Archive for the ‘Physics’ Category

The direction of science

Tuesday, March 30th, 2010

Science as it is defined today revolves around a method of cycling experiment and theory. At the universities this cycle is taught as the scientific method. And clearly defines a direction going from observation to theory and round and round until the theory fits the empirical data.
The method as such is quite sound, and a minimum of bias from human expectation is achieved if the observer/scientist keeps evolving the method and theory based on observation.

In modern physics, especially high energy particle physics, things have gotten a bit reversed. Experiments takes years to build, and just as long to
. On the other hand theories can be produced at the flick of a neuron. As a result of this decrepancy between time to invent a theory and time to produced data have grown larger and larger. Even worse, a disconnect between the people building a theory and people producing experimental data have grown as well. Optimally it should be the same person devising theory and experiment.

Todays physics is basically a game of catching up with fantasy rather then describing reality, no matter how enchanting the thought of extra dimensions, time travel and super strings may be, it is so far just a figment of imagination without much basis in reality.

While it’s easy to get caught up in a dream, especially one as profound as the one modern theoretical particle physics provides, it is so far, just that – a dream.

Atmospheric reentry simulation in Javascript

Sunday, June 14th, 2009

The following is the altitude of a reentry vehicle, on its decent through the atmosphere.
What makes this interesting is the way of execution: notice the browser window? The entire simulation is running in javascript, using my javascript classes jVector and jMatrix. The plot is done in jPlot2D (pre-release), utilizing RaphaelJS.

The mathematics comes from this source.

Posted in Physics, eScience, programming | Comments Off

Einstein and beyond

Monday, November 21st, 2005

Just a little heads up: Cern (the ones who collide atoms and invented the web) have arranged a large Einstein event December 1. have a peek at the program here: http://beyond-einstein.web.cern.ch/beyond-einstein/index.html

Fitting code for mathematica

Saturday, November 27th, 2004

I’m doing a lot of datafitting at the moment, so I have developed a script for mathematica,
that does the work for me, it is minded on picoscope data, but hey, I’m posting this
so I can fetch it form whereever I must be..

SetDirectory["/Users/mdj/Desktop/rod/rulledata/clean"];

“Vælg en datafil på formatet tid i millisekunder : spænding i millivolt”;

rawdata = Import["4.txt", "Table"];

“Vælg en kalibreringsfil, i formatet meter : volt”;

rawkali = Import["kali.txt", "Table"];

“Angiv et interval hvor du vil fitte”;

fitinterval = 466;

“Angiv en funktion, ved andet end x^2, skal du tage højde for at differentiere korrekt”;

fitfunktion = x^2;

“Plotter input data”;

rawplot = ListPlot[rawdata,

PlotJoined -> True, PlotStyle -> {RGBColor[0, 1, 1],

RGBColor[0, 1, 0]}]

“Transformerer tid fra milliskunder til sekunder”;

rawtid = rawdata[[All, 1]]/1000000;

“Transformerer millevolt om til meter”;

rawvolt = rawdata[[All, 2]]/1000/D[Fit[rawkali, {1, x}, x], x];

“Fitter og viser grafer”;

kalibra = Table[{rawtid[[i]], rawvolt[[i]]}, {i, 1, Length[rawtid]}];

fitted = Fit[Take[kalibra, {1, fitinterval}], {1, x, fitfunktion}, x];

Show[ListPlot[Take[kalibra, {1, fitinterval}],

PlotJoined -> True], Plot[fitted, {x, 0,

1}, PlotStyle -> {RGBColor[1, 0, 0],

RGBColor[0, 0, 1]}], AxesLabel -> {”[s]“, “[m]“}];

“Den fittede funktion”

fitted

“Finder accelerationen for en andengrads ligning”

Abs[D[D[fitted, x], x]]