Wave Function Collapse Triggering Spacetime Dynamics in Semiclassical Gravity

TL;DR

This paper introduces a semiclassical model where wave function collapse causes spacetime changes, aiming to unify quantum mechanics and gravity without quantizing spacetime, and suggests experimental tests for this approach.

Contribution

It proposes a novel semiclassical mechanism linking wave function collapse to spacetime dynamics, avoiding superposed spacetimes and providing testable predictions.

Findings

Collapse induces spacetime metric changes via Einstein's equations

Numerical simulations show gravitational perturbations from superposition collapse

Experimental designs proposed for detecting gravitational effects of collapse

Abstract

We propose a novel semiclassical mechanism to unify quantum mechanics and general relativity, where wave function collapse in a superposition state induces a rapid change in the energy-momentum tensor, triggering spacetime dynamics that propagate at the speed of light. Unlike models assuming superposed spacetimes, we posit that the superposition yields a single, continuous classical spacetime driven by the expectation value of the energy-momentum tensor. Upon collapse, the abrupt shift modifies the spacetime metric via Einstein's field equations, respecting causality. We explore this for a particle in a spatial superposition, propose detailed experimental designs with numerical simulations of gravitational perturbations, address potential theoretical challenges, and discuss implications for existing quantum-gravity theories. This framework offers a pathway to reconcile quantum and gravitational dynamics without quantizing spacetime, with testable signatures in future experiments.