The human auditory system is capable of perceiving the direction of a sound source despite reeections oo of walls, ceiling and other interfering objects. This phenomenon, the precedence eeect, has been previously modeled only for synthetic click stimuli. This paper presents a biologically plausible computer simulation for speech, that combines a cross-correlation model with an onset enhancement...

Recent work has studied the fragmentability and σ-fragmentability properties of Banach spaces. Here examples are given that justify the definitions that have been used. The fragmentability and σ-fragmentability properties of the spaces `∞ and `c (Γ ), with Γ uncountable, are determined.

A field K is 0-Hilbertian if K 6= ⋃ni=1 φi(K) for any collection of rational functions φi of degree at least 2, i = 1, . . . ,m. Corvaja and Zannier [CoZ] give an elementary construction for a 0-Hilbertian field that isn’t Hilbertian. There is an obvious generalization of the notion of 0-Hilbertian to g-Hilbertian. Guralnick-Thompson and Liebeck-Saxl have given a partial classification of monod...

We introduce the categories of algebraic σ-varieties and σ-groups over a difference field (K,σ). Under a “linearly σ-closed” assumption on (K,σ) we prove an isotriviality theorem for σ-groups. This theorem yields immediately the key lemma in a proof of the Manin-Mumford conjecture. The present paper uses crucially ideas from [10] but in a model theory free manner. The applications to Manin-Mumf...

Nakayama (Ann. of Math. 42, 1941) showed that over an artinian serial ring every module is a direct sum of uniserial modules. Hence artinian serial rings have the property that each right (left) ideal is a finite direct sum of quasi-injective right (left) ideals. A ring with the property that each right (left) ideal is a finite direct sum of quasi-injective right (left) ideals will be called a ...

Inspired by Fagin’s result that NP = Σ11, we have developed a partial framework to investigate expressibility inside Σ11 so as to have a finer look into NP . The framework uses interesting combinatorics derived from second-order Ehrenfeucht-Fräıssé games and the notion of game types. Some of the results that have been proven within this framework are: (1) for any k, divisibility by k is not exp...