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Lee Smolin is an American theoretical physicist, a faculty member at the Perimeter Institute for Theoretical Physics, an adjunct professor of physics at the University of Waterloo, and a member of the graduate faculty of the philosophy department at the University of Toronto. Smolin's 2006 book The Trouble with Physics criticized string theory as a viable scientific theory. He has made contributions to quantum gravity theory, in particular the approach known as loop quantum gravity. He advocates that the two primary approaches to quantum gravity, loop quantum gravity and string theory, can be reconciled as different aspects of the same underlying theory. He also advocates an alternative view on space and time that he calls temporal naturalism. His research interests also include cosmology, elementary particle theory, the foundations of quantum mechanics, and theoretical biology.
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In physics, Born reciprocity, also called reciprocal relativity or Born–Green reciprocity, is a principle set up by theoretical physicist Max Born that calls for a duality-symmetry among space and momentum. Born and his co-workers expanded his principle to a framework that is also known as reciprocity theory.
In theoretical physics, the problem of time is a conceptual conflict between general relativity and quantum mechanics in that quantum mechanics regards the flow of time as universal and absolute, whereas general relativity regards the flow of time as malleable and relative. This problem raises the question of what time really is in a physical sense and whether it is truly a real, distinct phenomenon. It also involves the related question of why time seems to flow in a single direction, despite the fact that no known physical laws at the microscopic level seem to require a single direction.
References
- 1 2 Freidel, Laurent; Krasnov, Kirill (21 June 2008). "A new spin foam model for 4D gravity". Classical and Quantum Gravity. 25 (12): 125018. arXiv: 0708.1595 . Bibcode:2008CQGra..25l5018F. doi:10.1088/0264-9381/25/12/125018. S2CID 119138842.
- ↑ "Laurent Freidel's homepage at Perimeter Institute".
- ↑ Freidel, Laurent; Louapre, David (21 December 2004). "Ponzano–Regge model revisited: I. Gauge fixing, observables and interacting spinning particles". Classical and Quantum Gravity. 21 (24): 5685–5726. arXiv: hep-th/0401076 . Bibcode:2004CQGra..21.5685F. doi:10.1088/0264-9381/21/24/002. S2CID 42369187.
- ↑ Amelino-Camelia, Giovanni; Freidel, Laurent; Kowalski-Glikman, Jerzy; Smolin, Lee (October 2011). "Principle of relative locality". Physical Review D. 84 (8): 084010. arXiv: 1101.0931 . Bibcode:2011PhRvD..84h4010A. doi:10.1103/PhysRevD.84.084010. S2CID 49921081.
- ↑ Freidel, Laurent; Leigh, Robert; Minic, Djordje (2015). "Metastring Theory and Modular Space-time". Journal of High Energy Physics. 2015 (6): 6. arXiv: 1502.08005 . Bibcode:2015JHEP...06..006F. doi:10.1007/JHEP06(2015)006. S2CID 55570067.
