22 research outputs found
Input states for quantum gates
We examine three possible implementations of non-deterministic linear optical
cnot gates with a view to an in-principle demonstration in the near future. To
this end we consider demonstrating the gates using currently available sources
such as spontaneous parametric down conversion and coherent states, and current
detectors only able to distinguish between zero or many photons. The
demonstration is possible in the co-incidence basis and the errors introduced
by the non-optimal input states and detectors are analysed
Von Bezold assimilation effect reverses in stereoscopic conditions
Lightness contrast and lightness assimilation are opposite phenomena: in contrast,
grey targets appear darker when bordering bright surfaces (inducers) rather than dark ones; in
assimilation, the opposite occurs. The question is: which visual process favours the occurrence
of one phenomenon over the other? Researchers provided three answers to this question. The
first asserts that both phenomena are caused by peripheral processes; the second attributes their
occurrence to central processes; and the third claims that contrast involves central processes,
whilst assimilation involves peripheral ones. To test these hypotheses, an experiment on an IT
system equipped with goggles for stereo vision was run. Observers were asked to evaluate the
lightness of a grey target, and two variables were systematically manipulated: (i) the apparent
distance of the inducers; and (ii) brightness of the inducers. The retinal stimulation was kept
constant throughout, so that the peripheral processes remained the same. The results show that
the lightness of the target depends on both variables. As the retinal stimulation was kept constant, we
conclude that central mechanisms are involved in both lightness contrast and lightness assimilation
Minimal reporting guideline for research involving eye tracking (2023 edition)
A guideline is proposed that comprises the minimum items to be reported in research studies involving an eye tracker and human or non-human primate participant(s). This guideline was developed over a 3-year period using a consensus-based process via an open invitation to the international eye tracking community. This guideline will be reviewed at maximum intervals of 4 years
Quantum computation with coherent states
We extend a previous proposal for performing deterministic quantum computation using coherent states and linear optics by examining a new version of one of the gates which offers several advantages