Is dark matter real?

Chipper Q
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RE: RE: I happened to run

Message 38301 in response to message 38300

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Quote:
I happened to run across 'Modulated Quantum Neutron Fusion', and therein is a 'Comprehensive Unification Theory', ........... how it could be wrong. I look forward to hearing what everyone here thinks about it.

Crap on a stick, alas. He tried to get funding from the DoE, and they politely and rightly punted him over the fence. His 'papers' are reams of piffle/waffle .... please don't anyone give this guy any money :-)
Cheers, Mike


Thanks for taking the time to look that over, Mike. I didn't see an issue with solicitation of funds since he didn't appear to be asking for anything, and cited a patent pending. I feel stupid for not being able to recognize either piffle, or waffle, but this surely wouldn't be the first time I failed to see the difference between apple butter and you-know-what.

So there are no theories, still, that address where the mass of the fundamental particles comes from? It seemed quite plausible that light could trap a region of dark energy (or get trapped precessing around a region of higher energy density) to form a particle, or at least appear particle-like...

debugas
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RE: So there are no

Message 38302 in response to message 38301

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So there are no theories, still, that address where the mass of the fundamental particles comes from?


I am not a specialist, you know, but i always thought the mass (here i mean mass at rest) comes from oscilations of values in the information fields - the more the values move back and forth the harder it is to knock them out off the way (hence the inertia). To my mind quantity of motion (mv) is more fundamental than mass m or speed v
fundamental particals must have intrinsic pattern of fluctuation of values that characterize the given particle and the fluctuation of values gives certain quantity of motion which we then can project as some mass m moving at speed v

How do you distinguish two fundamental particles - they are clouds of some information values behaving in certain way specific for the given particle that distinguish it from any particle of other type.

Can anybody explain why the m/e (mass of electron) has the value it has ?
It must have something to do with quantity of charge motion within electron.
any theory with wave function corresponding to charge distribution ?
Could it be that to organize charge transmission the laws of nature require not just any but certain amount of motion to be involved into the operation ?

Mike Hewson
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RE: Thanks for taking the

Message 38303 in response to message 38301

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Thanks for taking the time to look that over, Mike. I didn't see an issue with solicitation of funds since he didn't appear to be asking for anything, and cited a patent pending. I feel stupid for not being able to recognize either piffle, or waffle, but this surely wouldn't be the first time I failed to see the difference between apple butter and you-know-what.


Don't kick yourself around! :-)

The guy does write well, it's just rubbish. As the DoE guy pointed out, the final state of his project has higher mass/energy than the initial! You have to put energy in to achieve that, not obtain energy from it. A modern day perpetual motion machine, yet another, with application for a patent etc.

Interestingly: Einstein in his work at the Swiss patent office in Berne, used the principle of conservation of energy to discount many applications. This he could confidently and fairly readily do, without needing to examine the detail of the proposed intervening mechanisms. Hence he had plenty of spare time to think of other things - like Relativity!

The other problem with 'MNQF' is that if true, with the consequences he has derived, then we wouldn't be around to discuss it. Everyday matter, and us with it, would not be stable. He proposes a low energy transition ( ie. at 'everday' energies ) at nuclear level, converting hydrogen to helium. This would leave life in the world somewhat bereft of helpful atoms.

A central problem with any new theory is not explaining or integrating with some specific phenomenon - it is staying consistent with a range of known phenomenon, and without invoking behaviour which is not contradicted by observations. Particle physics is awash with candidate theories that explain various results, but definitely imply new particles and findings that have certainly not been seen ( and should have easily been detected if present ).

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So there are no theories, still, that address where the mass of the fundamental particles comes from?


Yes, there is the Higgs Field with it's Higgs Bosons. Ambitious and upcoming accelerator experiments ( LHC ) hope to define this. But this ( in my view ) while giving a mechanism only de-references the question(s) another explanatory layer further back. This is pretty inevitable given the reductive approach of science methods.

Quote:
It seemed quite plausible that light could trap a region of dark energy (or get trapped precessing around a region of higher energy density) to form a particle, or at least appear particle-like...


Well done! There is indeed an interesting correlation here, in that the externally measurable black hole property types ( not the values of ) - mass, electric charge, angular momentum - are those of our fundamental particles!
Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter. Blaise Pascal

Ben Owen
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Folks, Dark matter is not

Folks,

Dark matter is not an arbitrary trick to make things work. When you look at the rotation curves of galaxies, they don't fit what you'd predict from the distribution of blue light. That is, if you assume that the mass is concentrated where the blue light is (which seems to work pretty well in other cases) and apply Newtonian gravity, you predict a rotation velocity profile significantly different from what is observed.

So, to simplify, you have two choices: Keep Newtonian gravity and assume that there is some extra mass you're not seeing in blue light, or assume that the blue light really shows you where the mass is and modify Newtonian gravity.

Most physicists vastly prefer the former, and it's not for arbitrary reasons. If you ditch Newtonian gravity you ditch relativity. Yes we are very attached to relativity, but not for silly sentimental reasons. The number one reason, as always in science, is: It works. It fits with what we know about a lot of other things, and it has been tested directly pretty well in various contexts itself.

