Logarithmic Sobolev inequality for diffusion semigroups
نویسنده
چکیده
Through the main example of the Ornstein-Uhlenbeck semigroup, the Bakry-Emery criterion is presented as a main tool to get functional inequalities as Poincaré or logarithmic Sobolev inequalities. Moreover an alternative method using the optimal mass transportation, is also given to obtain the logarithmic Sobolev inequality. Mathematics Subject Classification (2000) : Primary 35B40, 35K10, 60J60.
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