共查询到20条相似文献,搜索用时 156 毫秒
1.
Zbigniew Jelonek 《Monatshefte für Mathematik》2013,171(3-4):351-355
We give a simple direct proof of the Kleiman Bertini theorem in arbitrary characteristic. We also give a simple proof of Serre splitting theorem. 相似文献
2.
Shu-Yu Hsu 《Geometriae Dedicata》2013,162(1):375-388
We give a simple proof for the rotational symmetry of ancient solutions of Ricci flow on surfaces. As a consequence we obtain a simple proof of some results of Daskalopoulos, Hamilton and Sesum on the a priori estimates for the ancient solutions of Ricci flow on surfaces. We also give a simple proof for the solution to be a Rosenau solution under some mild conditions on the solutions of Ricci flow on surfaces. 相似文献
3.
We give a new proof of the fact that Gaussian concentration implies the logarithmic Sobolev inequality when the curvature is bounded from below, and also that exponential concentration implies Poincaré inequality under null curvature condition. Our proof holds on non-smooth structures, such as length spaces, and provides a universal control of the constants. We also give a new proof of the equivalence between dimension free Gaussian concentration and Talagrand's transport inequality. 相似文献
4.
Roussel and Rubio proved a lemma which is essential in the proof of the Strong Perfect Graph Theorem. We give a new short proof of the main case of this lemma. In this note, we also give a short proof of Hayward’s decomposition theorem for weakly chordal graphs, relying on a Roussel–Rubio-type lemma. We recall how Roussel–Rubio-type lemmas yield very short proofs of the existence of even pairs in weakly chordal graphs and Meyniel graphs. 相似文献
5.
We give an elementary proof, using nonstandard analysis, of the Jordan curve theorem. We also give a nonstandard generalization of the theorem. The proof is purely geometrical in character, without any use of topological concepts and is based on a discrete finite form of the Jordan theorem, whose proof is purely combinatorial.Some familiarity with nonstandard analysis is assumed. The rest of the paper is self-contained except for the proof a discrete standard form of the Jordan theorem. The proof is based on hyperfinite approximations to regions on the plane.Research of the first author partially supported by FONDECYT Grant # 91-1208 and of the second author, by FONDECYT Grant # 90-0647. 相似文献
6.
Daniel Smania 《Transactions of the American Mathematical Society》2006,358(4):1827-1846
We give a new proof of the hyperbolicity of the fixed point for the period-doubling renormalization operator using the local dynamics near a semi-attractive fixed point (in a Banach space) and the theory of holomorphic motions. We also give a new proof of the exponential contraction of the Feigenbaum renormalization operator in the hybrid class of the period-doubling fixed point: our proof uses the non-existence of invariant line fields in the period-doubling tower (C. McMullen), the topological convergence (D. Sullivan), and a new infinitesimal argument.
7.
In this paper we give combinatorial proofs of some well known identities and obtain some generalizations. We give a visual proof of a result of Chapman and Costas-Santos regarding the determinant of sum of matrices. Also we find a new identity expressing the permanent of sum of matrices. Besides, we give a graph theoretic proof of the Newton–Girard identity in a generalized form. 相似文献
8.
The aim of this note is to give a direct proof of the fact that the Steinberg formula holds for the Vaserstein symbol and the universal weak Mennicke symbol. We also give an alternate proof of the fact that the Steinberg formula holds for the Vaserstein symbol. 相似文献
9.
Y. Fujita 《Applied Mathematics and Optimization》2000,41(1):1-7
We give a simple proof of the theorem concerning optimality in a one-dimensional ergodic control problem. We characterize
the optimal control in the class of all Markov controls. Our proof is probabilistic and does not need to solve the corresponding
Bellman equation. This simplifies the proof.
Accepted 24 March 1998 相似文献
10.
We give a new proof of Fitzgerald's criterion for primitive polynomials over a finite field. Existing proofs essentially use the theory of linear recurrences over finite fields. Here, we give a much shorter and self-contained proof which does not use the theory of linear recurrences. 相似文献
11.
Sudip Bera 《Linear and Multilinear Algebra》2018,66(8):1659-1667
In this paper, we give combinatorial proofs of some determinantal identities. In fact, we give a combinatorial proof of a theorem of R. P. Stanley regarding the enumeration of paths in acyclic digraphs along with some interesting applications. We also give an almost visual proof of a recent result of Oliver Knill, namely ‘The generalized Cauchy–Binet Theorem.’ 相似文献
12.
J.B. Remmel 《Linear and Multilinear Algebra》1982,11(1):45-100
We give a bijective proof of a formula due independently to Frobenius and Young for the number of standard Young tableau of shape λ for λ any partition. Frame, Robinson, and Thrall derived their hook formula for the number of standard Young tableau from the Frobenius-Young formula. As a corollary to our bijective proof of the Frobenius-Young formula, we also give a bijective proof of the Frame-Robinson-Thrall hook formula. 相似文献
13.
Ian F. Putnam 《Expositiones Mathematicae》2010,28(2):101-131
We give a new proof of the classification, up to topological orbit equivalence, of minimal AF-equivalence relations and minimal actions of the group of integers on the Cantor set. This proof relies heavily on the structure of AF-equivalence relations and the theory of dimension groups; we give a short survey of these topics. 相似文献
14.
Adrien Boyer 《Comptes Rendus Mathematique》2013,351(9-10):335-338
We give a short elementary proof of the fact that connected semisimple real Lie groups satisfy property RD. The proof is based on a process of linearisation. 相似文献
15.
E. Kochneff 《Proceedings of the American Mathematical Society》1996,124(5):1539-1547
We calculate an integral formula for the Hermite projection operators. We give some applications of our formula. We also give a short proof of a recent theorem of Thangavelu.
16.
Jürgen Elstrodt 《manuscripta mathematica》2006,121(4):457-459
We give a very simple proof of a classical transformation formula for the Dedekind eta function. This proof is a simplified version of an approach suggested by H. Petersson. 相似文献
17.
Santi Spadaro 《Topology and its Applications》2011,158(16):2091-2093
We give a simple proof of the increasing strengthening of Arhangel?skii Theorem. Our proof naturally leads to a refinement of this result of Juhász. 相似文献
18.
ANewProoffortheInterpolatingTheoremSunShunhua(孙顺华)andYuDahai(余大海)(DepartmentofMathematics,SichuanUniversity,Chengdu,610064)Ab... 相似文献
19.
Tomonari Suzuki 《Journal of Mathematical Analysis and Applications》2008,340(1):752-755
We give an example which says that Mizoguchi-Takahashi's fixed point theorem for set-valued mappings is a real generalization of Nadler's. We also give a very simple proof of Mizoguchi-Takahashi's theorem. 相似文献
20.
R V Gurjar 《Proceedings Mathematical Sciences》1997,107(3):237-242
We give a different proof of a formula of Suzuki and its strengthening by Zaidenberg for the topological Euler characteristic
of an affine surface fibered over a curve. We deduce this formula using the ideas for the proof of an analogous formula for
a proper morphism. 相似文献