References and Remarks on Rotating Fluids

Author(s):  
Jean-Yves Chemin ◽  
Benoit Desjardins ◽  
Isabelle Gallagher ◽  
Emmanuel Grenier

The problem investigated in this part can be seen as a particular case of the study of the asymptotic behavior (when ε tends to 0) of solutions of systems of the type where Δε is a non-negative operator of order 2 possibly depending on ε, and A is a skew-symmetric operator. This framework contains of course a lot of problems including hyperbolic cases when Δε = 0. Let us notice that, formally, any element of the weak closure of the family (uε)ε>0 belongs to the kernel of A. We can distinguish from the beginning two types of problems depending on the nature of the initial data. The first case, known as the well-prepared case, is the case when the initial data belong to the kernel of A. The second case, known as the ill-prepared case, is the general case. In the well-prepared case, let us mention the pioneer paper by S. Klainerman and A. Majda about the incompressible limit for inviscid fluids. A lot of work has been done in this case. In the more specific case of rotating fluids, let us mention the work by T. Beale and A. Bourgeois and T. Colin and P. Fabrie. In the case of ill-prepared data, the nature of the domain plays a crucial role. The first result in this case was established in 1994 in the pioneering work by S. Schochet for periodic boundary conditions. In the context of general hyperbolic problems, he introduced the key concept of limiting system (see the definition on page 125). In the more specific case of viscous rotating fluids, E. Grenier proved in 1997 in Theorem 6.3, page 125, of this book. At this point, it is impossible not to mention the role of the inspiration played by the papers by J.-L. Joly, G. Métivier and J. Rauch (see for instance and). In spite of the fact that the corresponding theorems have been proved afterwards, the case of the whole space, the purpose of Chapter 5 of this book, appears to be simpler because of the dispersion phenomena.

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Mengmeng Liu ◽  
Xueyun Lin

AbstractIn this paper, we show the global existence of classical solutions to the incompressible elastodynamics equations with a damping mechanism on the stress tensor in dimension three for sufficiently small initial data on periodic boxes, that is, with periodic boundary conditions. The approach is based on a time-weighted energy estimate, under the assumptions that the initial deformation tensor is a small perturbation around an equilibrium state and the initial data have some symmetry.


2004 ◽  
Vol 2004 (57) ◽  
pp. 3045-3056 ◽  
Author(s):  
Constantin Udrişte ◽  
Ana-Maria Teleman

We extend some results and concepts of single-time covariant Hamiltonian field theory to the new context of multitime covariant Hamiltonian theory. In this sense, we point out the role of the polysymplectic structureδ⊗J, we prove that the dual action is indefinite, we find the eigenvalues and the eigenfunctions of the operator(δ⊗J)(∂/∂t)with periodic boundary conditions, and we obtain interesting inequalities relating functionals created by the new context. As an important example for physics and differential geometry, we study the multitime Yang-Mills-Witten Hamiltonian, extending the Legendre transformation in a suitable way. Our original results are accompanied by well-known relations between Lagrangian and Hamiltonian, and by geometrical explanations regarding the Yang-Mills-Witten Lagrangian.


2019 ◽  
Author(s):  
Yunqi Shao ◽  
Keisuke Shigenobu ◽  
Masayoshi Watanabe ◽  
Chao Zhang

<div><div><div><p>Deviations from the Nernst-Einstein rela- tion are commonly attributed to ion-ion (cross)correlation and ion-pairing. Despite the fact that these deviations can be quantified by either experimental measurements or molecular dynamics simulations, there is no rule of thumb to tell the extent of deviations. Here, we show that deviations from the Nernst-Einstein relation scale linearly with the inverse viscosity by exploring the finite-size effect in periodic boundary conditions. This conclusion is in accord with published experimental results of ionic liquids.</p></div></div></div>


2009 ◽  
Vol 24 (19) ◽  
pp. 1495-1506 ◽  
Author(s):  
R. OBOUSY ◽  
G. CLEAVER

One of the challenges in connecting higher dimensional theories to cosmology is stabilization of the moduli fields. We investigate the role of a Lorentz violating vector field in the context of stabilization. Specifically, we compute the one-loop Casimir energy in Randall–Sundrum five-dimensional (non-supersymmetric) S1/ Z2 orbifolds resulting from the interaction of a real scalar field with periodic boundary conditions with a Lorentz violating vector field. We find that the result is an enhanced attractive Casimir force. Hence, for stability, positive contributions to the Casimir force from branes and additional fields would be required to counter the destabilizing, attractive effect of Lorentz violating fields.


