“One of the evident facts about the world is the stability of empty space-time. In classical general relativity we can explain this as a consequence of the positive energy theorem… the positive energy theorem must extend in some suitable form to any viable quantum theory of gravity.”
"Positive energy in quantum gravity" arXiv (Jun 10, 2014)
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Lee Smolin 52
American cosmologist 1955Related quotes
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[Why Is Gravity So Elusive? Frank Wilczek, Erik Verlinde, Laura Mersini-Houghton, 4 December 2017, YouTube, https://www.youtube.com/watch?v=7lui9qZ6cDs] 11:20 of 40:44