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In this work we develop a new version of the fuzzy bag model. The new feature is the inclusion of energy–momentum conservation. This turns the model into a "real" bag model, as opposed to a relativistic potential model. One immediate consequence is that the bag constant B will acquire a radial dependence, B = B(r), whose functional form can be completely fixed without any arbitrariness. Such a feature is of importance in the study of neutron stars, where a radial dependence of B is usually put in by hand. The parameters of the model are found by fitting the masses of the baryon octet. We include center-of-mass, one-gluon exchange and pion exchange corrections for these masses.
We evaluate the fermionic Casimir effect associated with a massive fermion confined within a planar (d + 1)-dimensional slab-bag, on which MIT bag model boundary conditions of the standard type, along a single spatial direction, are imposed. A simple and effective method for adding up the zero-point energy eigenvalues, corresponding to a quantum field under the influence of arbitrary boundary conditions, imposed on the field on flat surfaces perpendicular to a chosen spatial direction, is proposed. Using this procedure, an analytic result is obtained, from which small and large fermion mass limits, valid for an arbitrary number of dimensions, are derived. They match some known results in particular cases. The method can be easily extended to other configurations.
A general coordinate invariant theory is constructed where confinement of gauge fields and gauge dynamics in general is governed by the spontaneous symmetry breaking (s.s.b.) of scale invariance. The model uses two measures of integration in the action, the standard where g is the determinant of the metric and another measure Φ independent of the metric. To implement scale invariance, a dilaton field is introduced. Using the first-order formalism, curvature (ΦR and
) terms, gauge field term (
and
) and dilaton kinetic terms are introduced in a conformally invariant way. Exponential potentials for the dilaton break down (softly) the conformal invariance down to global scale invariance, which also suffers s.s.b. after integrating the equations of motion. The model has a well-defined flat space limit. As a result of the s.s.b. of scale invariance phases with different vacuum energy density appear. Inside the bags, that is in the regions of larger vacuum energy density, the gauge dynamics is normal, that is nonconfining, while for the region of smaller vacuum energy density, the gauge field dynamics is confining. Likewise, the dynamics of scalars, like would be Goldstone bosons, is suppressed inside the bags.
It is known that gravitational and electromagnetic fields of an electron are described by the ultra-extreme Kerr-Newman (KN) black hole solution with extremely high spin/mass ratio. This solution is singular and has a topological defect, the Kerr singular ring, which may be regularized by introducing the solitonic source based on the Higgs mechanism of symmetry breaking. The source represents a domain wall bubble interpolating between the flat region inside the bubble and external KN solution. It was shown recently that the source represents a supersymmetric bag model, and its structure is unambiguously determined by Bogomolnyi equations. The Dirac equation is embedded inside the bag consistently with twistor structure of the Kerr geometry, and acquires the mass from the Yukawa coupling with Higgs field. The KN bag turns out to be flexible, and for parameters of an electron, it takes the form of very thin disk with a circular string placed along sharp boundary of the disk. Excitation of this string by a traveling wave creates a circulating singular pole, indicating that the bag-like source of KN solution unifies the dressed and point-like electron in a single bag-string-quark system.
We construct models where initial and boundary conditions can be found from the fundamental rules of physics, without the need to assume them, they will be derived from the action principle. Those constraints are established from physical viewpoint, and it is not in the form of Lagrange multipliers. We show some examples from the past and some new examples that can be useful, where constraint can be obtained from the action principle. Those actions represent physical models. We show that it is possible to use our rule to get those constraints directly.
