Aldrovandi, R. [UNESP]Pereira, J. G. [UNESP]2013-09-302014-05-202013-09-302014-05-202009-01-01Foundations of Physics. New York: Springer, v. 39, n. 1, p. 1-19, 2009.0015-9018http://hdl.handle.net/11449/24169The Poincar, group generalizes the Galilei group for high-velocity kinematics. The de Sitter group is assumed to go one step further, generalizing Poincar, as the group governing high-energy kinematics. In other words, ordinary special relativity is here replaced by de Sitter relativity. In this theory, the cosmological constant I > is no longer a free parameter, and can be determined in terms of other quantities. When applied to the whole universe, it is able to predict the value of I > and to explain the cosmic coincidence. When applied to the propagation of ultra-high energy photons, it gives a good estimate of the time delay observed in extragalactic gamma-ray flares. It can, for this reason, be considered a new paradigm to approach the quantum gravity problem.engde Sitter relativityCosmological constantQuantum gravityArtigo10.1007/s10701-008-9258-5WOS:000262315200001Acesso restrito1599966126072450