Backward problem for a degenerate viscous Hamilton-Jacobi equation: stability and numerical identification

This paper establishes conditional stability for the backward problem of degenerate viscous Hamilton-Jacobi equations with general non-quadratic Hamiltonians using Carleman estimates and linearization, and proposes numerical identification algorithms based on the adjoint state method and Van Cittert iteration, validated by numerical tests.

S. E. Chorfi, A. Habbal, M. Jahid, L. Maniar, A. RatnaniWed, 11 Ma🔢 math

Identification of a Point Source in the Heat Equation from Sparse Boundary Measurements

This paper establishes the unique recovery of the location and time-dependent amplitude of a point source in the heat equation from sparse boundary flux measurements on unit balls in higher dimensions and simply connected smooth domains in two dimensions, utilizing a combination of spectral analysis, kernel properties, and complex analysis, and validates these theoretical findings through numerical experiments.

Fangyu Gong, Bangti Jin, Yavar Kian, Sizhe LiuWed, 11 Ma🔢 math

Stability Estimates for the Inverse Problem of Reconstructing Point sources in Parabolic Equations

This paper establishes stability estimates for reconstructing the locations and time-dependent amplitudes of point sources in parabolic equations with non-self-adjoint elliptic operators from boundary observations, utilizing a novel combination of Carleman estimates, solution regularity, and explicit adjoint constructions across various spatial dimensions, supported by numerical reconstructions.

Kuang Huang, Bangti Jin, Yavar Kian, Faouzi TrikiWed, 11 Ma🔢 math

On the Mathematical Analysis and Physical Implications of the Principle of Minimum Pressure Gradient

This paper establishes a rigorous two-way equivalence between the incompressible Navier-Stokes equations and the principle of minimum pressure gradient (PMPG), demonstrating that the former is mathematically identical to the instantaneous minimization of the pressure force required to enforce incompressibility, thereby offering a variational framework that generalizes classical Galerkin projections and provides new insights into flow stability and the vanishing-viscosity limit.

Haithem TahaWed, 11 Ma🔢 math-ph

Spherically symmetric solutions to the Einstein-scalar field conformal constraint equations

This paper resolves the Einstein-scalar field conformal constraint equations under spherically symmetric and harmonic assumptions, revealing that while solutions on compact manifolds like the sphere exhibit nonexistence and instability in near-CMC regimes, the equations are always solvable on Euclidean and hyperbolic manifolds, thereby supporting the conformal method's utility for asymptotically flat and hyperbolic initial data.

Philippe Castillon, Cang Nguyen-TheWed, 11 Ma⚛️ gr-qc

On uniqueness of radial potentials for given Dirichlet spectra with distinct angular momenta

This paper establishes the uniqueness of singular radial potentials in Schrödinger operators by proving that infinitely many Dirichlet spectra satisfying a Müntz-type condition determine the potential globally, while two spectra from specific distinct angular momenta ensure local uniqueness near the zero potential, thereby refining previous results and confirming a conjecture by Rundell and Sacks.

Damien Gobin, Benoît Grébert, Bernard Helffer, François NicoleauWed, 11 Ma🔢 math-ph

Linearized Boundary Control Method for Damping Reconstruction in an Acoustic Inverse Boundary Value Problem

This paper develops a linearized boundary control method to reconstruct unknown damping perturbations in the damped wave equation from the linearized Neumann-to-Dirichlet map, providing stability estimates and a validated numerical algorithm for constant backgrounds in any dimension while establishing increasing stability for non-constant backgrounds in dimensions three and higher.

Tianyu Yang, Yang YangWed, 11 Ma🔢 math