?
Automorphisms of Weighted Complete Intersections
Proceedings of the Steklov Institute of Mathematics. 2019. Vol. 307. P. 198-209.
We show that smooth well-formed weighted complete intersections have finite automorphism groups, with several obvious exceptions.
Publication based on the results of:
Shramov K., Przyjalkowski V., / Cornell University. Series arXiv "math". 2020.
We show that every reductive subgroup of the automorphism group of a quasi-smooth well formed weighted complete intersection is a restriction of a subgroup in the automorphism group in the ambient weighted projective space. Also, we provide examples demonstrating that an automorphism group of a quasi-smooth well formed Fano weighted complete intersection may be infinite ...
Added: August 19, 2020
Prokhorov Y., Shramov K., ASIAN JOURNAL OF MATHEMATICS 2020 Vol. 24 No. 2 P. 355-368
We prove that automorphism groups of Inoue and primary Kodaira surfaces are Jordan. ...
Added: November 5, 2020
Vladimir L. Popov, Springer Proceedings in Mathematics & Statistics 2014 Vol. 79 P. 185-213
This is an expanded version of my talk at the workshop
``Groups of Automorphisms in Birational and Affine Geometry'',
October 29–November 3, 2012, Levico Terme, Italy.
The first section is focused on Jordan groups in abstract setting,
the second on that in the settings of automorphisms groups and
groups of birational self-maps of algebraic varieties.
The appendix is an expanded version ...
Added: April 28, 2014
Popov V. L., Zarhin Y., / Cornell University. Series math "arxiv.org". 2018. No. 1808.01136.
We classify the types of root systems $R$ in the rings of integers of number fields $K$ such that the Weyl group $W(R)$ lies in the group $\mathcal L(K)$ generated by ${\rm Aut} (K)$ and multipli\-ca\-tions by the elements of $K^*$. We also classify the Weyl groups of roots systems of rank $n$ which are ...
Added: August 8, 2018
Tokyo : American Mathematical Society, World Scientific, 2017
Preface
The workshop “Algebraic Varieties and Automorphism Groups” was held at the Research Institute of Mathematical Sciences (RIMS), Kyoto University during July 7-11, 2014. There were over eighty participants including twenty people from overseas Canada, France, Germany, India, Korea, Poland, Russia, Singapore, Switzerland, and USA.
Recently, there have been remarkable developments in algebraic geometry and related fields, ...
Added: July 12, 2017
Vladimir L. Popov, / Cornell University. Series math "arxiv.org". 2021. No. 2106.02072.
For each integer n>0, we construct a series of irreducible algebraic varieties X, for which the automorphism group Aut(X) contains as a subgroup the automorphism group Aut(F_n) of a free group F_n of rank n. For n > 1, such groups Aut(X) are nonamenable, and for n > 2, they are nonlinear and contain the ...
Added: June 7, 2021
Vikulova A., / Cornell University. Series arXiv "math". 2022.
In this paper we prove that for n-dimensional smooth l-Fano well formed weighted complete intersections, which is not isomorphic to a usual projective space, the upper bound for l is equal to ⌈log2(n+2)⌉−1. We also prove that the only l-Fano of dimension n among such manifolds with inequalities ⌈log3(n+2)⌉⩽l⩽⌈log2(n+2)⌉−1 is a complete intersection of quadrics in a usual projective space. ...
Added: November 27, 2022
Avilov A., Sbornik Mathematics 2016 Vol. 307 No. 3 P. 315-330
We prove that any G-del Pezzo threefold of degree 4, except for a one-parameter family and four distinguished cases, can be equivariantly reconstructed to the projective space ℙ3, a quadric Q ⊂ ℙ4 , a G-conic bundle or a del Pezzo fibration. We also show that one of these four distinguished varieties is birationally rigid ...
Added: July 6, 2016
Nikolay Konovalov, / Cornell University. Series "Working papers by Cornell University". 2022. No. 2202.07507.
Let $V_{n,d}$ be the variety of equations for hypersurfaces of degree $d$ in $\mathbb{P}^n(\mathbb{C})$ with singularities not worse than simple nodes. We prove that the orbit map $G'=SL_{n+1}(\mathbb{C}) \to V_{n,d}$, $g\mapsto g\cdot s_0$, $s_0\in V_{n,d}$ is surjective on the rational cohomology if $n>1$, $d\geq 3$, and $(n,d)\neq (2,3)$. As a result, the Leray-Serre spectral sequence ...
Added: September 12, 2022
Przyjalkowski V., Shramov K., Communications in Number Theory and Physics 2020 Vol. 14 No. 3 P. 511-553
We prove that if a smooth variety with non-positive canonical class can be embedded into a weighted projective space of dimension n as a well formed complete intersection and it is not an intersection with a linear cone therein, then the weights of the weighted projective space do not exceed n+1. Based on this bound ...
