 4, 1-31 (1941)]. In the resulting formalism, Einstein-Weyl spaces are obtained from a particular class of third-order differential equations. Some examples of the construction which include some new Einstein-Weyl spaces are given.
Black hole merger estimates in Einstein-Maxwell and Einstein-Maxwell-dilaton gravity
Jai-akson, Puttarak; Chatrabhuti, Auttakit; Evnin, Oleg; Lehner, Luis
2017-08-01
The recent birth of gravitational wave astronomy invites a new generation of precision tests of general relativity. Signatures of black hole (BH) mergers must be systematically explored in a wide spectrum of modified gravity theories. Here, we turn to one such theory in which the initial value problem for BH mergers is well posed, the Einstein-Maxwell-dilaton system. We present conservative estimates for the merger parameters (final spins, quasinormal modes) based on techniques that have worked well for ordinary gravity mergers and utilize information extracted from test particle motion in the final BH metric. The computation is developed in parallel for the modified gravity BHs (we specifically focus on the Kaluza-Klein value of the dilaton coupling, for which analytic BH solutions are known) and ordinary Kerr-Newman BHs. We comment on the possibility of obtaining final BHs with spins consistent with current observations.
The Stokes-Einstein relation at moderate Schmidt number.
Balboa Usabiaga, Florencio; Xie, Xiaoyi; Delgado-Buscalioni, Rafael; Donev, Aleksandar
2013-12-07
The Stokes-Einstein relation for the self-diffusion coefficient of a spherical particle suspended in an incompressible fluid is an asymptotic result in the limit of large Schmidt number, that is, when momentum diffuses much faster than the particle. When the Schmidt number is moderate, which happens in most particle methods for hydrodynamics, deviations from the Stokes-Einstein prediction are expected. We study these corrections computationally using a recently developed minimally resolved method for coupling particles to an incompressible fluctuating fluid in both two and three dimensions. We find that for moderate Schmidt numbers the diffusion coefficient is reduced relative to the Stokes-Einstein prediction by an amount inversely proportional to the Schmidt number in both two and three dimensions. We find, however, that the Einstein formula is obeyed at all Schmidt numbers, consistent with linear response theory. The mismatch arises because thermal fluctuations affect the drag coefficient for a particle due to the nonlinear nature of the fluid-particle coupling. The numerical data are in good agreement with an approximate self-consistent theory, which can be used to estimate finite-Schmidt number corrections in a variety of methods. Our results indicate that the corrections to the Stokes-Einstein formula come primarily from the fact that the particle itself diffuses together with the momentum. Our study separates effects coming from corrections to no-slip hydrodynamics from those of finite separation of time scales, allowing for a better understanding of widely observed deviations from the Stokes-Einstein prediction in particle methods such as molecular dynamics.
On the Correct Formulation of the Law of the External Photoelectric Effect
Kalanov, Temur Z.
2017-01-01
The critical and correct scientific analysis of the generally accepted theory of the external photoelectric effect is proposed. The methodological basis for the analysis is the unity of formal logic and of rational dialectics. It is shown that Einstein's formulation of the law of the photoelectric effect is not free from the following objection. The terms of Einstein's formula characterize the quantitative determinacy (i.e., energy) which belongs and is related to the different material objects: ``photon'', ``electron in metal'', and ``electron not in metal''. This signifies that Einstein's formula represents violation of the formal-logical laws of identity and absence (lack) of contradiction. The correct mathematical formulation of the law of the external photoelectric effect within the framework of the system approach is proposed. The correct formulation represents the proportion by relative increments of the energy of the incident photon and the energy of the emitted electron. The proportion describes the linear relationship between the energy of the incident photon and the energy of the emitted electron.
Einstein's legacy the unity of space and time
Schwinger, Julian Seymour
1986-01-01
In this splendidly lucid and profusely illustrated book, a Nobel laureate relates the fascinating story of Einstein, the general and special theories of relativity, and the scientists before and since who influenced relativity's genesis and development. Eschewing technical terms in favor of ordinary language, the book offers a perfect introduction to relativity for readers without specialized knowledge of mathematics and science.The author follows Einstein's own dictum to make explanations ""as simple as possible, but not more so."" His periodic use of equations as points of clarification inv
Einstein's Relativity The Ultimate Key to the Cosmos
Cooperstock, Fred I
2012-01-01
This richly illustrated book is unique in bringing Einstein's relativity to a higher level for the non-specialist than has ever been attempted before, using nothing more than grade-school algebra. Bondi's approach with spacetime diagrams is simplified and expanded, clarifying the famous asymmetric aging-of-twins paradox. Einstein's theory of gravity, general relativity, is simplified for the reader using spacetime diagrams. The theory is applied to important topics in physics such as gravitational waves, gravitational collapse and black holes, time machines, the relationship to the quantum world, galactic motions and cosmology.
Einstein, the Universe, and All That: An Introduction to Relativity
Prescod-Weinstein, Chandra
2011-01-01
Black holes) an expanding universe) space and time inextricably tied together) GPS ... What was this Einstein guy thinking?!? In this tutorial) I'll give an overview of Einstein's theories of relativity and the wild things they say about our Universe. What really happens when a particle crosses an event horizon? What is the future of the Universe? And how can we know it? Wh I'll try to touch on these questions and in so doing) give the talks in the Cosmology) Gravitation and Relativity sessions some context.
On the Einstein-Stern model of rotational heat capacities
DEFF Research Database (Denmark)
Dahl, Jens Peder
1998-01-01
The Einstein-Stern model for the rotational contribution to the heat capacity of a diatomic gas has recently been resuscitated. In this communication, we show that the apparent success of the model is illusory, because it is based on what has turned out to be an unfortunate comparison with experi......The Einstein-Stern model for the rotational contribution to the heat capacity of a diatomic gas has recently been resuscitated. In this communication, we show that the apparent success of the model is illusory, because it is based on what has turned out to be an unfortunate comparison...
On a remarkable electromagnetic field in the Einstein Universe
Kopiński, Jarosław; Natário, José
2017-06-01
We present a time-dependent solution of the Maxwell equations in the Einstein universe, whose electric and magnetic fields, as seen by the stationary observers, are aligned with the Clifford parallels of the 3-sphere S^3. The conformal equivalence between Minkowski's spacetime and (a region of) the Einstein cylinder is then exploited in order to obtain a knotted, finite energy, radiating solution of the Maxwell equations in flat spacetime. We also discuss similar electromagnetic fields in expanding closed Friedmann models, and compute the matter content of such configurations.
Obstructions to the Existence of Sasaki-Einstein Metrics
Gauntlett, J P; Sparks, J; Yau, S T; Gauntlett, Jerome P.; Martelli, Dario; Sparks, James; Yau, Shing-Tung
2007-01-01
We describe two simple obstructions to the existence of Ricci-flat Kahler cone metrics on isolated Gorenstein singularities or, equivalently, to the existence of Sasaki-Einstein metrics on the links of these singularities. In particular, this also leads to new obstructions for Kahler-Einstein metrics on Fano orbifolds. We present several families of hypersurface singularities that are obstructed, including 3-fold and 4-fold singularities of ADE type that have been studied previously in the physics literature. We show that the AdS/CFT dual of one obstruction is that the R-charge of a gauge invariant chiral primary operator violates the unitarity bound.
Albert Einstein, the human side glimpses from his archives
Einstein, Albert; Hoffmann, Banesh
2013-01-01
Modesty, humor, compassion, and wisdom are the traits most evident in this illuminating selection of personal papers from the Albert Einstein Archives. The illustrious physicist wrote as thoughtfully to an Ohio fifth-grader, distressed by her discovery that scientists classify humans as animals, as to a Colorado banker who asked whether Einstein believed in a personal God. Witty rhymes, an exchange with Queen Elizabeth of Belgium about fine music, and expressions of his devotion to Zionism are but some of the highlights found in this warm and enriching book.
Primordial Universe with radiation and Bose-Einstein condensate
Alvarenga, F G; Fracalossi, R; Freitas, R C; Gonçalves, S V B; Monerat, G A; Oliveira-Neto, G; Silva, E V Corrêa
2016-01-01
In this work we derive a scenario where the early Universe consists of radiation and the Bose-Einstein condensate. We have included in our analysis the possibility of gravitational self-interaction due to the Bose-Einstein condensate being attractive or repulsive. After presenting the general structure of our model, we proceed to compute the finite-norm wave packet solutions to the Wheeler-DeWitt equation. The behavior of the scale factor is studied by applying the many-worlds interpretation of quantum mechanics. At the quantum level the cosmological model, in both attractive and repulsive cases, is free from the Big Bang singularity.
From Newton to Einstein: the birth of Special Relativity
Ferraro, Rafael
2007-01-01
Physics was in crisis at the beginning of the twentieth century because the newborn Maxwell's electromagnetism defied mechanistic preconceptions. Albert Einstein understood that the solution to the crisis required an audacious reworking of the concepts of space and time. Special Relativity deeply modified our way of regarding space and time, in order to harmonize electromagnetism with the principle of relativity. As a consequence, lengths and elapsed times were stripped of the invariant character that classical Physics conferred them; in their place, the speed of light acquired that privileged status. Such revolutionary change forced Einstein to reformulate Newtonian mechanics, a step that led him to discover the mass-energy equivalence.
Charged Einstein-aether black holes and Smarr formula
Ding, Chikun; Wang, Anzhong; Wang, Xinwen
2015-10-01
In the framework of the Einstein-Maxwell-aether theory, we present two new classes of exact charged black hole solutions, which are asymptotically flat and possess the universal as well as Killing horizons. We also construct the Smarr formulas and calculate the temperatures of the horizons, using the Smarr mass-area relation. We find that, in contrast to the neutral case, a temperature obtained this way is not proportional to its surface gravity at either of the two types of horizons. Einstein-Maxwell-aether black holes with the cosmological constant and their topological cousins are also presented.
Einstein His Impact on Accelerators; His Impact on the World
Sessler, Andrew M
2005-01-01
The impact of the work of Albert Einstein on accelerator physics is described. Because of the limit of time, and also because the audience knows the details, the impact is described in broad strokes. Nevertheless, it is seen how his work has affected many different aspects of accelerator physics. In the second half of the talk, Albert Einstein's impact on the world will be discussed; namely his work on world peace (including his role as a pacifist, in the atomic bomb, and in arms control) and his efforts as a humanitarian (including his efforts on social justice, anti-racism, and civil rights).
EPR before EPR: A 1930 Einstein-Bohr thought Experiment Revisited
Nikolic, Hrvoje
2012-01-01
In 1930, Einstein argued against the consistency of the time-energy uncertainty relation by discussing a thought experiment involving a measurement of the mass of the box which emitted a photon. Bohr seemingly prevailed over Einstein by arguing that Einstein's own general theory of relativity saves the consistency of quantum mechanics. We revisit…
Brans-Dicke classical cosmology in Einstein frame and metric
Directory of Open Access Journals (Sweden)
H Ghaffarnejad
2013-10-01
Full Text Available Pauli (or Einstein frame is used to study the Brans-Dicke gravity theory, minimally coupled with dilatonic Brans-Dicke scalar field, whose solutions involve degenerate metrics. Some of these solutions exhibit transitions from an Euclidean domain to a Lorentzian space-time corresponding to a spatially flat Robertson-Walker cosmology.
Einstein's Last Dream: The Space–Time Unification of Fundamental ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 1. Einstein's Last Dream: The Space – Time Unification of Fundamental Forces. Abdus Salam. Reflections Volume 3 Issue 1 January 1998 pp 81-88. Fulltext. Click here to view fulltext PDF. Permanent link:
lEinstein's Last Dream: The Space - Time Unification of ...
Indian Academy of Sciences (India)
lEinstein's Last Dream: The Space - Time. Unification of Fundamental Forces. Abdus Salam. 1. From the earliest times, man's dream has been to comprehend the complexity of nature in terms of as few unifying concepts as possible. In this context, in the history of physics, three names stand together; those of Newton, ...
Explosion of a collapsing Bose-Einstein condensate
Duine, R.A.; Stoof, H.T.C.
2001-01-01
We show that elastic collisions between atoms in a Bose-Einstein condensate with attractive interactions can lead to an explosion that ejects a large fraction of the collapsing condensate. We study variationally the dynamics of this explosion and find excellent agreement with recent experiments on
Skyrmions in a ferromagnetic Bose−Einstein condensate
Al Khawaja, U.; Stoof, H.T.C.
2001-01-01
Multi-component Bose-Einstein condensates provide opportunities to explore experimentally the wealth of physics associated with the spin degrees of freedom. The ground-state properties and line-like vortex excitations of these quantum systems have been studied theoretically. In principle,
Explosion of a Collapsing Bose-Einstein Condensate
Duine, R.A.; Stoof, H.T.C.
2000-01-01
we show that elastic collisions between atoms in an Bose-Einstein condensate with attractive interactions lead to an explosion that ejects a large fraction of the collapsing condensate. We study variationally the dynamics of thes explosion and find excellent agreement with recent experiments on
Stochastic dynamics of a trapped Bose-Einstein condensate
Duine, R.A.; Stoof, H.T.C.
2001-01-01
We present a variational solution of the Langevin field equation describing the nonequilibrium dynamics of a harmonically trapped Bose-Einstein condensate. If the thermal cloud remains in equilibrium at all times, we find that the equations of motion for the parameters in our variational ansatz are
Monopoles in an Antiferromagnetic Bose-Einstein Condensate
Stoof, H.T.C.; Vliegen, E.; Al Khawaja, U.
2001-01-01
We show that even in three dimensions an antiferromagnetic spin-1 Bose-Einstein condensate, which can, for instance, be created with 23Na atoms in an optical trap, has not only singular linelike vortex excitations, but also allows for singular pointlike topological excitations, i.e., monopoles
Bose–Einstein condensation: Where many become one and ...
Indian Academy of Sciences (India)
Abstract. Bose–Einstein condensation and superfluidity are well known to occur in the dilute gaseous as well as in the dense liquid state of matter having a fixed number of. Bose particles. Very recently, experimental evidence has been obtained for the probable realization of BEC and superfluidity in 4He in the solid state ...
Einstein relation in compound semiconductors and their nanostructures
Bhattacharya, Sitangshu
2008-01-01
Deals with the Einstein relation in compound semiconductors and their nanostructures. This book considers materials such as nonlinear optical, III-V, ternary, quaternary, II-VI, IV-VI, Bismuth, stressed compounds, quantum wells, quantum wires, nipi structures, carbon nanotubes, heavily doped semiconductors, and inversion layers.
Bose–Einstein condensation: Where many become one and ...
Indian Academy of Sciences (India)
Bose–Einstein condensation and superfluidity are well known to occur in the dilute gaseous as well as in the dense liquid state of matter having a fixed number of Bose particles. Very recently, experimental evidence has been obtained for the probable realization of BEC and superfluidity in 4He in the solid state too, ...
Boltzmann and Einstein: Statistics and dynamics–An unsolved ...
Indian Academy of Sciences (India)
The struggle of Boltzmann with the proper description of the behavior of classical macroscopic bodies in equilibrium in terms of the properties of the particles out of which they consist will be sketched. He used both a dynamical and a statistical method. However, Einstein strongly disagreed with Boltzmann's statistical method ...
Satisfying the Einstein-Podolsky-Rosen criterion with massive particles
DEFF Research Database (Denmark)
Peise, Jan; Kruse, I.; Lange, K.
2016-01-01
In 1935, Einstein, Podolsky and Rosen (EPR) questioned the completeness of quantum mechanics by devising a quantum state of two massive particles with maximally correlated space and momentum coordinates. The EPR criterion qualifies such continuous-variable entangled states, as shown successfully...
Einstein's Riddle as a Tool for Profiling Students
Özeke, Vildan; Akçapina, Gökhan
2016-01-01
There are many computer games, learning environments, online tutoring systems or computerized tools which keeps the track of the user while learning or engaging in the activities. This paper presents results from an exploratory study and aims to group students regarding their behavior data while solving the Einstein's riddle. 45 undergraduate…
Static Solutions of Einstein's Equations with Cylindrical Symmetry
Trendafilova, C. S.; Fulling, S. A.
2011-01-01
In analogy with the standard derivation of the Schwarzschild solution, we find all static, cylindrically symmetric solutions of the Einstein field equations for vacuum. These include not only the well-known cone solution, which is locally flat, but others in which the metric coefficients are powers of the radial coordinate and the spacetime is…
How Einstein Discovered "E[subscript 0] = mc[squared]"
Hecht, Eugene
2012-01-01
This paper traces Einstein's discovery of "the equivalence of mass [m] and energy ["E[subscript 0]"]." He came to that splendid insight in 1905 while employed by the Bern Patent Office, at which time he was not an especially ardent reader of physics journals. How then did the young savant, working outside of academia in semi-isolation, realize…
Albert Einstein-The Man Behind the Myths
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 3; Issue 8. Albert Einstein-The Man Behind the Myths. John Stachel. Reflections Volume 3 Issue 8 August 1998 pp 76-92. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/003/08/0076-0092. Author Affiliations.
Complementarity in the Einstein-Bohr photon box
Dieks, D.G.B.J.; Lam, S
2008-01-01
The Bohr-Einstein photon box thought experiment is a forerunner of the EPR experiment: a packet of radiation escapes from a box, and the box-plus-radiation state remains entangled. Hence, a measurement on the box makes a difference for the state of the far-away radiation long after its escape. This
L'influenza di Einstein sul pensiero di Popper
Directory of Open Access Journals (Sweden)
Carlo Veronesi
2016-12-01
Full Text Available EINSTEIN’S INFLUENCE ON POPPER’S THOUGHT In a BBC radio programme Popper acknowledged his debt to Einstein saying that Einstein’s influence on his thinking was immense and that he mainly made explicit certain points that were implicit in the work of Einstein. In fact, in various writings Einstein presents his critical attitude toward any scientific theory: of particular interest is Einstein’s article «Induktion und Deduktion in der Physik» (1919 that can be considered a concentrate of Popper’s views of science. In the second part of the paper are presented the views of Popper on quantum mechanics and his defense of objectivity and realism. Popper opposes the idea, which he associates with the Copenhagen interpretation, that the theories describing quantum phenomena are about the subjective states of the human observers. Following the lead of Einstein, Popper emphasizes that scientific theories should be interpreted as attempts to describe a mind‐independent reality.
A new solution of Einstein's vacuum field equations
Indian Academy of Sciences (India)
A new solution of Einstein's vacuum field equations is discovered which appears as a generalization of the well-known Ozsváth–Schücking solution and explains its source of curvature which has otherwise remained hidden. Curiously, the new solution has a vanishing Kretschmann scalar and is singularity-free despite ...
Einstein's Tea Leaves and Pressure Systems in the Atmosphere
Tandon, Amit; Marshall, John
2010-01-01
Tea leaves gather in the center of the cup when the tea is stirred. In 1926 Einstein explained the phenomenon in terms of a secondary, rim-to-center circulation caused by the fluid rubbing against the bottom of the cup. This explanation can be connected to air movement in atmospheric pressure systems to explore, for example, why low-pressure…
Parallel Vector Fields and Einstein Equations of Gravity
African Journals Online (AJOL)
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106. Parallel Vector Fields and. Einstein Equations of Gravity. By Isidore Mahara. National University of Rwanda. Department of Applied Mathematics. Abstract. In this paper, we prove that no nontrivial timelike or spacelike parallel vector field exists in a region where the gravitational field created by macroscopic bodies and.
Coset Space Dimensional Reduction of Einstein--Yang--Mills theory
Chatzistavrakidis, A.; Prezas, N.; Zoupanos, G.
2007-01-01
In the present contribution we extend our previous work by considering the coset space dimensional reduction of higher-dimensional Einstein--Yang--Mills theories including scalar fluctuations as well as Kaluza--Klein excitations of the compactification metric and we describe the gravity-modified rules for the reduction of non-abelian gauge theories.
Bright soliton trains of trapped Bose-Einstein condensates
Al Khawaja, U.; Stoof, H.T C; Hulet, R. G.; Strecker, K. E.; Patridge, G.B.
2002-01-01
We variationally determine the dynamics of bright soliton trains composed of harmonically trapped Bose-Einstein condensates with attractive interatomic interactions. In particular, we obtain the interaction potential between two solitons. We also discuss the formation of soliton trains due to the quantum mechanical phase fluctuations of a one-dimensional condensate.
Hydrodynamic excitations in a Bose-Einstein condensate
Meppelink, R
2009-01-01
The field of Bose-Einstein condensation (BEC) in dilute atomic gases provides a fruitful playground to test well-developed theories of quantum fluids. Research using BECs can address open questions relating to the many-body aspects of two-component quantum liquids, namely the interaction between the
A new solution of Einstein's vacuum field equations
Indian Academy of Sciences (India)
Abstract. A new solution of Einstein's vacuum field equations is discovered which appears as a generalization of the well-known Ozsváth–Schücking solution and explains its source of curvature which has otherwise remained hidden. Curiously, the new solution has a vanishing Kretschmann scalar and is singularity-free ...
Parallel Vector Fields and Einstein Equations of Gravity | Mahara ...
African Journals Online (AJOL)
In this paper, we prove that no nontrivial timelike or spacelike parallel vector field exists in a region where the gravitational field created by macroscopic bodies and governed by Einstein's equations does not vanish. In other words, we prove that the existence of such vector fields in a region implies the vanishing of the ...
Productive Learning: Science, Art, and Einstein's Relativity in Educational Reform
Glazek, Stanislaw D.; Sarason, Seymour B.
2006-01-01
Why do people, college-bound or even in college, stay away in droves from courses in science, especially physics? Why do people know so little about the significance of Einstein's contributions which require dramatic changes in how we understand ourselves, our world, and the entire universe? Why have educational reforms failed? In this book, two…
A Conceptual Derivation of Einstein's Postulates of Special Relativity.
Bearden, Thomas E.
