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In \S8.3 of our paper ``Duality and Flat Base Change on Formal Schemes" some important results concerning localization and preservation of coherence by basic duality functors were based on the false statement that any closed formal subscheme of an open subscheme of the completion $\mathscr P$ of a relative projective space is an open subscheme of a closed formal subscheme of $\mathscr P$. In this note, the said results are provided with solid foundations. [ABSTRACT FROM AUTHOR]

For 80 years, Dyson's rank has been known as the partition statistic that witnesses the first two of Ramanujan's celebrated congruences for the ordinary partition function. In this paper, we show that Dyson's rank actually witnesses families of partition congruences modulo every prime \ell. This comes from an in-depth study of when a "multiplicity-based statistic" is a crank witnessing congruences for the function p\big (n,m\big), which enumerates partitions of n with parts of size at most m. We also show that as the modulus \ell increases, there is an ever-growing collection of distinct multiplicity-based cranks witnessing these same families. [ABSTRACT FROM AUTHOR]

In this paper, we are concerned with the following Schrödinger-Poisson system with nonhomogeneous boundary conditions \begin{equation*} \begin {cases} -\frac {1}{2}\triangle {u}+\phi u =\omega u, & \text {in }\Omega, \\ -\triangle {\phi }=4\pi u^2, & \text {in } \Omega,\\ \phi =h,u=0, & \text {on } \partial \Omega, \end{cases} \end{equation*} where \Omega is a smooth and bounded domain in \mathbb {R}^3, h is a given nonnegative regular function on \partial \Omega and \omega \in \mathbb {R}. By using variational method and bifurcation theory, we obtain the existence of positive solutions to the above system for \omega larger than some positive constant. [ABSTRACT FROM AUTHOR]

In this paper, we first present new representations for several mock theta functions. In view of the sign flips on these identities, some interesting results involving theta functions are established by new Bailey pairs and Watson's _8\phi _7 transformation formula. Moreover, the truncated forms for the theta series identities are also considered. [ABSTRACT FROM AUTHOR]

This paper considers L^1-spaces of covariant functions of characters of normal subgroups. Assume that G is a locally compact group with the group algebra L^1(G) and N is a closed and normal subgroup of G. Suppose that \mathbb {T} is the circle group and \xi :N\to \mathbb {T} is a character. We introduce the Banach space L_\xi ^1(G,N) of covariant functions of \xi on G and present an operator theoretic approach to study structure of L^1_\xi (G,N). It is proven that L^1_\xi (G,N) and a quotient space of L^1(G) are isometrically isomorphic. The paper is concluded by constructive characterizations for covariant functions of \xi. [ABSTRACT FROM AUTHOR]

Global transfer systems are equivalent to global N_\infty-operads, which parametrize different levels of commutativity in globally equivariant homotopy theory, where objects have compatible actions by all compact Lie groups. In this paper we explicitly describe and completely classify global transfer systems for the family of all abelian compact Lie groups. [ABSTRACT FROM AUTHOR]

In this paper, we prove that there exists a unique weak solution to the Neumann boundary value problem for second order elliptic operators whose coefficients are signed measures. We will give a probabilistic representation of the solution. The heat kernel estimates and reflected diffusion processes play important roles. [ABSTRACT FROM AUTHOR]

In this paper, we study the Landis-type conjecture, i.e., unique continuation property from infinity, of the fractional Schrödinger equation with drift and potential terms. We show that if any solution of the equation decays at a certain exponential rate, then it must be trivial. The main ingredients of our proof are the Caffarelli-Silvestre extension and Armitage's Liouville-type theorem. [ABSTRACT FROM AUTHOR]

