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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

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Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

C-ORM: docs, API.

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Rotating Universes and Time Traveling

From: "andrew cooke" <andrew@...>

Date: Wed, 8 Feb 2006 07:20:40 -0300 (CLST)

A good introductory article on Godel Universes -
http://www.ettnet.se/~egils/essay/essay.html

 In 1949 Kurt Gödel found a cosmological solution to Einstein's field
 equations with rotating matter. The lesson to be learnt from that is
 that the relation between galaxies and the inertial system is more
 intricate than common-sense believes. Mach's principle is only poorly
 incorporated in Einstein's theory.

 [...]

 Gödel's universe has another property that is perhaps even more shocking:
 It allows traveling backwards in time (although the practical difficulties
 would be more than overwhelming). You enter a rocket, and you take a
 journey in the universe along a certain path. Then you will - after many
 billions of years - return to the starting point before you started.

Andrew

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