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Nice paper: Constraints on possible "antigravity" of antimatter

A new preprint on arXiv does an excellent job of deriving strong constraints on the possible "antigravity" (gravitational repulsion) of antimatter, based on very precise experimental data and a minimum of theoretical assumptions. Karshenboim goes through several complex and detailed analyses to set tight limits on antigravity effects.

The argument I like best goes as follows: if antimatter feels a gravitational repulsion relative to matter, then "pure neutral" bodies, like positronium (bound states of e+ and e-) or photons (which are their own antiparticles) should feel no gravity at all. That trivially contradicts the gravitational deflection of light, and therefore can't be true.

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Nov 15, 2008. 8:18 PMalex-sharetskiy says:
If only i understood phisics more... i guess i'll have to wait till next year, when i'll have the class
Nov 15, 2008. 9:31 PMalex-sharetskiy says:
I don't really know about teachers..

I can't learn straight from the book, i have to have a teacher explain it in class, only then i can do it (any subject but English, PE, or electronics)

There is a government lab in town, LLNL i don't really know if that counts for anything, i think it might
Nov 15, 2008. 9:54 PMalex-sharetskiy says:
That's just the way i learn, i have to see each step separately

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