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A Physicist Who Denies Dark Matter

nautil.us

81–90 of 182 posts

Re: A Physicist Who Denies Dark Matter

#81
post #76

Earlier quoted context omitted.

Acceptance doesn't dismiss theories, evidence does. A physicist shouldn't truly deny anything, just look at the evidence and say it is not the best theory. Even with a better explanation, we can't be sure more information won't see the return of dark matter. Milgrom should understand this well, he's suggesting the return of the cosmological constant.

Forget dark matter, use the analogy from the article: afaik nobody has ever proven ether is not existing. I know nothing about dark matter, but I could play a zero-sum game based on this article content - just the way anybody else could play - and outcome of that game is according to this article proven theory of this guy denies dark matter and dark energy theory. And that's all, we could prove bad logic here without…

"Proven theory" isn't a thing, Milgrom is a scientist, he should be well aware of that. Using truth conditional logic here just doesn't make sense.

Re: A Physicist Who Denies Dark Matter

#82
post #72

Earlier quoted context omitted.

"there are no politics involved in this kind of research" While it might not be true in this case, you couldn't be further from the truth. there is an EXTREME amount of politics. people's careers are based on entire assumptions, thesis', papers, and work could be all for not if based on false assumptions.

Yeah there's a huge amount of politics in research IN GENERAL, but not so much in physics. Like there are no big questions covered up because they're inconvenient or anything.

the big bang theory was dismissed for decades. Even Einstein said to someone suggesting it that his physics was "abominable".

Re: A Physicist Who Denies Dark Matter

#83
A.Meessen suggest a simpler explanation. Dark matter is made of electrically neutral elementary particles subject to scattering and a pressure. These particles may combine and dissociate which accounts for drak energy and the cosmological constant. The properties of all elementary particles (except mass) are predicted by his space time quantization (STQ) theory. It provides a blue print of all elementary particles. It predicts the neutral elementary particles that may constitute dark matter. There is no need to call back in question Newton's theory.

[1] "From Space-Time Quantization to Dark Matter" https://www.scirp.org/journal/PaperInformation.aspx?PaperID=...

[2] "Accelerated Expansion of Space, Dark Matter, Dark Energy and Big Bang Processes" https://www.scirp.org/journal/PaperInformation.aspx?PaperID=...

[3] "Astrophysics and Dark Matter Theory" https://www.scirp.org/journal/PaperInformation.aspx?PaperID=...

Re: A Physicist Who Denies Dark Matter

#84
post #76

Earlier quoted context omitted.

Forget dark matter, use the analogy from the article: afaik nobody has ever proven ether is not existing. I know nothing about dark matter, but I could play a zero-sum game based on this article content - just the way anybody else could play - and outcome of that game is according to this article proven theory of this guy denies dark matter and dark energy theory. And that's all, we could prove bad logic here without…

"Proven theory" isn't a thing, Milgrom is a scientist, he should be well aware of that. Using truth conditional logic here just doesn't make sense.

This subthread deals with the completely different issue, it's about bad logic. No matter how well Milgrom and/or his theory could be discredited, that doesn't change the fact we can dismiss something prior to fully understand it.

It doesn't matter if that - what we dismissed - shapeshifts into something completely different (or similar...) afterward, on the contrary, regarding resources spent it would be sad if not.

Re: A Physicist Who Denies Dark Matter

#85
post #75
post #53

Earlier quoted context omitted.

I am not certain about the mechanics of it, but one of the most prominent theories right now is that dark matter is actually primordial black holes 1 . 1. https://www.nasa.gov/feature/goddard/2016/nasa-scientist-sug...

Sorry, but I don't understand your argument. When asked 'how do you explain lensing without dark matter?', your answer is 'with this particular flavor of dark matter'?

Well we're seeing a bunch of stuff happening out there and calling it dark matter.

1. The big problem is not enough stuff. Galaxies don't have enough stuff in them to let gravity hold them together.

2. A second problem is that we have stuff out there that our instruments can't detect but seems to be putting out gravity and bending the light.

The orthodoxy of dark matter says 1 and 2 are connected. That dark matter is bending light and causing extra stuff in galaxies to allow them to form and keep them from flying apart.

This physicist says no, just gravity doesn't work quite the way we think it does, because the stars in galaxy are moving at a constant speed relative to their distance from the galaxies center - but if there were a whole bunch of extra stuff in there that we can't see creating extra gravity all over the place, it should mess with the speed and cause it to be different depending on what parts had more dark matter in it.

My parent was saying, how do you explain the invisible stuff putting out gravity and bending light, and suggested that it could not be explained by black holes. I was pointing out that one of the main explanations for it is black holes, but that still doesn't solve the first big problem of not enough stuff.

Re: A Physicist Who Denies Dark Matter

#86

Almost ever sentence in this comment is wrong.

And the second word of the only sentence in your comment is wrong. Please provide a constructive, substantive critique or don't comment at all.

The fact that someone with more expertise is warning that a discussion is going off the rails is a useful, constructive fact. Demanding that that person explain in detail why in order to contribute is a good way to make sure they don't bother.

Re: A Physicist Who Denies Dark Matter

#87
post #74
post #66

Earlier quoted context omitted.

Right it's like when people say, I don't believe in Creation, that stuff is just nonsense. And you say, so what's your alternative theory then? And they reply, well there was a "big bang" and everything just sort of appeared, for no reason. Really, that's the alternative explanation?

When you get down to the bedrock, there's very little difference between theistic and atheistic explanations for creation.

That's total nonsense.

Re: A Physicist Who Denies Dark Matter

#88
post #74
post #66

Earlier quoted context omitted.

Right it's like when people say, I don't believe in Creation, that stuff is just nonsense. And you say, so what's your alternative theory then? And they reply, well there was a "big bang" and everything just sort of appeared, for no reason. Really, that's the alternative explanation?

When you get down to the bedrock, there's very little difference between theistic and atheistic explanations for creation.

Absolutely. "Big bang" or "let there be light", what's the difference?

Re: A Physicist Who Denies Dark Matter

#89
post #87
post #74

Earlier quoted context omitted.

When you get down to the bedrock, there's very little difference between theistic and atheistic explanations for creation.

That's total nonsense.

A.) God waved his finger, and the universe sprang into existence.

B.) something happened, and the universe sprang into existence.

Re: A Physicist Who Denies Dark Matter

#90

How do you explaining gravitational lensing with no visible mass, without dark matter? In other words situations where we see twin images of a very distant galaxy because light curves around intervening mass, without sufficient mass observable to explain the deflection? I was under the impression that we could map dark matter localized to a precision that tended to rule out measurement error or a general divergence f…

In the scenario you're describing a black hole would qualify, however IIRC there are other aspects of dark matter that black holes can't explain.

Yes, black holes and other compact objects have pretty much been ruled out as candidates for dark matter. The issue is that they would produce gravitational microlensing signals which are not observed. In brief, when the black hole passes in front of a star, its gravitational field magnifies the light from the star in a characteristic way. By analyzing the shape of the light curve, you can figure out pretty much everything about the system like the masses and the distances. Systematic surveys for these microlensing events like OGLE have not observed black hole microlensing events at the rate that would be needed for black holes to constitute most of the dark matter out there. They do observe quite a few planetary microlensing events, though.
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