Faizuddin Ahmed

Physicists studied a black hole in two-dimensional space to test a modified theory of gravity. It turned out that even in such a universe, a black hole exists, but its property responsible for accelerated expansion changes. Then the scientists calculated the motion of particles and light around it.

A new model combines loop quantum gravity and dark energy, giving birth to a black hole with a triple horizon. This layered structure affects the shadow, vibrations, and light deflection, promising to become a key to testing quantum gravity and the nature of the universe's accelerating expansion.

Physicists have found that the shape of a water vortex's sound shadow can precisely measure its rotation speed. The main surprise: the mathematics of an ordinary sink plug and a giant black hole are the same.

Physicists examined two classic time machine designs within extended gravity featuring an extra field. The time loops didn’t collapse, and the chronology protection hypothesis failed. Even souped-up gravity doesn’t forbid time travel, which matters for testing modified theories.