This document presents a discussion and conceptual derivation of Einstein's postulates of special relativity. The perceptron approach appears to be a fundamentally new manner of regarding physical phenomena and it is hoped that physicists will interest themselves in the concept. (Author)
The Lorentz Theory of Electrons and Einstein's Theory of Relativity
Goldberg, Stanley
1969-01-01
Traces the development of Lorentz's theory of electrons as applied to the problem of the electrodynamics of moving bodies. Presents evidence that the principle of relativity did not play an important role in Lorentz's theory, and that though Lorentz eventually acknowledged Einstein's work, he was unwilling to completely embrace the Einstein…
The Einstein-Vlasov System/Kinetic Theory
Directory of Open Access Journals (Sweden)
Andréasson Håkan
2005-01-01
Full Text Available The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einsteins equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on nonrelativistic and special relativistic physics, i.e. to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. The Vlasov equation describes matter phenomenologically, and it should be stressed that most of the theorems presented in this article are not presently known for other such matter models (i.e. fluid models. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein-Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to good comprehension of kinetic theory in general relativity.
On Einstein, Light Quanta, Radiation, and Relativity in 1905
Miller, Arthur I.
1976-01-01
Analyzes section 8 of Einstein's relativity paper of 1905, "On the Electrodynamics of Moving Bodies," in its historical context. Relates this section to the rest of the relativity paper, to the genesis of relativity theory, and to contemporaneous work on radiation theory. (Author/MLH)
Two famous results of Einstein derived from the Jarzynski equality
Gittes, Fred
2018-01-01
The Jarzynski equality (JE) is a remarkable statement relating transient irreversible processes to infinite-time free energy differences. Although 20 years old, the JE remains unfamiliar to many; nevertheless, it is a robust and powerful law. We examine two of Einstein's most simple and well-known discoveries, one classical and one quantum, and show how each of these follows from the JE. Our first example is Einstein's relation between the drag and diffusion coefficients of a particle in Brownian motion. In this context, we encounter a paradox in the macroscopic limit of the JE which is fascinating but also warns us against using the JE too freely outside of the microscopic domain. Our second example is the equality of Einstein's B coefficients for absorption and stimulated emission of quanta. Here, resonant light does irreversible work on a sample, and the argument differs from Einstein's equilibrium reasoning using the Planck black-body spectrum. We round out our examples with a brief derivation and discussion of Jarzynski's remarkable equality.
Bright soliton trains of trapped Bose-Einstein condensates
Al Khawaja, U.; Stoof, H.T.C.; Hulet, R.G.; Strecker, K.E.; Patridge, G.B.
2002-01-01
We variationally determine the dynamics of bright soliton trains composed of harmonically trapped Bose-Einstein condensates with attractive interatomic interactions. In particular, we obtain the interaction potential between two solitons. We also discuss the formation of soliton trains due to the
The 2001 Nobel Prize in Physics-Bose–Einstein Condensation
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 1. The 2001 Nobel Prize in Physics - Bose–Einstein Condensation. Vasant Natarajan. General Article Volume 7 Issue 1 January 2002 pp 23-30. Fulltext. Click here to view fulltext PDF. Permanent link:
How Einstein Discovered the Special Theory of Relativity
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 2. How Einstein Discovered the Special Theory of Relativity. Sriranjan Banerji. General Article Volume 11 Issue 2 February 2006 pp 27-42. Fulltext. Click here to view fulltext PDF. Permanent link:
Atom Optics for Bose-Einstein Condensates (BEC)
2012-04-25
CONTRACT NUMBER Atom Optics for Bose-Einstein Condensates (BEC) 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Matthew B...free space fountain and beam configurations, that utilize light pulses to manipulate the atoms, have demonstrated the greatest sensitivities [1, 2, 3
Subterranean ground motion studies for the Einstein Telescope
Beker, M.G.; van den Brand, J.F.J.; Rabeling, D.S.
2015-01-01
Seismic motion limits the low-frequency sensitivity of ground-based gravitational wave detectors. A conceptual design study into the feasibility of a future-generation gravitational wave observatory, coined the Einstein Telescope, has been completed. As part of this design phase, we performed a
Parallel Vector Fields and Einstein Equations of Gravity
African Journals Online (AJOL)
user
107. This paper uses Einstein equations of General Relativity as presented for example in Landau and Lifchitz and standard theorems of Differential. Geometry as presented, for example in Sternberg [3]. 2. Parallel vector fields on Riemannian manifolds. Let M be an n-dimensional Riemannian manifold with metric tensor g.
Enhanced factoring with a bose-einstein condensate.
Sadgrove, Mark; Kumar, Sanjay; Nakagawa, Ken'ichi
2008-10-31
We present a novel method to realize analog sum computation with a Bose-Einstein condensate in an optical lattice potential subject to controlled phase jumps. We use the method to implement the Gauss sum algorithm for factoring numbers. By exploiting higher order quantum momentum states, we are able to improve the algorithm's accuracy beyond the limits of the usual classical implementation.
Space and Time: From Antiquity to Einstein and Beyond
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 9. Space and Time: From Antiquity to Einstein and Beyond ... Institute for Gravitational Physics and Geometry Physics Department Penn State, University Park PA 16802, USA. Inter-University Centre for Astronomy and Astrophysics Post Bag 4, ...
Resonant tunneling of Bose-Einstein condensates in optical lattices
Energy Technology Data Exchange (ETDEWEB)
Zenesini, Alessandro; Sias, Carlo; Lignier, Hans; Singh, Yeshpal; Ciampini, Donatella; Morsch, Oliver; Mannella, Riccardo; Arimondo, Ennio [Dipartimento di Fisica Enrico Fermi, Universita degli Studi di Pisa, Largo Pontecorvo 3, I-56127 Pisa (Italy); Tomadin, Andrea [Scuola Normale Superiore, Piazza dei Cavalieri 7, I-56126 Pisa (Italy); Wimberger, Sandro [Institut fuer Theoretische Physik, Universitaet Heidelberg, Philosophenweg 19, D-69120 Heidelberg (Germany)], E-mail: s.wimberger@thphys.uni-heidelberg.de
2008-05-15
In this paper, we present the theoretical as well as experimental results on resonantly enhanced tunneling of Bose-Einstein condensates in optical lattices both in the linear case and for small nonlinearities. Our results demonstrate the usefulness of condensates in optical lattices for simulating Hamiltonians originally used for describing solid-state phenomena.
Resonant tunneling of Bose-Einstein condensates in optical lattices
Zenesini, Alessandro; Sias, Carlo; Lignier, Hans; Singh, Yeshpal; Ciampini, Donatella; Morsch, Oliver; Mannella, Riccardo; Arimondo, Ennio; Tomadin, Andrea; Wimberger, Sandro
2007-01-01
In this article, we present theoretical as well as experimental results on resonantly enhanced tunneling of Bose-Einstein condensates in optical lattices both in the linear case and for small nonlinearities. Our results demonstrate the usefulness of condensates in optical lattices for simulating Hamiltonians originally used for describing solid state phenomena.
Boltzmann and Einstein: Statistics and dynamics – An unsolved ...
Indian Academy of Sciences (India)
Boltzmann and Einstein: Statistics and dynamics –. An unsolved problem. E G D COHEN. The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA. E-mail: egdc@rockefeller.edu. Abstract. The struggle of Boltzmann with the proper description of the behavior of classical macroscopic bodies in equilibrium in ...
Introduction to Einstein-Maxwell equations and the Rainich conditions
Santos, Wytler Cordeiro dos
2016-01-01
The first results of Einstein-Maxwell equations established by Raincih in 1925 are therefore called the Raincih conditions. Later the result was rediscovered by Misner and Wheeler in 1957 and made the basis of their geometrodynamics. The present survey will consider didactically the curvature of spacetime attributed to an electromagnetic field with conceptual and calculational details.
Self-dual Einstein spaces, heavenly metrics, and twistors
Alexandrov, S.; Pioline, B.; Vandoren, S.J.G.|info:eu-repo/dai/nl/304830739
2010-01-01
Four-dimensional quaternion-Kähler metrics, or equivalently self-dual Einstein spaces M, are known to be encoded locally into one real function h subject to Przanowski’s heavenly equation. We elucidate the relation between this description and the usual twistor description for quaternion-Kähler
100 years of Einstein's Theory of Brownian Motion: From Pollen ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 11. 100 years of Einstein's Theory of Brownian Motion: From Pollen Grains to Protein Trains – 2. Debashish Chowdhury. General Article Volume 10 Issue 11 November 2005 pp 42-54 ...
100 years of Einstein's Theory of Brownian Motion: from Pollen ...
Indian Academy of Sciences (India)
Home; Journals; Resonance – Journal of Science Education; Volume 10; Issue 9. 100 Years of Einstein's Theory of Brownian Motion: from Pollen Grains to Protein Trains – 1. Debashish Chowdhury. General Article Volume 10 Issue 9 September 2005 pp 63-78 ...
Albert Einstein's Personal Papers: A Physics Teaching Resource.
Derman, Samuel
2000-01-01
Presents the concept of using Einstein the man as a way of generating interest in the study of physics among students. Finds that it provides an instantly recognizable face for science, thus a gateway to the subject through the discussion of the man. (Author/CCM)
Albert Einstein and LD: An Evaluation of the Evidence.
Thomas, Marlin
2000-01-01
This article refutes claims that Albert Einstein had a learning disability and argues the claim derives its force not from evidence but from belief that the greatest among us suffer from some impairment and from desire to enhance the status of a marginalized group by including exceptional individuals. (Contains references.) (Author/CR)
Reflections The Early life of Albert Einstein: Seeking the Mature ...
Indian Academy of Sciences (India)
was his introduction to music. Albert's mother Pauline, nee Koch, came from a. Stuttgart family of grain merchants with a comfortable financial background. She was a lover and a keen student of classical music and from his sixth year onwards Einstein took lessons on the violin. Early on it may have been a chore but soon he ...
Beyond Einstein: From the Big Bang to Black Holes
2005-01-01
How did the Universe begin? Does time have a beginning and an end? Does space have edges? The questions are clear and simple. They are as old as human curiosity. But the answers have always seemed beyond the reach of science. Until now. In their attempts to understand how space, time, and matter are connected, Einstein and his successors made three predictions. First, space is expanding from a Big Bang; second, space and time can tie themselves into contorted knots called black holes where time actually comes to a halt; third, space itself contains some kind of energy that is pull- ing the Universe apart. Each of these three predictions seemed so fantastic when it was made that everyone, including Einstein himself, regarded them as unlikely. Incredibly, all three have turned out to be true. Yet Einstein's legacy is one of deep mystery, because his theories are silent on three questions raised by his fantastic predictions: (1) What powered the Big Bang? (2) What happens to space, time, and matter at the edge of a black hole? (3) What is the mysterious dark energy pulling the Universe apart? The answers to these questions-which lie at the crux of where our current theories fail us-will lead to a profound, new understanding of the nature of time and space. To find answers, however, we must venture beyond Einstein. The answers require new theories, such as the inflationary Universe and new insights in high-energy particle theory. Like Einstein s theories, these make fantastic predictions that seem hard to believe: unseen dimensions and entire universes beyond our own. We must find facts to confront and guide these new theories. Powerful new technologies now make this possible. And NASA and its partners are developing an armada of space-based observatories to chart the path to discovery. Here is where the Beyond Einstein story begins. By exploring the three questions that are Einstein s legacy, we begin the next revolution in understanding our Universe. We plot our way
Albert Einstein and his mentor Max Talmey. The seventh Charles B. Snyder Lecture.
Ravin, J G
1997-01-01
While he was a student at the Munich medical school, Max Talmey strongly influenced the education of Albert Einstein. Their association occurred during five years of Einstein's second decade. They lost contact for many years after each left Munich. Talmey emigrated to the United States and practiced medicine, mainly ophthalmology, in New York City. He made significant contributions to medicine, to the popularization of Einstein's work, and to the development of international languages. The relationship of Talmey and Einstein was rekindled when Einstein visited and later moved to the United States.
Einstein*s witches* sabbath in Brussels: The legend and the facts
Lambert, Franklin J.
2015-09-01
This paper is about the first Solvay Council on Physics, its surprising origin and its far reaching consequences. In spite of the various accounts that have been given by several authors - they include historians of science, but also outstanding scientists, such as Leon Rosenfeld, Niels Bohr and Eduardo Amaldi - it appears that only limited attention was paid so far to the more singular aspects of this legendary meeting, and to the peculiar circumstances which led to its convening. This fact may be due to the restricted availability of relevant documents, many of which are located in different archives. It also reflects the rather abstract character of Ernest Solvay*s Institute of Physics - an Institute without a permanent staff, governed by geographically separated bodies: a scientific committee with a chairman in Haarlem, a secretary in Copenhagen and an administrative committee in Brussels. One of the purposes of the paper is to fill this gap by revisiting the course of events which led to Solvay*s invitation of June 1911. Another aim is to present a brief, yet balanced, account of the deliberations which took place in October-November 1911, by pointing at some elements that may be regarded as highlights of the Council, and by focusing on the contrasting aspects of its main results: the contrast between the Council*s disappointing conclusions on the one hand, and its positive consequences on the other hand. Special attention in this context is given to the unexpected concern about the validity of Planck*s law, expressed by Emil Warburg, and to the apparent contradictions in Einstein*s private reactions to the outcome of the Brussels meeting. The paper also aims at restoring the truth about some facts regarding the Solvay reports and their discussion, by revealing the discrepancies between the official account - the Gauthier-Villars volume "La théorie du rayonnement et les quanta", published in 1912, and the actual proceedings of the conference, based on notes
Continuum and Discrete Initial-Boundary Value Problems and Einstein's Field Equations
Directory of Open Access Journals (Sweden)
Olivier Sarbach
2012-08-01
Full Text Available Many evolution problems in physics are described by partial differential equations on an infinite domain; therefore, one is interested in the solutions to such problems for a given initial dataset. A prominent example is the binary black-hole problem within Einstein's theory of gravitation, in which one computes the gravitational radiation emitted from the inspiral of the two black holes, merger and ringdown. Powerful mathematical tools can be used to establish qualitative statements about the solutions, such as their existence, uniqueness, continuous dependence on the initial data, or their asymptotic behavior over large time scales. However, one is often interested in computing the solution itself, and unless the partial differential equation is very simple, or the initial data possesses a high degree of symmetry, this computation requires approximation by numerical discretization. When solving such discrete problems on a machine, one is faced with a finite limit to computational resources, which leads to the replacement of the infinite continuum domain with a finite computer grid. This, in turn, leads to a discrete initial-boundary value problem. The hope is to recover, with high accuracy, the exact solution in the limit where the grid spacing converges to zero with the boundary being pushed to infinity. The goal of this article is to review some of the theory necessary to understand the continuum and discrete initial boundary-value problems arising from hyperbolic partial differential equations and to discuss its applications to numerical relativity; in particular, we present well-posed initial and initial-boundary value formulations of Einstein's equations, and we discuss multi-domain high-order finite difference and spectral methods to solve them.
Einstein's quantum theory of the monatomic ideal gas: non-statistical arguments for a new statistics
Pérez, Enric
2010-01-01
In this article, we analyze the third of three papers, in which Einstein presented his quantum theory of the ideal gas of 1924-1925. Although it failed to attract the attention of Einstein's contemporaries and although also today very few commentators refer to it, we argue for its significance in the context of Einstein's quantum researches. It contains an attempt to extend and exhaust the characterization of the monatomic ideal gas without appealing to combinatorics. Its ambiguities illustrate Einstein's confusion with his initial success in extending Bose's results and in realizing the consequences of what later became to be called Bose-Einstein statistics. We discuss Einstein's motivation for writing a non-combinatorial paper, partly in response to criticism by his friend Ehrenfest, and we paraphrase its content. Its arguments are based on Einstein's belief in the complete analogy between the thermodynamics of light quanta and of material particles and invoke considerations of adiabatic transformations as ...
Energy Technology Data Exchange (ETDEWEB)
Kimishima, Yoshihide [Yokohama National University, Kanagawa (Japan). Faculty of Engineering
1998-11-25
In 'letter to Kamerilingh Onnes from the Hantaro Nagaoka', Einstein inspected the He liquefier in the university in 1920. At that time, cooled sample tried to investigate the possibility of the academic alternating current of the fact between reason and Honda Kotaro teacher and Kamerilingh Onnes described Honda Kotaro teacher Ni steel. (NEDO)
Assessment of strategy formulation
DEFF Research Database (Denmark)
Acur, Nuran; Englyst, Linda
2006-01-01
Purpose – Today, industrial firms need to cope with competitive challenges related to innovation, dynamic responses, knowledge sharing, etc. by means of effective and dynamic strategy formulation. In light of these challenges, the purpose of the paper is to present and evaluate an assessment tool...... for strategy formulation processes that ensures high quality in process and outcome. Design/methodology/approach – A literature review was conducted to identify success criteria for strategy formulation processes. Then, a simple questionnaire and assessment tool was developed and used to test the validity...... of the success criteria through face-to-face interviews with 46 managers, workshops involving 40 managers, and two in-depth case studies. The success criteria have been slightly modified due to the empirical results, to yield the assessment tool. Findings – The resulting assessment tool integrates three generic...
Grundmann, Siegfried
Referring to the Straus-Herrmann correspondence, we deal only with one aspect of the ``political Einstein'': his attitude towards Marx, Engels, Lenin and Stalin (who were in the past sometimes called the ``classics of Marxism-Leninism''). Einstein revered Marx, but condemned Stalin as a criminal. He also resisted attempts to be misused by representatives of ``dialectic materialism''.
Einstein-Yang-Mills from pure Yang-Mills amplitudes
Energy Technology Data Exchange (ETDEWEB)
Nandan, Dhritiman; Plefka, Jan [Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin,Zum Großen Windkanal 6, D-12489 Berlin (Germany); Schlotterer, Oliver [Max-Planck-Institut für Gravitationsphysik, Albert-Einstein-Institut,Am Mühlenberg 1, D-14476 Potsdam (Germany); Wen, Congkao [I.N.F.N. Sezione di Roma Tor Vergata,Via della Ricerca Scientifica, 00133 Roma (Italy)
2016-10-14
We present new relations for scattering amplitudes of color ordered gluons and gravitons in Einstein-Yang-Mills theory. Tree-level amplitudes of arbitrary multiplicities and polarizations involving up to three gravitons and up to two color traces are reduced to partial amplitudes of pure Yang-Mills theory. In fact, the double-trace identities apply to Einstein-Yang-Mills extended by a dilaton and a B-field. Our results generalize recent work of Stieberger and Taylor for the single graviton case with a single color trace. As the derivation is made in the dimension-agnostic Cachazo-He-Yuan formalism, our results are valid for external bosons in any number of spacetime dimensions. Moreover, they generalize to the superamplitudes in theories with 16 supercharges.
The Einstein Toolkit: A Community Computational Infrastructure for Relativistic Astrophysics
Löffler, Frank; Bentivegna, Eloisa; Bode, Tanja; Diener, Peter; Haas, Roland; Hinder, Ian; Mundim, Bruno C; Ott, Christian D; Schnetter, Erik; Allen, Gabrielle; Campanelli, Manuela; Laguna, Pablo
2011-01-01
We describe the Einstein Toolkit, a community-driven, freely accessible computational infrastructure intended for use in numerical relativity, relativistic astrophysics, and other applications. The Toolkit, developed by a collaboration involving researchers from multiple institutions around the world, combines a core set of components needed to simulate astrophysical objects such as black holes, compact objects, and collapsing stars, as well as a full suite of analysis tools. The Einstein Toolkit is currently based on the Cactus Framework for high-performance computing and the Carpet adaptive mesh refinement driver. It implements spacetime evolution via the BSSN evolution system and general-relativistic hydrodynamics in a finite-volume discretization. The toolkit is under continuous development and contains many new code components that have been publicly released for the first time and are described in this article. We discuss the motivation behind the release of the toolkit, the philosophy underlying its de...
TV News Magazine Presentation: Einstein by Schweizer Fernsehen (2009)
CERN Bulletin
2011-01-01
In this episode of Einstein, students from the University of Zurich explain the LHC physics experiments with chocolate and coffee cups. Using these ordinary items, the young researchers demonstrate what happens when two protons collide and how they are measured and detected. They also visit the CMS and LHCb detectors. Other topics in this episode include studies of crash test dummies to determine the right kind of protection needed for winter sports, such as skiing and snowboarding; image researchers at the University of Zurich poll people on the effects of image verses hard facts; the enormous potential of LED lights as the source of light for the future; and scientists determine that our closest ancestors are not the chimpanzee or orangutan, but the common marmoset. Due to room issues last time, Einstein will be presented on Friday, 11 February from 13:00 to 14:00 in the Council Chamber Language: German
Einstein contra Aristotle: The sound from the heavens
Neves, J. C. S.
2017-09-01
In "On the Heavens" Aristotle criticizes the Pythagorean point of view which claims the existence of a cosmic music and a cosmic sound. According to the Pythagorean argument, there exists a cosmic music produced by stars and planets. These celestial bodies generate sound in its movements, and the music appears due to the cosmic harmony. For Aristotle, there is no sound produced by celestial bodies. Then, there is no music as well. However, recently, LIGO (Laser Interferometer Gravitational-Waves Observatory) has detected the gravitational waves predicted by Einstein. In some sense, a sound originated from black holes has been heard. That is, Einstein or the General Relativity and LIGO appear to be with the Pythagoreanism and against the master of the Lyceum.
