Annals of PdePub Date : 2022-01-11DOI: 10.1007/s40818-021-00115-0
Mitia Duerinckx, Antoine Gloria
{"title":"Sedimentation of random suspensions and the effect of hyperuniformity","authors":"Mitia Duerinckx, Antoine Gloria","doi":"10.1007/s40818-021-00115-0","DOIUrl":"10.1007/s40818-021-00115-0","url":null,"abstract":"<div><p>This work is concerned with the mathematical analysis of the bulk rheology of random suspensions of rigid particles settling under gravity in viscous fluids. Each particle generates a fluid flow that in turn acts on other particles and hinders their settling. In an equilibrium perspective, for a given ensemble of particle positions, we analyze both the associated mean settling speed and the velocity fluctuations of individual particles. In the 1970s, Batchelor gave a proper definition of the mean settling speed, a 60-year-old open problem in physics, based on the appropriate renormalization of long-range particle contributions. In the 1980s, a celebrated formal calculation by Caflisch and Luke suggested that velocity fluctuations in dimension <span>(d=3)</span> should diverge with the size of the sedimentation tank, contradicting both intuition and experimental observations. The role of long-range self-organization of suspended particles in form of hyperuniformity was later put forward to explain additional screening of this divergence in steady-state observations. In the present contribution, we develop the first rigorous theory that allows to justify all these formal calculations of the physics literature.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"8 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2022-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50470902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-12-22DOI: 10.1007/s40818-021-00116-z
Daniel Lear, David N. Reynolds, Roman Shvydkoy
{"title":"Global Solutions to Multi-dimensional Topological Euler Alignment Systems","authors":"Daniel Lear, David N. Reynolds, Roman Shvydkoy","doi":"10.1007/s40818-021-00116-z","DOIUrl":"10.1007/s40818-021-00116-z","url":null,"abstract":"<div><p>We present a systematic approach to regularity theory of the multi-dimensional Euler alignment systems with topological diffusion introduced in [35]. While these systems exhibit flocking behavior emerging from purely local communication, bearing direct relevance to empirical field studies, global and even local well-posedness has proved to be a major challenge in multi-dimensional settings due to the presence of topological effects. In this paper we reveal two important classes of global smooth solutions—parallel shear flocks with incompressible velocity and stationary density profile, and nearly aligned flocks with close to constant velocity field but arbitrary density distribution. Existence of such classes is established via an efficient continuation criterion requiring control only on the Lipschitz norm of state quantities, which makes it accessible to the applications of fractional parabolic theory. The criterion presents a major improvement over the existing result of [28], and is proved with the use of quartic paraproduct estimates.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"8 1","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50504574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-10-19DOI: 10.1007/s40818-021-00112-3
Paolo Antonelli, Michele Dolce, Pierangelo Marcati
{"title":"Linear stability analysis of the homogeneous Couette flow in a 2D isentropic compressible fluid","authors":"Paolo Antonelli, Michele Dolce, Pierangelo Marcati","doi":"10.1007/s40818-021-00112-3","DOIUrl":"10.1007/s40818-021-00112-3","url":null,"abstract":"<div><p>In this paper, we study the linear stability properties of perturbations around the homogeneous Couette flow for a 2D isentropic compressible fluid in the domain <span>(mathbb {T}times mathbb {R})</span>. In the inviscid case there is a generic Lyapunov type instability for the density and the irrotational component of the velocity field. More precisely, we prove that their <span>(L^2)</span> norm grows as <span>(t^{1/2})</span> and this confirms previous observations in the physics literature. On the contrary, the solenoidal component of the velocity field experiences inviscid damping, namely it decays to zero even in the absence of viscosity. For a viscous compressible fluid, we show that the perturbations may have a transient growth of order <span>(nu ^{-1/6})</span> (with <span>(nu ^{-1})</span> being proportional to the Reynolds number) on a time-scale <span>(nu ^{-1/3})</span>, after which it decays exponentially fast. This phenomenon is also called enhanced dissipation and our result appears to be the first to detect this mechanism for a compressible flow, where an exponential decay for the density is not a priori trivial given the absence of dissipation in the continuity equation.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40818-021-00112-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50497360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-09-23DOI: 10.1007/s40818-021-00113-2
Feimin Huang, Jie Kuang, Dehua Wang, Wei Xiang
