In 2010,Gábor Czédli and E.Tamás Schmidt mentioned that the best cover-preserving embedding of a given semimodular lattice is not known yet[A cover-preserving embedding of semimodular lattices into geom...In 2010,Gábor Czédli and E.Tamás Schmidt mentioned that the best cover-preserving embedding of a given semimodular lattice is not known yet[A cover-preserving embedding of semimodular lattices into geometric lattices.Advances in Mathematics,225,2455-2463(2010)].That is to say:What are the geometric lattices G such that a given finite semimodular lattice L has a cover-preserving embedding into G with the smallest|G|?In this paper,we propose an algorithm to calculate all the best extending cover-preserving geometric lattices G of a given semimodular lattice L and prove that the length and the number of atoms of every best extending cover-preserving geometric lattice G equal the length of L and the number of non-zero join-irreducible elements of L,respectively.Therefore,we solve the problem on the best cover-preserving embedding of a given semimodular lattice raised by Gábor Czédli and E.Tamás Schmidt.展开更多
In this work,we prove an optimal global-in-time L^(p)-L^(q) estimate for solutions to the Kramers-Fokker-Planck equation with short range potential in dimension three.Our result shows that the decay rate as t-→+∞ is...In this work,we prove an optimal global-in-time L^(p)-L^(q) estimate for solutions to the Kramers-Fokker-Planck equation with short range potential in dimension three.Our result shows that the decay rate as t-→+∞ is the same as the heat equation in x-variables and the divergence rate as t→O_(+) is related to the sub-ellipticity with loss of one third derivatives of the Kramers-Fokker-Planck operator.展开更多
基金Supported by the National Natural Science Foundation of China(Grant Nos.11901064 and 12071325)。
文摘In 2010,Gábor Czédli and E.Tamás Schmidt mentioned that the best cover-preserving embedding of a given semimodular lattice is not known yet[A cover-preserving embedding of semimodular lattices into geometric lattices.Advances in Mathematics,225,2455-2463(2010)].That is to say:What are the geometric lattices G such that a given finite semimodular lattice L has a cover-preserving embedding into G with the smallest|G|?In this paper,we propose an algorithm to calculate all the best extending cover-preserving geometric lattices G of a given semimodular lattice L and prove that the length and the number of atoms of every best extending cover-preserving geometric lattice G equal the length of L and the number of non-zero join-irreducible elements of L,respectively.Therefore,we solve the problem on the best cover-preserving embedding of a given semimodular lattice raised by Gábor Czédli and E.Tamás Schmidt.
文摘In this work,we prove an optimal global-in-time L^(p)-L^(q) estimate for solutions to the Kramers-Fokker-Planck equation with short range potential in dimension three.Our result shows that the decay rate as t-→+∞ is the same as the heat equation in x-variables and the divergence rate as t→O_(+) is related to the sub-ellipticity with loss of one third derivatives of the Kramers-Fokker-Planck operator.