Bose-Einstein correlations in W-pair decays
Barate, R; Ghez, P; Goy, C; Jézéquel, S; Lees, J P; Martin, F; Merle, E; Minard, M N; Pietrzyk, B; Alemany, R; Bravo, S; Casado, M P; Chmeissani, M; Crespo, J M; Fernández, E; Fernández-Bosman, M; Garrido, L; Graugès-Pous, E; Juste, A; Martínez, M; Merino, G; Miquel, R; Mir, L M; Morawitz, P; Pacheco, A; Riu, I; Ruiz, H; Colaleo, A; Creanza, D; De Palma, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Boix, G; Buchmüller, O L; Cattaneo, M; Cerutti, F; Ciulli, V; Davies, G; Dissertori, G; Drevermann, H; Forty, Roger W; Frank, M; Gianotti, F; Greening, T C; Halley, A W; Hansen, J B; Harvey, J; Janot, P; Jost, B; Kado, M; Leroy, O; Maley, P; Mato, P; Minten, Adolf G; Moutoussi, A; Ranjard, F; Rolandi, Luigi; Schlatter, W D; Schmitt, M; Schneider, O; Spagnolo, P; Tejessy, W; Teubert, F; Tournefier, E; Valassi, Andrea; Wright, A E; Ajaltouni, Ziad J; Badaud, F; Chazelle, G; Deschamps, O; Dessagne, S; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Pascolo, J M; Perret, P; Podlyski, F; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Vayaki, Anna; Blondel, A; Brient, J C; Machefert, F P; Rougé, A; Swynghedauw, M; Tanaka, R; Videau, H L; Focardi, E; Parrini, G; Zachariadou, K; Corden, M; Georgiopoulos, C H; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Chalmers, M; Kennedy, J; Lynch, J G; Negus, P; O'Shea, V; Räven, B; Smith, D; Teixeira-Dias, P; Thompson, A S; Ward, J J; Cavanaugh, R J; Dhamotharan, S; Geweniger, C; Hanke, P; Hepp, V; Kluge, E E; Leibenguth, G; Putzer, A; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Marinelli, N; Martin, E B; Nash, J; Nowell, J; Przysiezniak, H; Sciabà, A; Sedgbeer, J K; Thompson, J C; Thomson, E; Williams, M D; Ghete, V M; Girtler, P; Kneringer, E; Kuhn, D; Rudolph, G; Bowdery, C K; Buck, P G; Ellis, G; Finch, A J; Foster, F; Hughes, G; Jones, R W L; Robertson, N A; Smizanska, M; Williams, M I; Giehl, I; Hölldorfer, F; Jakobs, K; Kleinknecht, K; Kröcker, M; Müller, A S; Nürnberger, H A; Quast, G; Renk, B; Rohne, E; Sander, H G; Schmeling, S; Wachsmuth, H W; Zeitnitz, C; Ziegler, T; Aubert, Jean-Jacques; Bonissent, A; Carr, J; Coyle, P; Ealet, A; Fouchez, D; Tilquin, A; Aleppo, M; Antonelli, M; Gilardoni, S S; Ragusa, F; Büscher, V; Dietl, H; Ganis, G; Hüttmann, K; Lütjens, G; Mannert, C; Männer, W; Moser, H G; Schael, S; Settles, Ronald; Seywerd, H C J; Stenzel, H; Wiedenmann, W; Wolf, G; Azzurri, P; Boucrot, J; Callot, O; Chen, S; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacholkowska, A; Lefrançois, J; Serin, L; Veillet, J J; Videau, I; De Vivie de Régie, J B; Zerwas, D; Bagliesi, G; Boccali, T; Bozzi, C; Calderini, G; Dell'Orso, R; Ferrante, I; Giassi, A; Gregorio, A; Ligabue, F; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Rizzo, G; Sanguinetti, G; Sguazzoni, G; Tenchini, Roberto; Venturi, A; Verdini, P G; Blair, G A; Coles, J; Cowan, G D; Green, M G; Hutchcroft, D E; Jones, L T; Medcalf, T; Strong, J A; Botterill, David R; Clifft, R W; Edgecock, T R; Norton, P R; Tomalin, I R; Bloch-Devaux, B; Colas, P; Fabbro, B; Faïf, G; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Rosowsky, A; Seager, P; Trabelsi, A; Tuchming, B; Vallage, B; Black, S N; Dann, J H; Loomis, C; Kim, H Y; Konstantinidis, N P; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Cartwright, S L; Combley, F; Hodgson, P N; Lehto, M H; Thompson, L F; Affholderbach, K; Böhrer, A; Brandt, S; Grupen, Claus; Hess, J; Misiejuk, A; Prange, G; Sieler, U; Borean, C; Giannini, G; Gobbo, B; Pütz, J; Rothberg, J E; Wasserbaech, S R; Williams, R W; Armstrong, S R; Elmer, P; Ferguson, D P S; Gao, Y; González, S; Hayes, O J; Hu, H; Jin, S; Kile, J; McNamara, P A; Nielsen, J; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Von Wimmersperg-Töller, J H; Wu Sau Lan; Wu, X; Zobernig, G
2000-01-01
Bose-Einstein correlations are studied in semileptonicWW --> qqbarlnu and fully hadronic WW --> qqbarqqbar W-pair decays with the ALEPH detector at LEP at centre-of-mass energies of 172, 183 and 189GeV. They are compared with those made at the Z peak after correction for the different flavour compositions. A Monte Carlo model of Bose-Einsteincorrelations based on the JETSET hadronization scheme was tuned to the Z data and reproduces the correlations in the WW --> qqbarlnu events. The same Monte Carlo reproduces the correlations in the WW --> qqbarqqbarchannel assuming independent fragmentation of the two W's. A variant thismodel with Bose-Einstein correlations between decay products of different W's is disfavoured.
Theorems on Existence and Global Dynamics for the Einstein Equations
Directory of Open Access Journals (Sweden)
Rendall Alan
2002-01-01
Full Text Available This article is a guide to theorems on existence and global dynamics of solutions ofthe Einstein equations. It draws attention to open questions in the field. The local-in-time Cauchy problem, which is relatively well understood, is surveyed. Global results for solutions with various types of symmetry are discussed. A selection of results from Newtonian theory and special relativity that offer useful comparisons is presented. Treatments of global results in the case of small data and results on constructing spacetimes with prescribed singularity structure are given. A conjectural picture of the asymptotic behaviour of general cosmological solutions of the Einstein equations is built up. Some miscellaneous topics connected with the main theme are collected in a separate section.
Interferometry with Bose-Einstein condensates in microgravity.
Müntinga, H; Ahlers, H; Krutzik, M; Wenzlawski, A; Arnold, S; Becker, D; Bongs, K; Dittus, H; Duncker, H; Gaaloul, N; Gherasim, C; Giese, E; Grzeschik, C; Hänsch, T W; Hellmig, O; Herr, W; Herrmann, S; Kajari, E; Kleinert, S; Lämmerzahl, C; Lewoczko-Adamczyk, W; Malcolm, J; Meyer, N; Nolte, R; Peters, A; Popp, M; Reichel, J; Roura, A; Rudolph, J; Schiemangk, M; Schneider, M; Seidel, S T; Sengstock, K; Tamma, V; Valenzuela, T; Vogel, A; Walser, R; Wendrich, T; Windpassinger, P; Zeller, W; van Zoest, T; Ertmer, W; Schleich, W P; Rasel, E M
2013-03-01
Atom interferometers covering macroscopic domains of space-time are a spectacular manifestation of the wave nature of matter. Because of their unique coherence properties, Bose-Einstein condensates are ideal sources for an atom interferometer in extended free fall. In this Letter we report on the realization of an asymmetric Mach-Zehnder interferometer operated with a Bose-Einstein condensate in microgravity. The resulting interference pattern is similar to the one in the far field of a double slit and shows a linear scaling with the time the wave packets expand. We employ delta-kick cooling in order to enhance the signal and extend our atom interferometer. Our experiments demonstrate the high potential of interferometers operated with quantum gases for probing the fundamental concepts of quantum mechanics and general relativity.
The Einstein-Vlasov System/Kinetic Theory
Directory of Open Access Journals (Sweden)
Håkan Andréasson
2011-05-01
Full Text Available The main purpose of this article is to provide a guide to theorems on global properties of solutions to the Einstein-Vlasov system. This system couples Einstein’s equations to a kinetic matter model. Kinetic theory has been an important field of research during several decades in which the main focus has been on non-relativistic and special relativistic physics, i.e., to model the dynamics of neutral gases, plasmas, and Newtonian self-gravitating systems. In 1990, Rendall and Rein initiated a mathematical study of the Einstein-Vlasov system. Since then many theorems on global properties of solutions to this system have been established. This paper gives introductions to kinetic theory in non-curved spacetimes and then the Einstein–Vlasov system is introduced. We believe that a good understanding of kinetic theory in non-curved spacetimes is fundamental to a good comprehension of kinetic theory in general relativity.
Theorems on Existence and Global Dynamics for the Einstein Equations
Directory of Open Access Journals (Sweden)
Rendall Alan D.
2005-10-01
Full Text Available This article is a guide to theorems on existence and global dynamics of solutions of the Einstein equations. It draws attention to open questions in the field. The local-in-time Cauchy problem, which is relatively well understood, is surveyed. Global results for solutions with various types of symmetry are discussed. A selection of results from Newtonian theory and special relativity that offer useful comparisons is presented. Treatments of global results in the case of small data and results on constructing spacetimes with prescribed singularity structure or late-time asymptotics are given. A conjectural picture of the asymptotic behaviour of general cosmological solutions of the Einstein equations is built up. Some miscellaneous topics connected with the main theme are collected in a separate section.
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.
Gravitational catalysis of merons in Einstein-Yang-Mills theory
Canfora, Fabrizio; Oh, Seung Hun; Salgado-Rebolledo, Patricio
2017-10-01
We construct regular configurations of the Einstein-Yang-Mills theory in various dimensions. The gauge field is of meron-type: it is proportional to a pure gauge (with a suitable parameter λ determined by the field equations). The corresponding smooth gauge transformation cannot be deformed continuously to the identity. In the three-dimensional case we consider the inclusion of a Chern-Simons term into the analysis, allowing λ to be different from its usual value of 1 /2 . In four dimensions, the gravitating meron is a smooth Euclidean wormhole interpolating between different vacua of the theory. In five and higher dimensions smooth meron-like configurations can also be constructed by considering warped products of the three-sphere and lower-dimensional Einstein manifolds. In all cases merons (which on flat spaces would be singular) become regular due to the coupling with general relativity. This effect is named "gravitational catalysis of merons".
The Spacetime Between Einstein and Kaluza-Klein: Further Explorations
Vuille, Chris
2017-01-01
Tensor multinomials can be used to create a generalization of Einstein's general relativity that in a mathematical sense falls between Einstein's original theory in four dimensions and the Kaluza-Klein theory in five dimensions. In the extended theory there are only four physical dimensions, but the tensor multinomials are expanded operators that can accommodate other forces of nature. The equivalent Ricci tensor of this geometry yields vacuum general relativity and electromagnetism, as well as a Klein-Gordon-like quantum scalar field. With a generalization of the stress-energy tensor, an exact solution for a plane-symmetric dust can be found where the scalar portion of the field drives early universe inflation, levels off for a period, then causes a later continued universal acceleration, a possible geometric mechanism for the inflaton or dark energy. Some new explorations of the equations, the problems, and possibilities will be presented and discussed.
Sharp asymptotics for Einstein-$\\lambda$-dust flows
Friedrich, Helmut
2016-01-01
We consider the Einstein-dust equations with positive cosmological constant $\\lambda$ on manifolds with time slices diffeomorphic to an orientable, compact 3-manifold $S$. It is shown that the set of standard Cauchy data for the Einstein-$\\lambda$-dust equations on $S$ contains an open (in terms of suitable Sobolev norms) subset of data that develop into solutions which admit at future time-like infinity a space-like conformal boundary ${\\cal J}^+$ that is $C^{\\infty}$ if the data are of class $C^{\\infty}$ and of correspondingly lower smoothness otherwise. As a particular case follows a strong stability result for FLRW solutions. The solutions can conveniently be characterized in terms of their asymptotic end data induced on ${\\cal J}^+$, only a linear equation must be solved to construct such data. In the case where the energy density $\\hat{\\rho}$ is everywhere positive such data can be constructed without solving any differential equation at all.
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.
Scalar field as a Bose-Einstein condensate?
Energy Technology Data Exchange (ETDEWEB)
Castellanos, Elías; Escamilla-Rivera, Celia [Mesoamerican Centre for Theoretical Physics (ICTP regional headquarters in Central America, the Caribbean and Mexico), Universidad Autónoma de Chiapas, Carretera Zapata Km. 4, Real del Bosque (Terán), 29040, Tuxtla Gutiérrez, Chiapas (Mexico); Macías, Alfredo [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, A.P. 55-534, Mexico D.F. 09340 (Mexico); Núñez, Darío, E-mail: ecastellanos@mctp.mx, E-mail: cescamilla@mctp.mx, E-mail: amac@xanum.uam.mx, E-mail: nunez@nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C.U., A.P. 70-543, México D.F. 04510 (Mexico)
2014-11-01
We discuss the analogy between a classical scalar field with a self-interacting potential, in a curved spacetime described by a quasi-bounded state, and a trapped Bose-Einstein condensate. In this context, we compare the Klein-Gordon equation with the Gross-Pitaevskii equation. Moreover, the introduction of a curved background spacetime endows, in a natural way, an equivalence to the Gross-Pitaevskii equation with an explicit confinement potential. The curvature also induces a position dependent self-interaction parameter. We exploit this analogy by means of the Thomas-Fermi approximation, commonly used to describe the Bose-Einstein condensate, in order to analyze the quasi bound scalar field distribution surrounding a black hole.
How Einstein Created Relativity out of Physics and Astronomy
Topper, David
2013-01-01
This book tracks the history of the theory of relativity through Einstein’s life, with in-depth studies of its background as built upon by ideas from earlier scientists. The focus points of Einstein’s theory of relativity include its development throughout his life; the origins of his ideas and his indebtedness to the earlier works of Galileo, Newton, Faraday, Mach and others; the application of the theory to the birth of modern cosmology; and his quest for a unified field theory. Treading a fine line between the technical and popular (but not shying away from the occasional equation), this book explains the entire range of relativity and weaves an up-to-date biography of Einstein throughout. The result is an explanation of the world of relativity, based on an extensive journey into earlier physics and a simultaneous voyage into the mind of Einstein, written for the curious and intelligent reader.
Sharp Asymptotics for Einstein-{λ}-Dust Flows
Friedrich, Helmut
2017-03-01
We consider the Einstein-dust equations with positive cosmological constant {λ} on manifolds with time slices diffeomorphic to an orientable, compact 3-manifold {S}. It is shown that the set of standard Cauchy data for the Einstein-{λ}-dust equations on {S} contains an open (in terms of suitable Sobolev norms) subset of data which develop into solutions that admit at future time-like infinity a space-like conformal boundary J^+ that is C^{∞} if the data are of class C^{∞} and of correspondingly lower smoothness otherwise. The class of solutions considered here comprises non-linear perturbations of FLRW solutions as very special cases. It can conveniently be characterized in terms of asymptotic end data induced on J^+. These data must only satisfy a linear differential equation. If the energy density is everywhere positive they can be constructed without solving differential equations at all.
Network computing with Einstein@home and climateprediction.net
CERN. Geneva; Christensen, Carl; Massey, Neil; Aina, Tolu; Marquina, Miguel Angel
2005-01-01
Einstein@Home is a project developed to search data from the Laser Interferometer Gravitational wave Observatory (LIGO) in the US and from the GEO 600 gravitational wave observatory in Germany for signals coming from extremely dense, rapidly rotating stars. Such sources are believed to be either quark stars or neutron stars, and a subclass of these are already observed by conventional means as pulsars or X-ray emitting celestial objects. Einstein@home is an official project of the Year of Physics. 2. climateprediction.net aims to investigate the approximations that have to be made in state-of-the-art climate models by running such models thousands of times under a range of approximations. This will help understand how sensitive different models are to small changes in, for example, the carbon dioxide and the sulphur cycle. This will contribute to exploring how climate may change in the next century under a wide range of different scenarios.
Criticality in Einstein-Gauss-Bonnet gravity: gravity without graviton
Energy Technology Data Exchange (ETDEWEB)
Fan, Zhong-Ying [Peking University, Center of High Energy Physics, Beijing (China); Chen, Bin [Peking University, Center of High Energy Physics, Beijing (China); Peking University, Department of Physics and State Key Laboratory of Nuclear Physics and Technology, Beijing (China); Collaborative Innovation Center of Quantum Matter, Beijing (China); Lue, Hong [Beijing Normal University, Department of Physics, Center for Advanced Quantum Studies, Beijing (China)
2016-10-15
General Einstein-Gauss-Bonnet gravity with a cosmological constant allows two (A)dS spacetimes as its vacuum solutions. We find a critical point in the parameter space where the two (A)dS spacetimes coalesce into one and the linearized perturbations lack any bilinear kinetic terms. The vacuum perturbations hence lose their interpretation as linear graviton modes at the critical point. Nevertheless, the critical theory admits black hole solutions due to the nonlinear effect. We also consider Einstein gravity extended with general quadratic curvature invariants and obtain critical points where the theory has no bilinear kinetic terms for either the scalar trace mode or the transverse modes. Such critical phenomena are expected to occur frequently in general higher-derivative gravities. (orig.)
Einstein contra Aristotle: the sound from the heavens
Neves, J C S
2016-01-01
In "On the Heavens" Aristotle criticizes the Pythagorean point of view which claims the existence of a cosmic music. According to the Pythagorean argument, there exists a cosmic music produced by stars and planets. These celestial bodies generate sound in its movements, and the music appears due to the cosmic harmony. For Aristotle, there is no sound produced by celestial bodies. Then, there is no music as well. However, recently, LIGO (Laser Interferometer Gravitational-Waves Observatory) has detected the gravitational waves predicted by Einstein. In some sense, a sound originated from black holes has been heard. That is, Einstein and LIGO appear to be with the Pythagoreanism and against the master of the Lyceum.
Jung, Tobias
In 1922, Franz Selety, university-bred philosopher and self-educated physicist and cosmologist, developed a molecular hierarchical, spatially infinite, Newtonian cosmological model. His considerations were based on his earlier philosophical work published in 1914 as well as on the early correspondence with Einstein in 1917. Historically, the roots of hierarchical models can be seen in 18th century investigations by Thomas Wright of Durham, Immanuel Kant and Johann Heinrich Lambert. Those investigations were taken up by Edmund Fournier d'Albe and Carl Charlier at the beginning of the 20th century. Selety's cosmological model was criticized by Einstein mainly due to its spatial infiniteness which in Einstein's opinion seemed to contradict Mach's principle. This criticism sheds light on Einstein's conviction that with his first cosmological model, namely the static, spatially infinite, though unbounded Einstein Universe of 1917, the appropriate cosmological theory already had been established.
Gutfreund, Hanoch
2017-01-01
First published in 1922 and based on lectures delivered in May 1921, Albert Einstein's The Meaning of Relativity offered an overview and explanation of the then new and controversial theory of relativity. The work would go on to become a monumental classic, printed in numerous editions and translations worldwide. Now, The Formative Years of Relativity introduces Einstein's masterpiece to new audiences. This beautiful volume contains Einstein's insightful text, accompanied by important historical materials and commentary looking at the origins and development of general relativity. Hanoch Gutfreund and Jurgen Renn provide fresh, original perspectives, placing Einstein's achievements into a broader context for all readers. In this book, Gutfreund and Renn tell the rich story behind the early reception, spread, and consequences of Einstein's ideas during the formative years of general relativity in the late 1910s and 1920s. They show that relativity's meaning changed radically throughout the nascent years of it...
Bose-Einstein correlations in WW pair production at LEP
Van Remortel, N
2003-01-01
This paper presents an overview of the latest results from the L3 and DELPHI collaborations concerning the measurement of Bose-Einstein correlations between identical bosons coming from different W's in fully hadronic WW decays. Using the same method, L3 sees no indication of any inter-W BEC effect, while DELPHI reports an indication of inter-W BEC between like-charged particles of the order of three standard deviations.
Casimir force on an interacting Bose-Einstein condensate
Energy Technology Data Exchange (ETDEWEB)
Biswas, Shyamal; Majumder, Dwipesh; Saha, Kush [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India); Bhattacharjee, J K [S.N. Bose National Centre for Basic Sciences, Sector 3, JD Block, Salt Lake, Kolkata 700098 (India); Chakravarty, Nabajit, E-mail: tpsb2@iacs.res.i [Positional Astronomy Centre, Block AQ, Plot 8, Sector 5, Salt Lake, Kolkata 700091 (India)
2010-04-28
We have presented an analytic theory for the Casimir force on a Bose-Einstein condensate which is confined between two parallel plates. We have considered Dirichlet boundary conditions for the condensate wavefunction as well as for the phonon field. We have shown that the condensate wavefunction (which obeys the Gross-Pitaevskii equation) is responsible for the mean field part of the Casimir force, which usually dominates over the quantum (fluctuations) part of the Casimir force.
Casimir force on interacting Bose-Einstein condensate
Biswas, Shyamal; Bhattacharjee, J K; Majumder, Dwipesh; Saha, Kush; Chakravarty, Nabajit
2009-01-01
We have presented an analytic theory for the Casimir force on a Bose-Einstein condensate (BEC) which is confined between two parallel plates. We have considered Dirichlet boundary conditions for the condensate wave function as well as for the phonon field. We have shown that, the condensate wave function (which obeys the Gross-Pitaevskii equation) is responsible for the mean field part of Casimir force, which usually dominates over the quantum (fluctuations) part of the Casimir force.
Spotlight on advances in VTE management: CALLISTO and EINSTEIN CHOICE.
Bach, Miriam; Bauersachs, Rupert
2016-09-28
Venous thromboembolism (VTE) is associated with numerous complications and high mortality rates. Patients with cancer are at high risk of developing cancer-associated thrombosis (CAT), and VTE recurrence is common. Evidence supporting use of non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) in patients with cancer is lacking - direct comparisons between NOACs and low-molecular-weight heparin (LMWH) are needed, along with patient-reported outcomes. Cancer Associated thrombosis - expLoring soLutions for patients through Treatment and Prevention with RivarOxaban (CALLISTO) is an international research programme exploring the potential of the direct, oral factor Xa inhibitor rivaroxaban for the prevention and treatment of CAT, supplementing existing data from EINSTEIN DVT and EINSTEIN PE. Here, we focus on four CALLISTO studies: A Study to Evaluate the Efficacy and Safety of Rivaroxaban Venous Thromboembolism Prophylaxis in Ambulatory Cancer Participants receiving Chemotherapy (CASSINI), Anticoagulation Therapy in SELECTeD Cancer Patients at Risk of Recurrence of Venous Thromboembolism (SELECT-D), Rivaroxaban in the Treatment of Venous Thromboembolism in Cancer Patients - a Randomized Phase III Study (CONKO-011) and a database analysis. Optimal anticoagulation duration for VTE treatment has always been unclear. Following favourable results for rivaroxaban 20 mg once-daily (Q. D.) for secondary VTE prevention (EINSTEIN EXT), EINSTEIN CHOICE is assessing rivaroxaban safety and (20 mg Q. D. or 10 mg Q. D.) vs acetylsalicylic acid (ASA), and will investigate whether an alternative rivaroxaban dose (10 mg Q. D.) could offer long-term VTE protection. It is anticipated that results from these studies will provide important answers and expand upon current evidence for rivaroxaban in VTE management.
