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Member Since: 4/2008Last Seen: 11/24/2009

Refined Hubble Constant Narrows Possible Explanations for Dark Energy

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Whatever dark energy is, explanations for it have less wiggle room following a Hubble Space Telescope observation that has refined the measurement of the universe's present expansion rate to a precision where the error is smaller than five percent.



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{"commentId":6930659,"authorDomain":"jcatom"}

Their result is consistent with the simplest interpretation of dark energy: that it is mathematically equivalent to Albert Einstein's hypothesized cosmological constant, introduced a century ago to push on the fabric of space and prevent the universe from collapsing under the pull of gravity. (Einstein, however, removed the constant once the expansion of the universe was discovered by Edwin Hubble.)

"If you put in a box all the ways that dark energy might differ from the cosmological constant, that box would now be three times smaller," says Riess.

{"commentId":6930659,"threadId":"572814","contentId":"2786839","authorDomain":"jcatom"}
  • 6 votes
Reply#1 - Thu May 7, 2009 10:26 AM EDT
{"commentId":6931490,"authorDomain":"EvilTriplet"}
Evil TripletDeleted
{"commentId":6933980,"authorDomain":"jcimino-1"}

nice to learn new things

{"commentId":6933980,"threadId":"572814","contentId":"2786839","authorDomain":"jcimino-1"}
  • 1 vote
Reply#3 - Thu May 7, 2009 12:25 PM EDT
{"commentId":6935767,"authorDomain":"JoulesBeef"}

very cool.
yeah that darn constant... Einsteins biggest embarrassment and then it turns out.. his fudging the numbers might have been the correct thing to do.just not for his reasons.
But it is hard to overcome preconceived misconceptions.
it's a struggle for all science and really you are more susceptible to it the longer you stay in a particular field.

{"commentId":6935767,"threadId":"572814","contentId":"2786839","authorDomain":"JoulesBeef"}
  • 1 vote
Reply#4 - Thu May 7, 2009 1:15 PM EDT
{"commentId":6951962,"authorDomain":"ceosvcs"}

Perhaps the new light transmitter can help to increase the space in the dark box.....:)

{"commentId":6951962,"threadId":"572814","contentId":"2786839","authorDomain":"ceosvcs"}
  • 2 votes
Reply#5 - Fri May 8, 2009 7:42 AM EDT
{"commentId":7024592,"authorDomain":"bobnelsonfrance"}

I love the way astrophysics keeps crossing paths with particle physics...

{"commentId":7024592,"threadId":"572814","contentId":"2786839","authorDomain":"bobnelsonfrance"}
  • 2 votes
Reply#6 - Tue May 12, 2009 2:28 AM EDT
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