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Time: 1:30pm
Location: 2C8

Title: New Physics from Standard Model Measurements
 
 
Abstract: We traditionally look for new physics at colliders by trying to separate signals from Standard Model (SM) backgrounds.  This approach has led to striking constraints from the LHC, but no discovery of new physics beyond the SM.  In this talk I will highlight the alternate approach of using precision measurements of SM processes to search for subtle effects of new physics that is otherwise hidden from traditional searches.  I will highlight examples where precise measurements of top quark, lepton, and jet production can be used to look for new physics.  

Time: 2pm
Location: 2N36
 
Title: Cosmology of a Fine-Tuned SUSY Higgs.
 
  
Abstract: I will discuss some work in progress that explores whether a mildly fine-tuned Higgs boson, as in (mini-)split supersymmetry, can have interesting or observable cosmological consequences. As moduli fields oscillate, the Higgs can respond and perhaps acquire very large values along a D-flat direction. Possible consequences involve a burst of gravitational wave production and an altered estimate of the number of e-folds of inflation.

Time: 2pm
Location: 2N36

Title: BMS invariant fluids

Abstract: The Bondi-van der Burg-Metzner-Sachs (BMS) group is the asymptotic symmetry group of asymptotically flat spacetime.  It is related to flat gravity in the same way that the conformal group is related to anti de Sitter gravity.  However, while the conformal group is well known throughout field theory, the BMS group is rather mysterious.  We show that the BMS group is closely related to infinite dimensional symmetry groups governing fluid dynamics.  We use a relationship between gravitating systems and lower dimensional fluids on their boundaries to give a new derivation of the BMS group in three spacetime dimensions.

Time: 2pm
Location: 2N36
 
Title: Entanglement at a Scale and Recovery Maps
 
Abstract:
I discuss the amount of information in quantum field theory states reduced to a region, that cannot be recovered from its subregion density matrices. One can reconstruct the density matrix from its subregions using recovery maps. The vacuum of a conformal field theory is a quantum Markov state and the fixed point of both transformations. I define the entanglement of scaling as a measure of entanglement at a scale, and mention connections with C-theorems proofs in 2, 3 and 4 dimensions.

Time: 1:30pm
Location: 4N12
Title: Composite Higgses

Time: 2pm
Location: 2N36

Title: What Can Cosmology Tell Us About Gravity?
 
 Abstract: I will review the current status and future prospects of testing theories of gravity using data from large scale structure surveys. I will then discuss certain aspects of the so-called model-independent tests of dark energy and modified gravity. One is the choice of priors when trying to constrain unknown functions of redshift. Another is the physical interpretation of such tests and their implications for particular types of modified gravity theories.

Time: 12 pm
Location: 4N12
Title: Aretakis Charges and Asymptotic Null Infinity

Abstract: We construct a relation between the Aretakis charge of any extreme black hole and the Newman-Penrose charge. This is achieved by constructing a conformal correspondence between extreme black holes and what we call weakly asymptotically flat space-times. Under this correspondence the Newman-Penrose charge of the weakly asymptotically flat space-time maps on to the Aretakis charge of the extreme black hole. Furthermore, we generalise the conformal isometry displayed by the extreme Reissner-Nordström solution to a novel conformal symmetry that acts within a class of static STU supergravity black holes.

Time: 1:30pm
Location: 4N12
Title: Magnetohydrodynamics from generalised global symmetries: effective field theory and holography

Time: 2pm
Location:2N36
 
Title: Spinning Cosmology

 Abstract: We study the signatures left by new light particles with spin on the primordial cosmological fluctuations. In distinction from the pure de Sitter background, where fields with spin have to be massive enough to satisfy the Higuchi bound, the inflation allows to host spinning particles that are parametrically lighter than the expansion rate. I introduce the description of the particles with spin in the context of the Effective Field Theory of Inflation and discuss the main signatures left by such particles on the primordial fluctuations.

Time: 2pm
Location: 2N36
 
Title: Equivalence principle in scalar-tensor theories

 Abstract: We study the question of whether the equivalence principle holds for extended objects moving on cosmological backgrounds in modified gravity theories. We do so within the framework of effective field theory of dark energy focusing in particular on the subclass corresponding to the Horndeski theories. These are the most general second order scalar-tensor theories with non-linear derivative self-interactions allowing the Vainshtein screening mechanism to operate on small scales. We show how the approximate shift symmetry of the action, together with the special derivative structure of the scalar self-interactions insures that the equivalence principle is obeyed for screened extended objects with negligible self-gravitational energy. We comment on the possibility of extending the argument to the case of black holes.

