Non-time-orientable Lorentzian cobordism allows for pair creation
It is shown that if time-orientability is sacrificed, then, in any spacetime of odd dimension, two cobordant manifolds are also related by a Lorentzian cobordism. Thus, pair creation of Kaluza-Klein monopoles would be allowed in such a framework. The even-dimensional case is also examined.
scientific article; zbMATH DE number 3971691
scientific article