منابع مشابه
Deformation of F-purity and F-regularity
For a Noetherian local domain (R, m, K), it is an open question whether strong F–regularity deforms. We provide an affirmative answer to this question when the canonical module satisfies certain additional assumptions. The techniques used here involve passing to a Gorenstein ring, using an anti– canonical cover.
متن کاملGood filtrations and F -purity of invariant subrings
Let k be an algebraically closed field of positive characteristic, G a reductive group over k, and V a finite dimensional G-module. Let B be a Borel subgroup of G, and U its unipotent radical. We prove that if S = SymV has a good filtration, then SU is F -pure. Throughout this paper, p denotes a prime number. Let k be an algebraically closed field of characteristic p, and G a reductive group ov...
متن کاملFailure of F-purity and F-regularity in Certain Rings of Invariants
Let Fq be a finite field of characteristic p, K a field containing it, and R = K[X1, . . . , Xn] a polynomial ring in n variables. The general linear group GLn(Fq) has natural action on R by degree preserving ring automorphisms. L. E. Dickson showed that the subring of elements which are fixed by this group action is a polynomial ring, [Di], though for an arbitrary subgroupG of GLn(Fq), the str...
متن کاملScalable fabrication of high purity diamond nanocrystals with long-spin-coherence nitrogen vacancy centers.
The combination of long spin coherence time and nanoscale size has made nitrogen vacancy (NV) centers in nanodiamonds the subject of much interest for quantum information and sensing applications. However, currently available high-pressure high-temperature (HPHT) nanodiamonds have a high concentration of paramagnetic impurities that limit their spin coherence time to the order of microseconds, ...
متن کاملFirst-principles optical spectra for F centers in MgO.
The study of the oxygen vacancy (F center) in MgO has been aggravated by the fact that the positively charged and the neutral vacancy (F+ and F0, respectively) absorb at practically identical energies. Here we apply many-body perturbation theory in the G0W0 approximation and the Bethe-Salpeter approach to calculate the optical absorption and emission spectrum of the oxygen vacancy in all three ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Mathematische Zeitschrift
سال: 2009
ISSN: 0025-5874,1432-1823
DOI: 10.1007/s00209-009-0536-5