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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 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 theoretical physics, a mass generation mechanism is a theory that describes the origin of mass from the most fundamental laws of physics. Physicists have proposed a number of models that advocate different views of the origin of mass. The problem is complicated because the primary role of mass is to mediate gravitational interaction between bodies, and no theory of gravitational interaction reconciles with the currently popular Standard Model of particle physics.
Relative locality is a proposed physical phenomenon in which different observers would disagree on whether two space-time events are coincident. This is in contrast to special relativity and general relativity in which different observers may disagree on whether two distant events occur at the same time but if an observer infers that two events are at the same spacetime position then all observers will agree.
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. For macroscopic systems the directionality of time is directly linked to first principles such as the second law of thermodynamics.
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.
