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Black hole as a trampoline: why dust flies away ✛ ✎ ✦

Original: "Random walks around black holes and low-frequency X-ray variability"
· Arthur G. Suvorov
arXiv:2607.14626 · 2026-07-16 · arXiv non-exclusive · independent analysis · 1 min
General Relativity High Energy
Curved space around a black hole works like a trampoline: particles more often fly outward than fall in.

Even Einstein and Schwarzschild showed that the space around black holes is curved. But a new perspective revealed: this curvature doesn’t suck cosmic dust in but flings it away — like a trampoline.

In the rotating disk of dust and superheated gas (a model developed by Sunyaev), particles move chaotically. Closer to the hole, space seems to stretch, even accounting for dark energy, and time slows down: the particle almost hangs in place.

It's easier for a dust grain to fly away than to crash into the hole — geometry works like a trampoline.

This explains why the X-ray flickering of Cygnus X-1 looks different. Computer calculations of millions of trajectories showed: the radiation fluctuations smooth out at low frequencies — exactly as observed by telescopes. An additional contribution comes from gravitational stretching of light. Thus astrophysicists got a tool to test strong gravity directly through observations.

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Because of space stretching, it's easier for a dust grain to fly away from a black hole than to fall into it — as if the cosmos works like a trampoline.

P_H(r) = \frac{\int_r^{r_c} \frac{du}{u^2 \sqrt{f(u)}}}{\int_{r_H}^{r_c} \frac{du}{u^2 \sqrt{f(u)}}}
Probability that a dust grain starting at radius r will be captured by the event horizon before reaching the cosmological horizon.
\frac{\partial P}{\partial t} = \frac{1}{2} \nabla_\mu \left( \sigma^2 \nabla^\mu P \right)
Evolution of the probability density P for Brownian motion with diffusion coefficient σ on a Riemannian manifold.
Scientists
Stephen HawkingJacob BekensteinJohn Archibald WheelerFritz ZwickyKarl SchwarzschildJoseph Weber
Concepts
random walk black hole variability black hole dynamics Fokker–Planck equation quantum walk ornstein uhlenbeck process wald entropy stochastic fluctuations accretion disk wind variability innermost stable circular orbit random variable classical gravity biological stochastic dynamics wormhole resonance Wright–Fisher model broad emission lines spacetime foam schwarzschild radius variance