Let \Lambda (f) = K[x][y; f\frac {d}{dx} ] be an Ore extension of a polynomial algebra K[x] over a field K of characteristic zero where f\in K[x]. For a given polynomial f, the automorphism group of the algebra \Lambda (f) is explicitly described. The polynomial case \Lambda (0) = K[x,y] and the case of the Weyl algebra A_1= K[x][y; \frac {d}{dx} ] were done by Jung [J. Reine Angew. Math. 184 (1942), pp. 161–174] and van der Kulk [Nieuw Arch. Wisk. (3) 1 (1953), pp. 33–41], and Dixmier [Bul. Soc. Math. France 96 (1968), pp. 209–242], respectively. Alev and Dumas [Comm. Algebra 25 (1997), pp. 1655–1672] proved that the algebras \Lambda (f) and \Lambda (g) are isomorphic iff g(x) = \lambda f(\alpha x+\beta) for some \lambda, \alpha \in K\backslash \{ 0\} and \beta \in K. Benkart, Lopes and Ondrus [Trans. Amer. Math. Soc. 367 (2015), pp. 1993–2021] gave a complete description of the set of automorphism groups of algebras \Lambda (f). In this paper we complete the picture, i.e. given the polynomial f we have the explicit description of the automorphism group of \Lambda (f). The key concepts in finding the automorphism groups are the eigenform, the eigenroot and the eigengroup of a polynomial (introduced in the paper; they are of independent interest). [ABSTRACT FROM AUTHOR]

In this short paper, we prove that the solution of the cubic fourth-order Schrödinger equation (4NLS) on \mathbb {R}^d (5 \leq d \leq 8) enjoys the same decay property as its linear solution does. This result is proved via a bootstrap argument based on the corresponding global result by Pausader [J. Funct. Anal. 256 (2009), pp. 2473–2517]. This result can be extended to more general dispersive equations (including some more 4NLS models) with scattering asymptotics. [ABSTRACT FROM AUTHOR]

The Fueter theorem provides a two step procedure to build an axially monogenic function, i.e. a null-solution of the Cauchy-Riemann operator in \mathbb {R}^4, denoted by \mathcal {D}. In the first step a holomorphic function is extended to a slice hyperholomorphic function, by means of the so-called slice operator. In the second step a monogenic function is built by applying the Laplace operator \Delta in four real variables to the slice hyperholomorphic function. In this paper we use the factorization of the Laplace operator, i.e. \Delta = \mathcal {\overline {D}} \mathcal {D} to split the previous procedure. From this splitting we get a class of functions that lies between the set of slice hyperholomorphic functions and the set of axially monogenic functions: the set of axially polyanalytic functions of order 2, i.e. null-solutions of \mathcal {D}^2. We show an integral representation formula for this kind of functions. The formula obtained is fundamental to define the associated functional calculus on the S-spectrum. [ABSTRACT FROM AUTHOR]

This paper is devoted to the isochronicity of two kinds of planar piecewise polynomial potential systems separated by x-axis and y-axis, respectively. By means of the expansion of the period function near the infinity, we obtain in this paper that for these two cases, the piecewise potential system has an isochronous center at the origin if and only if the subsystems are linear. It is however not true in the analytic scenario; one can find in the paper by F. Mañosas and P. J. Torres [Proc. Amer. Math. Soc. 133 (2005), pp. 3027–3035] that the isochronicity of the center of the piecewise analytic potential system cannot imply the linearity of the two subsystems. [ABSTRACT FROM AUTHOR]

Concerns have been voiced about the correctness of certain technical points in DiPerna's paper (Comm. Math. Phys. \textbf{91} (1983), 1--30) related to the vacuum state. In this note, we provide clarifications. Our conclusion is that these concerns mainly arise from the statement of a lemma for constructing the viscous approximate solutions and some typos; however, the gap can be either fixed by correcting the statement of the lemma and the typos or bypassed by employing the finite difference methods. [ABSTRACT FROM AUTHOR]

