Benjamin Koch

Black hole remnants at the LHC

Within the scenario of large extra dimensions, the Planck scale is lowered to values soon accessible. Among the predicted effects, the production of TeV mass black holes at the LHC is one of the most exciting possibilities. Though the final phases of the black holes evaporation are still unknown, the formation of a black hole remnant is a theoretically well motivated expectation. We analyze the observables emerging from a black hole evaporation with a remnant instead of a final decay. We show that the formation of a black hole remnant yields a signature which differs substantially from a final decay. We find the total transverse momentum of the black hole event to be significantly dominated by the presence of a remnant mass providing a strong experimental signature for black hole remnant formation.

BTZ black hole assuming running couplings

In the present work a generalization of the BTZ black hole is studied, for the case of scale dependent couplings. One starts by using the effective action for scale dependence couplings to get a generalization of the Einstein field equations. Self consistent solutions for lapse function, cosmological coupling and Newtons coupling are found. The effect of scale dependent couplings with respect to the classical solution is shown. Moreover, asymptotic behavior as well as thermodynamic properties were investigated. Finally, an alternative way to get the scale dependent Newton coupling, from the so-called Null Energy Condition is presented.

Collisions of spinning massive particles in a Schwarzschild background

It is known that the center-of-mass energy of the collision of two massive particles following geodesics around a black hole presents a maximum. The maximum energy increases when the black hole is endowed with spin, and for a maximally rotating hole this energy blows up, offering, in principle, a unique probe of fundamental physics. This work extends the latter studies by considering that the colliding particles possess intrinsic angular momentum (spin), described by the Hanson–Regge–Hojman theory of spinning particles. By analyzing planar trajectories of spinning particles around non-rotating black holes, a significant increase of the invariant collision energy is found. Radial turning points, causality constraints, and limitations of the theory are discussed.

Scale Setting for Self-consistent Backgrounds

Departamento de F´isica,Universidad T´ecnica Federico Santa Mar´ia;Casilla 110-V, Valpara´iso, Chile;(Dated: September 17, 2014)The quest for findingself-consistent background solutions in quantum field theory is closely relatedto the way one decides to set renormalization scale k. This freedom in the choice of the scale settingcan lead to ambiguities and conceptual inconsistencies such as the non-conservation of the stress-energy tensor. In this paper a setting for the “scale-field” at the level of effective action proposed,which avoids such inconsistencies by construction. The mechanism and its potential is exemplifiedfor scalar φ

Gravitino dark matter and neutrino masses in partial split supersymmetry

Partial Split Supersymmetry with bilinear R-parity violation allows to reproduce all neutrino mass and mixing parameters. The viable dark matter candidate in this model is the gravitino. We study the hypothesis that both possibilities are true: Partial Split Supersymmetry explains neutrino physics and that dark matter is actually composed of gravitinos. Since the gravitino has a small but non-zero decay probability, its decay products could be observed in astrophysical experiments. Combining bounds from astrophysical photon spectra with the bounds coming from the mass matrix in the neutrino sector we derive a stringent upper limit for the allowed gravitino mass. This mass limit is in good agreement with the results of direct dark matter searches.

A scale dependent black hole in three-dimensional space–time

Scale dependence at the level of the effective action is a generic result of quantum field theory. Allowing for scale dependence of the gravitational couplings leads to a generalization of the corresponding field equations. In this work, those equations are solved by imposing the null energy condition in three-dimensional space time with stationary spherical symmetry. The constants of integration are given in terms of the classical BTZ parameters plus one additional constant, that parametrizes the strength of the scale dependence. The properties such as asymptotics, horizon structure, and thermodynamics are discussed. It is found that the black hole entropy shows a remarkable transition from the usual area~law to an area~

Extracorporeal Virus Elimination for the Treatment of Severe Ebola Virus Disease - First Experience with Lectin Affinity Plasmapheresis

times

Black hole solutions for scale-dependent couplings: the de Sitter and the Reissner–Nordström case

~radius law.

Constraints to Dark Matter from Inert Higgs Doublet Model

Therapeutic options for Ebola virus disease (EVD) are currently limited to (1) best supportive care, and (2) evolving virus-specific therapies, resulting from decades of analyzing one of the worlds deadliest diseases. Supportive care ranges from oral or intravenous rehydration therapy and anti-emetics in developing countries to much more extensive life-support interventions in resource-rich countries. Current EVD-specific therapies attempt to either interfere with the earliest steps of viral replication or to elicit a strong immune response against the virus. An entirely new approach is the extracorporeal elimination of viruses and viral glycoproteins by lectin affinity plasmapheresis. Herein, we report for the first time the successful and safe use of lectin affinity plasmapheresis in a patient with severe Ebola virus disease.

Renormalization group and black hole production in large extra dimensions

Allowing for scale dependence of the gravitational couplings leads to a generalization of the corresponding field equations. In this work, these equations are solved for the Einstein–Hilbert and the Einstein–Maxwell case, leading to generalizations of the (Anti)-de Sitter and the Reissner–Nordstrom black holes. These solutions are discussed and compared to their classical counterparts.