Mathematics Problem Archive

Showing 1-27 of 27 problems

AMR-019-0001
Partially Solved

Some Open Problems in Elasticity — Existence of minimizers

v1.3 research notes

Prove the existence of energy minimizers for elastostatics for quasiconvex stored-energy functions $W$ satisfying $W(A)\to\infty$ as $\det A\to0^+$ ....

L3
Partial Differential Equations
AMR-019-0002
Open

Some Open Problems in Elasticity — Testing convexity conditions

v1.3 research notes

Find useful ways of verifying polyconvexity and quasiconvexity for stored-energy functions arising in anisotropic nonlinear elasticity....

L3
Partial Differential Equations
AMR-019-0003
Open

Some Open Problems in Elasticity — Regularity of minimizers

v1.3 research notes

Determine when the minimizer $y^*$ in Theorem 2.1 of the source is smooth....

L4
Partial Differential Equations
AMR-019-0004
Partially Solved

Some Open Problems in Elasticity — Lavrentiev phenomena

v1.3 research notes

Can the Lavrentiev phenomenon occur for elastostatics under growth conditions ensuring that all finite-energy deformations are continuous?...

L4
Partial Differential Equations
AMR-019-0005
Partially Solved

Some Open Problems in Elasticity — Weak Euler-Lagrange equations

v1.3 research notes

Prove or disprove that, under reasonable growth conditions on $W$, energy minimizers satisfy the weak Euler-Lagrange equations....

L3
Partial Differential Equations
AMR-019-0006
Open

Some Open Problems in Elasticity — A positive Jacobian bound

v1.3 research notes

Prove or disprove that, under reasonable growth conditions on $W$, an energy-minimizing deformation satisfies $\det Dy^*(x)\ge\varepsilon>0$....

L3
Partial Differential Equations
AMR-019-0007
Partially Solved

Some Open Problems in Elasticity — Smooth self-contact

v1.3 research notes

Justify the Ciarlet-Nečas minimization problem, or an appropriate modification, in situations involving smooth self-contact....

L3
Partial Differential Equations
AMR-019-0008
Partially Solved

Some Open Problems in Elasticity — Uniqueness of equilibrium

v1.3 research notes

Prove or disprove uniqueness of sufficiently smooth equilibrium solutions for pure-displacement problems in homogeneous bodies homeomorphic to a ball ...

L3
Partial Differential Equations
AMR-019-0009
Open

Some Open Problems in Elasticity — Nonglobal local minimizers

v1.3 research notes

Devise general methods for proving the existence of local but nonglobal minimizers and other weak equilibria in nonlinear elastostatics....

L3
Partial Differential Equations
AMR-019-0010
Partially Solved

Some Open Problems in Elasticity — Bifurcation theory

v1.3 research notes

Develop local and global bifurcation theories for nonlinear elastostatics with mixed displacement-traction boundary conditions....

L3
Partial Differential Equations
AMR-019-0011
Partially Solved

Some Open Problems in Elasticity — Variational fracture models

v1.3 research notes

Clarify the status of models based on the fracture energy functional (2.31) in the source relative to classical fracture and nonlinear elastostatics....

L3
Partial Differential Equations
AMR-019-0012
Partially Solved

Some Open Problems in Elasticity — Global dynamics

v1.3 research notes

Prove global existence and uniqueness for suitable initial-boundary-value problems in dynamic nonlinear elasticity....

L4
Partial Differential Equations
AMR-019-0013
Open

Some Open Problems in Elasticity — Qualitative dynamics

v1.3 research notes

Develop a qualitative dynamics for dynamic theories of elasticity....

L3
Partial Differential Equations
AMR-019-0014
Partially Solved

Some Open Problems in Elasticity — Dynamic stability

v1.3 research notes

Develop criteria for dynamic stability and instability of equilibria in nonlinear elasticity....

L3
Partial Differential Equations
AMR-019-0015
Open

Some Open Problems in Elasticity — Atomistic foundations

v1.3 research notes

Establish the status of elasticity theory with respect to atomistic models....

L3
Partial Differential Equations
AMR-019-0016
Partially Solved

Some Open Problems in Elasticity — Quasiconvexification of energy wells

v1.3 research notes

For the set of energy-minimizing gradients $K(\theta)$ defined in the source, determine its quasiconvex hull $K(\theta)^{qc}$ for $\theta\le\theta_c$....

L3
Partial Differential Equations
AMR-019-0017
Open

Some Open Problems in Elasticity — Elastic-crystal free energies

v1.3 research notes

For free-energy functions $\psi(A,\theta)$ of elastic crystals, determine boundary conditions under which the minimum is attained and conditions under...

L3
Partial Differential Equations
AMR-019-0018
Partially Solved

Some Open Problems in Elasticity — Dimension reduction

v1.3 research notes

Give a rigorous derivation of models of rods, plates, and shells from three-dimensional elasticity as thickness tends to zero....

L3
Partial Differential Equations
AMR-023-0014
Partially Solved

Vlasov–Maxwell regularity

v1.3 research notes

Establish global regularity, or exhibit breakdown, for solutions of the Vlasov–Maxwell equations from appropriate smooth initial data....

L4
Partial Differential Equations
AMR-024-0003
Open

Finite-dimensional dynamics for two-dimensional Navier–Stokes

v1.3 research notes

Is the global attractor of the periodically forced two-dimensional Navier–Stokes equations conjugate to a smooth finite-dimensional dynamical system? ...

L4
Partial Differential Equations
AMR-024-0004
Partially Solved

Dissipation bounds for flow past an obstacle

v1.3 research notes

For viscous incompressible flow in $\mathbb{R}^3\setminus B$ past a fixed obstacle $B$, with velocity approaching a nonzero constant vector at infinit...

L3
Partial Differential Equations
AMR-026-0001
Partially Solved

Five Open Problems — Global Cauchy theory for one-dimensional Euler–Fourier flow

v1.3 research notes

Develop a global-in-time theory of the Cauchy problem for the one-dimensional Euler–Fourier system for initial data constrained only by finite energy ...

L4
Partial Differential Equations
AMR-026-0002
Partially Solved

Five Open Problems — Compensated compactness for symmetric matrices

v1.3 research notes

Develop a compensated-compactness calculus for symmetric matrices when compensated compactness yields only inequalities. As a first application, prove...

L4
Partial Differential Equations
AMR-026-0003
Partially Solved

Five Open Problems — Compressible Navier–Stokes near vacuum

v1.3 research notes

For compressible Navier–Stokes equations with constant viscosities near vacuum, does the unphysical one-dimensional consequence identified by Hoff and...

L4
Partial Differential Equations
AMR-026-0004
Partially Solved

Five Open Problems — Eternal finite-energy compressible Euler flow

v1.3 research notes

Does the compressible Euler system in odd spatial dimension admit a nontrivial smooth eternal solution having finite nonzero mass and energy?...

L4
Partial Differential Equations
AMR-026-0005
Partially Solved

Five Open Problems — Regular reflection without irrotationality

v1.3 research notes

Prove existence of a regular reflection for compressible flow against a wedge without assuming that the flow is irrotational....

L4
Partial Differential Equations
AMR-064-0007
Partially Solved

Localized Degenerate Control of Navier-Stokes

v1.3 research notes

For incompressible Navier-Stokes on $\mathbb{T}^d$, $d=2,3$, is the system approximately controllable and/or controllable in finite-dimensional projec...

L4
Partial Differential Equations