4. the Concept of a Lie Group 4.1. the Category of Manifolds and The
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Derived Smooth Manifolds
DERIVED SMOOTH MANIFOLDS DAVID I. SPIVAK Abstract. We define a simplicial category called the category of derived man- ifolds. It contains the category of smooth manifolds as a full discrete subcat- egory, and it is closed under taking arbitrary intersections in a manifold. A derived manifold is a space together with a sheaf of local C1-rings that is obtained by patching together homotopy zero-sets of smooth functions on Eu- clidean spaces. We show that derived manifolds come equipped with a stable normal bun- dle and can be imbedded into Euclidean space. We define a cohomology theory called derived cobordism, and use a Pontrjagin-Thom argument to show that the derived cobordism theory is isomorphic to the classical cobordism theory. This allows us to define fundamental classes in cobordism for all derived man- ifolds. In particular, the intersection A \ B of submanifolds A; B ⊂ X exists on the categorical level in our theory, and a cup product formula [A] ^ [B] = [A \ B] holds, even if the submanifolds are not transverse. One can thus consider the theory of derived manifolds as a categorification of intersection theory. Contents 1. Introduction 1 2. The axioms 8 3. Main results 14 4. Layout for the construction of dMan 21 5. C1-rings 23 6. Local C1-ringed spaces and derived manifolds 26 7. Cotangent Complexes 32 8. Proofs of technical results 39 9. Derived manifolds are good for doing intersection theory 50 10. Relationship to similar work 52 References 55 1. Introduction Let Ω denote the unoriented cobordism ring (though what we will say applies to other cobordism theories as well, e.g. -
Categorical Differential Geometry Cahiers De Topologie Et Géométrie Différentielle Catégoriques, Tome 35, No 4 (1994), P
CAHIERS DE TOPOLOGIE ET GÉOMÉTRIE DIFFÉRENTIELLE CATÉGORIQUES M. V. LOSIK Categorical differential geometry Cahiers de topologie et géométrie différentielle catégoriques, tome 35, no 4 (1994), p. 274-290 <http://www.numdam.org/item?id=CTGDC_1994__35_4_274_0> © Andrée C. Ehresmann et les auteurs, 1994, tous droits réservés. L’accès aux archives de la revue « Cahiers de topologie et géométrie différentielle catégoriques » implique l’accord avec les conditions générales d’utilisation (http://www.numdam.org/conditions). Toute utilisation commerciale ou impression systématique est constitutive d’une infraction pénale. Toute copie ou impression de ce fichier doit contenir la présente mention de copyright. Article numérisé dans le cadre du programme Numérisation de documents anciens mathématiques http://www.numdam.org/ CAHIERS DE TOPOLOGIE ET VolumeXXXV-4 (1994) GEOMETRIE DIFFERENTIELLE CATEGORIQUES CATEGORICAL DIFFERENTIAL GEOMETRY by M.V. LOSIK R6sum6. Cet article d6veloppe une th6orie g6n6rale des structures g6om6triques sur des vari6t6s, bas6e sur la tlieorie des categories. De nombreuses generalisations connues des vari6t6s et des vari6t6s de Rie- mann r.entrent dans le cadre de cette th6orie g6n6rale. On donne aussi une construction des classes caractéristiques des objets ainsi obtenus, tant classiques que generalises. Diverses applications sont indiqu6es, en parti- culier aux feuilletages. Introduction This paper is the result of an attempt to give a precise meaning to some ideas of the "formal differential geometry" of Gel’fand. These ideas of Gel’fand have not been formalized in general but they may be explained by the following example. Let C*(Wn; IR) be the complex of continuous cochains of the Lie algebra Wn of formal vector fields on IRn with coefficients in the trivial Wn-module IR and let C*(Wn,GL(n, R)), C*(Wn, O(n)) be its subcomplexes of relative cochains of Wn relative to the groups GL(n, R), 0(n), respectively. -
On Colimits in Various Categories of Manifolds