In this paper, we establish the method of holomorphic handle attaching to the strongly pseudoconcave boundary of a complex surface. We use this for proving the following statements: (1) every closed connected oriented contact 3-manifold can be filled as the strongly pseudoconcave boundary of a compact complex surface; (2) any two non-empty closed connected oriented contact 3-manifolds are complex cobordant. Moreover, we show that such a complex surface (or complex cobordism) can be taken Kähler. [ABSTRACT FROM AUTHOR]

Let S be the polynomial ring on the space of non-square generic matrices or the space of odd-sized skew-symmetric matrices, and let I be the determinantal ideal of maximal minors or Pf the ideal of sub-maximal Pfaffians, respectively. Using desingularizations and representation theory of the general linear group we expand upon work of Raicu–Weyman–Witt [Adv. Math. 250 (2014), pp. 596–610] to determine the S-module structures of Ext^j_S(S/I^t, S) and Ext^j_S(S/Pf^t, S), from which we get the degrees of generators of these Ext modules. As a consequence, via graded local duality we answer a question of Wenliang Zhang [J. Pure Appl. Algebra 225 (2021), Paper No. 106789] on the socle degrees of local cohomology modules of the form H^j_\mathfrak {m}(S/I^t). [ABSTRACT FROM AUTHOR]

The aim of this paper is to show that the structure skew brace associated with a finite non-degenerate solution of the Yang-Baxter equation is finitely presented. [ABSTRACT FROM AUTHOR]

Given a non-positive DG-ring A, associated to it are the reduction and coreduction functors F(-) = \mathrm {H}^0(A)\otimes ^{\mathrm {L}}_A - and G(-) = \mathrm {R}\operatorname {Hom}_A(\mathrm {H}^0(A),-), considered as functors \operatorname {\mathsf {D}}(A) \to \operatorname {\mathsf {D}}(\mathrm {H}^0(A)), as well as the forgetful functor S:\operatorname {\mathsf {D}}(\mathrm {H}^0(A)) \to \operatorname {\mathsf {D}}(A). In this paper we carry a systematic study of the categorical properties of these functors. As an application, a new descent result for vanishing of \operatorname {Ext} and \operatorname {Tor} over ordinary commutative noetherian rings is deduced. [ABSTRACT FROM AUTHOR]

Disjoint sequence methods from the theory of Riesz spaces are used to study measures of weak non-compactness in L_{1}(\mu)-spaces. A principal new result of the present paper is the following: Let E be an abstract M-space. Then \begin{align*} \omega (B)&=\sup \{\limsup \limits _{n\rightarrow \infty }\rho _{B}(x_{n}):(x_{n})_{n}\subseteq B_{E} \operatorname {disjoint} \}\\ &=\inf \{\varepsilon >0:\exists x^{*}\in E^{*}_{+} \operatorname {so}\operatorname {that} B\subseteq [-x^{*},x^{*}]+\varepsilon B_{E^{*}}\}\\ &=\sup \{\limsup \limits _{n\rightarrow \infty }\rho _{B}(x_{n}):(x_{n})_{n}\subseteq B_{E} \operatorname {weakly}\operatorname {null} \}\\ &=\sup \{\operatorname {ca}_{\rho _{B}}((x_{n})_{n}):(x_{n})_{n}\subseteq (B_{E})_{+} \operatorname {increasing} \}\\ &=\sup \{\limsup \limits _{n\rightarrow \infty }\|x^{*}_{n}\|:(x^{*}_{n})_{n}\subseteq \operatorname {Sol}(B)\operatorname {disjoint}\}\\ &=\sup \{\limsup \limits _{n\rightarrow \infty }\sup \limits _{x^{*}\in B}|\langle x^{*},x_{n}\rangle |:(x_{n})_{n}\subseteq B_{E}\operatorname {disjoint} \}\\ \end{align*} for every norm bounded subset B of E^{*}. [ABSTRACT FROM AUTHOR]

