On the Mulitplicity of Zeros of Polynomials over Arbitrary Finite Dimensional K-Algebras.
We obtain, in a simple way, an estimate for the Noether exponent of an ideal I without embedded components (i.e. we estimate the smallest number μ such that ).
Motivated by the paper by H. Herrlich, E. Tachtsis (2017) we investigate in ZFC the following compactness question: for which uncountable cardinals , an arbitrary nonempty system of homogeneous -linear equations is nontrivially solvable in provided that each of its subsystems of cardinality less than is nontrivially solvable in ?
It is shown that for any Artinian modules , is the greatest integer such that .
Let be a projective Frobenius split variety with a fixed Frobenius splitting . In this paper we give a sharp uniform bound on the number of subvarieties of which are compatibly Frobenius split with . Similarly, we give a bound on the number of prime -ideals of an -finite -pure local ring. Finally, we also give a bound on the number of log canonical centers of a log canonical pair. This final variant extends a special case of a result of Helmke.
We will prove that the Pierce-Birkhoff Conjecture holds for non-singular two-dimensional affine real algebraic varieties over real closed fields, i.e., if is such a variety, then every piecewise polynomial function on can be written as suprema of infima of polynomial functions on . More precisely, we will give a proof of the so-called Connectedness Conjecture for the coordinate rings of such varieties, which implies the Pierce-Birkhoff Conjecture.
Given integers and a constant , consider the space of -tuples of real polynomials in variables of degree , whose coefficients are in absolute value, and satisfying . We study the family of algebraic functions, where is a polynomial, and being a constant depending only on . The main result is a quantitative extension theorem for these functions which is uniform in . This is used to prove Bernstein-type inequalities which are again uniform with respect to .The proof is based on...