PBS Space Time Season 2019 Episode 37 Can You Observe a Typical Universe?

PBS Space Time season 2019 episode 37, titled "Can You Observe a Typical Universe?", dives deep into the notion of observing the universe and whether there is such a thing as a "typical universe." Host Matt O'Dowd explores the complexities of studying the universe and how it can be difficult to generalize findings to the entire cosmos.

O'Dowd starts by discussing how we observe the universe through telescopes and how the data we gather can be misleading. He explains that we can only observe the light that reaches us, which means there could be a lot of hidden matter and energy that we can't see. O'Dowd also notes that different parts of the universe are at different distances from us, so we're actually seeing different parts of its history.

The show then delves into How scientists try to make sense of these complications by using simulations to create virtual universes. O'Dowd explains that these simulations take the laws of physics and apply them to a hypothetical universe to see what would happen. The simulations can offer insight into how things like galaxies form and how dark matter affects the universe.

However, O'Dowd brings up the fact that these simulations aren't perfect. They're based on assumptions and can only mimic so much of the complexity of the universe. As a result, it's difficult to say whether a simulated universe is actually representative of the entire cosmos.

The episode also explores the concept of the "observable universe" and how that changes depending on the observer. O'Dowd explains that because the universe is expanding, we can only observe a certain distance from us. Moreover, different observers will have different observations of the observable universe. This can lead to variations in what we consider to be a "typical universe."

Additionally, the episode touches on the fact that our current understanding of the universe is based on observations of its most visible constituents - stars and galaxies. There could be entire subclasses of objects or phenomena - which we are yet to discover - that could be significant in making the universe 'typical.'

Through this episode, O'Dowd touches upon how science has a long way to go in understanding the universe, and that made it much more challenging to establish a "typical" universe. While scientists can study and simulate the universe, observing everything within the universe is currently impossible. Nonetheless, the show presents a thought-provoking discussion about the complexities of observing and studying the universe.