Modified Sch\"odinger dynamics with attractive densities

The linear Schr\"{o}dinger equation does not predict that macroscopic bodies should be located at one place only. Quantum mechanics textbooks generally solve the problem by introducing the projection postulate, which forces definite values to emerge during position measurements; many other interpretations have also been proposed.\ Here, in the same spirit as the GRW and CSL theories, we modify the Schr\"{o}dinger equation in a way that efficiently cancels macroscopic density fluctuations in space.\ Instead of introducing the stochastic dynamics of GRW or CSL, we assume a deterministic dynamics that includes an attraction term towards the density in space of the de Broglie-Bohm position of particles. This automatically ensures macroscopic uniqueness, so that the state vector can be considered as a direct representation of physical reality.Comment: 14 pages, no figure. This is the version accepted by the European Physical Journal, with a few additions in the text and a few more references. A typo has been corrected in Eq (4

On a reverse form of the Brascamp-Lieb inequality

We prove a reverse form of the multidimensional Brascamp-Lieb inequality. Our method also gives a new way to derive the Brascamp-Lieb inequality and is rather convenient for the study of equality cases

Dining Cryptographers with 0.924 Verifiable Collision Resolution

The dining cryptographers protocol implements a multiple access channel in which senders and recipients are anonymous. A problem is that a malicious participant can disrupt communication by deliberately creating collisions. We propose a computationally secure dining cryptographers protocol with collision resolution that achieves a maximum stable throughput of 0.924 messages per round and which allows to easily detect disruptors.Comment: 11 pages, 3 figure

Language discrimination by newborns: Teasing apart phonotactic, rhythmic, and intonational cues

Speech rhythm has long been claimed to be a useful bootstrapping cue in the very first steps of language acquisition. Previous studies have suggested that newborn infants do categorize varieties of speech rhythm, as demonstrated by their ability to discriminate between certain languages. However, the existing evidence is not unequivocal: in previous studies, stimuli discriminated by newborns always contained additional speech cues on top of rhythm. Here, we conducted a series of experiments assessing discrimination between Dutch and Japanese by newborn infants, using a speech resynthesis technique to progressively degrade non-rhythmical properties of the sentences. When the stimuli are resynthesized using identical phonemes and artificial intonation contours for the two languages, thereby preserving only their rhythmic and broad phonotactic structure, newborns still seem to be able to discriminate between the two languages, but the effect is weaker than when intonation is present. This leaves open the possibility that the temporal correlation between intonational and rhythmic cues might actually facilitate the processing of speech rhythm

A Note on Fault Diagnosis Algorithms

In this paper we review algorithms for checking diagnosability of discrete-event systems and timed automata. We point out that the diagnosability problems in both cases reduce to the emptiness problem for (timed) B\"uchi automata. Moreover, it is known that, checking whether a discrete-event system is diagnosable, can also be reduced to checking bounded diagnosability. We establish a similar result for timed automata. We also provide a synthesis of the complexity results for the different fault diagnosis problems.Comment: Note: This paper is an extended version of the paper published in the proceedings of CDC'09, 48th IEEE Conference on Decision and Control and 28th Chinese Control Conference, Shanghai, P.R. China, December 2009

Perception of linguistic rhythm by newborn infants

Previous studies have shown that newborn infants are able to discriminate between certain languages, and it has been suggested that they do so by categorizing varieties of speech rhythm. However, in order to confirm this hypothesis, it is necessary to show that language discrimination is still performed by newborns when all speech cues other than rhythm are removed. Here, we conducted a series of experiments assessing discrimination between Dutch and Japanese by newborn infants, using a speech resynthesis technique to progressively degrade non-rhythmical properties of the sentences. When the stimuli are resynthesized using identical phonemes and artificial intonation contours for the two languages, thereby preserving only their rhythmic structure, newborns are still able to discriminate the languages. We conclude that new-borns are able to classify languages according to their type of rhythm, and that this ability may help them bootstrap other phonological properties of their native language