Do Wormholes Break the First Law of Thermodynamics?

[magnemoe]

6 hours ago, K^2 said:

Honestly, what's happening inside the black hole's horizon is kind of a philosophical question. It's a bit like, "What happened before the big bang." Our physics is fully disconnected from whatever's on the other side.

The mathematical model that matches up with what's going outside of the rotating black hole is the Kerr metric. If we do pretend that it describes reality inside the black hole, then the singularity of a rotating black hole is ring-shaped - that is precisely a ring of zero thickness, rather than a donut - and it contains much of the black hole's angular momentum. The rest is in the "rotating" energy of the gravitational field itself.

The interior solution is unstable from perspective of an exterior observer, however, and has a lot of non-physical properties, like permitting time travel. So, you know, take all of that with a grain of salt. From our perspective, there's an event horizon, an ergosphere just below, and whatever's inside that has a lot of mass and a lot of angular momentum, and that's all that matters to a physical world in our universe.

Edit: Though, there's an interesting caveat. Unlike discussion of time-before-the-big-bang, theoretically speaking, with sufficiently massive black hole, such as the one at the center of our galaxy, you can travel into the interior and find out what that looks like and how it works. If Kerr metric is at all a reliable guide, after passing through both the outer and inner ergospheres, if your craft survived the radiation and had enough fuel to perform the necessary maneuvers, you can get past the inner event horizon, to emerge in some sort of the interior space that should be safe to navigate, and from your local perspective, will extend to infinity. That space is yours to explore, and you can learn all of the secrets of what lies within the black hole, But there is absolutely no way to come back to normal space to let us all know, nor send a message, nor in any way influence what's going on in our universe.

So maybe, instead, I should be comparing it to the afterlife, or something like it. It's a place you can go to, but nobody can come back from, and so we can't possibly know what's there.

I see, its also worth mention that mathematics is not reality. That an model who works mathematically does not imply its reality.
We can disprove negative length or negative eggs even if useful in math. Tachyons is harder to disprove.  
As an software developer x/0=0 would make far more than 99% more of divisions.

And the real question at the big bang as t=planck time 1 and some time later  the universe was an black hole. As you say math breaks at the event horizon. 

[farmerben]

The first law of thermodynamics is harder to disprove.  Before it breaks we will invent a heretofore unknown form of potential energy.

[RocketFire9]

On 1/20/2023 at 5:13 AM, K^2 said:

you can travel into the interior and find out what that looks like and how it works

Sounds like a bad sci-fi movie about earth being covered in dust storms and having to look for a new planet...
"Those aren't mountains!"

 

Spoiler

I'm not saying Interstellar is bad, I just think that part is unrealistic, even for Sci-Fi.

 

Edited January 24, 2023 by RocketFire9
edit

[K^2]

7 hours ago, RocketFire9 said:

Sounds like a bad sci-fi movie about earth being covered in dust storms and having to look for a new planet...

I don't know about a serious one, but it'd be a great setup for a horrible parody. "Yes, we found a suitable planet. Lets go back and let everyone on Earth know." - "Uh... Yeah, about that. We can only enter this space, not leave it." - "..." - "On retrospect, yes, a bad plan."

[MarcAbaddon]

Theoretically general relativity also allows for naked singularities, though there is the cosmic censorship hypothesis, which says this should not happen. But that's mainly because it would break causality. With a naked (rotating) singularity you would still have the ring-shape singularity, the time travel aspect and ability to get as close as you want to the singularity, but there would be event horizon meaning you can escape.

[kerbiloid]

A quickshovel fanshot.

Some soultions in the string theory presume that some dimensions (six or so) are looped.

If presume that the time dimension is looped, too, then no causality limitations seem being reasonable.
You just need to wait a little to reach the "past".

Then we can enjoy time machines, naked singularities, trips into the past, the future prophecies...

Spoiler

 

[K^2]

15 hours ago, MarcAbaddon said:

Theoretically general relativity also allows for naked singularities

None of the known solutions are stable, and there are some strong mathematical conjectures suggesting a stable solution isn't possible. That said, an unstable state can still be usable, so there are some interesting possibilities there. However, one should keep in mind that it's the sort of place where quantum gravity starts to play a role, and we do not have a mathematical framework for that which can be used in any practical sense. (We do, technically, have a governing equation for quantum gravity, but it's in a form where it's basically "infinity = infinity", which isn't terribly useful.  And nobody so far has been able to figure out how to fix that.)