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Homotopické struktury v algebře, geometrii a matematické fyzice
Černohorská, Eva ; Markl, Martin (advisor) ; Somberg, Petr (referee)
Title: Homotopic structures in algebra, geometry and mathematical physics Author: Eva Černohorská Department: Mathematical Institute of Charles University Supervisor: RNDr. Martin Markl, DrSc., Institute of Mathematics of the Academy of Sciences of the Czech Republic, Mathematical Institute of Charles University Abstract: The aim of this thesis was to generalize the result that associative algebras on finite dimensional vector spaces can be described using differentials on free algebras. This result is limited by the duality of vector spaces. If we assume that the underlying space has a linear topology, then we can use the duality between discrete and linearly compact (profinite) vector spaces. To generalize the notion of an algebra, we need to recall the completed tensor product on linear vector spaces. Since this topics does not seem to be sufficiently covered by the literature, this thesis could serve also as a comprehensive text on linear vector spaces and their completed tensor products. We prove that also A∞ structures on linearly compact vector spaces could be represented by differentials on a free algebra. Keywords: Strongly homotopy associative algebra, linear topological vector space, Pontryagin duality, completed tensor product, differential
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(Conformal) Killing spinor valued forms on Riemannian manifolds
Zima, Petr ; Somberg, Petr (advisor) ; Krýsl, Svatopluk (referee)
The goal of the present thesis is to introduce on a Riemannian Spin- manifold a system of partial differential equations for spinor-valued differ- ential forms called Killing equations. We study basic properties of several types of Killing fields and relationships among them. We provide a simple construction of Killing spinor-valued forms from Killing spinors and Killing forms. We also review the construction of metric cone and discuss the re- lationship between Killing spinor-valued forms on the base manifold and parallel spinor-valued forms on the metric cone.
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Ricci flow and geometric analysis on manifolds
Eliáš, Jakub ; Somberg, Petr (advisor) ; Salač, Tomáš (referee)
Title: Ricci flow and geometric analysis on manifolds Author: Jakub Eliáš Ústav: Matematický ústav UK Supervisor: doc. RNDr. Petr Somberg Ph.D., Matematický ústav UK Abstract: This thesis discusses basis aspects of the Ricci flow on manifolds with a view towards the ambient space construction. We start with the back- ground review of the Riemannian geometry and parabolic partial differential equations, and the Ricci flow problem on manifolds is established. Then we aim towards the formulation of the Ricci flow problem on ambient spaces and provide several basic examples. There are two main parts: the first consists of general theory needed to formulate our problem and strategy, while the second part consists of particular calculations associated with the Ricci flow problem. Keywords: Ricci flow, Ambient space, Ambient metric, Poincaré-Einstein metric. 1
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Operadic resolutions of diagrams
Doubek, Martin ; Markl, Martin (advisor) ; Somberg, Petr (referee) ; Čadek, Martin (referee)
of the Doctoral Thesis Operadic Resolutions of Diagrams by Martin Doubek We study resolutions of the operad AC describing diagrams of a given shape C in the category of algebras of a given type A. We prove the conjecture by Markl on constructing the resolution out of resolutions of A and C, at least in a certain restricted setting. For associative algebras, we make explicit the cohomology theory for the diagrams and recover Gerstenhaber-Schack diagram cohomology. In general, we show that the operadic cohomology is Ext in the category of operadic modules. 1
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Applications of invariant operators in real parabolic geometries
Púček, Roland ; Souček, Vladimír (advisor) ; Somberg, Petr (referee)
In Riemannian geometry, the fundamental fact is that there exists a unique torsion-free connection (called the Levi-Civita connection) compatible with the Riemannian metric g, i.e. having the property ∇g = 0. In projective geometry, the class of covariant derivatives defining the geometry is fixed and all these covariant derivatives have the same class of (non- parametrized) geodesics. Old (and non-trivial) problem is to find whether these curves are geodesics of a (pseudo-)Riemannian metric. Such projective structures are called metrizable. Surprisingly enough, U. Dini and R. Liu- oville found in 19th century that the metrizability problem leads to a system of linear PDE's. In the last years, there were several papers dealing with these problems. The projective geometry is a representative example of the so called parabolic geometries (for full description, see the recent monograph by A. Čap and J. Slovák). It was realized recently that the corresponding linear metrizability operator is a special example of the so called first BGG operator. The flat model of projective geometry is the (real) projective space. In this more general context, the metrizability problem for (pseudo- )Riemannian geometries is naturally generalized to the sub-Riemannian situation. In the recent preprint, D.Calderbank, J....
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Ricci flow and geometric analysis on manifolds
Eliáš, Jakub ; Somberg, Petr (advisor) ; Salač, Tomáš (referee)
Title: Ricci flow and geometric analysis on manifolds Author: Jakub Eliáš Ústav: Matematický ústav UK Supervisor: doc. RNDr. Petr Somberg Ph.D., Matematický ústav UK Abstract: This thesis discusses basis aspects of the Ricci flow on manifolds with a view towards the ambient space construction. We start with the back- ground review of the Riemannian geometry and parabolic partial differential equations, and the Ricci flow problem on manifolds is established. Then we aim towards the formulation of the Ricci flow problem on ambient spaces and provide several basic examples. There are two main parts: the first consists of general theory needed to formulate our problem and strategy, while the second part consists of particular calculations associated with the Ricci flow problem. Keywords: Ricci flow, Ambient space, Ambient metric, Poincaré-Einstein metric. 1
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(Conformal) Killing spinor valued forms on Riemannian manifolds
Zima, Petr ; Somberg, Petr (advisor) ; Krýsl, Svatopluk (referee)
The goal of the present thesis is to introduce on a Riemannian Spin- manifold a system of partial differential equations for spinor-valued differ- ential forms called Killing equations. We study basic properties of several types of Killing fields and relationships among them. We provide a simple construction of Killing spinor-valued forms from Killing spinors and Killing forms. We also review the construction of metric cone and discuss the re- lationship between Killing spinor-valued forms on the base manifold and parallel spinor-valued forms on the metric cone.
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