Homological equivalence, modulo algebraic equivalence, is not finitely generated
نویسندگان
چکیده
منابع مشابه
K g is not finitely generated
Let Σg be a closed orientable surface of genus g. The mapping class group Modg of Σg is defined to be the group of isotopy classes of orientationpreserving diffeomorphisms Σg → Σg. Recall that an essential simple closed curve γ in Σg is called a bounding curve, or separating curve, if it is nullhomologous in Σg or, equivalently, if γ separates Σg into two connected components. Let Kg denote the...
متن کاملConfluence Modulo Equivalence in Constraint Handling Rules
Previous results on confluence for Constraint Handling Rules, CHR, are generalized to take into account user-defined state equivalence relations. This allows a much larger class of programs to enjoy the advantages of confluence, which include various optimization techniques and simplified correctness proofs. A new operational semantics for CHR is introduced that reduces notational overhead sign...
متن کاملCOUNTING POINTS MODULO p FOR SOME FINITELY GENERATED SUBGROUPS OF ALGEBRAIC GROUPS
We begin by explaining the basic idea of this paper in a simple case. We write n p for the order of 2 modulo the prime p, so that n p is the number of powers of 2 which are distinct mod p. We have the elementary bounds logp <£ n p ^ p-1. The conjecture of E. Artin on primitive roots asserts that the upper bound is attained for a set of primes with positive density (see Hooley [2] for a discussi...
متن کاملEquivalence Relations in Algebraic Geometry
1. The cycle groups C8. An algebraic variety F i n w-dimensional complex projective space P ( n ) is obtained by equating to zero a finite number of forms Fi(x0, • • • , xn)f • • • , Fm(xo, • • • , xn) with complex coefficients ; F is assumed to be nonempty. If F i s irreducible, that is, if V is not the union of a finite number of proper subvarieties, it is possible to associate with V in seve...
متن کاملElementary Equivalence and Profinite Completions: a Characterization of Finitely Generated Abelian-by-finite Groups
In this paper, we show that any finitely generated abelian-byfinite group is an elementary submodel of its profinite completion. It follows that two finitely generated abelian-by-finite groups are elementarily equivalent if and only if they have the same finite images. We give an example of two finitely generated abelian-by-finite groups G, H which satisfy these properties while G x Z and H x Z...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Publications mathématiques de l'IHÉS
سال: 1983
ISSN: 0073-8301,1618-1913
DOI: 10.1007/bf02953771