A corpuscular simulation model of optical phenomena that does not require the knowledge of the solution of a wave equation of the whole system and reproduces the results of Maxwell's theory by generating detection events one-by-one is presented. The event-based corpuscular model is shown to give a unified description of multiple-beam fringes of a plane parallel plate, singlephoton Mach-Zehnder interferometer, Wheeler's delayed choice, photon tunneling, quantum erasers, two-beam interference, double-slit, and Einstein-Podolsky-Rosen-Bohm and Hanbury Brown-Twiss experiments.

We demonstrate that networks of locally connected processing units with a primitive learning capability exhibit behavior that is usually only attributed to quantum systems. We describe networks that simulate single-photon beam-splitter and Mach-Zehnder interferometer experiments on a causal, event-by-event basis and demonstrate that the simulation results are in excellent agreement with quantum theory.( * )

It is shown that the basic equations of quantum theory can be obtained from a straightforward application of logical inference to experiments for which there is uncertainty about individual events and for which the frequencies of the observed events are robust with respect to small changes in the conditions under which the experiments are carried out.Keywords: logical inference, quantum theory, inductive logic, probability theory 10 from classical (or quantum) mechanics is lacking and therefore the answer should be "no" but in practice this does not matter too much. Our belief in thermodynamics is not based on mathematical deduction but on its power to account for everyday experience.It has been emphasized many times that our description of physical phenomena at some level of observation is essentially independent of our view of "underlying" levels [2]. In the present paper, we apply the 15 same world view to nonrelativistic quantum theory. Adopting this view immediately distinguishes our line of thinking from approaches that assume an underlying ontology [3, 4,5,6, 7] or formulate quantum theory Email addresses: h.a.de.raedt@rug.nl (Hans De Raedt), M.Katsnelson@science.ru.nl (Mikhail I. Katsnelson), 1. There is no quantum world. There is only an abstract physical description. It is wrong to think that the task of physics is to find out how nature is. Physics concerns what we can say about nature [45]. 302. Physics is to be regarded not so much as the study of something a priori given, but rather as the development of methods of ordering and surveying human experience. In this respect our task must be to account for such experience in a manner independent of individual subjective judgment and therefore objective in the sense that it can be unambiguously communicated in ordinary human language [46]. 3. The physical content of quantum mechanics is exhausted by its power to formulate statistical laws 35 governing observations under conditions specified in plain language [46].The first two sentences of the first quote may be read as a suggestion to dispose of, in Mermin's words [47], the "bad habit" to take mathematical abstractions as the reality of the events (in the everyday sense of the word) that we experience through our senses. Although widely circulated, these sentences are reported by Petersen [45] and there is doubt that Bohr actually used this wording [48]. The last two sentences of the first 40 quote and the second quote suggest that we should try to describe human experiences (confined to the realm of scientific inquiry) in a manner and language which is unambiguous and independent of the individual subjective judgment. Of course, the latter should not be construed to imply that the observed phenomena are independent of the choices made by the individual(s) in performing the scientific experiment [49].The third quote suggests that quantum theory is a powerful language to describe a certain class of 45 statistical experiments but remains vague about the properties of the class. Similar views were expres...

Birds-of-paradise are nature's prime examples of the evolution of color by sexual selection. Their brilliant, structurally colored feathers play a principal role in mating displays. The structural coloration of both the occipital and breast feathers of the bird-of-paradise Lawes' parotia is produced by melanin rodlets arranged in layers, together acting as interference reflectors. Light reflection by the silvery colored occipital feathers is unidirectional as in a classical multilayer, but the reflection by the richly colored breast feathers is threedirectional and extraordinarily complex. Here we show that the reflection properties of both feather types can be quantitatively explained by finite-difference time-domain modeling using realistic feather anatomies and experimentally determined refractive index dispersion values of keratin and melanin. The results elucidate the interplay between avian coloration and vision and indicate tuning of the mating displays to the spectral properties of the avian visual system. biophotonics | body colors | courtship | signaling | reflectance B irds-of-paradise are best known for their magnificent coloration. Living isolated on Papua New Guinea and its satellite islands (1), the absence of predators has allowed these birds to become extremely specialized for female sexual selection (2). Male birds-of-paradise have evolved extravagant ornamental traits, with intricate sounds and ritualized sets of dance steps and movements accompanied by simultaneous elaborate feather movements, all combined in beautiful displays to win the favor of females (1-4). Among the 39 species of birds-of-paradise almost all colors of the rainbow can be found, and often the males advertise themselves with brilliant, vivid colors framed within a jet-black background. The females on the other hand have dull brownish plumage which has remained in its ancestral color state (1, 2).Whereas the biological purpose of the colorful displays is relatively well understood (1, 2), the coloration mechanisms of the birds' displays and the connection to the visual system of the animals are poorly explored. Feather coloration can be generally categorized in two forms: pigmentary and structural. Randomly arranged, inhomogeneous media containing pigments are colored, because the pigments absorb the diffusely scattered light in a restricted wavelength range. For instance, carotenoids cause the colorful yellow or red feathers of many songbirds (5), and the ubiquitous, broad-band absorbing pigment melanin causes feathers to be black (6). Structural colors occur in feather barbs due to quasiordered spongy structures, and in feather barbules due to melanosomes--nanosized, melanin-containing granules--regularly arranged in layers within a keratin matrix, resulting in directional reflections because of constructive interference (7-11). Differences in the morphology of the structural colored feathers, i.e., in the dimensions of the spongy structured barbs or the melanosome multilayers in the barbules, can modify the color of the ...