The end of spacetime

Abstract

We will highlight that despite there being various approaches to quantum gravity, there are universal approach-independent features of quantum gravity. The geometry of spacetime becomes an emergent structure, which emerges from some purely quantum gravitational degrees of freedom. We argue that these quantum gravitational degrees of freedom can be best understood using quantum information theory. Various approaches to quantum gravity seem to suggest that quantum gravity could be a third quantized theory, and such a theory would not be defined in spacetime, but rather in an abstract configuration space of fields. This supports the view that spacetime geometry is not fundamental, thus effectively ending the spacetime description of nature.

arXiv commentEssay received an honorable mention in the Gravity Research Foundation Essay Competition 2023, 10 pages

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Cited by in corpus (4)

• Implications of Tarski's Undefinability Theorem on the Theory of Everything
• Consequences of Godel Theorems on Third Quantized Theories Like String Field Theory and Group Field Theory
• Information Theoretical Approach to Detecting Quantum Gravitational Corrections
• Can quantum gravity be both consistent and complete?