Bose-Einstein condensation and indirect excitons: a review.
Combescot, Monique; Combescot, Roland; Dubin, François
2017-06-01
We review recent progress on Bose-Einstein condensation (BEC) of semiconductor excitons. The first part deals with theory, the second part with experiments. This Review is written at a time where the problem of exciton Bose-Einstein condensation has just been revived by the understanding that the exciton condensate must be dark because the exciton ground state is not coupled to light. Here, we theoretically discuss this missed understanding before providing its experimental support through experiments that scrutinize indirect excitons made of spatially separated electrons and holes. The theoretical part first discusses condensation of elementary bosons. In particular, the necessary inhibition of condensate fragmentation by exchange interaction is stressed, before extending the discussion to interacting bosons with spin degrees of freedom. The theoretical part then considers composite bosons made of two fermions like semiconductor excitons. The spin structure of the excitons is detailed, with emphasis on the crucial fact that ground-state excitons are dark: indeed, this imposes the exciton Bose-Einstein condensate to be not coupled to light in the dilute regime. Condensate fragmentations are then reconsidered. In particular, it is shown that while at low density, the exciton condensate is fully dark, it acquires a bright component, coherent with the dark one, beyond a density threshold: in this regime, the exciton condensate is 'gray'. The experimental part first discusses optical creation of indirect excitons in quantum wells, and the detection of their photoluminescence. Exciton thermalisation is also addressed, as well as available approaches to estimate the exciton density. We then switch to specific experiments where indirect excitons form a macroscopic fragmented ring. We show that such ring provides efficient electrostatic trapping in the region of the fragments where an essentially-dark exciton Bose-Einstein condensate is formed at sub-Kelvin bath
Bose-Einstein condensation of light: general theory.
Sob'yanin, Denis Nikolaevich
2013-08-01
A theory of Bose-Einstein condensation of light in a dye-filled optical microcavity is presented. The theory is based on the hierarchical maximum entropy principle and allows one to investigate the fluctuating behavior of the photon gas in the microcavity for all numbers of photons, dye molecules, and excitations at all temperatures, including the whole critical region. The master equation describing the interaction between photons and dye molecules in the microcavity is derived and the equivalence between the hierarchical maximum entropy principle and the master equation approach is shown. The cases of a fixed mean total photon number and a fixed total excitation number are considered, and a much sharper, nonparabolic onset of a macroscopic Bose-Einstein condensation of light in the latter case is demonstrated. The theory does not use the grand canonical approximation, takes into account the photon polarization degeneracy, and exactly describes the microscopic, mesoscopic, and macroscopic Bose-Einstein condensation of light. Under certain conditions, it predicts sub-Poissonian statistics of the photon condensate and the polarized photon condensate, and a universal relation takes place between the degrees of second-order coherence for these condensates. In the macroscopic case, there appear a sharp jump in the degrees of second-order coherence, a sharp jump and kink in the reduced standard deviations of the fluctuating numbers of photons in the polarized and whole condensates, and a sharp peak, a cusp, of the Mandel parameter for the whole condensate in the critical region. The possibility of nonclassical light generation in the microcavity with the photon Bose-Einstein condensate is predicted.
Brownian Motion, Fractal Structure and Verification of A. Einstein's Formula
Nikolić, Dragiša; Nešić, Ljubiša
2010-01-01
The work offers a simple experimental verification of A. Einstein and M. Smoluhovski's formula for Brownian motion. In this experiment we used latex solved in water, glycerin and alcohol while the observations and recording were done with a binocular optical microscope and a digital camera. Video material is recorded in separate files put on the Internet and can be downloaded and used for demonstration in class or further computer processing.
No open or flat bouncing cosmologies in Einstein gravity
Energy Technology Data Exchange (ETDEWEB)
Parikh, Maulik [Department of Physics and Beyond: Center for Fundamental Concepts in Science,Arizona State University,Tempe, AZ 85287 (United States)
2015-10-14
We show that, to first approximation, strings cannot propagate in bouncing open or flat Friedmann-Robertson-Walker universes. Specifically, the Virasoro constraint translates to the Ricci convergence condition in spacetime at leading order in the alpha-prime expansion. Thus one must go beyond minimally-coupled classical Einstein gravity in order to find bounce solutions that could be consistent with string theory. We map out some remaining possibilities for finding string-compatible cosmological bounces.
Derivation of Einstein-Cartan theory from general relativity
Petti, Richard J
2013-01-01
General relativity cannot describe exchange of intrinsic and orbital angular momentum. In 1922 E. Cartan proposed extending general relativity by including affine torsion, which resolves this problem. In 1986 the author published a derivation of Einstein Cartan theory from general relativity with classical spin, with no additional assumptions. This paper summarizes the derivation and adds simpler explanations of the derivation and correction of a factor of 2.
Through an understanding of thermoluminescence phenomena from Einstein radiation theory
Energy Technology Data Exchange (ETDEWEB)
Nieto H, B.; Vazquez C, G.A.; Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico)
2005-07-01
In this work we made an outline of Einstein's radiation theory and its connection with elementary TL theory. We did not pretend in this paper to discuss advanced TL theories in these terms. Our main goal was to explore the simplest relationships among radiation theory, such as, transition probabilities and mean time-lives with kinetic parameters of the Randall-Wilkins model. (Author)
Optical computing with soliton trains in Bose-Einstein condensates
Pinsker, Florian
2013-01-01
Optical computing devices can be implemented based on controlled generation of soliton trains in single and multicomponent Bose-Einstein condensates (BEC). Our concepts utilize the phenomenon that the frequency of soliton trains in BEC can be governed by changing interactions within the atom cloud. We use this property to store numbers in terms of those frequencies for a short time until observation. The properties of soliton trains can be changed in an intended way by other components of BEC...
Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time
Shapiro Key, Joey; Yunes, Nico; Grimberg, Irene
2015-01-01
Einstein's Symphony: A Gravitational Wave Voyage Through Space and Time is a gravitational wave astronomy planetarium show in production by a collaboration of scientists, filmmakers, and artisits from the Center for Gravitational Wave Astonomy (CGWA) at the University of Texas at Brownsville (UTB) and Montana State University (MSU). The project builds on the success of the interdisciplinary Celebrating Einstein collaboration. The artists and scientists who created the A Shout Across Time original film and the Black (W)hole immersive art installation for Celebrating Einstein are teaming with the Museum of the Rockies Taylor Planetarium staff and students to create a new full dome Digistar planetarium show that will be freely and widely distributed to planetaria in the US and abroad. The show uses images and animations filmed and collected for A Shout Across Time and for Black (W)hole as well as new images and animations and a new soundtrack composed and produced by the MSU School of Music to use the full capability of planetarium sound systems. The planetarium show will be narrated with ideas drawn from the Celebrating Einstein danced lecture on gravitational waves that the collaboration produced. The combination of products, resources, and team members assembled for this project allows us to create an original planetarium show for a fraction of the cost of a typical show. In addition, STEM education materials for G6-12 students and teachers will be provided to complement and support the show. This project is supported by the Texas Space Grant Consortium (TSGC), Montana Space Grant Consortium (MSGC), and the American Physical Society (APS).
Local and Global Existence Theorems for the Einstein Equations
Directory of Open Access Journals (Sweden)
Alan D. Rendall
1998-01-01
Full Text Available This article is a guide to the literature on existence theorems for the Einstein equations which also draws attention to open problems in the field. The local in time Cauchy problem, which is relatively well understood, is treated first. Next global results for solutionswith symmetry are discussed. This is followed by a presentation of global results in the case of small data, and some miscellaneous topics connected with the main theme.
Images of Empty Space: Einstein’s Word Pictures
1988-08-10
34L FILE Co-y CV N m The Artificial Intelligence and Psychology Project Departments of’ Computer Science and Psychologv Carn w.gi M l lhon h miersilh...EINSTEIN’S WORD PICTURES Technical Report AlP - 90 Herbert A. Simon Depflmnt of Psychology Canegie Meon Univey Plttsburgh, PA 15213 10 August 1988 This... perintted for any purpose of the United States Goverment. Approved for public release; distributlon unlimited. DTICS ELECTE B D UnclassifiLed REPORT
On relativistic particle creation in Bose-Einstein condensates
Sabín, Carlos; Fuentes, Ivette
2014-01-01
We show that particle creation of Bogoliubov modes in a Bose-Einstein condensate due to the accelerated motion of the trap is a genuinely relativistic effect. To this end we show that Bogoliubov modes can be described by a time rescaling of the Minkowski metric. A consequence of this is that Rindler transformations are perceived by the phonons as generalised Rindler transformations where the speed of light is replaced by the speed of sound, enhancing particle creation at small velocities. Sin...
Sonic black holes in dilute Bose-Einstein condensates
Garay, L. J.; Anglin, J. R.; Cirac, J. I.; Zoller, P.
2000-01-01
The sonic analog of a gravitational black hole in dilute-gas Bose-Einstein condensates is investigated. It is shown that there exist both dynamically stable and unstable configurations which, in the hydrodynamic limit, exhibit behaviors completely analogous to that of gravitational black holes. The dynamical instabilities involve the creation of quasiparticle pairs in positive and negative energy states. We illustrate these features in two qualitatively different one-dimensional models, namel...
Quantum Depletion of a Homogeneous Bose-Einstein Condensate
Lopes, Raphael; Eigen, Christoph; Navon, Nir; Clément, David; Smith, Robert P.; Hadzibabic, Zoran
2017-11-01
We measure the quantum depletion of an interacting homogeneous Bose-Einstein condensate and confirm the 70-year-old theory of Bogoliubov. The observed condensate depletion is reversibly tunable by changing the strength of the interparticle interactions. Our atomic homogeneous condensate is produced in an optical-box trap, the interactions are tuned via a magnetic Feshbach resonance, and the condensed fraction is determined by momentum-selective two-photon Bragg scattering.
Holographic superconductors in Einstein-æther gravity
Lin, Kai; Wu, Yumei
2017-11-01
In this paper, we apply Anti-de Sitter (AdS) black hole solution of the Einstein-æther theory to the study of the holographic superconductor and show that the AdS black hole solution can be rewritten in some very simple forms, from which it is easy to identify the locations of various killing horizons. Then, we investigate the different effects of these horizons on the holographic superconductor.
Nonstatic plane-symmetric solutions for Einstein-Maxwell equations
Energy Technology Data Exchange (ETDEWEB)
Hajj-Boutros, J.; Sfeila, J.
1985-11-16
The general solution of the Einstein-Maxwell field equations is obtained under the assumptions that 1) the source of the gravitational field is a charged dust, 2) the space-time is plane-symmetric, 3) the metric is of the form ds/sup 2/ = dt/sup 2/ - exp (2u(t, z)) dz/sup 2/ - Z/sup 2/(z) T/sup 2/(t)(dx/sup 2/ + dy/sup 2/). (orig.).
Critical remarks on Bruno Thuring's polemic against Einstein.
Kerschbaum, F.; Lackner, K.; Posch, T.
2005-08-01
Bruno Thüring (1905-1989) was among those scientists who joined the campaign against Einstein's Theories of Relativity which was undertaken in the name of so-called "German Physics". Thüring served as director of Vienna's University Observatory between 1940-45; hence, we present biographical information on his scientific and administrative activities in Vienna, partly based on interviews with time-witnesses. It is one of Thüring's basic convictions that Einstein's work cannot be understood without an analysis of the developments of physics and philosophy in the 19th century. While this is true generally, Thüring's account of these developments is rather superficial. For example, Thüring considers Kant's idea of the a priori status of geometry as a wholly sufficient epistemological foundation of mechanics, while both post-Kantian idealism and positivism were a mere backdrop to the development of knowledge - a view which can hardly stand critical examination. Concerning the impact of Einstein's theories on physics, Thüring argues that the principles of special and general relativity be nothing else but arbitrary decisions (as opposed to real insights). Hence these principles would never be verified or falsified by any experiment. The Michelson-Moreley experiment, e.g., would not prove the principles of special relativity. Thüring considers Einstein's interpretation of this experiment as premature and as an arbitrary judgement on a very particular and subaltern phenomenon which would not justify the conclusion that the velocity of the Earth with respect to the luminiferous aether be immeasurable by just any experimental technique.
Beyond Einstein: A live webcast from around the Globe
Communication Team
2005-01-01
The longest-ever organised webcast: once round the clock and all the way round the world! Twelve hours of online broadcast, a worldwide web of speakers from locations such as the Imperial College in London, Fermilab in Chicago and the Exploratorium in San Francisco. The result: a global discussion of the grand themes of Einstein's physics, such as relativity, gravitational waves, mass and gravity, antimatter and the origins of the Big Bang.
Bose–Einstein condensation in the Rindler space
Directory of Open Access Journals (Sweden)
Shingo Takeuchi
2015-11-01
Full Text Available Based on the Unruh effect, we calculate the critical acceleration of the Bose–Einstein condensation in a free complex scalar field at finite density in the Rindler space. Our model corresponds to an ideal gas performing constantly accelerating motion in a Minkowski space–time at zero-temperature, where the gas is composed of the complex scalar particles and it can be thought to be in a thermal-bath with the Unruh temperature. In the accelerating frame, the model will be in the Bose–Einstein condensation state at low acceleration; on the other hand, there will be no condensation at high acceleration by the thermal excitation brought into by the Unruh effect. Our critical acceleration is the one at which the Bose–Einstein condensation begins to appear in the accelerating frame when we decrease the acceleration gradually. To carry out the calculation, we assume that the critical acceleration is much larger than the mass of the particle.
Implications of Einstein-Weyl Causality on Quantum Mechanics
Bendaniel, David
A fundamental physical principle that has consequences for the topology of space-time is the principle of Einstein-Weyl causality. This also has quantum mechanical manifestations. Borchers and Sen have rigorously investigated the mathematical implications of Einstein-Weyl causality and shown the denumerable space-time Q2 would be implied. They were left with important philosophical paradoxes regarding the nature of the physical real line E, e.g., whether E = R, the real line of mathematics. In order to remove these paradoxes an investigation into a constructible foundation is suggested. We have pursued such a program and find it indeed provides a dense, denumerable space-time and, moreover, an interesting connection with quantum mechanics. We first show that this constructible theory contains polynomial functions which are locally homeomorphic with a dense, denumerable metric space R* and are inherently quantized. Eigenfunctions governing fields can then be effectively obtained by computational iteration. Postulating a Lagrangian for fields in a compactified space-time, we get a general description of which the Schrodinger equation is a special case. From these results we can then also show that this denumerable space-time is relational (in the sense that space is not infinitesimally small if and only if it contains a quantized field) and, since Q2 is imbedded in R*2, it directly fulfills the strict topological requirements for Einstein-Weyl causality. Therefore, the theory predicts that E = R*.
Characterizing SL2S galaxy groups using the Einstein radius
DEFF Research Database (Denmark)
Verdugo, T.; Motta, V.; Foex, G.
2014-01-01
Aims. We aim to study the reliability of RA (the distance from the arcs to the center of the lens) as a measure of the Einstein radius in galaxy groups. In addition, we want to analyze the possibility of using RA as a proxy to characterize some properties of galaxy groups, such as luminosity (L......) and richness (N). Methods. We analyzed the Einstein radius, θE, in our sample of Strong Lensing Legacy Survey (SL2S) galaxy groups, and compared it with RA, using three different approaches: 1) the velocity dispersion obtained from weak lensing assuming a singular isothermal sphere profile (θE,I); 2) a strong.......7 ± 0.2)RA, θE,II = (0.4 ± 1.5) + (1.1 ± 0.4)RA, and θE,III = (0.4 ± 1.5) + (0.9 ± 0.3)RA for each method respectively. We found weak evidence of anti-correlation between RA and z, with Log RA = (0.58 ± 0.06) − (0.04 ± 0.1)z, suggesting a possible evolution of the Einstein radius with z, as reported...
The Einstein-Brazil Fogarty: A decade of synergy.
Nosanchuk, Joshua D; Nosanchuk, Murphy D; Rodrigues, Marcio L; Nimrichter, Leonardo; Carvalho, Antonio C Campos de; Weiss, Louis M; Spray, David C; Tanowitz, Herbert B
2015-01-01
A rich, collaborative program funded by the US NIH Fogarty program in 2004 has provided for a decade of remarkable opportunities for scientific advancement through the training of Brazilian undergraduate, graduate and postdoctoral students from the Federal University and Oswaldo Cruz Foundation systems at Albert Einstein College of Medicine. The focus of the program has been on the development of trainees in the broad field of Infectious Diseases, with a particular focus on diseases of importance to the Brazilian population. Talented trainees from various regions in Brazil came to Einstein to learn techniques and study fungal, parasitic and bacterial pathogens. In total, 43 trainees enthusiastically participated in the program. In addition to laboratory work, these students took a variety of courses at Einstein, presented their results at local, national and international meetings, and productively published their findings. This program has led to a remarkable synergy of scientific discovery for the participants during a time of rapid acceleration of the scientific growth in Brazil. This collaboration between Brazilian and US scientists has benefitted both countries and serves as a model for future training programs between these countries.
The Media of Relativity: Einstein and Telecommunications Technologies.
Canales, Jimena
2015-07-01
How are fundamental constants, such as "c" for the speed of light, related to the technological environments that produce them? Relativistic cosmology, developed first by Albert Einstein, depended on military and commercial innovations in telecommunications. Prominent physicists (Hans Reichenbach, Max Born, Paul Langevin, Louis de Broglie, and Léon Brillouin, among others) worked in radio units during WWI and incorporated battlefield lessons into their research. Relativity physicists, working at the intersection of physics and optics by investigating light and electricity, responded to new challenges by developing a novel scientific framework. Ideas about lengths and solid bodies were overhauled because the old Newtonian mechanics assumed the possibility of "instantaneous signaling at a distance." Einstein's universe, where time and space dilated, where the shortest path between two points was often curved and non-Euclidean, followed the rules of electromagnetic "signal" transmission. For these scientists, light's constant speed in the absence of a gravitational field-a fundamental tenet of Einstein's theory-was a lesson derived from communication technologies.
Focus: the elusive icon: Einstein, 1905-2005. Introduction.
Galison, Peter
2004-12-01
As Einstein's portrait comes increasingly to resemble an icon, we lose more than detail--his writings and actions lose all reference. This is as true for his physics as it is for his philosophy and his politics; the best of recent work aims to remove Einstein's interventions from the abstract sphere of Delphic pronouncements and to insert them in the stream of real events, real arguments. Politically, this means attending to McCarthyism, Paul Robeson, the Arab-Israeli conflict. Philosophically, it means tying his concerns, for example, to late nineteenth-century neo-Kantian debates and to his own struggles inside science. And where physics is concerned, it means attending both in the narrow to his responses to others' work and his reactions to his own sometimes misfired early work on, for example, general relativity and to the wider context of technological developments. Einstein remains and will remain a magnet for historians, philosophers, and scientists; the essays assembled here represent a strong sampling--but only a sampling--of a fascinating new generation of work on this perennial figure.
Bose–Einstein graviton condensate in a Schwarzschild black hole
Alfaro, Jorge; Espriu, Domènec; Gabbanelli, Luciano
2018-01-01
We analyze in detail a previous proposal by Dvali and Gómez that black holes could be treated as consisting of a Bose–Einstein condensate of gravitons. In order to do so we extend the Einstein–Hilbert action with a chemical potential-like term, thus placing ourselves in a grand-canonical ensemble. The form and characteristics of this chemical potential-like piece are discussed in some detail. We argue that the resulting equations of motion derived from the action could be interpreted as the Gross–Pitaevskii equation describing a graviton Bose–Einstein condensate trapped by the black hole gravitational field. After this, we proceed to expand the ensuring equations of motion up to second order around the classical Schwarzschild metric so that some non-linear terms in the metric fluctuation are kept. Next we search for solutions and, modulo some very plausible assumptions, we find out that the condensate vanishes outside the horizon but is non-zero in its interior. Inspired by a linearized approximation around the horizon we are able to find an exact solution for the mean-field wave function describing the graviton Bose–Einstein condensate in the black hole interior. After this, we can rederive some of the relations involving the number of gravitons N and the black hole characteristics along the lines suggested by Dvali and Gómez.
G. Einstein matrix and nano-biophotonic treatment
Przybyl-Einstein, George; Moratin, Holdy; Garcia, Eduardo
2005-04-01
The publication is presenting the Einstein Matrix Treatment Method and initial results for blood borne diseases on example of hepatitis, HIV and arthritis. The initial research was conducted at Einstein Clinical Laboratories S.A. on limited funds. The treatment and method is strongly recommended for specific viruses bacteria in blood borne diseases but also for treatment of none specific viruses and bacteria in emergency treatments as SARS or ANTHRAX to safe life of the human. In the past years the Individual's Safety is in jeopardy by natural viral infections as well as by engineering cultured viruses and bacteria. Viruses mutate and become more resistant to current known medical treatment, in many cases partially efficient. This event required new testing method to investigate the possibility of treatments and to create new vaccine for non-specific viral and bacteria or viruses infections that causes death to thousands adults and children. The authors present in this paper the possibility of treatment of the non-specific viral, bacterial infections of the blood in human body. This treatment has safe procedure and no known side effect up to this time for patients that were treated at Einstein Clinical Laboratories SA.
Ambitwistor formulations of R 2 gravity and ( DF)2 gauge theories
Azevedo, Thales; Engelund, Oluf Tang
2017-11-01
We consider D-dimensional amplitudes in R 2 gravities (conformal gravity in D = 4) and in the recently introduced ( DF)2 gauge theory, from the perspective of the CHY formulae and ambitwistor string theory. These theories are related through the BCJ double-copy construction, and the ( DF)2 gauge theory obeys color-kinematics duality. We work out the worldsheet details of these theories and show that they admit a formulation as integrals on the support of the scattering equations, or alternatively, as ambitwistor string theories. For gravity, this generalizes the work done by Berkovits and Witten on conformal gravity to D dimensions. The ambitwistor is also interpreted as a D-dimensional generalization of Witten's twistor string (SYM + conformal supergravity). As part of our ambitwistor investigation, we discover another ( DF)2 gauge theory containing a photon that couples to Einstein gravity. This theory can provide an alternative KLT description of Einstein gravity compared to the usual Yang-Mills squared.
