LHC Lunch
Speaker:
Title:
Host: Markus Luty
Room: 432
Abstract:
User:
High-Energy Seminars
Time:
5:30am - 6:30am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
Joint Theory Seminar
Speaker: Josh Cooperman
Title: Renormalization of Entanglement Entropy and the Gravitational Effective Action
Host: Luty
Room: 432
Abstract: The entanglement entropy associated with a spatial boundary in quantum field theory is UV divergent, its leading term being proportional to the area of the boundary. Callan and Wilczek proposed a geometrical prescription for computing this entanglement entropy as the response of the gravitational effective action to a conically singular metric perturbation. I demonstrate that the Callan-Wilczek prescription is rigorously justified for a particular class of quantum states, each expressible as a Euclidean path integral. I then show that the entanglement entropy is rendered UV finite by precisely the counterterms required to cancel the UV divergences in the gravitational effective action. In particular, the leading contribution to the entanglement entropy is given by the renormalized Bekenstein-Hawking formula. These results apply to a general quantum field theory coupled to a fixed background metric, holding for arbitrary entangling surfaces in any dimension, to all orders in perturbation theory in the quantum fields, and for all subleading UV divergent terms in the entanglement entropy. I also reconcile these results on the entanglement entropy with the existing literature, compare them to the Wald entropy, and speculate on their interpretation and implication.
User:
High-Energy Seminars
Time:
9:00am - 10:00am
Send Reminder:
Yes - 1 day 8 hour 0 minutes before start
Description:
HE Seminar
Speaker:
Title:
Host:
Room: 285
Abstract:
User:
High-Energy Seminars
Time:
4:10am - 5:10am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
LHC Lunch
Speaker: Rachel Houtz
Title: Finding Natural SUSY at the LHC
Host: Markus Luty
Room: 432
Abstract:
User:
High-Energy Seminars
Time:
5:30am - 6:30am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
Joint Theory Seminar
Speaker: Jessie Shelton
Title: Hunting Asymmetric Stops
Host: John Terning
Room: 432
Abstract:
User:
High-Energy Seminars
Time:
8:00am - 9:00am
Send Reminder:
Yes - 1 day 8 hour 0 minutes before start
Description:
HE Seminar
Speaker:
Title:
Host:
Room: 285
Abstract:
User:
High-Energy Seminars
Time:
4:10am - 5:10am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
LHC Lunch
Speaker:
Title:
Host: Markus Luty
Room: 432
Abstract:
User:
High-Energy Seminars
Time:
8:00am - 9:00am
Send Reminder:
Yes - 1 day 8 hour 0 minutes before start
Description:
HE Seminar
Speaker: Norihiro Tanahashi (UC Davis)
Title: Horizon instability of an extreme Reissner-Nordstrom black hole
Host:
Room: 285
Abstract: Recently, a novel instability was found for a massless scalar field on an extreme Reissner-Nordstrom black hole. This instability is a purely classical process, and it makes a part of energy-momentum tensor of the scalar field discontinuous on the horizon at late time. We show that a similar instability occurs also for a massive scalar field and for coupled linearized gravitational and electromagnetic perturbations. These instabilities are intimately related to conserved quantities constructed from perturbative fields. We analytically show the existence of instability based on these quantities when possible, and also conduct numerical analysis to examine more general cases. We discuss the physical mechanism and implications of this instability, and also argue the final fate of the system after nonlinear effects set in.
User:
High-Energy Seminars
Time:
4:30am - 5:45am
Description:
Speaker: Jiang Yun
Title: 125 GeV Higgs Bosons in the 2HDM
Host: Markus Luty
Room: 432,
Abstract: The current Higgs boson data at 125 GeV state appears to
exhibit a substantial excess in the di-photon final state, whereas a
more or less SM-like rate is observed in the ZZ decaying to four
lepton channel. Beyond the SM, the two-Higgs-doublet model (2HDM)
containing a second Higgs doublet is one of the simplest extensions.
We examine the maximum Higgs signal enhancements that can be achieved
in the 2HDM (when either a single Higgs or multiple Higgses have
mass(es) near 125 GeV). In general, the constraints of vacuum
stability, unitarity and perturbativity play the key role in
restricting possibilities for signal enhancement. The Type II model
allows for an enhancement in the di-photon rate (relative to the SM)
of the order of 2-3 but associated with an even larger ZZ signal, a
situation disfavored by the LHC observations. In contrast, the maximal
value for the di-photon signal in the Type I model can reach the order
of 1.3 for which the ZZ signal is of order 1, both being consistent
with the current data.
User:
High-Energy Seminars
Time:
4:10am - 5:10am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
LHC Lunch
Speaker: Markus Luty
Title: Are Black Holes Firewalls?
Host: Markus Luty
Room: 432
Abstract: I will discuss the "firewall" paper arXiv:1207.3123.
User:
High-Energy Seminars
Time:
5:30am - 6:30am
Send Reminder:
Yes - 0 days 4 hour 0 minutes before start
Description:
Joint Theory Seminar
Speaker: Joe Polchinski
Title: Black Holes: Complementarity or Firewalls?
Host: Markus Luty
Room: 432
Abstract: The black hole information paradox presents a sharp conflict between quantum mechanics and locality. AdS/CFT duality indicates that it is locality gives way, but the details have never been clear. Recent developments have sharpened the question, in that it appears that three widely believed statements cannot all be true: (i) the Hawking radiation is in a pure state, (ii) the information carried by the radiation is emitted from the region near the horizon, with low energy effective field theory valid outside the horizon, and (iii) the infalling observer encounters nothing unusual at the horizon.
User:
High-Energy Seminars
Time:
8:00am - 9:00am
Send Reminder:
Yes - 1 day 8 hour 0 minutes before start
Description:
HE Seminar
Speaker: Lindley Winslow
Title: A Revolution? Neutrinos and Nanotechnology
Host: Svoboda
Room: 285
Abstract:The last decade has seen a revolution in our understanding of the most mysterious of the Standard Model particles, the neutrino, and this last year has been no exception. In the last year, we have seen exciting results from both double beta decay experiments and experiments measuring the last mixing angle theta_13. For the most part, the detectors responsible for these measurements use Cerenkov and scintillation light to detect neutrino interactions. The wavelength of this light is matched to the peak efficiency of photo-multiplier tubes. This technique has been finely tuned over the last decades, but no great leaps forward in efficiency have been achieved. Nanotechnology may hold the key to improving both scintillators and photo-detectors. In this talk, I will focus on one particular technology, semiconducting nanocrystals known as quantum dots, and their unique optical properties. I will discuss how their use could enhance the capabilities of new photo-detection technology, and address the needs of the next-generation neutrino experiments.
4:10am» LHC Lunch