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arXiv · 1304.0226

On distant-isomorphisms of projective lines

Andrea Blunck·Hans Havlicek
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Abstract

We determine all distant-isomorphisms between projective lines over semilocal rings. In particular, for those semisimple rings that do not have a simple component which is isomorphic to a field, every distant isomorphism arises from a Jordan isomorphism of rings and a projectivity. We show this by virtue of a one-one correspondence linking the projective line over a semisimple ring with a Segre product of Grassmann spaces.

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Andrea Blunck, Hans Havlicek. 2013-03-31. On distant-isomorphisms of projective lines. https://doi.org/10.1007/s00010-004-2745-7

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