PBS Space Time Season 2015 Episode 32 Does Dark Matter BREAK Physics?

In this episode of PBS's Space Time, the question of whether dark matter breaks physics is explored. Dark matter is a mysterious substance that makes up approximately 85% of all the matter in the universe. It cannot be seen, detected, or interacted with through any of the known forces of nature. Despite its evasiveness, scientists have been able to measure the effects that dark matter has on surrounding matter, such as stars and galaxies.

However, the existence of dark matter poses a challenge to our current understanding of physics. The Standard Model of particle physics, which describes all the known elementary particles and their interactions, does not include a particle that could account for dark matter. Some theories suggest that dark matter could be made up of particles that have yet to be discovered, while others suggest that our understanding of gravity is incomplete and needs to be modified.

The episode delves into the various theories about dark matter, including the idea that it could be made up of Weakly Interacting Massive Particles (WIMPs), axions, sterile neutrinos, or even primordial black holes. Scientists are currently searching for evidence of these particles through experiments using particle accelerators, underground detectors, and even satellites.

The episode also discusses the possibility that dark matter could be a manifestation of modified gravity. The prevailing theory of gravity, Einstein's General Theory of Relativity, has been incredibly successful in explaining the behavior of gravity in our solar system and beyond. However, it starts to break down when we consider very large scales, such as the behavior of galaxies and galaxy clusters. Modified gravity theories attempt to solve this problem by modifying Einstein's equations on these large scales.

The episode also touches on the recent controversy surrounding the discovery of a galaxy that seems to be almost entirely made up of dark matter. The discovery has been seen by some scientists as evidence that traditional models of physics may need to be revised if dark matter is to be explained.

Overall, the episode offers an in-depth exploration of the mystery of dark matter and how it challenges our current understanding of physics. It provides a glimpse into the ongoing efforts of scientists to solve one of the biggest mysteries of the universe.