“If the weak gravity conjecture is right, loop quantum gravity is definitely wrong,” said Nima Arkani-Hamed, a professor at the Institute for Advanced Study who co-discovered the weak gravity conjecture.(adsbygoogle = window.adsbygoogle || []).push({});

source https://www.quantamagazine.org/where-gravity-is-weak-and-naked-singularities-are-verboten-20170620/

which also goes into detail weak gravity conjecture, which states that gravity must always be the weakest force in any universe.

I was of the understanding in certain braneworld scenarios, string theory "predicts" that gravity is the same strength as the other forces, including electromagnetism and strong force, but gravity - gravitons, are closed loops and its strength can be "diluted" by traveling to other higher dimensional branes, whereas electromagnetism and strong force consists of open ended strings suck on our 3-brane

so string theory "predicts" gravity is the same strength as the other forces, but is diluted as it is the only force consisting of closed strings, but string theory also "predicts" weak gravity conjecture that gravity must always be weaker than the other forces.

and this somehow disproves loop quantum gravity

can anyone elaborate?

why in string theory can't there be a universe whereby gravity and the other forces have the same strength, and other where gravity is the stronger force, and any combination in between

why does Nima Arkani-Hamed say weak gravity conjecture if true disproves loop quantum gravity when string theory predicts that in some universes gravity is the same strength as the other forces, but in others, it is weaker?

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# I Weak gravity conjecture and strings vs loops

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