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> The Planck length has no physical significance > There is no evidence to suggest that space is discrete at that scale

Bekenstein bound and "planckian discreteness".

Reality is most likely not composed of a regular tesselation of simple geometric shapes such as a cartesian voxel grid as that would introduce massive anisotropy. But, there is still theoretic evidence suggesting that spacetime is indeed discrete at the lowest level.

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Interesting stuff, and thanks - I didn't know about the Bekenstein Bound. I was referring to empirical evidence, though. AFAICS these are theoretical musings that, while they have some validity as far as they apply to the predictions of existing established theories, have to be considered entirely speculative in the quantum gravity regime where we don't have an accepted theory to base such reasoning on.

> empirical evidence

That is going to be a though one, at least direct measurements are pretty much ruled out if you consider that the plank length is about a quadrillion (yes, really 10^15) times smaller than the classical electron radius.

So, we will have to settle for indirect evidence and theoretical results.

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