It is a starting point in string theory to
assume that elementary particles are in fact rotating strings, and the final
goal of the theory is a complete description of fundamental physics, including
general relativity. This paper is instead concerned with the reversed question:
starting from general relativity, is there a good way to motivate why rotating
strings should be more natural models for elementary particles than, say,
spherical particles or point-particles? Also, the purpose here is not to
motivate full string theory. For example, no hidden dimensions come into play,
only the four usual ones, and strings are defined in a very simple geometric
way. Rather, the focus is on investigating an interesting mathematical
property, which implies that strings may have special features with respect to
rotation which spherically symmetric particles have not. In particular, it
turns out that in a certain sense rotating strings are simpler than
non-rotating ones. This is a consequence of the indefinite metric, and the main
result states that the curvature of a non-rotating string, as measured by the
square of the scalar curvature, may be reduced by letting it rotate in an
appropriate way. The calculations underlying this theorem are heavy and have
partly been carried out using Mathematica, although in principle the essential
theorem may not require super-human labour.
Article by Martin
Tamm,from University of Stockholm, Sweden.
Full access: http://mrw.so/3EV2CT
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| Image by photo fiddler,from Flickr-cc. |
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