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Jorge Ananias Neto

Publications and source records attributed to Jorge Ananias Neto.

At least 55 records · Page 3Linked to original sources
arXiv2014

Quantum Gravitational Correction and MOND Theory in the Holographic Equipartition Scenario

In this paper, by using Verlinde's formalism and a modified Padmanabhan's prescription, we have obtained the lowest order quantum correction to the gravitational acceleration and MOND-type theory by considering a nonzero difference between the number of bits of the holographic screen and number of bits of the holographic screen that satisfy the equipartition theorem. We will also carry out a phase transition and critical phenomena analysis in MOND-type theory where critical exponents are obtained.

hep-th↗
arXiv2014

Holographic considerations on non-gaussian statistics and gravothermal catastrophe

In this paper we have derived the equipartition law of energy using Tsallis formalism and the Kaniadakis power law statistics in order to obtain a modified gravitational constant. We have applied this result in the gravothermal collapse phenomenon. We have discussed the equivalence between Tsallis and the Kaniadakis statistics in the context of Verlinde entropic formalism. In the same way we have analyzed negative heat capacities in the light of gravothermal catastrophe. The relative deviations of the modified gravitational constants are derived.

physics.gen-ph↗
arXiv2014

Dark energy models through nonextensive Tsallis' statistics

The accelerated expansion of the Universe is one of the greatest challenges of modern physics. One candidate to explain this phenomenon is a new field called dark energy. In this work we have used the Tsallis nonextensive statistical formulation of the Friedmann equation to explore the Barboza-Alcaniz and Chevalier-Polarski-Linder parametric dark energy models and the Wang-Meng and Dalal vacuum decay models. After that, we have discussed the observational tests and the constraints concerning the Tsallis nonextensive parameter.

gr-qc↗
arXiv2014

Tsallis' thermostatitics, MOND theory and holographic considerations on a Machian Universe

MOND theory explains the rotation curves of the galaxies. Verlinde's ideas establishes an entropic origin for gravitational forces and Tsallis principle generalizes the theory of Boltzman-Gibbs. In this work we have promoted a connection between these recent approaches, that at first sight seemed to have few or no points in common, using the Mach's principle as the background. In this way we have used Tsallis formalism to calculate the main parameters of the Machian Universe including the Hubble parameter and the age of the Universe. After that, we have also obtained a new value for the Tsallis parameter via Mach's principle. Using Verlinde's entropic gravity we have obtained new forms for MOND's well established ingredients. Finally, based on the relations between particles and bits obtained here, we have discussed the idea of bits entanglement in the holographic screen.

physics.gen-ph↗
arXiv2013

Duality and gauge invariance of noncommutative spacetime Podolsky electromagnetic theory

The interest in higher derivatives field theories has its origin mainly in their influence concerning the renormalization properties of physical models and to remove ultraviolet divergences. In this letter we have introduced the noncommutative (NC) version of the Podolsky theory and we investigated the effect of the noncommutativity over its original gauge invariance property. We have demonstrated precisely that the noncommutativity spoiled the gauge invariance of the original action. After that we have used the Noether dualization technique to obtain a dual and gauge invariant action. More than to obtain the NC Podolsky theory, we have another motivation in this work, which is to show that, although the introduction of noncommutativity spoils the gauge invariance, it is possible to recover this property using a standard dualization method which did not need any modification due to any NC effect in the original theory, by the way

hep-th↗
arXiv2013

Nonextensive statistics, entropic gravity and gravitational force in a non-integer dimensional space

Based on the connection between Tsallis nonextensive statistics and fractional dimensional space, in this work we have introduced, with the aid of Verlinde's formalism, the Newton constant in a fractal space as a function of the nonextensive constant. With this result we have constructed a curve that shows the direct relation between Tsallis nonextensive parameter and the dimension of this fractal space. We have demonstrated precisely that there are ambiguities between the results due to Verlinde's approach and the ones due to fractional calculus formalism. We have shown precisely that these ambiguities appear only for spaces with dimensions different from three. Hence, we believe that this is a result in favor of our three dimensional world.

hep-th↗
arXiv2013

Considerations on Gravity as an Entropic Force and Entangled States

Verlinde's ideas considered gravity as an emergent force originated from entropic concepts. This hypothesis generated a huge number of papers through the last recent years concerning classical and quantum approaches about the issue. In a recent paper Kobakhidze, using ultra-cold neutrons experiment, claimed that Verlinde's entropic gravity is not correct. In this letter, by considering the nonadditivity property of the holographic screen, where we assumed that the bits are entangled states, we showed that it is possible to confirm Verlinde's formalism.

hep-th↗
arXiv2013

New bounds for Tsallis parameter in a noncommutative phase-space entropic gravity and nonextensive Friedmann equations

In this paper, we have analyzed the nonextensive Tsallis statistical mechanics in the light of Verlinde's formalism. We have obtained, with the aid of a noncommutative phase-space entropic gravity, a new bound for Tsallis nonextensive (NE) parameter (TNP) that is clearly different from the ones present in the current literature. We derived the Friedmann equations in a NE scenario. We also obtained here a relation between the gravitational constant and the TNP.

hep-th↗
arXiv2011

Nonhomogeneous Cooling, Entropic Gravity and MOND Theory

In this paper, by using the holographic principle, a modified equipartition theorem where we assume that below a critical temperature the energy is not equally divided on all bits, and the Unruh temperature, we derive MOND theory and a modified Friedmann equation compatible with MOND theory. Furthermore, we rederive a modified Newton's law of gravitation by employing an adequate redefinition of the numbers of bits.

