A closer look at semistability for singular principal bundles
نویسنده
چکیده
We substantially re ne the theory of singular prin ipal bundles introdu ed in a former paper. In parti ular, we show that we need only honest singular prin ipal bundles in our ompa ti ation. These are obje ts whi h arry the stru ture of a rational prin ipal bundle in the sense of Ramanathan. Moreover, we arrive at a mu h simpler semistability ondition. In the ase of a semisimple group, this is just the Gieseker-version of Ramanathan's semistability ondition for the orresponding rational prin ipal G-bundle.
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تاریخ انتشار 2004