As some of you may know I really like having a google homepage so that I can have feeds to important websites like news, etc... On site I have feeds coming in from is

arxiv.org. I check to see what the new preprints are each day. These ones were pretty cool:(The first lead me to the rest)

- Instantons and Emergent Geometry
- Emergent Spacetime.
- Gauge/Gravity Duality

Weinberg and Witten showed that the graviton, a spin 2 particle, cannot be the product of two spin one particles. However, there are two assumptions they make with these authors don't. First is the assumption that gravitons exist in the same spacetime as other particles. If gravitons exist on a higher dimension that the other particles like in a brane world scenario their proof is invalid.

Second, they assume spacetime is commutative, ie [x,y]=0. If this turns out to be not correct then it is possible for a spin to graviton to emerge from two spin one E&M particles. I thought this was a cool result. Only time will tell.

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