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Are Black Holes Actually Dark Energy Stars?

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Re: Are Black Holes Actually Dark Energy Stars?

#111

Post by everdev »

jboggan wrote: post #85
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.

It's interesting, original, and most importantly falsifiable. There will be real differences between the jets predicted by his theory and the commonly accepted model, I'm excited to see it tested. There's a moment at which every scientific theory is only thought credulous by a single person.

> There's a moment at which every scientific theory is only thought credulous by a single person.

Agreed, but the same is also true of any conspiracy theory or half-baked idea. The theory should be evaluated on it's merits, not the number of supporters. And theories that can be tested are always better than ones that can't IMO.

Re: Are Black Holes Actually Dark Energy Stars?

#112

Post by dsnuh »

codethief wrote: post #97
dsnuh wrote: post #94

Earlier quoted context omitted.

I just realized I was replying to the wrong parent comment! So sorry. I was talking about a PBS Space Time episode on YouTube I saw in (or came across via) a different comment. https://youtu.be/KePNhUJ2reI

No worries, I hadn't watched the video yet, anyway. :) So feel free to rephrase your questions if you like!

My questions were based in the video I linked above, which it sounds like may be incorrect in the way it presents the topic?

Re: Are Black Holes Actually Dark Energy Stars?

#113

Post by chadcmulligan »

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…

A genius by the name of Kanye was proposing this recently, though his work to, isn't widely accepted.

Re: Are Black Holes Actually Dark Energy Stars?

#114

Post by scythe »

The big giant glaring hole in his theory is that the total mass of all the black holes in the Universe is WAY less than the amount of dark energy. It's like claiming that the Pacific Ocean was filled in by the Sacramento River. That's why scientists aren't taking it seriously.

Re: Are Black Holes Actually Dark Energy Stars?

#115

Post by Sarki »

Trombone12 wrote: post #76
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.

Actually, as far as I get it, black holes just don't exist: it's a journalist term coined for a mathematical concept. In short a black hole is how we call the possible existence of a place in the universe where there is no time nor energy, but it's no more than a mathematical possibility in the end as these are common variables in astrophysics.

Re: Are Black Holes Actually Dark Energy Stars?

#116

Post by econnor »

joe-collins wrote: post #17
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.

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…

There's a certain nominative-deterministic inevitability to all this. There are these things called black holes that apparently are a full of a lot of stuff and aren't completely understood. And there's this mysterious stuff called dark matter that has to exist but seems to be hiding. My mom would be yelling "'Come on guys, join the dots". And who would blame her.

Re: Are Black Holes Actually Dark Energy Stars?

#117

Post by chriswarbo »

blurbleblurble wrote: post #109

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.

> dark energy is only dark because it doesn't interact electromagnetically

That's certainly the case for dark matter. After decades of work we still don't know what it is, which has given the word "dark" the additional meaning of 'unknown'.

When it comes to dark energy, I think it mostly implies this second meaning.

Re: Are Black Holes Actually Dark Energy Stars?

#118

Post by chriswarbo »

Sarki wrote: post #115
Trombone12 wrote: post #76

Earlier quoted context omitted.

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

Actually, as far as I get it, black holes just don't exist: it's a journalist term coined for a mathematical concept. In short a black hole is how we call the possible existence of a place in the universe where there is no time nor energy, but it's no more than a mathematical possibility in the end as these are common variables in astrophysics.

Black holes exist, in the sense that we have observed several phenomena that can be easily explained by the presence of a black hole, but which couldn't be explained otherwise. For example the orbits of stars around Sagittarius A* ( https://en.wikipedia.org/wiki/Sagittarius_A* ) and the X-ray emmission of Cygnus X-1 ( https://en.wikipedia.org/wiki/Cygnus_X-1 ).

> In short a black hole is how we call the possible existence of a place in the universe where there is no time nor energy

I don't know where you got this idea, but black holes don't have "no time" and they contain lots of energy (often several stars' worth).

Keep in mind that time is relative, so when talking about extreme situations like black holes it's important to keep track of what we're talking relative to. In particular, if an astronaut left a space ship, approached a black hole, passed beyond the event horizon and carried on going, that astronaut wouldn't really notice: if they looked forwards into the black hole they'd just see normal looking space, if they looked backwards they'd see their ship just as if they'd not entered the black hole. Relative to the astronaut, space and time appear completely normal; hence it doesn't make sense to talk about black holes having "no time".

Things would look different relative to the ship: the image of the astronaut they see would redshift as it approached the event horizon, and would also slow down until it came to a stop when at the horizon.

Note that this ignores tidal forces, which can be large around small black holes (the astronaut would certainly notice if their body were torn apart!). For large black holes like Sagittarius A* the tidal forces at the event horizon should be small enough to ignore.

Re: Are Black Holes Actually Dark Energy Stars?

#119

Post by mrpgraae »

everdev wrote: post #111
jboggan wrote: post #85

Earlier quoted context omitted.

It's interesting, original, and most importantly falsifiable. There will be real differences between the jets predicted by his theory and the commonly accepted model, I'm excited to see it tested. There's a moment at which every scientific theory is only thought credulous by a single person.

> There's a moment at which every scientific theory is only thought credulous by a single person. Agreed, but the same is also true of any conspiracy theory or half-baked idea. The theory should be evaluated on it's merits, not the number of supporters. And theories that can be tested are always better than ones that can't IMO.

The thing about conspiracy theories is that they are usually not falsifiable, at least not to their proponents.

As jboggan mentions, this theory is both falsifiable and testable in practice.

I think it's important that there are always a few people in science who go against the mainstream, as long as they do actual science, so falsifiable and testable theories.

Re: Are Black Holes Actually Dark Energy Stars?

#120

Post by Sarki »

chriswarbo wrote: post #118
Sarki wrote: post #115

Earlier quoted context omitted.

Actually, as far as I get it, black holes just don't exist: it's a journalist term coined for a mathematical concept. In short a black hole is how we call the possible existence of a place in the universe where there is no time nor energy, but it's no more than a mathematical possibility in the end as these are common variables in astrophysics.

Black holes exist, in the sense that we have observed several phenomena that can be easily explained by the presence of a black hole, but which couldn't be explained otherwise. For example the orbits of stars around Sagittarius A* ( https://en.wikipedia.org/wiki/Sagittarius_A* ) and the X-ray emmission of Cygnus X-1 ( https://en.wikipedia.org/wiki/Cygnus_X-1 ). > In short a black hole is how we call the possible exis…

Thanks for the clarification, perhaps I was misleading, the point being that black holes have been deduced by mathematical interpretation, not observation of a phenomenon and today as per your own example we're still trying to find proof of their existence.

On the other hand, based on my understanding of the Janus model as I said in my first comment, the location of the seemingly void places are actually explained by the concentration of antimatter, which repulses matter through gravity. A possibly wrong summary of what I'm visibly struggling to communicate: This model explains how on the same way matter concentration attracts matter and rejects anti-matter, antimatter concentration attract antimatter and rejects matter.

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