There's another thing which typically gets left out of the various writeups. In physics and astronomy there is a history of situations like this where some new experiment or observation doesn't fit and you either have to throw out a well-established theory (if what you see is all that is there) or conclude that there is new stuff you aren't seeing (if you keep the theory). A classic example is the neutrino: Experiments with beta decay of atomic nuclei showed some missing energy and momentum. Either you drop the conservation laws, which screws up your understanding of how everything else in physics works, or you say there's another particle being produced which you aren't seeing because it's (i) very light, (ii) electrically neutral, and (iii) weakly interacting with everything. Fermi did the latter and called the presumed missing particle "neutrino" meaning little neutral one. Years later they figured out how to detect neutrinos directly, and now they're important tools in astronomy.

In other words: If you invoke MOND you make a mess of a lot of other theories and have to work very hard to explain why those theories have matched other experiments and observations so well in spite of being wrong. If you invoke dark matter you are just saying that we missed something when we were adding up all the stars, which is much easier to believe since things like that have happened before.

Hope this helps,

Ben

DanNeely
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Ben: that's the best

Ben: that's the best explanation I've seen on the subject so far. Do you mind if I borrow it for use elsewhere?

tullio
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Ben, you convinced me on dark

Ben, you convinced me on dark matter. Your reasoning follows Occam's Razor. But what about dark energy? Thanks for an answer.
Tullio

Dr. Bannaga Basheir Omer
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I Think scinece history is

I Think scinece history is yet to be understood well, and by many even among specialists, Scince history is a hot area which not only bring sequential order to discoveries or theories thus far put forth but examines the logics of science thinkings and connections between great minds in terms of thought processes and inquries attempted. The question brought in explains the predicament faced every day by scientific people, for lack of close follow up of how these theories are derived to explain phenomenon. Our perplexity are yet to be touched upon very handly.

Ben Owen
Ben Owen
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Dan, Feel

Dan,

Feel free.

Tullio,

There is plenty of evidence for dark energy too. Mike H mentioned the supernova observations. There are also observations of galaxy clusters, and of the cosmic microwave background. All of them point to the composition of the universe being about 30% matter (most of which is dark) and 70% something else. Aside from the amount of something else, the observations tell us that this stuff has negative pressure.

I guess they decided to call the something else "dark energy" since it's dark and the negative pressure makes it look like the quantum mechanical vacuum energy we've known about for the better part of a century. We don't know what the dark energy is, though people have tried and are trying various things. The obvious culprit is vacuum energy, but when you plug in the numbers they're off by 120 orders of magnitude so that's not it.

Mathematically it does resemble Einstein's cosmological constant, but that's just a coincidence. Einstein stuck that into his equations because he wanted a static universe. Nobody wanted dark energy; it's something that came out of the observations.

Strictly speaking, you could still make a theory without dark energy. If you say old supernovae are somehow different from new ones (chemistry of the stars?), hot gas in galaxy clusters is being stirred up by something else we haven't seen, something weird has messed up the microwave measurements, relativity is off, and/or a few other things. And if you say that all these things were off in ways that somehow conspired to make it consistently like 70% dark energy with a pressure/density ratio of about -1.

Once again, the simplest explanation for why the universe looks like it's 70% dark energy is that it really is 70% dark energy. If we can figure out what it is, we might be able to detect it directly, the way it eventually happened with neutrinos.

Hope this helps,

Ben

tullio
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Ben, thanks for your

Ben, thanks for your explanations, although they seem to convey a shocking picture of our ignorance. I have a degree in theoretical physics obtained in 1967 at Trieste University, near where Abdus Salam founded the International Center for Theoretical Physics and yet I must confess I know next to nothing about our Universe and probably I won't live long enough to kmow what dark matter and dark energy really are. Perhaps Newton was right when he compared himself to a boy playing with pebbles on the shore of the "great undiscovered ocean of truth".
Thanks again.
Tullio

gravywavy
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RE: ...To my mind quantity

Message 38310 in response to message 38302

Quote:
...To my mind quantity of motion (mv) is more fundamental than mass m or speed v
...

In relativity, many Newtonian vectors team up with a Newtonian scalar to make four-vectors, sometimes called Minowski vectors.

Most famously, position teams up with time to make a kind of 4-space postition 4-vector, with the three components of position as the spacelike components and time as the timelike component, (t, x, y, z)

Less well known, but equally important, is that energy teams up with momentum in the same way. So mc^2 is the timelike component of the 4-vector that has mv as its three spacelike components, (mc^2, mvx, mvy, mvz) -[where vx is v subscript x]

Confusingly, relativists use the word mass in two different ways, depending on where they learnt relativity.

Some of them use mass to mean the timelike component divided by c^2.

Others use mass to mean the modulus(*) of that 4-vector divided by c^2. As the modulus is the same for all observers, so the other lot would refer to this value as either the proper mass, rest mass, or the invariant mass.

As the proper mass is independent of the observer's motion, and both mv and mc^2 depend on which observer makes the measurement, I would say proper mass is the more fundamental property of an object.

hope that is food for further thought...
River~~

(*) Note, in relativity the modulus of (t, x, y, z) is sqrt(t^2 - x^2 - y^2 - z^2), ie there are minus signs where you'd expect plus signs. This is just one of the many ways Relativity re-writes ordinary vector geometry.

~~gravywavy

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