In this work we develop an effective formalism for nuclear matter based on the fuzzy bag model. The main objective of our study is to discuss the feasibility of using the fuzzy bag model to describe nuclear matter properties. The physical system is described in our approach by an internal energy function, which has a free term, corresponding to a free Fermi gas, and an interacting one. In the interacting part, pion exchange is taken into account via an effective potential. To avoid superposition of nucleons, we introduce an exclusion volume à la Van der Waals. The internal energy function depends on the nuclear matter density and also on a parameter which will determine the expected volume of a nucleon in matter. We then obtain results for the binding energy per nucleon for the symmetric nuclear matter and for neutron matter, as well as the equation of state within this model. We then determine the mass of neutron stars in hydrostatic equilibrium, using the TOV equations. In spite of utilizing a treatment that is still very preliminary, our results show the feasibility of using this treatment to describe nuclear matter properties.
Well known weakness of gravity in particle physics is an illusion caused by underestimation of the role of spin in gravity. Relativistic rotation is inseparable from spin, which for elementary particles is extremely high and exceeds mass on 20–22 orders (in units c=G=m=ℏ=1). Such a huge spin generates frame-dragging that distorts space much stronger than mass, and effective scale of gravitational interaction is shifted from Planck to Compton distances. We show that compatibility between gravity and quantum theory can be achieved without modifications of Einstein–Maxwell equations, by coupling to a supersymmetric Higgs model of symmetry breaking and forming a nonperturbative super-bag solution, which generates a gravity-free Compton zone necessary for consistent work of quantum theory. Super-bag is naturally upgraded to Wess–Zumino supersymmetric QED model, forming a bridge to perturbative formalism of conventional QED.
The minisuperspace model in 3+d spatial dimensions with matter described by the bag model is considered with the aim of estimating the probability of creation of compactified extra dimensions in nuclear collisions. The amplitude of transition from three- to (3+d)-dimensional space has been calculated both in the case of completely confined matter, when the contribution of radiation is ignored, and in the case of radiation domination, when the bag constant is negligible. It turns out that the number of additional dimensions is limited in the first regime, while it is infinite in the second one. It is shown that the probability of creation of extra dimensions is finite in the both regimes.
The modified versions of the bag model equation of state (EoS) are considered. They are constructed to satisfy the main qualitative features observed for the quark–gluon plasma EoS in the lattice QCD calculations. A quantitative comparison with the lattice results at high temperatures T are done in the SU(3) gluodynamics and in the full QCD with dynamical quarks. Our analysis advocates a negative value of the bag constant B.
We consider the question of bags and confinement in the framework of a theory which uses two volume elements and Φd4x, where Φ is a metric independent density. For scale invariance a dilaton field Φ is considered. Using the first order formalism, curvature (ΦR and
) terms, gauge field term (
and
) and dilaton kinetic terms are introduced in a conformally invariant way. Exponential potentials for the dilaton break down (softly) the conformal invariance down to global scale invariance, which also suffers s.s.b. after integrating the equations of motion. The model has a well defined flat space limit. As a result of the s.s.b. of scale invariance phases with different vacuum energy density appear. Inside the bags the gauge dynamics is normal, that is non confining, while for the outside, the gauge field dynamics is confining.
Inspired by various astrophysical phenomenons, it is suggested that pulsar-like compact stars are comprised entirely of strangeons (quark-clusters with three-light-flavor symmetry) and a small amount of electrons. In order to better constrain the properties of strangeon stars, we propose a linked bag model to describe the condensed matter by the strong interaction (i.e., strong condensed matter) in both 2-flavored (nucleons) and 3-flavored (hyperons, strangeons, etc.) scenarios. The model parameters are calibrated to reproduce the saturation properties of nuclear matter, which are later applied to hyperon matter and strangeon matter. Compared with baryon matter, the derived energy per baryon of strangeon matter is reduced if the strangeon carries a large number of valence quarks, which stiffens the equation of state and consequently increases the maximum mass of strangeon stars. In a large parameter space, the maximum mass and tidal deformability of strangeon stars predicted by the linked bag model are consistent with the current astrophysical constraints. It is found that the maximum mass of strangeon stars can be as large as ∼2.5M⊙, while the tidal deformability of a 1.4M⊙ strangeon star lies in the range of 180≲Λ1.4≲340.
