John Christian Ottem

Associate Professor - Algebra, Geometry and Topology
Image of John Christian Ottem
Norwegian version of this page
Phone +47-22855930
Username
Visiting address Moltke Moes vei 35 Niels Henrik Abels hus 0851 OSLO
Postal address Postboks 1053 Blindern 0316 OSLO

Research interests

Higher dimensional algebraic geometry, positivity of line bundles and subschemes, Calabi-Yau manifolds, and the moduli space of curves.

Courses

Background

  • Junior Research Fellow, King's College 2013-2015
  • Post doctoral research associate, DPMMS, University of Cambridge 2013-2015
  • Ph.D. University of Cambridge 2013

Awards

  • 'Unge forskertalenter'. Research Council of Norway 2016-2021.
Tags: Algebra and algebraic geometry

Publications

  • Ottem, John Christian & Benoist, Olivier (2018). Failure of the integral Hodge conjecture for threefolds of Kodaira dimension zero. arXiv.org.  ISSN 2331-8422.
  • Ottem, John Christian & Gounelas, Frank (2018). Remarks on the positivity of the cotangent bundle of a K3 surface. arXiv.org.  ISSN 2331-8422.
  • Ottem, John Christian & Lehmann, Brian (2018). Positivity of the diagonal. Advances in Mathematics.  ISSN 0001-8708.  335, s 665- 695 . doi: 10.1016/j.aim.2018.07.002 Full text in Research Archive. Show summary
  • Ottem, John Christian & Mongardi, Giovanni (2018). Curve classes on irreducible holomorphic symplectic varieties. arXiv.org.  ISSN 2331-8422.
  • Ottem, John Christian & Rennemo, Jørgen Vold (2018). A counterexample to the birational Torelli problem for Calabi-Yau 3-folds. Journal of the London Mathematical Society.  ISSN 0024-6107.  97(3), s 427- 440 . doi: 10.1112/jlms.12111 Full text in Research Archive. Show summary
  • Ottem, John Christian (2017). Nef cycles on some hyperkahler fourfolds. arXiv.org.  ISSN 2331-8422. Full text in Research Archive. Show summary
  • Coskun, Izzet; Lesieutre, John & Ottem, John Christian (2016). Effective cones of cycles on blowups of projective space. Algebra & Number Theory.  ISSN 1937-0652.  10(9), s 1983- 2014 . doi: 10.2140/ant.2016.10.1983 Show summary
  • Lesieutre, John & Ottem, John Christian (2016). Curves disjoint from a nef divisor. The Michigan mathematical journal.  ISSN 0026-2285.  65(2), s 321- 332 . doi: 10.1307/mmj/1465329015 Show summary
  • Ottem, John Christian (2016). On subvarieties with ample normal bundle. Journal of the European Mathematical Society (Print).  ISSN 1435-9855.  18(11), s 2459- 2468 . doi: 10.4171/JEMS/644 Full text in Research Archive. Show summary
  • Ottem, John Christian; Prendergast-Smith, Artie & Broomhead, Nathan (2016). Partially ample line bundles on toric varieties. Glasgow Mathematical Journal.  ISSN 0017-0895.  58(3), s 587- 598 . doi: 10.1017/S001708951500035X Show summary
  • Kleppe, Jan Oddvar & Ottem, John Christian (2015). Components of the Hilbert scheme of space curves on low-degree smooth surfaces. International Journal of Mathematics.  ISSN 0129-167X.  26(2) . doi: 10.1142/S0129167X15500172 Full text in Research Archive. Show summary
  • Ottem, John Christian (2015). Birational geometry of hypersurfaces in products of projective spaces. Mathematische Zeitschrift.  ISSN 0025-5874.  280(1), s 135- 148 . doi: 10.1007/s00209-015-1415-x
  • Ottem, John Christian (2013). Cox rings of K3 surfaces with Picard number 2. Journal of Pure and Applied Algebra.  ISSN 0022-4049.  217(4), s 709- 715 . doi: 10.1016/j.jpaa.2012.09.016 Full text in Research Archive.
  • Blekherman, Grigoriy; Hauenstein, Jonathan; Ottem, John Christian; Ranestad, Kristian & Sturmfels, Bernd (2012). Algebraic boundaries of Hilbert's SOS cones. Compositio Mathematica.  ISSN 0010-437X.  148(6), s 1717- 1735 . doi: 10.1112/S0010437X12000437 Full text in Research Archive.
  • Ottem, John Christian (2012). Ample subvarieties and q-ample divisors. Advances in Mathematics.  ISSN 0001-8708.  229(5), s 2868- 2887 . doi: 10.1016/j.aim.2012.02.001
  • Ottem, John Christian (2011). ON THE COX RING OF P-2 BLOWN UP IN POINTS ON A LINE. Mathematica Scandinavica.  ISSN 0025-5521.  109(1), s 22- 30 Full text in Research Archive. Show summary

View all works in Cristin

  • Ottem, John Christian (2018). Integral Hodge conjecture for threefolds.
  • Ottem, John Christian (2018). Integral Hodge conjecture for threefolds.
  • Ottem, John Christian (2018). Integral hodge conjecture for holomorphic symplectic varieties.
  • Ottem, John Christian (2018). Positivity of the higher codimension cycles.
  • Ottem, John Christian (2018). The birational Torelli problem for Calabi-Yau 3-folds.
  • Ottem, John Christian (2018). The integral Hodge conjecture for threefolds.
  • Ottem, John Christian (2017). A counterexample to the birational Torelli problem for Calabi Yau threefolds.
  • Ottem, John Christian (2017). A counterexample to the birational Torelli problem for Calabi-Yau threefolds.
  • Ottem, John Christian (2017). Nef cycles of higher codimension.
  • Ottem, John Christian (2017). Nef cycles on some hyperkahler fourfolds.
  • Ottem, John Christian (2017). Nef cycles on some hyperkahler fourfolds.
  • Ottem, John Christian (2017). Nef cycles on some hyperkahler manifolds.
  • Ottem, John Christian (2017). Nef cycles on some hyperkahler manifolds.
  • Ottem, John Christian (2017). Positivity of the diagonal.
  • Ottem, John Christian (2017). Positivity of the diagonal.
  • Ottem, John Christian (2017). Positivity of the diagonal.
  • Ottem, John Christian (2017). Semiample line bundles in positive characteristic.
  • Ottem, John Christian (2017). The Birational Torelli problem for Calabi-Yau 3-folds.
  • Ottem, John Christian (2016). Effective and nef cycles in higher codimension.
  • Ottem, John Christian (2016). Effective cones of cycles on blow-ups of projective space.
  • Ottem, John Christian (2016). Effective cones of cycles on blow-ups of projective space.
  • Ottem, John Christian (2016). Effective cycles of higher codimension.
  • Ottem, John Christian (2016). Effective cycles on blow-ups of projective space.
  • Ottem, John Christian (2016). Higher codimension cycles.
  • Ottem, John Christian (2016). K3 surfaces.
  • Ottem, John Christian (2016). Moduli of K3s via Global Torelli.
  • Ottem, John Christian (2016). Nef cycles on hyperkahler manifolds.
  • Ottem, John Christian (2016). Positivity in higher codimension.
  • Kleppe, Jan Oddvar & Ottem, John Christian (2012). Components of the Hilbert scheme of space curves on low-degree smooth surfaces. Show summary

View all works in Cristin

Published Jan. 6, 2016 9:05 AM - Last modified Dec. 15, 2017 12:20 AM

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