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20182026
most citedQuasiconvexity, null Lagrangians, and Hardy space integrability under constant rank constraints

22 citations · 77 across the 17 of their papers we have counts for

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14 papers · 1 filter

math.AP2026

On the effective sharp stability of the Faber-Krahn inequality

André Guerra, João Miguel Machado, João P. G. Ramos

We prove the sharp quantitative Faber--Krahn inequality with a computable dimensional constant, resolving a problem posed by Brasco and De Philippis~\cite[Open Problem~2]{brasco201…

math.AP2026

Morrey's problem in and

Andrea Agazzi, Giuseppe Bruno, André Guerra +1

We find an explicit rank-one convex non-quasiconvex integrand in : to falsify the quasiconvexity inequality, we exhibit a map …

math.AP2026

On the sharp Hölder exponent in the De Giorgi--Nash--Moser theory

André Guerra

We consider solutions of uniformly elliptic equations with measurable coefficients. We assume that the lowest eigenvalue of the coefficient matrix is at least and the larg…

math.AP2023★ 1 cited

Sharp quantitative stability of the Möbius group among sphere-valued maps in arbitrary dimension

André Guerra, Xavier Lamy, Konstantinos Zemas

In this work we prove a sharp quantitative form of Liouville's theorem, which asserts that, for all , the weakly conformal maps of with degree ar…

math.AP2021

Automatic quasiconvexity of homogeneous isotropic rank-one convex integrands

André Guerra, Jan Kristensen

We consider the class of non-negative rank-one convex isotropic integrands on which are also positively -homogeneous. If we prove, condit…

math.AP2021

Compensation phenomena for concentration effects via nonlinear elliptic estimates

André Guerra, Bogdan Raiţă, Matthew Schrecker

We study compensation phenomena for fields satisfying both a pointwise and a linear differential constraint. This effect takes the form of nonlinear elliptic estimates, where const…

math.AP2021★ 3 cited

Oscillations in wave map systems and homogenization of the Einstein equations in symmetry

André Guerra, Rita Teixeira da Costa

In 1989, Burnett conjectured that, under appropriate assumptions, the limit of highly oscillatory solutions to the Einstein vacuum equations is a solution of the Einstein--massless…

math.AP2020★ 7 cited

Energy minimisers with prescribed Jacobian

André Guerra, Lukas Koch, Sauli Lindberg

We study the symmetry and uniqueness of maps which minimise the -Dirichlet energy, under the constraint that their Jacobian is a given radially symmetric function . We find…

math.AP2020

Nonlinear open mapping principles, with applications to the Jacobian equation and other scale-invariant PDEs

André Guerra, Lukas Koch, Sauli Lindberg

For a nonlinear operator satisfying certain structural assumptions, our main theorem states that the following claims are equivalent: i) is surjective, ii) is open at z…

math.AP2020★ 7 cited

The Dirichlet problem for the Jacobian equation in critical and supercritical Sobolev spaces

André Guerra, Lukas Koch, Sauli Lindberg

We study existence and regularity of solutions to the Dirichlet problem for the prescribed Jacobian equation, , where is integrable and bounded away from zero. In…

math.AP2020★ 12 cited

Compensated compactness: continuity in optimal weak topologies

André Guerra, Bogdan Raiţă, Matthew R. I. Schrecker

For -homogeneous linear differential operators of constant rank, we study the implication in and $\mathcal{A} v_j\rightarrow \mathcal{A}…

math.AP2020★ 7 cited

Remarks on Ornstein's non-inequality in

Daniel Faraco, André Guerra

We give a very concise proof of Ornstein's non-inequality for first- and second-order operators in two dimensions. The proof just needs a two-dimensional laminate supported o…

math.AP2019★ 22 cited

Quasiconvexity, null Lagrangians, and Hardy space integrability under constant rank constraints

André Guerra, Bogdan Raiţă

We present a systematic treatment of the theory of Compensated Compactness under Murat's constant rank assumption. We give a short proof of a sharp weak lower semicontinuity result…

math.AP2018★ 4 cited

Extremal rank-one convex integrands and a conjecture of Šverák

André Guerra

We show that in order to decide whether a given probability measure is laminate it is enough to verify Jensen's inequality in the class of extremal non-negative rank-one convex int…