caa a22 4500 463196856 CHVBK 20180406164925.0 cr unu---uuuuu 170326e20070401xx s 000 0 eng 10.1007/s10773-006-9243-8 doi (NATIONALLICENCE)springer-10.1007/s10773-006-9243-8 Etesi Gábor Department of Geometry, Mathematical Institute, Budapest University of Technology and Economics, H ép., Egry József u. 1., H-1111, Budapest, Hungary aut Homotopic Classification of Yang-Mills Vacua Taking into Account Causality [Elektronische Daten] [Gábor Etesi] Existence of θ-vacuum states in Yang-Mills theories defined over asymptotically flat space-times examined taking into account not only the topology but the complicated causal structure of these space-times, too. By a result of Galloway apparently causality makes all vacuum states, seen by a distant observer, homotopically equivalent making the introduction of θ-terms unnecessary. But a more careful analysis shows that certain twisted classical vacuum states survive even in this case eventually leading to the conclusion that the concept of "θ-vacua” is meaningful in the case of general Yang-Mills theories. We give a classification of these vacuum states based on Isham's results showing that the Yang-Mills vacuum has the same complexity as in the flat Minkowskian case hence the general CP-problem is not more complicated than the well-known flat one. We also construct the θ vacua rigorously via geometric quantization. Springer Science+Business Media, LLC, 2006 θ-vacua nationallicence asymptotical flatness nationallicence causality nationallicence topological censorship nationallicence International Journal of Theoretical Physics Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 46/4(2007-04-01), 832-847 0020-7748 46:4<832 2007 46 10773 https://doi.org/10.1007/s10773-006-9243-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10773-006-9243-8 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Etesi Gábor Department of Geometry, Mathematical Institute, Budapest University of Technology and Economics, H ép., Egry József u. 1., H-1111, Budapest, Hungary aut NATIONALLICENCE 773 0- International Journal of Theoretical Physics Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 46/4(2007-04-01), 832-847 0020-7748 46:4<832 2007 46 10773 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer