Covering Spaces in Homotopy Type Theory

Covering spaces play an important role in classical homotopy theory, whose algebraic characteristics have deep connections with fundamental groups of underlying spaces. It is natural to ask whether these connections can be stated in homotopy type theory (HoTT), an exciting new framework coming with an interpretation in homotopy theory. This note summarizes the author’s attempt to recover the classical results (e.g., the classification theorem) so as to explore the expressiveness of the new foundation. Some interesting techniques employed in the current proofs seem applicable to other constructions as well.

[1]  Jeremy Avigad,et al.  The Lean Theorem Prover (System Description) , 2015, CADE.

[2]  P. Martin-Löf An Intuitionistic Theory of Types: Predicative Part , 1975 .

[3]  S. Awodey,et al.  Homotopy theoretic models of identity types , 2007, Mathematical Proceedings of the Cambridge Philosophical Society.

[4]  Daniel R. Licata,et al.  π n (S n ) in Homotopy Type Theory , 2013, CPP.

[5]  Benno van den Berg,et al.  Types are weak ω‐groupoids , 2008, 0812.0298.

[6]  U. Norell,et al.  Towards a practical programming language based on dependent type theory , 2007 .

[7]  J. Y. Girard,et al.  Interpretation fonctionelle et elimination des coupures dans l'aritmetique d'ordre superieur , 1972 .

[8]  Peter LeFanu Lumsdaine,et al.  The simplicial model of Univalent Foundations (after Voevodsky) , 2012, Journal of the European Mathematical Society.

[9]  Guillaume Brunerie,et al.  On the homotopy groups of spheres in homotopy type theory , 2016, ArXiv.

[10]  Antonius J. C. Hurkens A Simplification of Girard's Paradox , 1995, TLCA.

[11]  Thierry Coquand,et al.  Generalizations of Hedberg's Theorem , 2013, TLCA.

[12]  Eric Finster,et al.  A generalized Blakers–Massey theorem , 2017, Journal of Topology.

[13]  Thierry Coquand,et al.  Notions of Anonymous Existence in Martin-Löf Type Theory , 2016, Log. Methods Comput. Sci..

[14]  Peter LeFanu Lumsdaine,et al.  A Mechanization of the Blakers–Massey Connectivity Theorem in Homotopy Type Theory , 2016, 2016 31st Annual ACM/IEEE Symposium on Logic in Computer Science (LICS).

[15]  Daniel R. Licata,et al.  Calculating the Fundamental Group of the Circle in Homotopy Type Theory , 2013, 2013 28th Annual ACM/IEEE Symposium on Logic in Computer Science.

[16]  Michael Shulman,et al.  The Seifert-van Kampen Theorem in Homotopy Type Theory , 2016, CSL.

[17]  Peter LeFanu Lumsdaine Weak omega-Categories from Intensional Type Theory , 2009, TLCA.

[18]  E. M. Rijke,et al.  Homotopy type theory , 2012 .

[19]  Robert Graham,et al.  Synthetic Homology in Homotopy Type Theory , 2017, ArXiv.

[20]  Daniel R. Licata,et al.  Eilenberg-MacLane spaces in homotopy type theory , 2014, CSL-LICS.

[21]  P. Lumsdaine WEAK ω-CATEGORIES FROM INTENSIONAL TYPE THEORY , 2008 .

[22]  R. Ho Algebraic Topology , 2022 .

[23]  Kuen-Bang Hou Homotopy Theory and Univalent Foundations Covering Spaces in Homotopy Type Theory , 2014 .

[24]  Ulrik Buchholtz,et al.  Homotopy Type Theory in Lean , 2017, ITP.

[25]  Richard Garner,et al.  The identity type weak factorisation system , 2008, Theor. Comput. Sci..

[26]  Richard Garner,et al.  Topological and Simplicial Models of Identity Types , 2012, TOCL.

[27]  M. Warren Homotopy Theoretic Aspects of Constructive Type Theory , 2008 .

[28]  Daniel R. Licata,et al.  A Cubical Approach to Synthetic Homotopy Theory , 2015, 2015 30th Annual ACM/IEEE Symposium on Logic in Computer Science.

[29]  P. Lumsdaine,et al.  THE SIMPLICIAL MODEL OF UNIVALENT FOUNDATIONS , 2014 .