Dark Energy?

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Message 1313192 - Posted: 9 Dec 2012, 18:33:48 UTC

One for deep thought:


Einstein almost tagged dark energy in the early 1920s

It’s of historical interest only, at this point, but an analysis of an exchange between Albert Einstein and Erwin Schrödinger seems to show how close Einstein came to predicting the dark energy problem.

In this paper, ... much of it in the layman-impenetrable maths of relativity.

... Einstein added a term to maintain the state of the universe (and as we know, when Hubble demonstrated the expansion of the universe, Einstein happily wrote the constant off as his biggest mistake)...

... [Dark Energy] however, he finds deeply problematic: “one not only has to start out from the hypothesis of the existence of a nonobservable negative density in interstellar spaces but also has to postulate a hypothetical law about the space-time distribution of this mass density. The course taken by Herr Schrödinger does not appear possible to me because it leads too deeply into the thicket of hypotheses.” ...



I share Einstein's unease but certainly not from any capability of his depth of understanding! My suspicions are raised by the physics appearing to become more complex rather than gaining a greater wider view and simplicity. That suggests that there is some other effect at play that we are so far unaware of...

Hence, is the physics trying to describe multiple-facet observations of an as yet obscure source effect?


Keep searchin',
Martin


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Message 1313774 - Posted: 11 Dec 2012, 0:00:59 UTC - in response to Message 1313486.  
Last modified: 11 Dec 2012, 0:04:16 UTC

They have found the Higgs. The particle you are referring to is called a tachyon.

I'm with you; I think more time should be spent ruling out things like other physics altering the frequency of light giving perhaps a false doppler red shift.

Also, I guess that Einstein abandoned his early view of a steady-state universe by this admission.
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Message 1330989 - Posted: 25 Jan 2013, 1:11:19 UTC - in response to Message 1313774.  


NASA Officially Joins ESA's 'Dark Universe' Mission


PASADENA, Calif. -- NASA has joined the European Space Agency's (ESA's) Euclid mission, a space telescope designed to investigate the cosmological mysteries of dark matter and dark energy.

Euclid will launch in 2020 and spend six years mapping the locations and measuring the shapes of as many as 2 billion galaxies spread over more than one-third of the sky. It will study the evolution of our universe, and the dark matter and dark energy that influence its evolution in ways that still are poorly understood.


2020 is a long time to wait.
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Message 1331067 - Posted: 25 Jan 2013, 6:40:30 UTC

This reminds me of my college days. I was stumped on a calculas problem and finally in desperation added an X to my answer. When the professor asked what the X was for I said it was the symbol for the number that when multiplied by the rest of my solution would yield the correct answer. He wasn't amused.
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Message 1331165 - Posted: 25 Jan 2013, 15:53:11 UTC

Adding "x", that sounds a good engineering solution to me...
Bob Smith
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Somewhere in the (un)known Universe?
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Message 1331209 - Posted: 25 Jan 2013, 17:44:16 UTC

A possible alternative explanation for dark energy, and dark matter-- quantum gravity: http://www.newscientist.com/article/mg21729014.500-dwarf-planet-eris-may-reveal-quantum-gravity.html
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Message 1339483 - Posted: 19 Feb 2013, 23:20:40 UTC - in response to Message 1331209.  

This is going to be exciting!


ISS Dark Matter Experiment Poised To Yield Big News, Particle Physicist Says


BOSTON — Big news in the search for dark matter may be coming in about two weeks, the leader of a space-based particle physics experiment said today (Feb. 17) here at the annual meeting of the American Association for the Advancement of Science.

That's when the first paper of results from the Alpha Magnetic Spectrometer, a particle collector mounted on the outside of the International Space Station, will be submitted to a scientific journal, said MIT physicist Samuel Ting, AMS principle investigator.

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Message 1339491 - Posted: 20 Feb 2013, 0:34:18 UTC - in response to Message 1313192.  

ML,

I don't think that dark energy is needed to explain the expansion of the Universe. All that is needed is the Big Bang. The apparent fact that the rate of expansion is ostensibly increasing calls for some other source of energy arising out of the vacuum or some other form of attraction.

By rights the expansion should be slowing down now as gravity takes over from the big bang and the inflation expansion. But you know the far away galaxies are showing us what happened billions of years ago when the expansion would have been very rapid.

so i ask;

How sure are we that the expansion rate of the universe is increasing ? Also could there be another universe attracting us ??
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Message 1353029 - Posted: 3 Apr 2013, 23:49:12 UTC - in response to Message 1339491.  