ON COLIMITS IN VARIOUS CATEGORIES OF MANIFOLDS DAVID WHITE 1. Introduction Homotopy theorists have traditionally studied topological spaces and used methods which rely heavily on computation, construction, and induction. Proofs often go by constructing some horrendously complicated object (usually via a tower of increasingly complicated objects) and then proving inductively that we can understand what’s going on at each step and that in the limit these steps do what is required. For this reason, a homotopy theorist need the freedom to make any construction he wishes, e.g. products, subobjects, quotients, gluing towers of spaces together, dividing out by group actions, moving to fixed points of group actions, etc. Over the past 50 years tools have been developed which allow the study of many different categories. The key tool for this is the notion of a model category, which is the most general place one can do homotopy theory. Model categories were introduced by the Fields Medalist Dan Quillen, and the best known reference for model categories is the book Model Categories by Mark Hovey. Model categories are defined by a list of axioms which are all analogous to properties that the category Top of topological spaces satisfies. The most important property of a model category is that it has three distinguished classes of morphisms–called weak equivalences, cofibrations, and fibrations–which follow rules similar to the classes of maps with those names in the category Top (so the homotopy theory comes into play by inverting the weak equivalences to make them isomorphisms). The fact that homotopy theorists need to be able to do lots of constructions is contained in the axiom that M must be complete and cocomplete. -
Quasi-Smooth Derived Manifolds
Quasi-smooth Derived Manifolds David Isaac Spivak January 6, 2010 Abstract The category Man of smooth manifolds is not closed under arbitrary fiber products; for example the zeroset of a smooth function on a manifold is not necessarily a manifold, and the non-transverse intersection of submanifolds is not a manifold. We describe a category dMan, called the category of derived manifolds with the following properties: 1. dMan contains Man as a full subcategory; 2. dMan is closed under taking zerosets of arbitrary smooth functions (and consequently fiber products over a smooth base); and 3. every compact derived manifold has a fundamental homology class which has the desired properties. In order to accomplish this, we must incorporate homotopy theoretic meth- ods (e.g. model categories or 1-categories) with basic manifold theory. Jacob Lurie took on a similar project in his thesis, namely incorporating homotopy theory and algebraic geometry. We derive much of our inspiration from that and subsequent works by Lurie. For example, we define a derived manifold to be a structured space that can be covered by principal derived manifolds, much as a derived scheme is a structured space that can be covered by affine derived schemes. We proceed to define a cotangent complex on derived manifolds and use it to show that any derived manifold is isomorphic to the zeroset of a section of a vector bundle E ! RN . After defining derived manifolds with boundary we begin to explore the notion of derived cobordism over a topological space K. We prove two crucial facts: that any two manifolds which are derived cobordant are in fact (smoothly) cobordant, and that any derived manifold is derived cobordant over K to a smooth manifold. -
CONVENIENT CATEGORIES of SMOOTH SPACES 1. Introduction
TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY Volume 363, Number 11, November 2011, Pages 5789–5825 S 0002-9947(2011)05107-X Article electronically published on June 6, 2011 CONVENIENT CATEGORIES OF SMOOTH SPACES JOHN C. BAEZ AND ALEXANDER E. HOFFNUNG Abstract. A ‘Chen space’ is a set X equipped with a collection of ‘plots’, i.e., maps from convex sets to X, satisfying three simple axioms. While an individ- ual Chen space can be much worse than a smooth manifold, the category of all Chen spaces is much better behaved than the category of smooth manifolds. For example, any subspace or quotient space of a Chen space is a Chen space, and the space of smooth maps between Chen spaces is again a Chen space. Souriau’s ‘diffeological spaces’ share these convenient properties. Here we give a unified treatment of both formalisms. Following ideas of Penon and Dubuc, we show that Chen spaces, diffeological spaces, and even simplicial complexes are examples of ‘concrete sheaves on a concrete site’. As