Quantum mechanics in fractional and other anomalous spacetimes

TL;DR

This paper develops a formulation of quantum mechanics in fractional and anomalous spacetimes, revealing how non-unitarity and modified measures affect quantum behavior while maintaining a correspondence with standard quantum theory.

Contribution

It introduces a quantum framework in fractional geometries, demonstrating the preservation of Heisenberg's principle and analyzing the effects of non-unitarity and topological terms.

Findings

Heisenberg's principle holds in fractional spacetimes.

Wave-functions minimizing uncertainty are identified.

Non-unitarity is encoded in initial and final state contributions.

Abstract

We formulate quantum mechanics in spacetimes with real-order fractional geometry and more general factorizable measures. In spacetimes where coordinates and momenta span the whole real line, Heisenberg's principle is proven and the wave-functions minimizing the uncertainty are found. In spite of the fact that ordinary time and spatial translations are broken and the dynamics is not unitary, the theory is in one-to-one correspondence with a unitary one, thus allowing us to employ standard tools of analysis. These features are illustrated in the examples of the free particle and the harmonic oscillator. While fractional (and the more general anomalous-spacetime) free models are formally indistinguishable from ordinary ones at the classical level, at the quantum level they differ both in the Hilbert space and for a topological term fixing the classical action in the path integral formulation. Thus, all non-unitarity in fractional quantum dynamics is encoded in a contribution depending only on the initial and final state.