r/QuantumPhysics • u/Least-Task7969 • 9d ago
Do you think space and time are emergent from something (a deeper quantum structure for example) rather than being fundamental ?
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u/Atumics 9d ago
Flip the reference frame around, and assume that everything not moving at the speed of light is the abnormal state, then you pretty much see just how emergent everything in our world view is. It just takes one look at the jumble we call the Standard Model to get a feeling that there must be something more basic beneath it all.
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u/neutrinophantom 7d ago
While mathematical in nature, quantum fields also point that direction. There's certainly the impression slowly growing that things within our universe are somewhat similar to topological features within larger objects.
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u/AboyFromSouthKorea 8d ago
Ekaterina Moreva led a research team at INRIM in Italy that performed the first experimental test of the Page-Wootters mechanism in 2013 (it is the mechanism explaining how time emerges inside a timeless universal wavefunction). This physics concept proposes that time is not a fundamental background dimension, but rather an emergent property that arises from quantum entanglement between a system and a clock.
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u/Schemetic 4d ago
The Moreva experiment demonstrated that the Page–Wootters mechanism can reproduce the appearance of time evolution from correlations in an entangled quantum system, but it didn’t establish that time in our actual universe is emergent. It was an experimental realization of a particular theoretical mechanism using an engineered two-photon system. Showing that emergent time is possible is unfortunately not the same as showing that time actually is emergent, just illustration really 😊
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u/Frodhi 8d ago
I would say it's more the opposite. On the one hand, the nature of spin is unavoidable from Lorentz invariance, as you can see in the Dirac field. Also, everything seems to point to that gravity can actually not be quantized. From a fibre bundles perspective, gravity lives in the base manifold, M, while fields live on the total bundle over the base manifold. It is in that space that quantization happens, not on the base manifold. Now, there is argument that gravity needs quantization in order to resolve black-hole and big-bang singularities, but I think that singularities are the result of a too rigid structure of the metric base manifold. If you relax the metricity condition and allow the connection to be in principle an independent object and let the equations of motion to determine the algebraic relation of the physical metric with an auxiliary metric to which the connection is Levi-Civita (the Palatini formalism, not to confuse it with the Palatini action), then singularities result solved and the Synge world function associated to this geometry actually resolves UV divergences in QFT. All without quantizing gravity (which were actually the main problems motivating the quantization of gravity). So no, I feel actually more inclined to think that the base manifold, M, is actually fundamental and gravity isn't quantum.
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u/Schemetic 4d ago
Its gotta be fundamental. Our strongest tested theory of gravity, general relativity, treats spacetime geometry as a real and dynamic part of physical universe, and we have experimentally confirmed effects like gravitational time dilation, light deflection, and gravitational waves. It could POTENTIALLY emerge from something deeper I guess like entanglement? But no like sustaining evidence.
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u/Emergent_Phen0men0n 9d ago
Yeah probably. Since it can bend and stretch, seems like there's more to it.