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N Schreiber

Publications and source records attributed to N Schreiber.

4 recordsLinked to original sources
PubMed2005

Breaking of ergodicity and long relaxation times in systems with long-range interactions.

The thermodynamic and dynamical properties of an Ising model with both short-range and long-range, mean-field-like, interactions are studied within the microcanonical ensemble. It is found that the relaxation time of thermodynamically unstable states diverges logarithmically with system size. This is in contrast with the case of short-range interactions where this time is finite. Moreover, at sufficiently low energies, gaps in the magnetization interval may develop to which no microscopic configuration corresponds. As a result, in local microcanonical dynamics the system cannot move across the gap, leading to breaking of ergodicity even in finite systems. These are general features of systems with long-range interactions and are expected to be valid even when the interaction is slowly decaying with distance.

Journal Article↗
PubMed2001

"What else could he have done?" Creating false answers in child witnesses by inviting speculation.

In 2 experiments (N = 111 children), a suggestive technique for interviewing child witnesses called "inviting speculation" was examined. Children were presented with atypical actions for common objects in a clown show. One week later, the children were asked to speculate (e.g., "What else could he have done with the knife?") in a between-subjects design on all or none of the items (Experiment 1) and in a within-subjects design on part of the items (Experiment 2), thereby getting highly probable speculations (e.g., "to cut"). After a 3-week delay, the experimenters found more highly probable but not more other false answers for the experimental items (Experiment 2). After a 5-6-month delay, the rate of (unspecified) false answers increased compared with the baseline (Experiments 1 and 2). The short-term effect is explained by a speculation-as-misinformation assumption, whereas the long-term effect is explained by the use of a metastrategy.

Child↗