Tong Liu

Light fades like a campfire when you stop adding wood. Gamma-ray bursts, the brightest explosions in the Universe, have their own rhythm of fading. Astronomers took 85 such bursts caught by the Swift satellite and looked at how fast their brightness drops. Inside a burst hides a black hole that greedily sucks in matter.

Imagine a spotlight: if you look at it from the side, it glows dim red, but if you stare straight into it, it blinds you with white-blue light. That, according to new data, is exactly what the mysterious 'little red dots' in the early universe look like. They are giant black holes, objects with gravity so strong that even light cannot escape, turned edge-on to us.

At the heart of nearly every large galaxy shines an active nucleus — a supermassive black hole surrounded by a flat, rotating disk of incandescent gas. The disk itself flickers, but astrophysicists suspect that within it lurks a whole swarm of small, stellar-mass black holes.

The quantum world does not forgive forgetfulness. Throw a stone into a pond — the ripples spread and vanish, the information about the impact dissipates without a trace. In quantum mechanics, everything is different: the evolution of a system is reversible, and the past is never completely erased.

Every day, the brain sounds a little different. Yesterday, the thought of moving your left hand produced one pattern of electrical waves; today, it's slightly different. For a brain-computer interface (a device that turns mental commands into actions), this is a big problem: yesterday's settings don't work today.