Chiral String-Soliton Model for the light chiral baryons
Pavlovsky, Oleg
2010-01-01
The Chiral String-Soliton Model is a joining of the two notions about the light chiral baryons: the chiral soliton models (like the Skyrme model) and the Quark-Gluon String models. The ChSS model is based on the Effective Chiral Lagrangian which was proposed in [arXiv:hep-ph/0306216]. We have studied the physical properties of the light chiral baryon within the framework of this ChSS model.
Solitons in nonlocal chiral quark models
Broniowski, W; Ripka, G; Broniowski, Wojciech; Golli, Bojan; Ripka, Georges
2002-01-01
Properties of hedgehog solitons in a chiral quark model with nonlocal regulators are described. We discuss the formation of the hedgehog soliton, the quantization of the baryon number, the energetic stability, the gauging and construction of Noether currents with help of path-ordered P-exponents, and the evaluation of observables. The issue of nonlocality is thoroughly discussed, with a focus on contributions to observables related to the Noether currents. It is shown that with typical model parameters the solitons are not far from the weak nonlocality limit. The methods developed are applicable to solitons in models with separable nonlocal four-fermion interactions.
Cranking the chiral soliton bag model
Stern, J.; Bourenane, M.; Clement, G.
1988-10-01
The nucleon-delta mass difference is computed in the chiral soliton bag model with soft confinement of gluons by the cranking method. The resulting value of the effective strong fine structure constant is ..cap alpha../sub s/ approx. 0.7.
Structure Functions from Chiral Soliton Models
Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Reinhardt, H.
1997-01-01
We study nucleon structure functions within the bosonized Nambu-Jona-Lasinio (NJL) model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron-nucleon scattering. A comparison with a low-scale parametrization shows that the model reproduces the gross features of the empirical structure functions. We also compute the leading twist contributions of the polarized structure functions $g_{1}(x)$ and $g_{2}(x)$ in this model. We compa...
Nucleon-antinucleon annihilation in chiral soliton model
We investigate annihilation process of nucleons in chiral soliton model by path integral method. Soliton-antisoliton pair is shown to decay into pions at range of order of about 1 fm, defined by SS-bar potential. Contribution of annihilation channel into elastic scattering is discussed. (author). 14 refs, 1 fig
Nucleon-antinucleon annihilation in chiral soliton model
We investigate annihilation process of nucleons in the chiral soliton model by the path integral method. A soliton-antisoliton pair is shown to decay into mesons at range of about 1fm, defined by the S bar S potential. Contribution of the annihilation channel to the elastic scattering is discussed
Chiral soliton model vs. pentaquark structure for (1540)
R Ramachandran
2005-09-01
The exotic baryon + (1540 MeV) is visualized as an expected (iso) rotational excitation in the chiral soliton model. It is also argued as a pentaquark baryon state in a constituent quark model with strong diquark correlations. I contrast these two points of view; observe the similarities and differences between the two pictures. Collective excitation, the characteristic of chiral soliton model, points toward small mixing of representations in the wake of (3) breaking. In contrast, constituent quark models prefer near `ideal' mixing, similar to - mixing.
The baryon number two system in the Chiral Soliton Model
Sarti, Valentina Mantovani; Vento, Vicente; Park, Byung-Yoon
2012-01-01
We study the interaction between two B = 1 states in a Chiral Soliton Model where baryons are described as non-topological solitons. By using the hedgehog solution for the B = 1 states we construct three possible B = 2 configurations to analyze the role of the relative orientation of the hedgehog quills in the dynamics. The strong dependence of the intersoliton interaction on these relative orientations reveals that studies of dense hadronic matter using this model should take into account their implications.
Nucleon Structure Functions within a Chiral Soliton Model
Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Reinhardt, H.; Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa)
1997-01-01
We study nucleon structure functions within the bosonized Nambu--Jona--Lasinio model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron--nucleon scattering. A comparison with a low--scale parametrization shows that the model reproduces the gross features of the empirical structure functions. We also compute the leading twist contributions of the polarized structure functions $g_{1}(x)$ and $g_{2}(x)$ in this model. We compare...
Studying the baryon properties through chiral soliton model at finite temperature and denstity
Shu, Song; Li, Jia-Rong
2014-01-01
We have studied the chiral soliton model in a thermal vacuum. The soliton equations are solved at finite temperature and density. The temperature or density dependent soliton solutions are presented. The physical properties of baryons are derived from the soliton solutions at finite temperature and density. The temperature or density dependent variation of the baryon properties are discussed.
Nucleon Structure Functions within a Chiral Soliton Model
Gamberg, L P; Weigel, H
1997-01-01
We study nucleon structure functions within the bosonized Nambu--Jona--Lasinio model where the nucleon emerges as a chiral soliton. We discuss the model predictions on the Gottfried sum rule for electron--nucleon scattering. A comparison with a low--scale parametrization shows that the model reproduces the gross features of the empirical structure functions. We also compute the leading twist contributions of the polarized structure functions $g_{1}(x)$ and $g_{2}(x)$ in this model. We compare the model predictions on these structure functions with data from the E143 experiment by GLAP evolving them appropriately.
Confined Chiral Solitons in the Spectral Quark Model
Ruiz-Arriola, E; Golli, B; Arriola, Enrique Ruiz; Broniowski, Wojciech; Golli, Bojan
2006-01-01
Chiral solitons with baryon number one are investigated in the spectral quark model. In this model the quark propagator is a superposition of complex mass propagators with a suitable spectral function. As a result, the constituent quark mass is identified with saddle points of the Dirac eigenvalues. Due to this feature the valence quarks never become unbound nor dive into the negative spectrum, hence providing stable solitons as absolute minima of the action. This a manifestation of the built-in analytic confinement in the spectral quark model. Self-consistent mean field hedgehog solutions are found and some of their properties determined. Our analysis constitutes an example of a treatment of a relativistic complex mass system.
Solitons in a chiral quark model with non-local interactions
Golli, B; Ripka, G; Golli, Bojan; Broniowski, Wojciech; Ripka, Georges
1998-01-01
Hedgehog solitons are found in a chiral quark model with non-local interactions. The solitons are stable without the chiral-circle constraint for the meson fields, as was assumed in previous Nambu-Jona--Lasinio model with local interactions.
The baryon mass calculation in the chiral soliton model at finite temperature and density
In the mean-field approximation, we have studied the soliton which is embedded in a thermal medium within the chiral soliton model. The energy of the soliton or the baryon mass in the thermal medium has been carefully evaluated, in which we emphasize that the thermal effective potential in the soliton energy should be properly treated in order to derive a finite and well-defined baryon mass out of the thermal background. The result of the baryon mass at finite temperatures and densities in chiral soliton model are clearly presented. (author)
Instability of the hedgehog shape for the octet baryon in the chiral quark soliton model
Akiyama, S; Akiyama, Satoru; Futami, Yasuhiko
2003-01-01
In this paper the stability of the hedgehog shape of the chiral soliton is studied for the octet baryon with the SU(3) chiral quark soliton model. The strangeness degrees of freedom are treated by a simplified bound-state approach, which omits the locality of the kaon wave function. The mean field approximation for the flavor rotation is applied to the model. The classical soliton changes shape according to the strangeness. The baryon appears as a rotational band of the combined system of the deformed soliton and the kaon.
Chiral Quark Soliton Model and Nucleon Spin Structure Functions
Wakamatsu, M
2009-01-01
The chiral quark soliton model (CQSM) is one of the most successful models of baryons at quark level, which maximally incorporates the most important feature of low energy QCD, i.e. the chiral symmetry and its spontaneous breakdown. Basically, it is a relativistic mean-field theory with full account of infinitely many Dirac-sea quarks in a rotational-symmetry-breaking mean field of hedgehog shape. The numerical technique established so far enables us to make a nonperturbative evaluation of Casimir effects (i.e. effects of vacuum-polarized Dirac sea) on a variety of baryon observables. This incompatible feature of the model manifests most clearly in its predictions for parton distribution functions of the nucleon. In this talk, after briefly reviewing several basic features of the CQSM, we plan to demonstrate in various ways that this unique model of baryons provides us with an ideal tool for disentangling nonperturbative aspect of the internal partonic structure of the nucleon, especially the underlying spin ...
Soliton Solutions of the Integrable Chiral Model in 2+1 Dimensions
Ioannidou, Theodora
1997-01-01
We present soliton and soliton-antisoliton solutions for the integrable chiral model in 2+1 dimensions with nontrivial (elastic) scattering. These solutions can be obtained either as the limiting cases of the ones already constructed by Ward or by adapting Uhlenbeck's method.
On the Chiral Quark Soliton Model with Pauli-Villars Regularization
Kubota, T.; Wakamatsu, M.; Watabe, T.
1999-01-01
The Pauli-Villars regularization scheme is often used for evaluating parton distributions within the framework of the chiral quark soliton model with inclusion of the vacuum polarization effects. Its simplest version with a single subtraction term should however be taken with some caution, since it does not fully get rid of divergences contained in scalar and psuedoscalar quark densities appearing in the soliton equation of motion. To remedy this shortcoming, we propose here its natural exten...
Non-local regularization of chiral quark models in the soliton sector
Ripka, G; Ripka, Georges; Golli, Bojan
1999-01-01
A chiral quark model is described which is regularized in terms of Lorentz invariant non-local interactions. The model is regularized to all loop orders and it ensures the proper quantization of the baryon number. It sustains bound hedgehog solitons which, after suitable centre of mass corrections, can adequately describe the nucleon.
Quantum solitons of the nonlinear sigma-model with broken chiral symmetry
Kostyuk, A P; Chepilko, N M; Okazaki, T
1995-01-01
It is proved that the quantum-mechanical consideration of global breathing of a hedgehog-like field configuration leads to the dynamically stable soliton solutions in the nonlinear sigma-model without the Skyrme term. Such solutions exist only when chiral symmetry of the model is broken.
The B=2 system in the chiral quark-soliton model with broken scale invariance
Sarti, Valentina Mantovani; Vento, Vicente
2013-01-01
We study the interaction between two B=1 states in the Chiral-Dilaton Model with scale invariance where baryons are described as non-topological solitons arising from the interaction of chiral mesons and quarks. By using the hedgehog solution for the B=1 states we construct, via a product ansatz, three possible B=2 configurations to analyse the role of the relative orientation of the hedgehog quills in the dynamics. We investigate the behaviour of these solutions in the range of long and intermediate distances between the two solitons. Since the product ansatz breaks down as the two solitons get close, we explore the short range distances regime by building up a six quarks bag and by evaluating the interaction energy as a function of the inter-soliton separation. We calculate the interaction energy as a function of the inter-soliton distance for the B=2 system and we show that for small separations the six quarks bag, assuming a hedgehog structure, provides a stable bound state that at large separations conne...
Chiral solitons a review volume
1987-01-01
This review volume on topological and nontopological chiral solitons presents a global view on the current developments of this field in particle and nuclear physics. The book addresses problems in quantization, restoration of translational and rotational symmetry, and the field theoretical approach to solitons which are common problems in the field of solitons. Primarily aimed for graduate students and the novice in the field, the collected articless cover a broad spectrum of topics in formalism as well as phenomenology.
The projected chiral soliton model with vector mesons
We investigate the solitonic sector of the massive Yang-Mills Lagrangian including σ-, π-, ω-, ρ-, A-mesons as well as valence quarks and apply it to the calculation of some baryonic properties. We perform the canonical quantization which requires the explicit elimination of the time-like components of the vector fields. A mean-field Fock state with hedgehog symmetry is defined as a product of a Slater determinant for the quarks in a 1s-state and coherent states for the mesons. We project this mean-field Fock state onto good spin and isospin by means of Peierls-Yoccoz operators and obtain, after fitting the nucleon mass, a NΔ splitting which is about 80% of the experimental value. A good description of electromagnetic and axial static properties as well as form factors of the nucleon is achieved. Furthermore, the spin content of the nucleon is analyzed in terms of the flavor singlet axial vector coupling constant giving g0A similar 0.44 independently of the input parameters. Finally, the proton-neutron hadronic mass spitting is estimated in the model giving Mn-Mp=2.38±0.55 MeV, the errors reflecting the uncertainty in the up and down quark masses. (orig.)
Energy-Momentum Tensor Form Factors of the Nucleon in Nuclear Matter in the Chiral Soliton Model
Yakhshiev, Ulugbek; Kim, Hyun-Chul; Schweitzer, Peter
2013-08-01
In the present talk, we report a recent investigation on the nucleon form factors of the energy-momentum tensor in nuclear matter, based on the in-medium modified chiral soliton model. The results in free space are in agreement with those from other approaches. We have discussed the changes of the energy-momentum tensor form factors in nuclear matter and the modification of the soliton structure due to the surrounding nuclear environment.
Form factors, medium effects and vector mesons in the projected chiral soliton model
The main goal of the present work has been the evaluation of baryonic form factors by means of the projected chiralquark-meson soliton model and various generalizations of it. In first place we have studied the Nambu-Jona-Lasinio model in the Hartree approximation for classical non-strange scalar and pseudoscalar couplings in the vacuum sector. In doing so, we have first bosonized the Lagrangian and applied three regularization schemes in order to render the theory finite. We have found that at least two physical quantities as the quark mass and the quark condensate are very sensitive to the actual scheme used. The procedures which allow to reproduce best the experimental values are both sharp cut-off methods. We have also shown that the chiral soliton model with explicit valence quarks can be considered as an approximation to the Hartree solution of the Nambu-Jona-lasinio model for quarks. In the framework of the linear chiral sigma model with quarks, sigma-, and pi-mesons we have discussed several nucleon form factors such as electromagnetic, axial and that for the pion-nucleon interaction. (orig./HSI)
Nucleon Structure Functions from a Chiral Soliton
Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Reinhardt, H.
1996-01-01
Nucleon structure functions are studied within the chiral soliton approach to the bosonized Nambu-Jona-Lasinio model. The valence quark approximation is employed which is justified for moderate constituent quark masses ($\\sim$ 400 MeV) as the contribution of the valence quark level dominates the predictions of nucleon properties. As examples the unpolarized structure functions for the ${\
Akiyama, S; Akiyama, Satoru; Futami, Yasuhiko
2006-01-01
Mesonic fluctuations around the chiral solitons are investigated in the SU(3) chiral quark soliton model. Since the soliton takes the non-hedgehog shape for the hyperons and the hedgehog one for the non-hedgehog baryons in our approach, the fluctuations also change according to the baryonic state. The quantum corrections to the masses (the Casimir energies) are estimated for the octet and decuplet baryons. The lack of the confinement in this model demands the cutoff on the energy of the fluctuations. Under the assumption that the value of the cutoff energy is $2\\times$(the lightest constituent quark mass), these calculation reproduces the masses of the baryons within 15 % error.
On Exotic Systems of Baryons in Chiral Soliton Models
Kopeliovich, Vladimir
2016-01-01
The role of zero mode quantum corrections to the energy of baryonic systems with exotic quantum numbers (strangeness) is discussed. A simple expression for the contribution depending on strange inertia is obtained in the $SU(3)-$collective coordinate quantization approach, and it is shown that this correction stabilizes the systems the stronger the greater their baryon number is. Furthemore, systems are considered which could be interpreted in the quark model language as containing additional $q\\bar q-$pairs. It is argued that a strange skyrmion crystal should have additional binding in comparison with the $SU(2)-$quantized neutron crystal.
Sensitivity to properties of the phi-meson in the nucleon structure in the chiral soliton model
Mukhopadhyay, N.C.; Zhang, L. [Rensselaer Polytechnic Inst., Troy, NY (United States)
1994-04-01
The influence of the {phi}-meson on the nucleon properties in the chiral soliton model is discussed. Properties of the {phi}-meson and its photo- and electroproduction are of fundamental interest to CEBAF and its possible future extension. The quark model assigns {phi} an s{bar s} structure, thus forbidding the radiative decay {phi}{yields}{pi}{sup 0}{gamma}. Experimentally it is also found to be suppressed, yielding a branching fraction of 1.3{times}10{sup {minus}3}. However, {phi}{yields}{rho}{pi} and {phi}{yields}{pi}{sup +}{pi}{sup {minus}}{pi}{sup 0} are not suppressed at all. Thus, it is possible to incorporate the widths of these decays into the framework of the chiral soliton model, by making use of a specific model for the compliance with OZI rule. Such a model is for example, the {omega}-{phi} mixing model. Consequence of this in the context of a chiral soliton model, which builds on the {pi}{rho}{omega}a{sub 1}(f{sub 1}) meson effective Lagrangian, is the context of this report.
The role of the Delta isobar in chiral perturbation theory and hedgehog soliton models
Cohen, Thomas D.; Broniowski, Wojciech
1992-01-01
Hedgehog model predictions for the leading nonanalytic behavior (in $m^{2}_{\\pi }$) of certain observables are shown to agree with the predictions of chiral perturbation theory up to an overall factor which depends on the operator. This factor can be understood in terms of contributions of the $\\Delta$ isobar in chiral loops. These physically motivated contributions are analyzed in an expansion in which both $m_{\\pi}$ and $M_{\\Delta}-M_N$ are taken as small parameters, and are shown to yield ...
Gluonic contribution to the nucleon-delta mass difference in a chiral soliton bag model
Bourenane, M.; Stern, J.; Clement, G.
1988-05-01
A generalization of the Friedberg-Lee model, which minimally incorporates soft confinement of quarks and gluons and approximate chiral symmetry, is presented and applied to the computation of the gluonic contribution to the nucleon-delta mass difference. The value of the effective strong fine structure constant is estimated to be ..cap alpha../sub s/=0.65.
Chiral solitons in a coupled double Peierls chain.
Cheon, Sangmo; Kim, Tae-Hwan; Lee, Sung-Hoon; Yeom, Han Woong
2015-10-01
Chiral edge states are the hallmark of two- and three-dimensional topological materials, but their one-dimensional (1D) analog has not yet been found. We report that the 1D topological edge states, solitons, of the charge density wave system of indium atomic wires self-assembled on a silicon surface have chirality. The system is described by a coupled double Peierls-dimerized atomic chain, where the interchain coupling induces dynamical sublattice symmetry breaking. This changes its topological symmetry from Z₂× Z₂to Z₄ and endows solitons with a chiral degree of freedom. Chiral solitons can produce quantized charge transport across the chain that is topologically protected and controllable by the soliton's chirality. Individual right- and left-chiral solitons in indium wires are directly identified by scanning tunneling microscopy. PMID:26450206
A chiral soliton model constrained by gA/gV
We present one example of a smooth chiral confinement model of the nucleon constrained (within a mean-field theory) by the measured gA/gV of the neutron. The resulting confining scalar potential for the quarks inside the nucleon has a maximum in the surface and approaches its asymptotic value from above. Low-energy properties of the nucleon (three quarks in their ground state) are not spoiled by this peculiar surface behaviour. The 'helicity argument' (only spin-carrying fields inside the nucleon contribute to gA/gV) we employed here further, sheds new light on the modelling of the hadrons in terms of hybrid skyrmions and on the description of the Nπ decay mode of excited baryon states
$\\Delta$(1232) electroproduction amplitudes in chiral soliton models of the nucleon
Amoreira, L; Fiolhais, M; Amoreira, Luis; Alberto, Pedro; Fiolhais, Manuel
2000-01-01
The multipole amplitudes for the N - Delta electromagnetic transition are computed in the framework of the linear sigma model and the chiral chromodielectric model for small and moderate photon virtualities. The models include quark and meson degrees of freedom and the nucleon and the delta are clusters of three valence hedgehog quarks surrounded by meson clouds described by coherent states. Angular momentum and isospin projections are performed to endow model states representing the nucleon and the delta with proper quantum numbers. Recoil corrections involved in the process $\\gamma_{\\rm v} N \\to \\Delta$ are taken into account by performing linear momentum projection of the initial and final baryon states. The ratios $E2/M1$ and $C2/M1$ are in good agreement with the data in the two models, but the magnetic amplitude is better reproduced in the Linear Sigma Model. The ratios show little dependence with the model parameters. Both in the Linear Sigma Model and in the Chromodielectric Model the charged pions ar...
Quantum stabilization of the chiral soliton
The SU(2)xSU(2) nonlinear σ-model soliton, stabilized by quantum fluctuations alone, is analyzed by variational calculations. The magnetic moments and gA of the nucleon are calculated and the results are as good as, or better than, with the conventional Skyrmion. It is also pointed out, however, that the model has the wrong Nc dependence for the mass and the size of the soliton, which collapses as the number of colors Nc→∞
Scaling behaviour of the effective chiral action and stability of the chiral soliton
The effective chiral action is evaluated within a novel improved heat-kernel expansion, which includes gradients of the chiral field in a non-perturbative way. The exact scaling behaviour of the effective action of a localized chiral field with respect to changing its spatial size is found. From this it is proved that the radiatively induced derivative terms cannot absolutely stabilize the chiral soliton against collapsing. The collapsing of the soliton is, however, accompanied by a vanishing of the baryon charge. It is argued that the effective chiral action constrained to a fixed baryon number may still admit stable soliton configurations. (orig.)
