Claudio Maccone (cmaccone@to.alespazio.it)
Rolf Mertig rolfm@nikhefh.nikhef.nl
Computer algebra techniques are used in theoretical physics since the late sixties. Nowadays, with improved hardware and software, more and more non-trivial results, e.g. in perturbation theory, could not have been achieved without the use of computer algebra programs. While for physicists the results and the interpretation of their research is naturally most important it is realized at a larger scale now that computer algebra systems and special-purpose programs written in the corresponding mathematical high-level languages can be extremely useful (and fun) when doing calculationally intensive investigations. This session has as its goal to bring together researchers in theoretical physics who have used computer algebra in a substantial part of their research.
This pro-SETI claim is probably correct as long as one assumes that the only conceivable form of relativistic interstallar flight is the one arising from the special theory of relativity. In fact, the basic assumption of the special theory of relativity is that in no case the speed of light can be exceeded. Surprisingly enough, however, recent advances in the general theory of relativity seem to show that Faster-Than-Light (FTL) travel is possible within the framework of the general theory of relativity. The explanation to this apparent contrast between special and general relativoty lies in the fact that general relativity makes use of non-linear differential equations and non-Euclidean spacetime geometry. This larger mathematical armoury makes room for a whole new class of unexpected relativistic phoenomena to come to light. One such "oddity" of general relativity is the Theory of Worhmoles, that could be more politely called Tunnels into SpaceTime. A neat, mildly-mathematical account of this Theory was given to JBIS readers by Robert Forward (JBIS, Vol. 49 (1989), pages 533-542), and it centers particularly around a paper published in 1987 by Michael S. Morris and Kip S. Thorne, of Caltech. The latter's equations predict that spaceflight between two distant targets, such as between two stars, may be possible in a time of hours if a "tunnel", dug into space-time, exists between the two stars. However, Morris and Thorne also showed that keeping the tunnel open for the spaceship to travel through would require the use of a kind of matter, called "exotic" by them, that does not appear to exist in nature. Thus, the request for exotic matter is a severe constraint to the natural existence or to the artificial making of a Morris-Thorne Wormhole.
This request for "exoticity" is waived in the present paper. We firstly review the mathematics of spaceflight through a Morris-Thorne Wormhole. Then, we show how to adapt to the Morris-Thorne Wormhole a particular exact solution of the Einstein equations that was discovered back in 1917 by Tullio Levi-Civita. The advantage of this new type of Wormhole is that no exotic matter is needed to make it: only a very strong static uniform magnetic field is required. These results might lead to a laboratory experiment aiming at creating a Micro-Magnetic-Wormhole in the lab by virtue of very strong magnetic fields. We finally show that the speed of light at the center of this Micro-Magnetic-Wormhole may slow down up to considerable fractions of c, thus providing a measurable proof of the Wormhole existence.
