Birational positivity in dimension 4

نویسندگان

چکیده

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Matrix positivity preservers in fixed dimension

A celebrated 1942 result of Schoenberg characterizes all entry-wise functions which preserve positivity of matrices of any size. I will present a characterization of polynomials which preserve positivity when applied entry-wise on matrices of a fixed dimension. All put in historical context and motivated by recent demands of statistics of large data and optimization theory. A sketch of the proo...

متن کامل

Pictures of complete positivity in arbitrary dimension

Two fundamental contributions to categorical quantum mechanics are presented. First, we generalize the CP-construction, that turns any dagger compact category into one with completely positive maps, to arbitrary dimension. Second, we axiomatize when a given category is the result of this construction.

متن کامل

Birational Transformations in 4-space and 5-space

The purpose of this paper is to describe certain Cremona transformations in 4-space and S-space, especially the former. The transformations in question are interesting on account of analogies with transformations in ordinary space, because they can be simply expressed and effectively studied by the use of equations, as well as synthetically, and because of the classic nature of the loci involve...

متن کامل

On the birational geometry of toric Fano 4-folds

In this Note, we announce a factorization result for equivariant birational morphisms between toric 4-folds whose source is Fano: such a morphism is always a composite of blow-ups along smooth invariant centers. Moreover, we show with a counterexample that, differently from the 3-dimensional case, even if both source and target are Fano, the intermediate varieties can not be chosen Fano. Sur la...

متن کامل

Birational motives, I: pure birational motives

In the preprint [19], we toyed with birational ideas in three areas of algebraic geometry: plain varieties, pure motives in the sense of Grothendieck, and triangulated motives in the sense of Voevodsky. These three themes are finally treated separately in revised versions. The first one was the object of [21]; the second one is the object of the present paper; we hope to complete the third one ...

متن کامل

ذخیره 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: Annales de l’institut Fourier

سال: 2014

ISSN: 0373-0956,1777-5310

DOI: 10.5802/aif.2845