I have been reading that the quantity called "Weyl curvature" can exist independently of any matter, or energy, in the universe?(adsbygoogle = window.adsbygoogle || []).push({});

This seems to contradict Heisenberg uncertainty which says there can be no 100% vacuum, because uncertainty in position and uncertainty in momentum must be greater than zero:

DxDp >= [Planck's constant]/[2*pi]

Mach's principle seems to say that the distribution of matter-energy determines the geometry of space-time, and if there is no matter-energy then there is no geometry.

The Weyl tensor vanishes for a constant curvature if there are no

tidal forces. So it appears that a Weyl curvature, which is described

as 1/2 of the Riemann curvature tensor[where it is split into two

parts, the Ricci tensor and the Weyl tensor] is dependent on

matter-energy -"existing" in the universe also?

Thanks for the help.

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# Weyl Curvature, Mach's Principle, and Heisenberg Uncertainty?

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