The hyperbolic structure on a 3–dimensional cone–manifold with a knot as singularity can often be deformed into a limiting Euclidean structure. In the present paper we show that the respective normalised Euclidean volume is always an algebraic number, which is reminiscent of Sabitov's theorem (the Bellows Conjecture). This fact also stands in contrast to hyperbolic volumes whose number–theoretic nature is usually quite complicated. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the global asymptotic stability of an age-structured population dynamics model with a Ricker's type of birth function. This model is a hyperbolic partial differential equation with a nonlinear and nonlocal boundary condition. We prove a uniform persistence result for the semiflow generated by this model. We obtain the existence of global attractors and we prove the global asymptotic stability of the positive equilibrium by using a suitable Lyapunov functional. Furthermore, we prove that our global asymptotic stability result is sharp, in the sense that Hopf bifurcation may occur as close as we want from the region global stability in the space of parameter. [ABSTRACT FROM AUTHOR]

In a recent series of important works Wei-Zhang [Adv. Math. 380 (2021), Paper No. 107606, 45; Proc. Lond. Math. Soc. (3) 124 (2022), pp. 106–131; Laplacian vanishing theorem for quantized singular Liouville equation , Preprint, arXiv:2202.10825, 2022] proved several vanishing theorems for non-simple blow-up solutions of singular Liouville equations. It is well known that a non-simple blow-up situation happens when the spherical Harnack inequality is violated near a quantized singular source. In this article, we further strengthen the conclusions of Wei-Zhang by proving that if the spherical Harnack inequality does hold, there exist blow-up solutions with non-vanishing coefficient functions. [ABSTRACT FROM AUTHOR]

Upper triangular, and more generally, block-triangular matrices, are rather important in Linear Algebra, and also in Ring theory, namely in the theory of PI algebras (algebras that satisfy polynomial identities). The group gradings on such algebras have been extensively studied during the last decades. In this paper we prove that for any group grading on a block-triangular matrix algebra, over an arbitrary field, the Jacobson radical is a graded (homogeneous) ideal. As noted by F. Yasumura [Arch. Math. (Basel) 110 (2018), pp. 327–332] this yields the classification of the group gradings on these algebras and confirms a conjecture made by A. Valenti and M. Zaicev [Arch. Math. (Basel) 89 (2007), pp. 33–40]. [ABSTRACT FROM AUTHOR]

It is well-known that the research of linear combination of composition operators has become a topic of increasing interest. Recently, Choe, Koo and Wang proved that the compactness of combinations composition operators induced by the symbols satisfying the condition (CNC) implies that each difference is compact on the weighted Bergman space. Motivated by that work, in this paper, we discuss which difference is compact on the weighted Bergman space when the coefficients do not satisfy the condition (CNC). [ABSTRACT FROM AUTHOR]

In this paper, we give the affirmative answer to a long-standing open problem of Reich in fixed point theory following the restatement of Jachymski. [ABSTRACT FROM AUTHOR]

In this paper, we will compute the non-abelian cohomology of the universal complete curve in positive characteristic. This extends Hain's result on the non-abelian cohomology of generic curves in characteristic zero to positive characteristics. Furthermore, we will prove that the exact sequence of etale fundamental groups of the universal n-punctured curve in positive characteristic does not split. [ABSTRACT FROM AUTHOR]

The intrinsic square functions including the Lusin area function, Littlewood-Paley g-function and g^\ast _\lambda-function dominate pointwisely the classical Littlewood-Paley functions and can be used to characterize the weighted Hardy spaces and more general Musielak-Orlicz Hardy spaces etc. This paper shows that for b\in \mathrm {BMO(\mathbb {R}^n)}, the commutators generated by these intrinsic square functions with b are bounded from H^p_\omega (\mathbb {R}^n) to L^p_\omega (\mathbb {R}^n) for some 0

