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Are Black Holes Actually Dark Energy Stars?

nautil.us

41–50 of 129 posts

Re: Are Black Holes Actually Dark Energy Stars?

#41
post #11

Earlier quoted context omitted.

After all the big discoveries (and personalities) of the 20th century, physics has seemed to be relatively quiet lately. So people are eager for the next big and dramatic change to our understanding. And that's what George Chapline is offering the pop sci press.

If what LIGO achieved is not loud enough for the 21st century, then we are probably doomed. It is a NEW kind of telescope that has not even been utilized for 1% of its potential. PS: I'm not arguing with your statement, you have all the right to think that way. Maybe even people who lived during Einstein's earlier times thought the same for their previous century.

Yes, and there are also neutrino telescopes. I wait for the detection of an high energy neutrino event from beyond the CMBR. I think the opportunity, our understanding of physics and technology give us right now are immense. The fact that general relativity and quantum mechanics havent been reconciled by now only means that this is probably a very hard thing to do. But it doesn't mean that 'phyics is dead'.

[0]: https://icecube.wisc.edu/

Re: Are Black Holes Actually Dark Energy Stars?

#42
post #15

Earlier quoted context omitted.

Question if you don't mind. This "information being destroyed" thing. What do they mean by information? Isn't information a human construct? How is the universe supposed to know what information is?

A fun way to imagine it is with Maxwell's Demon. https://en.wikipedia.org/wiki/Maxwell%27s_demon That is an example of one way in which information can be exchanged for work.

This is me being dense, but I don't see the connection to parent's question. Is it that the demon uses information (the speed of the particles?) to perform work (decrease entropy)? But also not really, bc that would violate the 2nd law of thermodynamics? I understood parent's question to be what the heck does "information" mean in this context to begin with. My question too, because I'm pretty sure I've got the wrong answer myself.

Re: Are Black Holes Actually Dark Energy Stars?

#43
post #25
post #14

We have people like string theorists thinking about higher dimensions in space. It occurred to me the other day when the dark matter article hit the front page that our equation for gravity works with three dimensions but those dimensions are uniform. I can turn an object with very little effort (literally without doing work) and it’s the same size from our perspective. How would it work if matter has more dimensions…

Yea that's a part of the string theoretic calculation, that some of these higher dimensions are different than the three we're accustomed to. They're curved and swirled and weird. It's pretty unclear that they're real, but it's an interesting idea

Indeed. The usual layman example is that a string has two dimensions when you're close enough to it that it resembles a cylinder, but only one when you zoom out far enough that it becomes a line.

Re: Are Black Holes Actually Dark Energy Stars?

#44
post #2

I've seen a couple of articles about this guy recently and they both struck me as weirdly credulous given the apparently complete lack of evidence supporting his theory and the fact that approximately no other scientists seem to find it credible.

> The idea has found no support in the astrophysical community They put it pretty bluntly in the article.

That's true, but the article as a whole still felt weirdly credulous to me. The reminders that this is a complete flight of fancy work out to like one or two clauses in a 1400-word article that devotes a lot of room to detailing his theory and repeatedly pointing out that it could theoretically be proven true someday.

To this article's credit, though, it is more measured than others. Just as a whole it seems weird to me how much attention such a seemingly insignificant hypothesis is getting.

Re: Are Black Holes Actually Dark Energy Stars?

#45
post #32
post #30

Earlier quoted context omitted.

PBS Space Time did a recent episode on higher spacial dimensions and gravity. https://www.youtube.com/watch?v=3HYw6vPR9qU

The delivery on this program is extremely annoying and slow paced (and rushed on points that ought be slow). :(

It's designed to be watched at 1.5x speed

then it sounds like normal speech.

Re: Are Black Holes Actually Dark Energy Stars?

#46

Found an interesting technical summary/critique of these ideas https://motls.blogspot.com/2005/03/chapline-black-holes-dont...

Lubos is interesting to read at times - even brilliantly enlightening at times. But keep in mind that he's an unapologetic ultra-conservative and climate change denier, as well as an occasional troll, in addition to being a reputable string physicist. He expresses stronger views than he probably should on no shortage of topics.

Re: Are Black Holes Actually Dark Energy Stars?

#47
post #8
post #6

Earlier quoted context omitted.

Outside observers never see the material cross the horizon, ever. That's why it's called a horizon, you'll never reach it (from the pov of an outside observer). Growth-wise, you have to keep in mind that the black hole doesn't grow when matter crosses the horizon, but when the matter gets close enough to the horizon that mass of black hole + mass of new matter creates a blackhole of a larger radius that encompasses t…

How would you ever observe black hole to grow/accreate matter then?

You can indirectly measure it's mass, charge, and angular momentum.

Re: Are Black Holes Actually Dark Energy Stars?

#48

Earlier quoted context omitted.

I would argue that one of the reasons why physics news has been quiet is because the state of the field has moved beyond a lay person's understanding at more than a high level.

If you can't explain your idead to your janitor, you don't really grasp them yourself.

I agree with your statement, but we're discussing physics reporting in the news. They are aiming for eyeballs and ad clicks, not for emanating understanding of the topic.

Re: Are Black Holes Actually Dark Energy Stars?

#49
post #14

We have people like string theorists thinking about higher dimensions in space. It occurred to me the other day when the dark matter article hit the front page that our equation for gravity works with three dimensions but those dimensions are uniform. I can turn an object with very little effort (literally without doing work) and it’s the same size from our perspective. How would it work if matter has more dimensions…

> I can turn an object with very little effort (literally without doing work) and it’s the same size from our perspective. I can't reproduce your experiment... I tried turning a piece of paper. At first it looked, say, about as large as a cantaloupe, but when I turned it got smaller and smaller until it practically disappeared, and it becomes very tiny... basically nothing more than a thin line in space. At certain a…

Some objects have axes of symmetry, right? Think of a disk or a cylinder or a sphere. You can rotate these on some axes without a change in shape. This concept extends to higher dimensions. Not that I agree with the first poster's point necessarily.

Re: Are Black Holes Actually Dark Energy Stars?

#50
post #37
post #10

Earlier quoted context omitted.

Infalling matter or radiation becomes ‘simply’ infinitely red-shifted (on account of the slowed time), and hence undetectable to an external observer — and is hence indistinguishable from the bulk of the prior-existing “black hole proper”.

Conversely, a particle on the surface of an object compressed to near its Schwarzschild radius should experience an extreme blue shift and time contraction. Imagine absorbing in one instant a billion years of microwave background radiation blue shifted to gamma and beyond. How could the near-black-hole hang onto it?

Inside of a black hole doesn't hang on to anything. There is simply no longer a direction that points out.
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