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A. Plastino

Publications and source records attributed to A. Plastino.

At least 19 recordsLinked to original sources

Gupta-Feynman based Quantum Field Theory of Einstein's Gravity

This paper is an {\sf application} to Einstein's gravity (EG) of the mathematics developed in A. Plastino, M. C. Rocca: J. Phys. Commun. {\bf 2}, 115029 (2018). We will quantize EG by appeal to the most general quantization approach, the Schwinger-Feynman variational principle, which is more appropriate and rigorous that the functional integral method, when we are in the presence of derivative couplings \nd We base our efforts on works by Suraj N. Gupta and Richard P. Feynman so as to undertake the construction of a Quantum Field Theory (QFT) of Einstein Gravity (EG). We explicitly use the Einstein Lagrangian elaborated by Gupta \cite{g1} but choose a new constraint for the theory that differs from Gupta's one. In this way, we avoid the problem of lack of unitarity for the $S$ matrix that afflicts the procedures of Gupta and Feynman. Simultaneously, we significantly simplify the handling of constraints. This eliminates the need to appeal to ghosts for guarantying the unitarity of the theory. Our ensuing approach is obviously non-renormalizable. However, this inconvenience can be overcome by appealing tho the mathematical theory developed by Bollini et al. \cite{tp3,tp18,tp19,tp20,pr} Such developments were founded in the works of Alexander Grothendieck \cite{gro} and in the theory of Ultradistributions of Jose Sebastiao e Silva \cite{tp6} (also known as Ultrahyperfunctions). Based on these works, we have constructed a mathematical edifice, in a lapse of about 25 years, that is able to quantize non-renormalizable Field Theories (FT). Here we specialize this mathematical theory to treat the quantum field theory of Einsteins's gravity (EG). Because we are using a Gupta-Feynman inspired EG Lagrangian, we are able to evade the intricacies of Yang-Mills theories.

physics.gen-ph

Generalized probabilities in statistical theories

In this review article we present different formal frameworks for the description of generalized probabilities in statistical theories. We discuss the particular cases of probabilities appearing in classical and quantum mechanics, possible generalizations of the approaches of A. N. Kolmogorov and R. T. Cox to non-commutative models, and the approach to generalized probabilities based on convex sets.

stat.OT

Pure-state density matrix that competently describes classical chaos

We work with reference to a well-known semiclassical model, in which quantum degrees of freedom interact with classical ones. We show that, in the classical limit, it is possible to represent classical results (e.g., classical chaos) by means a pure-state density matrix.

quant-ph

Relativistic treatment of Verlinde's emergent force in Tsallis' statistics

Following Chakrabarti,Chandrasekhar, and Naina [Physica A {\bf 389} (2010) 1571], we attempt a classical relativistic treatment of Verlinde's emergent entropic force conjecture by appealing to a relativistic Hamiltonian in the context of Tsalli's statistics. The ensuing partition function becomes the classical one for small velocities. We show that Tsallis' relativistic (classical) free particle distribution at temperature $T$ can generate Newton's gravitational force's $r^{-2}$ {\it distance's dependence}. If we want to repeat the concomitant argument by appealing to Renyi's distribution, the attempt fails and one needs to modify the conjecture.

cond-mat.stat-mech

A rigorous calculation of the Feynman and Wheeler Scalar Fields propagators in the ADS / CFT correspondence using distribution theory

By appeal to Distribution Theory we discuss in rigorous fashion, without appealing to {\bf any conjecture} (as usually done by other authors), the boundary-bulk propagators for the scalar field, both in the non-massive and massive cases. These calculations, new in the literature as far as we know, are carried out in two instances: (i) when the boundary is a Euclidean space and (ii) when it is of Minkowskian nature. In this last case we compute also three propagators: Feynman's, Anti-Feynman's, and Wheeler's (half advanced plus half retarded). For an operator corresponding to scalar field we obtain the two points correlations functions in the three instances above mentioned

hep-th

Deformed Tsallis-statistics analysis of a complex nonlinear matter-field system

We study, using information quantifiers, the dynamics generated by a special Hamiltonian that gives a detailed account of the interaction between a classical and a quantum system. The associated, very rich dynamics displays periodicity, quasi-periodicity, not-boundedness, and chaotic regimes. Chaoticity, together with complex behavior, emerge in the proximity of an unstable entirely quantum instance. Our goal is to compare the statistical description provided by Tsallis quantifiers vis a vis that obtained with Shannon's entropy and Jensen's complexity.

cond-mat.stat-mech

Spatial cut-offs, Fermion Statistics, and Verlinde's Conjecture

Verlinde conjectured eight years ago that gravitation might be an emergent entropic force. This rather surprising assertion was proved in [Physica A {\bf 505} (2018) 190] within a purely classical statistical context, and in [DOI: 10.13140/RG.2.2.34454.24640] for the case of bosons' statistics. In the present work, we appeal to a quantum scenario involving fermions' statistics. We consider also the classical limit of quantum (statistical) mechanics (QM). We encounter a lower bound to the distance $r$ between the two interacting masses, i.e., an $r$ cut-off. This is a new effect that exhibits some resemblance with the idea of space discretization proposed by recent gravitation theories

physics.gen-ph

Quantum Field Theory, Feynman-, Wheeler Propagators, Dimensional Regularization in Configuration Space and Convolution of Lorentz Invariant Tempered Distributions

The Dimensional Regularization of Bollini and Giambiags (Phys. Lett. {\bf B 40}, 566 (1972), Il Nuovo Cim. {\bf B 12}, 20 (1972). Phys. Rev. {\bf D 53}, 5761 (1996)) can not be defined for all Schwartz Tempered Distributions Explicitly Lorentz Invariant (STDELI) ${\cal S}^{'}_L$. In this paper we overcome here such limitation and show that it can be generalized to all aforementioned STDELI and obtain a product in a ring with zero divisors. For this purpose, we resort to a formula obtained in [Int. J. of Theor. Phys. {\bf 43}, 1019 (2004)] and demonstrate the existence of the convolution (in Minkowskian space) of such distributions. This is done by following a procedure similar to that used so as to define a general convolution between the Ultradistributions of J. Sebastiao e Silva [Math. Ann. {\bf 136}, 38 (1958)], also known as Ultrahyperfunctions, obtained by Bollini et al. [Int. J. of Theor. Phys. {\bf 38}, 2315 (1999), {\bf 43}, 1019 (2004), {\bf 43}, 59 (2004),{\bf 46}, 3030 (2007)]. Using the Inverse Fourier Transform we get the ring with zero divisors ${\cal S}^{'}_{LA}$, defined as ${\cal S}^{'}_{LA}={\cal F}^{-1}\{{\cal S}^{'}_L\}$, where ${\cal F}^{-1}$ denotes the Inverse Fourier Transform. In this manner we effect a dimensional regularization in momentum space (the ring ${\cal S}^{'}_{L}$) via convolution, and a product of distributions in the corresponding configuration space (the ring ${\cal S}^{'}_{LA})$. This generalizes the results obtained by Bollini and Giambiagi for Euclidean space in [Phys. Rev. {\bf D 53}, 5761 (1996)]. We provide several examples of the application of our new results in Quantum Field Theory. In particular, the convolution of $n$ massless Feynman propagators and the convolution of n massless Wheeler propagators in Minkowskian space.

physics.gen-ph

Quantum statistical treatment of Verlinde's conjecture in a Tsallis framework

Verlinde has recently conjectured, via a Beckenstein-like thought experiment, that gravitation, instead of being an elementary force, is an emergent entropic one. This rather surprising conjecture was actually proved in [Physica A {\bf 505} (2018) 190], in a strictly classical statistical mechanics' environment. In this Communication, we work in a quantum statistical context to consider the conjecture in the case of bosons/fermions, in a Tsallis' framework. We prove that Tsallis' entropy is the operating potential energy in this quantum treatment, something that does not happen in the case of Boltzmann-Gibbs' entropy. \color{red} In the classical limit, we show that the emergent force has a Newtonian dependence with the distance.

physics.gen-ph

Reciprocity relations and generalized entropic quantifiers that lack trace-form

In this effort we show that the Legendre reciprocity relations,thermodynamic's essential formal feature, are respected by any entropic functional, even if it is NOT of trace-form nature, as Shannon's is. Further, with reference to the MaXent variational process, we encounter important cases, relevant to physical applications currently discussed in the research literature, in which the associated reciprocity relations exhibit anomalies. We show that these anomalies can be cured by carefully discriminating between apparently equivalent entropic forms.

cond-mat.stat-mech

Features of constrained entropic functional variational problems

We describe in great generality features concerning constrained entropic, functional variational problems that allow for a broad range of applications. Our discussion encompasses not only entropies but, potentially, any functional of the probability distribution, like Fisher-information or relative entropies, etc. In particular, in dealing with generalized statistics in straightforward fashion one may sometimes find that the first thermal law $\frac{dS}{dβ}=β\frac{d }{dβ}$ seems to be not respected. We show here that, on the contrary, it is indeed obeyed by any system subject to a Legendre extremization process, i.e., in all constrained entropic variational problems.

