Fix a holomorphic line bundle ξ over a compact connected Riemann surface X of genus g, with g ≥ 2, and also fix an integer r such that degree(ξ) > r(2g−1). Let Mξ(r) denote the moduli space of stable vector bundles overX of rank r and determinant ξ. The Fourier–Mukai transform, with respect to a Poincaré line bundle on X × J(X), of any F ∈Mξ(r) is a stable vector bundle on J(X). This gives an e...

Why should a number theorist be interested in algebraic geometry? In this course we hope to demonstrate one very good reason, by showing essentially geometric reasons why certain Diophantine equations fail to have solutions. But we will begin by placing the study of Diophantine equations into the context of algebraic geometry, to see how techniques from many different realms of mathematics can ...

The antenna is an important element of radiocommunication, remote sensing and radiolocalisation systems. The measurement of the antenna radiation pattern characteristics allows one to verify the conformity of the antenna. The simplest measurement method consists in the direct far-field measurement. For large antennas, the necessary measurement distance raises a problem which was resolved by the...

In their paper on the gamma conjecture in mirror symmetry, Golyshev and Zagier introduce what we refer to as Frobenius constants associated an ordinary linear differential operator L with a reflection type singularity. These numbers describe variation around point of solutions defined near other singular points. show that certain geometric cases are periods, they raise question quite generally ...

Let P be the Prym variety associated with a covering π : Y → X between non-singular irreducible projective curves. If P̃ is a principally polarized Prym-Tyurin variety associated with P , we prove that the induced Abel-Prym morphism ρ̃ : Y → P̃ is birational onto its image for genus gX > 2 and deg π 6= 2. We use such result to prove that the Picard bundle over the Prym variety is simple and moreov...

Non-linear magnetic problems are commonly solved by iterative methods. This paper discusses the application of the Picard-method and the Newton-method in the context of solving time-harmonic problems. It is shown that the overall computation time can be decreased by initiating the non-linear solution process using Picard-iterations and by switching to Newton-iterations as soon as an estimator i...

Picard groups of tensor categories play an important role in rational conformal field theory. The Picard group of the representation category C of a rational vertex algebra can be used to construct examples of (symmetric special) Frobenius algebras in C. Such an algebra A encodes all data needed to ensure the existence of correlators of a local conformal field theory. The Picard group of the ca...

In dimension d, Q-factorial Gorenstein toric Fano varieties with Picard number ρX correspond to simplicial reflexive polytopes with ρX+d vertices. Casagrande showed that any d-dimensional simplicial reflexive polytope has at most 3d vertices, if d is even, respectively, 3d − 1, if d is odd. Moreover, for d even there is up to unimodular equivalence only one such polytope with 3d vertices, corre...

Recently Bai and Yang in [On HSS-based iteration methods for weakly nonlinear systems, Appl. Numer. Math. 59 (2009) 2923–2936.] proposed the Picard-HSS iteration method to solve the system of nonlinear equations Ax = φ(x), where A ∈ Cn×n is a nonHermitian positive definite matrix and φ : D ⊂ C → C is continuously differentiable function defined on the open complex domain D in the n-dimensional ...

We consider diagonal cubic surfaces defined by an equation of the form ax + by + cz + dt = 0. Numerically, one can find all rational points of height 6 B for B in the range of up to 10 , thanks to a program due to D. J. Bernstein. On the other hand, there are precise conjectures concerning the constants in the asymptotics of rational points of bounded height due to Manin, Batyrev and the author...