H Weigel
2003-11-01
In this talk I review studies of hadron properties in bosonized chiral quark models for the quark ﬂavor dynamics. Mesons are constructed from Bethe–Salpeter equations and baryons emerge as chiral solitons. Such models require regularization and I show that the two-fold Pauli–Villars regularization scheme not only fully regularizes the effective action but also leads the scaling laws for structure functions. For the nucleon structure functions the present approach serves to determine the regularization prescription for structure functions whose leading moments are not given by matrix elements of local operators. Some numerical results are presented for the spin structure functions.
Quasi two-dimensional astigmatic solitons in soft chiral metastructures.
Laudyn, Urszula A; Jung, Paweł S; Karpierz, Mirosław A; Assanto, Gaetano
2016-01-01
We investigate a non-homogeneous layered structure encompassing dual spatial dispersion: continuous diffraction in one transverse dimension and discrete diffraction in the orthogonal one. Such dual diffraction can be balanced out by one and the same nonlinear response, giving rise to light self-confinement into astigmatic spatial solitons: self-focusing can compensate for the spreading of a bell-shaped beam, leading to quasi-2D solitary wavepackets which result from 1D transverse self-localization combined with a discrete soliton. We demonstrate such intensity-dependent beam trapping in chiral soft matter, exhibiting one-dimensional discrete diffraction along the helical axis and one-dimensional continuous diffraction in the orthogonal plane. In nematic liquid crystals with suitable birefringence and chiral arrangement, the reorientational nonlinearity is shown to support bell-shaped solitary waves with simple astigmatism dependent on the medium birefringence as well as on the dual diffraction of the input wavepacket. The observations are in agreement with a nonlinear nonlocal model for the all-optical response. PMID:26975651
Quasi two-dimensional astigmatic solitons in soft chiral metastructures
Laudyn, Urszula A.; Jung, Paweł S.; Karpierz, Mirosław A.; Assanto, Gaetano
2016-03-01
We investigate a non-homogeneous layered structure encompassing dual spatial dispersion: continuous diffraction in one transverse dimension and discrete diffraction in the orthogonal one. Such dual diffraction can be balanced out by one and the same nonlinear response, giving rise to light self-confinement into astigmatic spatial solitons: self-focusing can compensate for the spreading of a bell-shaped beam, leading to quasi-2D solitary wavepackets which result from 1D transverse self-localization combined with a discrete soliton. We demonstrate such intensity-dependent beam trapping in chiral soft matter, exhibiting one-dimensional discrete diffraction along the helical axis and one-dimensional continuous diffraction in the orthogonal plane. In nematic liquid crystals with suitable birefringence and chiral arrangement, the reorientational nonlinearity is shown to support bell-shaped solitary waves with simple astigmatism dependent on the medium birefringence as well as on the dual diffraction of the input wavepacket. The observations are in agreement with a nonlinear nonlocal model for the all-optical response.
Silva, A; Kim, H C; Urbano, D; Goeke, Klaus; Kim, Hyun-Chul; Silva, Antonio; Urbano, Diana
2006-01-01
We investigate parity-violating electroweak asymmetries in the elastic scattering of polarized electrons off protons within the framework of the chiral quark-soliton model ($\\chi$QSM). We use as input the former results of the electromagnetic and strange form factors and newly calculated SU(3) axial-vector form factors, all evaluated with the same set of four parameters adjusted several years ago to general mesonic and baryonic properties. Based on this scheme, which yields positive electric and magnetic strange form factors with a $\\mu_s=(0.08-0.13)\\mu_N$, we determine the parity-violating asymmetries of elastic polarized electron-proton scattering. The results are in a good agreement with the data of the A4, HAPPEX, and SAMPLE experiments and reproduce the full $Q^2$-range of the G0-data. We also predict the parity-violating asymmetries for the backward G0 experiment.
Three-Dimensional Topological Solitons in Chiral Liquid Crystals and Ferromagnetic Colloids
Smalyukh, Ivan
Three-dimensional knotted solitons - often called ``hopfions'' - have continuous physical fields classified by the Hopf index topological invariant and behave like particles. These hopfions arise in theories in many branches of physics, but their structure and stability are rarely accessible to direct experimental studies. We realize and characterize such static solitons in the molecular alignment fields of chiral liquid crystals and in the magnetization field of colloids with long-range ferromagnetic ordering. Our experiments agree with predictions of numerical modeling based on free energy minimization. By exploiting facile response of the soft matter host media, we demonstrate exquisite control of structure and tunable self-assembly of such solitonic ``particles''. This lecture will discuss how liquid crystals and colloids can serve as soft matter model systems in studies of structure, topology and dynamics of three-dimensional topological solitons. Gsoft Early Career.
Gravitating $\\sigma$ Model Solitons
Kim, Y; Kim, Yoonbai; Moon, Sei-Hoon
1998-01-01
We study axially symmetric static solitons of O(3) nonlinear $\\sigma$ model coupled to (2+1)-dimensional anti-de Sitter gravity. The obtained solutions are not self-dual under static metric. The usual regular topological lump solution cannot form a black hole even though the scale of symmetry breaking is increased. There exist nontopological solitons of half integral winding in a given model, and the corresponding spacetimes involve charged Ba$\\tilde n$ados-Teitelboim-Zanelli black holes without non-Abelian scalar hair.
Chiral symmetry restoration in effective Lagrangian models
The restoration is studied of chiral symmetry in dense baryon matter using effective lagrangian models of QCD, in which baryons are described as topological solitons. Starting from the breaking of scale invariance and chiral symmetry in the QCD vacuum, the foundations are discussed of effective lagrangians and their relevance for applications to dense matter. Soliton models, such a the Skyrme model, show a phase transition at high densities, whose order parameter is the average scalar field. The properties are investigated of the two phases of the effective theory and show that the phase transition corresponds to the restoration of the chiral symmetry of QCD. It is argued that it should not be understood as deconfinement. The author then considers this phase transition in the context of the Cheshire Cat principle, which provides the link to the underlying quarks of QCD. An analogue of the Cheshire Cat property of this chiral bag model for baryons is found in solitons of effective lagrangians with a scalar glueball field. The Cheshire Cat interpretation of the results of effective lagrangians provides a consistent picture of chiral symmetry restoration at high densities. To verify this interpretation explicitly, the author finally generalizes the effective lagrangian approach to dense matter to a chiral bag model description with quark degrees of freedom
Soliton models are well-suited for dynamical calculations, such as hadron-hadron interactions and collisions, since for each variable in the Lagrangian the time derivative of that variable also appears. For such models, constrained (deformed) mean field solutions provide a basis for generator coordinate dynamical calculations. This requires the solution of a large number of coupled, nonlinear, differential equations involving the quark and scalar fields. The Henyey-Wilets method reduces the problem to the solution of a set of coupled, linear, inhomogeneous, differential equations to be iterated. In the chromodielectric model, color confinement is effected by the self and mutual interactios of the quarks through the chromelectric field. This requires the self-consistent calculation of the gluon propagator in a spatially varying dielectric function. This now involves the solution of a set of coupled, nonlinear integro-differential equations, which can be linearized and solved by iterations. The problem is computation intensive. 20 refs
Baryon resonances without quarks: A chiral soliton perspective
Karliner, M.
1987-03-01
In many processes involving low momentum transfer it is fruitful to regard the nucleon as a soliton or ''monopole-like'' configuration of the pion field. In particular, within this framework it is possible to obtain detailed predictions for pion-nucleon scattering amplitudes and for properties of baryon resonances. One can also derive model-independent linear relations between scattering amplitudes, such as ..pi..N and anti KN. A short survey of some recent results is given, including comparison with experimental data.
Soliton-soliton and wave-soliton collisions in Skyrme-like [sigma]-models
Kudryavtsev, A. (Dept. of Mathematical Sciences, Durham Univ. (United Kingdom)); Piette, B. (Dept. of Mathematical Sciences, Durham Univ. (United Kingdom)); Zakrzewski, W.J. (Dept. of Mathematical Sciences, Durham Univ. (United Kingdom))
1993-12-01
A skyrme-like inversion of the (2+1)-dimensional classical [sigma]-model is considered. Some aspects of soliton-soliton collisions are studied using both the numerical and phenomenological approaches. In particular, the problem of 90 scattering of solitons in the head-on collisions is analyzed. Properties of the two-soliton configurations for v[proportional to]v[sub cr] are discussed in terms of a specific solution, which may be called a 'disoliton'. This solution corresponds to a saddle point in the space of field configurations and is unstable with respect to the decay into two well separated solitons. Different classes of field configurations, which may be called 'one-dimensional' wave packets, are also studied as well as the interaction of these wave packets with a soliton. (orig.)
Carbone, Francesco; Dutykh, Denys; El, Gennady
2015-01-01
We undertake a detailed comparison of the results of direct numerical simulations of the integrable soliton gas dynamics with the analytical predictions inferred from the exact solutions of the relevant kinetic equation for solitons. We use the KdV soliton gas as a simplest analytically accessible model yielding major insight into the general properties of soliton gases in integrable systems. Two model problems are considered: (i) the propagation of a `trial' soliton through a one-component `...
Carbone, Francesco; El, Gennady
2015-01-01
We undertake a detailed comparison of the results of direct numerical simulations of the integrable soliton gas dynamics with the analytical predictions inferred from the exact solutions of the relevant kinetic equation for solitons. We use the KdV soliton gas as a simplest analytically accessible model yielding major insight into the general properties of soliton gases in integrable systems. Two model problems are considered: (i) the propagation of a `trial' soliton through a one-component `cold' soliton gas consisting of randomly distributed solitons of approximately the same amplitude; and (ii) collision of two cold soliton gases of different amplitudes (soliton gas shock tube problem) leading to the formation of an incoherend dispersive shock wave. In both cases excellent agreement is observed between the analytical predictions of the soliton gas kinetics and the direct numerical simulations. Our results confirm relevance of the kinetic equation for solitons as a quantitatively accurate model for macrosco...
Ledwig, Tim; Goeke, Klaus
2008-01-01
We investigate the vector transition form factors of the nucleon and vector meson $K^*$ to the pentaquark baryon $\\Theta^+$ within the framework of the SU(3) chiral quark-soliton model. We take into account the rotational $1/N_c$ and linear $m_{\\rm s}$ corrections, assuming isospin symmetry and employing the symmetry-conserving quantization. It turns out that the leading-order contributions to the form factors are almost cancelled by the rotational corrections. Because of this, the flavor SU(3) symmetry-breaking terms yield sizeable effects on the transition form factors. In particular, the main contribution to the electric transition form factor comes from the wave-function corrections, which is a consequence of the generalized Ademollo-Gatto theorem derived in the present work. We estimate with the help of the vector meson dominance the $K^*$ vector and tensor coupling constants for the $\\Theta^+$: $g_{K^{*}N\\Theta}=0.74 - 0.87$ and $f_{K^{*}N\\Theta}=0.53 - 1.16$. We argue that the outcome of the present wo...
Generalized simplicial chiral models
Using the auxiliary field representation of the simplicial chiral models on a (d-1)-dimensional simplex, the simplicial chiral models are generalized through replacing the term Tr(AA†) in the Lagrangian of these models by an arbitrary class function of AA†; V(AA†). This is the same method used in defining the generalized two-dimensional Yang-Mills theories (gYM2) from ordinary YM2. We call these models the 'generalized simplicial chiral models'. Using the results of the one-link integral over a U(N) matrix, the large-N saddle-point equations for eigenvalue density function ρ(z) in the weak (β>βc) and strong (βc) regions are computed. In d=2, where the model is in some sense related to the gYM2 theory, the saddle-point equations are solved for ρ(z) in the two regions, and the explicit value of critical point βc is calculated for V(B)=Tr Bn (B=AA†). For V(B)=Tr B2,Tr B3, and TrB4, the critical behaviour of the model at d=2 is studied, and by calculating the internal energy, it is shown that these models have a third order phase transition
Generalized simplicial chiral models
Alimohammadi, M
2000-01-01
Using the auxiliary field representation of the simplicial chiral models on a (d-1)-dimensional simplex, we generalize the simplicial chiral models by replacing the term Tr$(AA^{\\d})$ in the Lagrangian of these models, by an arbitrary class function of $AA^{\\d}; V(AA^{\\d})$. This is the same method that has been used in defining the generalized two-dimensional Yang-Mills theories (gYM_2) from ordinary YM_2. We call these models, the " generalized simplicial chiral models ". With the help of the results of one-link integral over a U(N) matrix, we compute the large-N saddle-point equations for eigenvalue density function $\\ro (z)$ in the weak ($\\b >\\b_c$) and strong ($\\b <\\b_c$) regions. In d=2, where the model somehow relates to gYM_2 theory, we solve the saddle-point equations and find $\\ro (z)$ in two region, and calculate the explicit value of critical point $\\b_c$ for $V(B)=TrB^n (B=AA^{\\d})$. For $V(B)=Tr B^2,Tr B^3$ and Tr$B^4$, we study the critical behaviour of the model at d=2, and by calculating t...
Inelastic soliton-soliton interaction in coninin models
The field equations with nonlinearity proportional to |PSI|sup(-α)PSI, α>0 (model 1 of Simonov-Tjon) are solved in one spatial dimension with initial conditions corresponding to two colliding solitons. One or several breathers are generated during the collision process and the solitons remain stable after collision. An extensive study is done of the collision process and the breather generation for different values of the interaction parameter α, velocities and relative phase in the initial state. In addition the collision of two breathers is considered. Some comparative study of one dimensional model of the Werle type is also done
Baryons with Two Heavy Quarks as Solitons
Bander, Myron; Subbaraman, Anand
1994-01-01
Using the chiral soliton model and heavy quark symmetry we study baryons containing two heavy quarks. If there exists a stable (under strong interactions) meson consisting of two heavy quarks and two light ones, then we find that there always exists a state of this meson bound to a chiral soliton and to a chiral anti-soliton, corresponding to a two heavy quark baryon and a baryon containing two heavy anti-quarks and five light quarks, or a ``heptaquark".
Scattering in Soliton Models and the Bosonic Exchange description
Coriano, Claudio; Parwani, Rajesh R.; YAMAGISHI, HIDENAGA; Zahed, Ismail
1992-01-01
We argue that the description of meson-nucleon dynamics based on the boson-exchange approach, is compatible with the description of the nucleon as a soliton in the nonrelativistic limit. Our arguments are based on an analysis of the meson-soliton form factor and the exact meson-soliton and soliton-soliton scattering amplitudes in the Sine-Gordon model.
Hopf solitons in the AFZ model
The Aratyn–Ferreira–Zimerman (AFZ) model is a conformal field theory in three-dimensional space. It has solutions that are topological solitons classified by an integer-valued Hopf index. There exist infinitely many axial solutions which have been found analytically. Static axial, knot and linked solitons are found numerically using a modified volume preserving flow for Hopf index one to eight, allowing for comparison with other Hopf soliton models. Solutions include a static trefoil knot at Hopf index five. A one-parameter family of conformal Skyrme–Faddeev models, consisting of linear combinations of the Nicole and AFZ models, are also investigated numerically. The transition of solutions for Hopf index four is mapped across these models. A topological change between linked and axial solutions occurs, with fewer models (or a limited range of parameter values) permitting axial solitons than linked solitons at Hopf index four
Heavy Quark Solitons in the Nambu--Jona-Lasinio Model
Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.); Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Z{ü}ckert, U.; Reinhardt, H.
1995-01-01
The Nambu--Jona-Lasinio model (NJL) is extended to incorporate heavy quark spin-symmetry. In this model baryons containing one heavy quark are analyzed as bound-states of light baryons, represented as chiral solitons, and mesons containing one heavy quark. From related studies in Skyrme type models, the ground-state heavy baryon is known to arise for the heavy meson in a P--wave configuration. In the limit of an infinitely large quark mass the heavy meson wave-function is sharply peaked at th...
Soliton solutions of Chiral Born-Infeld Theory and baryons
Pavlovsky, Oleg V.
2003-01-01
Finite-energy topological spherically symmetrical solutions of Chiral Born-Infeld Theory are studied. Properties of these solution are obtained, and a possible physical interpretation is also given. We compute static properties of baryons (mass,main radius, magnetic main radius, axial coupling constant) whose solutions can be interpreted as the baryons of QCD.
Dirac brackets for the chiral Schwinger model with chiral constraint
Dirac brackets for the chiral Schwinger model with chiral constraint are derived perturbatively from the correlation function by the BJL limit method. The results show that the Poissons brackets are not consistent in this theory. (author)
Stationary dissipative solitons of Model G
Pulver, Matthew; LaViolette, Paul A.
2013-07-01
Model G, the earliest reaction-diffusion system proposed to support the existence of solitons is shown to do so under distant steady-state boundary conditions. Subatomic particle physics phenomenology, including multi-particle bonding, movement in concentration gradients, and a particle structure matching Kelly's charge distribution model of the nucleon, are observed. Lastly, it is shown how a three-variable reversible Brusselator, a close relative of Model G, can also support solitons.
Solitonic objects play a central role in gauge and string theory (as, e.g., monopoles, black holes, D-branes, etc.). Certain string backgrounds produce a noncommutative deformation of the low-energy effective field theory, which allows for new types of solitonic solutions. I present the construction, moduli spaces and dynamics of Moyal-deformed solitons, exemplified in the 2+1 dimensional Yang-Mills-Higgs theory and its Bogomolny system, which is gauge-fixed to an integrable chiral sigma model (the Ward model). Noncommutative solitons for various 1+1 dimensional integrable systems (such as sine-Gordon) easily follow by dimensional and algebraic reduction. Supersymmetric extensions exist as well and are related to twistor string theory
Solitons in the one-dimensional forest fire model
Bak, Per; Chen, Kan; Paczuski, Maya
2000-01-01
Fires in the one-dimensional Bak-Chen-Tang forest fire model propagate as solitons, resembling shocks in Burgers turbulence. The branching of solitons, creating new fires, is balanced by the pair-wise annihilation of oppositely moving solitons. Two distinct, diverging length scales appear in the limit where the growth rate of trees, $p$, vanishes. The width of the solitons, $w$, diverges as a power law, $1/p$, while the average distance between solitons diverges much faster as $ d \\sim \\exp({...
Soliton models for thick branes
Peyravi, Marzieh; Riazi, Nematollah; Lobo, Francisco S. N.
2016-05-01
In this work, we present new soliton solutions for thick branes in 4+1 dimensions. In particular, we consider brane models based on the sine-Gordon (SG), φ 4 and φ 6 scalar fields, which have broken Z2 symmetry in some cases and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacua. These vacua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighborhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the w^2 term in the expansion of the potential for the resulting Schrödinger-like equation, where w is the five-dimensional coordinate. It turns out that the φ ^4 brane is stable, while there are unstable modes for certain ranges of the model parameters in the SG and φ ^6 branes.
Soliton models for thick branes
Peyravi, Marzieh; Lobo, Francisco S N
2015-01-01
In this work, we present new soliton solutions for thick branes in $4+1$ dimensions. In particular, we consider brane models based on the sine-Gordon ($SG$), $\\varphi^{4}$ and $\\varphi^{6}$ scalar fields, which have broken $Z_{2}$ symmetry in some cases, and are responsible for supporting and stabilizing the thick branes. The origin of the symmetry breaking in these models resides in the fact that the modified scalar field potential may have non-degenerate vacuua. These vacuua determine the cosmological constant on both sides of the brane. We also study the geodesic equations along the fifth dimension, in order to explore the particle motion in the neighbourhood of the brane. Furthermore, we examine the stability of the thick branes, by determining the sign of the $w^2$ term in the expansion of the potential for the resulting Schrodinger-like equation, where $w$ is the 5-dimensional coordinate. It turns out that the $\\phi^4$ brane is stable, while there are unstable modes for certain ranges of the model param...
Rahaman, Anisur
2015-01-01
The vector type of interaction of the Thirring-Wess model was replaced by the chiral type and a new model was presented which was termed as chiral Thirring-Wess model in \\cite{THAR}. The model was studied there with a Faddeevian class of regularization that contained few ambiguity parameters with the apprehension that unitarity might be threatened like the chiral generation of the Schwinger model. In the present work it has been shown that no counter term containing the regularization ambiguity is needed for this model to be physically sensible. So the chiral Thirring-Wess model is studied here without the presence of any ambiguity parameter and it has been found that the model not only remain exactly solvable but also does not loose the unitarity like the chiral generation of the Schwinger model. The phase space structure and the theoretical spectrum of this new model has been determined in the present scenario through Dirac's method of quantization of constraint system. The theoretical spectrum is found to ...
The stability of the classical Skyrme model SU(2) hedgehog soliton
It is presented the exact power series solution at the origin for the classical SU(2) Skyrme model lagrangean with a hedgehog ansatz. The analogous solution at infinity is also considered, and the dependence of the chiral angle on two dimensionless variable is exhibited (a consequence of having two completely arbitrary parameters). The classical Skyrme model soliton turns out to be as unstable as the pure non-linear sigmahe Skyrme parameter is fixed, breaking the scale invariance on both variables, the mass of the soliton has a stable minimum. (author)
Solitonic axion condensates modeling dark matter halos
Castañeda Valle, David, E-mail: casvada@gmail.com; Mielke, Eckehard W., E-mail: ekke@xanum.uam.mx
2013-09-15
Instead of fluid type dark matter (DM), axion-like scalar fields with a periodic self-interaction or some truncations of it are analyzed as a model of galaxy halos. It is probed if such cold Bose–Einstein type condensates could provide a viable soliton type interpretation of the DM ‘bullets’ observed by means of gravitational lensing in merging galaxy clusters. We study solitary waves for two self-interacting potentials in the relativistic Klein–Gordon equation, mainly in lower dimensions, and visualize the approximately shape-invariant collisions of two ‘lump’ type solitons. -- Highlights: •An axion model of dark matter is considered. •Collision of axion type solitons are studied in a two dimensional toy model. •Relations to dark matter collisions in galaxy clusters are proposed.
