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991.
We describe the algebras of semi-invariants on the varieties of regular representations of canonical algebras. In particular,
we show that these algebras are polynomial algebras or complete intersections.
Received: 29 March 1999 相似文献
992.
We consider the family of fibres of a polynomial function f on a smooth noncompact algebraic real surface and we characterise the regular fibres of f which are atypical due to their asymptotic behaviour at infinity. We compare to the similar problem in the complex case.
Received: 5 May 1998 / Revised version: 20 March 1999 相似文献
993.
Vincent Thilliez 《manuscripta mathematica》1999,99(2):203-222
We give sufficient conditions of infinite determinacy (in the sense of Mather) with respect to right equivalence, in subrings
of C
∞ (ℝ
n
,0) defined by estimates on successive derivatives, such as rings of Gevrey germs. In this quantitative setting, a defect
(hidden in the classical C
∞ case) appears between the regularity of equivalent germs and the regularity of local diffeomorphisms of (ℝn,0) giving the equivalence. Our conditions yield precise estimates of this defect, related to some suitable Łojasiewicz exponents
of critical loci. We also show that the result is sharp in general.
Received: Received: 27 May 1998 相似文献
994.
B. Anchouche 《manuscripta mathematica》1999,100(4):423-436
We show that over some smooth projective varieties every semistable Higgs logarithmic vector bundle is semistable in the ordinary
sense, hence satisfies Bogomolov inequality. More generaly, we prove that semistable Higgs parabolic vector bundles of rank
two over smooth projective varieties of dimension ≥ 2 satisfy the “parabolic” 'Bogomolov inequality
Received: 1 March 1999 / Revised version: 11 June 1999 相似文献
995.
Xiaoping Xu 《manuscripta mathematica》1999,100(4):489-518
In this paper, we introduce two new families of infinite-dimensional simple Lie algebras and a new family of infinite-dimensional
simple Lie superalgebras. These algebras can be viewed as generalizations of the Block algebras.
Received: 3 March 1999 相似文献
996.
Ralph Howard 《manuscripta mathematica》1999,99(4):471-483
For a complete Riemannian manifold M with compact boundary ∂M denote by $\Cut$ the cut locus of $\f M$ in M. The rolling radius of M is roll(M)≔ dist(∂M, ?∂
M
). Let Focal(∂M) be the focal distance of ∂M in M. Then conditions are given that imply the equality roll(M)= Focal(∂M). This generalizes Blaschke's rolling theorem from bounded convex domains in Euclidean space to more general Euclidean domains
and to Riemannian manifolds with boundary.
Received: 28 August 1998 / Revised version: 8 February 1999 相似文献
997.
A valued field K is called p-henselian, if its valuation extends uniquely to the maximal Galois p-extension K(p) of K. In this paper we determine the structure of Gal(K(p)/K) in case the residue characteristic is different from p. We do not assume that K contains a p-th root of unity.
Received: 3 February 1999 相似文献
998.
Let H\G be a causal symmetric space sitting inside its complexification H
ℂ\G
ℂ. Then there exist certain G-invariant Stein subdomains Ξ of H
ℂ\G
ℂ. The Haar measure on H
ℂ\G
ℂ gives rise to a G-invariant measure on Ξ. With respect to this measure one can define the Bergman space B
2(Ξ) of square integrable holomorphic functions on Ξ. The group G acts unitarily on the Hilbert space B
2(Ξ) by left translations in the arguments. The main result of this paper is the Plancherel Theorem for B
2(Ξ), i.e., the disintegration formula for the left regular representation into irreducibles.
Received: Received: 23 November 1998 相似文献
999.
In this paper, we propose a non-interior continuation method for solving generalized linear complementarity problems (GLCP)
introduced by Cottle and Dantzig. The method is based on a smoothing function derived from the exponential penalty function
first introduced by Kort and Bertsekas for constrained minimization. This smoothing function can also be viewed as a natural
extension of Chen-Mangasarian’s neural network smooth function. By using the smoothing function, we approximate GLCP as a
family of parameterized smooth equations. An algorithm is presented to follow the smoothing path. Under suitable assumptions,
it is shown that the algorithm is globally convergent and local Q-quadratically convergent. Few preliminary numerical results
are also reported.
Received September 3, 1997 / Revised version received April 27, 1999?Published online July 19, 1999 相似文献
1000.
Carlo Gasbarri 《manuscripta mathematica》1999,98(4):453-475
Let K be a number field and its ring of integers. Let be a Hermitian vector bundle over . In the first part of this paper we estimate the number of points of bounded height in (generalizing a result by Schanuel). We give then some applications: we estimate the number of hyperplanes and hypersurfaces
of degree d>1 in of bounded height and containing a fixed linear subvariety and we estimate the number of points of height, with respect to
the anticanonical line bundle, less then T (when T goes to infinity) of ℙ
N
K
blown up at a linear subspace of codimension two.
Received: 20 February 1998 / Revised version: 9 November 1998 相似文献