dorsal/arxiv
View SchemaTwin paradox and space topology
| Authors | Jean-Philippe Uzan, Jean-Pierre Luminet, Roland Lehoucq, Patrick Peter |
|---|---|
| Categories | |
| ArXiv ID | physics/0006039 |
| URL | https://arxiv.org/abs/physics/0006039 |
| DOI | 10.1088/0143-0807/23/3/306 |
| Journal | Eur.J.Phys.23:277,2002 |
Abstract
If space is compact, then a traveller twin can leave Earth, travel back home without changing direction and find her sedentary twin older than herself. We show that the asymmetry between their spacetime trajectories lies in a topological invariant of their spatial geodesics, namely the homotopy class. This illustrates how the spacetime symmetry invariance group, although valid {\it locally}, is broken down {\it globally} as soon as some points of space are identified. As a consequence, any non--trivial space topology defines preferred inertial frames along which the proper time is longer than along any other one.
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"abstract": "If space is compact, then a traveller twin can leave Earth, travel back home\nwithout changing direction and find her sedentary twin older than herself. We\nshow that the asymmetry between their spacetime trajectories lies in a\ntopological invariant of their spatial geodesics, namely the homotopy class.\nThis illustrates how the spacetime symmetry invariance group, although valid\n{\\it locally}, is broken down {\\it globally} as soon as some points of space\nare identified. As a consequence, any non--trivial space topology defines\npreferred inertial frames along which the proper time is longer than along any\nother one.",
"arxiv_id": "physics/0006039",
"authors": [
"Jean-Philippe Uzan",
"Jean-Pierre Luminet",
"Roland Lehoucq",
"Patrick Peter"
],
"categories": [
"physics.class-ph",
"physics.gen-ph"
],
"doi": "10.1088/0143-0807/23/3/306",
"journal_ref": "Eur.J.Phys.23:277,2002",
"title": "Twin paradox and space topology",
"url": "https://arxiv.org/abs/physics/0006039"
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