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Non-Extensive Thermodynamics Effects in the Cosmology of f(T) Gravity

Asmaa G. Shalaby, Vasilis K. Oikonomou, Gamal G. L. Nashed
2021 Symmetry  
quantifies the non-extensive thermodynamics effects quantified by the parameter δ, which when is set equal to unity, one recovers the field equations of f(T) gravity.  ...  Using f(T) gravitational theory, we construct modified cosmological models via the first law of thermodynamics by using the non-extensive thermodynamics framework, the effects of which are captured by  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/sym13010075 fatcat:oplzqhsql5clldqzphbzatmyvy

Cosmological reconstruction of f(T, 𝒯) gravity

Davood Momeni, Ratbay Myrzakulov
2014 International Journal of Geometric Methods in Modern Physics (IJGMMP)  
Motivated by the newly proposal for gravity as the effect of the torsion scalar T and trace of the energy momentum tensor T,we investigate the cosmological reconstruction of different models of the Universe  ...  Our aim here is to show that how this modified gravity model, f(T,T) is able to reproduce different epoches of the cosmological history.  ...  Saridakis for useful comments and the anonymous reviewer for enlightening comments related to this work.  ... 
doi:10.1142/s0219887814500777 fatcat:4maaeno7rrfnlfr5w2kgypxhlu

f(Q, T) gravity

Yixin Xu, Guangjie Li, Tiberiu Harko, Shi-Dong Liang
2019 European Physical Journal C: Particles and Fields  
We propose an extension of the symmetric teleparallel gravity, in which the gravitational action L is given by an arbitrary function f of the nonmetricity Q and of the trace of the matter energy-momentum  ...  We consider several cosmological models by imposing some simple functional forms of the function f(Q,T), corresponding to additive expressions of f(Q,T) of the form f(Q,T)=α Q+β T, f(Q,T)=α Q^n+1+β T,  ...  Data Availability Statement This manuscript has no associated data or the data will not be deposited [Authors' comment: There are no data for this study.]  ... 
doi:10.1140/epjc/s10052-019-7207-4 fatcat:3qtb5x53oba2llgaqv6x6dsqei

Growth factor inf(T,T)gravity

Gabriel Farrugia, Jackson Levi Said
2016 Physical Review D  
We investigate the growth factor for sub-horizon modes during late times in f(T,T) gravity, where T is the torsion scalar and T is the trace of the stress-energy tensor.  ...  Furthermore, the role of the anisotropic term π^S is investigated.  ...  The research work disclosed in this paper is partially funded by the ENDEAVOUR Scholarships Scheme.  ... 
doi:10.1103/physrevd.94.124004 fatcat:4dqpcxabifcanancx5lsmxcyq4

Constrainingf(T,T)gravity models using type Ia supernovae

Diego Sáez-Gómez, C. Sofia Carvalho, Francisco S. N. Lobo, Ismael Tereno
2016 Physical Review D  
We present an analysis of an f(T, T) extension of the Teleparallel Equivalent of General Relativity, where T denotes the torsion and T the trace of the energy-momentum tensor.  ...  In particular, we construct two specific models that recover the usual continuity equation, namely, f(T, T)=T+g(T) and f(T, T)=T× g(T).  ...  In fact, f (T ) gravity theories have been explored in a wide variety of aspects, namely alternative cosmological models [10] , observational constraints [11] , thermodynamics [12] , static solutions  ... 
doi:10.1103/physrevd.94.024034 fatcat:ypohoe2i2rgvrhdqpi2c5tsarm

Reconstruction, thermodynamics and stability of the ΛCDM model in $f(T,{ \mathcal T })$ gravity

Ednaldo L B Junior, Manuel E Rodrigues, Ines G Salako, Mahouton J S Houndjo
2016 Classical and quantum gravity  
We reconstruct the ΛCDM model for f(T,T) Theory, where T is the torsion scalar and T the trace of the energy-momentum tensor.  ...  We show that to maintain conservation of energy-momentum tensor should impose that F_g[y] must be linear on the trace T. This reconstruction decays in the f(T) Theory for F_g≡ Q, with Q a constant.  ...  Ines G. Salako thanks IMSP for hospitality during the elaboration of this work.  ... 
doi:10.1088/0264-9381/33/12/125006 fatcat:asyb6xkr3zepvjgdumxy7pp4d4

Cosmological Issues in F(T) Gravity Theory [article]

Kazuharu Bamba
2015 arXiv   pre-print
We explore various cosmological aspects of F(T) gravity including the evolution of the equation of state for the universe, finite-time future singularities, thermodynamics, and four-dimensional effective  ...  We review recent developments on cosmology in extended teleparallel gravity, called "F(T) gravity" with T the torsion scalar in teleparallelism.  ...  Furthermore, he is really grateful to all of the collaborators of our studies in terms of F (T ) gravity, especially, all the co-authors of the works in Refs.  ... 
arXiv:1504.04457v2 fatcat:7imvp4tmqjfdhk3vgze7c4335m

Energy-momentum squared symmetric Teleparallel gravity: f(Q,T_μνT^μν) gravity [article]