Standard model has to be generalized to a “New Physics” beyond the Standard Model. Main problem is the lack of consistency SM with gravity. We analyse Kerr-Newman spinning particle which is consistent with gravity by nature and, contrary to opinion that gravity conflicts with quantum theory, we obtain that spinning Kerr’s gravity collaborates with quantum theory in the process of formation of spinning particle. The most dramatic is the shift of the fundamental scale from Planck to Compton distances.
Based on the density-dependent relativistic Hartree-Fock theory (DDRHF) for hadronic matter, the properties of neutron stars have been studied and compared with the results from the density-dependent relativistic mean field theory (DDRMF). Though similar equations of state are obtained, DDRHF calculations give larger fractions of proton, electron and muon at high baryon density for neutron star matter than the ones from DDRMF. The maximum masses of neutron stars lie between 2.3 M⊙ and 2.5 M⊙, and the corresponding radii between 11.7 km and 12.5 km. In addition, the phase transition from hadronic matter to quark matter in neutron stars is studied by using the MIT bag model for the quark phase. The transition is studied in both Gibbs and Maxwell constructions.
Gravitational and electromagnetic (EM) field of the Dirac electron is described by an ultra-extreme Kerr-Newman (KN) black hole (BH) solution which has the naked singular ring and two-sheeted topology. This space is regulated by the formation of a solitonic source which shares much in common with the known MIT- and SLAC-bag models, but has the important advantage, of being in accordance with gravitational and electromagnetic field of the external KN solution. The used field model is supersymmetric LG model based on three chiral fields forming a domain wall bubble interpolating between the external exact KN solution and a flat supersymmetric core, which regulates singular zone of the Kerr-Newman solution. We reduce Hamiltonian to a Bogomolnyi form and obtain the regular BPS-saturated solution as an oscillon with quantized angular momentum. The main features of the soliton indicate its similarity to the bag models.
It is known that ultra-extreme Kerr-Newman (KN) solution (a >> m) produces the gravitational and EM fields of the electron and has a topological defect which may be regularized by a solitonic source, formed as a false-vacuum bubble filled by Higgs condensate in a supersymmetric superconducting state. Structure and stability of this source is determined by Bogomolnyi equations as a BPS-saturated soliton of the oscillon type. The Principal Null Congruences of the KN solution determine consistent embedding of the Dirac equation, which acquires the mass from the Higgs condensate inside the soliton, indicating that this soliton forms a bag model. Shape of this bag is unambiguously determined by BPS-bound. The bag turns out to be flexible and takes the form of a very thin disk, which is completed by a ring-string along its sharp boundary. The ring-string traveling waves generate extra deformations of the bag creating a circulating singular pole. Bag model of the KN source integrates the dressed and pointlike electron in a bag-string-quark system, which removes the conflict between the point-like electron of the Dirac theory and the required gravitational soliton model.
The ultra extreme Kerr-Newman (KN) solution(a = J/m >> m) produces the gravitational and EM fields of the electron. It has a naked singular ring – a topological defect which may be regularized by a solitonic source forming the pseudo-vacuum bubble filled by Higgs condensate in a supersymmetric superconducting state. Structure and stability of this source is determined by Bogomolnyi equations as a BPS-saturated soliton. The Principal Null Congruences of the KN solution determine consistent embedding of the Dirac equation, which acquires the mass from the Higgs condensate inside the soliton, indicating that this soliton forms a bag model. Shape of this bag is unambiguously determined by BPS-bound. The bag turns out to be flexible and takes the form of a very thin disk, which is completed by a ring-string along its sharp boundary. The ring-string traveling waves generate extra deformations of the bag creating a circulating singular pole. Bag model of the KN source integrates the dressed and pointlike electron in a bag-string-quark system, which removes the conflict between gravity and the point-like electron of the Dirac theory.