Normal forms for definite integer unimodular quadratic forms

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

A normal form for definite quadratic forms over Fq[t]

An efficient algorithm to compute automorphism groups and isometries of definite Fq [t]-lattices for odd q is presented. The algorithm requires several square root computations in Fq2 but no enumeration of orbits having more than eight elements.

متن کامل

Applications of quadratic D-forms to generalized quadratic forms

In this paper, we study generalized quadratic forms over a division algebra with involution of the first kind in characteristic two. For this, we associate to every generalized quadratic from a quadratic form on its underlying vector space. It is shown that this form determines the isotropy behavior and the isometry class of generalized quadratic forms.

متن کامل

On Definite Quadratic Forms, Which Are Not the Sum of Two Definite or Semi-definite Forms

be a positive definite quadratic form with determinant D R and integer coefficients a ;Call it an even form if all a ; ; are even ., an odd form if at least one a ;; is odd . Then Í,, is called non-decomposable, if it cannot be expressed as a sum of two non-negative quadratic forms with integer coefficients . Mordell 1 ) proved that f, can always be decomposed into a sum of five squares of line...

متن کامل

Solving quadratic equations using reduced unimodular quadratic forms

Let Q be an n × n symmetric matrix with integral entries and with detQ = 0, but not necesarily positive definite. We describe a generalized LLL algorithm to reduce this quadratic form. This algorithm either reduces the quadratic form or stops with some isotropic vector. It is proved to run in polynomial time. We also describe an algorithm for the minimization of a ternary quadratic form: when a...

متن کامل

Definite Quadratic Forms over Fq[x]

Let R be a principal ideal domain with quotient field F . An R-lattice is a free R-module of finite rank spanning an inner product space over F . The classification problem asks for a reasonably effective set of criteria to determine when two given R-lattices are isometric; that is, when there is an inner-product preserving isomorphism carrying one lattice onto the other. In this paper R is the...

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: Proceedings of the American Mathematical Society

سال: 1989

ISSN: 0002-9939

DOI: 10.1090/s0002-9939-1989-0976366-6