Cranking the chiral soliton bag model
Clement, G.; Stern, J.
1988-10-01
The generation of physical states from mean field hedgehogs by cranking is extended to coherent hedgehogs, thus improving the agreement between the cranking and coherent state projection methods, and enabling us to correct simultaneously for translational and rotational fluctuations. These corrections lead to a drastic reduction in the mean nucleon-delta mass which, for the physical values of m/sub ..pi../ and F/sub ..pi../, is lower than, or approximately equal to, the experimental value.
Model with solitons in (2+1) dimensions
Izquierdo, J.M.; Rashid, M.S.; Piette, B.; Zakrzewski, W.J. (Durham Univ. (United Kingdom). Dept. of Mathematics)
1992-01-01
We consider various models in (2+1) dimensions which possess soliton-like solutions. We discuss the additional terms that must be added to the conventional S{sup 2} model in order that its solutions are stable and so can be treated as solitons. The role of various terms is analysed and some properties of the solitonic solutions are discussed. (orig.).
Solitonic axion condensates modeling dark matter halos
Castañeda Valle, David; Mielke, Eckehard W.
2013-09-01
Instead of fluid type dark matter (DM), axion-like scalar fields with a periodic self-interaction or some truncations of it are analyzed as a model of galaxy halos. It is probed if such cold Bose-Einstein type condensates could provide a viable soliton type interpretation of the DM 'bullets' observed by means of gravitational lensing in merging galaxy clusters. We study solitary waves for two self-interacting potentials in the relativistic Klein-Gordon equation, mainly in lower dimensions, and visualize the approximately shape-invariant collisions of two 'lump' type solitons.
Solutions of ward's modified chiral model
We discuss the adaptation of Uhlenbeck's method of solving the chiral model in 2 Euclidean dimensions to Ward's modified chiral model in (2+1) dimensions. We show that the method reduces the problem of solving the second-order partial differential equations for the chiral field to solving a sequence of first-order partial differential equations for time dependent projector valued fields
Nucleon electric polarizability in soliton models and the role of the seagull terms
Scoccola, Norberto N.; Cohen, Thomas D.
1995-01-01
The full Hamiltonian of the soliton models contains no electric seagull terms. Here it is shown that if one restricts the fields to the collective subspace then electric seagull terms are induced in the effective Hamiltonian. These effective seagull contributions are consistent with gauge invariance. They also reproduce the leading nonanalytic behavior of a large $N_c$ chiral perturbation theory calculation of the electric polarizability.
Chiral Cosmological Models: Dark Sector Fields Description
Chervon, S V
2014-01-01
The present review is devoted to a Chiral Cosmological Model as the self-gravitating nonlinear sigma model with the potential of (self)interactions employed in cosmology. The chiral cosmological model has successive applications in descriptions of the inflationary epoch of the Universe evolution; the present accelerated expansion of the Universe also can be described by the chiral fields multiplet as the dark energy in wide sense. To be more illustrative we are often addressed to the two-component chiral cosmological model. Namely, the two-component chiral cosmological model describing the phantom field with interaction to a canonical scalar field is analyzed in details. New generalized model of quintom character is proposed and exact solutions are founded out. In the review we represented the perturbation theory for chiral cosmological model with the aim to describe the structure formation using the progress achieved in the inflation theory. It was shown that cosmological perturbations from chiral fields can...
Chiral magnetic effect in the PNJL model
Fukushima, Kenji; Gatto, Raoul
2010-01-01
We study the two-flavor Nambu--Jona-Lasinio model with the Polyakov loop (PNJL model) in the presence of a strong magnetic field and a chiral chemical potential $\\mu_5$ which mimics the effect of imbalanced chirality due to QCD instanton and/or sphaleron transitions. Firstly we focus on the properties of chiral symmetry breaking and deconfinement crossover under the strong magnetic field. Then we discuss the role of $\\mu_5$ on the phase structure. Finally the chirality charge, electric current, and their susceptibility, which are relevant to the Chiral Magnetic Effect, are computed in the model.
Non-topological soliton bag model
The Friedberg-Lee soliton model, which effects confinement by a quantal scalar field, is discussed. The Lagrangian for the non-topological soliton model is the usual QCD Lagrangian supplemented by a non-linear scalar sigma field term. Static solutions to the field equations are considered in the mean field approximation. Small amplitude oscillations are discussed. Quantum alternatives to the mean field approximation are also considered. Methods of momentum projection and Lorentz boost are described, and the generator coordinate method is discussed. Calculations of the N-N interaction are reviewed briefly. Also discussed is one-gluon exchange, as well as the pion and dressing of the baryons. The hadron states are summarized. One loop quantum corrections are discussed briefly. Work in progress is mentioned in the areas of N-anti N annihilation, the many bag problem, and a Pauli equation for the nucleon. 31 refs
Non-topological soliton bag model
Wilets, L.
1986-01-01
The Friedberg-Lee soliton model, which effects confinement by a quantal scalar field, is discussed. The Lagrangian for the non-topological soliton model is the usual QCD Lagrangian supplemented by a non-linear scalar sigma field term. Static solutions to the field equations are considered in the mean field approximation. Small amplitude oscillations are discussed. Quantum alternatives to the mean field approximation are also considered. Methods of momentum projection and Lorentz boost are described, and the generator coordinate method is discussed. Calculations of the N-N interaction are reviewed briefly. Also discussed is one-gluon exchange, as well as the pion and dressing of the baryons. The hadron states are summarized. One loop quantum corrections are discussed briefly. Work in progress is mentioned in the areas of N-anti N annihilation, the many bag problem, and a Pauli equation for the nucleon. 31 refs. (LEW)
Topological solitons in the supersymmetric Skyrme model
Gudnason, Sven Bjarke; Sasaki, Shin
2016-01-01
A supersymmetric extension of the Skyrme model was obtained recently, which consists of only the Skyrme term in the Nambu-Goldstone (pion) sector complemented by the same number of quasi-Nambu-Goldstone bosons. Scherk-Schwarz dimensional reduction yields a kinetic term in three or lower dimensions and a potential term in two dimensions, preserving supersymmetry. Euclidean solitons (instantons) are constructed in the supersymmetric Skyrme model. In four dimensions, the soliton is an instanton first found by Speight. Scherk-Schwarz dimensional reduction is then performed once to get a 3-dimensional theory in which a 3d Skyrmion-instanton is found and then once more to get a 2d theory in which a 2d vortex-instanton is obtained. Although the last one is a global vortex it has finite action in contrast to conventional theory. All of them are non-BPS states breaking all supersymmetries.
Yanagisawa, Takashi
2016-02-01
We investigate the chiral sine-Gordon model using the renormalization group method. The chiral sine-Gordon model is a model for G-valued fields and describes a new class of phase transitions, where G is a compact Lie group. We show that the model is renormalizable by means of a perturbation expansion and we derive beta functions of the renormalization group theory. The coefficients of beta functions are represented by the Casimir invariants. The model contains both asymptotically free and ultraviolet strong-coupling regions. The beta functions have a zero which is a bifurcation point that divides the parameter space into two regions; they are the weak-coupling region and the strong-coupling region. A large-N model is also considered. This model is reduced to the conventional sine-Gordon model that describes the Kosterlitz-Thouless transition near the fixed point. In the strong-coupling limit, the model is reduced to a U(N) matrix model.
Yanagisawa, Takashi
2016-01-01
We investigate the chiral sine-Gordon model using the renormalization group method. The chiral sine-Gordon model is a model for $G$-valued fields and describes a new class of phase transitions, where $G$ is a compact Lie group. We show that the model is renormalizable by means of a perturbation expansion and we derive beta functions of the renormalization group theory. The coefficients of beta functions are represented by the Casimir invariants. The model contains both asymptotically free and ultraviolet strong coupling regions. The beta functions have a zero which is a bifurcation point that divides the parameter space into two regions; they are the weak coupling region and the strong coupling region. A large-$N$ model is also considered. This model is reduced to the conventional sine-Gordon model that describes the Kosterlitz-Thouless transition near the fixed point. In the strong-coupling limit, the model is reduced to a $U(N)$ matrix model.
Principal chiral model on superspheres
We investigate the spectrum of the principal chiral model (PCM) on odd-dimensional superspheres as a function of the curvature radius R. For volume-filling branes on S3verticalstroke2, we compute the exact boundary spectrum as a function of R. The extension to higher dimensional superspheres is discussed, but not carried out in detail. Our results provide very convincing evidence in favor of the strong-weak coupling duality between supersphere PCMs and OSP(2S+2 vertical stroke 2S) Gross-Neveu models that was recently conjectured by Candu and Saleur. (orig.)
Principal chiral model on superspheres
Mitev, V.; Schomerus, V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Quella, T. [Amsterdam Univ. (Netherlands). Inst. for Theoretical Physics
2008-09-15
We investigate the spectrum of the principal chiral model (PCM) on odd-dimensional superspheres as a function of the curvature radius R. For volume-filling branes on S{sup 3} {sup vertical} {sup stroke} {sup 2}, we compute the exact boundary spectrum as a function of R. The extension to higher dimensional superspheres is discussed, but not carried out in detail. Our results provide very convincing evidence in favor of the strong-weak coupling duality between supersphere PCMs and OSP(2S+2 vertical stroke 2S) Gross-Neveu models that was recently conjectured by Candu and Saleur. (orig.)
A Statistical Model for Soliton Particle Interaction in Plasmas
Dysthe, K. B.; Pécseli, Hans; Truelsen, J.
1986-01-01
A statistical model for soliton-particle interaction is presented. A master equation is derived for the time evolution of the particle velocity distribution as induced by resonant interaction with Korteweg-de Vries solitons. The detailed energy balance during the interaction subsequently determines...... the evolution of the soliton amplitude distribution. The analysis applies equally well for weakly nonlinear plasma waves in a strongly magnetized waveguide, or for ion acoustic waves propagating in one-dimensional systems....
Chiral dynamics of baryons in the perturbative chiral quark model
Pumsa-ard, K.
2006-07-01
In this work we develop and apply variants of a perturbative chiral quark model (PCQM) to the study of baryonic properties dominantly in the low-energy region. In a first step we consider a noncovariant form of the PCQM, where confinement is modelled by a static, effective potential and chiral corrections are treated to second order, in line with similar chiral quark models. We apply the PCQM to the study of the electromagnetic form factors of the baryon octet. We focus in particular on the low-energy observables such as the magnetic moments, the charge and magnetic radii. In addition, the electromagnetic N-delta transition is also studied in the framework of the PCQM. In the chiral loop calculations we consider a quark propagator, which is restricted to the quark ground state, or in hadronic language to nucleon and delta intermediate states, for simplicity. We furthermore include the low-lying excited states to the quark propagator. In particular, the charge radius of the neutron and the transverse helicity amplitudes of the N-delta transition are considerably improved by this additional effect. In a next step we develop a manifestly Lorentz covariant version of the PCQM, where in addition higher order chiral corrections are included. The full chiral quark Lagrangian is motivated by and in analogy to the one of Chiral Perturbation Theory (ChPT). This Lagrangian contains a set of low energy constants (LECs), which are parameters encoding short distance effects and heavy degrees of freedom. We evaluate the chiral Lagrangian to order O(p{sup 4}) and to one loop to generate the dressing of the bare quark operators by pseudoscalar mesons. In addition we include the vector meson degrees of freedom in our study. Projection of the dressed quark operators on the baryonic level serves to calculate the relevant matrix elements. In a first application of this scheme, we resort to a parameterization of the valence quark form factors in the electromagnetic sector. Constraints
Soliton model of a photon propagating in dielectrics
Bersons, I.; Veilande, R.; Balcers, O.
2016-06-01
The previously proposed three-dimensional soliton model of a photon propagating in vacuum is modified to describe its propagation in a homogeneous linear dielectric medium. The one-soliton solution of the derived nonlinear equation correctly predicts the energy and the Abraham and Minkowski momenta of the photon in dielectrics. A new nonlinear equation is proposed, which has a one-soliton solution that at every point oscillates with the same frequency and falls exponentially in the longitudinal, as well as in the transverse direction from the centre of the soliton.
Solitons are mathematical objects which arise as solutions of certain non-linear dispersive wave equations like the Korteweg-de Vries (KdV), the non-linear Schroedinger (NLS) and the self-induced transparency (SIT) and sine-Gordon (s-G) equations. These govern, respectively, ion acoustic waves in plasmas, the self-steepening of optical pulses and the formation of optical filaments by intense laser light, and the propagation of approximately -9s optical pulses in resonant media, for example. The equations and applications are very different, yet solitons have many features in common: they collide like particles and, for example, the break-up of coherent 10-9s optical pulses of 'area' 6π into three 2π pulses is a break-up into three solitons. The KdV, NLS and s-G equations are introduced and some single and multi-soliton solutions displayed. As one example of an application in non-linear physics the KdV equation is derived in detail for ion acoustic waves. Next the relevance of the KdV to recurrence phenomena in non-linear lattices (the Fermi-Pasta-Ulam problem) is noted. The theory of SIT in non-degenerate media is developed and used as a physical example of the s-G equation. A double s-G is then derived for SIT in degenerate media. It is shown that soliton-like behaviour is now established by 'wobbling' 4π pulses. SIT for the 2Ssub(1/2)(F=2)→2Psub(1/2)(F=1,2)D1 transitions in sodium vapour is treated. Applications of solitons to Josephson junctions, to optical filaments and to other non-linear physics (plasmas, lattices, particle physics) are briefly sketched. (author)
Role of structural factors in formation of chiral magnetic soliton lattice in Cr1/3NbS2
The sign and strength of magnetic interactions not only between nearest neighbors, but also for longer-range neighbors in the Cr1/3NbS2 intercalation compound have been calculated on the basis of structural data. It has been found that left-handed spin helices in Cr1/3NbS2 are formed from strength-dominant at low temperatures antiferromagnetic (AFM) interactions between triangular planes of Cr3+ ions through the plane of just one of two crystallographically equivalent diagonals of side faces of embedded into each other trigonal prisms building up the crystal lattice of magnetic Cr3+ ions. These helices are oriented along the c axis and packed into two-dimensional triangular lattices in planes perpendicular to these helices directions and lay one upon each other with a displacement. The competition of the above AFM helices with weaker inter-helix AFM interactions could promote the emergence of a long-period helical spin structure. One can assume that in this case, the role of Dzyaloshinskii-Moriya interaction consists of final ordering and stabilization of chiral spin helices into a chiral magnetic soliton lattice. The possibility of emergence of solitons in M1/3NbX2 and M1/3TaX2 (M = Cr, V, Ti, Rh, Ni, Co, Fe, and Mn; X = S and Se) intercalate compounds has been examined. Two important factors caused by the crystal structure (predominant chiral magnetic helices and their competition with weaker inter-helix interactions not destructing the system quasi-one-dimensional character) can be used for the crystal chemistry search of solitons.
Tho, N V; Tho, Nguyen Vien; Hoa, Phu Chi
2000-01-01
The chiral symmetry-breaking term of the Skyrme model with massive pion is modified to obtain the hedgehog profile function which is in best coincidence with the kink-like profile function. For the modified Lagrangian, the minimum of the energy of the B=2 twisty skyrmion configuration is lower than the values for both the cases of the Skyrme Lagrangian with and without the non-modified symmetry-breaking term. The equations of motion for the time-dependent hedgehog of this model and for a generalizated Skyrme model including sixth-order stabilizing term are derived and integrated nummerically. The time evolution of soliton is obtained. We have observed the seft-exitation of soliton because of the fast developement of fluctuation.
Solitonic field configurations of the Nambu-Jona-Lasinio model in the medium
In this thesis the properties of a SU(2) NJL soliton were studied, which is embedded in a gas consisting of constituent quarks with a self-consistently determined constituent quark mass. It serves as model for a nucleon surrounded by hadronic matter and yields statements on the properties of the nucleon in dependence on temperature and density of the surrounding matter. The four-quark point interaction of the NJL model is treated in the mean-field approximation constrained to hedgehog configurations and chiral circles
Chiral Schwinger model at finite temperature
We discuss the chiral Schwinger model at finite temperature using Fujikawa's method. We solve this model exactly and show that the axial anomaly and the dynamically generated mass for the gauge field are temperature independent. (author). 20 refs
Ising models and soliton equations
Several new results for the critical point of correlation functions of the Hirota equation are derived within the two-dimensional Ising model. The recent success of the conformal-invariance approach in the determination of a critical two-spin correration function is analyzed. The two-spin correlation function is predicted to be rotationally invariant and to decay with a power law in this approach. In the approach suggested here systematic corrections due to the underlying lattice breaking the rotational invariance are obtained
Solitons in spiraling systems: a continuum model for dynamical phyllotaxis
Nisoli, Cristiano [Los Alamos National Laboratory
2009-01-01
A novel, protean, topological soliton has been shown to emerge in systems of repulsive particles in cylindrical geometries, whose statics is described by the number-theoretical objects of Phyllotaxis. We present a minimal and local continuum model that can explain many of the features of the phyllotactic soliton, such as speed, screw shift, energy transport and, for Wigner crystal on a nanotube, charge. The treatment applies just as well in general to solitons in spiraling systems. Unlike e.g. Sine-Gornon-like solitons, our soliton can exist between non degenerate structure, implies a power flow through the system, dynamics of the domains it separates, and possesses pulses, both static and dynamic. Its applications include from charge transfer in Wigner Crystals on nanotubes or A to B-DNA transitions.
Chiral Lagrangian and chiral quark model from confinement in QCD
Simonov, Yu A
2015-01-01
The effective chiral Lagrangian in both nonlocal form $L_{ECCL}$ and standard local form $L_{ECL}$ are derived in QCD using the confining kernel, obtained in the vacuum correlator formalism. As a result all coefficients of $L_{ECL}$ can be computed via $q\\bar q$ Green's functions. In the $p^2$ order of $L_{ECL}$ one obtains GOR relations and quark decay constants $f_a$ are calculated $a=1,...8$, while in the $p^4$ order the coefficients $L_1, L_2, L_3,L_4, L_5, L_6$ are obtained in good agreement with the values given by data. The chiral quark model is shown to be a simple consequence of $L_{ECCL}$ with defined coefficients. It is demonstrated that $L_{ECCL}$ gives an extension of the limiting low-energy Lagrangian $L_{ECL}$ to arbitrary momenta.
The theta^+ baryon in soliton models: large Nc QCD and the validity of rigid-rotor quantization
Cohen, Thomas D.
2003-01-01
A light collective theta+ baryon state (with strangeness +1) was predicted via rigid-rotor collective quantization of SU(3) chiral soliton models. This paper explores the validity of this treatment. A number of rather general analyses suggest that predictions of exotic baryon properties based on this approximation do not follow from large Nc QCD. These include an analysis of the baryon's width, a comparison of the predictions with general large Nc consistency conditions of the Gervais-Sakita-...
Soliton models in resonant and nonresonant optical ﬁbers
K Porsezian
2001-11-01
In this review, considering the important linear and nonlinear optical effects like group velocity dispersion, higher order dispersion, Kerr nonlinearity, self-steepening, stimulated Raman scattering, birefringence, self-induced transparency and various inhomogeneous effects in ﬁbers, the completely integrable concept and bright, dark and self-induced transparency soliton models in nonlinear ﬁber optics are discussed. Considering the above important optical effects, the different completely integrable soliton models in the form of nonlinear Schrödinger (NLS), NLS-MaxwellBloch (MB) type equations reported in the literature are discussed. Finally, solitons in stimulated Raman scattering (SRS) system is brieﬂy discussed.
Can plane wave modes be physical modes in soliton models?
Aldabe, F
1995-01-01
I show that plane waves may not be used as asymptotic states in soliton models because they describe unphysical states. When asymptotic states are taken to be physical there is no T-matrix of \\cO(1).
Effective action in general chiral superfield model
Petrov, A. Yu.
2000-01-01
The effective action in general chiral superfield model with arbitrary k\\"{a}hlerian potential $K(\\bar{\\Phi},\\Phi)$ and chiral (holomorphic) potential $W(\\Phi)$ is considered. The one-loop and two-loop contributions to k\\"{a}hlerian effective potential and two-loop (first non-zero) contribution to chiral effective potential are found for arbitrary form of functions $K(\\bar{\\Phi},\\Phi)$ and $W(\\Phi)$. It is found that despite the theory is non-renormalizable in general case two-loop contributi...
Salerno, Mario; Rodríguez Quintero, Niurka
2002-01-01
The mechanism underlying the soliton ratchet, both in absence and in presence of noise, is investigated. We show the existence of an asymmetric internal mode on the soliton profile that couples, through the damping in the system, to the soliton translational mode. Effective soliton transport is achieved when the internal mode and the external force are phase locked. We use as a working model a generalized double sine-Gordon equation. The phenomenon is expected to be valid for generic soliton ...
