Redshift/blueshift inside the Schwarzschild black hole

Abstract

We consider an observer who moves under the horizon of the Schwarzschild black hole and absorbs a photon. There are two different situations when (i) a photon comes from infinity, (ii) it is emitted by another observer under the horizon (say, by a surface of a collapsing star). We analyze the frequency change for absorption near the event horizon, in an intermediate region and near the singularity and compare the results for both scenarios. Near the singularity, in both scenarios infinite redshift (in the pure radial case) or infinite blueshift are possible, depending on angular momenta of a photon and an observer. The main difference between both scenarios manifests itself, if photons from the star surface are emitted near the horizon and received in the intermediate region or near the singularity by the observer with a nonzero angular momentum.

21 pages. Substantial revision. To appear in Gen. Rel. Grav

References in corpus (7)

• Interior of a Schwarzschild black hole revisited
• Are black holes totally black?
• Acceleration of particles near the inner black hole horizon
• Stereoscopic visualization in curved spacetime: seeing deep inside a black hole
• Zero-momentum trajectories inside a black hole and high energy particle collisions
• Redshift of a photon emitted along the black hole horizon
• Why ghosts don't touch: a tale of two adventurers falling one after another into a black hole

Cited by in corpus (3)

• Flow and peculiar velocities for generic motion in spherically symmetric black holes
• On particle dynamics near the singularity inside the Schwarzschild black hole and T-spheres
• Dynamics of redshift/blueshift during free fall under the Schwarzschild horizon