The $abc$-Problem for Gabor Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook The $abc$-Problem for Gabor Systems write by Xin-Rong Dai. This book was released on 2016-10-05. The $abc$-Problem for Gabor Systems available in PDF, EPUB and Kindle. A longstanding problem in Gabor theory is to identify time-frequency shifting lattices aZ×bZ and ideal window functions χI on intervals I of length c such that {e−2πinbtχI(t−ma): (m,n)∈Z×Z} are Gabor frames for the space of all square-integrable functions on the real line. In this paper, the authors create a time-domain approach for Gabor frames, introduce novel techniques involving invariant sets of non-contractive and non-measure-preserving transformations on the line, and provide a complete answer to the above abc-problem for Gabor systems.
Excursions in Harmonic Analysis, Volume 3
Excursions in Harmonic Analysis, Volume 3 - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Excursions in Harmonic Analysis, Volume 3 write by Radu Balan. This book was released on 2015-06-02. Excursions in Harmonic Analysis, Volume 3 available in PDF, EPUB and Kindle. This volume consists of contributions spanning a wide spectrum of harmonic analysis and its applications written by speakers at the February Fourier Talks from 2002 – 2013. Containing cutting-edge results by an impressive array of mathematicians, engineers, and scientists in academia, industry, and government, it will be an excellent reference for graduate students, researchers, and professionals in pure and applied mathematics, physics, and engineering. Topics covered include · spectral analysis and correlation; · radar and communications: design, theory, and applications; · sparsity · special topics in harmonic analysis. The February Fourier Talks are held annually at the Norbert Wiener Center for Harmonic Analysis and Applications. Located at the University of Maryland, College Park, the Norbert Wiener Center provides a state-of- the-art research venue for the broad emerging area of mathematical engineering.
Topologically Protected States in One-Dimensional Systems
Topologically Protected States in One-Dimensional Systems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Topologically Protected States in One-Dimensional Systems write by Charles Fefferman. This book was released on 2017-04-25. Topologically Protected States in One-Dimensional Systems available in PDF, EPUB and Kindle. The authors study a class of periodic Schrodinger operators, which in distinguished cases can be proved to have linear band-crossings or ``Dirac points''. They then show that the introduction of an ``edge'', via adiabatic modulation of these periodic potentials by a domain wall, results in the bifurcation of spatially localized ``edge states''. These bound states are associated with the topologically protected zero-energy mode of an asymptotic one-dimensional Dirac operator. The authors' model captures many aspects of the phenomenon of topologically protected edge states for two-dimensional bulk structures such as the honeycomb structure of graphene. The states the authors construct can be realized as highly robust TM-electromagnetic modes for a class of photonic waveguides with a phase-defect.
Rationality Problem for Algebraic Tori
Rationality Problem for Algebraic Tori - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Rationality Problem for Algebraic Tori write by Akinari Hoshi. This book was released on 2017-07-13. Rationality Problem for Algebraic Tori available in PDF, EPUB and Kindle. The authors give the complete stably rational classification of algebraic tori of dimensions and over a field . In particular, the stably rational classification of norm one tori whose Chevalley modules are of rank and is given. The authors show that there exist exactly (resp. , resp. ) stably rational (resp. not stably but retract rational, resp. not retract rational) algebraic tori of dimension , and there exist exactly (resp. , resp. ) stably rational (resp. not stably but retract rational, resp. not retract rational) algebraic tori of dimension . The authors make a procedure to compute a flabby resolution of a -lattice effectively by using the computer algebra system GAP. Some algorithms may determine whether the flabby class of a -lattice is invertible (resp. zero) or not. Using the algorithms, the suthors determine all the flabby and coflabby -lattices of rank up to and verify that they are stably permutation. The authors also show that the Krull-Schmidt theorem for -lattices holds when the rank , and fails when the rank is ...
Maximal Cohen-Macaulay Modules Over Non-Isolated Surface Singularities and Matrix Problems
Maximal Cohen-Macaulay Modules Over Non-Isolated Surface Singularities and Matrix Problems - read free eBook in online reader or directly download on the web page. Select files or add your book in reader. Download and read online ebook Maximal Cohen-Macaulay Modules Over Non-Isolated Surface Singularities and Matrix Problems write by Igor Burban. This book was released on 2017-07-13. Maximal Cohen-Macaulay Modules Over Non-Isolated Surface Singularities and Matrix Problems available in PDF, EPUB and Kindle. In this article the authors develop a new method to deal with maximal Cohen–Macaulay modules over non–isolated surface singularities. In particular, they give a negative answer on an old question of Schreyer about surface singularities with only countably many indecomposable maximal Cohen–Macaulay modules. Next, the authors prove that the degenerate cusp singularities have tame Cohen–Macaulay representation type. The authors' approach is illustrated on the case of k as well as several other rings. This study of maximal Cohen–Macaulay modules over non–isolated singularities leads to a new class of problems of linear algebra, which the authors call representations of decorated bunches of chains. They prove that these matrix problems have tame representation type and describe the underlying canonical forms.