Parity doublers in chiral potential quark models
The effect of spontaneous breaking of chiral symmetry over the spectrum of highly excited hadrons is addressed in the framework of a microscopic chiral potential quark model (Generalised Nambu-Jona-Lasinio model) with a vectorial instantaneous quark kernel of a generic form. A heavy-light quark-antiquark bound system is considered, as an example, and the Lorentz nature of the effective light-quark potential is identified to be a pure Lorentz-scalar, for low-lying states in the spectrum, and to become a pure spatial Lorentz vector, for highly excited states. Consequently, the splitting between the partners in chiral doublets is demonstrated to decrease fast in the upper part of the spectrum so that neighboring states of an opposite parity become almost degenerate. A detailed microscopic picture of such a 'chiral symmetry restoration' in the spectrum of highly excited hadrons is drawn and the corresponding scale of restoration is estimated
Chiral effective model with the Polyakov loop
Fukushima, Kenji
2003-01-01
We discuss how the simultaneous crossovers of deconfinement and chiral restoration can be realized. We propose a dynamical mechanism assuming that the effective potential gives a finite value of the chiral condensate if the Polyakov loop vanishes. Using a simple model, we demonstrate that our idea works well for small quark mass, though there should be further constraints to reach the perfect locking of two phenomena.
Hernandez Tenorio, C.; Villagran Vargas, E.; Serkin, Vladimir N.; Aguero Granados, M.; Belyaeva, T. L.; Pena Moreno, R.; Morales Lara, L.
2005-09-01
The dynamics of nonlinear solitary waves is studied by using the model of nonlinear Schrödinger equation (NSE) with an external harmonic potential. The model allows one to analyse on the general basis a variety of nonlinear phenomena appearing both in a Bose—Einstein condensate in a magnetic trap, whose profile is described by a quadratic function of coordinates, and in nonlinear optics, physics of lasers, and biophysics. It is shown that exact solutions for a quantum-mechanical particle in a harmonic potential and solutions obtained within the framework of the adiabatic perturbation theory for bright solitons in a parabolic trap are completely identical. This fact not only proves once more that solitons behave like particles but also that they can preserve such properties in different traps for which the parabolic approximation is valid near potential energy minima. The conditions are found for formation of stable stationary states of antiphase solitons in a harmonic potential. The interaction dynamics of solitons in nonstationary potentials is studied and the possibility of the appearance of a soliton parametric resonance at which the amplitude of soliton oscillations in a trap exponentially increases with time is shown. It is shown that exact solutions of the problem found using the Miura transformation open up the possibility to control the dynamics of solitons. New effects are predicted, which are called the reversible and irreversible denaturation of solitons in a nonstationary harmonic potential.
Young's experiment scheme modification for a possible observation of "soliton" interference model
Ekomasov, E. G.; Salimov, R. K.
2015-01-01
We consider the "soliton" interference model that complements the usual wave and corpuscular models of two-slit interference. The scheme of the experiment to verify such "soliton" interference model has been suggested.
Hernandez Tenorio, C.; Villagran Vargas, E.; Serkin, Vladimir N.; Aguero Granados, M.; Belyaeva, T. L.; Pena Moreno, R.; Morales Lara, L.
2005-10-01
The dynamics of dark solitons is studied within the framework of the mathematical model of nonlinear Schrödinger equation (NSE) with an external harmonic potential. A comparative analysis of the solutions of nonstationary problems is performed for a linear harmonic oscillator and the NSE model with a harmonic potential for different signs of the self-action potential. It is shown that the main specific feature of the dynamics of dark NSE solitons in a parabolic trap is the formation of solitons with dynamically changing form factors producing the periodic variation in the modulation depth (the degree of 'blackness') of dark solitons. The oscillation period of the dark soliton does not coincide with the oscillation period of a linear quantum-mechanical oscillator, which is caused by the periodic transformation of the black soliton to the grey one and vice versa. The conditions of applicability of the method of inverse scattering problem are presented, the generalised Lax pair is found, and exact soliton solutions are given for the mathematical NSE model with an external harmonic potential.
Two chiral nonet model with massless quarks
Fariborz, Amir H; Schechter, Joseph
2007-01-01
We present a detailed study of a linear sigma model containing one chiral nonet transforming under U(1)$_A$ as a quark-antiquark composite and another chiral nonet transforming as a diquark-anti diquark composite (or, equivalently from a symmetry point of view, as a two meson molecule). The model provides an intuitive explanation of a current puzzle in low energy QCD: Recent work has suggested the existence of a lighter than 1 GeV nonet of scalar mesons which behave like four quark composites. On the other hand, the validity of a spontaneously broken chiral symmetric description would suggest that these states be chiral partners of the light pseudoscalar mesons, which are two quark composites. The model solves the problem by starting with the two chiral nonets mentioned and allowing them to mix with each other. The input of physical masses in the SU(3) invariant limit for two scalar octets and an "excited" pion octet results in a mixing pattern wherein the light scalars have a large four quark content while t...
Two chiral nonet model with massless quarks
We present a detailed study of a linear sigma model containing one chiral nonet transforming under U(1)A as a quark-antiquark composite and another chiral nonet transforming as a diquark-antidiquark composite (or, equivalently from a symmetry point of view, as a two meson molecule). The model provides an intuitive explanation of a current puzzle in low energy QCD: Recent work has suggested the existence of a lighter than 1 GeV nonet of scalar mesons which behave like four quark composites. On the other hand, the validity of a spontaneously broken chiral symmetric description would suggest that these states be chiral partners of the light pseudoscalar mesons, which are two quark composites. The model solves the problem by starting with the two chiral nonets mentioned and allowing them to mix with each other. The input of physical masses in the SU(3) invariant limit for two scalar octets and an excited pion octet results in a mixing pattern wherein the light scalars have a large four quark content while the light pseudoscalars have a large two quark content. One light isosinglet scalar is exceptionally light. In addition, the pion pion scattering is also studied and the current algebra theorem is verified for massless pions which contain some four quark admixture
Chiral symmetry breaking in brane models
We discuss the chiral symmetry breaking in general intersecting Dq/Dp brane models consisting of Nc Dq-branes and a single Dp-brane with an s-dimensional intersection. There exists a QCD-like theory localized at the intersection and the Dq/Dp model gives a holographic description of it. The rotational symmetry of directions transverse to both of the Dq and Dp-branes can be identified with a chiral symmetry, which is non-Abelian for certain cases. The asymptotic distance between the Dq-branes and the Dp-brane corresponds to a quark mass. By studying the probe Dp-brane dynamics in a Dq-brane background in the near horizon and large Nc limit we find that the chiral symmetry is spontaneously broken and there appear (pseudo-)Nambu-Goldstone bosons. We also discuss the models at finite temperature
Pentaquarks in chiral color dielectric model
S C Pathak
2006-04-01
Recent experiments indicate that a narrow baryonic state having strangeness +1 and mass of about 1540 MeV may be existing. Such a state was predicted in chiral model by Diakonov et al. In this work I compute the mass and width of this state in chiral color dielectric model. I show that the computed width is about 30 MeV. I find that the mass of the state can be fitted to the experimentally observed mass by invoking a color neutral vector field and its interaction with the quarks.
Ioannidou, Theodora; Zakrzewski, Wojtek
1998-01-01
A one parameter generalization of Ward's chiral model in 2+1 dimensions is given. Like the original model the present one is integrable and possesses a positive-definite and conserved energy and $y$-momentum. The details of the scattering depend on the value of the parameter of the generalisation.
Studies on phenomenological hadron models with chiral symmetry
In this report we consider, in the context of phenomenological models for hadrons, several aspects of Skyrme-type and hybrid bag models. In the first of the two central parts we discuss two qualitatively different generalizations of the minimal SU(2) Skyrme model. One of these consists in adding to the Lagrangian density a symmetric term of fourth order in the field derivatives. Its consequences are determined for solutions and observables by analytical and numerical investigations. In the other we propose a contribution for explicit isospin symmetry breaking in the mesonic as well as the baryonic sector. Together with the standard nonlinear σ-model term it allows for exact time-dependent classical soliton solutions. Their quantization leads to a quantitative connection between the hadronic isospin mass differenced of pions and nucleons. The second main part of this report is devoted to the generalization of SU(2) bag models under the aspect of chiral symmetry. We first show that the construction of appropriate surface terms in the Lagrangian density necessitates the introduction of dynamical bosonic degrees of freedom. This allows for a variety of bag scenarios (including the 'endopionic' bag). We then consider explicit isospin symmetry breaking for hybrid bag models with a nonlinear mesonic sector. An intimate relationship is revealed between the effects of a quark mass difference and the time-dependent bosonic solutions found for the purely mesonic case. It is reflected in a nontrivial interdependence between quark and meson masses, bag radius and chiral angle. We provide an especially extensive list of references for the topics discussed in this report. (orig.)
Observation of the topological soliton state in the Su-Schrieffer-Heeger model
Meier, Eric J; Gadway, Bryce
2016-01-01
The Su-Schrieffer-Heeger (SSH) model, which captures the most striking transport properties of the conductive organic polymer $trans$-polyacetylene, provides perhaps the most basic model system supporting topological excitations. The alternating bond pattern of polyacetylene chains is captured by the bipartite sublattice structure of the SSH model, emblematic of one-dimensional chiral symmetric topological insulators. This structure supports two distinct nontrivial topological phases, which, when interfaced with one another or with a topologically trivial phase, give rise to topologically-protected, dispersionless boundary states. Using $^{87}$Rb atoms in a momentum-space lattice, we realize fully-tunable condensed matter Hamiltonians, allowing us to probe the dynamics and equilibrium properties of the SSH model. We report on the experimental quantum simulation of this model and observation of the localized topological soliton state through quench dynamics, phase-sensitive injection, and adiabatic preparation...
Soliton scattering in the O(3) model on a torus
Cova, R. J.; Zakrzewski, W. J.
1997-01-01
Using numerical simulations, the stability and scattering properties of the O(3) model on a two-dimensional torus are studied. Its solitons are found to be unstable but can be stabilized by the addition of a Skyrme term to the Lagrangian. Scattering at right angles with respect to the initial direction of motion is observed in all cases considered. The model has no solutions of degree one, so when a field configuration that resembles a soliton is considered, it shrinks to become infinitely th...
About chiral models of dense matter and its magnetic properties
The chiral models of dense nucleon matter are discussed. The quark matter with broken chiral symmetry is described. The magnetic properties of dense matter are presented and conclusions are given. 37 refs. (A.S.)
Cheh, Jigger; Zhao, Hong
2011-01-01
In this paper we demonstrate the direct evidence of solitons in graphene by means of molecular dynamics simulations and mathematical analysis. It shows various solitons emerge in the graphene flakes with two different chiralities by cooling procedures. They are in-plane longitudinal and transverse solitons. Their propagations and collisions are studied in details. A soliton solution is derived by making several valid simplifications. We hope it shed light on understanding the unusual thermal ...
Govindarajan, T. R.
1998-01-01
The existence of ring-like and knotted solitons in O(3) non-linear sigma model is analysed. The role of isotopy of knots/links in classifying such solitons is pointed out. Appearance of torus knot solitons is seen.
Soliton laser: A computational two-cavity model
Berg, P.; If, F.; Christiansen, Peter Leth;
1987-01-01
An improved computational two-cavity model of the soliton laser proposed and designed by Mollenauer and Stolen [Opt. Lett. 9, 13 (1984)] is obtained through refinements of (i) the laser cavity model, (ii) the pulse propagation in the fiber cavity, and (iii) the coupling between the two cavities. As...
Quantized Solitons in the Extended Skyrme-Faddeev Model
L. A. Ferreira
2011-01-01
Full Text Available The construction of axially symmetric soliton solutions with non-zero Hopf topological charges according to a theory known as the extended Skyrme-Faddeev model, was performed in [1]. In this paper we show how masses of glueballs are predicted within this model.
Toroidal halos in a nontopological soliton model of dark matter
Soliton type solutions of an axionlike scalar model with self-interaction are analyzed further as a toy model of dark matter halos. For a 'nonlinear superposition' of round and flattened configurations we found ringlike substructures in the density profile similarly as has been inferred for our Galaxy from the observed excess of the diffuse component of cosmic gamma rays
Lectures on the soliton theory of nucleons
In these lectures we describe models in which the pion field or, more precisely, the chiral fields, are responsible for the binding of quarks in the nucleon. Such bound states in which the quarks constitute a source for the chiral fields, which, in turn, bind the quarks to each other, are called solitons. The starting point for such theories or models are chiral invariant lagrangians. They are not derived from QCD. The Skyrme lagrangian is simpler in that it involves only chiral fields and no quarks. However it may be understood as an effective lagrangian from which the quark degrees of freedom have been integrated out. It is not yet clear to what extent various models are equivalent. The description of the nucleon in these lectures may be viewed as an extension of the T.D. Lee solitons so as to include the pionic degree of freedom
Nuclei as superposition of topological solitons
The rational map approximation provides an opportunity to describe light nuclei as classical solitons with baryon number B > 1 in the framework of the Skyrme model. The rational map ansatz yields a possibility of factorization of S3 baryon charge into S1 and S2 parts, the phenomenology of the model being strongly affected by the chosen factorization. Moreover, in the fundamental representation superposition of two different soliton factorizations can be used as solution ansatz. The canonical quantization procedure applied to collective degrees of freedom of the classical soliton leads to anomalous breaking of the chiral symmetry and exponential falloff of the energy density of the soliton at large distance, without explicit symmetry breaking terms included. The evolution of the shape of electric form factor as a function of two different factorization soliton mix ratio is investigated. Numerical results are presented. (author)
Solitons in a sigma model with a fermionic determinant
We develop a numerical technique to calculate the fermionic determinant for soliton states with a hedgehog symmetry in three space dimensions based on the phase shift representation. How the divergence builds up in this approach is clarified. An extrapolation procedure is devised which yields an accurately cutoff independent finite answer. We find that the non-linear sigma model coupled to colored fermions does not seem to support soliton solutions although solutions exist if only scale variations are taken into account. Even on adding a Skyrme quartic term to the action, we find oscillating configurations which are able to lower the energy of the system, possibly without bound
The energy levels of the heavy flavour baryons in the topological soliton model
The energy levels of the charm and bottom as well as the mixed flavour hyperons are calculated with the model in which the hyperons are described as bound states of a topological SU(2) soliton and K-, D- and B-mesons. The spectra are obtained in a modified version of the Skyrme model where the chiral symmetry breaking term in the Lagrangian density is modified so as to incorporate the different values of the decay constants of the mesons of different flavour. The predicted strange and charmed hyperon spectra are in very good agreement with the empirical values, while the bottom hyperon energies that are more sensitive to the short range dynamics are somewhat below the empirical values. The predicted hyperfine spectra are remarkably close to those obtained with the constituent quark model, more or less independently of the short-distance properties of the effective Lagrangian. We suggest that this feature reflects the presence of an induced nonabelian gauge potential generated by the interplay between 'fast' and 'slow' degrees of freedom in the meson-soliton system. (orig.)
N phi state in chiral quark model
Huang, F; Zhang, Z Y
2006-01-01
The structures of N phi states with spin-parity J^{p}=3/2^- and J^p=1/2^- are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground states, the binding energy of the deuteron, the nucleon-nucleon (NN) scattering phase shifts, and the hyperon-nucleon (YN) cross sections. The channel coupling of N phi and Lambda K* is considered, and the effect of the tensor force which results in the mixing of S and D waves is also investigated. The results show that the N phi state has an attractive interaction, and in the extended chiral SU(3) quark model such an attraction plus the channel coupling effect can consequently make for an N phi quasi-bound state with several MeV binding energy.
CHARACTERIZATION AND MODELING OF SOLITON TRANSMISSION AT 2.5 GB/S OVER 200 KM
KHALID A. S. AL-KHATEEB
2010-09-01
Full Text Available Soliton characteristics and soliton transmission have been simulated using a VPI simulator. Simulation was also used to construct and study a soliton communication system. Near soliton pulses emitted by an actively mode-locked laser is then compressed in a dispersion-compensating fiber (DCF to produce solitons. The effects of non-linearity and active pre-chirping of mode-locked laser diode sources were also investigated. Assessment on a modeled system using real data shows that propagation over 250 km at 2.5 Gb/s in standard fibers with 20 ps pulse widths is possible in the 1550 nm wavelength range.
Toy model for two chiral nonets
Fariborz, A H; Schechter, J; Fariborz, Amir H.; Jora, Renata; Schechter, Joseph
2005-01-01
Motivated by the possibility that nonets of scalar mesons might be described as mixtures of "two quark" and "four quark" components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact with each other. Although the "two quark" and "four quark" chiral fields transform identically under SU(3)$_L \\times$ SU(3)$_R$ transformations they transform differently under the U(1)$_A$ transformation which essentially counts total (quark + antiquark) content of the mesons. To implement this we formulate an effective Lagrangian which mocks up the U(1)$_A$ behavior of the underlying QCD. We derive generating equations which yield Ward identity type relations based only on the assumed symmetry structure. This is applied to the mass spectrum of the low lying pseudoscalars and scalars. as well as their "excitations". Assuming isotopic spin invariance, it is possible to disentangle the amount of"two quark" vs."four quark" content in the pseudoscalar $\\pi, K ,\\eta...
Role of structural factors in formation of chiral magnetic soliton lattice in Cr{sub 1/3}NbS₂
Volkova, L. M.; Marinin, D. V. [Institute of Chemistry, Far Eastern Branch of the Russian Academy of Sciences, 690022 Vladivostok (Russian Federation)
2014-10-07
The sign and strength of magnetic interactions not only between nearest neighbors, but also for longer-range neighbors in the Cr{sub 1/3}NbS₂ intercalation compound have been calculated on the basis of structural data. It has been found that left-handed spin helices in Cr{sub 1/3}NbS₂ are formed from strength-dominant at low temperatures antiferromagnetic (AFM) interactions between triangular planes of Cr³⁺ ions through the plane of just one of two crystallographically equivalent diagonals of side faces of embedded into each other trigonal prisms building up the crystal lattice of magnetic Cr³⁺ ions. These helices are oriented along the c axis and packed into two-dimensional triangular lattices in planes perpendicular to these helices directions and lay one upon each other with a displacement. The competition of the above AFM helices with weaker inter-helix AFM interactions could promote the emergence of a long-period helical spin structure. One can assume that in this case, the role of Dzyaloshinskii-Moriya interaction consists of final ordering and stabilization of chiral spin helices into a chiral magnetic soliton lattice. The possibility of emergence of solitons in M{sub 1/3}NbX{sub 2} and M{sub 1/3}TaX₂ (M = Cr, V, Ti, Rh, Ni, Co, Fe, and Mn; X = S and Se) intercalate compounds has been examined. Two important factors caused by the crystal structure (predominant chiral magnetic helices and their competition with weaker inter-helix interactions not destructing the system quasi-one-dimensional character) can be used for the crystal chemistry search of solitons.
Structure functions in the chiral bag model
We calculate the structure functions of an isoscalar nuclear target for the deep inelastic scattering by leptons in an extended version of the chiral bag model which incorporates the qanti q structure of the pions in the cloud. Bjorken scaling and Regge behavior are satisfied. The model calculation reproduces the low-x behavior of the data but fails to explain the medium- to large-x behavior. Evolution of the quark structure functions seem inevitable to attempt a connection between the low-energy models and the high-energy behavior of quantum chromodynamics. (orig.)
Structure functions in the chiral bag model
Sanjose, V.; Vento, V.
1989-07-13
We calculate the structure functions of an isoscalar nuclear target for the deep inelastic scattering by leptons in an extended version of the chiral bag model which incorporates the qanti q structure of the pions in the cloud. Bjorken scaling and Regge behavior are satisfied. The model calculation reproduces the low-x behavior of the data but fails to explain the medium- to large-x behavior. Evolution of the quark structure functions seem inevitable to attempt a connection between the low-energy models and the high-energy behavior of quantum chromodynamics. (orig.).
Flattened halos in a nontopological soliton model of dark matter
Soliton type solutions of a scalar model with a Φ6 self-interaction are analyzed for their density profiles as toy model of dark matter halos. We construct exact solutions with nontrivial ellipticity due to angular momentum and propose a 'nonlinear superposition' of round and flattened halos in order to improve the scaling relations and the correspondence of the predicted rotation curves to the empirical Burkert fit
Modelling of mirror mode structures as propagating slow magnetosonic solitons
K. Stasiewicz
2009-12-01
Full Text Available Cluster measurements in the magnetosheath with spacecraft separations of 2000 km indicate that magnetic pulsations interpreted as mirror mode structures are not frozen in plasma flow, but do propagate with speeds of up to ~50 km/s. Properties of these pulsations are shown to be consistent with propagating slow magnetosonic solitons. By using nonlinear two fluid theory we demonstrate that the well known classical mirror instability condition corresponds to a small subset in a continuum of exponentially varying solutions. With the measured plasma moments we have determined parameters of the polybaric pressure model in the region of occurrence of mirror type structures and applied it to numerical modelling of these structures. In individual cases we obtain excellent agreement between observed mirror mode structures and numerical solutions for magnetosonic solitons.
Nucleon Properties from Approximating Chiral Quark Sigma Model
Abu-Shady, M
2009-01-01
We apply the approximating chiral quark model. This chiral quark model is based on an effective Lagrangian which the interactions between quarks via sigma and pions mesons. The field equations have been solved in the mean field approximation for the hedgehog baryon state. Good results are obtained for nucleon properties in comparison with original model.
