2 research outputs found

    CFT dual of the AdS Dirichlet problem: Fluid/Gravity on cut-off surfaces

    Full text link
    We study the gravitational Dirichlet problem in AdS spacetimes with a view to understanding the boundary CFT interpretation. We define the problem as bulk Einstein's equations with Dirichlet boundary conditions on fixed timelike cut-off hypersurface. Using the fluid/gravity correspondence, we argue that one can determine non-linear solutions to this problem in the long wavelength regime. On the boundary we find a conformal fluid with Dirichlet constitutive relations, viz., the fluid propagates on a `dynamical' background metric which depends on the local fluid velocities and temperature. This boundary fluid can be re-expressed as an emergent hypersurface fluid which is non-conformal but has the same value of the shear viscosity as the boundary fluid. The hypersurface dynamics arises as a collective effect, wherein effects of the background are transmuted into the fluid degrees of freedom. Furthermore, we demonstrate that this collective fluid is forced to be non-relativistic below a critical cut-off radius in AdS to avoid acausal sound propagation with respect to the hypersurface metric. We further go on to show how one can use this set-up to embed the recent constructions of flat spacetime duals to non-relativistic fluid dynamics into the AdS/CFT correspondence, arguing that a version of the membrane paradigm arises naturally when the boundary fluid lives on a background Galilean manifold.Comment: 71 pages, 2 figures. v2: Errors in bulk metrics dual to non-relativistic fluids (both on cut-off surface and on the boundary) have been corrected. New appendix with general results added. Fixed typos. 82 pages, 2 figure

    ACE inhibitors and myocardial remodeling in patients with arterial hypertension and atrial fibrillation

    No full text
    The study is focused on assessing dynamics of left atrium volume and volume index after treatment of paroxysmal or persistent atrial fibrillation (AF), during ACE therapy with lipophilic (n=34) or hydrophilic (n=38) «standard» antihypertensive medications. After sinus rhythm restoration, mechanical dysfunction of left atrium was observed in 95, 8 % of the participants. Standard antihypertensive therapy, including lipophilic or hydrophilic ACE inhibitors, resulted in improved left atrium mechanical function and heart remodeling in 82, 1 %. Hydrophilic ACE inhibitor (Dapril) was no less effective than lipophilic medication (enalapril), being even more effective in terms of duration and dynamics of left atrium mechanical function recovery. Dapril demonstrated high effectiveness, no less than for enalapril, together with minimal adverse event rate (0 % vs 14 %>, respectively). This could improve patients' compliance to persistent medication therapy of the principal pathology
    corecore