a result, the cate- gories of such spaces are locally Cartesian closed, with all limits, all colimits, and a weak subobject classifier. For the benefit of differential geometers, our treatment explains most of the category theory we use. 1. Introduction Algebraic topologists have become accustomed to working in a category of spaces for which many standard constructions have good formal properties: mapping spaces, subspaces and quotient spaces, limits and colimits, and so on. In differ- ential geometry the situation is quite different, since the most popular category, that of finite-dimensional smooth manifolds, lacks almost all these features. -
Category Theory
University of Cambridge Mathematics Tripos Part III Category Theory Michaelmas, 2018 Lectures by P. T. Johnstone Notes by Qiangru Kuang Contents Contents 1 Definitions and examples 2 2 The Yoneda lemma 10 3 Adjunctions 16 4 Limits 23 5 Monad 35 6 Cartesian closed categories 46 7 Toposes 54 7.1 Sheaves and local operators* .................... 61 Index 66 1 1 Definitions and examples 1 Definitions and examples Definition (category). A category C consists of 1. a collection ob C of objects A; B; C; : : :, 2. a collection mor C of morphisms f; g; h; : : :, 3. two operations dom and cod assigning to each f 2 mor C a pair of f objects, its domain and codomain. We write A −! B to mean f is a morphism and dom f = A; cod f = B, 1 4. an operation assigning to each A 2 ob C a morhpism A −−!A A, 5. a partial binary operation (f; g) 7! fg on morphisms, such that fg is defined if and only if dom f = cod g and let dom fg = dom g; cod fg = cod f if fg is defined satisfying f 1. f1A = f = 1Bf for any A −! B, 2. (fg)h = f(gh) whenever fg and gh are defined. Remark. 1. This definition is independent of any model of set theory. If we’re givena particuar model of set theory, we call C small if ob C and mor C are sets. 2. Some texts say fg means f followed by g (we are not). 3. Note that a morphism f is an identity if and only if fg = g and hf = h whenever the compositions are defined so we could formulate the defini- tions entirely in terms of morphisms. -
Factorization Homology of Topological Manifolds
FACTORIZATION HOMOLOGY OF TOPOLOGICAL MANIFOLDS DAVID AYALA & JOHN FRANCIS Abstract. Factorization homology theories of topological manifolds, after Beilinson, Drinfeld and Lurie, are homology-type theories for topological n-manifolds whose coefficient systems are n-disk algebras or n-disk stacks. In this work we prove a precise formulation of this idea, giving an axiomatic characterization of factorization homology with coefficients in n-disk algebras in terms of a generalization of the Eilenberg{Steenrod axioms for singular homology. Each such theory gives rise to a kind of topological quantum field theory, for which observables can be defined on general n-manifolds and not only closed n-manifolds. For n-disk algebra coefficients, these field theories are characterized by the condition that global observables are determined by local observables in a strong sense. Our axiomatic point of view has a number of applications. In particular, we give a concise proof of the nonabelian Poincar´eduality of Salvatore, Segal, and Lurie. We present some essential classes of calculations of factorization homology, such as for free n-disk algebras and enveloping algebras of Lie algebras, several of which have a conceptual meaning in terms of Koszul duality. Contents 1. Introduction 2 2. B-framed disks and manifolds 6 2.1. B-framings 6 2.2. Disks 9 2.3. Manifolds with boundary 11 2.4. Localizing with respect to isotopy equivalences 12 3. Homology theories for topological manifolds 14 3.1. Disk algebras 14 3.2. Factorization homology over oriented 1-manifolds with boundary 17 3.3. Homology theories 18 3.4. Pushforward 19 3.5. -
Category of Manifolds
