Q–gorenstein Splinter Rings of Characteristic P Are F–regular
نویسنده
چکیده
A Noetherian integral domain R is said to be a splinter if it is a direct summand, as an R–module, of every module–finite extension ring, see [Ma]. In the case that R contains the field of rational numbers, it is easily seen that R is splinter if and only if it is a normal ring, but the notion is more subtle for rings of characteristic p > 0. It is known that F–regular rings of characteristic p are splinters, and Hochster and Huneke showed that the converse is true for locally excellent Gorenstein rings, [HH4]. In this paper we extend their result by showing that Q–Gorenstein splinters are F–regular. Our main theorem is:
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