Articles (2001-2022)

On models of algebraic group actions,
Proceedings of the Indian Academy of Sciences (Mathematical Sciences).
Special Issue in Memory of Prof. C. S. Seshadri 132 (2022), 1-17.

Automorphism groups of almost homogeneous varieties,
Facets of algebraic geometry. A collection in honor of William Fulton's 80th birthday. Volume 1.
London Mathematical. Society Lecture Note Series 472, 54-76, Cambridge University Press, 2022.

Homomorphisms of algebraic groups: representability and rigidity,
Michigan Mathematical Journal (special volume in honor of Gopal Prasad) 72 (2022), 51-76.

(avec S. Senthamarai Kannan) Minimal rational curves on generalized Bott-Samelson varieties,
Compositio Mathematica 157 (2021), 122-153.

Some automorphism groups are linear algebraic,
Moscow Mathematical Journal 21 (2021), 453-466.

Homogeneous varieties under split solvable algebraic groups,
Indagationes Mathematicae (special issue to the memory of T. A. Springer) 32 (2021), 1139-1151.

On the fundamental groups of commutative algebraic groups,
Annales Henri Lebesgue 3 (2020), 1-34.

Homogeneous vector bundles over abelian varieties via representation theory,
Representation Theory 24 (2020), 85-114.

Very special algebraic groups (avec E. Peyre),
Comptes Rendus Mathématique 6 (2020), 713-719.

Homological dimension of isogeny categories of commutative algebraic groups,
European Journal of Mathematics 5 (2019), 1107-1138.

Commutative algebraic groups up to isogeny. II,
Contemp. Math. 705 (2018), 1-36.

Log Kodaira dimension of homogeneous varieties (avec De-Qi Zhang),
Adv. Stud. Pure Math. 75 (2017), 1-6.

Commutative algebraic groups up to isogeny,
Documenta Math. 22 (2017), 679-725.

Epimorphic subgroups of algebraic groups,
Math. Res. Letters. 24 (2017), 1649-1665.

Algebraic group actions on normal varieties,
Trans. Moscow Math. Soc. 78 (2017), 85-107.

Some structure theorems for algebraic groups,
Proc. Symp. Pure Math. 94 (2017), 53-125.

Symplectic resolutions for conical symplectic varieties
(avec B. Fu), Internat. Math. Res. Notices 12 (2015), 4335-4343.

On linearization of line bundles,
J. Math. Sci. Univ. Tokyo (Kodaira Centennial Issue) 22 (2015), 1-35.

Minimal rational curves on wonderful group compactifications
(avec B. Fu), J. Éc. polytech. Math. 2 (2015), 153-170.

On extensions of algebraic groups with finite quotient,
Pacific J. Math. (Robert Steinberg Memorial Issue) 279 (2015), 135-153.

Which algebraic groups are Picard varieties?
Science China Mathematics 58 (2014), 461-478.

On algebraic semigroups and monoids,
Algebraic Monoids, Group Embeddings, and Algebraic Combinatorics,
Fields Institute Communications 71, 1-54, Springer, 2014.

Algebraic semigroups are strongly π-regular
(avec L. E. Renner),
Algebraic Monoids, Group Embeddings, and Algebraic Combinatorics,
Fields Institute Communications 71, 55-59, Springer, 2014.

On algebraic semigroups and monoids, II,
Semigroup Forum 88 (2014), 250-272.

On automorphisms and endomorphisms of projective varieties,
Automorphisms in Birational and Affine Geometry,
Springer Proc. Math. Stat. 79, 59-82, Springer, 2014.

Homogeneous projective bundles over abelian varieties,
Algebra Number Theory 7 (2013), 2475-2510.

On connected automorphism groups of algebraic varieties,
J. Ramanujan Math. Soc. 28A (Special Issue - 2013), 41-54.

The coherent cohomology ring of an algebraic group,
Algebr. Represent. Theory 16 (2013), 1449-1467.

Prime-to-p étale covers of algebraic groups,
(avec T. Szamuely), Bull. London Math. Soc. 45 (2013), 602-612.

