Old and New Questions in Physics, Cosmology, Philosophy, and Theoretical Biology pp 87-107 | Cite as

# CPT Invariance as Basic for Interpreting Quantum Mechanics

## Summary

This paper is an expanded version of one recently published in Foundations of Physics and is a continuation of previous works devoted to the EPR correlation.

The leading idea remains that the EPR correlation (either in its well-known form of nonseparability of future measurements, or in its less known time-reversed form of nonseparability of past preparations) displays the intrinsic time symmetry existing in almost all physical theories at the elementary level. But, as explicit Lorentz invariance has been an essential requirement in both the formalization and the conceptualization of my papers, the noninvariant concept of T symmetry has to yield in favor of the invariant concept of PT symmetry, or even (as C symmetry is not universally valid) to that of CPT invariance.

A distinction is then drawn between “macro” special relativity, defined by invariance under the orthochronous Lorentz group and submission to the retarded causality concept, and “lmicro” special relativity, defined by invariance under the full Lorentz group and including CPT symmetry. The CPT theorem clearly implies that “micro special relativity” is relativity theory at the quantal level. It is thus of fundamental significance not only in the search of interaction Lagrangians etc., but aJso in the basic interpretation of quantum mechanics, including the understanding ot the EPR correlation.

While the experimental existence of the EPR correlations is manifestly incompatible with macro relativity, it is fully consistent with micro relativity. It goes without saying that going from a retarded concept of causality to one that is CPT invariant has very radical consequences, which are briefly discussed.

## Keywords

Quantum Mechanic Relativistic Quantum Mechanic Feynman Propagator Time Symmetry Wave Collapse## Preview

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## References and Notes

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