June huh received support from nsf grant dms1638352 and the ellentuck. Zerocycles on smooth complex projective varieties and global holomorphic forms 5 3. In this paper, we present explicit toric construction of moduli space of quasi maps from p1 with two marked points to p1. His theorem that a compact analytic variety in a projective space is algebraic is justly famous. In this paper we introduce and study a ring ltration on rg which is an analogue of the coniveau ltration on the grothendieck ring of a smooth variety. The classical construction is also problematic since the constructed variety chowrx a priori depends on the embedding of x into a projective space. Introduction in this document, we compute the chow ring of the blowup of p3 along the twisted cubic. Hodgeriemann relations for the chow ring, recovering the main result of ahk18.
A model for the orbifold chow ring of weighted projective. The chow ring for the classifying space of go arxiv. We describe the chow rings of moduli spaces of ordered config urations of points on the projective line for arbitrary sufficiently generic. When the scheme is smooth over a field, the chow groups form a ring, not just a graded abelian group. On the cohomology and the chow ring of the classifying space. An introduction to projective spaces over the theory of ordinary commutative rings is in. Brauer groups, root stacks, and the chow ring of the stack of expanded pairs. Chapter 9 projective bundles and their chow rings 323. For example, let x be a smooth complex projective surface. Intersection theory of moduli space of stable npointed curves of genus zero. In this case, the hypersurfaces xi are characterized by their. Miles reid, graded rings and varieties in weighted projective space. Let xbe a projective variety over a noetherian ring and let o x1 be a very ample line bundle on x. The invariant is cohomology and the topological space family is complex projective space get more specific information about complex projective space get more computations of cohomology.
Namely, when is smooth over, define to be the chow group of codimensioncycles on. The chow ring of a classifying space g is a complex algebraic group, h. Contact curves in projective space amorim, e vainsencher, i. Both methods have their importance, but thesecond is more natural. Chow rings, decomposition of the diagonal and the topology of. Preliminaries schemes are of nite type over a eld k. We show that the orbifold chow ring of a root stack over a wellformed weighted projective space can be naturally seen as the jacobian algebra of a function on a singular variety given by a. Let x be a smooth projective toric surface, and hdx the hilbert scheme parametrising the length dzerodimensional subschemes of x. Computations of chow rings and p the mod cohomology motivic of classifying spaces nobuaki yagita faculty of education, ibaragi university. The chow ring of projective space over any field is the ring.
W has a natural structure of projective space and its dimension is given by the hirzebruchriemann. A model for the orbifold chow ring of weighted projective spaces article pdf available in communications in algebra 372 october 2007 with 23 reads how we measure reads. The chow ring of punctual hilbert schemes on toric surfaces laurent evain laurent. Projective morphisms harvard mathematics department. This article describes the value and the process used to compute it of some homotopy invariants for a topological space or family of topological spaces. Calculation of singularities of an imbedding of a generic.
The chow group of zerocycles on x maps onto the integers by the degree homomorphism. The chow ring for the classifying space of go2n saurav bhaumik abstract let go2n be the general orthogonal group scheme the group of orthogonal similitudes. On the cohomology and the chow ring of the classifying. Riemann surfaces and algebraic curves jwr tuesday december 11, 2001, 9. Yof schemes is said to be quasi projective if it factors into an open embedding x. His theorem that a compact analytic variety in a projective space is algebraic is justly fa.
The chow associated forms give a description of the moduli space of the algebraic varieties in projective space. Pdf toric construction and chow ring of moduli space of. Chow rings, decomposition of the diagonal, and the topology. On chow stability for algebraic curves request pdf. P1, which was first proposed by jinzenji and prove that it is a compact orbifold. Invariants of a general cover of p 1 with gabriel bujokassubmitted, 2015. Chow variety can be extended into a chow scheme, e. Projective \n\ space over a ring sage reference manual v9. From the point of view of intersection theory, a basic invariant of xis its chow ring. Sep 26, 2007 on the cohomology and the chow ring of the classifying space of pgl p on the cohomology and the chow ring of the classifying space of pgl p vistoli, angelo 20070926 00. Calculation of singularities of an imbedding of a generic algebraic surface in projective space p3 v. Pdf a model for the orbifold chow ring of weighted. Motivated by the computation of the bpsinvariants on a local calabiyau threefold suggested by s.
The examples of chow rings id like to compute are projective spaces, grassmannians, and flag varieties. Cohomology rings of moduli of point configurations on the projective. In particular, we show that the chow ring is tautological, generated by kappa classes. The chow ring of punctual hilbert schemes on toric surfaces. Mathematics 7800 quantum algebraic geometry spring 2002 0. Find materials for this course in the pages linked along the left. In particular, we determine its additive structure completely, and we reduce the problem of determing its multiplicative structure to a problem in invariant theory. It gives a beautiful solution of an important problem. We will consider the projec tive space pnk over k with points a a0. In topology, for nite groups, a similar ltration has been considered by. The chow ring of the stack of cyclic covers of the projective line. Further it is not clear which functor it is that the chow scheme should. The homogeneous coordinate ring of a projective variety, 5.
We compute the chow ring of the space of trigonal curves. Aurelio carboni, marco grandis, categories of projective spaces, jpaa 110 1996 pp. The ring structure of the integral cohomology can be determined by the ring structure of the mod 2 cohomology. We prove that a general cover of the projective line has a balanced bundle of quadrics f. In section 5 of this paper they mention the keels formula and state the facts needed in the computation of the chow ring. We will now extend our definitions to projective spaces. The chow ring has many advantages and is widely used. Katz, we compute the chow ring and the cohomology ring of the moduli space of stable.
We give a presentation for the chow ring of the moduli space of degree 2 stable maps from 2pointed rational curves to the projective line. We call it chow ltration because of a close relation with the chow ring of the classifying space of g. Brauer groups, root stacks, and the chow ring of the stack of. The chow ring of the stack of cyclic covers of the projective. In section4, we use the decomposition to give simple proofs of poincare duality, the hard lefschetz theorem, and the. W has a natural structure of projective space and its dimension is given by the hirzebruch riemann. A riemann surface is a smooth complex manifold xwithout boundary of complex dimension one. As an application, we will show that the differential polynomial h in ritts remark mentioned above is the chow form of a projective differential variety associated with v. G glv a representation of g, with an open subset u. We also determine its chow ring and compute its poincare polynomial for some lower degree cases. Another nice reference is the paper a compactification of configuration spaces by fultonmacpherson. For which varieties is the natural map from the chow ring to.
190 680 393 969 744 392 1383 1035 1437 1481 1075 461 656 1189 23 1263 924 153 1238 1255 382 279 932 820 398 558 1082 1330 1288 585 274 153 112 1079 787 564 773 1003 531 66 1487 1467 153