We present an algorithm to compute the primary decomposition of a submodule N of the free module Z[x1, . . . , xn]. For this purpose we use algorithms for primary decomposition of ideals in the polynomial ring over the integers. The idea is to compute first the minimal associated primes of N , i.e. the minimal associated primes of the ideal Ann(Z[x1, . . . , xn]/N ) in Z[x1, . . . , xn] and the...

Let {f1, f2, . . . , ft} ⊂ Q[z1, . . . , zN ] be a set of homogeneous polynomials. Let Z denote the complex, projective, algebraic set determined by the homogeneous ideal I = (f1, f2, . . . , ft) ⊂ C[z1, . . . , zN ]. Numerical continuation-based methods can be used to produce arbitrary precision numerical approximations of generic points on each irreducible component of Z. Consider the prime d...

It is shown that the exotic non-qqq hadrons of pentaquark qqqqq̄ states can be clearly distinguished from the conventional qqq-baryon resonances or their hybrids if the flavor of q̄ is different from any of the other four quarks. We suggest the physical process p(e, eK)Z(uuuds̄), which can be investigated at the Thomas Jefferson National Accelerator Facility (JLab), as an ideal process to search f...

1.2. Proposition. — π : PnA → SpecA is a closed morphism. Proof. Suppose Z ↪→ PnA is a closed subset. We wish to show that π(Z) is closed. Suppose y / ∈ π(Z) is a closed point of SpecA. We’ll check that there is a distinguished open neighborhood D(f) of y in SpecA such that D(f) doesn’t meet π(Z). (If we could show this for all points of π(Z), we would be done. But I prefer to concentrate on cl...

For a commutative ring R, let Nil(R) be the set of all nilpotent elements of R, Z(R) be the set of all zero divisors of R, T (R) be the total quotient ring of R, and H = {R | R is a commutative ring and Nil(R) is a divided prime ideal of R}. For a ring R ∈ H, let φ : T (R) −→ RNil(R) such that φ(a/b) = a/b for every a ∈ R and b ∈ R\Z(R). A ring R is called a ZPUI ring if every proper ideal of R...

Let R be a commutative ring with nonzero identity, Z(R) be its set of zero-divisors, Nil(R) be its ideal of nilpotent elements, and U(R) be its group of units. We define a nonempty proper subset H of R to be a multiplicative-prime subset of R if the following two conditions hold: (i) ab ∈ H for every a ∈ H and b ∈ R; (ii) if ab ∈ H for a, b ∈ R, then either a ∈ H or b ∈ H . For example, H is mu...

We will denote by 〈γ1, ..., γk〉 the differential ideal generated by γ1, ..., γk, i.e. the set of elements of Ω∗(M) of the form α ∧ γ1 + ...+ α ∧ γk + β ∧ dγ1 + ...+ β ∧ dγk, for some α, ..., α, β, ..., β ∈ Ω∗(M). We also denote by 〈γ1, ..., γk〉alg the “algebraic” ideal (not necessarily closed under d) consisting of elements of the form α ∧ γ1 + ...+ α ∧ γk. The basic problem of EDS is to find i...

1 Introduction. In this paper, two players alternate removing a positive number of counters from one of n piles of counters, and the choice of which pile he removes from can change on each move. On his initial move, the player moving first can remove from one pile of his choice at most t counters. On each subsequent move, a player can remove from one pile of his choice at most f (x) counters, w...

The work of Dixmier in 1977 and Moeglin in 1980 show us that for a prime ideal P in the universal enveloping algebra of a complex finite-dimensional Lie algebra the properties of being primitive, rational and locally closed in the Zariski topology are all equivalent. This equivalence is referred to as the Dixmier-Moeglin equivalence. In this thesis we will study skew Laurent polynomial rings of...

We explicitly construct a large class of unitary transformations that allow to perform the ideal estimation of the phase-shift on a single-mode radiation field. The ideal phase distribution is obtained by heterodyne detection on two radiation modes after the interaction. The quantum estimation of an unknown phase shift—the so called quantum phase measurement—is the essential problem of high sen...