DATA-log

V. S. Zuev, G. Ya. Zueva
(Submitted on 3 Nov 2008 (v1), last revised 4 Nov 2008 (this version, v2))

Abstract: The paper is of a methodological character and has as a goal to give a brief description of the concept of theory and practical application of very slow optical plasmons. They exist on the metal-dielectric boundaries, namely, on very thin metal films and fibers and as standing waves on metal spheres and ellipsoids. The material presented in the paper features by widening the common concepts of electromagnetic modes of various spaces, of the probability of spontaneous emission, of creation of optical images, of the limits of optical focusing, and of the photon linear momentum. All mentioned studies are completed in recent years. The problem of the photon momentum in a dielectric medium was the topic of irreconcilable disputes for 100 years starting in the time of appearing of Minkowski and Abraham famous papers. Various practical applications are surveyed: the experiments with a great intensification of an atom spontaneous emission into a plasmonic field mode of a metal nanoparticle, the experiments on focusing optical radiation into a spot that substantially smaller than a diffraction limited spot, a so called near perfect Pendry lens that produces the image with details that substantially smaller than defined by diffraction, and lastly, the concept of hundredfold and more magnification of a photon mechanical linear momentum in a plasmon. The work completed is supported by RFBR, grants Nos 05-02-19647, 07-02-01328.

http://arxiv.org/abs/0811.0810

I got around programming some perl and php hacks to interface a web page with the liquidsoap server running the radio. Enjoy.

http://www.punainen.org/~biotek/radio_free_robotron/request.php

Craig F. Bohren
Department of Meteorology, Pennsylvania State University, University Park, Pennsylvania 16802

(Received 11 February 1982; accepted 26 April 1982)

A particle can indeed absorb more than the light incident on it. Metallic particles at ultraviolet frequencies are one class of such particles and insulating particles at infrared frequencies are another. In the former strong absorption is associated with excitation of surface plasmons; in the latter it is associated with excitation of surface phonons. In both instances the target area a particle presents to incident light can be much greater than its geometrical cross-sectional area. This is strikingly evident from the field lines of the Poynting vector in the vicinity of a small sphere illuminated by a plane wave. ©1983 American Association of Physics Teachers

Link to citation.

Having studied the fundamentals of quantum mechanics from the perspective of numerical computation it has become obvious that stability is a major drawback in most fast numerical approaches. The best scheme to tackle with the issue is by Visscher whose explicit algorithm is both fast and stable. Accuracy is not my biggest concern since I’m mostly interested in visualization of the quantum mechanical world but the algorithm holds very well. The algorithm is second order accurate, there is some dispersion of the wave packet however. It is also straightforward to extend it to n-dimensional space.

My processing example applet of the 1D time-dependent Schrödinger wave equation with the source code is at http://www.punainen.org/~biotek/visscher1d

Reference to the original paper: P.B. Visscher “A fast explicit algorithm for the time-dependent Schrödinger equation”, Computers in Physics Nov/Dec 1991, 596-8

Here’s something interesting from youtube..

After a few hours of playing around with SSE intrinsics I managed to cut the cpu cycles in half (more or less).

Here’s the link:
http://www.punainen.org/~biotek/string_sse.dll

Stumbled on this old looking science documentary on youtube by chance. Features nice handdrawn graphics and footage from bubble chambers.

Another crazy idea I had which turned into a VST plugin is a spectral mirror. I’m not really sure if that is an appropriate name for it. What it does is that it takes a band of frequencies (for example frequencies 0 Hz thru 4 Hz) and flips it around so that a high frequency becomes a low one and a low becomes a high frequency. How it does this is based on modulation; it modulates the band of frequencies thru the zero frequency aided with steep filtering to remove unwanted sidebands.

The result sounds unnatural because the frequencies aren’t harmonic anymore. The effect is best on human speech, since it really tricks your perception of it. I guess it’s due to the time domain having roughly the same characteristics but the frequencies aren’t perceived anymore as speech. In other words it almost sounds like speech in some weird way but is still unintelligible.

Here is an example. It’s a talk on Kurt Gödel by Rebecca Goldstein (http://www.edge.org/3rd_culture/goldstein05/goldstein05_index.html)

The original talk:

http://www.punainen.org/~biotek/gödel.mp3

The talk thru the mirror vst:

http://www.punainen.org/~biotek/gödel_mirror.mp3

Here is a link to the win32 dynamic link library:

http://www.punainen.org/~biotek/mirror.dll

I’ve had this plan to put together a simple string reverb sort of thing since I studied basic wave functions a while ago. Well, now i finally got to it and put together some code. The mathematics behind it is the usual one dimensional partial differential equation. I consider it to be in alpha stage, you can get very loud noises if you introduce quick discontinuous parameter changes so beware. However it does work nice enough, even if the code is not optimized in any way at all.

Here is a link to the win32 vst dll.  If you happen to try it I’d like to know what you think of it and if there were any problems.

http://www.punainen.org/~biotek/string.dll

Here is a small example mp3 I did with the plugin, feeding it from a sine osc modulated with a s/h.

http://www.punainen.org/~biotek/space_string.mp3