Schatten class Hankel and $$\overline{\partial }$$ ∂ ¯ -Neumann operators on pseudoconvex domains in $$\mathbb {C}^{n}$$ C n

Monatshefte für Mathematik - Let $$\Omega $$ be a $$C^2$$ -smooth bounded pseudoconvex domain in $$\mathbb {C}^n$$ for $$n\ge 2$$ and let $$\varphi $$ be a holomorphic function on $$\Omega $$...     

The Iwasawa invariant $$\mu$$ μ vanishes for $$\mathbb{Z}_{2}$$ Z 2 -extensions of certain real biquadratic fields

Acta Mathematica Hungarica - For a real biquadratic field, we denote by $$\lambda$$ , $$\mu$$ and $$\nu$$ the Iwasawa invariants of cyclotomic $$\mathbb{Z}_{2}$$ -extension of $$k$$ . We give...     

Projective Compactification of $$\mathbb {R}^{1,1}$$ and Its Möbius Geometry

We examine the semi-Riemannian manifold \(\mathbb {R}^{1,1}\), which is realized as the split complex plane, and its conformal compactification as an analogue of the complex plane and the Riemann sphere. We also consider conformal maps on the compactification and study some of their basic properties.     

Poincaré polynomial of the space $$\overline {{M_{0,n}}} \left( \mathbb{C} \right)$$ and the number of points of the space $$\overline {{M_{0,n}}} \left( {{F_q}} \right)$$M0,n¯(Fq)

A combinatorial proof that the number of points of the space \(\overline {{M_{0,n}}} \left( {{F_q}} \right)\) satisfies the recurrent formula for the Poincaré polynomials of the space \(\overline {{M_{0,n}}} \left( \mathbb{C} \right)\) is obtained.     

Pencils of quadrics and Gromov–Witten–Welschinger invariants of $$\mathbb {C}P^3$$

We establish a formula for the Gromov–Witten–Welschinger invariants of \(\mathbb {C}P^3\) with mixed real and conjugate point constraints. The method is based on a suggestion by J. Kollár that, considering pencils of quadrics, some real and complex enumerative invariants of \(\mathbb {C}P^3\) could be computed in terms of enumerative invariants of \(\mathbb {C}P^1\times \mathbb {C}P^1\) and of elliptic curves.     

Residue codes of extremal Type II \mathbb{Z }_4-codes and the moonshine vertex operator algebra

In this paper, we study the residue codes of extremal Type II $\mathbb{Z }_4$ -codes of length 24 and their relations to the famous moonshine vertex operator algebra (VOA). The main result is a complete classification of all residue codes of extremal Type II $\mathbb{Z }_4$ -codes of length 24. Some corresponding results associated to the moonshine VOA are also discussed.     

Strict comparison and $$ \mathcal{Z} $$-absorption of nuclear C∗-algebras

For any unital separable simple infinite-dimensional nuclear C ^∗-algebra with finitely many extremal traces, we prove that -absorption, strict comparison and property (SI) are equivalent. We also show that any unital separable simple nuclear C ^∗-algebra with tracial rank zero is approximately divisible, and hence is -absorbing.     

On $$\mathbb {R}$$-Linear Problem and Truncated Wiener–Hopf Equation

Siberian Advances in Mathematics - We consider the $$\mathbb {R}$$-linear problem (also known as the Markushevich problem and the generalized Riemann boundary value problem) and the convolution...     

Schiffer’s Problem and an Isoperimetric Inequality for the First Buckling Eigenvalue of Domains on $$\mathbb{S}^{2}$$

We consider the overdetermined eigenvalue problem on a sufficiently regular connected open domain Ω on the 2-sphere :

Bavrin’s Type Factorization of the Temljakov Operator for Holomorphic Functions in Circular Domains of $$\mathbb {C}^{n}$$

The paper concerns investigations of holomorphic functions of several complex variables with a factorization of their Temljakov transform. Firstly, there were considered some inclusions between the families \(\mathcal {C}_{\mathcal {G}},\mathcal {M}_{\mathcal {G}},\mathcal {N}_{\mathcal {G}},\mathcal {R}_{\mathcal {G}},\mathcal {V}_{\mathcal {G}}\) of such holomorphic functions on complete n-circular domain \(\mathcal {G}\) of \(\mathbb {C}^{n}\) in some papers of Bavrin, Fukui, Higuchi, Michiwaki. A motivation of our investigations is a condensation of the mentioned inclusions by some new families of Bavrin’s type. Hence we consider some families \(\mathcal {K}_{ \mathcal {G}}^{k},k\ge 2,\) of holomorphic functions f :  \(\mathcal {G}\rightarrow \mathbb {C},f(0)=1,\) defined also by a factorization of \( \mathcal {L}f\) onto factors from \(\mathcal {C}_{\mathcal {G}}\) and \(\mathcal {M} _{\mathcal {G}}.\) We present some interesting properties and extremal problems on \(\mathcal {K}_{\mathcal {G}}^{k}\).     

Parallel and semi-parallel hypersurfaces of \mathbb{S}^n × ℝ

We give a complete classification of totally umbilical, parallel and semi-parallel hypersurfaces of the Riemannian product space × ℝ. The author is a postdoctoral researcher supported by the Research Foundation — Flanders (F.W.O.).     

Blowup relations on $$mathbb{C}^2/mathbb{Z}_2$$ from Nakajima–Yoshioka blowup relations

Theoretical and Mathematical Physics - Using an elementary algebraic approach, from the Nakajima–Yoshioka blowup relations, we obtain bilinear relations for the Nekrasov partition functions...     

Equidistribution of saddle periodic points for Hénon-type automorphisms of $$\mathbb {C}^k$$

In this paper, we prove the equidistribution of saddle periodic points for Hénon-type automorphisms of \(\mathbb {C}^k\) with respect to its equilibrium measure. A general strategy to obtain equidistribution properties in any dimension is presented. It is based on our recent theory of densities for positive closed currents. Several fine properties of dynamical currents are also proved.     

Vojta’s conjecture on blowups of $${\mathbb{P}^n}$$, greatest common divisors,and the abc conjecture

We will prove some cases of Vojta’s conjecture on blowups of \({\mathbb{P}^n}\), using Schmidt’s subspace theorem. The results can be stated as inequalities of greatest common divisors. Moreover, from Vojta’s conjecture on one further blowup at an infinitely near point, we derive a still-open special case of the abc-conjecture.     

On $$ \mathcal{C} $$*-sets and decompositions of continuous and ηζ-continuous functions

The main purpose of this paper is to introduce the concepts of *-sets, *-continuous functions and to obtain new decompositions of continuous and ηζ-continuous functions. Moreover, properties of *-sets and some properties of -sets are discussed.      

Existence and nonexistence of maximizers for variational problems associated with Trudinger–Moser type inequalities in $${mathbb{R}^N}$$

We discuss the existence of a maximizer for a maximizing problem associated with the Trudinger–Moser type inequality in mathbbR^N(N 3 2){mathbb{R}^N(Ngeq 2)}. Different from the bounded domain case, we obtain both of the existence and the nonexistence results. The proof requires a careful estimate of the maximizing level with the aid of normalized vanishing sequences.     

On the average number of subgroups of the group $${\mathbb {Z}}_m \times {\mathbb {Z}}_n$$ Z m × Z n with k-th power sequence

The Ramanujan Journal - Let $$\mathbb {Z}_{n}$$ be the additive group of residue classes modulo n. Let s(m, n) denote the total number of subgroups of the group $$\mathbb {Z}_{m} \times...