Dihyperons in chiral color dielectric model
S C Phatak
2003-11-01
The mass of the dibaryon having spin, parity =0+, isospin = 0 and strangeness -2 is computed using chiral color dielectric model. The bare wave function is constructed as a product of two color-singlet three-quark clusters and then it is properly antisymmetrized by considering appropriate exchange operators for spin, ﬂavor and color. Color magnetic energy due to gluon exchange, meson self energy and energy correction due to center of mass motion are computed. The calculation shows that the mass of the particle is 80 to 160 MeV less than twice mass.
The theta^+ baryon in soliton models: large Nc QCD and the validity of rigid-rotor quantization
Cohen, T D
2003-01-01
A light collective $\\theta^+$ baryon state (with strangeness +1) was predicted via rigid-rotor collective quantization of SU(3) chiral soliton models. This paper explores the validity of this treatment. It is shown that predictions of exotic baryon properties based on this approximation do not follow from large $N_c$ QCD. A number of rather general analyses lead to this conclusion. These include an analysis of the baryon's width, a comparison of the predictions with general large $N_c$ consistency conditions of the Gervais-Sakita-Dashen-Manohar type; an application of the technique to QCD in the limit where the quarks are heavy; a comparison of this method with the vibration approach of Callan and Klebanov; and the $1/N_c$ scaling of the excitation energy. The origin of the problem lies in a flaw in the original rigid-rotor collective quantization treatment which implicitly assumes that the collective motion is orthogonal to vibrational motion. This is untrue for chiral soliton models: the Wess-Zumino term in...
Moduli stabilisation for chiral global models
Cicoli, Michele [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Abdus Salam International Centre for Theoretical Physics, Trieste (Italy); Mayrhofer, Christoph [Heidelberg Univ. (Germany). Inst. fuer Theoretische Physik; Valandro, Roberto [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik
2011-10-15
We combine moduli stabilisation and (chiral) model building in a fully consistent global set-up in Type IIB/F-theory. We consider compactifications on Calabi-Yau orientifolds which admit an explicit description in terms of toric geometry. We build globally consistent compactifications with tadpole and Freed-Witten anomaly cancellation by choosing appropriate brane set-ups and world-volume fluxes which also give rise to SU(5)- or MSSM-like chiral models. We fix all the Kaehler moduli within the Kaehler cone and the regime of validity of the 4D effective field theory. This is achieved in a way compatible with the local presence of chirality. The hidden sector generating the non-perturbative effects is placed on a del Pezzo divisor that does not have any chiral intersections with any other brane. In general, the vanishing D-term condition implies the shrinking of the rigid divisor supporting the visible sector. However, we avoid this problem by generating r
Aspects of solitons in noncommutative field theories. The modified Ward model
In this thesis several aspects of solutions to the equations of motions to noncommutative field theories are investigated in detail. The main focus of the analysis is on the integrable chiral or modified unitary sigma model with U(n)-valued fields as introduced by Ward and its noncommutative extension where the above mentioned new solutions arise. Of particular interest in this context are to us the question of stability of static solitons and the applicability of the so-called adiabatic approach to as a means to approximate time-dependent solutions by geodesic motion in the moduli space of static solutions. After some introductory remarks we proceed to present the Ward model together with its noncommutative extension and give a unified exposition of its known static solutions. This model, as the prime example of an almost Lorentz-invariant field theory in 1+2 dimensions, has several virtues which make its analysis worthwhile. First of all it is integrable thus allowing for powerful, well developed, techniques to generate soliton solutions. At the same time these feature interaction among them. Furthermore, the commutative counterpart of the Ward model has been investigated in great detail such that many results are available for comparison. Next, the question of stability for the present static solutions is considered. This stability is governed by the quadratic form of the fluctuations, which, upon concentrating on the case of diagonal U(1) solutions, is explicitly computed. We show that the considered solutions are stable within a certain subsector of possible configurations, namely the grassmannian ones, and become unstable upon embedding them into the full unitary sigma model. Finally, we remark on some possible generalization of these results. This subject is followed, after a brief review of time-dependent Ward model solutions, by the application of the adiabatic approach, as proposed by Manton, to the static solutions. (orig.)
Nontopological soliton in the Polyakov quark-meson model
Jin, Jinshuang; Mao, Hong
2016-01-01
Within a mean-field approximation, we study a nontopological soliton solution of the Polyakov quark-meson model in the presence of a fermionic vacuum term with two flavors at finite temperature and density. The profile of the effective potential exhibits a stable soliton solution below a critical temperature T ≤Tχc for both the crossover and the first-order phase transitions, and these solutions are calculated here with appropriate boundary conditions. However, it is found that only if T ≤Tdc is the energy of the soliton MN less than the energy of the three free constituent quarks 3 Mq . As T >Tdc , there is an instant delocalization phase transition from hadron matter to quark matter. The phase diagram together with the location of a critical end point has been obtained in the T and μ plane. We notice that two critical temperatures always satisfy Tdc≤Tχc . Finally, we present and compare the result of thermodynamic pressure at zero chemical potential with lattice data.
Nontopological Soliton in the Polyakov Quark Meson Model
Jin, Jinshuang
2016-01-01
In mean field approximation, we study a nontopological soliton of Polyakov Quark Meson Model in the presence of fermionic vacuum term with two flavors at finite temperature and density. The behavior of the effective potential evolving with temperature supports the existence of the stable soliton solution as long as $T\\leq T_{\\chi}^c$ for both crossover and first-order phase transition, and these solutions are calculated with some appropriate boundary conditions. However, it is found that only if $T\\leq T^c_d$, the energy of the soliton $M_N$ is less than the energy of three free constituent quarks $3M_q$. As $T> T^c_d$, there is a instant delocalization phase transition from hadron matter to quark matter. The phase diagram together with the location of critical end point (CEP) has been obtained in $T$ and $\\mu$ plane. We notice that two critical temperatures always satisfy $T^c_d\\leq T_{\\chi}^c$. In the end, we present and compare the result for temperature variation of thermodynamic pressure at zero chemical...
Lagrangian Formulation of the General Modified Chiral Model
Ioannidou, Theodora; Zakrzewski, Wojtek
1998-01-01
We present a Lagrangian formulation for the general modified chiral model. We use it to discuss the Hamiltonian formalism for this model and to derive the commutation relations for the chiral field. We look at some explicit examples and show that the Hamiltonian, containing a contribution involving a Wess-Zumino term, is conserved, as required.
Toy model for two chiral nonets
Motivated by the possibility that nonets of scalar mesons might be described as mixtures of 'two quark' and 'four quark' components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar partners) interact with each other. Although the 'two quark' and 'four quark' chiral fields transform identically under SU(3)LxSU(3)R transformations, they transform differently under the U(1)A transformation which essentially counts total (quark+antiquark) content of the mesons. To implement this, we formulate an effective Lagrangian which mocks up the U(1)A behavior of the underlying QCD. We derive generating equations which yield Ward identity type relations based only on the assumed symmetry structure. This is applied to the mass spectrum of the low lying pseudoscalars and scalars, as well as their 'excitations'. Assuming isotopic spin invariance, it is possible to disentangle the amount of 'two quark' vs 'four quark' content in the pseudoscalar π,K,η-type states and in the scalar κ-type states. It is found that a small 'four quark' content in the lightest pseudoscalars is consistent with a large 'four quark' content in the lightest of the scalar κ mesons. The present toy model also allows one to easily estimate the strength of a 'four quark' vacuum condensate. There seems to be a rich and interesting structure
Cao, Gaoqing
2016-01-01
We study the inhomogeneous solitonic modulation of chiral condensate within the effective Nambu--Jona-Lasinio model when a constant external magnetic field is present. The self-consistent Pauli-Villars regularization scheme is adopted to manipulate the ultraviolet divergence encountered in the thermodynamic quantities. In order to determine the chiral restoration lines efficiently, a new kind of Ginzburg-Landau expansion approach is proposed here. At zero temperature, we find that both the upper and lower boundaries of the solitonic modulation oscillate with the magnetic field in the $\\mu$--$B$ phase diagram which is actually the de Hass-van Alphan (dHvA) oscillation. It is very interesting to find out how the tricritical Lifshitz point $(T_L,\\mu_L)$ evolves with the magnetic field: There are also dHvA oscillations in the $T_L$--$B$ and $\\mu_L$--$B$ curves, though the tricritical temperature $T_L$ increases monotonically with the magnetic field.
Baryons as Solitons in Quantum SU(2) Skyrme Model
Acus, A
1999-01-01
This paper is a PhD thesis defended at Institute of Theoretical Physics and Astronomy on 18 December, 1998. The following (abbreviated) statements represent the main results of the work: 1.Each of SU(2) representation j yields the different quantum Lagrangian density. As a consequence, theoretical observables depend on representation j which can be treated as a new phenomenological parameter. 2.Quantum chiral solitons exist and possess asymptotic behaviour consistent with the massive Yukawa field fall. The asymptotic shape and PCAC relation leads to the correct asymptotic equation coinciding with contribution of explicitly broken term. 3.A nucleon and \\Delta_{33}-resonance are the only stable states for irreducible representations j=3/2 and j=2. Unphysical tower of states l_{spin} =l_{isospin} is, therefore, terminated by choosing the appropriate SU(2) representations. 4.Higher spin l> 1/2 quantum states are not "spherically symmetric". The Hamiltonian density function depends on the polar angle theta. 5.Each...
The non-topological, color dielectric, soliton model
An essential feature of quantum chromcodynamics is the confinement of quarks and gluons in localized, color-singlet states. This has been effected by models through the introduction of a color function κ and magnetic permittivity μ = κ-1. In regions of confinement, such as the interior of a ''bag,'' κ ≅ 1, while in the vacuum, κ → 0. Although the discussion is concerned primarily with the Friedberg-Lee non-topological soliton model, much of the material presented carries over to other color-dielectric soliton models and in some cases analogies or differences are indicated. Soliton models are characterized by the introduction of a scalar field (here denoted by σ) which is to be identified with the gluon condensate. The σ-field is both a Lorentz scalar and color singlet; it has the quantum numbers of the vacuum. It is not a fundamental field, but an effective field. It plays a role similar to plasmons in an electron gas, or deformation modes in nuclear collective motion. The model has been extended beyond the original classical interpretation to permit quantumdynamical calculations. The effective Lagrangian contains the field and its time derivative, so that a Hamiltonian can be constructed which contains the field and its conjugate momentum. Methods familiar from nuclear theory can therefore be used to construct fully quantal states of the system. In doing so, one can employ the coherent (or, more generally, the single mode) state approximation for the scalar field part of the state vector. This is related to the mean field approximation, but is quantal. 26 refs., 1 fig
Circular dichroism of graphene oxide： the chiral structure model
Jing CAO; Hua-Jie YIN; Rui SONG
2013-01-01
We have observed the circular dichroism signal of dilute graphene oxide （GO）, then systematically investigated the chirality of GO and established a probable chiral unit model, This study may open up a new field for understanding the structure of GO and lay the foundation for fabrication of GO-based materials.
Hadron Structure Functions within a Chiral Quark Model
Weigel, H.(Physics Department, Stellenbosch University, Matieland 7602, South Africa); Gamberg, L.(Department of Physics, Penn State University-Berks, Reading, PA, 19610, U.S.A.)
2000-01-01
We outline a consistent regularization procedure to compute hadron structure functions within bosonized chiral quark models. We impose the Pauli--Villars scheme, which reproduces the chiral anomaly, to regularize the bosonized action. We derive the Compton amplitude from this action and utilize the Bjorken limit to extract structure functions that are consistent with the scaling laws and sum rules of deep inelastic scattering.
Skyrmion model in 2+1 dimensions with soliton bound states
Piette, B.; Zakrzewski, W.J. (Dept. of Mathematical Sciences, Univ. Durham (United Kingdom))
1993-03-22
We consider a class of skyrmion models in 2+1 dimensions which possess bound stable solitons. We show that these models have one-soliton solutions as well as static solutions corresponding to their bound states. We study the scattering and stability properties of these solutions, compute their energies and estimate their binding energies. (orig.).
Currents, charges, and canonical structure of pseudodual chiral models
We discuss the pseudodual chiral model to illustrate a class of two-dimensional theories which have an infinite number of conservation laws but allow particle production, at variance with naive expectations. We describe the symmetries of the pseudodual model, both local and nonlocal, as transmutations of the symmetries of the usual chiral model. We refine the conventional algorithm to more efficiently produce the nonlocal symmetries of the model, and we discuss the complete local current algebra for the pseudodual theory. We also exhibit the canonical transformation which connects the usual chiral model to its fully equivalent dual, further distinguishing the pseudodual theory
Vertex decoupling and quark deconfinement in soliton bag model at finite temperature
By means of the Matsubara Green's function method, the temperature dependence of coupling constant gqqδ in soliton bag mode is investigated. It is found gqqδ will decrease as temperature increases in high temperature region and will approach zero at critical temperature Tc. The quark deconfinement phase transition in soliton bag model is discussed
Collective coordinate approximation to the scattering of solitons in the (1+1) dimensional NLS model
Baron, H E; Zakrzewski, W J
2013-01-01
We present a collective coordinate approximation to model the dynamics of two interacting nonlinear Schr\\"odinger (NLS) solitons. We discuss the accuracy of this approximation by comparing our results to those of the full numerical simulations and find that it is remarkably accurate not only when the solitons are some distance apart but also during their interaction.
Collective coordinate approximation to the scattering of solitons in the (1+1) dimensional NLS model
Baron, H. E.; Luchini, G.; Zakrzewski, W. J.
2014-07-01
We present a collective coordinate approximation to model the dynamics of two interacting nonlinear Schrödinger solitons. We discuss the accuracy of this approximation by comparing our results with those of the full numerical simulations and find that the approximation is remarkably accurate when the solitons are some distance apart, and quite reasonable also during their interaction.
Collective coordinate approximation to the scattering of solitons in the (1+1) dimensional NLS model
We present a collective coordinate approximation to model the dynamics of two interacting nonlinear Schrödinger solitons. We discuss the accuracy of this approximation by comparing our results with those of the full numerical simulations and find that the approximation is remarkably accurate when the solitons are some distance apart, and quite reasonable also during their interaction. (paper)
Collective coordinate approximation to the scattering of solitons in the (1+1) dimensional NLS model
Baron, H.E.; Zakrzewski, W. J.; Luchini, G.
2013-01-01
We present a collective coordinate approximation to model the dynamics of two interacting nonlinear Schrödinger solitons. We discuss the accuracy of this approximation by comparing our results with those of the full numerical simulations and find that the approximation is remarkably accurate when the solitons are some distance apart, and quite reasonable also during their interaction.
Generating a soliton splash through variational modelling and experiments
Kalogirou, Anna; Bokhove, Onno
2015-11-01
Mathematical modelling of water waves in tanks with wave generators is demonstrated by investigating variational methods asymptotically and numerically. A reduced potential flow water wave model is derived using variational techniques, which is based on the assumptions of waves with small amplitude and large wavelength. This model consists of a set of modified Benney-Luke equations describing the deviation from the still water surface η (x , y , t) and the bottom potential Φ (x , y , t) , and includes a time-dependent gravitional potential mimicking a removable ``sluice gate''. The asymptotic model is solved numerically using the automated system Firedrake. In particular, a (dis)continuous Galerkin finite element method is used, together with symplectic integrators for the time discretisation. As a validation, the numerical results are compared to a soliton splash experiment in a long water channel with a contraction at its end, resulting after a sluice gate is removed at a finite time.
BRST-BFV quantization of chiral Schwinger model
The BRST-BFV procedure of quantization is applied to establish, in a gauge independent manner, the equivalence of the gauge noninvariant and gauge invariant formulations of the Chiral Schwinger model. (author). 14 refs
BRST-BFV quantization of Chiral Schwinger model
The BRST-BFV procedure of quantization is applied to establish, in a gauge independent manner, the equivalence of the gauge noninvariant and gauge invariant formulations of the Chiral Schwinger model. (author). 14 refs
Chiral-particle Approach to Hadrons in an Extended Chiral ($\\sigma,\\pi,\\omega$) Mean-Field Model
Uechi, Schun T
2010-01-01
The chiral nonlinear ($\\sigma,\\pi,\\omega$) mean-field model is an extension of the conserving nonlinear (nonchiral) $\\sigma$-$\\omega$ hadronic mean-field model which is thermodynamically consistent, relativistic and Lorentz-covariant mean-field theory of hadrons. In the extended chiral ($\\sigma,\\pi,\\omega$) mean-field model, all the masses of hadrons are produced by chiral symmetry breaking mechanism, which is different from other conventional chiral partner models. By comparing both nonchiral and chiral mean-field approximations, the effects of chiral symmetry breaking to the mass of $\\sigma$-meson, coefficients of nonlinear interactions, coupling ratios of hyperons to nucleons and Fermi-liquid properties are investigated in nuclear matter, hyperonic matter, and neutron stars.
Meson phenomenology and phase transitions in nonlocal chiral quark models
Carlomagno, J. P.; Gomez Dumm, D.; Pagura, V.; Scoccola, N. N.
2015-07-01
We study the features of nonlocal chiral quark models that include wave function renormalization. Model parameters are determined from meson phenomenology, considering different nonlocal form factor shapes. In this context we analyze the characteristics of the deconfinement and chiral restoration transitions at finite temperature and chemical potential, introducing the couplings of fermions to the Polyakov loop for different Polyakov potentials. The results for various thermodynamical quantities are compared with data obtained from lattice QCD calculations.
Zakrzewski, Wojtek; Baron, Helen
2014-01-01
We investigate the validity of collective coordinate approaximations to the scattering of solitons in several classes of models in (1+1) dimensional field theory models. We look at models which are deformations of the sine-Gordon (SG) or the nonlinear Schr\\"odinger (NLS) model as they posses solitons which are topological (SG) or non-topological (NLS). Our deformations preserve their topology (SG), but changes their integrability properties, either completely or partially (models become `quas...
Soliton-antisoliton scattering configurations in a noncommutative sigma model in 2+1 dimensions
In this paper we study the noncommutative extension of a modified U(n) sigma model in 2+1 dimensions. Using the method of dressing transformations, an iterative approach for the construction of solutions from a given seed solution, we demonstrate the construction of multi-soliton and soliton-antisoliton configurations for general n. As illustrative examples we discuss U(3) solitons and consider the head-on collision of a U(2) soliton and an antisoliton explicitly, which will result in a 90 deg. angle scattering. Further we discuss the head-on collision of one U(2) soliton with two antisolitons. This results in a 60 deg. angle scattering. (author)
Baron, H. E.; Zakrzewski, W. J.
2016-06-01
We investigate the validity of collective coordinate approximations to the scattering of two solitons in several classes of (1+1) dimensional field theory models. We consider models which are deformations of the sine-Gordon (SG) or the nonlinear Schrödinger (NLS) model which posses soliton solutions (which are topological (SG) or non-topological (NLS)). Our deformations preserve their topology (SG), but change their integrability properties, either completely or partially (models become `quasi-integrable').
Computational modeling of femtosecond optical solitons from Maxwell's equations
Goorjian, Peter M.; Taflove, Allen; Joseph, Rose M.; Hagness, Susan C.
1992-01-01
An algorithm is developed that permits the direct time integration of full-vector nonlinear Maxwell's equations. This capability permits the modeling of both linear and nonlinear instantaneous and dispersive effects in the electric polarization in material media. The modeling of the optical carrier is retained. The fundamental innovation is to notice that it is possible to treat the linear and nonlinear convolution integrals, which describe the dispersion, as new dependent variables. A coupled system of nonlinear second-order ordinary differential equations can then be derived for the linear and nonlinear convolution integrals, by differentiating them in the time domain. These equations, together with Maxwell's equations, are solved to determine the electromagnetic fields in nonlinear dispersive media. Results are presented of calculations in one dimension of the propagation and collision of femtosecond electromagnetic solitons that retain the optical carrier, taking into account as the Kerr and Raman interactions.
Sigma-model soliton intersections from exceptional calibrations
Portugues, R
2002-01-01
A first-order `BPS' equation is obtained for 1/8 supersymmetric intersections of soliton-membranes (lumps) of supersymmetric (4+1)-dimensional massless sigma models, and a special non-singular solution is found that preserves 1/4 supersymmetry. For 4-dimensional hyper-K\\"ahler target spaces ($HK_4$) the BPS equation is shown to be the low-energy limit of the equation for a Cayley-calibrated 4-surface in $\\bE^4\\times HK_4$. Similar first-order equations are found for stationary intersections of Q-lump-membranes of the massive sigma model, but now generic solutions preserve either 1/8 supersymmetry or no supersymmetry, depending on the time orientation.
D-brane Solitons in Supersymmetric Sigma-Models
Gauntlett, J P; Tong, D; Townsend, P K; Gauntlett, Jerome P.; Portugues, Rubén; Tong, David; Townsend, Paul K.
