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On the global stable manifold

Alberto Abbondandolo, Pietro Majer (2006)

Studia Mathematica

We give an alternative proof of the stable manifold theorem as an application of the (right and left) inverse mapping theorem on a space of sequences. We investigate the diffeomorphism class of the global stable manifold, a problem which in the general Banach setting gives rise to subtle questions about the possibility of extending germs of diffeomorphisms.

On the group of real analytic diffeomorphisms

Takashi Tsuboi (2009)

Annales scientifiques de l'École Normale Supérieure

The group of real analytic diffeomorphisms of a real analytic manifold is a rich group. It is dense in the group of smooth diffeomorphisms. Herman showed that for the n -dimensional torus, its identity component is a simple group. For U ( 1 ) fibered manifolds, for manifolds admitting special semi-free U ( 1 ) actions and for 2- or 3-dimensional manifolds with nontrivial U ( 1 ) actions, we show that the identity component of the group of real analytic diffeomorphisms is a perfect group.

On the Helmholtz operator of variational calculus in fibered-fibered manifolds

W. M. Mikulski (2007)

Annales Polonici Mathematici

A fibered-fibered manifold is a surjective fibered submersion π: Y → X between fibered manifolds. For natural numbers s ≥ r ≤ q an (r,s,q)th order Lagrangian on a fibered-fibered manifold π: Y → X is a base-preserving morphism λ : J r , s , q Y d i m X T * X . For p= max(q,s) there exists a canonical Euler morphism ( λ ) : J r + s , 2 s , r + p Y * Y d i m X T * X satisfying a decomposition property similar to the one in the fibered manifold case, and the critical fibered sections σ of Y are exactly the solutions of the Euler-Lagrange equation ( λ ) j r + s , 2 s , r + p σ = 0 . In the present paper, similarly...

On the homeomorphism groups of manifolds and their universal coverings

Agnieszka Kowalik, Tomasz Rybicki (2011)

Open Mathematics

Let H c(M) stand for the path connected identity component of the group of all compactly supported homeomorphisms of a manifold M. It is shown that H c(M) is perfect and simple under mild assumptions on M. Next, conjugation-invariant norms on Hc(M) are considered and the boundedness of Hc(M) and its subgroups is investigated. Finally, the structure of the universal covering group of Hc(M) is studied.

On the homotopy type of Diff ( M n ) and connected problems

Dan Burghelea (1973)

Annales de l'institut Fourier

This paper reports on some results concerning:a) The homotopy type of the group of diffeomorphisms Diff ( M n ) of a differentiable compact manifold M n (with C -topology).b) the result of the homotopy comparison of this space with the group of all homeomorphisms Homeo M n (with C o -topology). As a biproduct, one gets new facts about the homotopy groups of Diff ( D n , D n ) , Top n , Top n / O n and about the number of connected components of the space of topological and combinatorial pseudoisotopies.The results are contained in Section 1 and Section...

On the horizontal cohomology with general coefficients

Marvan, Michal (1990)

Proceedings of the Winter School "Geometry and Physics"

[For the entire collection see Zbl 0699.00032.] A new cohomology theory suitable for understanding of nonlinear partial differential equations is presented. This paper is a continuation of the following paper of the author [Differ. geometry and its appl., Proc. Conf., Brno/Czech. 1986, Commun., 235-244 (1987; Zbl 0629.58033)].

On the Hyperbolicity Domain of the Polynomial x^n + a1x^(n-1) + 1/4+ an

Kostov, Vladimir (1999)

Serdica Mathematical Journal

∗ Partially supported by INTAS grant 97-1644We consider the polynomial Pn = x^n + a1 x^(n−1) + · · · + an , ai ∈ R. We represent by figures the projections on Oa1 . . . ak , k ≤ 6, of its hyperbolicity domain Π = {a ∈ Rn | all roots of Pn are real}. The set Π and its projections Πk in the spaces Oa1 . . . ak , k ≤ n, have the structure of stratified manifolds, the strata being defined by the multiplicity vectors. It is known that for k > 2 every non-empty fibre of the projection Π^k → Π^(k−1) is...

On the index of nonlocal elliptic operators for compact Lie groups

Anton Savin (2011)

Open Mathematics

We consider a class of nonlocal operators associated with a compact Lie group G acting on a smooth manifold. A notion of symbol of such operators is introduced and an index formula for elliptic elements is obtained. The symbol in this situation is an element of a noncommutative algebra (crossed product by G) and to obtain an index formula, we define the Chern character for this algebra in the framework of noncommutative geometry.

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