S2- and P 2-category of manifolds J. C. G´omez-Larra~naga∗ F. Gonz´alez-Acu~nay Wolfgang Heilz Abstract n 2 2 A closed topological n-manifold M is of S - (resp. P )-category 2 if it can be covered by two open subsets W1,W2 such that the inclusions n 2 2 Wi ! M factor homotopically through maps Wi ! S (resp. P ). 2 2 We characterize all closed n-manifolds of S -category 2 and of P - category 2. 1 2 1 Introduction While studying the minimal number of critical points of a closed smooth n- manifold M n, denoted by crit(M n), Lusternik and Schnirelmann introduced what is now called the Lusternik-Schnirelmann category of M n, denoted by cat(M n), which is defined to be the the smallest number of sets, open and contractible in M n that are needed to cover M n. They showed that cat(M n) is a homotopy type invariant with values between 2 and n+1 and furthermore that cat(M n) ≤ crit(M n). This invariant has been widely studied, many references can be found in [CLOT]. ∗Centro de Investigaci´onen Matem´aticas,A.P. 402, Guanajuato 36000, Gto. M´exico and Instituto de Matem´aticas,UNAM, Ciudad Universitaria, 04510 M´exico,D.F. M´exico. [email protected] yInstituto de Matem´aticas,UNAM, 62210 Cuernavaca, Morelos, M´exicoand Cen- tro de Investigaci´on en Matem´aticas, A.P. 402, Guanajuato 36000, Gto. M´exico. fi[email protected] zDepartment of Mathematics, Florida State University, Tallahasee, FL 32306, USA. -
Higher Categorical Structures and Their Applications
PROJECT DESCRIPTION: HIGHER CATEGORICAL STRUCTURES AND THEIR APPLICATIONS PROPOSED RESEARCH 1. Background, context, and perspective Eilenberg and Mac Lane introduced categories, functors, and natural transforma- tions in their 1945 paper [54]. The language they introduced transformed modern mathematics. Their focus was not on categories and functors, but on natural trans- formations, which are maps between functors. Implicitly, they were introducing the 2-category “Cat” of categories, functors, and natural transformations. Higher category theory concerns higher level notions of naturality, which can be expressed as maps between natural transformations, maps between such maps, and so on, that is, maps between maps between maps. Just as the original definitions of Eilenberg and Mac Lane gave a way of thinking about categorical structures and analogies between such structures in different fields, higher category theory promises to allow serious thinking about and study of higher categorical struc- tures that appear in a variety of specific fields. The need for such a language has become apparent, almost simultaneously, in mathematical physics, algebraic geom- etry, computer science, logic, and, of course, category theory. As we shall explain, such a language and a relevant body of results is already implicit throughout al- gebraic topology. In all of these areas, higher categorical structures are there in nature, and one needs a coherent way of thinking about them. To give some feel for how such structures appear, we briefly consider topological quantum field theory (TQFT). A TQFT is a structure-preserving functor from a suitable cobordism category of manifolds to an analogously structured algebraic category. With the usual definitions, the objects of the domain category are closed manifolds of a certain dimension and the maps between them are equivalence classes of cobordisms between them, which are manifolds with boundary in the next higher dimension. -
Three Lectures on Topological Manifolds
THREE LECTURES ON TOPOLOGICAL MANIFOLDS ALEXANDER KUPERS Abstract. We introduce the theory of topological manifolds (of high dimension). We develop two aspects of this theory in detail: microbundle transversality and the Pontryagin- Thom theorem. Contents 1. Lecture 1: the theory of topological manifolds1 2. Intermezzo: Kister's theorem9 3. Lecture 2: microbundle transversality 14 4. Lecture 3: the Pontryagin-Thom theorem 24 References 30 These are the notes for three lectures I gave at a workshop. They are mostly based on Kirby-Siebenmann [KS77] (still the only reference for many basic results on topological manifolds), though we have eschewed PL manifolds in favor of smooth manifolds and often do not give results in their full generality. 