Prabir Rudra
2021 arXiv   pre-print
In this work we propose the f(Q,T_μνT^μν) gravity as a further extension of the f(Q) and f(Q,T) gravity theories.  ...  The action involves an arbitrary function of the non-metricity Q and T_μνT^μν in the gravity Lagrangian.  ...  Acknowledgments The author acknowledges the Inter University Centre for Astronomy and Astrophysics (IUCAA), Pune, India for granting visiting associateship.  ... 
arXiv:2107.10240v1 fatcat:tam7swl5ond43ju3ife4rbudoe

Non-minimal geometry-matter couplings in Weyl-Cartan space-times: Myrzakulov f(R,T,Q,T) gravity [article]

Tiberiu Harko, Nurgissa Myrzakulov, Ratbay Myrzakulov, Shabab Shahidi
2021 arXiv   pre-print
A thermodynamic interpretation of the nonconservation of the energy-momentum tensor is also developed in the framework of the thermodynamics of the irreversible processes in open systems.  ...  We investigate the cosmological implications of the theory for two different choices of the gravitational action, corresponding to an additive and a multiplicative algebraic structure of the function f  ...  The action of the theory is given by S = [f (R, T ) + L m ] √ −gd 4 x. The astrophysical and cosmological applications of f (R, T ) theory were studied extensively in .  ... 
arXiv:2110.00358v1 fatcat:fxvs7cg4ibbtbjtjhc5sz5l56i

Friedmann cosmology with particle creation in modified f(R,T) gravity [article]

C.P.Singh, Vijay Singh
2014 arXiv   pre-print
The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified f(R,T) (R is the Ricci scalar and T is the trace of energy-momentum  ...  A simplest particular model f(R,T)=R+2f(T) and "gamma-law" equation of state p=(γ-1)ρ are assumed to explore the role of particle creation in the early and late time evolution of the universe.  ...  Sharif and Zubair 63 have discussed a non-equilibrium thermodynamics in f (R, T ) gravity by taking two forms of the energy-momentum tensor of dark components which endorses second law of thermodynamics  ... 
arXiv:1408.0633v2 fatcat:5jqtvy2esbfs3im4vj2ccs4d3u

Energy conditions in f(Q,T) gravity

Simran Arora, Pradyumn Kumar Sahoo
2020 Physica Scripta  
The recently proposed f(Q, T) gravity (Xu et al. Eur. Phys. J. C 79 (2019) 708) is an extension of the symmetric teleparallel gravity.  ...  In this paper, we examined the essence of some well prompted forms of f(Q,T) gravity models i.e. f(Q,T)= mQ+bT and f(Q,T)= m Q^n+1+b T where m, b, and n are model parameters.  ...  The coupling between Q and T results in the non-conservation of the energy-momentum tensor, which entails some significant thermodynamic change of the Universe as in f (R, T) gravity [6] .  ... 
doi:10.1088/1402-4896/abaddc fatcat:vilpgnilm5bsdabpcul6g4ni7e

Bulk viscosity in F(T, TG) gravity

M. Sharif, Kanwal Nazir
2017 Canadian journal of physics (Print)  
Concluding Remarks In cosmology, viscous fluid models have extensively been considered to explore expanding nature of the universe.  ...  Many dark energy models have been discussed in F (G) gravity as well [17, 18] . In this paper, we evaluate the EoS parameter by introducing bulk viscosity in the background of F (T, T G ) gravity.  ... 
doi:10.1139/cjp-2016-0785 fatcat:h7ag2ivynnfk5lk3d2kjrqnctu

Further matters in space-time geometry:f(R,T,RμνTμν)gravity

Zahra Haghani, Tiberiu Harko, Francisco S. N. Lobo, Hamid Reza Sepangi, Shahab Shahidi
2013 Physical Review D  
We consider a gravitational model in which matter is non-minimally coupled to geometry, with the effective Lagrangian of the gravitational field being given by an arbitrary function of the Ricci scalar  ...  The cosmological implications of the model are investigated for both the conservative and non-conservative cases, and several classes of analytical solutions are obtained.  ...  The astrophysical and cosmological implications of the f (R, T ) gravity theory have been extensively investigated recently [32] .  ... 
doi:10.1103/physrevd.88.044023 fatcat:6jlmaljyfjbklesay5lwxhofsu

Holographic polytropic f(T)-gravity models [article]

Surajit Chattopadhyay, Abdul Jawad, Shamaila Rani
2015 arXiv   pre-print
The present paper reports a study on the cosmological consequences arising from reconstructing f(T) gravity through new holographic-polytropic dark energy.  ...  We obtain the deceleration parameter, effective equation of state as well as torsion equation of state parameters from total density and pressure in both cases.  ...  However, the maximum entropy in a box possessing volume L 3 (growing with the area of the box) behaves non-extensively in the framework of BH thermodynamics so called Bekenstein entropy bound.  ... 
arXiv:1510.01611v1 fatcat:plerwrmqinbbfcwnxn25klvvii

Violation of the First Law of Thermodynamics inf(R,T) Gravity

Mubasher Jamil, D. Momeni, Ratbay Myrzakulov
2012 Chinese Physics Letters  
We have proved, in general, that the first law of black bole thermodynamics is violated for f(R,T) gravity.  ...  But there might exist some special cases in which the first law for f(R,T) gravity is recovered.  ...  This model is an extension of a former model f (R). In this extension, there is a non-minimally coupling between the Ricci scalar R and the trace of the energy-momentum tensor.  ... 
doi:10.1088/0256-307x/29/10/109801 fatcat:nf6wekdffragbh7mmm3ec3eqve
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