A Note on the Relationship Between Solutions of Einstein, Ramanujan and Chazy Equations
Esmakhanova, Kuralay; Myrzakulov, Yerlan; Nugmanova, Gulgasyl; Myrzakulov, Ratbay
2012-04-01
The Einstein equation for the Friedmann-Robertson-Walker metric plays a fundamental role in cosmology. The direct search of the exact solutions of the Einstein equation even in this simple metric case is sometime a hard job. Therefore, it is useful to construct solutions of the Einstein equation using a known solutions of some other equations which are equivalent or related to the Einstein equation. In this work, we establish the relationship the Einstein equation with two other famous equations namely the Ramanujan equation and the Chazy equation. Both these two equations play an important role in the number theory. Using the known solutions of the Ramanujan and Chazy equations, we find the corresponding solutions of the Einstein equation.
Static trace free Einstein equations and stellar distributions
Hansraj, Sudan; Goswami, Rituparno; Mkhize, Njabulo; Ellis, George
2017-08-01
We construct models of static spherical distributions of the perfect fluid in trace free Einstein gravity theory. The equations governing the gravitational field are equivalent to standard Einstein's equations; however, their presentation is manifestly different, which motivates the question whether new information would emerge due to the nonlinearity of the field equations. The incompressible fluid assumption does not lead to the well known Schwarzschild interior metric of Einstein gravity, and a term denoting the presence of a cosmological constant is present on account of the integration process. The Schwarzschild interior is regained as a special case of a richer geometry. On the other hand, when the Schwarzschild geometry is prescribed, a constant density fluid emerges consistent with the standard equations. A complete model of an isothermal fluid sphere with pressure and density obeying the inverse square law is obtained. Corrections to the model previously presented in the literature by Saslaw et al. are exhibited. The isothermal ansatz does not yield a constant gravitational potential in general, but both potentials are position dependent. Conversely, it is shown that assuming a constant gr r gravitational potential does not yield an isothermal fluid in general as is the case in standard general relativity. The results of the standard Einstein equations are special cases of the models reported here. Noteworthy is the fact that whereas the previously reported isothermal solution was only of cosmological interest, the solution reported herein admits compact objects by virtue of the fact that a pressure free hypersurface exists. Finally we analyze the consequences of selecting the Finch-Skea metric as the seed solution. The density profiles match; however, there is a deviation between the pressure profiles with the Einstein case although the qualitative behavior is the same. It is shown in detail that the model satisfies elementary requirements for physical
Liposomal paclitaxel formulations.
Koudelka, Stěpán; Turánek, Jaroslav
2012-11-10
Over the past three decades, taxanes represent one of the most important new classes of drugs approved in oncology. Paclitaxel (PTX), the prototype of this class, is an anti-cancer drug approved for the treatment of breast and ovarian cancer. However, notwithstanding a suitable premedication, present-day chemotherapy employing a commercial preparation of PTX (Taxol®) is associated with serious side effects and hypersensitivity reactions. Liposomes represent advanced and versatile delivery systems for drugs. Generally, both in vivo mice tumor models and human clinical trials demonstrated that liposomal PTX formulations significantly increase a maximum tolerated dose (MTD) of PTX which outperform that for Taxol®. Liposomal PTX formulations are in various stages of clinical trials. LEP-ETU (NeoPharm) and EndoTAG®-1 (Medigene) have reached the phase II of the clinical trials; Lipusu® (Luye Pharma Group) has already been commercialized. Present achievements in the preparation of various liposomal formulations of PTX, the development of targeted liposomal PTX systems and the progress in clinical testing of liposomal PTX are discussed in this review summarizing about 30 years of liposomal PTX development. Copyright © 2012 Elsevier B.V. All rights reserved.
Renormalization of Einstein gravity through a derivative-dependent field redefinition
Slovick, Brian
2018-01-01
This work explores an alternative solution to the problem of renormalizability in Einstein gravity. In the proposed approach, Einstein gravity is transformed into the renormalizable theory of four-derivative gravity by applying a local field redefinition containing an infinite number of higher derivatives. It is also shown that the current-current amplitude is invariant with the field redefinition, and thus the unitarity of Einstein gravity is preserved.
Einstein on Race and Racism, presented by Fred Jerome and Rodger Taylor
Jerome, Fred; Taylor, Rodger
2007-10-01
It is little-known that physicist Albert Einstein strongly held the view that ``Racism is America's worst disease.'' Einstein was active in the fight against racism from the 1930's until his death in 1955. Included among his friends were a number of important Afro-American figures, including the educator W.E.B. DuBois, the actor and basso profundo singer Paul Robeson, and the soprano Marian Anderson. Based on the authors' work ``Einstein on Race and Racism.''
BOOK REVIEW: Einstein's Jury: The Race to Test Relativity
Ehlers, Jürgen
2007-10-01
'I know very well that my theory rests on a shaky foundation. What attracts me to it is that it leads to consequences that seem to be accessible to experiment, and it provides a starting point for the theoretical understanding of gravitation', wrote Einstein in 1911. Einstein's Jury by Jeffrey Crelinsten—well documented, well written, and fascinating to read—describes how, from 1909 on, Einstein's two theories of relativity became known to astronomers, and how the predictions made between 1907 and 1915 were received as challenges to observers. The author gives a non-technical account of the efforts made until 1930 to test these predictions; he focuses on two of the three classical tests, namely gravitational redshift and bending of light; the 'jury' consists mainly of American observers—Adams, Campbell, Curtis, Hale, Perrin, St John, Trumpler and others—working with newly built large telescopes, and the Britons Eddington and Evershed. The major steps which, after a long struggle, convinced the majority of astronomers that Einstein was right, are narrated chronologically in rather great detail, especially the work at Lick Observatory, before and after the famous British observation of 1919, on solar eclipses, and the work at Mount Wilson and the Indian Kodaikanal Observatories to extract the gravitational redshift from the complicated spectrum of the sun. The account of the eclipse work which was carried out between 1918 and 1923 by Lick astronomers corrects the impression suggested by many historical accounts that the British expedition alone settled the light-bending question. Apart from these main topics, the anomalous perihelion advance of Mercury and the ether problem are covered. By concentrating on astronomy rather than on physics this book complements the rich but repetitive literature on Einstein and relativity which appeared in connection with the commemoration of Einstein's annus mirabilis, 2005. The well told stories include curiosities such as
Kamerlingh Onnes en Einstein: ‘Uw hulp zal dus veel goeds tot stand kunnen brengen’
Directory of Open Access Journals (Sweden)
Dirk van Delft
2016-10-01
Full Text Available Kamerlingh Onnes and EinsteinIn 1901 Albert Einstein unsuccessfully applied for the post of assistant in Heike Kamerlingh Onnes’ cryogenics laboratory. Ten years later the two scientists finally met each other. Einstein was interested in the experimental research taking place in Leiden into critical light scattering, a field to which he had made theoretical contributions himself. Kamerlingh Onnes on his part hoped Einstein might throw light on the unexplained phenomenon of superconductivity and on the influence of quantum effects on Leiden’s key research topic: equation of state.
The legacy of Albert Einstein a collection of essays in celebration of the Year of Physics
2007-01-01
This indispensable volume contains a compendium of articles covering a vast range of topics in physics which were begun or influenced by the works of Albert Einstein: special relativity, quantum theory, statistical physics, condensed matter physics, general relativity, geometry, cosmology and unified field theory. An essay on the societal role of Einstein is included. These articles, written by some of the renowned experts, offer an insider's view of the exciting world of fundamental science. Sample Chapter(s). Chapter 1: Einstein and the Search for Unification (625 KB). Contents: Einstein and
Weinstein, Galina
2013-01-01
In 1956/1970 Gamow wrote that much later, when he was discussing cosmological problems with Einstein, he remarked that the introduction of the cosmological term was the "biggest blunder" he ever made in his life. But the cosmological constant rears its ugly head again and again and again. Apparently, Einstein himself has never used the apercu "biggest blunder"; nevertheless a vast literature grew up around this notion and associated it with Einstein. The present work is prompted by questions put by Mario Livio in his latest book "Brilliant Blunders" as to the phrase "biggest blunder": Did Einstein actually say, "biggest blunder"? I show that in 1947 Einstein wrote Lemaitre that he found it "very ugly" that the field law of gravitation should be composed of two logically independent terms. Earlier, in 1922 Einstein wrote Max Born that he committed "a monumental blunder some time ago". In 1965 Born commented: "Here Einstein admits that the considerations which led him to the positive-ray experiments were wrong:...
Self-Gravitating Bose-Einstein Condensates and the Thomas-Fermi Approximation
Directory of Open Access Journals (Sweden)
Viktor T. Toth
2016-08-01
Full Text Available Self-gravitating Bose-Einstein condensates (BEC have been proposed in various astrophysical contexts, including Bose-stars and BEC dark matter halos. These systems are described by a combination of the Gross-Pitaevskii and Poisson equations (the GPP system. In the analysis of these hypothetical objects, the Thomas-Fermi (TF approximation is widely used. This approximation is based on the assumption that in the presence of a large number of particles, the kinetic term in the Gross-Pitaevskii energy functional can be neglected, yet it is well known that this assumption is violated near the condensate surface. We also show that the total energy of the self-gravitating condensate in the TF-approximation is positive. The stability of a self-gravitating system is dependent on the total energy being negative. Therefore, the TF-approximation is ill suited to formulate initial conditions in numerical simulations. As an alternative, we offer an approximate solution of the full GPP system.
Engineering bright solitons to enhance the stability of two-component Bose–Einstein condensates
Energy Technology Data Exchange (ETDEWEB)
Radha, R., E-mail: radha_ramaswamy@yahoo.com [Centre for Nonlinear Science, PG and Research Dept. of Physics, Govt. College for Women (Autonomous), Kumbakonam 612001 (India); Vinayagam, P.S.; Sudharsan, J.B. [Centre for Nonlinear Science, PG and Research Dept. of Physics, Govt. College for Women (Autonomous), Kumbakonam 612001 (India); Liu, Wu-Ming, E-mail: wmliu@iphy.ac.cn [Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing-100190 (China); Malomed, Boris A., E-mail: malomed@post.tau.ac.il [Department of Physical Electronics, School of Electrical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978 (Israel)
2015-12-04
We consider a system of coupled Gross–Pitaevskii (GP) equations describing a binary quasi-one-dimensional Bose–Einstein condensate (BEC) with intrinsic time-dependent attractive interactions, placed in a time-dependent expulsive parabolic potential, in a special case when the system is integrable (a deformed Manakov's system). Since the nonlinearity in the integrable system which represents binary attractive interactions exponentially decays with time, solitons are also subject to decay. Nevertheless, it is shown that the robustness of bright solitons can be enhanced in this system, making their respective lifetime longer, by matching the time dependence of the interaction strength (adjusted with the help of the Feshbach-resonance management) to the time modulation of the strength of the parabolic potential. The analytical results, and their stability, are corroborated by numerical simulations. In particular, we demonstrate that the addition of random noise does not impact the stability of the solitons. - Highlights: • We formulate a versatile mechanism to enhance the lifetime of vectorial condensates employing Feshbach Resonance. • Vectorial condensates in a transient harmonic trap are more long lived compared to their counterpart in a time independent harmonic trap. • Corroborate the exact analytical results with numerical simulations. • Addition of random noise does not impact the stability of vector BECs.
Heavily-doped 2D-quantized structures and the Einstein relation
Ghatak, Kamakhya P
2015-01-01
This book presents the Einstein Relation(ER) in two-dimensional (2-D) Heavily Doped(HD) Quantized Structures. The materials considered are quantized structures of HD non-linear optical, III-V, II-VI, Ge, Te, Platinum Antimonide, stressed materials, GaP, Gallium Antimonide, II-V, Bismuth Telluride together with various types of HD superlattices and their Quantized counterparts respectively. The ER in HD opto-electronic materials and their nanostructures is studied in the presence of strong light waves and intense electric fields on the basis of newly formulated electron dispersion laws that control the studies of such quantum effect devices. The suggestion for the experimental determination of HD 2D and 3D ERs and the importance of measurement of band gap in HD optoelectronic materials under intense built-in electric field in nanodevices and strong external photo excitation (for measuring photon induced physical properties) are also discussed in this context. The influence of crossed electric and quantizing ma...
Gheorghiu, Tamara; Ruchin, Vyacheslav; Vacaru, Olivia; Vacaru, Sergiu I.
2016-06-01
We study geometric relativistic flow and Ricci soliton equations which (for respective nonholonomic constraints and self-similarity conditions) are equivalent to the gravitational field equations of R2 gravity and/or to the Einstein equations with scalar field in general relativity, GR. Perelman's functionals are generalized for modified gravity theories, MGTs, which allows to formulate an analogous statistical thermodynamics for geometric flows and Ricci solitons. There are constructed and analyzed generic off-diagonal black ellipsoid, black hole and solitonic exact solutions in MGTs and GR encoding geometric flow evolution scenarios and nonlinear parametric interactions. Such new classes of solutions in MGTs can be with polarized and/or running constants, nonholonomically deformed horizons and/or embedded self-consistently into solitonic backgrounds. They exist also in GR as generic off-diagonal vacuum configurations with effective cosmological constant and/or mimicking effective scalar field interactions. Finally, we compute Perelman's energy and entropy for black ellipsoids and evolution solitons in R2 gravity.
L'essenza fenomenologica della relatività. Questioni di confine tra Husserl e Einstein
Directory of Open Access Journals (Sweden)
Giorgio Jules Mastrobisi
2016-06-01
Full Text Available THE PHENOMENOLOGICAL ESSENCE OF RELATIVITY. MATTERS CONCERNING THE BORDER BETWEEN HUSSERL AND EINSTEIN According to Hermann Weyl, Einstein’s Relativity Theory is a method that combines “analysis of essence” and “mathematical construction”. From this point of view, in this article I try to establish a parallelism between the formulation of Einstein’s Theory of Relativity and Husserl’s Phenomenology based on the comparison of the original texts and manuscripts. From this analysis, e.g. the conception of the gravitational field, as important result of the General Relativity Theory, seems to be nothing else but a new type of “essence”, a phenomenological essence, in an environing objective world that is the “world‐of‐life”. In this world, pre‐ scientific world of the everyday life experience, the reality is given us as a relativistic reality dependent on the subjective activity of the individual knowers. On the basis of the consciousness data, we reconstruct the real and objective world of experience as starting point for every mathematical and physical construction of the world comprehension. This study seeks to present a convincing case both that Husserlian phenomenology influenced 20th Century natural science in an important way.
Conserved charges of black holes in Weyl and Einstein-Gauss-Bonnet gravities
Energy Technology Data Exchange (ETDEWEB)
Peng, Jun-Jin [SEEE, Wuhan Textile University, Institute of Technical Physics, Wuhan, Hubei (China); Chinese Academy of Sciences, Kavli Institute for Theoretical Physics China, Institute of Theoretical Physics, P.O. Box 2735, Beijing (China)
2014-11-15
An off-shell generalization of the Abbott-Deser-Tekin (ADT) conserved charge was recently proposed by Kim et al. They achieved this by introducing off-shell Noether currents and potentials. In this paper, we construct the crucial off-shell Noether current by the variation of the Bianchi identity for the expression of EOM, with the help of the property of Killing vector. Our Noether current, which contains an additional term that is just one half of the Lie derivative of a surface term with respect to the Killing vector, takes a different form in comparison with the one in their work. Then we employ the generalized formulation to calculate the quasi-local conserved charges for the most general charged spherically symmetric and the dyonic rotating black holes with AdS asymptotics in four-dimensional conformal Weyl gravity, as well as the charged spherically symmetric black holes in arbitrary dimensional Einstein-Gauss-Bonnet gravity coupled to Maxwell or nonlinear electrodynamics in AdS spacetime. Our results confirm those obtained through other methods in the literature. (orig.)
Systematic Equation Formulation
DEFF Research Database (Denmark)
Lindberg, Erik
2007-01-01
A tutorial giving a very simple introduction to the set-up of the equations used as a model for an electrical/electronic circuit. The aim is to find a method which is as simple and general as possible with respect to implementation in a computer program. The “Modified Nodal Approach”, MNA, and th......, and the “Controlled Source Approach”, CSA, for systematic equation formulation are investigated. It is suggested that the kernel of the P Spice program based on MNA is reprogrammed....
,
2016-01-01
With Einstein's inertial motion (free-falling and non-rotating relative to gyroscopes), geodesics for non-relativistic particles can intersect repeatedly, allowing one to compute the space-time curvature $R^{\\hat{0} \\hat{0}}$ exactly. Einstein's $R^{\\hat{0} \\hat{0}}$ for strong gravitational fields and for relativistic source-matter is identical with the Newtonian expression for the relative radial acceleration of neighboring free-falling test-particles, spherically averaged.--- Einstein's field equations follow from Newtonian experiments, local Lorentz-covariance, and energy-momentum conservation combined with the Bianchi identity.
Ether formulations of relativity
Energy Technology Data Exchange (ETDEWEB)
Duffy, M.C.
1980-12-01
Contemporary ether theories are surveyed and criticized, especially those formally identical to orthodox Relativity. The historical development of Relativity, Special and General, in terms of an ether, is briefly indicated. Classical interpretations of Generalized Relativity using ether are compared to Euclidean formulations using a background space. The history of a sub-group of theories, formulating a 'new' Relativity involving modified transforms, is outlined. According to the theory with which they agree, recent supposed detections of drift are classified and criticized. Cosmological evidence suggesting an ether is mentioned. Only ether theories formally identical to Relativity have been published in depth. They stand criticized as being contrary to the positivist spirit. The history of mechanical analogues is traced, from Hartley's representing gravitating matter as spherical standing waves, to recent suggestions that vortex-sponge might model electromagnetic, quantum, uncertainty and faster-than-light phenomena. Contemporary theories are particular physical theories, themselves 'second interpretations' of a primary mathematical model. Mechanical analogues are auxiliary, not necessary, to other theory, disclosing relationships between classical and non-classical descriptions of assemblies charging state. The ether-relativity polemic, part of a broader dispute about relativity, is founded on mistaken conceptions of the roles of mathematical and physical models, mechanical analogues; and a distored view of history, which indicates that ether theories have become relativistic. 103 references.
Testing Brans-Dicke gravity using the Einstein telescope
Zhang, Xing; Yu, Jiming; Liu, Tan; Zhao, Wen; Wang, Anzhong
2017-06-01
Gravitational radiation is an excellent field for testing theories of gravity in strong gravitational fields. The current observations on the gravitational-wave (GW) bursts by LIGO have already placed various constraints on the alternative theories of gravity. In this paper, we investigate the possible bounds which could be placed on the Brans-Dicke gravity using GW detection from inspiraling compact binaries with the proposed Einstein Telescope, a third-generation GW detector. We first calculate in detail the waveforms of gravitational radiation in the lowest post-Newtonian approximation, including the tensor and scalar fields, which can be divided into the three polarization modes, i.e., "plus mode," "cross mode," and "breathing mode." Applying the stationary phase approximation, we obtain their Fourier transforms, and derive the correction terms in amplitude, phase, and polarization of GWs, relative to the corresponding results in general relativity. Imposing the noise level of the Einstein Telescope, we find that the GW detection from inspiraling compact binaries, composed of a neutron star and a black hole, can place stringent constraints on the Brans-Dicke gravity. The bound on the coupling constant ωBD depends on the mass, sky position, inclination angle, polarization angle, luminosity distance, redshift distribution, and total observed number NGW of the binary systems. Taking into account all the burst events up to redshift z =5 , we find that the bound could be ωBD≳1 06×(NGW/1 04)1/2. Even for the conservative estimation with 1 04 observed events, the bound is still more than one order tighter than the current limit from Solar System experiments. So, we conclude that the Einstein Telescope will provide a powerful platform to test alternative theories of gravity.
Einstein-Gauss-Bonnet black strings at large D
Chen, Bin; Li, Peng-Cheng; Zhang, Cheng-Yong
2017-10-01
We study the black string solutions in the Einstein-Gauss-Bonnet(EGB) theory at large D. By using the 1/ D expansion in the near horizon region we derive the effective equations that describe the dynamics of the EGB black strings. The uniform and non-uniform black strings are obtained as the static solutions of the effective equations. From the perturbation analysis of the effective equations, we find that thin EGB black strings suffer from the Gregory-Laflamme instablity and the GB term weakens the instability when the GB coefficient is small, however, when the GB coefficient is large the GB term enhances the instability. Furthermore, we numerically solve the effective equations to study the non-linear instability. It turns out that the thin black strings are unstable to developing inhomogeneities along their length, and at late times they asymptote to the stable non-uniform black strings. The behavior is qualitatively similar to the case in the Einstein gravity. Compared with the black string instability in the Einstein gravity at large D, when the GB coefficient is small the time needed to reach to final state increases, but when the GB coefficient is large the time to reach to final state decreases. Starting from the point of view in which the effective equations can be interpreted as the equations for the dynamical fluid, we evaluate the transport coefficients and find that the ratio of the shear viscosity and the entropy density agrees with that obtained previously in the membrane paradigm after taking the large D limit.
Damour, Thibault
2016-01-01
On sait qu'Einstein a créé la physique du XXe siècle par ses travaux sur la relativité et les quanta. Mais que sait-on vraiment des idées qu'il a apportées ? Comment les a-t-il trouvées ? A travers des scènes concrètes de la vie d'Einstein, ce livre donne à voir la formation de ses théories. Il nous entraîne aussi dans une réflexion sur leur impact philosophique : comment penser le temps après la théorie de la relativité, qui enlève tout sens au "maintenant" et montre que des jumeaux peuvent ne pas avoir le même âge ? Comment penser la réalité alors que la théorie quantique prédit que des objets spatialement séparés restent liés dans un "enchevêtrement" qui semble défier notre intuition ? Accompagnant Einstein au long de sa vie et de son oeuvre dans un récit limpide et réjouissant, Thibault Damour met à la portée de tous les idées du grand physicien et nous rappelle ce qu'il faut retenir aujourd'hui des bouleversements conceptuels qu'il a introduits.
