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Research suggests Big Bang may have taken place inside a black hole

port.ac.uk

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Re: Research suggests Big Bang may have taken place inside a black hole

#331

Post by chucksmash »

lukas099 wrote: post #265
johnisgood wrote: post #236

Earlier quoted context omitted.

Most jobs are really not important either, they just keep people busy. Do you need sources for this claim, too?

Yes. Who are these people paying for jobs that don't do anything, and why are they more concerned about "keeping people busy" than their own profits?

It's like saying "if you know half of your advertising dollars are wasted, why don't you just cut your ad buy in half?"

I still remember the joke from my first job:

Q: How many people work at this office?

A: About half.

Re: Research suggests Big Bang may have taken place inside a black hole

#332

Post by pontifier »

EasyMark wrote: post #219
pontifier wrote: post #107

There was a youtube lecture I saw years ago that showed exactly what you'd see as you fell into a black hole and passed through the event horizon. You'd see EVERYTHING that EVER crossed the event horizon. But critically, you'd see it EXACTLY as it was at the monent it crossed. Sounds a bit crowded to me. Sounds a bit like I'd expect the big bang to look.

I thought you were supposed to get spaghettified and die instantly ?

At the event horizon of a large enough black hole, the tidal difference in gravity between your toes and head shouldn't be noticeable. There shouldn't actually be anything special about falling through the event horizon when looking at yourself.

Outside though, you'd see everything start to blue-shift. Things below you would blue shift back to normal, and the universe above you would blue-shift and speed up until you'd see the heat death of the universe. Anything falling in after you would red-shift again as it approached to match your "normal" rate of time. Critically this would include any light or other particles, so it might be very hard to survive.

No matter how fast you go or how weird the space time you are in, your local clock should still tick steadily to you, and you wouldn't notice anything weird.

Re: Research suggests Big Bang may have taken place inside a black hole

#333

Post by mousethatroared »

meindnoch wrote: post #101

I've read somewhere an article which posited that our 3D universe might be inside a 4D black hole. When you cross a black hole's event horizon, the radial coordinate becomes timelike, so you lose one degree of spatial freedom. Movement is still possible in the tangential directions however, so what you get is basically an N-1 dimensional universe. So maybe our 3D universe is actually matter that fell into a 4D black…

You can't have the curl operator in 4D.

Re: Research suggests Big Bang may have taken place inside a black hole

#334

Post by pontifier »

pontifier wrote: post #107

There was a youtube lecture I saw years ago that showed exactly what you'd see as you fell into a black hole and passed through the event horizon. You'd see EVERYTHING that EVER crossed the event horizon. But critically, you'd see it EXACTLY as it was at the monent it crossed. Sounds a bit crowded to me. Sounds a bit like I'd expect the big bang to look.

Found the lecture. Here is a link to the appropriate part: https://youtu.be/BdYtfYkdGDk?si=iNHi7N68DHxT-52-&t=3182

Re: Research suggests Big Bang may have taken place inside a black hole

#336

Post by layer8 »

emigre wrote: post #76
layer8 wrote: post #49

Earlier quoted context omitted.

Many-worlds doesn’t predict that everything happens somewhere; far from it.

Well, it's just a joke. :) It doesn't necessarily have to make a lot of sense. In any case, I find your comment very interesting. I'm studying quantum computing at the moment, and I've had to read the different interpretations of quantum mechanics, including Everett's many-worlds interpretation. As a non-physicist, I've found the different interpretations fascinating. The many-worlds one, as far as I understood it, s…

The many-worlds theory says that the time-evolution of the (universal) wave function according to the Schrödinger equation is what's real. Different "slices" ("branches") of the wave function correspond to different "worlds". (A "world" is basically defined by what is quantum-entangled together.) The wave function thus decomposes into the different worlds.

Collapse theories, in contrast, state that at specific points in time (the "measurements"), the wave function stops following the Schrödinger equation, and instead collapses to a single slice/branch/world, thus upending the natural proliferation of branches implied by the normal time-evolution of the wave function according to the Schrödinger equation.

Even in many-worlds, however, the wave function doesn't necessarily contain all conceivable worlds. It only contains the worlds, following from some initial quantum state, that follow from the Schrödinger equation. While it's true that all possible outcomes of a quantum measurement become real (because they are all contained in the wave function in superposition), "possible" here means specifically what the equations allow, not any imaginable world.

Re: Research suggests Big Bang may have taken place inside a black hole

#337

Post by pontifier »

pontifier wrote: post #332
EasyMark wrote: post #219

Earlier quoted context omitted.

I thought you were supposed to get spaghettified and die instantly ?

At the event horizon of a large enough black hole, the tidal difference in gravity between your toes and head shouldn't be noticeable. There shouldn't actually be anything special about falling through the event horizon when looking at yourself. Outside though, you'd see everything start to blue-shift. Things below you would blue shift back to normal, and the universe above you would blue-shift and speed up until you…

-Just watched the lecture again, and you wouldn't actually see the outside universe speed up.

Re: Research suggests Big Bang may have taken place inside a black hole

#338

Post by mjh2539 »

kibwen wrote: post #61
twodave wrote: post #51

Earlier quoted context omitted.

Might as well believe in God if you’re going to believe in spontaneous accidental creation…

Why not? If you can't observe it, test it, and reproduce it, then it lies outside the realm of science and in the realm of belief. Until someone figures out a way to experimentally verify the big bang hypothesis (or any other explanation for the origin of the universe or what came "before"), it's entirely fair to attribute it to whatever you feel like, be it a god or anything else. There is no law of the universe tha…

If you can't observe it, test it, and reproduce it, then it lies outside of the realm of (natural) science and may lie within the realm of mathematics, philosophy, or (gasp) theology.

> There is no law of the universe that guarantees that science is capable of answering all questions.

There's a name for a more nuanced version of this "law" and there's a good amount of work being done arguing for and against weaker and stronger versions of it: https://plato.stanford.edu/entries/sufficient-reason/

Re: Research suggests Big Bang may have taken place inside a black hole

#339

Post by layer8 »

asveikau wrote: post #63
layer8 wrote: post #46

Earlier quoted context omitted.

That doesn’t affect time in the sense discussed here, though, which is a fundamental dimension in our physical theories.

It's been several years and I'm not fresh enough to summarize it, but some time ago I read Carlo Rovelli's "The Order of Time" which is a pop science book on why that isn't true. Ymmv. I'm sure many reading this know more than I do about the topic.

Carlo Rovelli's book is idiosyncratic, it doesn't reflect scientific consensus on the matter.
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