In this paper we give various equivalent characterizations of upper estimates of heat kernels of regular, conservative and local Dirichlet forms on doubling spaces, from both the analytic and probabilistic points of view. The first part of this paper uses purely analytic arguemtn, while the second part focuses on the probabilistic aspects where the exit time plays an important role.

Growing layers on elastic substrates are capable of creating a wide variety of surface morphologies. Moderate growth generates a regular pattern of sinusoidal wrinkles with a homogeneous energy distribution. While the critical conditions for periodic wrinkling have been extensively studied, the rich pattern formation beyond this first instability point remains poorly understood. Here we show th...

In the psychological refractory period (PRP) paradigm, two unmasked targets are presented, each of which requires a speeded response. Response times to the second target (T2) are slowed when T2 is presented shortly after the first target (T1). Electrophysiological studies have previously shown that the P3 event-related potential component is not delayed during T2 response slowing in the PRP par...

Psychologists often dismiss introspection as an inappropriate measure, yet subjects readily volunteer detailed descriptions of the time and effort that they spent on a task. Are such reports really so inaccurate? We asked subjects to perform a psychological refractory period experiment followed by extensive quantified introspection. On each trial, just after their objective responses, subjects ...

Psychological research has documented again and again marked performance decrements whenever humans perform 2 or more tasks at the same time. In fact, the available evidence seems to suggest that any type of behavior is subject to such limitations. The present experiments employed the psychological refractory period (PRP) paradigm to identify a clear exception to this rule: Unconditioned reflex...

The goal of the present experiment was to test the predictions of Central Bottleneck and Central Capacity Sharing models. According to the Central Bottleneck model, dual task interference, as observed in the PRP paradigm, is caused by an all-or-none bottleneck in information processing. The Central Capacity Sharing model postulates that dual task interference is caused by a capacity limited pro...

We construct embedded closed minimal surfaces in the round three-sphere S(1), resembling two parallel copies of the Clifford torus, joined by m small catenoidal bridges symmetrically arranged along a square lattice of points on the torus.

Identifying the precise locus of general cognitive ability (g) in the flow of information between perception and action is an important goal of differential psychology. To localize the negative correlation between g and reaction time to a specific processing stage, we administered a speeded number-comparison task to two groups differing in average g. The participants had to respond to two stimu...

We construct quasiconformal mappings in Euclidean spaces by integration of a discontinuous kernel against doubling measures with suitable decay. The differentials of mappings that arise in this way satisfy an isotropic form of the doubling condition. We prove that this isotropic doubling condition is satisfied by the distance functions of certain fractal sets. Finally, we construct an isotropic...