A perturbative approach to neutron stars in $$f(T, \mathcal {T})$$ f ( T , T ) -gravity

Abstract

We derive a Tolman-Oppenheimer-Volkoff equation in neutron star systems within the modified f (T, T ) -gravity class of models using a perturbative approach. In our approach f (T, T )-gravity is considered to be a static spherically symmetric space-time. In this instance the metric is built from a more fundamental vierbein which can be used to relate inertial and global coordinates. A linear func-is taken as the Lagrangian density for the gravitational action. Finally we impose the polytropic equation of state of neutron star upon the derived equations in order to derive the mass profile and mass-central density relations of the neutron star in f (T, T )-gravity.

Photon sphere and perihelion shift in weak f(T) gravity

“…In addition, some regular black hole solutions (perturbatively and exact) have been found correctly in [14,15]. When one considers matter, there are some works which have studied the possibility of constructing stars or wormhole solutions in different teleparallel theories of gravity [16][17][18][19][20][21][22][23][24]. Overall the issue of finding exact spherically symmetric solutions in f (T )-gravity is still an open problem.…”

Study on Anisotropic Strange Stars in f ( T , T ) Gravity

“…f (T, T ) = ωT n T − 2Λ, to present a simple mathematical model following the prescription by Harko et al [62] to comply with the observational data. However, after successful execution of this specification, there are ample scopes to opt for other specified functional forms of f (T, T ) gravity in the future projects following other ansatz, e.g., f (T, T ) = αT + γT 2 which has been also proposed by Harko et al [62] or linear function in the forms (i) f = αT(r) + βT (r) + ϕ as proposed by Pace and Said [74] and (ii) f = T(r) + T (r) + h(T, T ) + O( 2 ) as proposed by Pace and Said [75]. In the above ansatz, which has been employed in the present work, the value of n is assumed to be unity, i.e., n = 1, however n = 1 case also can be considered for further study.…”

“…(2) In the present work, we have considered tetrad formalism to correspond to the metric (25), however, it is known that in spherically-symmetric solutions the diagonal tetrad is not the consistent choice. In this connection it is of note that in literature this type of approach is not at all unavailable even in the f (T, T ) gravity theory [62,[73][74][75]. The tetrad formalism has been used by Harko et al [62] in cosmology whereas Pace and Said [74,75] as well as Ghosh et al [73] have employed the technique in astrophysics.…”

“…We note from literature survey that almost all the works under the background of f (T, T ) gravity have been performed in different cosmological context [62][63][64][65][66][67][68][69][70][71][72][73]. However, there are a few astrophysical applications of f (T, T ) gravity as can be found in the works of Pace and Said [74,75]. Pace and Said have studied quark star incorporating the MIT bag model [74] and neutron star models using a perturbative approach [75] in f (T, T ) gravity theory whereas gravastars have been investigated by Ghosh et al [73] in the same alternative theory of gravity.…”

“…However, there are a few astrophysical applications of f (T, T ) gravity as can be found in the works of Pace and Said [74,75]. Pace and Said have studied quark star incorporating the MIT bag model [74] and neutron star models using a perturbative approach [75] in f (T, T ) gravity theory whereas gravastars have been investigated by Ghosh et al [73] in the same alternative theory of gravity.…”