Ep 23. Dissolving an Event Horizon

Dissolving an Event Horizon is the 23rd episode of PBS Space Time season 2020 and takes an in-depth exploration of the elusive and mysterious concept of black holes. The episode delves into the science behind the event horizon, which is the boundary surrounding a black hole where the gravitational pull is so strong that nothing, not even light, can escape.

The episode starts by explaining the origin of black holes and their basic characteristics, such as mass and spin. It then moves on to discuss the event horizon and the impact that it has on anything that gets too close to the black hole. The episode explains how the shape of the event horizon is determined and how its size depends on the black hole's mass and spin.

One of the fascinating aspects of black holes is that they seem to have a thermal radiation known as Hawking radiation, which is caused by quantum effects around the event horizon. This radiation has a perceivably high-temperature value that varies inversely with the black hole’s mass as per Math demonstration, which means that small black holes evaporate much faster than larger ones.

The implications of Hawking radiation lead to the new concept of a black hole's information paradox, which is a long-standing puzzle where a black hole appears to contradict the laws of quantum mechanics. Scientists are still working on resolving the paradox, and the episode discusses some of the exciting developments in this field.

The concept of a black hole's event horizon is not as well-defined as we may think, and the episode explores its "fuzziness" and how it might dissolve, thus dissolving the paradox. The episode explains that quantum mechanics dictates that particles can somehow exist on both sides of the event horizon, which means that the event horizon itself might not be as rigid as we have previously thought.

The episode then tackles the idea put forward by physicists Ahmed Almheiri, Donald Marolf, Joseph Polchinski, and James Sully of a resolution of the paradox, which involves dissolving the event horizon entirely, a concept known as the firewall.

Overall, the episode is an exciting journey through physics and cosmology, where we travel from the basics of event horizons and thermodynamics to deep questions about the nature of the universe. The episode's authors use language that is accessible to anyone with an interest in space and physics, ensuring that viewers are easily engaged and understand the complex and fascinating topic of black holes and event horizons. Black hole theory is challenging to understand fully, but the episode offers viewers an awe-inspiring, thought-provoking exploration of one of the universe's most intriguing mysteries.