{"title":"Stability of Transonic Contact Discontinuity for Two-Dimensional Steady Compressible Euler Flows in a Finitely Long Nozzle","authors":"Feimin Huang, Jie Kuang, Dehua Wang, Wei Xiang","doi":"10.1007/s40818-021-00113-2","DOIUrl":"10.1007/s40818-021-00113-2","url":null,"abstract":"<div><p>We consider the stability of transonic contact discontinuity for the two-dimensional steady compressible Euler flows in a finitely long nozzle. This is the first work on the mixed-type problem of transonic flows across a contact discontinuity as a free boundary in nozzles. We start with the Euler-Lagrangian transformation to straighten the contact discontinuity in the new coordinates. However, the upper nozzle wall in the subsonic region depending on the mass flux becomes a free boundary after the transformation. Then we develop new ideas and techniques to solve the free-boundary problem in three steps: (1) we fix the free boundary and generate a new iteration scheme to solve the corresponding fixed boundary value problem of the hyperbolic-elliptic mixed type by building some powerful estimates for both the first-order hyperbolic equation and a second-order nonlinear elliptic equation in a Lipschitz domain; (2) we update the new free boundary by constructing a mapping that has a fixed point; (3) we establish via the inverse Lagrangian coordinate transformation that the original free interface problem admits a unique piecewise smooth transonic solution near the background state, which consists of a smooth subsonic flow and a smooth supersonic flow with a contact discontinuity.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40818-021-00113-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50509261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-27DOI: 10.1007/s40818-021-00108-z
Juhi Jang, Chanwoo Kim
{"title":"Incompressible Euler Limit from Boltzmann Equation with Diffuse Boundary Condition for Analytic Data","authors":"Juhi Jang, Chanwoo Kim","doi":"10.1007/s40818-021-00108-z","DOIUrl":"10.1007/s40818-021-00108-z","url":null,"abstract":"<div><p>A rigorous derivation of the incompressible Euler equations with the no-penetration boundary condition from the Boltzmann equation with the diffuse reflection boundary condition has been a challenging open problem. We settle this open question in the affirmative when the initial data of fluid are well-prepared in a real analytic space, in 3D half space. As a key of this advance, we capture the Navier-Stokes equations of </p><div><div><span>$$begin{aligned} textit{viscosity} sim frac{textit{Knudsen number}}{textit{Mach number}} end{aligned}$$</span></div></div><p>satisfying the no-slip boundary condition, as an <i>intermediary</i> approximation of the Euler equations through a new Hilbert-type expansion of the Boltzmann equation with the diffuse reflection boundary condition. Aiming to justify the approximation we establish a novel quantitative <span>(L^p)</span>-<span>(L^infty )</span> estimate of the Boltzmann perturbation around a local Maxwellian of such viscous approximation, along with the commutator estimates and the integrability gain of the hydrodynamic part in various spaces; we also establish direct estimates of the Navier-Stokes equations in higher regularity with the aid of the initial-boundary and boundary layer weights using a recent Green’s function approach. The incompressible Euler limit follows as a byproduct of our framework.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00108-z","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50517041","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-25DOI: 10.1007/s40818-021-00107-0
Zonglin Han, Andrej Zlatoš
{"title":"Euler Equations on General Planar Domains","authors":"Zonglin Han, Andrej Zlatoš","doi":"10.1007/s40818-021-00107-0","DOIUrl":"10.1007/s40818-021-00107-0","url":null,"abstract":"<div><p>We obtain a general sufficient condition on the geometry of possibly singular planar domains that guarantees global uniqueness for any weak solution to the Euler equations on them whose vorticity is bounded and initially constant near the boundary. While similar existing results require domains that are <span>(C^{1,1})</span> except at finitely many convex corners, our condition involves much less domain smoothness, being only slightly more restrictive than the exclusion of corners with angles greater than <span>(pi )</span>. In particular, it is satisfied by all convex domains. The main ingredient in our approach is showing that constancy of the vorticity near the boundary is preserved for all time because Euler particle trajectories on these domains, even for general bounded solutions, cannot reach the boundary in finite time. We then use this to show that no vorticity can be created by the boundary of such possibly singular domains for general bounded solutions. We also show that our condition is essentially sharp in this sense by constructing domains that come arbitrarily close to satisfying it, and on which particle trajectories can reach the boundary in finite time. In addition, when the condition is satisfied, we find sharp bounds on the asymptotic rate of the fastest possible approach of particle trajectories to the boundary.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00107-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50511555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-25DOI: 10.1007/s40818-021-00111-4
