Complete Classification of Four-Dimensional Black Hole and Membrane Solutions in IR-modified Ho\v{r}ava Gravity

Ho\v{r}ava gravity has been proposed as a renormalizable, higher-derivative gravity without ghost problems, by considering different scaling dimensions for space and time. In the non-relativistic higher-derivative generalization of Einstein gravity, the meaning and physical properties of black hole and membrane space-times are quite different from the conventional ones. Here, we study the singularity and horizon structures of such geometries in IR-modified Ho\v{r}ava gravity, where the so-called "detailed balance" condition is softly broken in IR. We classify all the viable static solutions without naked singularities and study its close connection to non-singular cosmology solutions. We find that, in addition to the usual point-like singularity at $r=0$, there exists a "surface-like" curvature singularity at finite $r=r_S$ which is the cutting edge of the real-valued space-time. The degree of divergence of such singularities is milder than those of general relativity, and the Hawking temperature of the horizons diverges when they coincide with the singularities. As a byproduct we find that, in addition to the usual "asymptotic limit," a consistent flow of coupling constants, that we called "GR flow limit," is needed in order to recover general relativity in the IR.Comment: Accepted in JHEP, Typos correcte

Heat-shock response in a yeast tps1 mutant deficient in trehalose synthesis

AbstractExponential cells of the Saccharomyces cerevisiae tps1 mutant underwent a rapid loss of viability upon a non-lethal heat exposure (from 28 to 42°C). However, a further more severe heat stress (52.5°C 5 min) induced an increase in the fraction of viable cells. This mutant can not synthesize trehalose either at 28° C or at 42°C due to the lack of a functional trehalose-6P synthase complex. In control experiments carried out with the wild-type W303-1 B, heat-stressed exponential phase cultures grown on YPgal at 28°C acquired thermotolerance to a higher extent than identical cultures grown on YPD, although in both cultures the level of stored trehalose was negligible. These data suggest that the bulk of trehalose accumulated in yeast upon mild heat treaments is not sufficient to account for the acquisition of thermotolerance

The colours in the heraldry of the libros de caballerías

[Resumen] Se analiza en detalle el simbolismo expresado mediante los colores del campo del escudo y la cota de armas de los personajes de 36 libros de caballerías impresos en el siglo XVI, y se comparan las preferencias cromáticas literarias con las observadas en la heráldica castellana real compuesta durante ese mismo periodo y también con las desarrolladas previamente en las novelas del ciclo artúrico. Las correspondencias entre colores y sentimientos propuestas por los tratadistas del siglo XV tuvieron una influencia determinante en el entintado de los escudos novelescos, pero afectaron muy poco a la coloración de los auténticos, exceptuando la promoción de un decidido gusto por el verde que, sin embargo, careció de intenciones simbólicas. El uso de alegorías cromáticas fue mucho más amplio en los libros de caballerías que en la literatura artúrica y la elección de colores en cada caso respondió a propósitos generalmente diferentes[Abstract] The symbolism expressed by the colours of the field of the heraldic shield and the armorial coat of the characters in 36 Spanish romances of chivalry (libros de caballerías) printed in the XVIth century is analysed in detail, and the literary chromatic preferences are compared to those observed in real Castilian heraldry composed during the same period and also to those pertaining to previous Arthurian narrative. The correspondence between colours and emotions proposed by the authors of XVth century treatises exerted a determinant influence on the colouring of fiction arms, but scarcely affected that of the authentic ones, excepting the promotion of a definite taste for the green, which was nevertheless devoid of symbolic purposes. The use of chromatic allegories was much wider in the romances of chivalry than in the Arthurian literature, and the choice of colours was generally intended to represent different intentions in each instanc

The heraldic imagination in XVIth century Spain. The arms of the caciques and the american charges

Se analizan 23 armerías concedidas por la corona a los aliados indígenas de los conquistadores y los descendientes de los destronados soberanos aztecas e incas, caracterizadas por: 1) novedosos muebles de inspiración autóctona (accidentes geográficos, flora y fauna, construcciones y productos de la industria local); 2) marcas totémicas y atributos de caciques y monarcas indígenas transformados en muebles heráldicos que siguieron cumpliendo su primitiva función identificadora en el nuevo contexto plástico; y 3) una clara preferencia por el diseño naturalista iniciada a mediados del siglo XVI.23 coats of arms granted by the Spanish crown to the indigenous auxiliaries of the conquistadores and the descendants of the deposed aztec and inca rulers are analyzed, characterized by: 1) novel charges of autochthonous inspiration (geographical accidents, flora and fauna, constructions and products of the local industry); 2) totemic marks and badges of the native sovereigns and caciques converted into heraldic charges which adequately accomplished their previous identifying function in the new plastic context; 3) a definite preference for naturalistic representations starting from the middle years of the XVIth century

Exploring a Non-Minimal Sterile Neutrino Model Involving Decay at IceCube and Beyond

We study the phenomenology of neutrino decay together with neutrino oscillations in the context of eV-scale sterile neutrinos. We review the formalism of visible neutrino decay in which one of the decay products is a neutrino that potentially can be observed. We apply the formalism developed for decay to the recent sterile neutrino search performed by IceCube with TeV neutrinos. We show that for $\nu_4$ lifetime $\tau_4/m_4 \lesssim 10^{-16} {\rm eV^{-1}s}$, the interpretation of the high-energy IceCube analysis can be significantly changed.Comment: 12 pages, 7 figures. Find code at: https://github.com/arguelles/nuSQUIDSDeca