Embracing the glitches in gravity could give us a unified theory of reality — SkimNews
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- Jonathan Oppenheim, a physicist at University College London, wagered Carlo Rovelli and Geoff Penington at 5000-to-1 odds in 2023 that gravity is not governed by quantum theory — Rovelli and Penington would owe him £1,000 if proved correct; he would owe them 20p if not.
- Oppenheim's post-quantum gravity model keeps space-time continuous and indivisible rather than pixelating it at tiny scales, contrasting with string theory's curled-up extra dimensions and loop quantum gravity's geometric "grains."
- In a July paper with Zachary Weller-Davies at the Perimeter Institute in Canada, Oppenheim showed that key space-time symmetries from general relativity also hold within the post-quantum framework.
- The theory's central trade-off: it requires small random fluctuations in space-time coordinates, meaning the ticks of a clock would wobble slightly rather than come at equal intervals on tiny scales — an idea Oppenheim himself calls uncomfortable.
- Those same fluctuations cause the Born rule — a foundational quantum probability formula whose origin has eluded physicists for a century — to emerge naturally from the model without being assumed.
- Oppenheim's May work shows the model reproduces some gravitational effects currently attributed to dark matter, which observations indicate outweighs visible matter in the cosmos by roughly five to one.
- Critics remain unmoved: Ivette Fuentes at the University of Southampton says the randomness has no known physical source, while Rovelli argues the model violates both quantum mechanics and general relativity.
Why it matters: Oppenheim's framework sidesteps the untested extra dimensions of string theory and the discrete space-time of loop quantum gravity by preserving Einstein's picture of smooth, continuous space-time — but only at the cost of making time itself slightly random on small scales, and only if physicists accept a randomness whose physical origin remains unknown.
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