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Time: 2pm
Location: 2N36
Title: TBA

Time: 2pm
Location: 2N36
Title: TBA

Time: 1:30 pm
Location: 4N12
Title: TBA

Time: 1:30pm
Location: 4N12
Title: TBA

Time: 2pm
Location: 2N36
Title: TBA

Time: 2pm
Location: 2N36
Title: TBA

Time: 1:30pm
Location: 4N12
Title: TBA

Time: 2pm
Location: 2N36
Title: TBA

Time: 2pm
Location: 2N36
Title: Some new mechanisms for baryogenesis

Abstract: There is more matter than antimatter in the universe, and the origin of this asymmetry is still a mystery. The asymmetry can be generated dynamically in the early universe in a process referred to as baryogenesis but the standard model is not able to produce the amount observed. This is one hint that there is physics beyond the standard model. In this talk, I will present two new baryogenesis mechanisms, one using scalar-tensor theories and the other using Lorentz violating theories. I will discuss their phenomenology, and observational consequences, and show that they are able to produce the amount of matter that we observe in the universe today.

Time: 2pm
Location: 2N36
Title: Bit threads in space and time

Abstract: Bit threads are a reformulation of the Ryu-Takayanagi holographic entanglement entropy formula that offer several conceptual advantages over the standard minimal-surface formulation. After briefly reviewing the basic bit thread story, I will explain how to extend them in three interesting directions. First, I will show how bit threads offer a novel proof of the "monogamy of mutual information" inequality for holographic entanglement entropies, and how the proof suggests a very specific entanglement structure for holographic states. Second, I will explain how to include higher-derivative corrections. Finally, I will explain how to make bit threads covariant, reproducing the Hubeny-Rangamani-Takayanagi formula.

Time: 2pm
Location: 4N12
Title: Geometric engineering on flops of length two

Abstract: Type IIA on the conifold is a prototype example for engineering QED with one charged hypermultiplet. In type IIB, a single D3-probe at the singularity sees an abelian quiver gauge theory. The geometry admits a flop of length one. In this talk, we study the next generation of geometric engineering on singular geometries, namely flops of length two such as Laufer’s example, which we affectionately think of as the conifold 2.0. IIA on the latter geometry gives QED with higher charge states. In IIB, even a single D3-probe gives rise to a nonabelian quiver gauge theory. We study this class of geometries explicitly by leveraging their quiver description, showing how to parametrize the exceptional curve, how to see the flop transition, and how to find the noncompact divisors intersecting the curve.

Time: 2pm 
Location: 2N36
Title: Naturally Stabilizing the Weak Scale without Partners
 
We generalize and adapt Veltman's condition to create a framework which naturally addresses the little hierarchy problem.  The resulting class of models is economical and ensures a minimum amount of fine-tuning for the bare Standard Model Higgs mass.  To demonstrate this framework, we provide a model with an extended Higgs sector and a top Yukawa coupling that is no longer unity.  The latter alleviates the largest radiative corrections to the Higgs mass.  The former features significant dimension-full couplings that generate, at best, logarithmic corrections to the Higgs masses.  The dimensionless couplings are small and do not generate large quadratic divergences or produce Landau poles.  We find the cutoff can be raised to 5-7 TeV without significant fine-tuning for a large region of parameter space.  We briefly discuss some of the phenomenology of the model and emphasize the importance of future $\bar{t}t h$ measurements. 

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