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Are Black Holes Actually Dark Energy Stars?

nautil.us

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Re: Are Black Holes Actually Dark Energy Stars?

#71

Post by Semiapies »

empath75 wrote: post #28
chc wrote: 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.

It's just an aside they throw out before going into how This One Maverick's ideas are so exciting. And ultimately, they're still writing yet another article on the idea because it sells.

Re: Are Black Holes Actually Dark Energy Stars?

#72

Post by doombolt »

HalcyonicStorm wrote: post #48
doombolt wrote: post #39

Earlier quoted context omitted.

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.

One can read Wikipedia as well

Re: Are Black Holes Actually Dark Energy Stars?

#73

Post by aroberge »

philipov wrote: post #61
lottin wrote: post #53

"The fabric of space-time" — I hear this a lot, but what does it mean? Does it mean that space and time are a "fabric"? What is such a fabric made of? The idea that space and time are actual objects, instead of intellectual constructs, has always struck me as wrong. (I'm not a physicist.)

It's usually referred to as a fabric because in general relativity, spacetime is dynamic, as if it were on a fabric that could stretch and contract in response to the density of matter occupying it. This is where the rubber-sheet analogy comes from. As for what it is made of, that is one of the great open questions in theoretical physics right now, but also possibly where the analogy breaks down. Because of Lorentz I…

> However, because our world is cosmological and the big bang does actually pick out a preferred reference frame, Lorentz Invarience has to be approximate in some way.

A particular solution to a set of equations does not usually have all the symmetry of the equations. In fact, I would say that, any solution to GR equations with energy and/or matter (assuming homogeneity on large enough scale) you will find something that looks like a preferred frame of reference.

Re: Are Black Holes Actually Dark Energy Stars?

#75

Post by [deleted] »

empath75 wrote: post #28
chc wrote: 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.

[deleted]

Re: Are Black Holes Actually Dark Energy Stars?

#76

Post by Trombone12 »

Sarki wrote: post #52

On another note a theory which seems to fit particularly well is called Janus. The concept lies in the existence of a twin universe (ours being matter based the twin being antimatter based) merged together where the black holes are basically where the antimatter is concentrated and thus repulses all the matter hence this seemingly void. This is a succint summary but I hope it makes sense to the more knowledgeable rea…

That makes no sense, black holes are like super much the opposite of a void. Further, repulsion is precisely the opposite of gravity.

Re: Are Black Holes Actually Dark Energy Stars?

#78

Post by philipov »

Semiapies wrote: post #68
joe-collins wrote: post #17

Earlier quoted context omitted.

At least at the pop-science level, his ideas connect a lot of dots. He'd neatly resolve the weirdness and mystery of black holes, their jets, their information paradox, and dark energy. It feels good. Whether or not any of it makes a lick of sense once you start actually crunching numbers is another question. The lack of interest from other scientists leaves me skeptical (even if I'm silently enamored of the neatness…

Yep. I've been hearing mentions of this guy's theories from pop science publications for years even though, as the article says, "The idea has found no support in the astrophysical community—over the last decade, Chapline’s papers on this topic have garnered only single-digit citations." The pop science press is depressingly bad.

"Dark Energy Star" is pure marketing speak, and the pop science press loves sexy terms like that, whereas to serious physicists a hyphy phrase like that is going to throw all sorts of red flags, the same way an engineer would be appalled by someone boasting about Chaos Engineering. It's usually referred to as the Cosmological Constant instead.

Re: Are Black Holes Actually Dark Energy Stars?

#79

Post by m4x »

pmalynin wrote: post #66
russdill wrote: post #55

This seems to try and make a parallel between neutron stars and his proposal of a "dark energy star". This uber-dense matter would stop matter from collapsing enough to form an event horizon. But there is a serious problem with this. If you measure the density of a black hole by using it's even horizon you'll find that the mass and event horizon do not scale together. For instance, calculated in this way, a galactic…

It actually is true thought, that some supermassive blackholes have a density thats pretty close to that of water, and their event horizons are very very gentle.

I think this is only the case if you consider the mass density to be uniform within the event horizon, which isn't true.

Re: Are Black Holes Actually Dark Energy Stars?

#80

Post by qubex »

mcbits wrote: post #37
qubex wrote: 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?

Yeah... basically looking backwards from the perspective of an infalling particle one would experience the full blast of the Big Bang as it occurred ‘originally’.
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