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  Why are there no global continuous internal symmetries in quantum gravity?

+ 5 like - 0 dislike

I've heard it said that global continuous internal symmetries must be broken in any reasonable theory of quantum gravity. What's the precise version of this statement, and the reasoning behind it? (I know how to show this is true in string theory, but apparently there are more general arguments.)

asked May 20, 2014 in Theoretical Physics by photino (25 points) [ revision history ]
edited May 21, 2014 by photino

This is our first duplicate. How do we close as duplicate?

@RonMaimon It's not the first duplicate actually. Anyway, one can mark as duplicate by clicking "close" and checking the "this is a duplicate" option. Not sure, if there is the necessity for a formal vote to close.

I would generally vote to close in case of duplicates too ...

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