Levitating soliton of the Bose–Einstein condensate
Energy Technology Data Exchange (ETDEWEB)
Vysotina, N. V.; Rosanov, N. N., E-mail: nnrosanov@mail.ru [Russian Academy of Sciences, Vavilov State Optical Institute (Russian Federation)
2016-07-15
We have proposed a mechanical model that corresponds to the Newton equation for describing the dynamics of an oscillon, viz., a soliton-like cluster of the Bose–Einstein condensate (with atomic attraction) placed above an oscillating atomic mirror in a uniform gravitational field. The model describes the stochastic Fermi acceleration and periodic, quasi-periodic, and chaotic motion of the oscillon center, as well as hysteresis phenomena in the case of a slow variation of mirror oscillation frequency, which are in good agreement with the results obtained using the Gross–Pitaevskii equation.
Investigating tunable KRb gases and Bose-Einstein condensates
DEFF Research Database (Denmark)
Jørgensen, Nils Byg
2015-01-01
We present the production of dual-species Bose-Einstein condensates of 39K and 87Rb with tunable interactions. A dark spontaneous force optical trap was used for 87Rb to reduce the losses in 39K originating from light-assisted collisions in the magneto optical trapping phase. Using sympathetic...... for dual-species condensates with tunable interactions. Employing the dual-species condensates, the miscible to immiscible phase transition was investigated. By applying an empirical model, the transition was used to determine the background scattering length. Two species quantum gases with tunable...
Sensing electric and magnetic fields with Bose-Einstein condensates
DEFF Research Database (Denmark)
Wildermuth, Stefan; Hofferberth, S.; Lesanovsky, Igor
2006-01-01
We experimentally demonstrate that one-dimensional Bose-Einstein condensates brought close to microfabricated wires on an atom chip are a very sensitive sensor for magnetic and electric fields reaching a sensitivity to potential variations of ∼ 10-14 eV at 3 μm spatial resolution. We measure a two......-dimensional magnetic field map 10 μm above a 100-μm-wide wire and show how the transverse current-density component inside the wire can be reconstructed. The relation between the field sensitivity and the spatial resolution is discussed and further improvements utilizing Feshbach-resonances are outlined....
Paul Ehrenfest, Niels Bohr, and Albert Einstein: Colleagues and Friends
Klein, Martin J.
2010-09-01
In May 1918 Paul Ehrenfest received a monograph from Niels Bohr in which Bohr had used Ehrenfest's adiabatic principle as an essential assumption for understanding atomic structure. Ehrenfest responded by inviting Bohr, whom he had never met, to give a talk at a meeting in Leiden in late April 1919, which Bohr accepted; he lived with Ehrenfest, his mathematician wife Tatyana, and their young family for two weeks. Albert Einstein was unable to attend this meeting, but in October 1919 he visited his old friend Ehrenfest and his family in Leiden, where Ehrenfest told him how much he had enjoyed and profited from Bohr's visit. Einstein first met Bohr when Bohr gave a lecture in Berlin at the end of April 1920, and the two immediately proclaimed unbounded admiration for each other as physicists and as human beings. Ehrenfest hoped that he and they would meet at the Third Solvay Conference in Brussels in early April 1921, but his hope was unfulfilled. Einstein, the only physicist from Germany who was invited to it in this bitter postwar atmosphere, decided instead to accompany Chaim Weizmann on a trip to the United States to help raise money for the new Hebrew University in Jerusalem. Bohr became so overworked with the planning and construction of his new Institute for Theoretical Physics in Copenhagen that he could only draft the first part of his Solvay report and ask Ehrenfest to present it, which Ehrenfest agreed to do following the presentation of his own report. After recovering his strength, Bohr invited Ehrenfest to give a lecture in Copenhagen that fall, and Ehrenfest, battling his deep-seated self-doubts, spent three weeks in Copenhagen in December 1921 accompanied by his daughter Tanya and her future husband, the two Ehrenfests staying with the Bohrs in their apartment in Bohr's new Institute for Theoretical Physics. Immediately after leaving Copenhagen, Ehrenfest wrote to Einstein, telling him once again that Bohr was a prodigious physicist, and again
Brownian motion of solitons in a Bose-Einstein condensate.
Aycock, Lauren M; Hurst, Hilary M; Efimkin, Dmitry K; Genkina, Dina; Lu, Hsin-I; Galitski, Victor M; Spielman, I B
2017-03-07
We observed and controlled the Brownian motion of solitons. We launched solitonic excitations in highly elongated [Formula: see text] Bose-Einstein condensates (BECs) and showed that a dilute background of impurity atoms in a different internal state dramatically affects the soliton. With no impurities and in one dimension (1D), these solitons would have an infinite lifetime, a consequence of integrability. In our experiment, the added impurities scatter off the much larger soliton, contributing to its Brownian motion and decreasing its lifetime. We describe the soliton's diffusive behavior using a quasi-1D scattering theory of impurity atoms interacting with a soliton, giving diffusion coefficients consistent with experiment.
Spontaneous symmetry breaking in spinor Bose-Einstein condensates
DEFF Research Database (Denmark)
Scherer, Manuel; Lücke, Bernd; Peise, Jan
2013-01-01
We present an analytical model for the theoretical analysis of spin dynamics and spontaneous symmetry breaking in a spinor Bose-Einstein condensate (BEC). This allows for an excellent intuitive understanding of the processes and provides good quantitative agreement with the experimental results...... in the creation efficiency of these atom pairs can be traced back to excitation modes of this confinement. The understanding of these excitation modes allows for a detailed characterization of the symmetry-breaking mechanism, showing how a twofold spontaneous breaking of spatial and spin symmetry can occur....... In addition, a detailed account of the experimental methods for the preparation and analysis of spinor quantum gases is given....
Geometric phase gate for entangling two Bose-Einstein condensates
Hussain, Mahmood Irtiza; Ilo-Okeke, Ebubechukwu O.; Byrnes, Tim
2014-01-01
We propose a method of entangling two spinor Bose-Einstein condensates using a geometric phase gate. The scheme relies upon only the ac Stark shift and a common controllable optical mode coupled to the spins. Our scheme allows for the creation of an SzSz type interaction where Sz is the total spin. The geometric phase gate can be executed in times of the order of 2{\\pi} /G, where G is the magnitude of the Stark shift. In contrast to related schemes which relied on a fourth order interaction t...
Winding up superfluid in a torus via Bose Einstein condensation
Energy Technology Data Exchange (ETDEWEB)
Das, Arnab [Los Alamos National Laboratory; Sabbatini, Jacopo [Los Alamos National Laboratory; Zurek, Wojciech H [Los Alamos National Laboratory
2010-12-16
We simulate Bose-Einstein condensation at finite temperature in a ring employing stochastic Gross-Pitaevskii equation and show that cooling through the critical point can generate topologically stable quantized circulation of the newborn condensate around the ring. The resulting winding numbers exhibiting Gaussian distribution with dispersion following scaling behavior predicted by the Kibble-Zurek mechanism (KZM). This opens up possibilities for direct experimental study of the underlying phase transition and the basic principles of KZM extended to account for such circulations. We discuss the effect of inhomogeneity on the above phenomenon by considering the effect of tilting of the ring in the gravitational field.
Towards Einstein-Podolsky-Rosen quantum channel multiplexing
Energy Technology Data Exchange (ETDEWEB)
Samblowski, Aiko; Hage, Boris; Schnabel, Roman [Institut fuer Gravitationsphysik, Leibniz Universitaet Hannover und Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institut), Callinstrasse 38, 30167 Hannover (Germany)
2008-07-01
We present an experiment to utilize a single broadband squeezed field as a source for a large number N of quantum channels, based on distributed Einstein-Podolsky-Rosen (EPR) entangled states. Each of those channels can serve as a resource for independent quantum communication protocols. N-fold channel multiplexing can be realized by accessing 2N squeezed modes at different Fourier frequencies of a single squeezed field. We demonstrate the experimental implementation of the N=1 case through the interference of two squeezed modes.
Inflation and accelerated universe based on Bose-Einstein condensation
Morikawa, M.; Fukuyama, T.
A new cosmology based on the Bose-Einstein condensation is proposed. This is a unified model of Dark Energy and Dark Matter, and predicts several collapses of BEC, followed by the final acceleration which successfully describes the recent observational results. Furthermore, this model can be extended to the early inflationary regime, and explains natural initiation of the inflation, autonomous termination of the inflation, inevitable initiation of the reheating process, autonomous adjustment of the cosmological constant to zero, and acceptable generation of density fluctuations.
Accelerating Hilbert-Einstein universe without dynamic dark energy
Energy Technology Data Exchange (ETDEWEB)
Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)]. E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es; Fernandez, Alberto Rozas [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)
2006-10-05
By using an unmodified Einstein gravity theory it is shown that all of the speeding-up effects taking place in the current universe are entirely due to the quantum effects associated with the background radiation or to the combination of such effects with those derived from the presence of a cosmological constant, without invoking any dynamic dark energy component. We obtain that in both cases the universe accelerates at a rate slightly beyond what is predicted by a cosmological constant but does not induce any big rip singularity in the finite future.
Local and Global Existence Theorems for the Einstein Equations
Directory of Open Access Journals (Sweden)
Rendall Alan D.
2000-01-01
Full Text Available This article is a guide to the literature on existence theorems for the Einstein equations which also draws attention to open problems in the field. The local in time Cauchy problem, which is relatively well understood, is treated first. Next global results for solutions with symmetry are discussed. A selection of results from Newtonian theory and special relativity which offer useful comparisons is presented. This is followed by a survey of global results in the case of small data and results on constructing spacetimes with given singularity structure. The article ends with some miscellaneous topics connected with the main theme.
Classical mechanics from Newton to Einstein : a modern introduction
McCall, Martin
2011-01-01
This new edition of Classical Mechanics, aimed at undergraduate physics and engineering students, presents in a user-friendly style an authoritative approach to the complementary subjects of classical mechanics and relativity. The text starts with a careful look at Newton's Laws, before applying them in one dimension to oscillations and collisions. More advanced applications - including gravitational orbits and rigid body dynamics - are discussed after the limitations of Newton's inertial frames have been highlighted through an exposition of Einstein's Special Relativity. Examples gi
Rotating black holes in dilatonic Einstein-Gauss-Bonnet theory.
Kleihaus, Burkhard; Kunz, Jutta; Radu, Eugen
2011-04-15
We construct generalizations of the Kerr black holes by including higher-curvature corrections in the form of the Gauss-Bonnet density coupled to the dilaton. We show that the domain of existence of these Einstein-Gauss-Bonnet-dilaton (EGBD) black holes is bounded by the Kerr black holes, the critical EGBD black holes, and the singular extremal EGBD solutions. The angular momentum of the EGBD black holes can exceed the Kerr bound. The EGBD black holes satisfy a generalized Smarr relation. We also compare their innermost stable circular orbits with those of the Kerr black holes and show the existence of differences which might be observable in astrophysical systems.
Generalized absorber theory and the Einstein-Podolsky-Rosen paradox
Energy Technology Data Exchange (ETDEWEB)
Cramer, J.G.
1980-07-15
A generalized form of Wheeler-Feynman absorber theory is used to explain the quantum-mechanical paradox proposed by Einstein, Podolsky, and Rosen (EPR). The advanced solutions of the electromagnetic wave equation and of relativistic quantum-mechanical wave equations are shown to play the role of ''verifier'' in quantum-mechanical ''transactions,'' providing microscopic communication paths between detectors across spacelike intervals in violation of the EPR locality postulate. The principle of causality is discussed in the context of this approach, and possibilities for experimental tests of the theory are examined.
Einstein SSS+MPC observations of Seyfert type galaxies
Holt, S. S.; Turner, T. J.; Mushotzky, R. F.; Weaver, K.
1989-01-01
The X-ray spectra of 27 Seyfert galaxies measured with the Solid State Spectrometer (SSS) onboard the Einstein Observatory is investigated. This new investigation features the utilization of simultaneous data from the Monitor Proportional Counter (MPC) and automatic correction for systematic effects in the SSS. The new results are that the best-fit single power law indices agree with those previously reported, but that soft excesses are inferred for at least 20 percent of the measured spectra. The soft excesses are consistent with either an approximately 0.25 keV black body or Fe-L line emission.
Great experiments in physics firsthand accounts from Galileo to Einstein
1959-01-01
From Galileo's famous experiments in accelerated motion to Einstein's revolutionary theory of relativity, the experiments recorded here trace the evolution of modern physics from its beginnings to the mid-20th century. Brought together for the first time in one volume are important source readings on 25 epochal discoveries that changed man's understanding of the physical world. The accounts, written by the physicists who made them, include:Issac Newton: The Laws of MotionHenry Cavendish: The Law of GravitationAugustin Fresnel: The Diffraction of LightHans Christian Oersted: ElecromagnetismH
Concepts of Simultaneity From Antiquity to Einstein and beyond
Energy Technology Data Exchange (ETDEWEB)
Muller, F A [Dept. of Physics and Astronomy, Institute for the History and Foundations of Science, Utrecht University, Utrecht University P.O Box 80125, 3508 TC Utrecht (Netherlands)
2007-10-05
Concepts of Simultaneity (henceforth: Simultaneity) is Jammer's historical monograph dedicated to the development of a single concept in physics. Jammer's idea to write a history of concepts of simultaneity proves to be a wonderful idea: it makes Simultaneity literally unique in its kind and it provides a new perspective from which to look at the historical development of concepts of time, about which much has already been written. Anyone who believes that Einstein was the first person on planet Earth to reflect on how to establish whether two distant events have occurred at the same time, i.e. simultaneously, will stop believing this after having read chapters 2 and 3 of Simultaneity (chapter 1 consists of terminological preliminaries), which deal with Antiquity and the Middle Ages, respectively. For example, Augustine of Hippo anticipated, in his Confessions (397 C.E.), nothing less than the method to determine the simultaneity of distant events that we associate with Einstein. Augustine set out to criticise the heresy of astrology. He considered two infants being born simultaneously in distant places. According to the doctrines of astrology they should lead very similar lives, because they are born under the same constellation of the stars. Yet one infant, Augustine imagined, is the child of a poor maid servant whereas the other is the child of a rich lady, so that they would almost certainly lead very different lives. How to know whether the infants are born simultaneously? Augustine proposed to dispatch, at the moment of birth, two messengers who run equally fast from the houses were the babies were born (whether they do run equally fast can be ascertained by using only local simultaneity judgments); the messengers should run towards each other in order to see whether they meet 'at equal distance from either house' (p. 49). If so, the infants were born simultaneously. Of course, this will not be very accurate, but that is not the point. The
Observation of Weak Collapse in a Bose-Einstein Condensate
Directory of Open Access Journals (Sweden)
Christoph Eigen
2016-12-01
Full Text Available We study the collapse of an attractive atomic Bose-Einstein condensate prepared in the uniform potential of an optical-box trap. We characterize the critical point for collapse and the collapse dynamics, observing universal behavior in agreement with theoretical expectations. Most importantly, we observe a clear experimental signature of the counterintuitive weak collapse, namely, that making the system more unstable can result in a smaller particle loss. We experimentally determine the scaling laws that govern the weak-collapse atom loss, providing a benchmark for the general theories of nonlinear wave phenomena.
Observation of Weak Collapse in a Bose-Einstein Condensate
Eigen, Christoph; Gaunt, Alexander L.; Suleymanzade, Aziza; Navon, Nir; Hadzibabic, Zoran; Smith, Robert P.
2016-10-01
We study the collapse of an attractive atomic Bose-Einstein condensate prepared in the uniform potential of an optical-box trap. We characterize the critical point for collapse and the collapse dynamics, observing universal behavior in agreement with theoretical expectations. Most importantly, we observe a clear experimental signature of the counterintuitive weak collapse, namely, that making the system more unstable can result in a smaller particle loss. We experimentally determine the scaling laws that govern the weak-collapse atom loss, providing a benchmark for the general theories of nonlinear wave phenomena.
DE NEWTON A EINSTEIN: A DEBATE EL DESTINO DEL UNIVERSO
Directory of Open Access Journals (Sweden)
ROGELIO PARREIRA
2010-01-01
Full Text Available En este artículo se describe la historia del pensamiento científico en términos de las teorías de la inercia, el espacio absoluto, la relatividad y la gravitación; de cómo Newton utilizó el trabajo de los primeros investigadores en sus teorías, y Einstein las teorías de Newton en la suya, para tratar de explicar el destino del universo. Es la descripción de un proceso revolucionario del conocimiento científico, y sus aportes al desarrollo de muchos otros campos del saber
Bose-Einstein correlations in e/sup +/e/sup -/ collisions
Energy Technology Data Exchange (ETDEWEB)
Juricic, I.
1987-12-01
The MARK II detector is used to study the Bose-Einstein correlation between pairs and triplets of charged pions produced in hadronic decays of the J)psi), the ..sqrt..s = 4 to 7 GeV continuum above the J)psi), two photon events at ..sqrt..s = 29 GeV, and e/sup )plus/)e/sup )minus/) annihilation events at ..sqrt..s = 29 GeV as a function of Q/sup 2/, the four-momentum transfer squared. After corrections for Coulomb effects and pion misidentification, we find a nearly full Bose-Einstein enhancement ..cap alpha.. in the J)psi) and the two photon data and about half the maximum value in the other two data sets. The radius parameter )tau)(an average over space and time) given by pion pair analyses lies within a band of +-0.10 fm around 0.73 fm and is the same, within errors, for all four data sets. Pion triplet analyses also give a consistent radius of approx. 0.54 fm. fits to two-dimensional distributions R(q/sub T//sup 2/, q/sub C//sup 2/) of invariant components of Q/sup 2/ = q/sub T//sup 2/ )plus) q/sub C//sup 2/ give )tau)/sub T/ approx. )tau)C approx. )tau), where q/sub T/ is the transverse three-momentum difference calculated with respect to the net pair three-momentum, and q/sub C/ is in effect the longitudinal three-momentum difference in the pion pair rest frame. When q/sub T/ is calculated with respect to the jet axis for two-jet events in the e/sup )plus/)e/sup )minus/) annihilation data at ..sqrt..s = 29 GeV, a fit to R(q/sub T//sup 2/, q/sub C//sup 2/) also gives )tau)/sub T/ approx. )tau)/sub C/ approx. )tau). Noting that q/sub L/ and q/sub 0/ are not invariant, we make fits to R(/sub T//sup T/, q/sub L//sup 2/) and to R(q/sub T//sup 2/, q/sub 0//sup 2/) (Kopylov formulation), and we find )tau)/sub 0/ approx. )tau)/sub L/ approx. )23))tau)/sub T/ to )12))tau)/sub T/. 44 refs., 43 figs., 15 tabs
Quantum Einstein gravity. Advancements of heat kernel-based renormalization group studies
Energy Technology Data Exchange (ETDEWEB)
Groh, Kai
2012-10-15
The asymptotic safety scenario allows to define a consistent theory of quantized gravity within the framework of quantum field theory. The central conjecture of this scenario is the existence of a non-Gaussian fixed point of the theory's renormalization group flow, that allows to formulate renormalization conditions that render the theory fully predictive. Investigations of this possibility use an exact functional renormalization group equation as a primary non-perturbative tool. This equation implements Wilsonian renormalization group transformations, and is demonstrated to represent a reformulation of the functional integral approach to quantum field theory. As its main result, this thesis develops an algebraic algorithm which allows to systematically construct the renormalization group flow of gauge theories as well as gravity in arbitrary expansion schemes. In particular, it uses off-diagonal heat kernel techniques to efficiently handle the non-minimal differential operators which appear due to gauge symmetries. The central virtue of the algorithm is that no additional simplifications need to be employed, opening the possibility for more systematic investigations of the emergence of non-perturbative phenomena. As a by-product several novel results on the heat kernel expansion of the Laplace operator acting on general gauge bundles are obtained. The constructed algorithm is used to re-derive the renormalization group flow of gravity in the Einstein-Hilbert truncation, showing the manifest background independence of the results. The well-studied Einstein-Hilbert case is further advanced by taking the effect of a running ghost field renormalization on the gravitational coupling constants into account. A detailed numerical analysis reveals a further stabilization of the found non-Gaussian fixed point. Finally, the proposed algorithm is applied to the case of higher derivative gravity including all curvature squared interactions. This establishes an improvement
Einstein and Planck on mass-energy equivalence in 1905-06: a modern perspective
Field, J.H.
2014-01-01
Einstein's theoretical analysis of mass-energy equivalence, already, at the time, experimentally evident in radioactive decays, in two papers published in 1905, as well as Planck's introduction, in 1906, of the concepts of relativistic momentum, and, by invoking Hamilton's Principle, relativistic energy, are reviewed and discussed. Claims in the literature that Einstein's analysis was flawed, lacked generality, or was not rigorous, are rebutted.
Nonexponential one-body loss in a Bose-Einstein condensate
Knoop, S.; Borbely, J. S.; van Rooij, R.; Vassen, W.
