Space curvature
5 Sep 2009 13:10:32 UTC
Topic 194524
(moderation:
The Arecibo radio telescope, together with other telescopes connected in a VLBA network, has repeated the observations made in 1919 at Principe Island which were the first observational evidence of general relativity. See here:
Arecibo
Tullio
Space curvature
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I love it when new (more accurate) measurements of such fundamental constants are made.. for instance, it would be amazing if we could redefine the kilogram in terms of the cosmological constants, or even come up with a new unit based on a metric multiple of them, instead of some arbitrary number. (using a metric base number system is pretty arbitrary, but that would be hard to change.. and besides binary, which would be impractical to use, using any other powers of two would also be arbitrary) As it is, our measurements of the gravitational constant aren't precise enough, and so other avenues are being investigated - such as engineering the roundest possible globe we can, then measuring the amount of atoms contained in it. This seems like a very indirect and messy way of doing things, but with gravity being as weak as it is..
Many attempts have been done
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Many attempts have been done to reconcile general relativity and quantum mechanics. Here is the latest I could find:
Gravitation
None has the beauty of Einstein's theory and the subtlety of quantum mechanics, which perhaps we have not yet mastered. God is subtle, but not malicious, said Einstein.
Tullio
Oh my, much work has gone
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Oh my, much work has gone into determing a worable theory of Quantum Gravity which reconciles general relativity and quantum mechanics. The jury is still out however. I like several recent attempts such as MOG by John Moffat:
http://astore.amazon.com/amuletdevelopmco/detail/0061170887
and there is also a great book on Loop Quantum Gravity:
http://astore.amazon.com/amuletdevelopmco/detail/0465078362
Of course there are plent of crackpot theories which you must be wary about.
Here is another, coming from
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Here is another, coming from AEI Potsdam:
Vanquishing infinity
Tullio