Notions of purity and the cohomology of quiver moduli,
(avec R. Joshua), Internat. J. Math. 23 (2012), no. 9.

Homogeneous bundles over abelian varieties,
J. Ramanujan Math. Soc. 27 (2012), 91-118.

On automorphism groups of fiber bundles,
Publ. Math. Urug. 12 (2011), 39-66.

On the geometry of algebraic groups and homogeneous spaces,
J. Algebra 329 (2011), 52-71.

Counting points of homogeneous varieties over finite fields
(avec E. Peyre)
J. Reine Angew. Math. 645 (2010), 105-124.

Some basic results on actions of non-affine algebraic groups
Symmetry and Spaces: in honor of Gerry Schwarz,
Progr. Math. 278, 1-20, Birkäuser (2010).

Vanishing theorems for Dolbeault cohomology of log homogeneous varieties
Tohoku Math. J. 61 (2009), 365-392.

Anti-affine algebraic groups
J. Algebra 321 (2009), 934-952.

Local structure of algebraic monoids
Mosc. Math. J. 8 (2008), 1-21.

Equivariant Chow ring and Chern classes of wonderful symmetric varieties of minimal rank
(avec R. Joshua)
Transform. Groups (special volume in honor of B. Kostant) 13 (2008), 471-493.

Log homogeneous varieties
dans : Actas del XVI Coloquio Latinoamericano de Àlgebra, 1-39,
Revista Matemática Iberoamericana, Madrid, 2007.

The structure of normal algebraic monoids
(avec A. Rittatore)
Semigroup Forum 74 (2007), 410-422.

Construction of equivariant vector bundles
dans : Algebraic groups and homogeneous spaces, 83-111, Narosa, New Dehli, 2007.

The total coordinate ring of a spherical variety
J. Algebra (special volume in honor of E.B. Vinberg) 313 (2007), 61-99.

Stable spherical varieties and their moduli
(avec V. Alexeev)
Int. Math. Res. Pap. IMRP 16 (2006), 1-57.

F-regularity of large Schubert varieties
(avec J. F. Thomsen)
Amer. J. Math. 128 (2006), 949-962.

Vanishing of top equivariant Chern classes of regular embeddings
(avec I. Kausz)
Asian J. Math. 9 (2005), 489-496.

Moduli of affine schemes with reductive group action
(avec V. Alexeev)
J. Algebraic Geom. 14 (2005), 83-117.

The equivariant cohomology ring of regular varieties
(avec J. B. Carrell)
Michigan Math. J. 52 (2004), 189-203.

Intersection cohomology of reductive varieties
(avec R. Joshua)
J. Eur. Math. Soc. 6 (2004), 465-481.

Toric degenerations of spherical varieties
(avec V. Alexeev)
Selecta Math. (N.S.) 10 (2004), 453-478.

Stable reductive varieties II: Projective case
(avec V. Alexeev)
Adv. Math. 184 (2004), 380-408.

Stable reductive varieties I: Affine varieties
(avec V. Alexeev)
Invent. Math. 157 (2004), 227-274.

A geometric approach to standard monomial theory
(avec V. Lakshmibai)
Represent. Theory 7 (2003), 651-680.

The cone of effective one-cycles of certain G-varieties
dans : A Tribute to C. S. Seshadri, 180-198, Hindustan Book Agency, 2003.

Multiplicity-free subvarieties of flag varieties
dans : Contemporary Math. 331, 13-23, Amer. Math. Soc., Providence, 2003.

Group completions via Hilbert schemes
J. Algebraic Geom. 12 (2003), 605-626.

Positivity in the Grothendieck group of complex flag varieties
J. Algebra (special volume in honor of Claudio Procesi) 258 (2002), 137-159.

The virtual Poincaré polynomials of homogeneous spaces
(avec E. Peyre)
Compos. Math. 134 (2002), 319-335.

On orbit closures of spherical subgroups in flag varieties
Comment. Math. Helv. 76 (2001), 263-299.