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Comment: Re:what if... (Score 1) 234

by mbone (#49362193) Attached to: Dark Matter Is Even More of a Mystery Than Expected

There have been several theories built on that assumption, most prominently one called MOND (MOdified Newtonian Dynamics), but more recently one that builds on relativity rather than Newtonian gravity/dynamics.

But none of these theories (hypotheses?) have gained much acceptance from the physics community, as far as I know.

Yes, and one reason is that they find it hard to model these kinds of galaxy cluster observations in MOND / TeVeS without assuming there is also some dark matter or some other non-MOND effect involved. Now, that could be (and MOND proponents will point out that standard CMD also has its problems, e.g., with the core/cusp problem, and we don't throw out CDM every time such a problem is encountered), but it certainly takes some of the shine off of the theory.

Comment: Re:WIMPs (Score 1) 234

by mbone (#49362155) Attached to: Dark Matter Is Even More of a Mystery Than Expected

I don't have the article in the mail yet, but I'm guessing that's new. At the very least, Weakly Interacting is now Really Weakly Interacting.

Here you go.

From my perspective, it hardly changes a thing (it lowers the cross section / mass constraint a little, but not even an order of magnitude). But, then, I'm not a WIMP guy.

Comment: Re:WIMPs (Score 1) 234

by mbone (#49362143) Attached to: Dark Matter Is Even More of a Mystery Than Expected

Math proofs are meaningless without physical observations to back them up.

Fully agree. And, as it happens, General Relativity has a massive amount of physical observation backing it up, and no physical observations contradicting* it.

* If you believe in MOND / TeVeS, then the dark matter observations contradict GR. Let's just say that there is not yet consensus around that view.

Comment: Re:WIMPs (Score 1) 234

by mbone (#49361765) Attached to: Dark Matter Is Even More of a Mystery Than Expected

That the thing about dark matter... it has a perfectly reasonable explanation (WIMPs). It's not that weird of a "thing".

I dunno. Usually when a theory requires more and more unseen entities over time it's a sign that it's time to replace the theory. We know General Relativity is incomplete, both because it doesn't take into account quantum effects and because it has internal contradictions - specifically, it assumes a continuous spacetime geometry but predicts non-continuous points (black hole singularities).

That is not thought to be an internal contradiction of General Relativity, as, even though GR does have singularities, thanks to event horizons and cosmological censorship, there are no known cases where you can use these singularities to derive multiple different estimates of the same observational quantity (which is what having an inconsistent physical model means). I don't believe that there are any mathematical proofs of this, but I suspect you would have to come up with a counter-example if you wanted to convince people GR was self-contradictary.

Comment: Re:WIMPs (Score 1) 234

by mbone (#49361719) Attached to: Dark Matter Is Even More of a Mystery Than Expected

Dark energy is just the latest name for the Cosmological Constant

You know, I'm as happy as anyone else that physicists have been able to do so much with their models, but what kind of navel-gazing mathurbation is this?

Dark energy is an observed physical phenomenon.

The cosmological constant is a term in an equation. It's a very good equation, mind you, but a lot of very good equations have later turned out to be wrong or good for only a special class of phenomena. Equations can predict, but they don't prove anything. It's also worth noting that the cosmological constant was supposed to predict a force that would hold the universe together. Dark energy is a force that is tearing the universe apart. Someone clever pointed out that hey, that works if you just flip the sign of the cosmological constant but I'm not sure I'd call that a win.
 

This is physics. Everything is a term in an equation.

The cosmological constant is the only free parameter in Einstein's equations. The. Only. One. And, it fits exactly all of the available data. Unless and until that changes, there is no good reason to believe to believe that we do not live in a de Sitter space.

Comment: Re:WIMPs (Score 1) 234

by mbone (#49361693) Attached to: Dark Matter Is Even More of a Mystery Than Expected

That's exactly backwards.

The WIMP miracle is over; unless the LHC finds success with its Hail Mary pass, interest in WMPs will inevitably decline, and people will look (are looking) at other explanations for Dark Matter.

Dark Energy, on the other hand, is just a cosmological constant. Nothing mysterious (from a General Relativistic standpoint) about it at all.

Comment: Fucking Useless (Score 1) 262

by Khyber (#49350319) Attached to: Generate Memorizable Passphrases That Even the NSA Can't Guess

"7,776 English words"

So, less than 1/40th of the English Language.

What a short surface for a dictionary attack.

Slashdot needs to get some real people with REAL technical capability on-board. Timothy obviously can't figure out that HughPickens.com is a complete fucking idiot that can't determine whether or not the stories are worth a fuck for reporting (plus, the fag is shilling in his username alone.)

Comment: This will be used against blacks (Score 1) 882

by mbone (#49338675) Attached to: Gen Con Threatens To Leave Indianapolis Over Religious Freedom Bill

You can put money on two things

- this will be used to deny service to blacks (safe bet, as it already has been).

- that will not go over well, in a burn the place down sort of way.

And, at that point, it will probably be thrown out in court or amended out of existence by the legislature.

If you think the system is working, ask someone who's waiting for a prompt.

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