Compact Quotients of Cahen-Wallach Spaces

Compact Quotients of Cahen-Wallach Spaces PDF Author: Ines Kath
Publisher: American Mathematical Soc.
ISBN: 1470441039
Category : Education
Languages : en
Pages : 96

Get Book Here

Book Description
Indecomposable symmetric Lorentzian manifolds of non-constant curvature are called Cahen-Wallach spaces. Their isometry classes are described by continuous families of real parameters. The authors derive necessary and sufficient conditions for the existence of compact quotients of Cahen-Wallach spaces in terms of these parameters.

Compact Quotients of Cahen-Wallach Spaces

Compact Quotients of Cahen-Wallach Spaces PDF Author: Ines Kath
Publisher: American Mathematical Soc.
ISBN: 1470441039
Category : Education
Languages : en
Pages : 96

Get Book Here

Book Description
Indecomposable symmetric Lorentzian manifolds of non-constant curvature are called Cahen-Wallach spaces. Their isometry classes are described by continuous families of real parameters. The authors derive necessary and sufficient conditions for the existence of compact quotients of Cahen-Wallach spaces in terms of these parameters.

Space – Time – Matter

Space – Time – Matter PDF Author: Jochen Brüning
Publisher: Walter de Gruyter GmbH & Co KG
ISBN: 3110451530
Category : Mathematics
Languages : en
Pages : 590

Get Book Here

Book Description
This monograph describes some of the most interesting results obtained by the mathematicians and physicists collaborating in the CRC 647 "Space – Time – Matter", in the years 2005 - 2016. The work presented concerns the mathematical and physical foundations of string and quantum field theory as well as cosmology. Important topics are the spaces and metrics modelling the geometry of matter, and the evolution of these geometries. The partial differential equations governing such structures and their singularities, special solutions and stability properties are discussed in detail. Contents Introduction Algebraic K-theory, assembly maps, controlled algebra, and trace methods Lorentzian manifolds with special holonomy – Constructions and global properties Contributions to the spectral geometry of locally homogeneous spaces On conformally covariant differential operators and spectral theory of the holographic Laplacian Moduli and deformations Vector bundles in algebraic geometry and mathematical physics Dyson–Schwinger equations: Fix-point equations for quantum fields Hidden structure in the form factors ofN = 4 SYM On regulating the AdS superstring Constraints on CFT observables from the bootstrap program Simplifying amplitudes in Maxwell-Einstein and Yang-Mills-Einstein supergravities Yangian symmetry in maximally supersymmetric Yang-Mills theory Wave and Dirac equations on manifolds Geometric analysis on singular spaces Singularities and long-time behavior in nonlinear evolution equations and general relativity

Global Well-Posedness of High Dimensional Maxwell–Dirac for Small Critical Data

Global Well-Posedness of High Dimensional Maxwell–Dirac for Small Critical Data PDF Author: Cristian Gavrus
Publisher: American Mathematical Soc.
ISBN: 147044111X
Category : Education
Languages : en
Pages : 106

Get Book Here

Book Description
In this paper, the authors prove global well-posedness of the massless Maxwell–Dirac equation in the Coulomb gauge on R1+d(d≥4) for data with small scale-critical Sobolev norm, as well as modified scattering of the solutions. Main components of the authors' proof are A) uncovering null structure of Maxwell–Dirac in the Coulomb gauge, and B) proving solvability of the underlying covariant Dirac equation. A key step for achieving both is to exploit (and justify) a deep analogy between Maxwell–Dirac and Maxwell-Klein-Gordon (for which an analogous result was proved earlier by Krieger-Sterbenz-Tataru, which says that the most difficult part of Maxwell–Dirac takes essentially the same form as Maxwell-Klein-Gordon.

Global Smooth Solutions for the Inviscid SQG Equation

Global Smooth Solutions for the Inviscid SQG Equation PDF Author: Angel Castro
Publisher: American Mathematical Soc.
ISBN: 1470442140
Category : Mathematics
Languages : en
Pages : 102

Get Book Here

Book Description
In this paper, the authors show the existence of the first non trivial family of classical global solutions of the inviscid surface quasi-geostrophic equation.

