The Evening Universe
The Evening Universe
Calm science for your evening
Long, relaxing videos about the biggest questions in the universe, told at a gentle pace and in plain language.
Latest episode
Faster-than-light travel is time travel – Einstein knew it in 1907
If anyone, by any means, could travel faster than light, they could also travel into the past. Albert Einstein described this back in 1907 in a short thought experiment. This episode walks through, step by step, how speed turns into time travel, and why it looks as if nature is doing everything it can to stop it.
Along the way: the clocks on GPS satellites, Einstein's train, Roger Penrose's Andromeda paradox, the tachyons nobody has ever found, the 2011 “faster-than-light neutrinos” mystery, warp drives, wormholes, and Stephen Hawking's party that no time traveller ever attended.
Chapters
- Introduction
- How fast is light, really?
- Why we can never catch up
- The proof ticking in your pocket
- When is now?
- Two passers-by and a distant galaxy
- The rule that is never broken
- A letter to the past
- The answer that comes before the question
- The particle nobody found
- Loopholes in spacetime
- How nature defends itself
- What does it all mean?
What to expect
You can follow along without equations or background knowledge, while driving, working or falling asleep.
Every episode takes one big question and stays with it for the better part of an hour. We explain everything at a gentle pace and in plain language, and any unusual term is explained the moment it comes up.
Every claim is checked against reliable sources, and on debated questions we tell you where solid knowledge ends.
- Time and time travel
- The speed of light
- Quantum physics
- Parallel universes
- The mystery of consciousness
- The history of science
Where the facts come from
Each episode lists its sources in the video description. For the faster-than-light episode, these were among them:
Einstein's 1907 thought experiment and Tolman's 1917 description; the Hafele–Keating experiment (1971); the Frisch–Smith muon measurement; Penrose, The Emperor's New Mind (1989); Feinberg (1967); the OPERA experiment (2011–2012); Alcubierre (1994); Morris, Thorne and Yurtsever (1988); Hawking (1992); Novikov; Gödel (1949).
New videos every week
Subscribe on YouTube and the next episode will be waiting for you. Got a question or a topic idea? Leave it in the comments under any video.