2012-01-01
We have studied the decay of a Bose-Einstein condensate (BEC) of metastable helium atoms in an optical dipole trap. In the regime where two- and three-body losses can be neglected we show that the Bose-Einstein condensate and the thermal cloud show fundamentally different decay characteristics. The
Measurement of Genuine Three-Particle Bose-Einstein Correlations in Hadronic Z decay
Achard, P; Aguilar-Benítez, M; Alcaraz, J; Alemanni, G; Allaby, James V; Aloisio, A; Alviggi, M G; Anderhub, H; Andreev, V P; Anselmo, F; Arefev, A; Azemoon, T; Aziz, T; Bagnaia, P; Bajo, A; Baksay, G; Baksay, L; Baldew, S V; Banerjee, S; Banerjee, Sw; Barczyk, A; Barillère, R; Bartalini, P; Basile, M; Batalova, N; Battiston, R; Bay, A; Becattini, F; Becker, U; Behner, F; Bellucci, L; Berbeco, R; Berdugo, J; Berges, P; Bertucci, B; Betev, B L; Biasini, M; Biglietti, M; Biland, A; Blaising, J J; Blyth, S C; Bobbink, Gerjan J; Böhm, A; Boldizsar, L; Borgia, B; Bottai, S; Bourilkov, D; Bourquin, Maurice; Braccini, S; Branson, J G; Brochu, F; Burger, J D; Burger, W J; Cai, X D; Capell, M; Cara Romeo, G; Carlino, G; Cartacci, A M; Casaus, J; Cavallari, F; Cavallo, N; Cecchi, C; Cerrada, M; Chamizo-Llatas, M; Chang, Y H; Chemarin, M; Chen, A; Chen, G; Chen, G M; Chen, H F; Chen, H S; Chiefari, G; Cifarelli, Luisa; Cindolo, F; Clare, I; Clare, R; Coignet, G; Colino, N; Costantini, S; de la Cruz, B; Cucciarelli, S; van Dalen, J A; De Asmundis, R; Déglon, P L; Debreczeni, J; Degré, A; Dehmelt, K; Deiters, K; Della Volpe, D; Delmeire, E; Denes, P; De Notaristefani, F; De Salvo, A; Diemoz, M; Dierckxsens, M; Dionisi, C; Dittmar, Michael; Doria, A; Dova, M T; Duchesneau, D; Echenard, B; Eline, A; El-Mamouni, H; Engler, A; Eppling, F J; Ewers, A; Extermann, Pierre; Falagán, M A; Falciano, S; Favara, A; Fay, J; Fedin, O; Felcini, Marta; Ferguson, T; Fesefeldt, H S; Fiandrini, E; Field, J H; Filthaut, Frank; Fisher, P H; Fisher, W; Fisk, I; Forconi, G; Freudenreich, Klaus; Furetta, C; Galaktionov, Yu; Ganguli, S N; García-Abia, P; Gataullin, M; Gentile, S; Giagu, S; Gong, Z F; Grenier, G; Grimm, O; Grünewald, M W; Guida, M; van Gulik, R; Gupta, V K; Gurtu, A; Gutay, L J; Haas, D; Hakobyan, R S; Hatzifotiadou, D; Hebbeker, T; Hervé, A; Hirschfelder, J; Hofer, H; Hohlmann, M; Holzner, G; Hou, S R; Hu, Y; Jin, B N; Jones, L W; de Jong, P; Josa-Mutuberria, I; Käfer, D; Kaur, M; Kienzle-Focacci, M N; Kim, J K; Kirkby, Jasper; Kittel, E W; Klimentov, A; König, A C; Kopal, M; Koutsenko, V F; Kräber, M H; Krämer, R W; Krenz, W; Krüger, A; Kunin, A; Ladrón de Guevara, P; Laktineh, I; Landi, G; Lebeau, M; Lebedev, A; Lebrun, P; Lecomte, P; Lecoq, P; Le Coultre, P; Le Goff, J M; Leiste, R; Levtchenko, M; Levchenko, P M; Li, C; Likhoded, S A; Lin, C H; Lin, W T; Linde, Frank L; Lista, L; Liu, Z A; Lohmann, W; Longo, E; Lü, Y S; Lübelsmeyer, K; Luci, C; Luminari, L; Lustermann, W; Ma Wen Gan; Malgeri, L; Malinin, A; Maña, C; Mangeol, D J J; Mans, J; Martin, J P; Marzano, F; Mazumdar, K; McNeil, R R; Mele, S; Merola, L; Meschini, M; Metzger, W J; Mihul, A; Milcent, H; Mirabelli, G; Mnich, J; Mohanty, G B; Muanza, G S; Muijs, A J M; Musicar, B; Musy, M; Nagy, S; Natale, S; Napolitano, M; Nessi-Tedaldi, F; Newman, H; Niessen, T; Nisati, A; Nowak, H; Ofierzynski, R A; Organtini, G; Palomares, C; Pandoulas, D; Paolucci, P; Paramatti, R; Passaleva, G; Patricelli, S; Paul, T; Pauluzzi, M; Paus, C; Pauss, Felicitas; Pedace, M; Pensotti, S; Perret-Gallix, D; Petersen, B; Piccolo, D; Pierella, F; Pioppi, M; Piroué, P A; Pistolesi, E; Plyaskin, V; Pohl, M; Pozhidaev, V; Pothier, J; Prokofiev, D O; Prokofev, D; Quartieri, J; Rahal-Callot, G; Rahaman, M A; Raics, P; Raja, N; Ramelli, R; Rancoita, P G; Ranieri, R; Raspereza, A V; Razis, P A; Ren, D; Rescigno, M; Reucroft, S; Riemann, S; Riles, K; Roe, B P; Romero, L; Rosca, A; Rosier-Lees, S; Roth, S; Rosenbleck, C; Roux, B; Rubio, Juan Antonio; Ruggiero, G; Rykaczewski, H; Sakharov, A; Saremi, S; Sarkar, S; Salicio, J; Sánchez, E; Sanders, M P; Schäfer, C; Shchegelskii, V; Schmidt-Kärst, S; Schmitz, D; Schopper, Herwig Franz; Schotanus, D J; Schwering, G; Sciacca, C; Servoli, L; Shevchenko, S; Shivarov, N; Shoutko, V; Shumilov, E; Shvorob, A V; Siedenburg, T; Son, D; Souga, C; Spillantini, P; Steuer, M; Stickland, D P; Stoyanov, B; Strässner, A; Sudhakar, K; Sultanov, G G; Sun, L Z; Sushkov, S V; Suter, H; Swain, J D; Szillási, Z; Tang, X W; Tarjan, P; Tauscher, Ludwig; Taylor, L; Tellili, B; Teyssier, D; Timmermans, C; Ting, Samuel C C; Ting, S M; Tonwar, S C; Tóth, J; Tully, C; Tung, K L; Ulbricht, J; Valente, E; Van de Walle, R T; Vásquez, R P; Veszpremi, V; Vesztergombi, G; Vetlitskii, I; Vicinanza, D; Viertel, Gert M; Villa, S; Vivargent, M; Vlachos, S; Vodopyanov, I; Vogel, H; Vogt, H; Vorobev, I; Vorobyov, A A; Wadhwa, M; Wallraff, W; Wang, X L; Wang, Z M; Weber, M; Wienemann, P; Wilkens, H; Wynhoff, S; Xia, L; Xu, Z Z; Yamamoto, J; Yang, B Z; Yang, C G; Yang, H J; Yang, M; Yeh, S C; Zalite, A; Zalite, Yu; Zhang, Z P; Zhao, J; Zhu, G Y; Zhu, R Y; Zhuang, H L; Zichichi, A; Zimmermann, B; Zöller, M
2002-01-01
We measure three-particle Bose-Einstein correlations in hadronic Z decay with the L3 detector at LEP. Genuine three-particle Bose-Einstein correlations are observed. By comparing two- and three-particle correlations we find that the data are consistent with fully incoherent pion production.
Six Not-So-Easy Pieces Einstein's Relativity, Symmetry, and Space-Time
Feynman, Richard P; Sands, Matthew
2011-01-01
Six lectures, all regarding the most revolutionary discovery in twentieth-century physics: Einstein's Theory of Relativity. No one--not even Einstein himself--explained these difficult, anti-intuitive concepts more clearly, or with more verve and gusto, than Feynman.
How Einstein Discovered the Special Theory of Relativity -R-ES ...
Indian Academy of Sciences (India)
Theory of Relativity. S Banerji. Contrary to what we learn in textbooks on the. Special Theory of Relativity, Michelson-Morley experiment had no direct influence on Einstein's discovery although he ... scientific theories but Einstein questioned the very ax- ioms which formed the .... ship to illustrate his point. If the ether frame ...
On the role of the Michelson–Morley experiment: Einstein in Chicago
van Dongen, J.A.E.F.|info:eu-repo/dai/nl/242629431
2009-01-01
This article discusses new material, published in volume 12 of the Collected Papers of Albert Einstein, that addresses Einstein’s knowledge of the Michelson–Morley experiment prior to 1905: in a lecture in Chicago in 1921, Einstein referred to the experiment, mentioned when he came upon it and
Einstein's and Cassirer's different adoption of the Helmholtzian Tradition of Theoretical Physics
DEFF Research Database (Denmark)
Brock, Steen
2006-01-01
An analysis of Einstein and Ernst Cassirer's different views of the possibility of a general development of theoretical physics, based on a comparison with the view of Niels Bohr.......An analysis of Einstein and Ernst Cassirer's different views of the possibility of a general development of theoretical physics, based on a comparison with the view of Niels Bohr....
van Dongen, J.A.E.F.|info:eu-repo/dai/nl/242629431
2012-01-01
Albert Einstein accepted a “special” visiting professorship at the University of Leiden in the Netherlands in February 1920. Although his appointment should have been a mere formality, it took until October of that year before Einstein could occupy his special chair. Why the delay? The explanation
On the Classical Roots of the Einstein-Podolsky-Rosen Paradox
Lando, A.; Bringuier, E.
2008-01-01
The 1935 debate opposing Einstein, Podolsky and Rosen to Bohr elicited so many comments and developments, both theoretical and experimental, until this day, that the main point at stake at that time can be overlooked by modern readers, especially students. This paper draws the reader's attention to the historical background of Einstein's paper and…
Colloquium: The Einstein-Podolsky-Rosen paradox: From concepts to applications
DEFF Research Database (Denmark)
Reid, M.; Drummond, P.; Bowen, W.
2009-01-01
This Colloquium examines the field of the Einstein, Podolsky, and Rosen (EPR) gedanken experiment, from the original paper of Einstein, Podolsky, and Rosen, through to modern theoretical proposals of how to realize both the continuous-variable and discrete versions of the EPR paradox. The relatio...
DEFF Research Database (Denmark)
Plummer, Ruth; Swaisland, Helen; Leunen, Karin
2015-01-01
formulation. METHODS: PK data were obtained in Part A using a two-treatment period crossover design; single-dose olaparib 300 mg (two 150 mg tablets) was administered in two prandial states: fasted and fed. In Part B, patients received olaparib tablets (300 mg bid) for 5 days under fasting conditions; in Part...... C, patients were allowed continued access to olaparib. Safety was assessed throughout, with data reported for Parts A and B. RESULTS: A total of 60 and 56 patients were evaluable for safety and PK analyses, respectively; 57 patients entered Part B. Rate of olaparib absorption was slower.......16)]. The point estimate and 90 % CI for the AUC0-∞ treatment ratio were within pre-defined bioequivalence limits (0.80-1.25). Adverse event data were consistent with the known safety profile of olaparib. CONCLUSIONS: Results of this study showed that a high-fat meal decreases the rate of absorption and peak...
The "inedito" of Einstein and his 1925 visit to Buenos Aires
Gangui, Alejandro
2008-01-01
In an article published by Mauricio Nirenstein in 1925, a few months after the visit of Albert Einstein to Argentina, the author wrote various comments and references relative to the scientist's visit. In particular, Nirenstein mentioned a personal conversation he had with Einstein in which the sage expressed many interesting ideas on the epistemology of physical sciences. In a note to that article, it was indicated that Einstein would have left in the hands of Nirenstein some notes of a speech he wanted to deliver at the University of Buenos Aires. From 1931 onwards there appeared in a few journals of this city, different versions of what became known as the "inedito" of Einstein. In this paper we discuss both the facts and the individuals. We analyse briefly the "inedito" and we compare it with the two introductory lectures Einstein delivered at the University of Buenos Aires and at the Faculty of Science.
The Einstein@Home search for gravitational waves and neutron stars
CERN. Geneva
2012-01-01
Einstein@Home is a volunteer distributed computing project with more than 300,000 participants. Like other volunteer computing projects, Einstein@Home harvests idle computer cycles from the the laptop and desktop computers of the general public. This provides enormous computing power, on the scale of some of the world's fastest supercomputers, but at very low cost. I describe the current status of the Einstein@Home search for new neutron stars, using data from the Laser Interferometer Gravitational-wave Observatory (LIGO), from the Arecibo and Parkes radio telescopes, and from the Fermi gamma-ray satellite. The sensitivity of these searches is limited by computing power, so the Einstein@Home approach allows the detection of weaker signals than more conventional approaches. In the past 18 months, Einstein@Home has discovered more than 20 new radio and gamma-ray pulsars, including a number of particularly interesting and exotic systems.
Gourgoulhon, Eric
2011-04-01
Numerical relativity is one of the major fields of contemporary general relativity and is developing continually. Yet three years ago, no textbook was available on this subject. The first textbook devoted to numerical relativity, by Alcubierre, appeared in 2008 [1] (cf the CQG review [2]). Now comes the second book, by Baumgarte and Shapiro, two well known players in the field. Inevitably, the two books have some common aspects (otherwise they would not deal with the same topic!). For instance the titles of the first four chapters of Baumgarte and Shapiro are very similar to those of Alcubierre. This arises from some logic inherent to the subject: chapter 1 recaps basic GR, chapter 2 introduces the 3+1 formalism, chapter 3 focuses on the initial data and chapter 4 on the choice of coordinates for the evolution. But there are also many differences between the two books, which actually make them complementary. At first glance the differences are the size (720 pages for Baumgarte and Shapiro vs 464 pages for Alcubierre) and the colour figures in Baumgarte and Shapiro. Regarding the content, Baumgarte and Shapiro address many topics which are not present in Alcubierre's book, such as magnetohydrodynamics, radiative transfer, collisionless matter, spectral methods, rotating stars and post-Newtonian approximation. The main difference regards binary systems: virtually absent from Alcubierre's book (except for binary black hole initial data), they occupy not less than five chapters in Baumgarte and Shapiro's book. In contrast, gravitational wave extraction, various hyperbolic formulations of Einstein's equations and the high-resolution shock-capturing schemes are treated in more depth by Alcubierre. In the first four chapters mentioned above, some distinctive features of Baumgarte and Shapiro's book are the beautiful treatment of Oppenheimer-Snyder collapse in chapter 1, the analogy with Maxwell's equations when discussing the constraints and the evolution equations in
Quantum tunneling of Bose-Einstein condensates in optical lattices
Fan Wen Bin
2003-01-01
In quantum tunneling a particle with energy E can pass through a high potential barrier V(>E) due to the wave character of the particle. Bose-Einstein condensates can display very strong tunneling depending on the structure of the trap, which may be a double-well or optical lattices. The employed for the first time to our knowledge the periodic instanton method to investigate tunneling of Bose-Einstein condensates in optical lattices. The results show that there are two kinds of tunneling in this system, Landau-Zener tunneling between extended states of the system and Wannier-Stark tunneling between localized states of the system, and that the latter is 1000 times faster than the former. The also obtain the total decay rate for a wide range of temperature, including classical thermal activation, thermally assisted tunneling and quantum tunneling. The results agree with experimental data in references. Finally, the propose an experimental protocol to observe this new phenomenon in future experiments
Can we close the Bohr-Einstein quantum debate?
Kupczynski, Marian
2017-11-13
Recent experiments allow one to conclude that Bell-type inequalities are indeed violated; thus, it is important to understand what this means and how we can explain the existence of strong correlations between outcomes of distant measurements. Do we have to announce that Einstein was wrong, Nature is non-local and non-local correlations are produced due to quantum magic and emerge, somehow, from outside space-time? Fortunately, such conclusions are unfounded because, if supplementary parameters describing measuring instruments are correctly incorporated in a theoretical model, then Bell-type inequalities may not be proved. We construct a simple probabilistic model allowing these correlations to be explained in a locally causal way. In our model, measurement outcomes are neither predetermined nor produced in an irreducibly random way. We explain why, contrary to the general belief, the introduction of setting-dependent parameters does not restrict experimenters' freedom of choice. Since the violation of Bell-type inequalities does not allow the conclusion that Nature is non-local and that quantum theory is complete, the Bohr-Einstein quantum debate may not be closed. The continuation of this debate is important not only for a better understanding of Nature but also for various practical applications of quantum phenomena.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).
Einstein and Besso: from Z\\"urich to Milano
Bracco, Christian
2014-01-01
The 1896-1901 Milanese period is a key one to understand Einstein's training background. When he was a student at the ETH in Z\\"urich (the Swiss Federal Polytechnic in Z\\"urich) from 1896 to 1900, he would make regular trips back to Milan to stay with his family who was involved in the development of the electricity industry in northern Italy. Between 1899 and 1901, he would meet his faithful friend and collaborator, Michele Besso in Milan on a regular basis. Given their relationship, the 1899-1901 Milanese period therefore foreshadowed the Bern period later in 1904. In order to specify the circumstances under which Einstein and Besso got the chance to meet, we will show that their respective families did have interconnected social networks, especially through the electricity sector and the polytechnic engineering Universities of Z\\"urich and Milan. The branch of the Cantoni family, on Michele's mother's side, rather ignored by now, played a crucial role: with Vittorio Cantoni, a renowned electrical engineer ...
Spontaneously broken Yang-Mills-Einstein supergravities as double copies
Chiodaroli, Marco; Günaydin, Murat; Johansson, Henrik; Roiban, Radu
2017-06-01
Color/kinematics duality and the double-copy construction have proved to be systematic tools for gaining new insight into gravitational theories. Extending our earlier work, in this paper we introduce new double-copy constructions for large classes of spontaneously-broken Yang-Mills-Einstein theories with adjoint Higgs fields. One gauge-theory copy entering the construction is a spontaneously-broken (super-)Yang-Mills theory, while the other copy is a bosonic Yang-Mills-scalar theory with trilinear scalar interactions that display an explicitly-broken global symmetry. We show that the kinematic numerators of these gauge theories can be made to obey color/kinematics duality by exhibiting particular additional Lie-algebraic relations. We discuss in detail explicit examples with N=2 supersymmetry, focusing on Yang-Mills-Einstein supergravity theories belonging to the generic Jordan family in four and five dimensions, and identify the map between the supergravity and double-copy fields and parameters. We also briefly discuss the application of our results to N=4 supergravity theories. The constructions are illustrated by explicit examples of tree-level and one-loop scattering amplitudes.
Einstein y la filosofía del siglo XX
Directory of Open Access Journals (Sweden)
Sánchez Ron, José Manuel
2007-12-01
Full Text Available The philosophical influences that helped Albert Einstein to build the special relativity theory are studied as his philosophical opinions changed as time passed to adapt to the content of his physics: this characteristic was particularly notorious in connection with the general theory of the relativity. The reception of Einstein’s relativity in the Philosophy World is studied too, first of all in the German-speaking world (Schlick, Cassirer, Reichenbach, Carnap y Popper, next in the British one (Russell, idealism versus realism, then in the US (Bridgman, operationalism and also in the Spanish world (Ortega y Gasset.Se analizan las influencias filosóficas que ayudaron a Albert Einstein en la construcción de la teoría de la relatividad especial, y cómo sus opiniones filosóficas cambiaron con el tiempo para adecuarlas al contenido de su física, un rasgo que es especialmente notorio con relación a la teoría general de la relatividad. Asimismo, se considera la recepción de la relatividad einsteiniana en el mundo filosófico; primero en el de habla alemana (los casos, especialmente, de Schlick, Cassirer, Reichenbach, Carnap y Popper, británico (Russell, idealismo versus realismo, estadounidense (operacionalismo, Bridgman y español (Ortega y Gasset.
The Generalized Conversion Factor in Einstein's Mass-Energy Equation
Directory of Open Access Journals (Sweden)
Ajay Sharma
2008-07-01
Full Text Available Einstein's September 1905 paper is origin of light energy-mass inter conversion equation ($L = Delta mc^{2}$ and Einstein speculated $E = Delta mc^{2}$ from it by simply replacing $L$ by $E$. From its critical analysis it follows that $L = Delta mc^{2}$ is only true under special or ideal conditions. Under general cases the result is $L propto Delta mc^{2}$ ($E propto Delta mc^{2}$. Consequently an alternate equation $Delta E = A ub c^{2}Delta M$ has been suggested, which implies that energy emitted on annihilation of mass can be equal, less and more than predicted by $Delta E = Delta mc^{2}$. The total kinetic energy of fission fragments of U-235 or Pu-239 is found experimentally 20-60 MeV less than Q-value predicted by $Delta mc^{2}$. The mass of particle Ds (2317 discovered at SLAC, is more than current estimates. In many reactions including chemical reactions $E = Delta mc^{2}$ is not confirmed yet, but regarded as true. It implies the conversion factor than $c^{2}$ is possible. These phenomena can be explained with help of generalized mass-energy equation $Delta E = A ub c^{2}Delta M$.
Fast scrambling in holographic Einstein-Podolsky-Rosen pair
Murata, Keiju
2017-11-01
We demonstrate that a holographic model of the Einstein-Podolsky-Rosen pair exhibits fast scrambling. Strongly entangled quark and antiquark in N = 4 super Yang-Mills theory are considered. Their gravity dual is a fundamental string whose endpoints are uniformly accelerated in opposite direction. We slightly increase the acceleration of the endpoint and show that it quickly destroys the correlation between the quark and antiquark. The proper time scale of the destruction is τ ∗ ˜ β ln S where β is the inverse Unruh temperature and S is the entropy of the accelerating quark. We also evaluate the Lyapunov exponent from correlation function as λ L = 2 π/ β, which saturates the Lyapunov bound. Our results suggest that the fast scrambling or saturation of the Lyapunov bound do not directly imply the existence of an Einstein dual. When we slightly decrease the acceleration, the quark and antiquark are causally connected and an "one-way traversable wormhole" is created on the worldsheet. It causes the divergence of the correlation function between the quark and antiquark.
Dynamics of vortex dipoles in confined Bose-Einstein condensates
Energy Technology Data Exchange (ETDEWEB)
Torres, P.J. [Departamento de Matematica Aplicada, Universidad de Granada, 18071 Granada (Spain); Kevrekidis, P.G., E-mail: kevrekid@gmail.com [Department of Mathematics and Statistics, University of Massachusetts, Amherst, MA 01003-4515 (United States); Frantzeskakis, D.J. [Department of Physics, University of Athens, Panepistimiopolis, Zografos, Athens 157 84 (Greece); Carretero-Gonzalez, R. [Nonlinear Dynamical System Group, Computational Science Research Center, and Department of Mathematics and Statistics, San Diego State University, San Diego, CA 92182-7720 (United States); Schmelcher, P. [Zentrum fuer Optische Quantentechnologien, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Hall, D.S. [Department of Physics, Amherst College, Amherst, MA 01002-5000 (United States)
2011-08-01
We present a systematic theoretical analysis of the motion of a pair of straight counter-rotating vortex lines within a trapped Bose-Einstein condensate. We introduce the dynamical equations of motion, identify the associated conserved quantities, and illustrate the integrability of the ensuing dynamics. The system possesses a stationary equilibrium as a special case in a class of exact solutions that consist of rotating guiding-center equilibria about which the vortex lines execute periodic motion; thus, the generic two-vortex motion can be classified as quasi-periodic. We conclude with an analysis of the linear and nonlinear stability of these stationary and rotating equilibria. -- Highlights: → A model describing the motion of a vortex dipole in a quasi two-dimensional trapped Bose-Einstein condensate is considered. → The model is integrable and the generic motion of the dipole is quasi-periodic. → Stationary and periodic (guiding-center) equilibria are identified. → Both equilibria are found to be dynamically stable.
