Metabolic Involutions and Quadratic Radical Extensions
نویسنده
چکیده
In this paper we characterise involutions that become metabolic over a quadratic field extension attained by adjoining a square root.
منابع مشابه
Metabolic Involutions
In this paper we study the conditions under which an involution becomes metabolic over a quadratic field extension. We characterise those involutions that become metabolic over a given separable quadratic extension. We further give an example of an anisotropic orthogonal involution that becomes isotropic over a separable quadratic extension.
متن کاملCOUNTEREXAMPLES TO A CONJECTURE OF LEMMERMEYER Nigel Boston and Charles Leedham-Green
We produce infinitely many finite 2-groups that do not embed with index 2 in any group generated by involutions. This disproves a conjecture of Lemmermeyer and restricts the possible Galois groups of unramified 2-extensions, Galois over Q, of quadratic number fields.
متن کاملPfister ’ S Theorem for Involutions Of
We use the fact that a projective half-spin representation of Spin 12 has an open orbit to generalize Pfister's result on quadratic forms of dimension 12 in I 3 to orthogonal involutions. In his seminal paper [Pf], Pfister proved strong theorems describing quadratic forms of even dimension ≤ 12 that have trivial discriminant and Clifford invariant, i.e., that are in I 3. His results have been e...
متن کاملDecomposable Quadratic Forms and Involutions
In his book on compositions of quadratic forms, Shapiro asks whether a quadratic form decomposes as a tensor product of quadratic forms when its adjoint involution decomposes as a tensor product of involutions on central simple algebras. We give a positive answer for quadratic forms defined over local or global fields and produce counterexamples over fields of rational fractions in two variable...
متن کاملSome extensions of Darbo's theorem and solutions of integral equations of Hammerstein type
In this brief note, using the technique of measures of noncompactness, we give some extensions of Darbo fixed point theorem. Also we prove an existence result for a quadratic integral equation of Hammerstein type on an unbounded interval in two variables which includes several classes of nonlinear integral equations of Hammerstein type. Furthermore, an example is presented to show the effic...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2011