Let \mathcal M be a semifinite factor with a faithful normal semifinite tracial weight \tau, and \mathscr P the set of all projections in \mathcal M. Denote by \mathscr P_{c} the Grassmann space of all projections in \mathscr P with trace c, where c is a positive real number. A map \psi : \mathscr P_c\rightarrow \mathscr P_c is called an ortho-isomorphism if \psi is a bijection of \mathscr P_c onto \mathscr P_c satisfying, for all P,Q\in \mathscr P_c, P\perp Q if and only if \psi (P)\perp \psi (Q). The aim of this paper is to establish a version of Uhlhorn's theorem in the setting of semifinite factors. We give a complete characterization of ortho-isomorphisms on Grassmann space \mathscr P_c in a semifinite factor. And we show that an ortho-isomorphism \psi : \mathscr P_c\rightarrow \mathscr P_c can be extended to a Jordan *-isomorphism \rho of \mathcal M onto \mathcal M. As an application, we obtain the structure of surjective isometries on \mathscr P_c with respect to strictly increasing unitarily invariant norms. [ABSTRACT FROM AUTHOR]

This paper is concerned with a class of finite time collapsing rate along Kähler-Ricci flow on projective bundles. It is shown that the diameter of the fibers tend to zero at the rate (T-t)^{\frac {1}{2}-\epsilon } for any \epsilon >0 as t approaches the singular time T. [ABSTRACT FROM AUTHOR]

This paper deals with the chaotic behavior of linear operators on Banach spaces in both discrete and continuous cases. The inheritances of chaos for linear operators and C_0-semigroups are obtained. More precisely, for any positive integer n\geq 2, both Li-Yorke n-chaos and distributional n-chaos are proved to be inherited under iterations for a linear operator. One further shows that a C_0-semigroup \{T_t\}_{t\geq 0} and every single operator T_t share the same Li-Yorke n-scrambled set and distributionally n-scrambled set for any positive integer n\geq 2. In particular, the Li-Yorke n-chaos and distributional n-chaos become the Li-Yorke chaos and distributional chaos when n=2, respectively. Some equivalent criteria for dense n-chaos and generic n-chaos of linear operators and C_0-semigroups are also established for any n\geq 2. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic behavior of the smallest eigenvalue \lambda _N, of the (N+1)\times (N+1) Hankel matrix \mathcal {M}_N=(\mu _{j+k})_{0\le j,k\le N} generated by the semi-classical Hermite weight w(z,t)=|z|^\lambda \exp \left (-z^2+tz\right), z, t \in \mathbb {R}, \lambda >-1. An asymptotic expression of the orthonormal polynomials \mathcal {P}_N(z) with the semi-classical Hermite weight w(z,t) is established as N tends to infinity. Based on the orthonormal polynomials \mathcal {P}_N(z), we obtain the specific asymptotic formulas of \lambda _{N}. [ABSTRACT FROM AUTHOR]

In this paper, by using an integral representation of Ismail and Kelker for the quotient of Tricomi hypergeometric functions, we investigate the infinite divisibility and self-decomposability of the recently defined four-parameter lifetime Whittaker distribution, which is a natural extension of the classical gamma, exponential, chi-square, generalized Lindley, Lindley, beta prime, and Lomax distributions. We also show that the Whittaker distribution belongs to the class of hyperbolically completely monotone distributions and generalized gamma convolutions, and it is a super-Gaussian distribution. By using some results for the moments of the Whittaker distribution, we also deduce some Turán type inequalities for the Whittaker functions of the second kind and as an application we show that the effective variance of the Whittaker distribution is bounded from below. [ABSTRACT FROM AUTHOR]

In this paper, we study the rigidity results of complete graphical translating hypersurfaces when the translating direction is not in the graphical direction. We proved that any entire graphical translating surface in the translating direction not parallel to the graphical one is flat if either the translating surface is mean convex or the entropy of the translating surface is smaller than 2. For higher dimensional case, we show that the same conclusion holds if the graphical translating hypersurface satisfies certain growth condition. [ABSTRACT FROM AUTHOR]