hep-th↗
arXiv2009

The Gauge Unfixing Formalism and the Solutions of the Dirac Bracket Commutators

We propose a systematic procedure that solves the Dirac bracket commutators. The method is based on the Gauge Unfixing formalism, a procedure that converts second class systems into first class ones without the enlargement of the original phase space variables. We verify that the gauge invariant variables satisfy the Dirac bracket when we strongly impose the discarded second class constraint. Thus, we can derive physical operators that satisfy the Dirac commutators. In order to illustrate our procedure, three second class constrained systems are considered. Firstly, the free particle on the two dimensional sphere is treated. The second case considered is the noncommutative free particle and the third is the doubly special relativity particle.

hep-th↗
arXiv2007

An improved Gauge Unfixing formalism and the Abelian Pure Chern Simons Theory

We propose a variant scheme of the Gauge Unfixing formalism which modifies directly the original phase space variables of a constrained system. These new variables are gauge invariant quantities. We apply our procedure in a mixed constrained system that is the Abelian Pure Chern Simons Theory where several gains are obtained. In particular, from the gauge invariant Hamiltonian and using the inverse Legendre transformation, we obtain the same initial Abelian Pure Chern Simons Lagrangian as the gauge invariant Lagrangian. This result shows that the gauge symmetry of the action is certainly preserved.

hep-th↗
arXiv2005

Removing the Wess Zumino fields in the BFFT formalism

In this paper we give some prescriptions in order to remove the Wess Zumino fields of the BFFT formalism and, consequently, we derive a gauge invariant system written only in terms of the original second class phase space variables. Here, the Wess Zumino fields are considered only as auxiliary variables that permit us to reveal the underlying symmetries present in a second class system. We apply our formalism in three important and illustrative constrained systems which are the Chern Simons Proca theory, the Abelian Proca model and the reduced SU(2) Skyrme model.

hep-th↗
arXiv2003

Gauging by Stückelberg field-shifting symmetry

We embed second class constrained systems by a formalism that combines concepts of the BFFT method and the unfixing gauge formalism. As a result, we obtain a gauge-invariant system where the introduction of the Wess-Zumino (WZ) field is essential. The initial phase-space variables are gauging with the introduction of the WZ field, a procedure that resembles the Stückelberg field- shifting formalism. In some cases, it is possible to eliminate the WZ field and, therefore, obtain an invariant system written only as a function of the original phase-space variables. We apply this formalism to important physical models: the reduced-SU(2) Skyrme model and the two dimensional chiral bosons field theory. In these systems, the gauge-invariant Hamiltonians are derived in a very simple way when compared with other usual formalisms.

hep-th↗
arXiv2000

The SU(2) Skyrme model and anomaly

The SU(2) Skyrme model,expanding in the collective coordinates variables, gives rise to second-class constraints. Recently this system was embedded in a more general Abelian gauge theory using the BFFT Hamiltonian method. In this work we quantize this gauge theory computing the Noether current anomaly using for this two different methods: an operatorial Dirac first class formalism and the non-local BV quantization coupled with the Fujikawa regularization procedure.

hep-th↗
arXiv1999

A proposal for a generalized canonical osp(1,2) quantization of dynamical systems with constraints

The aim of this paper is to consider a possibility of constructing for arbitrary dynamical systems with first-class constraints a generalized canonical quantization method based on the osp(1,2) supersymmetry principle. This proposal can be considered as a counterpart to the osp(1,2)-covariant Lagrangian quantization method introduced recently by Geyer, Lavrov and Mülsch. The gauge dependence of Green's functions is studied. It is shown that if the parameter m^2 of the osp(1,2) superalgebra is not equal to zero then the vacuum functional and S-matrix depend on the gauge. In the limit $m\to 0$ the gauge independence of vacuum functional and S - matrix are restored. The Ward identities related to the osp(1,2) symmetry are derived.

hep-th↗
arXiv1999

Does the Weyl ordering prescription lead to the correct energy levels for the quantum particle on the D-dimensional sphere ?

The energy eigenvalues of the quantum particle constrained in a surface of the sphere of D dimensions embedded in a $R^{D+1}$ space are obtained by using two different procedures: in the first, we derive the Hamiltonian operator by squaring the expression of the momentum, written in cartesian components, which satisfies the Dirac brackets between the canonical operators of this second class system. We use the Weyl ordering prescription to construct the Hermitian operators. When D=2 we verify that there is no constant parameter in the expression of the eigenvalues energy, a result that is in agreement with the fact that an extra term would change the level spacings in the hydrogen atom; in the second procedure it is adopted the non-abelian BFFT formalism to convert the second class constraints into first class ones. The non-abelian first class Hamiltonian operator is symmetrized by also using the Weyl ordering rule. We observe that their energy eigenvalues differ from a constant parameter when we compare with the second class system. Thus, a conversion of the D-dimensional sphere second class system for a first class one does not reproduce the same values.

hep-th↗
arXiv1999

Operatorial quantization of Born-Infeld Skyrmions

The SU(2) collective coordinates quantization of the Born-Infeld Skyrmions Lagrangean is performed. The obtainment of the classical Hamiltonian from this special Lagrangean is made by using an approximate way: it is derived from the expansion of this non-polynomial Lagrangean up to second-order variable in the collective coordinates, using for this some causality arguments. Because this system presents constraints, we use the Dirac Hamiltonian method and the Faddeev-Jackiw Lagrangean approach to quantize this model.

hep-th↗