Bjoern Bringmann, Rowan Killip, Monica Visan
{"title":"Global Well-Posedness for the Fifth-Order KdV Equation in (H^{-1}(pmb {mathbb {R}}))","authors":"Bjoern Bringmann, Rowan Killip, Monica Visan","doi":"10.1007/s40818-021-00111-4","DOIUrl":"10.1007/s40818-021-00111-4","url":null,"abstract":"<div><p>We prove global well-posedness of the fifth-order Korteweg-de Vries equation on the real line for initial data in <span>(H^{-1}(mathbb {R}))</span>. Global well-posedness in <span>(L^2({mathbb {R}}))</span> was shown previously in [8] using the method of commuting flows. Since this method is insensitive to the ambient geometry, it cannot go beyond the sharp <span>( L^2)</span> threshold for the torus demonstrated in [3]. To prove our result, we introduce a new strategy that integrates dispersive effects into the method of commuting flows.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00111-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50511554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-22DOI: 10.1007/s40818-021-00109-y
Marco Cirant, Alessandro Goffi
{"title":"Maximal (L^q)-Regularity for Parabolic Hamilton–Jacobi Equations and Applications to Mean Field Games","authors":"Marco Cirant, Alessandro Goffi","doi":"10.1007/s40818-021-00109-y","DOIUrl":"10.1007/s40818-021-00109-y","url":null,"abstract":"<div><p>In this paper we investigate maximal <span>(L^q)</span>-regularity for time-dependent viscous Hamilton–Jacobi equations with unbounded right-hand side and superlinear growth in the gradient. Our approach is based on the interplay between new integral and Hölder estimates, interpolation inequalities, and parabolic regularity for linear equations. These estimates are obtained via a duality method à la Evans. This sheds new light on the parabolic counterpart of a conjecture by P.-L. Lions on maximal regularity for Hamilton–Jacobi equations, recently addressed in the stationary framework by the authors. Finally, applications to the existence problem of classical solutions to Mean Field Games systems with unbounded local couplings are provided.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00109-y","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50504595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-20DOI: 10.1007/s40818-021-00110-5
Daniel Han-Kwan, Toan T. Nguyen, Frédéric Rousset
{"title":"Asymptotic Stability of Equilibria for Screened Vlasov–Poisson Systems via Pointwise Dispersive Estimates","authors":"Daniel Han-Kwan, Toan T. Nguyen, Frédéric Rousset","doi":"10.1007/s40818-021-00110-5","DOIUrl":"10.1007/s40818-021-00110-5","url":null,"abstract":"<div><p>We revisit the proof of Landau damping near stable homogenous equilibria of Vlasov–Poisson systems with screened interactions in the whole space <span>(mathbb {R}^d)</span> (for <span>(dge 3)</span>) that was first established by Bedrossian, Masmoudi and Mouhot in [5]. Our proof follows a Lagrangian approach and relies on precise pointwise in time dispersive estimates in the physical space for the linearized problem that should be of independent interest. This allows to cut down the smoothness of the initial data required in [5] (roughly, we only need Lipschitz regularity). Moreover, the time decay estimates we prove are essentially sharp, being the same as those for free transport, up to a logarithmic correction.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00110-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50498656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annals of PdePub Date : 2021-08-18DOI: 10.1007/s40818-021-00106-1
Felix Otto, Maxime Prod’homme, Tobias Ried
{"title":"Variational Approach to Regularity of Optimal Transport Maps: General Cost Functions","authors":"Felix Otto, Maxime Prod’homme, Tobias Ried","doi":"10.1007/s40818-021-00106-1","DOIUrl":"10.1007/s40818-021-00106-1","url":null,"abstract":"<div><p>We extend the variational approach to regularity for optimal transport maps initiated by Goldman and the first author to the case of general cost functions. Our main result is an <span>(epsilon )</span>-regularity result for optimal transport maps between Hölder continuous densities slightly more quantitative than the result by De Philippis–Figalli. One of the new contributions is the use of almost-minimality: if the cost is quantitatively close to the Euclidean cost function, a minimizer for the optimal transport problem with general cost is an almost-minimizer for the one with quadratic cost. This further highlights the connection between our variational approach and De Giorgi’s strategy for <span>(epsilon )</span>-regularity of minimal surfaces.</p></div>","PeriodicalId":36382,"journal":{"name":"Annals of Pde","volume":"7 2","pages":""},"PeriodicalIF":2.8,"publicationDate":"2021-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s40818-021-00106-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50492387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}