Time: 2pm
Location: 2N26

Title: Topological sectors, supersymmetric localization, and holography

Time: 1:30pm
 
Location: 4N12
 
Title: Many-body localization: breakdown of thermalization in quantum matter

Abstract: Until recently interacting many-particle systems governed by the laws of quantum mechanics were assumed to eventually reach thermal equilibrium, being described by equilibrium statistical physics. Rapid developments in theory and experiments in the last decade have established a phase of matter where this assumption is false, due to a phenomenon known as many-body localization (MBL). In this phase, the system undergoing unitary time dynamics retains memory of the initial state in local observables for infinitely long times. I will give an overview of the theoretical and experimental progress in this growing field at the intersection of condensed matter physics, quantum information science and atomic physics.
I will describe the emergent integrability of the MBL phase which gives rise to area-law entanglement for the full many-body spectrum of eigenstates. This structure of the eigenstates allows for an efficient description of the system using shallow quantum circuits. MBL also gives rise to novel forms of quantum phase transitions even in states at finite energy densities. I will conclude with some of the open questions in this field.

Time: 2pm
Location: 2N36

Title: A toy model of axion gauge field inflation
 
 Abstract: We present a toy model of an axion gauge field inflation scenario that yields viable density and gravitational wave spectra. The scenario consists of an axionic inflaton in a steep potential that is effectively flattened by a coupling to a collection of non-Abelian gauge fields. The model predicts a blue-tilted gravitational wave spectrum that is dominated by one circular polarization, resulting in unique observational targets for cosmic microwave background (CMB) and gravitational wave experiments. The handedness of the gravitational wave spectrum is incorporated in a model of leptogenesis through the axial-gravitational anomaly. In order to explain the matter-antimatter asymmetry of the Universe, we obtain an approximate lower bound on the tensor-to-scalar ratio that is within reach of current CMB experiments.

Time: 1:30pm

Location: 4N12

Title: Digging Deeper for New Physics in the LHC Data

Time: 2pm

Location: 2N36

Title: Thermal Equivariance and its applications

Time: 2pm
Location: 2N36
Title: Markovian property of vacuum state and the a-theorem

Time: 2pm
 
Location: 2N36
 
Title: Generalized Parallelizable Spaces, Consistent Truncations and DualitiesAbstract: While only three sphere, S^1, S^3 and S^7, are parallelizable,  it was recently shown that all spheres are generalized parallelizable. In addition to its beautiful mathematical structure, this extended notion of parallelizability allows to identify certain maximal gauged supergravities as consistent truncations of 10/11D supergravity. In this talk, I present the first systematic construction of generalized parallelize spaces and demonstrate how this string theory inspired concept captures T-duality in a natural way.

Time: 1:30pm
Location: 4N12
Title:  Applications of the Average Null Energy Condition
Abstract:  Local energy conditions are key hypothesis in many classical results in general relativity.  In quantum theory these local energy conditions are invalidated due to quantum fluctuations.  Nevertheless a weaker condition, the so-called average null energy condition still holds in quantum field theory.  I will explain how this this condition constrains the data of conformal field theories such as operator product coefficients and scaling dimensions.

Time: 10am - 6:30pm
Location: 4N12
Webpage: https://web.sas.upenn.edu/penn-jcppm/

Time: 2pm
Location: 2N36
 
TITLE: The re-emergance of spontaneously broken space-time symmetries without Goldstones or Inverse Higgs
 
ABSTRACT: In this talk I will discuss how broken space-time symmetries can emerge in the IRafter being spontaneously broken in the UV, even though there may be no Goldstonebosons. Given that there has been a large body of work on trying to get space-timesymmetry (e.g. Lorentz) to be emergent in the IR via an RG attractive basin, this may seemlike a very surprising and non-generic result. However, I will show that in the context ofFermi liquid theory it is quite natural, and even required to preserve Fermi liquid behavioras the existence of Goldstone bosons (in this case they would be non-derivative coupled) would lead to shortened life-times for quasi-particles. I will also consider the spontaneous breaking of Schrodingersymmetry whose emergence (with no dilaton) in the IR leads to very strong constraintson Fermi liquids at unitarity.