We study monodromies of plane curve singularities and pseudo-periodic homeomorphisms oriented surfaces with boundary using tête-à-tête graphs twists. A twist is a generalisation the classical Dehn twist. introduce class mixed twists, prove that twists contain irreducible singularities. In sequel paper, fourth author B. Sigurdsson have extended this to reducible case.

In this paper, we characterize each of various forms T0, T1, T2, and pre-Hausdorff extended pseudo-quasi-semi metric spaces as well examine how these generalizations are related. Moreover, give some invariance properties T2 investigate the relationship among irreducible Ti,i = 1,2 spaces. Finally, present Urysohn?s Lemma Tietze Extention Theorem for

Let o be a complete discrete valuation domain with finite residue field. In this paper we describe the irreducible representations of the groups Aut(M) for any finite o-module M of rank two. The main emphasis is on the interaction between the different groups and their representations. An induction scheme is developed in order to study the whole family of these groups coherently. The results ob...

We study conditions on a C∗-dynamical system (A,G,α) under which induction of primitive ideals (resp. irreducible representations) from stabilizers for the action of G on the primitive ideal space Prim(A) give primitive ideals (resp. irreducible representations) of the crossed product A⋊α G. The results build on earlier results of Sauvageot [17] and others, and will correct a (possibly overly o...

The aim of this paper is to generalize the‎‎notion of pseudo-almost valuation domains to arbitrary‎ ‎commutative rings‎. ‎It is shown that the classes of chained rings‎ ‎and pseudo-valuation rings are properly contained in the class of‎ ‎pseudo-almost valuation rings; also the class of pseudo-almost‎ ‎valuation rings is properly contained in the class of quasi-local‎ ‎rings with linearly ordere...

We calculate the real rank and stable rank of CCR algebras which either have only finite dimensional irreducible representations or have finite topological dimension. We show that either rank of A is determined in a good way by the ranks of an ideal I and the quotient A/I in four cases: When A is CCR; when I has only finite dimensional irreducible representations; when I is separable, of genera...

In this paper, we introduce a modified Van der Waerden algorithm to decompose a variety into the union of irreducible varieties. We give an effective representation for irreducible varieties obtained by the algorithm, which allows us to obtain an irredundant decomposition easily. We show that in the zero dimensional case, the polynomial systems for the irreducible varieties obtained in the Van ...

For a radical monomial ideal I in a normal semigroup ring k[Q], there is a unique minimal irreducible resolution 0 → k[Q]/I → W 0 → W 1 → · · · by modules W i of the form ⊕ j k[Fij ], where the Fij are (not necessarily distinct) faces of Q. That is, W i is a direct sum of quotients of k[Q] by prime ideals. This paper characterizes Cohen–Macaulay quotients k[Q]/I as those whose minimal irreducib...

We give the definition of D-invariant points on an irreducible algebraic hypersurface V in RN. show that every regular point quadratic RN is D-invariant. prove local Taylor interpolation projector at a 2 ideal if and only

We compute moduli spaces of Bridgeland stable objects on an irreducible principally polarized complex abelian surface (T, `) corresponding to twisted ideal sheaves. We use Fourier-Mukai techniques to extend the ideas of Arcara and Bertram to express wall-crossings as Mukai flops and show that the moduli spaces are projective.