They found first signs of dark matter, a mysterious component of the Universe.



Alpha Magnetic Spectrometer zeroes in on dark matter
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Message 1353051 - Posted: 4 Apr 2013, 0:34:57 UTC

Maybe this dark energy and dark matter exist in a dimension that Sci Fi writers have dubbed sub-space.
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Message 1353128 - Posted: 4 Apr 2013, 5:56:35 UTC - in response to Message 1353051.  

I had no idea CERN, was involved with the Alpha Magnetic Spectrometer project.

There is more to this page.


First Result from the Alpha Magnetic Spectrometer on the International Space Station:
Precision Measurement of the Positron Fraction in Primary Cosmic Rays of 0.5–350 GeV A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on 6.8×106 positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to ∼250  GeV, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.

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Message 1354004 - Posted: 6 Apr 2013, 6:44:19 UTC - in response to Message 1353128.  

I believe that the AMS-2 main control room is at CERN. Another is in Taiwan.
Tullio
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Message 1354229 - Posted: 7 Apr 2013, 0:16:30 UTC

There is no dark energy! It doesn't exist!
There is no dark matter! It doesn't exist!
There are no black holes! They don't exist!
And there was no big bang! It never happened!

Guys i told you this before and ye still insist on trusting and believing the chain of lies being fed to you through scientific journals and science news websites.

Get with the program guys. Johnney Guinness speaks the Truth!

John.
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Message 1354253 - Posted: 7 Apr 2013, 4:04:11 UTC

One more proof of Einstein GR:
Kepler confirms Einstein
Tullio
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Message 1354295 - Posted: 7 Apr 2013, 9:06:56 UTC - in response to Message 1354294.  

Dark matter was called "missing mass" by astronomer Fritz Zwicki in 1935, basing only on Newtonian mechanics. Dark energy is a recent addition because it seems that the expansion of the Universe, as described by the Hubble parameter, instead of slowing down or remaining constant is accelerating.
Tullio
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Message 1354385 - Posted: 7 Apr 2013, 12:19:15 UTC

Hi guys i'm having a bit of trouble understanding some of the new assumtions like the expantion of the universe wouldn't it mean that the universe slowed down and now they are saying it is speeding up ?. Why did it slow down ? If it's got something to do with the Higgs field then does that mean the Higgs field was there before the big bang ?. And could dark energy be one off the Higgs particles ?

I'll leave some other questions I have till a later time there to do with the newest theory about the universe being a hologram !!

I'm having trouble understanding the expansion itself and the universal constant , to expand that quick would suggest it is possible to travel faster than light ?? so maybe that part is not right ?

Wasn't the expansion put there only to make the theory work ? which is why i'm thinking maybe it is wrong ?

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Message 1354387 - Posted: 7 Apr 2013, 12:33:10 UTC - in response to Message 1354385.  

Thought I better put in that i'm talking about the first few seconds to aprox 300,000 yrs while things where still cooling down i'm not talking about the expansion after this time till presant
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Message 1354394 - Posted: 7 Apr 2013, 12:50:52 UTC - in response to Message 1354387.  
Last modified: 7 Apr 2013, 12:51:31 UTC

Thought I better put in that i'm talking about the first few seconds to aprox 300,000 yrs while things where still cooling down i'm not talking about the expansion after this time till presant

I am not prepared to talk about inflation. The theory is by an astrophysicist called David Guth who is now at MIT. You had better ask him. About the Universe being a hologram, here is a very interesting "Nature" article.
Fire in the hole!
Tullio
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Message 1354405 - Posted: 7 Apr 2013, 14:14:28 UTC - in response to Message 1354394.  

Whew I couldn't sleep till I relised I got the post wrong and I was talking about inflation and not expantion .

I'm glad you figured out that I was talking about inflation.

So I figure your like me have some big prob's with it and the holographic universe .

It's one thing to say the universe is expanding because of the Doppler red shift but to say it's speeding up using the same theory I can't understand that one
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Message 1354406 - Posted: 7 Apr 2013, 14:41:31 UTC

Thanks Tullo that link answered what would have been tomorrows question and information being lost in black holes .

So what do you think Dark energy and matter are ? a Higgs particle or anti Higgs field ? or something that yet needs a name
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Message boards : Science (non-SETI) : Dark Energy?


 
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