Results 11  20
of
182
Querying the guarded fragment
 PROCEEDINGS OF THE 25TH ANNUAL IEEE SYMPOSIUM ON LOGIC IN COMPUTER SCIENCE, LICS 2010
, 2010
"... Evaluating a Boolean conjunctive query q against a guarded firstorder theory ϕ is equivalent to checking whether ϕ ∧ ¬q is unsatisfiable. This problem is relevant to the areas of database theory and description logic. Since q may not be guarded, well known results about the decidability, complexity ..."
Abstract

Cited by 38 (12 self)
 Add to MetaCart
Rosati’s finite chase, we prove for guarded theories ϕ and (unions of) conjunctive queries q that (i) ϕ  = q iff ϕ =fin q, that is, iff q is true in each finite model of ϕ and (ii) determining whether ϕ  = q is 2EXPTIMEcomplete. We further show the following results: (iii) the existence of polynomial
Milman phenomenon, Urysohn metric spaces, and extremely amenable groups
 Israel J. Math
"... Abstract. In this paper we further study links between concentration of measure in topological transformation groups, existence of fixed points, and Ramseytype theorems for metric spaces. We prove that whenever the group Iso(U) of isometries of Urysohn’s universal complete separable metric space U, ..."
Abstract

Cited by 35 (11 self)
 Add to MetaCart
Abstract. In this paper we further study links between concentration of measure in topological transformation groups, existence of fixed points, and Ramseytype theorems for metric spaces. We prove that whenever the group Iso(U) of isometries of Urysohn’s universal complete separable metric space U
Arithmetic of singular moduli and class polynomials
, 2005
"... We investigate divisibility properties of the traces and Hecke traces of singular moduli. In particular we prove that, if p is prime, these traces satisfy many congruences modulo powers of p which are described in terms of the factorization of p in imaginary quadratic fields. We also study generaliz ..."
Abstract

Cited by 18 (3 self)
 Add to MetaCart
We investigate divisibility properties of the traces and Hecke traces of singular moduli. In particular we prove that, if p is prime, these traces satisfy many congruences modulo powers of p which are described in terms of the factorization of p in imaginary quadratic fields. We also study
Markov traces and knot invariants related to IwahoriHecke algebras of type B, J. fur die reine und angewandte Mathematik 482,
, 1997
"... Introductory remarks on knots, braids and trace functions In classical knot theory we study knots inside the 3sphere modulo isotopy. Using the Alexander and Markov theorem, we can translate this into a purely algebraic setting in terms of Artin braid groups modulo an equivalence relation generated ..."
Abstract

Cited by 21 (8 self)
 Add to MetaCart
Introductory remarks on knots, braids and trace functions In classical knot theory we study knots inside the 3sphere modulo isotopy. Using the Alexander and Markov theorem, we can translate this into a purely algebraic setting in terms of Artin braid groups modulo an equivalence relation
Vassiliev Invariants on Fibered and Mutually Obverse Knots
, 1997
"... . We use the new approach of braiding sequences and the Stanford construction to prove that there is no way to extract information on fiberedness from Vassiliev invariants and that the chirality sensitivity of Vassiliev invariants depends mainly only on the parity of their degree. Keywords: Vassi ..."
Abstract

Cited by 3 (1 self)
 Add to MetaCart
. We use the new approach of braiding sequences and the Stanford construction to prove that there is no way to extract information on fiberedness from Vassiliev invariants and that the chirality sensitivity of Vassiliev invariants depends mainly only on the parity of their degree. Keywords
On Solving Universally Quantified Horn Clauses
"... Program proving can be viewed as solving for unknown relations (such as loop invariants, procedure summaries and so on) that occur in the logical verification conditions of a program, such that the verification conditions are valid. Generic logical tools exist that can solve such problems modulo ce ..."
Abstract

Cited by 16 (2 self)
 Add to MetaCart
Program proving can be viewed as solving for unknown relations (such as loop invariants, procedure summaries and so on) that occur in the logical verification conditions of a program, such that the verification conditions are valid. Generic logical tools exist that can solve such problems modulo
Submitted to: A framework for proof certificates in finite state exploration
"... Model checkers use automated state exploration in order to prove various properties such as reachability, nonreachability, and bisimulation over state transition systems. While model checkers have proved valuable for locating errors in computer models and specifications, they can also be used to p ..."
Abstract
 Add to MetaCart
Model checkers use automated state exploration in order to prove various properties such as reachability, nonreachability, and bisimulation over state transition systems. While model checkers have proved valuable for locating errors in computer models and specifications, they can also be used
Calculus of clovers and finite type invariants . . .
, 2001
"... A clover is a framed trivalent graph with some additional structure, embedded in a 3manifold. We define surgery on clovers, generalizing surgery on Y{graphs used earlier by the second author to define a new theory of finitetype invariants of 3manifolds. We give a systematic exposition of a topolo ..."
Abstract

Cited by 13 (2 self)
 Add to MetaCart
topological calculus of clovers and use it to deduce some important results about the corresponding theory of nite type invariants. In particular, we give a description of the weight systems in terms of unitrivalent graphs modulo the AS and IHX relations, reminiscent of the similar results for links. We
TRUNCATIONS OF LEVEL 1 OF ELEMENTS IN THE LOOP GROUP OF A REDUCTIVE GROUP
, 2009
"... We generalize the notion of EkedahlOort strata to elements in the loop group of any connected reductive group, and call the resulting discrete invariant the truncation of level 1 of the element. We give conditions for the Newton points occurring among the elements of a given truncation of level 1 ..."
Abstract

Cited by 14 (2 self)
 Add to MetaCart
1 and especially for the generic Newton point in a given truncation stratum. We prove that truncation strata are locally closed and give a description of the closure of each stratum. We also translate our results back to the original EkedahlOort stratification of the reduction modulo p of Shimura
INVARIANTS OF DEGREE 3 AND TORSION IN THE CHOW GROUP OF A VERSAL FLAG
"... Abstract. We prove that the group of normalized cohomological invariants of degree 3 modulo the subgroup of semidecomposable invariants of a semisimple split linear algebraic group G is isomorphic to the torsion part of the Chow group of codimension 2 cycles of the respective versal Gflag. In parti ..."
Abstract

Cited by 1 (0 self)
 Add to MetaCart
Abstract. We prove that the group of normalized cohomological invariants of degree 3 modulo the subgroup of semidecomposable invariants of a semisimple split linear algebraic group G is isomorphic to the torsion part of the Chow group of codimension 2 cycles of the respective versal G
Results 11  20
of
182