2001-01-01
Massive D=4 N=2 supersymmetric sigma models typically admit domain wall (Q-kink) solutions and string (Q-lump) solutions, both preserving 1/2 supersymmetry. We exhibit a new static 1/4 supersymmetric `kink-lump' solution in which a string ends on a wall, and show that it has an effective realization as a BIon of the D=4 super DBI-action. It is also shown to have a time-dependent Q-kink-lump generalization which reduces to the Q-lump in a limit corresponding to infinite BI magnetic field. All these 1/4 supersymmetric sigma-model solitons are shown to be realized in M-theory as calibrated, or `Q-calibrated', M5-branes in an M-monopole background.
On SU(3) effective models and chiral phase-transition
Tawfik, Abdel Nasser
2015-01-01
The sensitivity of Polyakov Nambu-Jona-Lasinio (PNJL) model as an effective theory of quark dynamics to chiral symmetry has been utilized in studying the QCD phase-diagram. Also, Poyakov linear sigma-model (PLSM), in which information about the confining glue sector of the theory was included through Polyakov-loop potential. Furthermore, from quasi-particle model (QPM), the gluonic sector of QPM is integrated to LSM in order to reproduce recent lattice calculations. We review PLSM, QLSM, PNJL and HRG with respect to their descriptions for the chiral phase-transition. We analyse chiral order-parameter M(T), normalized net-strange condensate Delta_{q,s}(T) and chiral phase-diagram and compare the results with lattice QCD. We conclude that PLSM works perfectly in reproducing M(T) and Delta_{q,s}(T). HRG model reproduces Delta_{q,s}(T), while PNJL and QLSM seem to fail. These differences are present in QCD chiral phase-diagram. PLSM chiral boundary is located in upper band of lattice QCD calculations and agree we...
Chiral Transition Within Effective Quark Models under Strong Magnetic Fields
Garcia, Andre Felipe
2013-01-01
In the recently years it has been argued that spectators in heavy ion collisions are responsible for creating a strong magnetic field that could play an important role in the QCD phase transition. In this work we use the SU(2) Nambu--Jona-Lasinio (NJL) model in order to study the chiral transition in quark matter subject to a strong magnetic field. We show some results involving the breaking of chiral symmetry and its restoration at finite temperature and density.
Solitonic description of interface profiles in competition models
Azevedo, T; Menezes, J
2014-01-01
We consider the spatial patterns provided by mean field numerical simulations for two competing species. As all individuals have the same rate of mobility, reproduction and competition, interfaces of empty spaces separating domains of single species are formed by a spontaneous process of symmetry breaking. We construct a Lagrangian formalism for studying the static profile of such interfaces by means of a scalar field theory framework. We identify the number density of empty spaces created by the competition interactions with a function of the energy density in scalar field systems. We then present a potential with $Z_2$ symmetry, which leads to differential equations whose solitonic solutions describe interface profile. Finally, we compare the theoretical results with data from one-dimensional numerical simulation of the Lotka-Volterra equations and show that our model fits well the properties of interfaces.
Yu, Lang; Huang, Mei
2015-01-01
We study the chiral phase transition in the presence of the chiral chemical potential $\\mu_5$ using the two-flavor Nambu--Jona-Lasinio model. In particular, we analyze the reason why one can obtain two opposite behaviors of the chiral critical temperature as a function of $\\mu_5$ in the framework of different regularization schemes. We compare the modifications of the chiral condensate and the critical temperature due to $\\mu_5$ in different regularization schemes, analytically and numerically. Finally, we find that, for the conventional hard-cutoff regularization scheme, the increasing dependence of the critical temperature on the chiral chemical potential is an artifact, which is caused by the fact that it does not include complete contribution from the thermal fluctuations. When the thermal contribution is fully taken into account, the chiral critical temperature should decrease with $\\mu_5$.
Bag constant and deconfinement phase transition in the nontopological soliton bag model
The effective potential in finite temperature and density nontopological soliton bag model is investigated. Based on this, the authors calculate the bag constant which depends on temperature and chemical potential. The property of deconfinement phase transition is analysed
Soliton solutions of an improved quark mass density-dependent model at finite temperature
The improved quark mass density-dependent model (IQMDD) based on soliton bag model is studied at finite temperature. Applying the finite temperature field theory, the effective potential of the IQMDD model and the bag constant B(T) have been calculated at different temperatures. It is shown that there is a critical temperature TC≅110 MeV. We also calculate the soliton solutions of the IQMDD model at finite temperature. It turns out that when TC, there is a bag constant B(T) and the soliton solutions are stable. However, when T>TC the bag constant B(T)=0 and there is no soliton solution, therefore, the confinement of quarks are removed quickly
Rodrigo Cancino L
2007-04-01
Full Text Available En este artículo se presenta un modelo teórico y la simulación computacional correspondiente, que permite analizar los efectos de la propagación de ondas solitónicas en medios biológicos esencialmente quirales. La quiralidad se modela, en este caso, bajo la formulación de Drude, mostrándose los rangos de validez del modelo propuesto. Este modelo considera los efectos no lineales y dispersivos del medio, debido a una dependencia espectral de la señal de entrada y la aproximación de campo cuasi-monocromático, para escribir la ecuación no lineal de Schrödinger y resolverla numéricamente mediante el método espectral de Fourier. Los resultados de nuestras simulaciones muestran el efecto de la variación del factor quiral sobre la impedancia del medio y sobre los coeficientes de transmisión y reflexión. Finalmente se discute, brevemente, la generalización del modelo de Drude para el caso de metamateriales.In this paper a theory model with the corresponding simulations, which permit to analyze the solitonic wave propagation in biological media, is presented. The chirality is modeled as Drude's formulation, showing the validity rank of the model. The model considers nonlinear and dispersive effects due to the spectral dependency of the input signal and the cuasy-monocromatic approach, so as to write the Schrödinger non-linear equation and solving it numerically by means of the spectral Fourier method. The numerical results show the effect of chiral factor variation on the media impedance, transmission and reflection coefficients. Finally, the generalization of the Drude's formulation for the metamaterial case, is briefly discussed.
The fermion in the gauge invariant formulation of the chiral Schwinger model and its relation to the fermion in the anomalous formulation is studied. A gauge invariant fermion operator is constructed that does not give rise to an asymptotic fermion field. It fits in the scheme prepared by generalized Schwinger models. Singularities in the short-distance limit of the chiral Schwinger model in the anomalous formulation lead to the conclusion that it is not a promising starting point for investigations towards realistic (3+1)-dimensional gauge theories with chiral fermion content. A new anomalous (1+1)-dimensional model is studied, the chiral quantum gravity. It is proven to be consistent if only a limited number of chiral fermions couple. The fermion propagator behaves analogously to the one in the massless Thirring model. A general rule is derived for the change of the fermion operator, which is induced by the breakdown of a gauge symmetry. (orig.)
Integrability of a master chiral quantum field model
The paper deals with solution of a master chiral field model in two-dimensional space-time using the quantum method of inverse problem. A dominant role in the approach is played by the idea of relativistic model production on the basis of magnetic model in the scaling limit at S→ infinity. L-M pair of a master chiral field model is discussed. Formulae for regularized quantum Hamiltonian and Bethe-Ansatz above pseudovacuum are derived. The description of excitations and Dirac filling for the ground state is given. Continuous limit from magnetic model above physical vacuum is considered
A Geometric Algorithm to construct new solitons in the O(3) Nonlinear Sigma Model
Barros, M
2003-01-01
The O(3) nonlinear sigma model with boundary, in dimension two, is considered. An algorithm to determine all its soliton solutions that preserve a rotational symmetry in the boundary is exhibited. This nonlinear problem is reduced to that of clamped elastica in a hyperbolic plane. These solutions carry topological charges that can be holographically determined from the boundary conditions. As a limiting case, we give a wide family of new soliton solutions in the free O(3) nonlinear sigma model.
Soliton like excitations on a deformable spin model
We study numerically non-linear excitations on a one-dimensional deformable discrete classical ferromagnetic chain. In the continuum limits the equations of motion are reduced to a Klein-Gordon equation with a Remoissenet - Peyrard substrate potential. From a numerical computation of the discrete system with a suitable choice of the deformability parameters, the solitons solutions are shown to exist and move both with a monotonic oscillating (i.e. nanopteron) and a monotonic non- oscillating tails and also with a non- oscillating tails but with a splitting propagating shape. The stability of all these various solitons shape is confirmed numerically in a greater range of the reduced magnetic field 0≤b≤0.61 compared to the case of a rigid magnetic chain i.e. 0≤b≤0.33. From a kink- antikink and a kink-kink colliding simulation, we found various effects including a bound state of a kink and an antikink as well as a moving kink profile with higher topological charge that appears to be the bound state of two kinks. We also observed a three particles interaction that also arises from a kink-kink collision. The breather that intercalates between the two kinks has length that varies from its minimal value to the maximal one as far as the alternation between an attractive and a repulsive phenomenon is produced. From our results it appears that the value of the shape parameter of the substrate potential or the modified Zeeman energy is a factor of outmost importance when modelling magnetic chains. (author)
Lectures on the soliton theory of nucleons
In the absence of bona fide QCD calculations of nucleon structure (excepting lattice gauge calculations which do not give much detail on the structure of nucleons) new models seem to come up almost every year, all with the claim that QCD will eventually justify them as valid phenomenological models. Other papers show the necessity of implementing simple models (such as the MIT bag model or, more generally, T.D. Lee solitons) with the pionic degree of freedom. In this paper the authors describe models in which it is the pion field or, more precisely, the chiral fields, which are responsible for the binding of quarks in the nucleon. Such bound states in which the quarks constitute a source for the chiral fields, which, in turn, bind the quarks to each other, are called solitons. The starting point for such theories or models are chiral invariant lagrangians, which have been used, in various contexts, for almost a quarter of a century. They are not derived from QCD. It has been argued however that QCD is likely to produce such effective lagrangians for the description of low q phenomena. The Skyrme lagrangian is simpler in that it involves only chiral fields and no quarks. However it may be understood as an effective lagrangian from which the quark degrees of freedom have been integrated out. It is not yet clear to what extent various models are equivalent
Quark matter inside neutron stars in an effective chiral model
An effective chiral model which describes properties of a single baryon predicts that the quark matter relevant to neutron stars, close to the deconfinement density, is in a chirally broken phase. We find the SU(2) model that pion-condensed up and down quark matter is preferred energetically at neutron star densities. It exhibits spin ordering and can posses a permanent magnetization. The equation of state of quark matter with chiral condensate is very well approximated by bag model equation of the state with suitably chosen parameters. We study quark cores inside neutron stars in this model using realistic nucleon equations of state. The biggest quark core corresponds to the second order phase transition to quark matter. Magnetic moment of the pion-condensed quark core is calculated. (author). 19 refs, 10 refs, 1 tab
Ω(ε)States in a Chiral Quark Model
无
2007-01-01
The structures of Ω(ε) states with spin-parity Jp = 5/2-, 3/2-, and 1/2- are dynamically studied in both the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from our previous work, which gave a satisfactory description of the energies of the baryon ground states, the binding energy of the deuteron, the nucleon-nucleon (NN) scattering phase shifts, and the hyperon-nucleon (YN) cross sections. The calculated results show that theΩ(ε) state has an attractive interaction, and in the extended chiral SU(3) quark model such attraction can make for aΩ(ε) quasi-bound state with spin-parity Jp = 3/2- or 5/2- and tie binding energy of about several MeV.
Soliton excitations and stability in a square lattice model of ferromagnetic spin system
Latha, M. M.; Anitha, T.
2015-12-01
We investigate the nature of nonlinear spin excitations in a square lattice model of ferromagnetic (FM) spin system with bilinear and biquadratic interactions. Using the coherent state ansatz combined with the Holstein-Primakoff (HP) bosonic representation of spin operators, the dynamics is found to be governed by a discrete nonlinear equation which possesses soliton solution. The modulational instability aspects of the soliton excitations are analysed for small perturbations in wave vectors.
Chiu, Hong-Yee
1990-01-01
The theory of Lee and Pang (1987), who obtained solutions for soliton stars composed of zero-temperature fermions and bosons, is applied here to quark soliton stars. Model soliton stars based on a simple physical model of the proton are computed, and the properties of the solitons are discussed, including the important problem of the existence of a limiting mass and thus the possible formation of black holes of primordial origin. It is shown that there is a definite mass limit for ponderable soliton stars, so that during cooling a soliton star might reach a stage beyond which no equilibrium configuration exists and the soliton star probably will collapse to become a black hole. The radiation of ponderable soliton stars may alter the short-wavelength character of the cosmic background radiation, and may be observed as highly redshifted objects at z of about 100,000.
Nuclei as topological solitons
The application of the Skyrme model to the construction of interaction and current operators for nuclear systems is reviewed. The long-range behaviors of these operators are found to agree with results of phenomenological meson theories based on effective chiral Lagrangians. The Skyrme model thus provides a compact method for obtaining long-range parts of such operators, consistent with the usual soft-pion theorems as well as with the requirement of current conservation. Predictions of the short-range parts of the operators remain uncertain due to difficulties in solving the equations of motion for the two-nucleon problem. The usual factorized ansatz for the soliton field of the two-nucleon system does not give sufficient accuracy at short range. The possibility of an improvement which would allow the construction of spin and isospin operators for the individual nucleons is discussed. The Skyrme model is discussed in the limit of large baryon number
Self-bound quark matter in the NJL model revisited: from schematic droplets to solitonic lasagne
Buballa, Michael
2012-01-01
The existence and the properties of self-bound quark matter in the NJL model at zero temperature are investigated in mean-field approximation, focusing on inhomogeneous structures with one-dimensional spatial modulations. It is found that the most stable homogeneous solutions which have previously been interpreted as schematic quark droplets are unstable against formation of a one-dimensional soliton-antisoliton lattice. The solitons repel each other, so that the minimal energy per quark is realized in the single-soliton limit. The properties of the solitons and their interactions are discussed in detail, and the effect of vector interactions is estimated. The results may be relevant for the dynamics of expanding quark matter.
Is the Chiral Model equivalent to Wess-Zumino-Witten Model when coupled with Gravity?
Nojiri, Shin'ichi
1996-01-01
We investigate the non-abelian $T$-duality of Wess-Zumino-Witten model. The obtained dual model is equivalent to the model dual to the $SU(2)$ chiral model found by Curtright-Zachos. This might tell that the Wess-Zumino term would be induced when the chiral model couples with gravity.
Minimal quantization of two-dimensional models with chiral anomalies
Two-dimensional gauge models with chiral anomalies - ''left-handed'' QED and the chiral Schwinger model, are quantized consistently in the frames of the minimal quantization method. The choice of the cone time as a physical time for system of quantization is motivated. The well-known mass spectrum is found but with a fixed value of the regularization parameter a=2. Such a unique solution is obtained due to the strong requirement of consistency of the minimal quantization that reflects in the physically motivated choice of the time axis
Distinguishing Standard Model Extensions using Monotop Chirality at the LHC
Allahverdi, Rouzbeh; Dutta, Bhaskar; Gao, Yu; Kamon, Teruki
2015-01-01
We present two minimal extensions of the standard model that gives rise to baryogensis and include heavy color-triplet scalars interacting with a light Majorana fermion that can be the dark matter (DM) candidate. The electroweak charges of the new scalars govern their couplings to quarks of different chirality, which leads to different collider signals. These models predict monotop events at the LHC and the energy spectrum of decay products of highly polarized top quarks can be used to establish the chiral nature of the interactions involving the heavy scalars and the DM.
Vector-meson mass generation in the chiral Schwinger model
It is shown that an arbitrary mass is generated for the vector meson in the chiral Schwinger model, a model which has caused some controversy. Our arguments are based on ambiguities in the dimensional regularization of quantum field theory with γ5. (orig.)
The nucleon-nucleon potential in the chromodielectric soliton model
Koepf, W.; Wilets, L.; Pepin, S.; Stancu, F.
The short and medium range parts of the nucleon-nucleon interaction are being studied in the framework of the chromodielectric soliton model. The model consists of current quarks, gluons in the abelian approximation, and a scalar sigma field which simulates the nonabelian interactions of the gluons and governs the medium through the dielectric function kappa(sigma). Absolute color confinement is effected by the vanishing of the dielectric in vacuum; this also removes the troublesome van der Waals problem. The authors distinguish between spatial confinement, which arises from the self energy of the quarks in medium (excluding MFA contributions), and color confinement which is effected through OGE in the MFA (including the corresponding self energy contributions). The static (adiabatic) energies are computed as a function of deformation (generalized bag separation) in a constrained MFA. Six quark molecular-type wave functions in all important space-spin-isospin-color configurations are included. The gluon propagator is solved in the deformed dielectric medium. The resultant Hamiltonian matrix is diagonalized. Dynamics are handled in the generator coordinate method, which leads to the Hill-Wheeler integral equation. In the present case, this yields a set of coupled equations corresponding to the various configurations. Although this can be approximated by a set of differential equations, they propose to solve the integral equations with some regularization scheme.
Scattering of Topological Solitons on Barriers and Holes of Deformed Sine-Gordon Models
Al-Alawi, Jassem H.; Zakrzewski, Wojtek J.
2008-01-01
We study scattering properties of topological solitons in two classes of models, which are generalizations of the Sine-Gordon model and which have recently been proposed by Bazeia et al. These two classes of models depend on an integer parameter n which, when n=2(for the first class) and n=1 (for the second class), reduce to the Sine-Gordon model. We take the soliton solutions of these models (generalizations of the 'kink' solution of the Sine-Gordon model) and consider their scattering on po...
The soliton sector pf the quantum field associated with the two-dimensional ising model
An anti-periodic finite lattice Hamiltonian is defined through the transfer matrix of the two-dimensional Ising model with anti-periodic boundary conditions in the space direction and periodic boundary conditions in the imaginary time direction. An infinite lattice quantum field theory is obtained by taking limits of vector states on the algebra of observables generated by finite products of spin operators. Explicit representations of spin and energy-momentum operators are obtained in terms of free Fermions acting in a Fermionic Fock space. The infinite lattice energy-momentum spectrum is analogous to the odd spectrum of a free, scalar, massive field theory: in particular, the vacuum and two-particle states are absent. The algebra of observables admits a decomposition into two subalgebras corresponding to the soliton, anti-soliton decomposition. Particular vector states show soliton behavior. The scaling limit is also obtained. An algebraic construction of the soliton sector is given and soliton field operators are defined. It is Shown that the imaginary time soliton two-point function is the two-point function of the disorder operator introduced by Kadanoff and Ceva. (author)
Orbital Angular Momentum in the Chiral Quark Model
Song, Xiaotong
1998-01-01
We developed a new and unified scheme for describing both quark spin and orbital angular momenta in symmetry-breaking chiral quark model. The loss of quark spin in the chiral splitting processes is compensated by the gain of the orbital angular momentum carried by quarks and antiquarks. The sum of both spin and orbital angular momenta carried by quarks and antiquarks is 1/2. The analytic and numerical results for the spin and orbital angular momenta carried by quarks and antiquarks in the nuc...
The effective action approach applied to nuclear chiral sigma model
The nuclear chiral sigma model of nuclear matter is considered by means of the Cornwall-Jackiw-tomboulis (CTJ) effective action. The method provides a very general framework for investigating many important problems: chiral symmetry in nuclear medium, energy density of nuclear ground state, nuclear Schwinger-Dyson (SD) equations, etc. It is shown that the SD equations for sigma-omega mixing are actually not present in this formalism. For numerical computation purposes the Hartree-Fock (HF) approximation for ground state energy density is also presented. (author). 26 refs
Transversity structure of the pion in chiral quark models
Broniowski, Wojciech; Dorokhov, Alexander E
2011-01-01
We describe the chiral quark model evaluation of the transversity Generalized Parton Distributions (tGPDs) and related transversity form factors (tFFs) of the pion. The obtained tGPDs satisfy all necessary formal requirements, such as the proper support, normalization, and polynomiality. The lowest tFFs, after the necessary QCD evolution, compare favorably to the recent lattice QCD determination. Thus the transversity observables of the pion support once again the fact that the spontaneously broken chiral symmetry governs the structure of the Goldstone pion. The proper QCD evolution is crucial in these studies.
Quantum Solitons with Cylindrical Symmetry
Chepilko, N.; Kobushkin, A.; Syamtomov, A.
1993-01-01
Soliton solutions with cylindrical symmetry are investigated within the nonlinear $\\sigma $-model disregarding the Skyrme-stabilization term. The solitons are stabilized by quantization of collective breathing mode and collapse in the $\\hbar \\to 0$ limit. It is shown that for such stabilization mechanism the model, apart from solitons with integer topological number $B$, admits the solitons with half-odd $B$. The solitons with integer $B$ have standard spin-isospin classification, while $B={\\...
Lü, Xing; Peng, Mingshu
2013-03-01
In this paper, the nonautonomous Lenells-Fokas (LF) model is studied with the bilinear method and symbolic computation. Such analytical solutions of the nonautonomous LF model as one-soliton, two-soliton, and earthwormons are derived. Nonautonomous characteristics are then symbolically and graphically investigated, and it is finally found that the soliton velocity is time-dependent, and there exist soliton accelerating and decelerating motions. Further, two necessary conditions for the occurrence of earthwormon acceleration and deceleration (and their alternation) are pointed out. PMID:23556959
The Many Faces of the Chiral Potts Model
Au-Yang, H; Au-Yang, Helen; Perk, Jacques H.H.
