Soft-haired Kerr black holes show rotated, dilated, drifting images and an image memory effect when soft hair changes via waves, with the effect scaling with the large black hole's mass and spin.
Black hole shadow in an expanding universe with a cosmological constant
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
We analytically investigate the influence of a cosmic expansion on the shadow of the Schwarzschild black hole. We suppose that the expansion is driven by a cosmological constant only and use the Kottler (or Schwarzschild-deSitter) spacetime as a model for a Schwarzschild black hole embedded in a deSitter universe. We calculate the angular radius of the shadow for an observer who is comoving with the cosmic expansion. It is found that the angular radius of the shadow shrinks to a non-zero finite value if the comoving observer approaches infinity.
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gr-qc 4roles
background 1polarities
background 1representative citing papers
Quintessence black holes produce observer-dependent shadow angular sizes, with infalling observers seeing smaller shadows than static ones, yielding stronger equation-of-state constraints from M87* observations.
EHT observations of Sgr A* constrain deviations from GR black hole solutions including regular BHs, string-inspired spacetimes, and BH mimickers, with some limits exceeding cosmological bounds.
EHT shadow observations constrain the Lorentz-violating parameter ℓ in Kalb-Ramond gravity for charged rotating black holes to roughly |ℓ| ≲ 0.1-0.2, with an upper bound ℓ ≲ 0.19 from Sgr A*.
citing papers explorer
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Shaving off soft hairs and the black hole image memory effect
Soft-haired Kerr black holes show rotated, dilated, drifting images and an image memory effect when soft hair changes via waves, with the effect scaling with the large black hole's mass and spin.
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Shadows of quintessence black holes: spherical accretion, photon trajectories, and geodesic observers
Quintessence black holes produce observer-dependent shadow angular sizes, with infalling observers seeing smaller shadows than static ones, yielding stronger equation-of-state constraints from M87* observations.
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Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A$^*$
EHT observations of Sgr A* constrain deviations from GR black hole solutions including regular BHs, string-inspired spacetimes, and BH mimickers, with some limits exceeding cosmological bounds.
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Probing Kalb-Ramond gravity with charged rotating black holes: constraints from EHT observations
EHT shadow observations constrain the Lorentz-violating parameter ℓ in Kalb-Ramond gravity for charged rotating black holes to roughly |ℓ| ≲ 0.1-0.2, with an upper bound ℓ ≲ 0.19 from Sgr A*.