Results 11 to 20 of about 50 (49)
Geodesics in the space of relatively Kähler metrics
Abstract We derive the geodesic equation for relatively Kähler metrics on fibrations and prove that any two such metrics with fibrewise constant scalar curvature are joined by a unique smooth geodesic. We then show convexity of the log‐norm functional for this setting along geodesics, which yields simple proofs of Dervan and Sektnan's uniqueness result
Michael Hallam
wiley +1 more source
Degenerate nonlinear parabolic equations with discontinuous diffusion coefficients
Abstract This paper is devoted to the study of some nonlinear parabolic equations with discontinuous diffusion intensities. Such problems appear naturally in physical and biological models. Our analysis is based on variational techniques and in particular on gradient flows in the space of probability measures equipped with the distance arising in the ...
Dohyun Kwon, Alpár Richárd Mészáros
wiley +1 more source
Three ways to solve partial differential equations with neural networks — A review
Abstract Neural networks are increasingly used to construct numerical solution methods for partial differential equations. In this expository review, we introduce and contrast three important recent approaches attractive in their simplicity and their suitability for high‐dimensional problems: physics‐informed neural networks, methods based on the ...
Jan Blechschmidt, Oliver G. Ernst
wiley +1 more source
Error estimation for second‐order partial differential equations in nonvariational form
Abstract Second‐order partial differential equations (PDEs) in nondivergence form are considered. Equations of this kind typically arise as subproblems for the solution of Hamilton–Jacobi–Bellman equations in the context of stochastic optimal control, or as the linearization of fully nonlinear second‐order PDEs. The nondivergence form in these problems
Jan Blechschmidt +2 more
wiley +1 more source
Canonical complex extensions of Kähler manifolds
Abstract Given a complex manifold X, any Kähler class defines an affine bundle over X, and any Kähler form in the given class defines a totally real embedding of X into this affine bundle. We formulate conditions under which the affine bundles arising this way are Stein and relate this question to other natural positivity conditions on the tangent ...
Daniel Greb, Michael Lennox Wong
wiley +1 more source
Simplified Geometric Approach to Freeform Beam Shaper Design
Beam of light shaping process can be considered ultimate, if both irradiance and wavefront spatial distributions are under control and both can be shaped arbitrarily. In order to keep these two quantities determined simultaneously, it is required to apply at least two powered refractive or reflective surfaces.
Jacek Wojtanowski +2 more
wiley +1 more source
Attractors and Finite‐Dimensional Behaviour in the 2D Navier‐Stokes Equations
The purpose of this review is to give a broad outline of the dynamical systems approach to the two‐dimensional Navier‐Stokes equations. This example has led to much of the theory of infinite‐dimensional dynamical systems, which is now well developed.
James C. Robinson +3 more
wiley +1 more source
The Initial and Neumann Boundary Value Problem for a Class Parabolic Monge‐Ampère Equation
We consider the existence, uniqueness, and asymptotic behavior of a classical solution to the initial and Neumann boundary value problem for a class nonlinear parabolic equation of Monge‐Ampère type. We show that such solution exists for all times and is unique.
Juan Wang +3 more
wiley +1 more source
Viscosity solutions of fully nonlinear functional parabolic PDE
By the technique of coupled solutions, the notion of viscosity solutions is extended to fully nonlinear retarded parabolic equations. Such equations involve many models arising from optimal control theory, economy and finance, biology, and so forth. The comparison principle is shown.
Liu Wei-an, Lu Gang
wiley +1 more source
A Miyaoka–Yau inequality for hyperplane arrangements in CPn$\mathbb {CP}^n$
Abstract Let H$\mathcal {H}$ be a hyperplane arrangement in CPn$\mathbb {CP}^n$. We define a quadratic form Q$Q$ on RH$\mathbb {R}^{\mathcal {H}}$ that is entirely determined by the intersection poset of H$\mathcal {H}$. Using the Bogomolov–Gieseker inequality for parabolic bundles, we show that if a∈RH$\mathbf {a}\in \mathbb {R}^{\mathcal {H}}$ is ...
Martin de Borbon, Dmitri Panov
wiley +1 more source

