"Non UBC"@en .
"DSpace"@en .
"Florence, Mathieu"@en .
"2019-03-17T02:01:20Z"@en .
"2018-09-17T11:06"@en .
"Let $p$ be a prime number, and let $S$ be a scheme of characteristic $p>0$.\n\nFor any integer $n>1$, one can build the scheme of Witt vectors of length $n$ of $S$, denoted by $W_n(S)$. It is a natural thickening of characteristic $p^n$ of $S$.\n\nLet us say \"$W_n$-bundle\" (or Witt vector bundle if $n$ is understood) for \"vector bundle over $W_n(S)$\".\n\nIn this talk, we consider the following Question.\n\nLet $V$ be a vector bundle over $S$.\n\n$Q(n,V)$: Does $V$ extend to a $W_n$-bundle\n\nI will first give precise (hopefully elementary) definitions, and basic properties of Witt vector bundles. I will then show that the answer to question $Q$ is positive,\n\nwhen $V$ is the tautological vector bundle of the projective space of a vector bundle, defined over an affine base. I will discuss counterexamples in the general setting -- in a Galois-theoretic way.\n\nIf time permits, I plan to discuss the main motivation for raising question $Q$: lifting Galois representations.\n\nThis is joint work, with Charles De Clercq and Giancarlo Lucchini Arteche."@en .
"https://circle.library.ubc.ca/rest/handle/2429/68819?expand=metadata"@en .
"45.0"@en .
"video/mp4"@en .
""@en .
"Author affiliation: Universit\u00E9 Paris 6"@en .
"Banff (Alta.)"@en .
"10.14288/1.0377006"@en .
"eng"@en .
"Unreviewed"@en .
"Vancouver : University of British Columbia Library"@en .
"Banff International Research Station for Mathematical Innovation and Discovery"@en .
"Attribution-NonCommercial-NoDerivatives 4.0 International"@en .
"http://creativecommons.org/licenses/by-nc-nd/4.0/"@en .
"Faculty"@en .
"BIRS Workshop Lecture Videos (Banff, Alta)"@en .
"Mathematics"@en .
"Algebraic geometry"@en .
"Group theory and generalizations"@en .
"Lifting Witt vector bundles"@en .
"Moving Image"@en .
"http://hdl.handle.net/2429/68819"@en .