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2018-10-28 Science & Technology
Dark prediction: Dark star made of dark matter could lead to entire dark universe
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Posted by Fred 2018-10-28 00:00|| E-Mail|| Front Page|| [6470 views ]  Top

#1 Aether, the next chapter.
Posted by Procopius2k 2018-10-28 08:13||   2018-10-28 08:13|| Front Page Top

#2 Yep, P2k.

The computer models all have spit the bit on this.
I find it hilarious listening to the big brains "describe" reality when they can't account for 80% of stuff (they think).

For all of humanities needs Newton still suffices. After that I think we have to fall back on G*d.
Posted by AlanC 2018-10-28 08:47||   2018-10-28 08:47|| Front Page Top

#3 ...We know gravity. We understand gravity...

actually we don't, at least not completely

we don't have an adequate quantum field theory of gravitrons;

also we are not sure about the interaction of gravity and dark energy (since we don't know that much about dark energy)
Posted by lord garth 2018-10-28 11:38||   2018-10-28 11:38|| Front Page Top

#4 Yeah, its just me, but I see a lot of 'modern' physics engaged in something that seems a lot like another Ptolemaic explanation exercise trying to fit the math and observations with preconceived belief of the universe. They have 'faith' it will all work out.
Posted by Procopius2k 2018-10-28 13:04||   2018-10-28 13:04|| Front Page Top

#5 Physics: Stuff doing stuff with other stuff.
Posted by Deacon Blues 2018-10-28 13:44||   2018-10-28 13:44|| Front Page Top

#6 Actually, AlanC, the GPS system needs to use Einstein's General Relativity to work as accurately as it does.
For most stuff that's human-scale, Newton works OK.

Testing hypotheses has gotten harder and harder. It turns out to be pretty tough to make a black hole to use for testing. And getting close to the existing ones takes a while and is quite uncomfortable.

Even if you're not looking for effects at the extremes, just verifying that your brand new theory covers all the bases can take months or years of calculations.

But the problem w/ theorists working in CloudCucuLand is well known--even some theorists complain about it. http://backreaction.blogspot.com/
Posted by james 2018-10-28 14:39||   2018-10-28 14:39|| Front Page Top

#7 It's a pity for Physics that the line between opinion and theory has become so blurred.

I mean you could have separate but nearby universes (like a stack of paper would be analogous to a group of 2d universes) if gravity wasn't constrained to just our universe.

But this "theory" isn't testable, so it's just my fun opinion.
Posted by Bright Pebbles 2018-10-28 14:51||   2018-10-28 14:51|| Front Page Top

#8 Testing hypotheses has gotten harder and harder It turns out to be pretty tough to make a black hole to use for testing..

Democrats and Socialists (BIRM) are testing out new locales
Posted by Frank G 2018-10-28 14:52||   2018-10-28 14:52|| Front Page Top

#9 For all of humanities needs Newton still suffices. After that I think we have to fall back on G*d.

How do you know that dark matter isn't G*d?
Posted by Abu Uluque 2018-10-28 15:30||   2018-10-28 15:30|| Front Page Top

#10 How do you know that dark matter isn't G*d?

Dark Matter is too localized to this solar system.
It's found as near as Uranus.
Posted by Skidmark 2018-10-28 15:53||   2018-10-28 15:53|| Front Page Top

#11 Not if I wipe properly


*going to my room*
Posted by Frank G 2018-10-28 15:57||   2018-10-28 15:57|| Front Page Top

#12 A little over 100 years ago, scientist were faced with the problem of the precession of the perihelion
link about the precession of Mercury’s perihelion
of Mercury which Newton mechanics could not explain. "Dark matter" in the form of planet Vulcan [https://arstechnica.com/science/2015/11/the-messy-reality-of-science-revealed-by-the-long-hunt-for-a-missing-planet/] was introduced to preserve Newtonian gravity but the problem was finally resolved by Einstein's General Theory of Relativity (GR) which modified Newton's theory.
Now move to today. The angular velocity of galaxies cannot be explained by GR so once again "dark matter" is introduced to explain it. I know, gravitational lensing offers support for dark matter but that is not ironclad. My money is on new Quantum theories of gravity [https://www.quantamagazine.org/erik-verlindes-gravity-minus-dark-matter-20161129/]. They haven't nailed it yet but I think they eventually will.
Posted by Jolurong Sinatra9506 2018-10-28 15:57||   2018-10-28 15:57|| Front Page Top

#13 The Freeman Dyson anecdote in a cautionary article on taking models as reality(Wavefunction blog):
The problem, as Fermi pointed out, was that Dyson's premise was based on fitting a curve to some data using four parameters. But, quipped Fermi, you can get a better fit to the data if you add more parameters. Fermi quoted his friend, the great mathematician John von Neumann - "With four parameters you can fit an elephant to a curve; with five you can make him wiggle his trunk".
So far we have observations that don't match our theory... Dark matter, dark energy, magic fairy dust or Supernatural intervention --- take your pick.
Posted by magpie 2018-10-28 18:26||   2018-10-28 18:26|| Front Page Top

#14 magpie, is it worth mentioning the ultimate model myth of the current age...Climate Change aka global warming.

Modeling of all kinds is the driver of GIGO.
Posted by AlanC 2018-10-28 21:10||   2018-10-28 21:10|| Front Page Top

#15 Nobody talking 10,11,12 dimensional vibrating strings?
Posted by 3dc 2018-10-28 21:20||   2018-10-28 21:20|| Front Page Top

23:28 gorb
23:24 rjschwarz
23:18 rjschwarz
22:30 trailing wife
21:27 Procopius2k
21:26 Bman
21:24 Procopius2k
21:23 3dc
21:20 3dc
21:10 AlanC
20:27 Grunter
19:54 SteveS
19:54 Frank G
19:51 SteveS
19:41 Thing From Snowy Mountain
19:33 SteveS
19:33 Silentbrick
19:27 Silentbrick
18:55 magpie
18:26 magpie
18:05 AlanC
18:05 Skidmark
17:57 Thing From Snowy Mountain
17:55 Thing From Snowy Mountain
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