Dynamics Near the Subcritical Transition of the 3D Couette Flow I: Below Threshold Case

Dynamics Near the Subcritical Transition of the 3D Couette Flow I: Below Threshold Case PDF Author: Jacob Bedrossian
Publisher: American Mathematical Soc.
ISBN: 1470442175
Category : Mathematics
Languages : en
Pages : 170

Get Book Here

Book Description
The authors study small disturbances to the periodic, plane Couette flow in the 3D incompressible Navier-Stokes equations at high Reynolds number Re. They prove that for sufficiently regular initial data of size $epsilon leq c_0mathbf {Re}^-1$ for some universal $c_0 > 0$, the solution is global, remains within $O(c_0)$ of the Couette flow in $L^2$, and returns to the Couette flow as $t rightarrow infty $. For times $t gtrsim mathbf {Re}^1/3$, the streamwise dependence is damped by a mixing-enhanced dissipation effect and the solution is rapidly attracted to the class of ``2.5 dimensional'' streamwise-independent solutions referred to as streaks.

Conformal Graph Directed Markov Systems on Carnot Groups

Conformal Graph Directed Markov Systems on Carnot Groups PDF Author: Vasileios Chousionis
Publisher: American Mathematical Soc.
ISBN: 1470442159
Category : Mathematics
Languages : en
Pages : 170

Get Book Here

Book Description
The authors develop a comprehensive theory of conformal graph directed Markov systems in the non-Riemannian setting of Carnot groups equipped with a sub-Riemannian metric. In particular, they develop the thermodynamic formalism and show that, under natural hypotheses, the limit set of an Carnot conformal GDMS has Hausdorff dimension given by Bowen's parameter. They illustrate their results for a variety of examples of both linear and nonlinear iterated function systems and graph directed Markov systems in such sub-Riemannian spaces. These include the Heisenberg continued fractions introduced by Lukyanenko and Vandehey as well as Kleinian and Schottky groups associated to the non-real classical rank one hyperbolic spaces.

Explicit Arithmetic of Jacobians of Generalized Legendre Curves Over Global Function Fields

Explicit Arithmetic of Jacobians of Generalized Legendre Curves Over Global Function Fields PDF Author: Lisa Berger
Publisher: American Mathematical Soc.
ISBN: 1470442191
Category : Mathematics
Languages : en
Pages : 144

Get Book Here

Book Description
The authors study the Jacobian $J$ of the smooth projective curve $C$ of genus $r-1$ with affine model $y^r = x^r-1(x + 1)(x + t)$ over the function field $mathbb F_p(t)$, when $p$ is prime and $rge 2$ is an integer prime to $p$. When $q$ is a power of $p$ and $d$ is a positive integer, the authors compute the $L$-function of $J$ over $mathbb F_q(t^1/d)$ and show that the Birch and Swinnerton-Dyer conjecture holds for $J$ over $mathbb F_q(t^1/d)$.

Filtrations and Buildings

Filtrations and Buildings PDF Author: Christophe Cornut
Publisher: American Mathematical Soc.
ISBN: 1470442213
Category : Mathematics
Languages : en
Pages : 162

Get Book Here

Book Description
The author constructs and studies a scheme theoretical version of the Tits vectorial building, relates it to filtrations on fiber functors, and uses them to clarify various constructions pertaining to affine Bruhat-Tits buildings, for which he also provides a Tannakian description.

Subgroup Decomposition in Out(Fn)

Subgroup Decomposition in Out(Fn) PDF Author: Michael Handel
Publisher: American Mathematical Soc.
ISBN: 1470441136
Category : Education
Languages : en
Pages : 290

Get Book Here

Book Description
In this work the authors develop a decomposition theory for subgroups of Out(Fn) which generalizes the decomposition theory for individual elements of Out(Fn) found in the work of Bestvina, Feighn, and Handel, and which is analogous to the decomposition theory for subgroups of mapping class groups found in the work of Ivanov.

The Triangle-Free Process and the Ramsey Number R(3,k)

The Triangle-Free Process and the Ramsey Number R(3,k) PDF Author: Gonzalo Fiz Pontiveros
Publisher: American Mathematical Soc.
ISBN: 1470440717
Category : Education
Languages : en
Pages : 138

Get Book Here

Book Description
The areas of Ramsey theory and random graphs have been closely linked ever since Erdős's famous proof in 1947 that the “diagonal” Ramsey numbers R(k) grow exponentially in k. In the early 1990s, the triangle-free process was introduced as a model which might potentially provide good lower bounds for the “off-diagonal” Ramsey numbers R(3,k). In this model, edges of Kn are introduced one-by-one at random and added to the graph if they do not create a triangle; the resulting final (random) graph is denoted Gn,△. In 2009, Bohman succeeded in following this process for a positive fraction of its duration, and thus obtained a second proof of Kim's celebrated result that R(3,k)=Θ(k2/logk). In this paper the authors improve the results of both Bohman and Kim and follow the triangle-free process all the way to its asymptotic end.