2020 ◽  
Author(s):  
Yunqi Shao ◽  
Keisuke Shigenobu ◽  
Masayoshi Watanabe ◽  
Chao Zhang

<p> </p><div> <div> <div> <p>Deviations from the Nernst-Einstein relation are commonly attributed to ion-ion correlation and ion-pairing. Despite the fact that these de- viations can be quantified by either experimental measurements or molecular dynamics simulations, there is no rule of thumb to tell the extent of deviations. Here, we show that deviations from the Nernst-Einstein relation is proportional to the inverse viscosity by exploring the finite-size effect on the transport properties in periodic boundary conditions. This conclusion is in accord with established experimental results of ionic liquids. </p> </div> </div> </div><br><p></p>


2020 ◽  
Author(s):  
Yunqi Shao ◽  
Keisuke Shigenobu ◽  
Masayoshi Watanabe ◽  
Chao Zhang

<p> </p><div> <div> <div> <p>Deviations from the Nernst-Einstein relation are commonly attributed to ion-ion correlation and ion-pairing. Despite the fact that these de- viations can be quantified by either experimental measurements or molecular dynamics simulations, there is no rule of thumb to tell the extent of deviations. Here, we show that deviations from the Nernst-Einstein relation is proportional to the inverse viscosity by exploring the finite-size effect on the transport properties in periodic boundary conditions. This conclusion is in accord with established experimental results of ionic liquids. </p> </div> </div> </div><br><p></p>


1994 ◽  
Vol 09 (15) ◽  
pp. 2563-2582 ◽  
Author(s):  
SERGEI B. ISAKOV

The equivalence of a quantum system of particles interacting with a two-body inverse square potential to a system of noninteracting particles obeying 1D fractional statistics (1D anyons), stated by Polychronakos for particles on a line, is studied for the cases where the interacting system is placed (i) into a harmonic potential on a line, and (ii) on a ring, with imposing periodic boundary conditions. In the first case, reducibility of the interacting system to the Calogero system is used to explore the statistical distribution for free 1D anyons. On a ring, the thermodynamic limit is discussed in terms of the thermodynamic (asymptotic) Bethe ansatz. Yang and Yang’s integral equation is treated in this case as describing the statistical mechanics of free 1D anyons. It gives a functional equation for the statistical distribution of 1D anyons consistent with the harmonic potential approach. We show that on a ring of a finite circumference, a system of two free 1D anyons is equivalent to a system of two particles interacting with an inverse sine square potential (the Sutherland system). We also discuss the relation to the statistical mechanics of free anyons in 2+1 dimensions.


2020 ◽  
Vol 2 (9) ◽  
Author(s):  
Ahmed Samir Abdelhafiz ◽  
Mona Wassef ◽  
Mohamed Alorabi

Background. Salmonella species are motile, Gram-negative facultative anaerobic bacilli, which belong to the family Enterobacteriaceae . The most common clinical presentations of Salmonella infection are gastroenteritis and enteric fever. Detection of Salmonella organisms in empyema is very rare. Case presentation. We report the case of a 66-year-old female patient with bronchogenic carcinoma who developed empyema, and Salmonella was identified from the culture of pleural fluid. After antimicrobial therapy and other therapeutic measures, including the insertion of an intercostal tube, oxygen supplementation, frequent suction of respiratory secretions, and chest physiotherapy, the patient's condition improved. To the best of our knowledge, this is the first case to be reported in Egypt. Conclusions. Our case sheds light on the role of Salmonella in immunocompromised patients in general and cancer patients in specific. We recommend further study of this role, since it may lead to a better understanding of the pathogenicity of this organism in these patients.


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