83 citations · 180 across the 24 of their papers we have counts for
25 papers · 1 filter
Unirationality of instanton moduli space for small charges
Dimitri Markushevich, Alexander Tikhomirov
The unirationality of the moduli space of mathematical instantons on the projective 3-space is proved for charges less than or equal to 7.
Moduli of rank two semistable sheaves on rational Fano threefolds of the main series
Alexander S. Tikhomirov, Danil A. Vassiliev
In this paper we investigate the moduli spaces of semistable coherent sheaves of rank two on the projective space and the following rational Fano manifolds of the ma…
An algebraic-geometric construction of ind-varieties of generalized flags
A. Tikhomirov, I. Penkov
We define the class of admissible linear embeddings of flag varieties. The definition is given in the general language of algebraic geometry. We then prove that an admissible linea…
Irreducible components of the moduli space of rank 2 sheaves of odd determinant on the projective space
Charles Almeida, Marcos Jardim, Alexander S. Tikhomirov
We describe new irreducible components of the moduli space of rank semistable torsion free sheaves on the three-dimensional projective space whose generic point corresponds to…
Construction of stable rank 2 vector bundles on via symplectic bundles
Alexander Tikhomirov, Sergey Tikhomirov, Danil Vasiliev
In this article we study the Gieseker-Maruyama moduli spaces of stable rank 2 algebraic vector bundles with Chern classes on the p…
Semistable rank 2 sheaves with singularities of mixed dimension on
Alexey N. Ivanov, Alexander S. Tikhomirov
We describe new irreducible components of the Gieseker-Maruyama moduli scheme of semistable rank 2 coherent sheaves with Chern classes on $…
Series of rational moduli components of stable rank 2 vector bundles on
Alexey Kytmanov, Alexander Tikhomirov, Sergey Tikhomirov
We study the problem of rationality of an infinite series of components, the so-called Ein components, of the Gieseker-Maruyama moduli space of rank 2 stable vector bundle…
Moduli spaces of rank 2 instanton sheaves on the projective space
Marcos Jardim, Mario Maican, Alexander S. Tikhomirov
We study the irreducible components of the moduli space of instanton sheaves on , that is rank 2 torsion free sheaves with satisfying $h^1(E(-2)…
New moduli components of rank 2 bundles on projective space
Charles Almeida, Marcos Jardim, Alexander Tikhomirov +1
We present a new family of monads whose cohomology is a stable rank two vector bundle on . We also study the irreducibility and smoothness together with a geometrical…
Two infinite series of moduli spaces of rank 2 sheaves on
Marcos Jardim, Dimitri Markushevich, Alexander S. Tikhomirov
We describe new components of the Gieseker--Maruyama moduli scheme of semistable rank 2 sheaves on with , and wh…
New divisors in the boundary of the instanton moduli space
Marcos Jardim, Dimitri Markushevich, Alexander S. Tikhomirov
Let denote the moduli space of rank instanton bundles of charge on . We know from several authors that is an irreducible,…
Symplectic instanton bundles on P3 and 't Hooft instantons
Ugo Bruzzo, Dimitri Markushevich, Alexander Tikhomirov
We study the moduli space of rank- symplectic instanton vector bundles on with and second Chern class .…
On the Barth-Van de Ven-Tyurin-Sato theorem
Ivan Penkov, Alexander S. Tikhomirov
The Barth-Van de Ven-Tyurin-Sato Theorem claims that any finite rank vector bundle on the infinite complex projective space is isomorphic to a direct sum of lin…
Linear ind-Grassmannians
Ivan Penkov, Alexander S. Tikhomirov
We consider ind-varieties obtained as direct limits of chains of embeddings $X_1\stackrel{ϕ_1}{\hookrightarrow}\dots\stackrel{ϕ_{m-1}}{\hookrightarrow} X_m\stackrel{ϕ_m}{\hookright…
Bubble tree compactification of moduli spaces of vector bundles on surfaces
D. Markushevich, A. S. Tikhomirov, G. Trautmann
In this article we announce some results on compactifying moduli spaces of rank-2 vector bundles on surfaces by spaces of vector bundles on trees of surfaces. This is thought as an…
Moduli of symplectic instanton vector bundles of higher rank on projective space
Ugo Bruzzo, D. Markushevich, A. S. Tikhomirov
Symplectic instanton vector bundles on the projective space constitute a natural generalization of mathematical instantons of rank 2. We study the moduli space $I_{n…
Algebraic cycles on quadric sections of cubics in P^4 under the action of symplectomorphisms
V. Guletskii, A. Tikhomirov
We consider the involution changing the sign of two coordinates in 4-dimensional projective space. The intersection S of invariant cubic and quadric hypersurfaces in P^4 is a K3-su…
Rationality of instanton moduli
D. Markushevich, A. S. Tikhomirov
Tikhomirov (2009) proved the irreducibility of the moduli space of mathematical instantons on the projective 3-space for all odd charges. The irreducibility for charges between 1 a…
Uhlenbeck-Donaldson compactification for framed sheaves on projective surfaces
Ugo Bruzzo, Dimitri Markushevich, Alexander Tikhomirov
We construct a compactification of the Uhlenbeck-Donaldson type for the moduli space of slope stable framed bundles. This is a kind of a moduli space of slope semistable…
Rank 2 vector bundles on ind-Grassmannians
Ivan Penkov, Alexander S. Tikhomirov
The simplest example of an ind-Grassmannian is the infinite projective space . The Barth-Van de Ven-Tyurin (BVT) Theorem, proved more than 30 years ago \cite{BV},…
Triviality of vector bundles on sufficiently twisted ind-Grassmannians
Ivan Penkov, Alexander S. Tikhomirov
Twisted ind-Grassmannians are ind-varieties $\GG$ obtained as direct limits of Grassmannians , for $m\in\ZZ_{>0}$, under embeddings $ϕ_m:G(r_m,V^{r_m})\to G(r_{m+1}…
A parametrization of the theta divisor of the quartic double solid
D. Markushevich, A. S. Tikhomirov
Let M(2;0,3) be the moduli space of rank-2 stable vector bundles with Chern classes c_1=0, c_2=3 on the Fano threefold X, the double solid of index two. We prove that the vector bu…
Irreducibility and Smoothness of the moduli space of mathematical 5--instantons over
I. Coanda, A. Tikhomirov, G. Trautmann
We prove that the space of mathematical instantons with second Chern class 5 over is smooth and irreducible. Unified and simple proofs for the same statements in ca…
Symplectic structure on a moduli space of sheaves on the cubic fourfold
D. Markushevich, A. S. Tikhomirov
A 10-dimensional symplectic moduli space of torsion sheaves on the cubic 4-fold is constructed. It parametrizes the stable rank 2 vector bundles on the hypeplane sections of the cu…