Eddington-inspired Born Infeld gravity theory as an anisotropic equation of state on stars

Anisotropic equation of state of charged and neutral vector boson gases in a constant magnetic field: Astrophysical implications

Astronomische Nachrichten ◽

10.1002/asna.201713448 ◽

2017 ◽

Vol 338 (9-10) ◽

pp. 1127-1130 ◽

Cited By ~ 3

Author(s):

G. Quintero Angulo ◽

A. Pérez Martínez ◽

H. Pérez Rojas

Keyword(s):

Magnetic Field ◽

Equation Of State ◽

Constant Magnetic Field ◽

Vector Boson ◽

Neutral Vector ◽

Anisotropic Equation

Download Full-text

Accelerating Cosmologies with an Anisotropic Equation of State

The Astrophysical Journal ◽

10.1086/587451 ◽

2008 ◽

Vol 679 (1) ◽

pp. 1-5 ◽

Cited By ~ 134

Author(s):

Tomi Koivisto ◽

David F. Mota

Keyword(s):

Equation Of State ◽

Anisotropic Equation

Download Full-text

An anisotropic equation of state for high pressure, high temperature applications

10.31223/x5561d ◽

2021 ◽

Author(s):

Robert Myhill

Keyword(s):

Equation Of State ◽

Equations Of State ◽

Deformation Gradient ◽

Seismic Velocities ◽

San Carlos Olivine ◽

High Pressure High Temperature ◽

Wide Range ◽

Anisotropic Equation ◽

Scalar Properties ◽

San Carlos

This paper presents a strategy for consistently extending isotropic equations of state to model anisotropic materials over a wide range of pressures and temperatures under nearly hydrostatic conditions. The method can be applied to materials of arbitrary symmetry. The paper provides expressions for the deformation gradient tensor, the lattice parameters, the isothermal elastic compliance tensor and thermal expansivity tensor. Scalar properties including the Gibbs energy, volume and heat capacities are inherited from the isotropic equation of state. Other physical properties including the isothermal and isentropic stiffness tensors, the Grueneisen tensor and anisotropic seismic velocities can be derived from these properties.The equation of state is demonstrated using periclase (cubic) and San Carlos olivine (orthorhombic) as examples.

Download Full-text

Gravitational lensing by exotic objects

Modern Physics Letters A ◽

10.1142/s0217732317300312 ◽

2017 ◽

Vol 32 (34) ◽

pp. 1730031 ◽

Cited By ~ 11

Author(s):

Hideki Asada

Keyword(s):

Time Delay ◽

Equation Of State ◽

Gravitational Lensing ◽

Modified Gravity ◽

Standard Form ◽

Phenomenological Approach ◽

Gravity Theory ◽

Gravitational Lens ◽

Lens Model ◽

Modified Gravity Theory

This paper reviews a phenomenological approach to the gravitational lensing by exotic objects such as the Ellis wormhole lens, where the exotic lens objects may follow a non-standard form of the equation of state or may obey a modified gravity theory. A gravitational lens model is proposed in the inverse powers of the distance, such that the Schwarzschild lens and exotic lenses can be described in a unified manner as a one parameter family. As observational implications, the magnification, shear, photo-centroid motion and time delay in this lens model are discussed.

Download Full-text