Emergent physics on Mach's principle and the rotating vacuum

TL;DR

This paper explores how Mach's principle relates to the rotation of the quantum vacuum and how high-energy effects could make vacuum rotation observable, using analogies from condensed matter physics.

Contribution

It demonstrates that the observability of vacuum rotation depends on Lorentz invariance at high energies, linking quantum gravity effects to Mach's principle through condensed matter analogies.

Findings

Low-energy observers cannot detect vacuum rotation.

High-energy observers can observe rotation due to Lorentz invariance violation.

Analogies with condensed matter systems illustrate the effects.

Abstract

Mach's principle applied to rotation can be correct if one takes into account the rotation of the quantum vacuum together with the Universe. Whether one can detect the rotation of the vacuum or not depends on its properties. If the vacuum is fully relativistic at all scales, Mach's principle should work and one cannot distinguish the rotation: in the rotating Universe+vacuum, the co-rotating bucket will have a flat surface (not concave). However, if there are "quantum gravity" effects which violate Lorentz invariance at high energy, then the rotation will become observable. This is demonstrated by analogy in condensed-matter systems, which consist of two subsystems: superfluid background (analog of vacuum) and "relativistic" excitations (analog of matter). For the low-energy (long-wavelength) observer the rotation of the vacuum is not observable. In the rotating frame, the "relativistic" quasiparticles feel the background as a Minkowski vacuum, i.e. they do not feel the rotation. Mach's idea of the relativity of rotational motion does indeed work for them. But rotation becomes observable by high-energy observers, who can see the quantum gravity effects.