Added: October 13, 2020
Ovcharenko M., / Cornell University. Series math "arxiv.org". 2020.
We study smooth Fano weighted complete intersections with respect to the new invariant -- the variance var(X) = coindex(X) - codim(X). ...
Added: June 12, 2020
Sheina K., / Cornell University. Series arXiv "math". 2020. No. 04348v1.
The basic automorphism group of a Cartan foliation (M, F) is the quotient group of the automorphism group of (M, F) by the normal subgroup, which preserves every leaf invariant. For Cartan foliations covered by fibrations, we find sufficient conditions for the existence of a structure of a finite-dimensional Lie group in their basic automorphism groups. Estimates ...
Added: December 9, 2020
Shramov K., European Journal of Mathematics 2019
We show that automorphism groups of Hopf and Kodaira surfaces have unbounded
finite subgroups. For elliptic fibrations on Hopf, Kodaira, bielliptic, and K3 surfaces,
we make some observations on finite groups acting along the fibers and on the base
of such a fibration. ...
Added: December 11, 2019
Shramov K., Przyjalkowski V., / Cornell University. Series arXiv "math". 2019.
We classify smooth Fano weighted complete intersections of large codimension. ...
Added: November 19, 2019
Avilov A., Математические заметки 2020 Т. 107 № 1 С. 3-10
The forms of the Segre cubic over non-algebraically closed fields, their automorphisms groups, and equivariant birational rigidity are studied. In particular, it is shown that all forms of the Segre cubic over any field have a point and are cubic hypersurfaces. ...
Added: May 11, 2020
Prokhorov Y., Cheltsov I., / Cornell University. Series arXiv "math". 2020.
We classify del Pezzo surfaces with Du Val singularities that have infinite automorphism groups, and describe the connected components of their automorphisms groups. ...
Added: August 19, 2020
Vladimir L. Popov, / Cornell University. Series math "arxiv.org". 2014. No. 1401.0278.
We explore orbits, rational invariant functions, and quotients of the natural actions of connected, not necessarily finite dimensional subgroups of the automorphism groups of irreducible algebraic varieties. The applications of the results obtained are given. ...
Added: January 3, 2014
Kuyumzhiyan K., Proceedings of the American Mathematical Society 2020 No. 148 P. 3723-3731
We prove the conjecture of Berest-Eshmatov-Eshmatov by showing that the group of automorphisms of a product of Calogero-Moser spaces C_n_i, where the n_i are pairwise distinct, acts m-transitively for each m. ...
Added: August 18, 2020
Nina I. Zhukova, Anna Yu. Dolgonosova .., Central European Journal of Mathematics 2013 Vol. 11 No. 12 P. 2076-2088
The category of foliations is considered. In this category
morphisms are differentiable mappings transforming leaves of one
foliation into leaves of the other foliation.
We proved that the automorphism group of the foliations
admitting a transverse linear connection is an infinite-dimensional
Lie group modeled on $LF$-spaces. This result extends the corresponding
result of Macias-Virgos and Sanmartin for Riemannian foliations.
In particular, our ...
Added: September 28, 2014
Prokhorov Y., Shramov K., / Cornell University. Series arXiv "math". 2018.
We prove that automorphism groups of Inoue and primary Kodaira surfaces are Jordan. ...
Added: June 8, 2019
Vladimir L. Popov, / Cornell University. Series math "arxiv.org". 2013. No. 1307.5522.
This is an expanded version of my talk at the workshop ``Groups of Automorphisms in Birational and Affine Geometry'', October 29–November 3, 2012, Levico Terme, Italy. The first section is focused on Jordan groups in abstract setting, the second on that in the settings of automorphisms groups and groups of birational self-maps of algebraic varieties. ...
Added: July 21, 2013
Vladimir L. Popov, Transformation Groups 2014 Vol. 19 No. 2 P. 549-568
We explore orbits, rational invariant functions, and quotients of the natural actions of connected, not necessarily finite dimensional subgroups of the automorphism groups of irreducible algebraic varieties. The applications of the results obtained are given. ...
Added: March 17, 2014
Zhukova N., Moscow Mathematical Journal 2018
We introduce a category of rigid geometries on singular spaces which
are leaf spaces of foliations and are considered as leaf manifolds. We
single out a special category F_0 of leaf manifolds containing the orbifold
category as a full subcategory. Objects of F_0 may have non-Hausdorff
topology unlike the orbifolds. The topology of some objects of F_0 does
not satisfy ...
Added: April 2, 2018
Shramov K., Prokhorov Y., / Cornell University. Series arXiv "math". 2019.
We classify compact complex surfaces whose groups of bimeromorphic selfmaps have bounded finite subgroups. We also prove that the stabilizer of a point in the automorphism group of a compact complex surface of zero Kodaira dimension, as well as the stabilizer of a point in the automorphism group of an arbitrary compact Kaehler manifold of ...
Added: November 19, 2019