randformblog on math, physics, art, and design |
It is sometimes interesting to observe how ideas breed. Since some years there has been Ken Perlins vision of a Laser-Leia – or err – a teddybear? – on his marvelous and famous homepage (-> which had been included in the Whitney artport!). Seems last year (more…)
Just the sentence “The model can be used [for] a fast transportation system to students and adults.” seems mysterious to me – what about chimney sweeps, locomotive drivers, and other minorities?
today György Ligeti died.
an exceptional composer, pioneering micropolyphony, fluid in many languages, and unasked filmscore writer
some samples from his work can be found here (audio) and here (score). However, the sound examples can give only a faint idea of the experience a live performance of his work can be.
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This latin sentence (the sower Arepo holds the wheels with effort) is more than a palindrome (a sentence that can be read in both directions). In fact it can be read in all four directions of the square exposing even more symmetry. You can mirror it along its diagonals, but not all the symmetries of a square are present: a rotation by 90 degrees does not map the letters to themselves (pong).
I had the pleasure to give a talk at the Days “Data processing and Geometry” (this is what google makes from the title) at Lyon the first two days of june.
It is quite an experience to attend a scientific meeting when having only a faint idea of the language (the spoken one, not the scientific) :-). While lasting only two days the conference covered quite a widespread range of topics. Especially interesting to me was some introduction into the design of the CGAL library — a collection of robust and efficient algorithms for geometry presented by Sylvain Pion and Raphaelle Chaine. An other interesting talk was from Alain Daurat on discrete tomography of convex sets. The question here is about algorithms that allow the reconstruction of the shape given the sample values along some finite number of directions (and what are the conditions on the choice of directions to ensure a reconstruction is possible). The complete reconstruction of any set given sample data along any discrete straight line was turned into a game by us recently. Many of the talks dealt with (re)construction of shapes: like arithmetic definition for Bresenham circles (Jean-Luc Toutant), a modeler based on the topology of discrete objects (Alain Daurat), or an algorithm for implicit surfaces (Christophe Raffalli)
I myself tried to draw the attention to the Berlin grown software jReality and oorange.
Despite chilling 17 degrees celsius there is 3 days of “Karnival der Kulturen” in Berlin. Here some pictures from the glorious parade….and as one can see the upcoming soccer world championship is sort of
influential. (more…)
one can find the answer at youtube… (more…)
There are days you better not forget. Then there are days that are a catastrophy to forget. And then there are days you didn’t even know of in the first place and if brought to your attention you wish to forget as soon as possible. Like Pi day.
Just a little remark for the ignorant: Pi is not a rational number and in particular it is not equal to 22/7.
…to be able to answer promptly, and I did. I said I didn’t know.
Mark Twain