Black hole with confining electric potential in scalar-tensor description of regularized 4-dimensional Einstein-Gauss-Bonnet gravity

Овгун, Али

doi:10.1016/j.physletb.2021.136517

Cited by 45 publications

(13 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…). (20) Note that one can neglect the plasma medium effect by ( ω e ω ∞ → 0); then, this deflection angle in Equation ( 20) reduces into the angle in Equation (13).…”

Section: Effect Of Plasma On Gravitational Lensingmentioning

confidence: 99%

Weak Deflection Angle and Shadow by Tidal Charged Black Hole

2021

Self Cite

View full text Add to dashboard Cite

In this article, we calculate the deflection angle of a tidal charged black hole (TCBH) in weak field limits. First, we obtain the Gaussian optical curvature and then apply the Gauss–Bonnet theorem on it. With the help of Gibbons–Werner method, we are able to calculate the light’s deflection angle by TCBH in weak field limits. After calculating the deflection angle of light, we check the graphical behavior of TCBH. Moreover, we further find the light’s deflection angle in the presence of the plasma medium and also check the graphical behavior in the presence of the plasma medium. Moreover, we investigate the shadow of TCBH. For calculating the shadow, we first find the null geodesics around the TCBH and then find its shadow radius. We also obtain TCBH’s shadow in the plasma medium. Hence, we discuss the shadow of the TCBH, using the M87* parameters announced by the event horizon telescope.

show abstract

“…). (20) Note that one can neglect the plasma medium effect by ( ω e ω ∞ → 0); then, this deflection angle in Equation ( 20) reduces into the angle in Equation (13).…”

Section: Effect Of Plasma On Gravitational Lensingmentioning

confidence: 99%

Weak Deflection Angle and Shadow by Tidal Charged Black Hole

2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…Pantig et al [72,73] have studied the possible effects of dark matter on a Schwarzschild black hole with the correction of extended uncertainty principle on black hole shadow and also effect of dark matter on the weak deflection angle by black holes at the galactic center. Övgün has showed [74] that a confining charge gives a significant contribution to the shadow of the black hole with confining electric potential in scalar-tensor description of regularized 4dimensional Einstein-Gauss-Bonnet gravity. Okyay and Övgün have studied the nonlinear electrodynamics effects on the black hole shadow [75].…”

Section: Introductionmentioning

confidence: 99%

Testing dynamical torsion effects on the charged black hole's shadow, deflection angle and greybody with M87* and Sgr A* from EHT

Pantig¹,

Овгун²

2022

Preprint

View full text Add to dashboard Cite

Poincare Gauge's theory of gravity is the most noteworthy alternative extension of general relativity that has a correspondence between spin and spacetime geometry. In this paper, we used Reissner-Nordstrom-de Sitter and anti-de Sitter solutions, where torsion τ is added as an independent field, to analyze the weak deflection angles α of massive and null particles in finite distance regime. We then applied α to determine the Einstein ring formation in M87* and Sgr. A* and determine that relative to Earth's location from these black holes, massive torsion effects can provide considerable deviation, while the cosmological constant's effect remains negligible. Furthermore, we also explored how the torsion parameter affects the shadow radius perceived by both static and co-moving (with cosmic expansion) observers in a Universe dominated by dark energy, matter, and radiation. Our findings indicate that torsion and cosmological constant parameters affect the shadow radius differently between observers in static and co-moving states. We have also shown how the torsion parameter affects the luminosity of the photonsphere by studying the shadow with infalling accretion. The calculation of the quasinormal modes, greybody bounds, and high-energy absorption cross-section was also affected by the torsion parameter considerably.

show abstract

“…In the frame of modified gravitational theories there are many studies tackling the problem of anisotropic compact stars for example in the frame of f (R, G), where R is the Ricci scalar and G is the Gauss-Bonnet term [34], in the frame of mimetic theory [35], in the frame of f (R) [36][37][38][39], in the frame of teleparallel gravity [40,41], and in the frame of scalar Gauss-Bonnet theory [42].…”

Section: Introductionmentioning

confidence: 99%

Anisotropic Compact Stars in D → 4 Limit of Gauss–Bonnet Gravity

2022

View full text Add to dashboard Cite

In the frame of Gauss–Bonnet gravity and in the limit of D→4, based on the fact that spherically symmetric solution derived using any of regularization schemes will be the same form as the original theory, we derive a new interior spherically symmetric solution assuming specific forms of the metric potentials that have two constants. Using the junction condition we determine these two constants. By using the data of the star EXO 1785-248, whose mass is M=1.3±0.2M⊙ and radius l=8.849±0.4 km, we calculate the numerical values of these constants, in terms of the dimensionful coupling parameter of the Gauss–Bonnet term, and eventually, we get real values for these constants. In this regard, we show that the components of the energy–momentum tensor have a finite value at the center of the star as well as a smaller value to the surface of the star. Moreover, we show that the equations of the state behave in a non-linear way due to the impact of the Gauss–Bonnet term. Using the Tolman–Oppenheimer–Volkoff equation, the adiabatic index, and stability in the static state we show that the model under consideration is always stable. Finally, the solution of this study is matched with observational data of other pulsars showing satisfactory results.

show abstract

Black hole with confining electric potential in scalar-tensor description of regularized 4-dimensional Einstein-Gauss-Bonnet gravity

Cited by 45 publications

References 54 publications

Weak Deflection Angle and Shadow by Tidal Charged Black Hole

Weak Deflection Angle and Shadow by Tidal Charged Black Hole

Testing dynamical torsion effects on the charged black hole's shadow, deflection angle and greybody with M87* and Sgr A* from EHT

Anisotropic Compact Stars in D → 4 Limit of Gauss–Bonnet Gravity

Contact Info

Product

Resources

About