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Title: Superluminal matter waves

Journal Article · · Physical Review Research

The Dirac equation has resided among the greatest successes of modern physics since its emergence as the first quantum mechanical theory fully compatible with special relativity. This compatibility ensures that the expectation value of the velocity is less than the vacuum speed of light. Here, we show that the Dirac equation admits free-particle solutions where the peak amplitude of the wave function can travel at any velocity, including those exceeding the vacuum speed of light, despite having a subluminal velocity expectation value. The solutions are constructed by superposing basis functions with correlations in momentum space. These arbitrary velocity wave functions feature a near-constant profile and may impact quantum mechanical processes that are sensitive to the local value of the probability density as opposed to expectation values.

Research Organization:
University of Rochester, NY (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES); Marie Skłodowska-Curie; USDOE National Nuclear Security Administration (NNSA)
Grant/Contract Number:
NA0004144; NA0004144
OSTI ID:
2475974
Journal Information:
Physical Review Research, Journal Name: Physical Review Research Journal Issue: 4 Vol. 6; ISSN 2643-1564
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

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