cond-mat.stat-mech

Quantum treatment of Verlinde's entropic force conjecture

Verlinde conjectured that gravitation is an emergent entropic force. This surprising conjecture was proved in [Physica A {\bf 505} (2018) 190] within a purely classical context. Here, we appeal to a quantum environment to deal with the conjecture in the case of bosons and consider also the classical limit of quantum mechanics (QM).

physics.gen-ph

Verlinde's emergent gravity in an $\boldsymbol{n-}$dimensional, non-additive Tsallis' scenario

This paper brings together four distinct but very important physical notions: 1) Entropic force, 2) Entropy-along-a-curve, 3) Tsallis' q-statistics, and 4) Emergent gravitation. We investigate the non additive, classical (Tsallis') q-statistical mechanics of a phase-space curve in $n$ dimensions (3 dimensions, in particular). We focus attention on an entropic force mechanism that yields a simple realization of it, being able to mimic interesting effects such as confinement, hard core, and asymptotic freedom, typical of high energy physics

physics.gen-ph

Newton's gravitation-force's classical average proof of a Verlinde's conjecture

A surprising, gravity related Verlinde-conjecture, that generated immense interest, asserts that gravity is an emergent entropic force. We provided a classical proof of the assertion in [doi.org/j.physa.2018.03.019]. Here, we classically prove a related, second Verlinde-conjecture. This states that, at very large distances ($r_0$), gravity departs from its classical nature and begins to decay linearly with $r_0$.

physics.gen-ph

Tsallis' Quantum q-Fields

We generalize several well known quantum equations to a Tsallis' q-scenario, and provide a quantum version of some classical fields associated to them in recent literature. We refer to the q-Schrödinger, q-Klein-Gordon, q-Dirac, and q-Proca equations advanced in, respectively, [Phys. Rev. Lett. {\bf 106}, 140601 (2011), EPL {\bf 118}, 61004 (2017) and references therein]. Also, we introduce here equations corresponding to q-Yang-Mills fields, both in the Abelian and not-Abelian instances. We show how to define the q-Quantum Field Theories corresponding to the above equations, introduce the pertinent actions, and obtain motion equations via the minimum action principle. These q-fields are meaningful at very high energies (TeVs) for $q=1.15$, high ones (GeVs) for $q=1.001$, and low energies (MeVs)for $q=1.000001$ [Nucl. Phys. A {\bf 955} (2016) 16 and references therein]. (See the Alice experiment of LHC). Surprisingly enough, these q-fields are simultaneously q-exponential functions of the usual linear fields' logarithms.

physics.gen-ph

On the entropic derivation of the $r^{-2}$ Newtonian gravity force

Following Verlinde's conjecture, we show that Tsallis' classical free particle distribution at temperature $T$ can generate Newton's gravitational force's $r^{-2}$ {\it distance's dependence}. If we want to repeat the concomitant argument by appealing to either Boltzmann-Gibbs' or Renyi's distributions, the attempt fails and one needs to modify the conjecture. Keywords: Tsallis', Boltzmann-Gibbs', and Renyi's distributions, classical partition function, entropic force.

gr-qc

Dimensionally regularized Boltzmann-Gibbs Statistical Mechanics and two-body Newton's gravitation

It is believed that the canonical gravitational partition function $Z$ associated to the classical Boltzmann-Gibbs (BG) distribution $\frac {e^{-βH}} {\cal Z}$ cannot be constructed because the integral needed for building up $Z$ includes an exponential and thus diverges at the origin. We show here that, by recourse to 1) the analytical extension treatment obtained for the first time ever, by Gradshteyn and Rizhik, via an appropriate formula for such case and 2) the dimensional regularization approach of Bollini and Giambiagi's (DR), one can indeed obtain finite gravitational results employing the BG distribution. The BG treatment is considerably more involved than its Tsallis counterpart. The latter needs only dimensional regularization, the former requires, in addition, analytical extension.

physics.gen-ph

Dimensionally regularized Tsallis' Statistical Mechanics and two-body Newton's gravitation

Typical Tsallis' statistical mechanics' quantifiers like the partition function and the mean energy exhibit poles. We are speaking of the partition function ${\cal Z}$ and the mean energy $<{\cal U}>$. The poles appear for distinctive values of Tsallis' characteristic real parameter $q$, at a numerable set of rational numbers of the $q-$line. These poles are dealt with dimensional regularization resources. The physical effects of these poles on the specific heats are studied here for the two-body classical gravitation potential.

cond-mat.stat-mech