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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?

#101

Post by franciscrick1 »

chc wrote: post #44
empath75 wrote: post #28

Earlier quoted context omitted.

> 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…

Did you want them to say "This guy is a crank!" several hundred times to fill up space? How are we ever supposed to learn anything new if everything is run through your hypothetical credibility filter first?

Re: Are Black Holes Actually Dark Energy Stars?

#103

Post by Retra »

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.)

>The idea that space and time are actual objects, instead of intellectual constructs, has always struck me as wrong.

There were similar objections to the existence of the electromagnetic field, back in the 1890s. But it turns out that fields can propagate energy independent of any non-field objects in them... and if it can carry energy, then how can you say they aren't real?

Spacetime carries energy in the form of gravitational waves. So it is as much an object as anything else that carries energy, whether it be in wave form or mass form.

Re: Are Black Holes Actually Dark Energy Stars?

#105

Post by sulam »

zoggenhoff wrote: post #102

What is dark energy?

When you sum up all the red shifts of a large piles of galaxies they are receding from us at speeds faster than can easily be explained using the Hubble model. One theory for this is a repulsive energy of a form we have not yet observed, dubbed "dark energy", which is purported to be causing accelerating expansion of the universe since the Big Bang. More here:

https://en.wikipedia.org/wiki/Dark_energy

Re: Are Black Holes Actually Dark Energy Stars?

#106

Post by whatshisface »

bacon_waffle wrote: post #88
maze-le wrote: post #41

Earlier quoted context omitted.

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]: http…

> I wait for the detection of an high energy neutrino event from beyond the CMBR My (non-physicist) understanding of this, is that neutrinos from then will be quite low energy now, due to the expansion of the universe(?), and so not detectable by the method IceCube uses. There is a minimum energy required, in part because the charged particles generated by the neutrino interaction need to be moving faster than the sp…

The neutrinos may start out with any energy, whatever produced them will determine that. To cross the great expanse of time and redshifting due to expansion and still have a lot of energy left, they would simply have to start out with a whole lot more. Any neutrino event that we could detect from that far away would probably be massive anyways, so maybe we'll see something.

Re: Are Black Holes Actually Dark Energy Stars?

#107

Post by whatshisface »

admax88q wrote: post #64
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.

The thing I hate about this statement is it gives people an excuse to ignore things they don't understand at first glace by claiming the presenter doesn't fully understand it so it's probably not true. Its a good standard to hold yourself to when explaining things to others. But not one to hold others to when explaining to you.

"Be liberal in what you accept but conservative in what you generate."

Re: Are Black Holes Actually Dark Energy Stars?

#108

Post by whatshisface »

klodolph wrote: post #40
hinkley wrote: 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…

The distance between any two ink dots remained constant as you rotated the paper, which is what you would expect when the metric is x^2+y^2+z^2. If the "dimensions were not uniform," then the same transformation may alter the distances. Perhaps the parent is on their way to discovering relativity.

Re: Are Black Holes Actually Dark Energy Stars?

#109

Post by blurbleblurble »

The thing is, dark energy is only dark because it doesn't interact electromagnetically, whereas black holes are dark because the light gets trapped. So these are very different concepts.

I think it's fair to say black holes are a kind of "star", but the concept of dark energy and dark matter are something else.

Re: Are Black Holes Actually Dark Energy Stars?

#110

Post by vnorilo »

doombolt wrote: post #39
HalcyonicStorm wrote: post #35

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.

If you can successfully eli5, that indicates thorough mastery of a subject. Stuff on the bleeding edge of physics can be grasped by a limited group of experts, but nobody might have developed the 10th dan sensei level understanding yet. Maybe in 50 years we'll have great explanations of black holes and quantum mech that laypeople can grok.
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