1996-01-01
In this talk, we give a brief overview of several aspects of the theory of the chiral Potts model, including higher-genus solutions of the star-triangle and tetrahedron equations, cyclic representations of affine quantum groups, basic hypergeometric functions at root of unity, and possible applications.
Dimensional regularization and perturbative solution of the chiral Schwinger model
The anomalous chiral Schwinger model is regulated by the method of dimensional regularization and is solved by diagrammatic perturbative expansion. It is shown that there is a regulation ambiguity in the solution. The result disagrees with Das's assertion and agrees with that of Jackiw, Rajaraman, and others
Soliton trap in strained graphene nanoribbons
The wavefunction of a massless fermion consists of two chiralities, left handed and right handed, which are eigenstates of the chiral operator. The theory of weak interactions of elementary particle physics is not symmetric about the two chiralities, and such a symmetry-breaking theory is referred to as a chiral gauge theory. The chiral gauge theory can be applied to the massless Dirac particles of graphene. In this paper, we show within the framework of the chiral gauge theory for graphene that a topological soliton exists near the boundary of a graphene nanoribbon in the presence of a strain. This soliton is a zero-energy state connecting two chiralities and is an elementary excitation transporting a pseudo-spin. The soliton should be observable by means of a scanning tunneling microscopy experiment.
Regularization of multi-soliton form factors in sine-Gordon model
Pálmai, T.
2012-08-01
A general and systematic regularization is developed for the exact solitonic form factors of exponential operators in the (1+1)-dimensional sine-Gordon model by analytical continuation of their integral representations. The procedure is implemented in Mathematica. Test results are shown for four- and six-soliton form factors. Catalogue identifier: AEMG_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEMG_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 1462 No. of bytes in distributed program, including test data, etc.: 15 488 Distribution format: tar.gz Programming language: Mathematica [1] Computer: PC Operating system: Cross-platform Classification: 7.7, 11.1, 23 Nature of problem: The multi-soliton form factors of the sine-Gordon model (relevant in two-dimensional physics) were given only by highly non-trivial integral representation with a limited domain of convergence. Practical applications of the form factors, e.g. calculation of correlation functions in two-dimensional condensed matter systems, were not possible in general. Solution method: Using analytic continuation techniques an efficient algorithm is found and implemented in Mathematica, which provides a general and systematic way to calculate multi-soliton form factors in the sine-Gordon model. The package contains routines to compute the two-, four- and six-soliton form factors. Running time: Strongly dependent on the desired accuracy and the number of solitons. For physical rapidities after an initialization of about 30 s, the calculation of the two-, four- and six-soliton form factors at a single point takes approximately 0.5 s, 2.5 s and 8 s, respectively. Wolfram Research, Inc., Mathematica Edition: Version 7.0, Wolfram Research, Inc., Champaign, Illinois, 2008.
Chiral matrix model of the semi-QGP in QCD
Pisarski, Robert D.; Skokov, Vladimir V.
2016-08-01
Previously, a matrix model of the region near the transition temperature, in the "semi"quark gluon plasma, was developed for the theory of S U (3 ) gluons without quarks. In this paper we develop a chiral matrix model applicable to QCD by including dynamical quarks with 2 +1 flavors. This requires adding a nonet of scalar fields, with both parities, and coupling these to quarks through a Yukawa coupling, y . Treating the scalar fields in mean field approximation, the effective Lagrangian is computed by integrating out quarks to one loop order. As is standard, the potential for the scalar fields is chosen to be symmetric under the flavor symmetry of S U (3 )L×S U (3 )R×Z (3 )A, except for a term linear in the current quark mass, mqk. In addition, at a nonzero temperature T it is necessary to add a new term, ˜mqkT2. The parameters of the gluon part of the matrix model are identical to those for the pure glue theory without quarks. The parameters in the chiral matrix model are fixed by the values, at zero temperature, of the pion decay constant and the masses of the pions, kaons, η , and η'. The temperature for the chiral crossover at Tχ=155 MeV is determined by adjusting the Yukawa coupling y . We find reasonable agreement with the results of numerical simulations on the lattice for the pressure and related quantities. In the chiral limit, besides the divergence in the chiral susceptibility there is also a milder divergence in the susceptibility between the Polyakov loop and the chiral order parameter, with critical exponent β -1 . We compute derivatives with respect to a quark chemical potential to determine the susceptibilities for baryon number, the χ2 n. Especially sensitive tests are provided by χ4-χ2 and by χ6, which changes in sign about Tχ. The behavior of the susceptibilities in the chiral matrix model strongly suggests that as the temperature increases from Tχ, that the transition to deconfinement is significantly quicker than indicated by the
Three-dimensional collinearly propagating solitons
The generalized nonlinear Schrödinger equation is modified in order to describe three-dimensional solitons propagating collinearly with a constant velocity. One- and two-soliton solutions are obtained and analysed. When the frequencies of the respective solitons approach, then the effect of the repulsion of the solitons is observed. These solitons are proposed to model photons. (paper)
Three-phase model of a chiral quark bag
Three-phase modification of the model of hybrid chiral quark bag is suggested. Along with the phase of asymptotically free current quarks and completely achromatic meson phase the model contains an intermediate phase including massive quark components. Self-consistent solution of model equations with account of contribution from the Dirac sea is found for (1+1)-dimensional case. The dependence of bag characteristics on theory parameters is investigated in analytical and numerical forms
An Anderson-like model of the QCD chiral transition
Giordano, Matteo; Kovács, Tamás G.; Pittler, Ferenc
2016-06-01
We study the problems of chiral symmetry breaking and eigenmode localisation in finite-temperature QCD by looking at the lattice Dirac operator as a random Hamiltonian. We recast the staggered Dirac operator into an unconventional three-dimensional Anderson Hamiltonian ("Dirac-Anderson Hamiltonian") carrying internal degrees of freedom, with disorder provided by the fluctuations of the gauge links. In this framework, we identify the features relevant to chiral symmetry restoration and localisation of the low-lying Dirac eigenmodes in the ordering of the local Polyakov lines, and in the related correlation between spatial links across time slices, thus tying the two phenomena to the deconfinement transition. We then build a toy model based on QCD and on the Dirac-Anderson approach, replacing the Polyakov lines with spin variables and simplifying the dynamics of the spatial gauge links, but preserving the above-mentioned relevant dynamical features. Our toy model successfully reproduces the main features of the QCD spectrum and of the Dirac eigenmodes concerning chiral symmetry breaking and localisation, both in the ordered (deconfined) and disordered (confined) phases. Moreover, it allows us to study separately the roles played in the two phenomena by the diagonal and the off-diagonal terms of the Dirac-Anderson Hamiltonian. Our results support our expectation that chiral symmetry restoration and localisation of the low modes are closely related, and that both are triggered by the deconfinement transition.
CHIRAL MODEL FOR DENSE, HOT AND STRANGE HADRONIC MATTER
ZSCHIESCHE,D.; PAPAZOGLOU,P.; BECKMANN,C.W.; SCHRAMM,S.; SCHAFFNER-BIELICH,J.; STOCKER,H.; GREINER,W.
1999-06-10
Until now it is not possible to determine the equation of state (EOS) of hadronic matter from QCD. One successfully applied alternative way to describe the hadronic world at high densities and temperatures are effective models like the RMF-models, where the relevant degrees of freedom are baryons and mesons instead of quarks and gluons. Since approximate chiral symmetry is an essential feature of QCD, it should be a useful concept for building and restricting effective models. It has been shown that effective {sigma}-{omega}-models including SU(2) chiral symmetry are able to obtain a reasonable description of nuclear matter and finite nuclei. Recently [4] the authors have shown that an extended SU(3) x SU(3) chiral {sigma}-{omega} model is able to describe nuclear matter ground state properties, vacuum properties and finite nuclei satisfactorily. This model includes the lowest SU(3) multiplets of the baryons (octet and decuplet), the spin-0 and the spin-1 mesons as the relevant degrees of freedom. Here they discuss the predictions of this model for dense, hot, and strange hadronic matter.
Self-trapped optical beams: Spatial solitons
Andrey A Sukhorukov; Yuri S Kivshar
2001-11-01
We present a brief overview of the basic concepts of the theory ofspatial optical solitons, including the soliton stability in non-Kerr media, the instability-induced soliton dynamics, and collision of solitary waves in nonintegrable nonlinear models.
Non-Vortex Topological Solitons of the [InlineMediaObject not available: see fulltext.] Gauge Model
Afanas'ev, K. V.; Gauzshtein, V. V.; Loginov, A. Yu.
2016-06-01
A (2+1)-dimensional [InlineMediaObject not available: see fulltext.] gauge model is investigated. The presence of additional local U(1) symmetry, not associated with a physical gauge field, leads to the existence in the given model of two-dimensional non-vortex topological solitons carrying unquantized magnetic flux. Topological solitons of the given type were found numerically for fixed values of the model parameters. Analytical calculations of some properties of non-vortex topological solitons were performed. Universal dependences of the energy and magnetic flux of a non-vortex topological soliton on a dimensionless combination of parameters of the [InlineMediaObject not available: see fulltext.] gauge model were obtained numerically. A comparative analysis of the properties of a non-vortex topological soliton and an Abrikosov-Nielsen-Olesen classical vortex is provided.
Dimension 2 condensates and Polyakov Chiral Quark Models
Megias, E.; Arriola, E. Ruiz; Salcedo, L. L.
2006-01-01
We address a possible relation between the expectation value of the Polyakov loop in pure gluodynamics and full QCD based on Polyakov Chiral Quark Models where constituent quarks and the Polyakov loop are coupled in a minimal way. To this end we use a center symmetry breaking Gaussian model for the Polyakov loop distribution which accurately reproduces gluodynamics data above the phase transition in terms of dimension 2 gluon condensate. The role played by the quantum and local nature of the ...
Soft Matrix Elements in Non-local Chiral Quark Model
Kotko, Piotr
2009-01-01
Using non-local chiral quark model and currents satisfying Ward-Takahashi identities we analyze Distribution Amplitudes (DA) of photon and pion-to-photon Transition Distribution Amplitudes (TDA) in the low energy regime. Photon DA's are calculated analytically up to twist-4 and reveal several interesting features of photon structure. TDA's calculated in the present model satisfy polynomiality condition. Normalization of vector TDA is fixed by the axial anomaly. We also compute relevant form f...
BFFT formalism applied to the minimal chiral Schwinger model
Natividade, C P; Belvedere, L V
2000-01-01
The minimal chiral Schwinger model is discussed from the Batalin-Fradkin-Fradkina-Tyutin point of view. The conversion of second-class constraints to first-class ones results in an extended gauge-invariant theory which is equivalent for $a=2$ to the vector Schwinger model at the Lagrangian level. Here, we present arguments which show that such equivalence does no exist at the operatorial level.
Soliton-like excitation in a nonlinear model of DNA dynamics with viscosity.
Tabi, Conrad Bertrand; Mohamadou, Alidou; Kofane, Timoleon Crepin
2008-01-01
The study of solitary wave solutions is of prime significance for nonlinear physical systems. The Peyrard-Bishop model for DNA dynamics is generalized specifically to include the difference among bases pairs and viscosity. The small amplitude dynamics of the model is studied analytically and reduced to a discrete complex Ginzburg-Landau (DCGL) equation. Exact solutions of the obtained wave equation are obtained by the mean of the extended Jacobian elliptic function approach. These amplitude solutions are made of bubble solitons. The propagation of a soliton-like excitation in a DNA is then investigated through numerical integration of the motion equations. We show that discreteness can drastically change the soliton shape. The impact of viscosity as well as elasticity on DNA dynamic is also presented. The profile of solitary wave structures as well as the energy which is initially evenly distributed over the lattice are displayed for some fixed parameters. PMID:18193938
Opportunities for collective model and chirality studies at TRIUMF
First predictions for a specific case of the particle-hole-core coupling model which takes advantage of symmetries of a triaxial rotor with γ = 90° are reviewed. Results of the model calculations point towards existence of stable chiral geometry in specific configurations involving high-j orbitals. Next, experimental information on doublet bands built on unique parity, πh11/2νh11/2 intruder states in odd-odd 134Pr is discussed; in particular observed disagreements between electromagnetic transitions within the doublet structures which is pointed out as inconsistent with the simplest models. Finally, the unique experimental infrastructure developed at the Tri-University Meson Facility (TRIUMF) Canada's National Laboratory for Particle and Nuclear Physics is presented including a range of isotopes in the mass 130 region that are accessible as beams and which can possibly yield significant new information in investigations of nuclear chirality. (author)
Hadron Properties in a Chiral Quark-Sigma Model
Rashdan, M; El-Kholy, S; Abu-Shady, M
2011-01-01
Within a chiral quark sigma model in which quarks interact via the exchange of sigma and pi-mesons, hadron properties are investigated. This model of the nucleon and delta is based on the idea that strong QCD forces on very short distances (a small length scales 0.2- 1 fm) result in hidden chiral SU(2)xSU(2) symmetry and that there is a separation of roles between these forces which are responsible for binding quarks in hadrons and the forces which produce absolute confinement. We have solved the field equations in the mean field approximation for the hedgehog baryon state with different sets of model parameters. A new parametrization which well describe the nucleon properties has been introduced and compared with experimental data.
Chiral symmetry breaking in lattice QED model with fermion brane
Shintani, E
2012-01-01
We propose a novel approach of spontaneous chiral symmetry breaking at near zero temperature in 4 dimensional QED model with 3+1 dimensional fermion brane using Hybrid Monte Carlo simulation. We consider an anisotropic QED coupling in non-compact QED action with the manifest gauge invariant interaction and fermi-velocity which is less than speed of light. This model allows for the scaling study at low temperature and strong coupling region with reduced computational cost. We compute the chiral condensate and its susceptibility with different coupling constant, velocity parameter and flavor number, and therefore obtain a compatible behavior with gap equation in broken phase. We also discuss about the comparison of Graphene model.
Physical properties of the chiral quantum baryon
It is presented an account to understand the quantum chiral baryon, which a stable chiral soliton with baryon number one obtained after first quantization by collective coordinates. Starting from the exact series solution to the non-linear sigma model with the hedge-hog configuration, the values of several physical quantities (mass, axial weak coupling, gyromagnetic ratios and radii) as a function of the order of Pade approximants used as approximanted representations of the solution, are calculated. It turns out that consistent results may be obtained, but a better approximation should be developed. (author)
Bubble and kink solitons in the φ6-model of nonlinear field theory
We have studied the φ6-model in the parameter domain A>1, with A being the relevant parameter of the model. For this case we have found localized soliton-like solutions: kinks and bubbles. The investigation of waves propagating through a stable vacuum shows that the sound velocity provides a rigid constraint for these oscillations to be stable or not. (orig.)
A chiral symmetric quark model without free quarks
A chirally symmetric quark model is presented which contrary to the Nambu Jona-Lasinio (NJL) model does not lead to the presence of free quarks. In the model a non-local effective interaction is used as a schematic parameterization of the quark antiquark scattering kernel. The non-locality can be interpreted as phenomenologically taking into account an infinite number of elementary scattering processes, like the sum of all multi-gluon exchange processes in the particle-particle channel. The basic Lagrangian of the interaction shares all global internal symmetries with QCD. In particular in the limit of vanishing current quark masses it is chirally symmetric. Starting from the non-local scattering kernel the solution of the Dyson-Schwinger equation and the Bethe-Salpeter equation leads to a consistent description of the dressed quark propagators with the mesonsa s quark-antiquark states. Like in the NJL-model chiral symmetry is spontaneously broken. Because of the non-locality of the interaction, however, in our model the quarks do not acquire a constant constituent mass but a four momentum dependent selfenergy. (orig.)
Trying to stabilize a soliton in the one-loop σ-model
The viability of a soliton in the one-loop σ-model in the presence of an omega meson is studied. The effective action is estimated in a mean field treatment and an approximate expression of the baryonic current is used. Renormalization is shown to be conveniently effected in the phase shift formalism, using the ζ-function method. The soliton is still found to be unstable. Next, we calculate the determinant coming from the bosonic fluctuations. It is found to be nearly saturated by the first term in the derivative expansion. It is confirmed that this determinant cannot stabilize a soliton against scaling and that it is dominated at short distances by the fermionic determinant. Finally, effective actions with an explicit momentum cutoff are considered. The mass can have a well defined minimum in this case, but this result is shown to depend crucially on the smoothness of the cutoff function
Microscopically constrained mean-field models from chiral nuclear thermodynamics
Rrapaj, Ermal; Roggero, Alessandro; Holt, Jeremy W.
2016-06-01
We explore the use of mean-field models to approximate microscopic nuclear equations of state derived from chiral effective field theory across the densities and temperatures relevant for simulating astrophysical phenomena such as core-collapse supernovae and binary neutron star mergers. We consider both relativistic mean-field theory with scalar and vector meson exchange as well as energy density functionals based on Skyrme phenomenology and compare to thermodynamic equations of state derived from chiral two- and three-nucleon forces in many-body perturbation theory. Quantum Monte Carlo simulations of symmetric nuclear matter and pure neutron matter are used to determine the density regimes in which perturbation theory with chiral nuclear forces is valid. Within the theoretical uncertainties associated with the many-body methods, we find that select mean-field models describe well microscopic nuclear thermodynamics. As an additional consistency requirement, we study as well the single-particle properties of nucleons in a hot/dense environment, which affect e.g., charged-current weak reactions in neutron-rich matter. The identified mean-field models can be used across a larger range of densities and temperatures in astrophysical simulations than more computationally expensive microscopic models.
ND^(*) and NB^(*) interactions in a chiral quark model
Yang, Dan; Zhang, Dan
2015-01-01
ND and ND^* interactions become a hot topic after the observation of new charmed hadrons \\Sigma_c(2800) and \\Lambda_c(2940)^+. In this letter, we have preliminary investigated S-wave ND and ND^* interactions with possible quantum numbers in the chiral SU(3) quark model and the extended chiral SU(3) quark model by solving the resonating group method equation. The numerical results show that the interactions between N and D or N and D^* are both attractive, which are mainly from \\sigma exchanges between light quarks. Further bound-state studies indicate the attractions are strong enough to form ND or ND^* molecules, except for (ND)_{J=3/2} and (ND^*)_{J=3/2} in the chiral SU(3) quark model. In consequence ND system with J=1/2 and ND^* system with J=3/2 in the extended SU(3) quark model could correspond to the observed \\Sigma_c(2800) and \\Lambda_c(2940)^+, respectively. Naturally, the same method can be applied to research NB and NB^* interactions, and similar conclusions obtained, i.e. NB and NB^* attractive fo...
An Anderson-like model of the QCD chiral transition
Giordano, Matteo; Pittler, Ferenc
2016-01-01
We study the problems of chiral symmetry breaking and eigenmode localisation in finite-temperature QCD by looking at the lattice Dirac operator as a random Hamiltonian. We recast the staggered Dirac operator into an unconventional three-dimensional Anderson Hamiltonian ("Dirac-Anderson Hamiltonian") carrying internal degrees of freedom, with disorder provided by the fluctuations of the gauge links. In this framework, we identify the features relevant to chiral symmetry restoration and localisation of the low-lying Dirac eigenmodes in the ordering of the local Polyakov lines, and in the related correlation between spatial links across time slices, thus tying the two phenomena to the deconfinement transition. We then build a toy model based on QCD and on the Dirac-Anderson approach, replacing the Polyakov lines with spin variables and simplifying the dynamics of the spatial gauge links, but preserving the above-mentioned relevant dynamical features. Our toy model successfully reproduces the main features of the...
Self-Dual Chern-Simons Solitons and Generalized Heisenberg Ferromagnet Models
Oh, P; Oh, Phillial
1996-01-01
We consider the (2+1)-dimensional gauged Heisenberg ferromagnet model coupled with the Chern-Simons gauge fields. Self-dual Chern-Simons solitons, the static zero energy solution saturating Bogomol'nyi bounds, are shown to exist when the generalized spin variable is valued in the Hermitian symmetric spaces G/H. By gauging the maximal torus subgroup of H, we obtain self-dual solitons which satisfy vortex-type nonlinear equations thereby extending the two dimensional instantons in a nontrivial way. An explicit example for the CP(N) case is given.
Continuum model for chiral induced spin selectivity in helical molecules
Medina, Ernesto [Centro de Física, Instituto Venezolano de Investigaciones Científicas, 21827, Caracas 1020 A (Venezuela, Bolivarian Republic of); Groupe de Physique Statistique, Institut Jean Lamour, Université de Lorraine, 54506 Vandoeuvre-les-Nancy Cedex (France); Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287 (United States); González-Arraga, Luis A. [IMDEA Nanoscience, Cantoblanco, 28049 Madrid (Spain); Finkelstein-Shapiro, Daniel; Mujica, Vladimiro [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287 (United States); Berche, Bertrand [Centro de Física, Instituto Venezolano de Investigaciones Científicas, 21827, Caracas 1020 A (Venezuela, Bolivarian Republic of); Groupe de Physique Statistique, Institut Jean Lamour, Université de Lorraine, 54506 Vandoeuvre-les-Nancy Cedex (France)
2015-05-21
A minimal model is exactly solved for electron spin transport on a helix. Electron transport is assumed to be supported by well oriented p{sub z} type orbitals on base molecules forming a staircase of definite chirality. In a tight binding interpretation, the spin-orbit coupling (SOC) opens up an effective π{sub z} − π{sub z} coupling via interbase p{sub x,y} − p{sub z} hopping, introducing spin coupled transport. The resulting continuum model spectrum shows two Kramers doublet transport channels with a gap proportional to the SOC. Each doubly degenerate channel satisfies time reversal symmetry; nevertheless, a bias chooses a transport direction and thus selects for spin orientation. The model predicts (i) which spin orientation is selected depending on chirality and bias, (ii) changes in spin preference as a function of input Fermi level and (iii) back-scattering suppression protected by the SO gap. We compute the spin current with a definite helicity and find it to be proportional to the torsion of the chiral structure and the non-adiabatic Aharonov-Anandan phase. To describe room temperature transport, we assume that the total transmission is the result of a product of coherent steps.
