In this paper we find sufficient conditions on primitive inverse topological semigroup S under which: the inversion inv : (H(S)) (H(S)) is continuous; we show that every topologically periodic countable compact primitive inverse topological semigroups with closed H-classes is topologically isomorphic to an orthogonal sum P i2= Bi (Gi) of topological Brandt extensions Bi (Gi) of countably compac...

Voiced speech is characterized by qualitatively rich mode locking phenomena linking harmonically excited acoustic modes of the vocal tract. Due to the strong instationarity of speech, a differentiated analysis of these modes cannot be achieved with the help of a linear, time invariant source and filter model (based on stationary sources). As alternative, the characteristic mode locking is descr...

The causality properties of space-time models with traversable wormholes are considered. It is shown that relativity principle cannot be applied to the motion of the wormhole’s mouths in the outer space and the dynamical wormhole transformation into the time machine is impossible. The examples of both causal and noncausal spacetime models with traversable wormholes are also considered. Some pro...

Let S be a topological semigroup acting on a topological space X. We develop the theory of (weakly) almost periodic functions on X, with respect to S, and form the (weakly) almost periodic compactifications of X and S, with respect to each other. We then consider the notion of an action of Son a Banach space, and on its dual, and after defining S-invariant means for such a space, we give a...

We discuss the geometry of homogeneous Ricci solitons. After showing the nonexistence of compact homogeneous and noncompact steady homogeneous solitons, we concentrate on the study of left invariant Ricci solitons. We show that, in the unimodular case, the Ricci soliton equation does not admit solutions in the set of left invariant vector fields. We prove that a left invariant soliton of gradie...

Submitted for the MAR16 Meeting of The American Physical Society Classification of interacting fermionic phases by dimensional reduction RAQUEL QUEIROZ, ESLAM KHALAF, Max Planck Institute for Solid State Physics, ADY STERN, Weizmann Institute of Science — Topological phases of noninteracting fermions are classified in each spatial dimension according to their symmetry class, in a periodic way [...

One of the main topological invariants that characterizes several topologically-ordered phases is many-body Chern number (MBCN). Paradigmatic examples include fractional quantum Hall phases, which are expected to be realized in different atomic and photonic platforms near future. Experimental measurement numerical computation this invariant conventionally based on linear-response techniques req...

The aim of this paper is to study and compare the dynamics of two classes of periodic point free homeomorphisms of the open annulus, homotopic to the identity. First, we consider skew products over irrational rotations (often called quasiperiodically forced monotone maps) and derive a decomposition of the phase space that strengthens a classification given by J. Stark. There exists a sequence o...

Linear time-invariant (LTI) filter is the most common method to the edge detection. On the condition of first-order filter, an edge is considered as an abrupt variation in gray level between two neighbor pixels. Then the aim is to find out the points in the image which the first-order derivative of the gray level is of high magnitude. The root mean square value (RMS) is often used as the thresh...

In this paper, we describe the primitive ideal space of the $C^*$-algebra $C^*(mathcal G)$  associated to the ultragraph $mathcal{G}$. We investigate the structure of the closed ideals of the quotient ultragraph $  C^* $-algebra  $C^*left(mathcal G/(H,S)right)$ which contain no nonzero set projections and then we characterize all non gauge-invariant primitive ideals. Our results generalize the ...