# John Christian Ottem

Department of
Mathematics

University of Oslo

Box 1053, Blindern, 0316 Oslo, Norway

Email: johnco@math.uio.no

Phone: +4722855704

Office: B607

My research interests are in algebraic geometry.

**Algebraic
geometry group at UiO**
**Algebra/algebraic
geometry seminar at UiO.**
### Events

**
Geometry of Moduli**
August 7, 2017 - Aug. 11, 2017, Lofoten, Norway.

**
Polar geometry: A conference celebrating the work of Ragni Piene on the occasion of her 70th birthday.**
January 26-28, 2017, University of Oslo.

** Nordfjordeid Summer School: Stability conditions on triangulated categories and geometric applications**
June 13-17, 2016, Sophus Lie Conference Center, Nordfjordeid, Norway.

### Teaching

**MAT4230
Algebraic Geometry III** (Fall 2016).

### Publications

Effective cones of cycles on blow-ups of projective space (with
I. Coskun, J.Lesieutre). To appear in Algebra & Geometry. PDF

Nef cycles on some hyperkahler fourfolds. PDF

Curves disjoint from a nef divisor (with J. Lesieutre). To appear in
Michigan Math. J. PDF

On subvarieties with ample normal bundle. *To appear in Journal of the
European Mathematical Society * PDF

Quartic spectrahedra (with K. Ranestad, B. Sturmfels,
C. Vinzant) * Math. Prog. B* (2015). PDF

Birational geometry of hypersurfaces in products of projective
spaces. *Mathematische Zeitschrift* 280 (2015), 135-148 PDF

Ample subvarieties and *q*-ample divisors. *Advances in Mathematics* 229 (2012), 2868-2887. PDF

Algebraic boundaries of Hilbert's SOS cones (with G. Blekherman, J. Hauenstein, K. Ranestad
and B. Sturmfels). * Compositio Mathematica *148 (2012). PDF

Partially ample line bundles on toric varieties. (with N. Broomhead and
A. Prendergast-Smith). *To appear in Glasgow Math. J. (2015).* PDF

Components of the Hilbert scheme of space curves on low-degree smooth
surfaces (with J. O. Kleppe).* International Journal of Mathematics* Vol. 26, (2015) PDF

The Cox ring of a K3 surface of Picard number two.* Journal of Pure
and Applied Algebra *
217 (2013), 709-715. PDF

On the Cox Ring of P^2 Blown Up in Points on a Line. *Mathematica
Scandinavica * 9,
(2011), 21-31. PDF

### Notes

`Positivity of higher codimension cycles'. Summer school notes, Vlieland,
September 2016. PDF