3 ms·

This feels relevant: Roger Penrose - Why Did Our Universe Begin? https://www.youtube.com/watch?v=ypjZF6Pdrws https://www.youtube.com/watch?v=ypjZF6Pdrws tl;dw:

This feels relevant: Roger Penrose - Why Did Our Universe Begin? https://www.youtube.com/watch?v=ypjZF6Pdrws https://www.youtube.com/watch?v=ypjZF6Pdrws tl;dw: It is well known that the universe expands, tracing this back in time leads to the singularity called the Big Bang. But is it possible to ask for a "before" the beginning of time? What is time? Time is what we measure with clocks. What are clocks? Something that returns to the same state (say, a pendulum, or the earth orbiting around the sun - a "year"). To be able to build a clock you need mass. Only objects with mass, moving below the speed of light, experience time. In the very far future, after all stars have burned out, the only objects remaining will be black holes. Eventually, even they will decay due to Hawking radiation. So in the end, there will be only expanding space, and radiation that "travels to infinity". Photons themselves do not experience time as they move with the speed of light. Without mass, without anything that has a notion of time, the concept of distance becomes meaningless. The universe will become spacelike. Without distances, the universe may as well be a singular point. Like the Big Bang :)

wruza 4y ago
This brings questions. How the universe knows it’s “over”, or how the last BH knows it shouldn’t start a cycle yet? Sounds as if the universe was some database which compacts itself when a column becomes all-equal and then adds another one after seeing that there is too much E in zero/undef distance. Does that create more than one big bangs? (Since distances are undefined, nothing wrong with assuming anything from zero to just below +inf apart.) Edit: I think we should see time only as a parameter and find out how any calculation could work without it. That would relax the past tense (what “was” before time) into something manageable (no linguistic analogy yet).

wruza 4y ago

This brings questions. How the universe knows it’s “over”, or how the last BH knows it shouldn’t start a cycle yet? Sounds as if the universe was some database which compacts itself when a column becomes all-equal and then adds another one after seeing that there is too much E in zero/undef distance. Does that create more than one big bangs? (Since distances are undefined, nothing wrong with assuming anything from zero to just below +inf apart.) Edit: I think we should see time only as a parameter and find out how any calculation could work without it. That would relax the past tense (what “was” before time) into something manageable (no linguistic analogy yet).