Author: Camillo De LellisPublisher:
ISBN: 9781470406080
Category : MATHEMATICS
Languages : en
Pages : 79
Book Description
Q-valued Functions Revisited
Author: Camillo De LellisPublisher:
ISBN: 9781470406080
Category : MATHEMATICS
Languages : en
Pages : 79
Book Description
Q-valued Functions Revisited
Author: Camillo De LellisPublisher: American Mathematical Soc.
ISBN: 0821874187
Category : Mathematics
Languages : en
Pages : 92
Book Description
In this memoir the authors revisit Almgren's theory of Q-valued functions.
$Q$-Valued Functions Revisited
Author: Camillo De LellisPublisher: American Mathematical Soc.
ISBN: 082184914X
Category : Mathematics
Languages : en
Pages : 92
Book Description
In this memoir the authors revisit Almgren's theory of $Q$-valued functions, which are functions taking values in the space $\mathcal{A}_Q(\mathbb{R}^{n})$ of unordered $Q$-tuples of points in $\mathbb{R}^{n}$. In particular, the authors: give shorter versions of Almgren's proofs of the existence of $\mathrm{Dir}$-minimizing $Q$-valued functions, of their Holder regularity, and of the dimension estimate of their singular set; propose an alternative, intrinsic approach to these results, not relying on Almgren's biLipschitz embedding $\xi: \mathcal{A}_Q(\mathbb{R}^{n})\to\mathbb{R}^{N(Q,n)}$; improve upon the estimate of the singular set of planar $\mathrm{D}$-minimizing functions by showing that it consists of isolated points.
Almgren's Q-valued Functions Revisited
Author: Camillo De Lellis
Author: On $L$-Packets for Inner Forms of $SL_n$
Author: Kaoru HiragaPublisher: American Mathematical Soc.
ISBN: 0821853643
Category : Mathematics
Languages : en
Pages : 110
Book Description
The theory of $L$-indistinguishability for inner forms of $SL_2$ has been established in the well-known paper of Labesse and Langlands (L-indistinguishability forSL$(2)$. Canad. J. Math. 31 (1979), no. 4, 726-785). In this memoir, the authors study $L$-indistinguishability for inner forms of $SL_n$ for general $n$. Following the idea of Vogan in (The local Langlands conjecture. Representation theory of groups and algebras, 305-379, Contemp. Math. 145 (1993)), they modify the $S$-group and show that such an $S$-group fits well in the theory of endoscopy for inner forms of $SL_n$.
Multicurves and Equivariant Cohomology
Author: Neil P. StricklandPublisher: American Mathematical Soc.
ISBN: 0821849018
Category : Mathematics
Languages : en
Pages : 130
Book Description
Let $A$ be a finite abelian group. The author sets up an algebraic framework for studying $A$-equivariant complex-orientable cohomology theories in terms of a suitable kind of equivariant formal group. He computes the equivariant cohomology of many spaces in these terms, including projective bundles (and associated Gysin maps), Thom spaces, and infinite Grassmannians.
Chevalley Supergroups
Author: Rita FioresiPublisher: American Mathematical Soc.
ISBN: 0821853007
Category : Mathematics
Languages : en
Pages : 77
Book Description
In the framework of algebraic supergeometry, the authors give a construction of the scheme-theoretic supergeometric analogue of split reductive algebraic group-schemes, namely affine algebraic supergroups associated to simple Lie superalgebras of classical type. In particular, all Lie superalgebras of both basic and strange types are considered. This provides a unified approach to most of the algebraic supergroups considered so far in the literature, and an effective method to construct new ones. The authors' method follows the pattern of a suitable scheme-theoretic revisitation of Chevalley's construction of semisimple algebraic groups, adapted to the reductive case. As an intermediate step, they prove an existence theorem for Chevalley bases of simple classical Lie superalgebras and a PBW-like theorem for their associated Kostant superalgebras.
On the Algebraic Foundations of Bounded Cohomology
Author: Theo BühlerPublisher: American Mathematical Soc.
ISBN: 0821853112
Category : Mathematics
Languages : en
Pages : 126
Book Description
It is a widespread opinion among experts that (continuous) bounded cohomology cannot be interpreted as a derived functor and that triangulated methods break down. The author proves that this is wrong. He uses the formalism of exact categories and their derived categories in order to construct a classical derived functor on the category of Banach $G$-modules with values in Waelbroeck's abelian category. This gives us an axiomatic characterization of this theory for free, and it is a simple matter to reconstruct the classical semi-normed cohomology spaces out of Waelbroeck's category. The author proves that the derived categories of right bounded and of left bounded complexes of Banach $G$-modules are equivalent to the derived category of two abelian categories (one for each boundedness condition), a consequence of the theory of abstract truncation and hearts of $t$-structures. Moreover, he proves that the derived categories of Banach $G$-modules can be constructed as the homotopy categories of model structures on the categories of chain complexes of Banach $G$-modules, thus proving that the theory fits into yet another standard framework of homological and homotopical algebra.
Supported Blow-Up and Prescribed Scalar Curvature on $S^n$
Author: Man Chun LeungPublisher: American Mathematical Soc.
ISBN: 0821853376
Category : Mathematics
Languages : en
Pages : 112
Book Description
The author expounds the notion of supported blow-up and applies it to study the renowned Nirenberg/Kazdan-Warner problem on $S^n$. When $n \ge 5$ and under some mild conditions, he shows that blow-up at a point with positive definite Hessian has to be a supported isolated blow-up, which, when combined with a uniform volume bound, is a removable singularity. A new asymmetric condition is introduced to exclude single simple blow-up. These enable the author to obtain a general existence theorem for $n \ge 5$ with rather natural condition.