Chiral-Symmetric Technicolor with Standard Model Higgs boson
Pasechnik, Roman; Kuksa, Vladimir; Vereshkov, Grigory
2013-01-01
Most of the traditional Technicolor-based models are known to be in a strong tension with the electroweak precision data. We show that this serious issue is naturally cured in strongly coupled sectors with chiral-symmetric vector-like gauge interactions in the framework of gauged linear sigma model. We discuss possible phenomenological implications of such non-standard chiral-symmetric Technicolor scenario in its simplest formulation preserving the standard Higgs mechanism and (possibly) elementary Higgs boson of the Standard Model (SM). For this purpose, we assume the existence of an extra technifermion sector confined under extra SU(3)_TC at the energy scales reachable at the LHC, Lambda_TC ~ 0.1-1 TeV, and interacting with the SM gauge bosons in a chiral-symmetric (vector-like) way. In the framework of this scenario, the SM Higgs vev acquires natural interpretation in terms of the condensate of technifermions in confinement. We study the influence of the lowest lying composite physical states, namely, tech...
Soliton Fay identities: I. Dark soliton case
We derive a set of bilinear identities for the determinants of the matrices that have been used to construct dark soliton solutions for various models. To give examples of the application of the obtained identities, we present soliton solutions for the equations describing multidimensional quadrilateral lattices, Darboux equations, and multidimensional multicomponent systems of the nonlinear Schrödinger type. (paper)
Soliton fay identities: II. Bright soliton case
We present a set of bilinear matrix identities that generalize the ones that have been used to construct the bright soliton solutions for various models. As an example of an application of these identities, we present a simple derivation of the N-bright soliton solutions for the Ablowitz–Ladik hierarchy. (paper)
Soliton Fay identities. I. Dark soliton case
Vekslerchik, V. E.
2014-01-01
We derive a set of bilinear identities for the determinants of the matrices that have been used to construct the dark soliton solutions for various models. To give examples of the application of the obtained identities we present soliton solutions for the equations describing multidimensional quadrilateral lattices, Darboux equations and multidimensional multicomponent systems of the nonlinear Schrodinger type.
Soliton Fay identities. II. Bright soliton case
Vekslerchik, V. E.
2015-01-01
We present a set of bilinear matrix identities that generalize the ones that have been used to construct the bright soliton solutions for various models. As an example of an application of these identities, we present a simple derivation of the N-bright soliton solutions for the Ablowitz-Ladik hierarchy.
Scalar mesons in a chiral quark model with glueball
Ground-state scalar isoscalar mesons and a scalar glueball are described in a U(3)xU(3) chiral quark model of the Nambu-Jona-Lasinio (NJL) type with 't Hooft interaction. The latter interaction produces singlet-octet mixing in the scalar and pseudoscalar sectors. The glueball is introduced into the effective meson Lagrangian as a dilaton on the basis of scale invariance. The mixing of the glueball with scalar isoscalar quarkonia and amplitudes of their decays into two pseudoscalar mesons are shown to be proportional to current quark masses, vanishing in the chiral limit. Mass spectra of the scalar mesons and the glueball and their main modes of strong decay are described
A class of integrable expanding model for the coupled AKNS-Kaup-Newell soliton hierarchy
Yang Hong-Xiang; Xu Xi-Xiang
2005-01-01
An isospectral problem is established by means of a sub-algebra of loop Lie algebra (A)1, from which the coupled AKNS-Kaup-Newell soliton hierarchy is derived. Subsequently, the integrable expanding model, i.e. integrable coupling,is constructed through enlarging the corresponding loop algebra into the loop Lie algebra (A)2.
Quadratic solitons as nonlocal solitons
Nikolov, Nikola Ivanov; Neshev, D.; Bang, Ole; Królikowski, W.
2003-01-01
We show that quadratic solitons are equivalent to solitons of a nonlocal Kerr medium. This provides new physical insight into the properties of quadratic solitons, often believed to be equivalent to solitons of an effective saturable Kerr medium. The nonlocal analogy also allows for novel analytical solutions and the prediction of novel bound states of quadratic solitons.
Quadratic solitons as nonlocal solitons
Nikolov, Nikola Ivanov; Neshev, D.; Bang, Ole;
2003-01-01
We show that quadratic solitons are equivalent to solitons of a nonlocal Kerr medium. This provides new physical insight into the properties of quadratic solitons, often believed to be equivalent to solitons of an effective saturable Kerr medium. The nonlocal analogy also allows for analytical...... solutions and the prediction of bound states of quadratic solitons....
K^- nuclear potentials from in-medium chirally motivated models
Cieplý, A; Gal, A; Gazda, D; Mareš, J
2011-01-01
A self consistent scheme for constructing K^- nuclear optical potentials from subthreshold in-medium Kbar-N s-wave scattering amplitudes is presented and applied to analysis of kaonic atoms data and to calculations of K^- quasibound nuclear states. The amplitudes are taken from a chirally motivated meson-baryon coupled-channel model, both at the Tomozawa-Weinberg leading order and at the next to leading order. Typical kaonic atoms potentials are characterized by a real part -Re V(K^-;chiral)=(85+/-5) MeV at nuclear matter density, in contrast to half this depth obtained in some derivations based on in-medium Kbar-N threshold amplitudes. The moderate agreement with data is much improved by adding complex rho- and rho^2-dependent phenomenological terms, found to be dominated by rho^2 contributions that could represent Kbar-NN -> YN absorption and dispersion, outside the scope of meson-baryon chiral models. Depths of the real potentials are then near 180 MeV. The effects of p-wave interactions are studied and fo...
Hyun, Chang Ho; Lee, Hee-Jung
2016-01-01
We investigate the parity-violating pion-nucleon-nucleon coupling constant $h^1_{\\pi NN}$, based on the chiral quark-soliton model. We employ an effective weak Hamiltonian that takes into account the next-to-leading order corrections from QCD to the weak interactions at the quark level. Using the gradient expansion, we derive the leading-order effective weak chiral Lagrangian with the low-energy constants determined. The effective weak chiral Lagrangian is incorporated in the chiral quark-soliton model to calculate the parity-violating $\\pi NN$ constant $h^1_{\\pi NN}$. We obtain a value of about $10^{-7}$ at the leading order. The corrections from the next-to-leading order reduce the leading order result by about 20~\\%.
Deep inelastic structure functions in the chiral bag model
We calculate the structure functions for deep inelastic scattering on baryons in the cavity approximation to the chiral bag model. The behavior of these structure functions is analyzed in the Bjorken limit. We conclude that scaling is satisfied, but not Regge behavior. A trivial extension as a parton model can be achieved by introducing the structure function for the pion in a convolution picture. In this extended version of the model not only scaling but also Regge behavior is satisfied. Conclusions are drawn from the comparison of our results with experimental data. (orig.)
Pion Effect of Nuclear Matter in a Chiral Sigma Model
HU Jin-niu; Y.Ogawa; H.Toki; A.Hosaka; SHEN Hong
2009-01-01
We develop a new framework for the study of the nuclear matter based on the linear sigma model.We introduce a completely new viewpoint on the treatment of the nuclear matter with the inclusion of the pion.We extend the relativistic chiral mean field model by using the similar method in the tensor optimized shell model.We also regulate the pion-nucleon interaction by considering the form-factor and short range repulsion effects.We obtain the equation of state of nuclear matter and study the importance of the pion effect.
Moduli stabilization in chiral type IIB orientifold models with fluxes
We consider type IIB orientifold models on Calabi-Yau spaces with three-form G-flux turned on. These fluxes freeze some of the complex structure moduli and the complex dilaton via an F-term scalar potential. By introducing pairs of D9-D9-bar branes with Abelian magnetic fluxes it is possible to freeze also some of the Kaehler moduli via a D-term potential. Moreover, such magnetic fluxes in general lead to chiral fermions, which make them interesting for string model-building. These issues are demonstrated in a simple toy model based on a Z2xZ2' orbifold
Deep inelastic structure functions in the chiral bag model
Sanjose, V. (Valencia Univ. (Spain). Dept. de Didactica de las Ciencias Experimentales); Vento, V. (Valencia Univ. (Spain). Dept. de Fisica Teorica; Centro Mixto CSIC/Valencia Univ., Valencia (Spain). Inst. de Fisica Corpuscular)
1989-10-02
We calculate the structure functions for deep inelastic scattering on baryons in the cavity approximation to the chiral bag model. The behavior of these structure functions is analyzed in the Bjorken limit. We conclude that scaling is satisfied, but not Regge behavior. A trivial extension as a parton model can be achieved by introducing the structure function for the pion in a convolution picture. In this extended version of the model not only scaling but also Regge behavior is satisfied. Conclusions are drawn from the comparison of our results with experimental data. (orig.).
Conceptual Foundations of Soliton Versus Particle Dualities Toward a Topological Model for Matter
Kouneiher, Joseph
2016-06-01
The idea that fermions could be solitons was actually confirmed in theoretical models in 1975 in the case when the space-time is two-dimensional and with the sine-Gordon model. More precisely S. Coleman showed that two different classical models end up describing the same fermions particle, when the quantum theory is constructed. But in one model the fermion is a quantum excitation of the field and in the other model the particle is a soliton. Hence both points of view can be reconciliated.The principal aim in this paper is to exhibit a solutions of topological type for the fermions in the wave zone, where the equations of motion are non-linear field equations, i.e. using a model generalizing sine- Gordon model to four dimensions, and describe the solutions for linear and circular polarized waves. In other words, the paper treat fermions as topological excitations of a bosonic field.
Scattering of Topological Solitons on Barriers and Holes of Deformed Sine-Gordon Models
Al-Alawi, Jassem H
2008-01-01
We study scattering properties of topological solitons in two classes of models, which are generalizations of the Sine-Gordon model and which have recently been proposed by Bazeia et al. These two classes of models depend on an integer parameter n which, when n=2(for the first class) and n=1 (for the second class), reduce to the Sine-Gordon model. We take the soliton solutions of these models (generalizations of the 'kink' solution of the Sine-Gordon model) and consider their scattering on potential holes and barriers. We present our results for n=1,...6. We find that, like in the Sine Gordon models, the scattering on the barrier is very elastic while the scattering on the hole is inelastic and can at times, lead to a reflection. We discuss the dependence of our results on n and find that the critical velocity for the transmission through the hole is lowest for n=3.
Soft Matrix Elements in Non-local Chiral Quark Model
Kotko, Piotr
2009-01-01
Using non-local chiral quark model and currents satisfying Ward-Takahashi identities we analyze Distribution Amplitudes (DA) of photon and pion-to-photon Transition Distribution Amplitudes (TDA) in the low energy regime. Photon DA's are calculated analytically up to twist-4 and reveal several interesting features of photon structure. TDA's calculated in the present model satisfy polynomiality condition. Normalization of vector TDA is fixed by the axial anomaly. We also compute relevant form factors and compare them with existing data. Axial form factor turns out to be much lower then the vector one, what indeed is seen in the experimental data.
Relativistic Chiral Mean Field Model for Finite Nuclei
Ogawa, Yoko; Toki, Hiroshi; Tamenaga, Setsuo; Haga, Akihiro
2012-01-01
We present a relativistic chiral mean field (RCMF) model, which is a method for the proper treatment of pion-exchange interaction in the nuclear many-body problem. There the dominant term of the pionic correlation is expressed in two-particle two-hole (2p-2h) states with particle-holes having pionic quantum number, J^{pi}. The charge-and-parity-projected relativistic mean field (CPPRMF) model developed so far treats surface properties of pionic correlation in 2p-2h states with J^{pi} = 0^{-} ...
On the chiral phase transition in the linear sigma model
The Cornwall- Jackiw-Tomboulis (CJT) effective action for composite operators at finite temperature is used to investigate the chiral phase transition within the framework of the linear sigma model as the low-energy effective model of quantum chromodynamics (QCD). A new renormalization prescription for the CJT effective action in the Hartree-Fock (HF) approximation is proposed. A numerical study, which incorporates both thermal and quantum effect, shows that in this approximation the phase transition is of first order. However, taking into account the higher-loop diagrams contribution the order of phase transition is unchanged. (author)
The MIT bag was one of the earliest and most successful models of QCD, imposing confinement and including perturbative gluon interactions. An evolution of the MIT bag came with the introduction of the chiral and cloudy bags, which treat pions as elementary particles. As a model of QCD, the soliton model proposed by Friedberg and Lee is particularly attractive. It is based on a covariant field theory and is sufficiently general so that, for certain limiting cases of the adjustable parameters, it can describe either the MIT or SLAC (string) bags. The confinement mechanism appears as a dynamic field. This allows non-static processes, such as bag oscillations and bag collisions, to be calculated utilizing the well-developed techniques of nuclear many-body theory. The utilization of the model for calculating dynamical processes is discussed. 14 references
Microscopic spectral density in random matrix models for chiral and diquark condensation
We examine random matrix models of QCD which are capable of supporting both chiral and diquark condensation. A numerical study of the spectral densities near zero virtuality shows that the introduction of color in the interactions does not alter the one-body results imposed by chiral symmetry. A model with three colors has the spectral density predicted for the chiral ensemble with a Dyson index β=2; a pseudoreal model with two colors exhibits the spectral density of the chiral ensemble with β=1
Quasi-integrability in the modified defocusing non-linear Schr\\"odinger model and dark solitons
Blas, H
2015-01-01
The concept of quasi-integrability has been examined in the context of deformations of the defocusing non-linear Schr\\"odinger model (NLS). Our results show that the quasi-integrability concept, recently discussed in the context of deformations of the sine-Gordon, Bullough-Dodd and focusing NLS models, holds for the modified defocusing NLS model with dark soliton solutions and it exhibits the new feature of an infinite sequence of alternating conserved and asymptotically conserved charges. For the special case of two dark soliton solutions, where the field components are eigenstates of a space-reflection symmetry, the first four and the sequence of even order charges are exactly conserved in the scattering process of the solitons. Such results are obtained through analytical and numerical methods, and employ adaptations of algebraic techniques used in integrable field theories. We perform extensive numerical simulations and consider the scattering of dark solitons for the cubic-quintic NLS model with potentia...
Chiral models of low energy QCD
Two processes may be distinguished when a hadron propagates in a dense baryonic medium. The polarization of the medium and the change in the quark structure of the hadron. The polarization of the medium is better described in terms of colorless mesons and nucleons while the intrinsic change of the hadron is better described by quark models. It is shown how to couple the two processes. The scaling of effective Lagrangians, is related to changes in the quark constituent masses, based on the QCD scale anomaly. (author) 62 refs
NN Scattering Phase Shifts in a Chiral Constituent Quark Model
Bartz, D.; Stancu, Fl
2000-01-01
We study the nucleon-nucleon interaction within a chiral constituent quark model which reproduces succesfully the baryon spectra. We calculate the 3S1 and 1S0 phase shifts by using the resonating group method. They clearly indicate the presence of a strong repulsive interaction at short distance, due to the spin-flavor symmetry of the quark-quark interaction and of the quark interchange between the two interacting nucleons. A sigma-exchange quark-quark interaction, providing a medium-range at...
One loop quantum fluctuations to the energy of the non-topological soliton in Friedberg-Lee model
Shu, Song
2016-01-01
I have used a practical method to calculate the one-loop quantum correction to the energy of the non-topological soliton in Friedberg-Lee model. The quantum effects which come from the quarks of the Dirac sea scattering with the soliton bag are calculated by a summation of the discrete and continuum energy spectrum of the Dirac equation in the background field of soliton. The phase shift of the continuum spectrum is numerically calculated in an efficient way and all the divergences are removed by the same renormalization procedure.
Dualities in the d=2 asymmetric chiral field sigma models
Continuous dual symmetry of equations of asymmetric chiral field (ACF) in d=2 (equations of non-linear σ-models with ambiguous effect) and realization of duality transformations in explicit geometrical language of Cartran form is disclosed. Connection of this symmetry with ACF integrability is clarified. Both simple and supersymmetrical cases are considered. Notions of dual algebra and dual σ-model are introduced, their significance for understanding classical and quantum structure d=2 of ACF models is revealed. It is shown, in particular, that transition to points of infrared ACF stability can be described purely algebraically as constraction of dual algebra bringing about the fact that space-factor of the corresponding dual σ-model becomes plane. Equations of asymmetrical n vector-field model are analyzed from the similar view point. The Cartran form method permits to state that classical dynamics of this model is trivial
Finite-temperature corrections in the dilated chiral quark model
We calculate the finite-temperature corrections in the dilated chiral quark model using the effective potential formalism. Assuming that the dilaton limit is applicable at some short length scale, we interpret the results to represent the behavior of hadrons in dense and hot matter. We obtain the scaling law, fπ(T)/fπ = mQ(T)/mQ ≅ mσ(T)/mσwhile we argue, using PCAC, that pion mass does not scale within the temperature range involved in our Lagrangian. It is found that the hadron masses and the pion decay constant drop faster with temperature in the dilated chiral quark model than in the conventional linear sigma model that does not take into account the QCD scale anomaly. We attribute the difference in scaling in heat bath to the effect of baryonic medium on thermal properties of the hadrons. Our finding would imply that the AGS experiments (dense and hot matter) and the RHIC experiments (hot and dilute matter) will ''see'' different hadron properties in the hadronization exit phase
An Effective Chiral Meson Lagrangian at O(p6) from the NJL Model
In this work we present a strong chiral meson Lagrangian up to and including O(p6) in the momentum expansion. It is derived from the Nambu-Jona-Lasinio (NJL) model using the heat-kernel method. Identities related to the properties of covariant derivatives of the chiral matrix U as well as field transformations have been used to predict the chiral coefficients of a minimal set of linearly independent terms. 16 refs
Fluctuations and the Phase Transition in a Chiral Model with Polyakov Loops
Sasaki, C.; Friman, B.; Redlich, K.
2007-01-01
We explore the NJL model with Polyakov loops for a system of three colors and two flavors within the mean-field approximation, where both chiral symmetry and confinement are taken into account. We focus on the phase structure of the model and study the chiral and Polyakov loop susceptibilities.
Relativistic Quark Model Calculation of the l1, l2 Coefficients of the Chiral Lagrangian
Llanes-Estrada, Felipe J.; Bicudo, Pedro
2002-01-01
We briefly report on a relativistic quark model scheme to calculate the O(P^4) pion-pion vertex in the planar approximation and in the chiral limit. The calculation is reduced to the solution of simple integral equations (Bethe-Salpeter like) by an effective use of chiral Ward Identities. Specific model computations are provided.
Baryon resonances in a chiral confining model, 1
Umino, Y
1998-01-01
In this two part series a chiral confining model of baryons is used to describe low--lying negative parity resonances $N^*$, $\\Delta^*$, $\\Lambda^*$ and $\\Sigma^*$ in the mean field approximation. A physical baryon in this model consists of interacting valence quarks, mesons and a color and chiral singlet hybrid field coexisting inside a dynamically generated confining region. This first paper presents the quark contribution to the masses and wave functions of negative parity baryons calculated with an effective spin--isospin dependent instanton induced interaction. It does not include meson exchanges between quarks. The three--quark wave functions are used to calculate meson--excited baryon vertex functions to lowest order in meson--quark coupling. When the baryons are on mass--shell each of these vertex functions is a product of a coupling constant and a form factor. As examples, quark contributions to $N^*$ hadronic form factors as well as axial coupling constants are extracted from the vertex functions an...
We construct a special type of quantum soliton solutions for quantized affine Toda models. The elements of the principal Heisenberg subalgebra in the affinised quantum Lie algebra are found. Their eigenoperators inside the quantized universal enveloping algebra for an affine Lie algebra are constructed to generate quantum soliton solutions
An energy conserving finite-difference model of Maxwell's equations for soliton propagation
Bachiri, H; Vázquez, L
1997-01-01
We present an energy conserving leap-frog finite-difference scheme for the nonlinear Maxwell's equations investigated by Hile and Kath [C.V.Hile and W.L.Kath, J.Opt.Soc.Am.B13, 1135 (96)]. The model describes one-dimensional scalar optical soliton propagation in polarization preserving nonlinear dispersive media. The existence of a discrete analog of the underlying continuous energy conservation law plays a central role in the global accuracy of the scheme and a proof of its generalized nonlinear stability using energy methods is given. Numerical simulations of initial fundamental, second and third-order hyperbolic secant soliton pulses of fixed spatial full width at half peak intensity containing as few as 4 and 8 optical carrier wavelengths, confirm the stability, accuracy and efficiency of the algorithm. The effect of a retarded nonlinear response time of the media modeling Raman scattering is under current investigation in this context.