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Teleparallel gravity shares many qualitative features with general relativity, but differs from it in the following way: whereas in general relativity, gravitation is a manifestation of spacetime curvature, in teleparallel gravity, spacetime is (always) flat. Gravitational effects in this theory arise due to spacetime torsion. It is often claimed that teleparallel gravity is an equivalent reformulation of general relativity. In this paper we question that view. We argue that the theories are not equivalent, by the criterion of categorical equivalence or any stronger criterion, and that teleparallel gravity posits strictly more structure than general relativity.
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Newtonian Equivalence Principles
The equivalence principle has constituted one of the cornerstones of discussions in the foundations of spacetime theories over the past century. However, up to this point the principle has been considered overwhelmingly only within the context of relativistic physics. In this article, we demonstrate that the principle has much broader, super-theoretic significance: to do so, we present a unified framework for understanding the principle in its various guises, applicable to both relativistic and Newtonian contexts. We thereby deepen significantly our understanding of the role played by the equivalence principle in a broad class of spacetime theories.
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- Award ID(s):
- 1947155
- PAR ID:
- 10406106
- Date Published:
- Journal Name:
- Erkenntnis
- ISSN:
- 0165-0106
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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