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We don't know how the universe began, and we will never know

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Re: We don't know how the universe began, and we will never know

#71

Post by tsimionescu »

vouaobrasil wrote: post #48

I think one thing that humans have not come to terms with is the possibility that some fundamental fields are essentially dead in terms of possible new discoveries that most people will care about. That doesn't mean that there's nothing left to do. There are minor details in some fields but they are more like engineering problems. Physics may be one of those fields and I certainly think math is as well. However, it's…

Physics still has major gaps right in the middle - our two main theories of how the world works are mathematically incompatible. This leaves room for some significant new discoveries that could upend everyone's understanding of the world.

Not to mention that both QM and GR in themselves have inconsistencies or infinities. GR famously has a singularity in the center of a black hole, which means the math doesn't actually apply there. QM has the measurement problem, and the (probably related) problem of making the laws of motion linear, when we can clearly see highly non-linear behavior in reality.

Re: We don't know how the universe began, and we will never know

#72

Post by egello »

westcort wrote: post #69

We may not know the answer to how the universe began, but a time loop at the beginning of the universe is my favorite explanation. Gott and Li proposed this model and you can see Gott explain it elegantly here: https://youtu.be/raTqAyLikLU

The thing about time loop is that, how and when did it began? I just can't wrap my head around something being here, there and everywhere at all times.

Re: We don't know how the universe began, and we will never know

#73

Post by vouaobrasil »

galleywest200 wrote: post #68
vouaobrasil wrote: post #59

Earlier quoted context omitted.

Maybe, but if you look at the list of famous unsolved problems in math, it has been dwindling for a long time. The list used to contain problems that undergrads could understand. Biology is still like this -- you can take quite a few interesting unsolved problems in biology and explain it to most people. Math has a few left like the Riemann hypothesis, but the vast majority of new work that has been coming out is mor…

Are you suggesting there are no more unknown problems in mathematics, that "the list" will not be added to?

Well, due to the nature of math there are technically hundreds of questions you can ask (specific behaviour of the infinite number of diophantine equations, improving constants in estimation, whether there exists a prime number that satisfies XYZ, etc), but those problems are becoming so hyperspecialized that very few people if any will care about them. There may be one more paradigm shift that is related to stuff that Sholze is doing and there is certainly some work to do in proof theory ala Voevodky's univalent foundations so we could see a couple more things but the vast majority of basic foundational work in math is done.

So while we have a few more fundamental problems that most people have heard of like the Riemann hypothesis and the twin primes conjecture, don't expect to have any more of those. (Certainly the more recent ones are already so specialized that few people outside the immediate area would ever understand or even care about them).

I'm also not sure why there's such a negative view towards the end of progress on this site---a lot of people seem to take it as an axiom that currently "useless" things will eventually become useful but I simply do not believe that is the case (and this is coming from someone who has published quite a few papers in pure math).

Re: We don't know how the universe began, and we will never know

#74

Post by gcau »

Things like the big bang seem to be things after the beginning of the universe. In the same way, the issue with a god is "who created god, and who created that who created god...". If he's eternal, who/what made him eternal? We have the same problem in science, and I think any explanation/theory would have the same problem. Also, I dislike that when some physicists explain this they say, "sure, you can get something from nothing" and then change the definition of 'nothing' for their explanation to work. I feel like it's a disservice to not just admit mayyybe we don't know some things. Disclaimer: not a physicist and maybe missing something.

Re: We don't know how the universe began, and we will never know

#75

Post by ben_w »

egello wrote: post #72
westcort wrote: post #69

We may not know the answer to how the universe began, but a time loop at the beginning of the universe is my favorite explanation. Gott and Li proposed this model and you can see Gott explain it elegantly here: https://youtu.be/raTqAyLikLU

The thing about time loop is that, how and when did it began? I just can't wrap my head around something being here, there and everywhere at all times.

with time loops. It began half way though me writing this sentence — that's the thing

Re: We don't know how the universe began, and we will never know

#76

Post by pilaf »

734129837261 wrote: post #23

"We don't know how fire comes to life, and we will never know." "We don't know how to defend ourselves against beasts, and we'll never know." "We don't know how disease spreads, let's just hug it out, we'll never know." "We don't know how to fly like a bird, we'll never know." "We don't know how to land the booster of a rocket, we'll never know." "We don't know how to cure that form of cancer, and we'll never know."…

> We're likely inside an inescapable but observable simulation, inside a simulation, repeat for any unknown number of times. That's probably how "the universe" (our universe) began.

That's just deferring the question. If we're a simulation inside a larger universe, then how did that universe begin? Although I'd argue if we're in a simulation then we're still a part of the host universe, even if kept in isolation, and it's that host universe we should ultimately care about when asking the big questions.

Re: We don't know how the universe began, and we will never know

#77

Post by jessermeyer »

barrysteve wrote: post #70

Sabine likes to swing an axe into a tree. Her preaching gets tiresome fast though. She redefines science to require simplicity, when it simply doesn't require it. Many solved or solveable problems in science are ghastly complex and computers improved or solved them. The LHC is a most-obvious example for that category. Do I even need to point out the counter-arguments or are we just taking Sabine at her word.. This th…

> She redefines science to require simplicity, when it simply doesn't require it.

God wills the Universe into Being. I have explained everything completely. What qualities of a selection function do you have that would choose a different explanation?

One that doesn't require something more complex than the Universe to explain the Universe?

Re: We don't know how the universe began, and we will never know

#78

Post by mannykannot »

erlend_sh wrote: post #7

What we do know is that the universe didn’t begin from nothing . It’s impossible for something to arise out of nothing, so there has always been something . Nothingness is the space that holds everything. From there it can be argued that the universe began with the adjacent possible of nothing.

It is not obvious to me whether one could determine if the phrase "the adjacent possible of nothing" refers to something, as opposed to merely resembling phrases that do. Regardless, there is an evocative ring to it.
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