A
bstract
A transformation is introduced in momentum representation to keep a covariant description at every stage of a loop computation in gravity. The procedure treats on equal footing local ...internal and space-time symmetries althought the complete transformation is known for the former
1
whereas in gravity we solve for the first few orders in an expansion. As an explicit application the one loop UV divergences of Hilbert-Einstein gravity with a cosmological constant and spin 0, 1/2 and 1 matter are computed with functional methods and in a field-covariant formalism.
A
bstract
There exist non-trivial stationary points of the Euclidean action for an axion particle minimally coupled to Einstein gravity, dubbed wormholes. They explicitly break the continuos global ...shift symmetry of the axion in a non-perturbative way, and generate an effective potential that may compete with QCD depending on the value of the axion decay constant. In this paper, we explore both theoretical and phenomenological aspects of this issue. On the theory side, we address the problem of stability of the wormhole solutions, and we show that the spectrum of the quadratic action features only positive eigenvalues. On the phenomenological side, we discuss, beside the obvious application to the QCD axion, relevant consequences for models with ultralight dark matter and black hole superradiance. We conclude discussing wormhole solutions for a generic coset and the potential they generate.
Diagnosis and Management of Statin Intolerance Alonso, Rodrigo; Cuevas, Ada; Cafferata, Alberto
Journal of Atherosclerosis and Thrombosis,
03/2019, Letnik:
26, Številka:
3
Journal Article
Odprti dostop
Statins are the main treatment for hypercholesterolemia and the cornerstone of atherosclerotic cardiovascular disease prevention. Many patients taking statins report muscle-related symptoms, one of ...the most important causes of statin treatment discontinuation, which is associated with an increased risk of cardiovascular events. Therefore, it is important to identify patients who are truly statin intolerant to avoid unnecessary discontinuation of this beneficial treatment. Some studies indicate that not all muscle complaints are caused by statins, and most patients can tolerate a statin upon re-challenge, down-titration of dose, or switching to another statin. In this paper, we review the definitions of statin intolerance and approaches to reducing cardiovascular risk among individuals reporting statin-associated muscle symptoms.
Functional methods and a derivative expansion are employed for laying out a procedure to compute the effective action to any loop order, for scalar fields parametrising an arbitrary Riemannian ...manifold, while maintaining explicit field-space covariance. These results are of use in the characterization of effective field theories for electroweak symmetry breaking and extend a geometric perspective in field space beyond one loop.
We consider a flavoured B−L gauge symmetry under which only the third generation fermions are charged. Such a symmetry can survive at low energies (∼TeV) while still allowing for two superheavy ...right-handed neutrinos, consistent with neutrino masses via see-saw and leptogenesis. We describe a mechanism for generating Yukawa couplings in this model and also discuss the low-energy phenomenology. Interestingly, the new gauge boson could explain the recent hints of lepton universality violation at LHCb, with a gauge coupling that remains perturbative up to the Planck scale. Finally, we discuss more general U(1) symmetries and show that there exist only two classes of vectorial U(1) that are both consistent with leptogenesis and remain phenomenologically viable at low-energies.
Las exposiciones de obras tecnológicas actuales corren el riesgo de invalidar las producciones críticas, radicales o disidentes al ser cooptadas por la espectacularidad de sus recursos técnicos. Esto ...es particularmente grave en el contexto latinoamericano donde el acceso a las tecnologías es causa muchas veces de exclusiones y desigualdades de todo tipo. A partir de la recepción crítica del futurismo por parte de intelectuales como Vicente Huidobro, César Vallejos y José Carlos Mariátegui, nos proponemos reflexionar sobre las proyecciones particularmente problemáticas de las creaciones tecnológicas contemporáneas en contextos expositivos hi-tech.
A geometric formulation of Higgs Effective Field Theory (HEFT) is presented. Experimental observables are given in terms of geometric invariants of the scalar sigma model sector such as the curvature ...of the scalar field manifold M. We show how the curvature can be measured experimentally via Higgs cross-sections, WL scattering, and the S parameter. The one-loop action of HEFT is given in terms of geometric invariants of M. The distinction between the Standard Model (SM) and HEFT is whether M is flat or curved, and the curvature is a signal of the scale of new physics.
The anomalous dimensions of dimension-six operators in the Standard Model Effective Field Theory (SMEFT) respect holomorphy to a large extent. The holomorphy conditions are reminiscent of ...supersymmetry, even though the SMEFT is not a supersymmetric theory.
The one-loop renormalization of the action for a set of Dirac fermions and a set of scalars spanning an arbitrary manifold coupled via Yukawa-like and gauge interactions is presented. The computation ...is performed with functional methods and in a geometric formulation that preserves at all stages the symmetries of the action. The result is then applied to Higgs effective field theory to obtain the renormalization group evolution. In the standard model limit of this effective field theory the renormalization group evolution equations collapse into a smaller linearly independent set; this allows to probe the dynamics of the scalar discovered at LHC via de-correlations in the running of couplings.
Trait-based ecology predicts that evolution in high-resource agricultural environments should select for suites of traits that enable fast resource acquisition and rapid canopy closure. However, crop ...breeding targets specific agronomic attributes rather than broad trait syndromes. Breeding for specific traits, together with evolution in high-resource environments, might lead to reduced phenotypic integration, according to predictions from the ecological literature. We provide the first comprehensive test of these hypotheses, based on a trait-screening programme of 30 herbaceous crops and their wild progenitors. During crop evolution plants became larger, which enabled them to compete more effectively for light, but they had poorly integrated phenotypes. In a subset of six herbaceous crop species investigated in greater depth, competitiveness for light increased during early plant domestication, whereas diminished phenotypic integration occurred later during crop improvement. Mass-specific leaf and root traits relevant to resource-use strategies (e.g. specific leaf area or tissue density of fine roots) changed during crop evolution, but in diverse and contrasting directions and magnitudes, depending on the crop species. Reductions in phenotypic integration and overinvestment in traits involved in competition for light may affect the chances of upgrading modern herbaceous crops to face current climatic and food security challenges.
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