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Updated: Aug 5, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Anomaly in Canonical Semiclassical Gravity
1University of New Brunswick, Department of Mathematics and Statistics, Fredericton, New Brunswick, Canada.
Physical Review Letters
|July 31, 2026
Summary
The standard semiclassical Einstein equation formulation is inconsistent. Replacing matter terms with quantum expectation values leads to a non-closure of the constraint algebra, indicating a fundamental problem.
Area of Science:
- * Theoretical physics
- * Quantum gravity
- * General relativity
Background:
- * The semiclassical Einstein equation is a theoretical framework attempting to unify general relativity and quantum mechanics.
- * It involves replacing classical matter terms with quantum expectation values.
Purpose of the Study:
- * To analyze the consistency of the canonical formulation of the semiclassical Einstein equation.
- * To investigate the implications of using quantum expectation values for matter terms.
Main Methods:
- * Examination of the canonical formulation of the semiclassical Einstein equation.
- * Analysis of the constraint algebra resulting from the formulation.
Main Results:
- * The canonical formulation of the semiclassical Einstein equation is shown to be inconsistent.
- * This inconsistency arises from the non-closure of the resulting constraint algebra.
Conclusions:
- * The canonical formulation of the semiclassical Einstein equation, as currently defined, is not mathematically sound.
- * Further theoretical development is required to reconcile general relativity and quantum mechanics in this framework.
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