2026-09-18T19:49:11Zhttps://dspace.mit.edu/server/oai/requestoai:dspace.mit.edu:1721.1/901872026-06-16T18:55:17Zcom_1721.1_7582com_1721.1_7581col_1721.1_131022
James McKernan.
Lesieutre, John
Massachusetts Institute of Technology. Department of Mathematics.
Massachusetts Institute of Technology. Department of Mathematics
2014-09-19T21:44:55Z
2014-09-19T21:44:55Z
2014
2014
http://hdl.handle.net/1721.1/90187
890211399
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mathematics, 2014.
47
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 61-64).
We construct counterexamples to a number of questions related to positivity properties of line bundles on algebraic varieties. The examples are based on studying the geometry of varieties that admit pseudo automorphisms of positive entropy, and in particular on the action of standard Cremona transformations on blow-ups of projective space at configurations of points. The main examples include the following: nefness is not an open condition in families; the diminished base locus of a divisor is not always a closed set; Zariski decompositions do not necessarily exist in dimension three; asymptotic multiplicity invariants are not always finite in the relative setting; and the number of Fourier- Mukai partners of a variety can be infinite.
by John Lesieutre.
Ph.D.
64 pages
eng
Massachusetts Institute of Technology
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
http://dspace.mit.edu/handle/1721.1/7582
Mathematics.
Negative answers to some positivity questions
Thesis
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