Can we close the Bohr-Einstein quantum debate?
Kupczynski, Marian
2017-10-01
Recent experiments allow one to conclude that Bell-type inequalities are indeed violated; thus, it is important to understand what this means and how we can explain the existence of strong correlations between outcomes of distant measurements. Do we have to announce that Einstein was wrong, Nature is non-local and non-local correlations are produced due to quantum magic and emerge, somehow, from outside space-time? Fortunately, such conclusions are unfounded because, if supplementary parameters describing measuring instruments are correctly incorporated in a theoretical model, then Bell-type inequalities may not be proved. We construct a simple probabilistic model allowing these correlations to be explained in a locally causal way. In our model, measurement outcomes are neither predetermined nor produced in an irreducibly random way. We explain why, contrary to the general belief, the introduction of setting-dependent parameters does not restrict experimenters' freedom of choice. Since the violation of Bell-type inequalities does not allow the conclusion that Nature is non-local and that quantum theory is complete, the Bohr-Einstein quantum debate may not be closed. The continuation of this debate is important not only for a better understanding of Nature but also for various practical applications of quantum phenomena. This article is part of the themed issue `Second quantum revolution: foundational questions'.
Einstein Universe Revisited and End of Dark ERA
Nurgaliev, Ildus S.
2015-01-01
Historically the earliest general relativistic cosmological solution was received by Einstein himself as homogenous, isotropic one. In accordance with European cosmology it was expected static. The Eternal Universe as scientific model is conflicting with the existed theological model of the Universe created by God, therefore, of the limited age. Christianity, younger Islam, older Judaism are based on creationism. Much older oriental traditions such us Hinduism and Buddhism are based on conceptions of eternal and cyclic Universe which are closer to scientific worldview. To have static universe Einstein needed a factor to counteract gravity and postulated cosmological term and considered it as a disadvantage of the theory. This aesthetic dissatisfaction was amplified by interpretation distance-redshift relationship as a cosmological expansion effect. Emerged scientific cosmological community (excluding Hubble himself - almost always) endorsed the concept of expanding Universe. At the same time, as it is shown in this report, a natural well known factors do exist to counteract gravity. They are inertial centrifugal and Coriolis forces finding their geometrical presentation in the relativity theory.
Einsteins of the future on a visit to CERN?
2005-01-01
The five pupils of the Gymnasium Appenzell high school who won a visit to CERN. In 1896 a 17-year-old named Albert Einstein joined ETH Zurich. Here, he was to spend the next four years building the foundation for his brave new vision of the physical world. Fast-forward almost 110 years and on 17 June 2005, ETH Zurich's Department of Physics organized a “Night of Physics”, a special event open to the public. This formed part of a series of activities at ETH to celebrate its 150th anniversary, as well as the World Year of Physics. It gave thousands of visitors a chance to experience the excitement of doing experiments, learning about Einstein's breakthroughs, visiting world-class labs or observing galaxies through high-quality telescopes. Amongst these were about five-hundred high school students from all over German-speaking Switzerland, who participated in a physics competition. They were highly motivated to win, not least because of the first prize: a trip to CERN! The winners visited CERN on the 21st S...
What Costs Do Reveal and Moving beyond the Cost Debate: Reply to Einstein and McDaniel (2010)
Smith, Rebekah E.
2010-01-01
Einstein et al. (2005) predicted no cost to an ongoing task when a prospective memory task met certain criteria. Smith, Hunt, McVay, and McConnell (2007) used prospective memory tasks that met these criteria and found a cost to the ongoing task, contrary to Einstein et al.'s prediction. Einstein and McDaniel (2010) correctly noted that there are…
Plutonium Immobilization Project Baseline Formulation
Energy Technology Data Exchange (ETDEWEB)
Ebbinghaus, B.
1999-02-01
A key milestone for the Immobilization Project (AOP Milestone 3.2a) in Fiscal Year 1998 (FY98) is the definition of the baseline composition or formulation for the plutonium ceramic form. The baseline formulation for the plutonium ceramic product must be finalized before the repository- and plant-related process specifications can be determined. The baseline formulation that is currently specified is given in Table 1.1. In addition to the baseline formulation specification, this report provides specifications for two alternative formulations, related compositional specifications (e.g., precursor compositions and mixing recipes), and other preliminary form and process specifications that are linked to the baseline formulation. The preliminary specifications, when finalized, are not expected to vary tremendously from the preliminary values given.
Baseline LAW Glass Formulation Testing
Energy Technology Data Exchange (ETDEWEB)
Kruger, Albert A. [USDOE Office of River Protection, Richland, WA (United States); Mooers, Cavin [The Catholic University of America, Washington, DC (United States). Vitreous State Lab.; Bazemore, Gina [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Pegg, Ian L. [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Hight, Kenneth [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Lai, Shan Tao [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Buechele, Andrew [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Rielley, Elizabeth [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Gan, Hao [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Muller, Isabelle S. [The Catholic University of America, Washington, DC (United States). Vitreous State Lab; Cecil, Richard [The Catholic University of America, Washington, DC (United States). Vitreous State Lab
2013-06-13
The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements.
TIME AND ETERNITY FROM PLOTINUS AND BOETHIUS TO EINSTEIN
Directory of Open Access Journals (Sweden)
Chase, Michael
2014-01-01
Full Text Available This article seeks to show that the views on time and eternity of Plotinus and Boethius are analogous to those implied by the block-time perspective in contemporary philosophy of time, as implied by the mathematical physics of Einstein and Minkowski. Both Einstein and Boethius utilized their theories of time and eternity with the practical goal of providing consolation to persons in distress; this practice of consolatio is compared to Pierre Hadot’s studies of the “Look from Above”, of the importance of concentrating on the present moment, and his emphasis on ancient philosophy as providing therapy for the soul, instead of mere abstract speculation for its own sake. In the first part of the article, Einstein’s views are compared with those of Plotinus, and with the elucidation of Plotinus’ views provided in the Arabic Theology of Aristotle. The second part of the article studies Boethius’ Consolation of Philosophy, which, contrary to recent interpretations, is indeed a genuine consolation rather than a parody thereof. The Consolation shows how the study of the Neoplatonic philosophical curriculum can lead the student along the path to salvation, by awakening and elaborating his innate ideas. To illustrate this doctrine, a passage from the little-known Pseudo-Boethian treatise De diis et praesensionibus is studied. Finally, after a survey of Boethius’ view on fate and providence, and Aristotle’s theory of future contingents, I study Boethius’ three main arguments in favor of the reconcilability of divine omniscience and human free will: the distinction between absolute and conditional necessity, the principle that the nature of knowledge is determined by the knower, and finally the doctrine that God lives in an eternal present, seeing past, present, and future simultaneously. This last view, developed primarily from Plotinus, is once again argued to be analogous to that advocated by contemporary block-time theorists on the basis
Rowe, David E; Schulmann, Robert
2013-01-01
The most famous scientist of the twentieth century, Albert Einstein was also one of the century's most outspoken political activists. Deeply engaged with the events of his tumultuous times, from the two world wars and the Holocaust, to the atomic bomb and the Cold War, to the effort to establish a Jewish homeland, Einstein was a remarkably prolific political writer, someone who took courageous and often unpopular stands against nationalism, militarism, anti-Semitism, racism, and McCarthyism. In Einstein on Politics, leading Einstein scholars David Rowe and Robert Schulmann gather Einstein's m
The Einstein file J. Edgar Hoover's secret war against the world's most famous scientist
Jerome, Fred
2002-01-01
From the moment of Einstein's arrival in the U.S. in l933 until his death in l955, J. Edgar Hoover's FBI, with help from several other federal agencies, busied itself collecting "derogatory information" in an effort to undermine Einstein's influence and destroy his prestige. For the first time Fred Jerome tells the story of that anti-Einstein campaign, as well as the story behind it--why and how the campaign originated, and thereby provides the first detailed picture of Einstein's little known political activism. Unlike the popular image of Einstein as an absent-minded, head-in-the-clouds genius, the man was in fact intensely politically active and felt it was his duty to use his world-wide fame shrewdly in the cause of social justice. A passionate pacifist, socialist, internationalist and outspoken critic of racism (Einstein considered racism America's "worst disease"), and personal friend of Paul Robeson and W.E.B. DuBois, Einstein used his immense prestige to denounce McCarthy at the height of his power, ...
Saltstone Clean Cap Formulation
Energy Technology Data Exchange (ETDEWEB)
Langton, C
2005-04-22
The current operation strategy for using Saltstone Vault 4 to receive 0.2 Ci/gallon salt solution waste involves pouring a clean grout layer over the radioactive grout prior to initiating pour into another cell. This will minimize the radiating surface area and reduce the dose rate at the vault and surrounding area. The Clean Cap will be used to shield about four feet of Saltstone poured into a Z-Area vault cell prior to moving to another cell. The minimum thickness of the Clean Cap layer will be determined by the cesium concentration and resulting dose levels and it is expected to be about one foot thick based on current calculations for 0.1 Ci Saltstone that is produced in the Saltstone process by stabilization of 0.2 Ci salt solution. This report documents experiments performed to identify a formulation for the Clean Cap. Thermal transient calculations, adiabatic temperature rise measurements, pour height, time between pour calculations and shielding calculations were beyond the scope and time limitations of this study. However, data required for shielding calculations (composition and specific gravity) are provided for shielding calculations. The approach used to design a Clean Cap formulation was to produce a slurry from the reference premix (10/45/45 weight percent cement/slag/fly ash) and domestic water that resembled as closely as possible the properties of the Saltstone slurry. In addition, options were investigated that may offer advantages such as less bleed water and less heat generation. The options with less bleed water required addition of dispersants. The options with lower heat contained more fly ash and less slag. A mix containing 10/45/45 weight percent cement/slag/fly ash with a water to premix ratio of 0.60 is recommended for the Clean Cap. Although this mix may generate more than 3 volume percent standing water (bleed water), it has rheological, mixing and flow properties that are similar to previously processed Saltstone. The recommended
Einstein gravity as a 3D conformally invariant theory
Gomes, Henrique; Koslowski, Tim
2010-01-01
We give an alternative description of the physical content of general relativity that does not require a Lorentz invariant spacetime. Instead, we find that gravity admits a dual description in terms of a theory where local size is irrelevant. The dual theory is invariant under foliation preserving 3-diffeomorphisms and 3D conformal transformations that preserve the 3-volume (for the spatially compact case). Locally, this symmetry is identical to that of Horava-Lifshitz gravity in the high energy limit but our theory is equivalent to Einstein gravity. Specifically, we find that the solutions of general relativity, in a gauge where the spatial hypersurfaces have constant mean extrinsic curvature, can be mapped to solutions of a particular gauge fixing of the dual theory. Moreover, this duality is not accidental. We provide a general geometric picture for our procedure that allows us to trade foliation invariance for conformal invariance. The dual theory provides a new proposal for the theory space of quantum gr...
Thermalization and Bose-Einstein Condensation in Overpopulated Glasma
Energy Technology Data Exchange (ETDEWEB)
Blaizot, Jean-Paul; Gelis, François [Institut de Physique Théorique (URA 2306 du CNRS), CEA/DSM/Saclay, 91191, Gif-sur-Yvette Cedex (France); Liao, Jinfeng [Physics Department and CEEM, Indiana University, 2401 N Milo B. Sampson Lane, Bloomington, IN 47408 (United States); RIKEN BNL Research Center, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States); McLerran, Larry [Physics Department, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States); RIKEN BNL Research Center, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States); Venugopalan, Raju [Physics Department, Bldg. 510A, Brookhaven National Laboratory, Upton, NY 11973 (United States)
2013-05-02
We report recent progress on understanding the thermalization of the quark-gluon plasma during the early stage in a heavy ion collision. The initially high overpopulation in the far-from-equilibrium gluonic matter (“Glasma”) is shown to play a crucial role. The strongly interacting nature (and thus fast evolution) naturally arises as an emergent property of this pre-equilibrium matter where the intrinsic coupling is weak but the highly occupied gluon states coherently amplify the scattering. A possible transient Bose-Einstein Condensate is argued to form dynamically on a rather general ground. We develop a kinetic approach for describing its evolution toward thermalization as well as the onset of condensation.
Optical computing with soliton trains in Bose–Einstein condensates
Pinsker, Florian
2015-07-01
© 2015 World Scientific Publishing Company. Optical computing devices can be implemented based on controlled generation of soliton trains in single and multicomponent Bose-Einstein condensates (BEC). Our concepts utilize the phenomenon that the frequency of soliton trains in BEC can be governed by changing interactions within the atom cloud [F. Pinsker, N. G. Berloff and V. M. Pérez-García, Phys. Rev. A87, 053624 (2013), arXiv:1305.4097]. We use this property to store numbers in terms of those frequencies for a short time until observation. The properties of soliton trains can be changed in an intended way by other components of BEC occupying comparable states or via phase engineering. We elucidate, in which sense, such an additional degree of freedom can be regarded as a tool for controlled manipulation of data. Finally, the outcome of any manipulation made is read out by observing the signature within the density profile.
Bose Einstein condensation of gases in a harmonic potential trap
Directory of Open Access Journals (Sweden)
M. E. Zomorrodian
2005-03-01
Full Text Available One of the most interesting properties of boson gases is that under special conditions, there is a possibility of a phase transition, in a critical temperature below which all bosons condensate into the ground state. This phenomenon is called Bose – Einstein Condensation (BEC. In this paper, we investigate BEC in a harmonic oscillator trap. We conclude that, in contrast to a free boson gas, there is no critical temperature for phase transition in a harmonic oscillator trap. However , by numerical and analytical calculation, it is possible to obtain a temperature at which the heat capacity is maximum. We call this the critical temperature . Possible explanation for all these features will be explained in this paper.
Cohomogeneity-one solutions in Einstein-Maxwell-dilaton gravity
Lim, Yen-Kheng
2017-05-01
The field equations for Einstein-Maxwell-dilaton gravity in D dimensions are reduced to an effective one-dimensional system under the influence of exponential potentials. Various cases where exact solutions can be found are explored. With this procedure, we present interesting solutions such as a one-parameter generalization of the dilaton-Melvin spacetime and a three-parameter solution that interpolates between the Reissner-Nordström and Bertotti-Robinson solutions. This procedure also allows simple, alternative derivations of known solutions such as the Lifshitz spacetime and the planar anti-de Sitter naked singularity. In the latter case, the metric is cast in a simpler form which reveals the presence of an additional curvature singularity.
Bose-Einstein condensation as an alternative to inflation
Das, Saurya
2015-01-01
It was recently shown that gravitons with a very small mass should have formed a Bose-Einstein condensate in the very early Universe, whose density and quantum potential can account for the dark matter and dark energy in the Universe respectively. Here we show that the condensation can also naturally explain the observed large scale homogeneity and isotropy of the Universe. Furthermore gravitons continue to fall into their ground state within the condensate at every epoch, accounting for the observed flatness of space at cosmological distances scales. Finally, we argue that the density perturbations due to quantum fluctuations within the condensate give rise to a scale invariant spectrum. This therefore provides a viable alternative to inflation, which is not associated with the well-known problems associated with the latter.
Vortex dynamics in coherently coupled Bose-Einstein condensates
Calderaro, Luca; Massignan, Pietro; Wittek, Peter
2016-01-01
In classical hydrodynamics with uniform density, vortices move with the local fluid velocity. This description is rewritten in terms of forces arising from the interaction with other vortices. Two such positive straight vortices experience a repulsive interaction and precess in a positive (anticlockwise) sense around their common centroid. A similar picture applies to vortices in a two-component two-dimensional uniform Bose-Einstein condensate (BEC) coherently coupled through rf Rabi fields. Unlike the classical case, however, the rf Rabi coupling induces an attractive interaction and two such vortices with positive signs now rotate in the negative (clockwise) sense. Pairs of counter-rotating vortices are instead found to translate with uniform velocity perpendicular to the line joining their cores. This picture is extended to a single vortex in a two-component trapped BEC. Although two uniform vortex-free components experience familiar Rabi oscillations of particle-number difference, such behavior is absent ...
Josephson effects in a Bose–Einstein condensate of magnons
Energy Technology Data Exchange (ETDEWEB)
Troncoso, Roberto E., E-mail: r.troncoso.c@gmail.com [Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Avda. Ecuador 3493, Santiago 9170124 (Chile); Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile); Núñez, Álvaro S., E-mail: alnunez@dfi.uchile.cl [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile)
2014-07-15
A phenomenological theory is developed, that accounts for the collective dynamics of a Bose–Einstein condensate of magnons. In terms of such description we discuss the nature of spontaneous macroscopic interference between magnon clouds, highlighting the close relation between such effects and the well known Josephson effects. Using those ideas, we present a detailed calculation of the Josephson oscillations between two magnon clouds, spatially separated in a magnonic Josephson junction. -- Highlights: •We presented a theory that accounts for the collective dynamics of a magnon-BEC. •We discuss the nature of macroscopic interference between magnon-BEC clouds. •We remarked the close relation between the above phenomena and Josephson’s effect. •We remark the distinctive oscillations that characterize the Josephson oscillations.
Einstein X-ray observations of M101
Trinchieri, G.; Fabbiano, G.; Romaine, S.
1990-01-01
The Einstein X-ray observations of the face-on spiral galaxy M101 are presented. The global X-ray luminosity L(x) of M101 is about 1.2 x 10 to the 40th ergs/s for D = 7.2 Mpc, consistent with the expected X-ray luminosity of normal spiral galaxies of its optical magnitude. The X-ray emission is mostly due to very luminous individual sources, with L(x) greater than 10 to the 38th ergs/s each, most likely very massive accreting binary systems. The data suggest a deficiency of sources in the luminosity range of L(x) from about 10 to the 37th to about 10 to the 38th ergs/s, which would indicate that the luminosity distribution of the X-ray sources in M101 might be different from that of M31 or M33.
Einstein Observatory coronal temperatures of late-type stars
Schmitt, J. H. M. M.; Collura, A.; Sciortino, S.; Vaiana, G. S.; Harnden, F. R., Jr.
1990-01-01
The results are presented of a survey of the coronal temperatures of late-type stars using the Einstein Observatory IPC. The spectral analysis shows that the frequently found one- and two-temperature descriptions are mainly influenced by the SNR of the data and that models using continuous emission measure distributions can provide equally adequate and physically more meaningful and more plausible descriptions. Intrinsic differences in differential emission measure distributions are found for four groups of stars. M dwarfs generally show evidence for high-temperature gas in conjunction with lower-temperature material, while main-sequence stars of types F and G have the high-temperature component either absent or very weak. Very hot coronae without the lower-temperature component appearing in dwarf stars are evident in most of the giant stars studied. RS CVn systems show evidence for extremely hot coronae, sometimes with no accompanying lower-temperature material.
Are Einstein's transition probabilities for spontaneous emission constant in plasmas?
Griem, H. R.; Huang, Y. W.; Wang, J.-S.; Moreno, J. C.
1991-01-01
An investigation is conducted with a ruby laser to experimentally confirm the quenching of spontaneous emission coefficients and propose a mechanism for the phenomenon. Results of previous experiments are examined to determine the consistency and validity of interpretations of the spontaneous emissions. For the C IV 3s-3p and 2s-3p transitions, the line-intensity ratios are found to be dependent on the separation of the laser from the target. Density gradients and Stark broadening are proposed to interpret the results in a way that does not invalidate the Einstein A values. The interpretation is extended to C III and N V, both of which demonstrate similar changes in A values in previous experiments. The apparent quenching of Ar II by photon collisions is explained by Rabi oscillations and power broadening in the argon-ion laser cavity. It is concluded that the changes in A values cannot result from dense plasma effects.
Einstein Coefficients and Equilibrium Formalism for Tachyon Radiation
Tomaschitz, R
2001-01-01
The spectral energy density of an ideal Bose gas of superluminal particles (tachyons) is derived. To this end, we consider atoms in equilibrium with tachyon radiation, study spontaneous and induced transitions effected by tachyons, calculate the Einstein coefficients, all semiclassically, and obtain, by detailed balancing, the equilibrium distribution of the tachyon gas. Tachyons are described by a real Proca field with negative mass square, coupled to a current of subluminal matter. Atomic transitions induced by tachyons are compared to photonic ones, and the tachyonic analog to the photoelectric effect is discussed. The cosmic tachyon background is scrutinized in detail; high- and low-temperature expansions of the internal energy, the entropy, the heat capacities, and the number density are compared with the corresponding quantities of the photon background. The negative mass square in the wave equation changes the frequency scaling in the Rayleigh-Jeans law, and there are also significant changes in the lo...
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
Modifications of Einstein's theory of gravity at large distances
2015-01-01
In the last few years modified gravity theories have been proposed as extensions of Einstein's theory of gravity. Their main motivation is to explain the latest cosmological and astrophysical data on dark energy and dark matter. The study of general relativity at small scales has already produced important results (cf e.g. LNP 863 Quantum Gravity and Quantum Cosmology) while its study at large scales is challenging because recent and upcoming observational results will provide important information on the validity of these modified theories. In this volume, various aspects of modified gravity at large scales will be discussed: high-curvature gravity theories; general scalar-tensor theories; Galileon theories and their cosmological applications; F(R) gravity theories; massive, new massive and topologically massive gravity; Chern-Simons modifications of general relativity (including holographic variants) and higher-spin gravity theories, to name but a few of the most important recent developments. Edite...
Quantum Rabi model in a superfluid Bose-Einstein condensate
Felicetti, S.; Romero, G.; Solano, E.; Sabín, C.
2017-09-01
We propose a quantum simulation of the quantum Rabi model in an atomic quantum dot, which is a single atom in a tight optical trap coupled to the quasiparticle modes of a superfluid Bose-Einstein condensate. This widely tunable setup allows us to simulate the ultrastrong coupling regime of light-matter interaction in a system which enjoys an amenable characteristic time scale, paving the way for an experimental analysis of the transition between the Jaynes-Cummings and the quantum Rabi dynamics using cold-atom systems. Our scheme can be naturally extended to simulate multiqubit quantum Rabi models. In particular, we discuss the appearance of effective two-qubit interactions due to phononic exchange, among other features.