We prove that a bijective linear transformation between von Neumann factors that commute with a λ-Aluthge transform is necessarily a non-zero scalar multiple of an algebra *-isomorphism in the case of algebras that are not of type I2. As for type I2 factors, that is, in the particular case of the algebra of 2 by 2 complex matrices, we also present a complete description of those transforma…

One of the main results of a recent paper by Gross–Tosatti–Zhang establishes estimates on the collapsing of Ricci-flat K¨ahler metrics on holomorphic torus fibrations. We remove a projectivity assumption from these estimates and simplify some of the underlying analysis.

We generalize the Gleason–Kahane–Z˙ elazko theorem to modules. As an application, we show that every linear functional on a Hardy space that is non-zero on the outer functions is a multiple of a point evaluation. A further consequence is that every linear endomorphism of a Hardy space that maps outer functions to nowhere-zero functions is a weighted composition operator. In neither cas…

Recently it was shown by H. Guenancia and M. P˘aun that a singular metric satisfying the conical K¨ahler–Einstein equation with a simple normal crossing divisor is quasi-isometric to a conical metric along that divisor. In this article, we present an alternative proof of their theorem.

Tahun Terbit

2010

Sedimentary deltas forming in the world’s regulated rivers are a glaring gap in our knowledge of dammed riverine ecosystems. Basic ecological information is needed to inform the current debate about whether deltas should be retained and managed to gain ecosystem services lost under reservoirs or whether they should be partially removed to improve flow conveyance and to resupply sediment-starv…

We generalize theorems of Cochran–Lickorish and Owens–Strle to the case of links with more than one component. This enables the use of linking forms on double branched covers, Heegaard Floer correction terms, and Donaldson’s diagonalization theorem to complete the table of unlinking numbers for nonsplit prime links with crossing number nine or less.

Coupled human and natural systems (CHANS) are systems of feedback linking people and ecosystems. A feature of CHANS is that this ecological feedback connects people across time and space. Failing to account for these dynamic links results in intertemporal and spatial externalities, reaping benefits in the present but imposing costs on future and distant people, such as occurs with overgrazing. …

Payments for watershed services (PWS) as a policy tool for enhancing water quality and supply have gained momentum in recent years, but their ability to lead to sustainable watershed outcomes is uncertain. Consequently, the demand for effective monitoring and evaluation (M&E) of PWS impacts on coupled human and natural systems (CHANS) and their implications for watershed sustainability (WS) is …

We describe the spectrum of certain integration operators acting on generalized Fock spaces.