1. Lecture 1: the theory of topological manifolds Definition 1.1. A topological manifold of dimension n is a second-countable Hausdorff space M that is locally homeomorphic to an open subset of Rn. In this first lecture, we will discuss what the \theory of topological manifolds" entails. With \theory" I mean a collection of definitions, tools and results that provide insight in a mathematical structure. For smooth manifolds of dimension ≥ 5, handle theory provides such insight. We will describe the main tools and results of this theory, and then explain how a similar theory may be obtained for topological manifolds. In an intermezzo we will give the proof of the Kister's theorem, to give a taste of the infinitary techniques particular to topological manifolds. In the second lecture we will develop one of the important tools of topological manifold theory | transversality | and in the third lecture we will obtain one of its important results | the classification of topological manifolds of dimension ≥ 6 up to bordism. -
Proquest Dissertations
u Ottawa l.'Unh'crsilc cnnnrlicnne Canada's university FACULTE DES ETUDES SUPERIEURES ISS5I FACULTY OF GRADUATE AND ET POSTOCTORALES U Ottawa POSDOCTORAL STUDIES K'Universitd canadienne Canada's university Guennadi Kondratiev TOTEWDElJTH^TAUTFOROFTFESfS" Ph.D. (Mathematics) GRADE/DEGREE Department of Mathematics and Statistics WUITETEWLIVMPA^ Duality, Manifolds, Structures TITRE DE LA THESE / TITLE OF THESIS Philip Scott TTRECTEURTDWC^ Richard Blute CO-DIRECTEUR (CO-DIRECTRICE) DE LA THESE / THESIS CO-SUPERVISOR EXAMINATEURS (EXAMINATRICES) DE LA THESE / THESIS EXAMINERS Inna Bumagin Paul-Eugene Parent Pieter Hofstra James Stasheff Gary W. Slater Le Doyen de la Faculte des etudes superieures et postdoctorales / Dean of the Faculty of Graduate and Postdoctoral Studies DUALITY, MANIFOLDS, STRUCTURES G. V. Kondratiev A Thesis submitted to the Faculty of Graduate and Postdoctoral Studies University of Ottawa in partial fulfillment of the requirements for the Ph.D. degree in the Ottawa-Carleton Institute for Graduate Studies and Research in Mathematics and Statistics © G. V. Kc ndratiev, Ottawa, Canada, 20V Library and Bibliotheque et 1*1 Archives Canada Archives Canada Published Heritage Direction du Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A0N4 Ottawa ON K1A0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-49370-0 Our file Notre reference ISBN: 978-0-494-49370-0 NOTICE: AVIS: The author has granted a non L'auteur a accorde une licence non exclusive exclusive license allowing Library -
Differential Cohomology Theories As Sheaves on Manifolds
Differential cohomology theories as sheaves on manifolds Peter J. Haine May 16, 2020 Contents 1 Sheaves on the category of manifolds 2 1.1 Checking equivalences on stalks ...................... 4 1.2 Digression: Excision & the sheaf condition ................ 5 1.3 Digression: relation to infinite dimensional manifolds .......... 8 2 퐑-invariant sheaves 9 2.1 Description of the constant sheaf functor ................. 12 2.2 Criteria for 퐑-invariance .......................... 13 3 퐑-localization 15 3.1 The Morel–Suslin–Voevodsky construction ................ 15 3.2 Proof of the Morel–Suslin–Voevodsky formula .............. 16 3.3 Simplicial homotopies in ∞-categories .................. 19 4 The Transfer Conjecture 22 4.1 Categories of spans ............................. 23 4.2 Spans and commutative monoids ..................... 25 4.3 The Transfer Conjecture after Bachmann–Hoyois ............ 26 5 Structures in the stable case 28 5.1 The fracture square ............................. 28 5.2 The differential cohomology diagram ................... 30 5.3 Differential refinements .......................... 32 A Technical details from topos theory 35 A.1 From sheaves of spaces to 퐶-valued sheaves ............... 35 A.2 Restriction to a manifold .......................... 36 A.3 Sheafification ................................ 37 A.4 Constant sheaves are 퐑-invariant ..................... 38 A.5 Background on notions of completeness for higher topoi ........ 39 A.6 Tensor products with compactly generated ∞-categories ........ 40 1 A.7 A conservative family of points ...................... 41 A.8 Sheaves on the cartesian site ........................ 43 A.9 The sheafification of an 퐑-invariant presheaf ............... 44 References 46 Overview In these notes we set up differential cohomology theories as sheaves of spectra on the category of manifolds, and prove the basic structural results that we need to work with differential cohomology theories.