Francis Poulenc - Rapsodie Negre

To fall in the void as I fell: none of you knows what that means… I went down into the void, to the most absolute bottom conceivable, and once there I saw that the extreme limit must have been much, much farther below, very remote, and I went on falling, to reach it.” [Cosmicomics, Italo Calvino]

Apple Xserve xeon Linux/Debian armed

Finally at my Departement we succesfully converted an  unsed  Apple xserve  cluster to a full functional Linux/Debian machine.

The cluster is make up of eleven node connected by Myrinet 10G low latency network and each node is a composed by a dual 4x cores Intel Xeon 2.8 Ghz Harpertown with 10Gb of DDR2 for a total of 88 cores. It is a quite old and small machine and hence was unused. We thought that  it could have been useful if well re-configured as an ad-hoc machine for small sized scientific computation session, as  developing and testing platform of parallel application or for training of undergraduate students that can experience directly with a real parallel machine. So we decided to cast a new light on it by configuring it as a Debian cluster (according to google just few people did it). 10949741_766948060061020_241789111_n

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The Grossone Numeral System

A recently developed computational methodology for executing numerical calculations with infinities and infinitesimals. The approach developed has a pronounced applied character and is based on the principle “The part is less than the whole” introduced by the ancient Greeks. This principle is applied to all numbers (finite, infinite, and infinitesimal) and to all sets and processes (finite and infinite).(Ya. D. Sergeyev)

 A brief detour in infinity

The infinity is a concept that attracts and fascinate humans from its earlist time. The earliest mathematical account of infinity comes from Zeno of Elea (490-430 BCE) who was a pre-Socratic Greek philosopher of southern Italy (named by Aristotle the "invector of dialectic"). But in order to have a systematic and mathematically rigorouse use of the concept of infinity we have to wait the 17th century, when an English mathematician, Jonh Wallis for the first time used the symbol to denote an infinite quantity in its attempt to divide a region in infinitesimal parts . Than, thanks to his concepts of infinity and infinitesimal,  Leibniz was able to develop big part of his work on calculus, but they were still abstract objects,  different from appreciable quantities as finite numbers. But they shared some interesting properties with them (law of continuity,"whatever succeeds for the finite, also succeeds for the infinite").

Cantor set, we begin with a straight line, of length 1 and remove its the middle third and repest the process with the new two pieces over and over again.


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Cellular automata library - CuCCAl

What is it?

A GPGPU CUDA powered cellular automata library , capable of hiding all the complexity behind the GPU programming of classica/complex and macroscopic cellular automata. The aim of this library is to make life easier to researchers that need to write and execute big cellular automata model.

Belousov-Zhabotinsky reaction cellular automaton.

Figure 1. Dewdney's Belousov-Zhabotinsky reaction cellular automaton.

The programmer has only to write the elementary processes that compose the transition function, register the substates and set up the automaton parameters (for example, the number of steps and cellular space size). The Memory management is completely behind the scene, letting the programmer concentrate only on the model he needs to write.

This library is open source. Help make it better!

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Nikolai Kapustin

Nikolai Kapustin is an **autodidact on composing**; he made his first attempt to compose a piano sonata at age of 13. During his conservatory time he composed and played his Op. 1; a Concertino for piano and orchestra. The Op.1 was a jazz piece and turned out to be his first work performed publicly (1957). He also had his own quintet and was a member of Yuri Saulsky’s Big Band.

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