2002/02/28 by Mark J Hadley · 14 citations
Medicine · Physics and Astronomy · #Annihilation #Antiparticle #Biofield Effects and Biophysics #Causal sets #Classical mechanics #Event (particle physics) #Mathematical physics #Particle physics #Physics #Quantum Mechanics and Applications #Quantum field theory in curved spacetime #Quantum gravity #Quantum mechanics #Radioactive Decay and Measurement Techniques #Space time #Spacetime #Spacetime topology #Stationary spacetime #Theoretical physics #gr-qc #quant-ph
paper · pdf · doi:10.1088/0264-9381/19/17/308
published in Classical and Quantum Gravity 19(17), 4565-4571 (IOP Publishing) · 5 Pages plus 3 figures. More explanations added as requested by referees. Figures enhanced
arxiv created 2002/06/23 · openalex publication_date 2002/08/15 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Contrary to established beliefs, spacetime may not be time-orientable. By considering an experimental test of time-orientability it is shown that a failure of time-orientability of a spacetime region would be indistinguishable from a particle–antiparticle annihilation event.