PBS Space Time Season 2016 Episode 2 When Time Breaks Down
- January 13, 2016
When Time Breaks Down is the second episode of the 2016 season of the PBS Space Time series. This episode takes a deep dive into one of the most fascinating and perplexing concepts in physics: time. Host Matt O'Dowd explores the ways in which time can appear to malfunction in certain situations and the implications this has for our understanding of the universe.
The episode begins with a primer on the standard measurement of time, derived from the rotation of the Earth and the oscillation of cesium atoms. From there, O'Dowd delves into one of the most famous thought experiments in the field of physics: the Twin Paradox. This involves one twin traveling at near-light speeds for a period of time while another twin remains stationary on Earth. When the traveling twin returns, they will have aged less than their Earth-bound sibling due to the effects of time dilation.
This concept leads into a discussion of the theory of relativity and how it fundamentally altered our understanding of time. O'Dowd explores the concept of spacetime, where time is treated as just another dimension alongside the three dimensions of space. He also discusses how the presence of large masses can distort spacetime, leading to phenomena like gravitational time dilation.
The episode then moves on to the topic of entropy and how it relates to the breakdown of time. Entropy is a measure of disorder in a system, and it is closely tied to the concept of the arrow of time. The arrow of time refers to the fact that time moves in a particular direction - from past to future - and that events tend to become more disordered over time. O'Dowd explains how this relates to the second law of thermodynamics, which states that the total entropy of a closed system can never decrease over time.
The breakdown of time is explored in several contexts throughout the rest of the episode. O'Dowd discusses how black holes challenge our understanding of time, as the intense gravitational forces they generate essentially halt the progress of time from an outside observer's perspective. He also talks about the Big Bang and the problem of cosmic inflation, where the universe expanded at an incredibly rapid pace in its earliest moments.
The episode concludes with a discussion of some of the most cutting-edge theories in physics, such as string theory and loop quantum gravity. These theories attempt to unify the fundamental forces of the universe into a single framework, but they also have profound implications for our understanding of time. O'Dowd discusses the concept of non-locality, where particles appear to be instantaneously connected across vast distances, and how this may relate to the idea of a timeless universe.
Overall, When Time Breaks Down is a fascinating exploration of one of the most perplexing concepts in the field of physics. O'Dowd does an excellent job of breaking down complex concepts into understandable terms, and the episode is sure to leave viewers with a newfound appreciation for the mysteries of time.
