# Rethinking Quantum Field Theory

27-30 September 2016
DESY Hamburg
Europe/Berlin timezone
Home > Contribution List

## Contribution List

Displaying 96 contributions out of 96
Session: Plenary Session
Combining insights from different branches of physics we will present a rich set of dualities in 2+1 dimensions
Presented by Nathan SEIBERG on 28 Sep 2016 at 12:20 PM
Session: Parallel Session: Particle Phenomenology 1b - BSM
Track: Particle Phenomenology
Presented by Jan HEISIG on 28 Sep 2016 at 2:20 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
In this work, we develop a method to compare results from various direct detection experiments without making assumptions on the velocity distribution of the dark matter particles in the Solar System. Furthermore, we consider the particular case when one of the experiments reports a positive signal, and we apply our method to investigate the compatibility of the DAMA claim with the null searches f ... More
Presented by Andreas RAPPELT on 28 Sep 2016 at 3:15 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
The discovery of the Higgs boson puts a severe constraint on the available parameter space in any SUSY model. In the MSSM, a 125 GeV Higgs together with relatively light stops needs a very large stop mixing, therefore large trilinear terms in the scalar potential. Those are known to destabilize the electroweak ground state and induce a true vacuum in association with squark vevs. Previous analyses ... More
Presented by Wolfgang Gregor HOLLIK on 29 Sep 2016 at 2:15 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
A positive representation for an arbitrary complex, gaussian weight is derived and used to construct a statistical formulation of gaussian path integrals directly in the Minkowski time. The positivity of Minkowski weights is achieved by doubling the number of real variables. The continuum limit of the new representation exists only if some of the additional couplings tend to infinity and are tuned ... More
Presented by Jacek WOSIEK on 29 Sep 2016 at 5:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Black holes possess a wide range of rather peculiar properties, many of them in connection with their ability to process, store and release information. I explore the possibility that the physical origin of these properties is quantum criticality. To this end, I will demonstrate that simple Bose condensates exhibit a plethora of black hole like properties. This includes trapping, baldness, evapora ... More
Presented by Dr. Nico WINTERGERST on 29 Sep 2016 at 4:20 PM
Session: Plenary Session
A great part of the problem of understanding the structure of the space of quantum field theories (QFT) is arguably reduced to the one of classifying possible critical points. In this picture, the theories with mass scales are obtained by perturbing critical points and following the renormalization group (RG) trajectories. However, interestingly, in the flow not all critical points can be joined w ... More
Presented by Marina HUERTA on 27 Sep 2016 at 4:40 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We investigate the collinear behavior of tree level amplitudes in several theories using their CHY (Cachazo-He-Yuan) representation. We obtain the leading and subleading orders of the adjacent collinear limit and ask the question whether universality is present and how Einstein-Yang-Mills amplitudes emerge by checking specific identities due to Stieberger and Taylor.
Presented by Mr. Wadim WORMSBECHER on 29 Sep 2016 at 2:15 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
The recent detection by Advanced LIGO of gravitational waves (GW) from the merging of a binary black hole system sets new limits on the merging rates of massive primordial black holes (PBH) that could be identified to the dark matter in the Universe. If PBH are regrouped in clusters with a similar density to the one observed in ultra-faint dwarf galaxies, merging rates are comparable to aLIGO ex ... More
Presented by Dr. Sebatien CLESSE on 28 Sep 2016 at 2:15 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
Presented by Daniel SCHMEIER on 29 Sep 2016 at 3:00 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We study maximally supersymmetric solutions of all gauged or deformed supergravity theories in D≥3 space-time dimensions. For vanishing background fluxes the space-time background has to be either Minkowski or anti-de Sitter. We derive a simple criterion for the existence of solutions with non-trivial fluxes and determine all supergravities that satisfy it. We show that their solutions coincide ... More
Presented by Mr. Severin LÜST on 28 Sep 2016 at 3:20 PM
Session: Plenary Session
I will review some exact results about the coupling constant dependence of the chiral ring in four dimensional N=2 theories.
Presented by Kyriakos PAPADODIMAS on 28 Sep 2016 at 10:30 AM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We construct zero-curvature representations for the equations of motion of a class of sigma-models with complex homogeneous target spaces, not necessarily symmetric. We show that in the symmetric case the proposed flat connection is gauge-equivalent to the conventional one.
Presented by Dr. Dmitri BYKOV on 28 Sep 2016 at 2:20 PM
Session: Plenary Session
In this talk we will give an overview of recent results obtained from the bootstrap approach to CFTs. We will discuss both analytical and numerical results, including for supersymmetric theories. We identify several promising directions for further research
Presented by Balt VAN REES on 30 Sep 2016 at 9:40 AM
Session: Parallel Session: Particle Phenomenology - QCD & BSM
Track: Particle Phenomenology
Quantum Chromodynamics (QCD) in non-integer d = 4 − 2e space-time dimensions possesses a nontrivial critical point where the theory enjoys exact scale and conformal invariance. As consequence there are three symmetry generators that commute with the renormalization group equation for composite operators. The resulting constraints allow to reconstruct full evolution kernels in physical (integer) ... More
Presented by Mr. Matthias STROHMAIER on 29 Sep 2016 at 2:00 PM
Session: Plenary Session
I will discuss how gravity scattering amplitudes of many different gravitational theories can be obtained from various gauge theories through a double-copy procedure. The basic idea goes back to the old relation between open and closed strings, but I will argue that gravity being the double copy of two gauge theories is a more general notion. I will present new striking examples of gravity theorie ... More
Presented by Henrik JOHANSSON on 29 Sep 2016 at 9:40 AM
Session: Parallel Session: Particle Phenomenology - QCD & BSM
Track: Particle Phenomenology
In the Wilson formulation, lattice gauge theories with compact gauge group are confining, at least in the strong coupling limit. In addition, the ground state usually preserves discrete symmetries such as translational and charge conjugation symmetry. In this talk, we consider generalized lattice gauge theories: quantum link models and self-adjoint extensions of Wilson-type theories in (2+1)-dime ... More
Presented by Dr. Debasish BANERJEE on 29 Sep 2016 at 2:20 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
Presented by Jonas LINDERT on 28 Sep 2016 at 2:00 PM
Session: Parallel Session: Particle Phenomenology 1b - BSM
Track: Particle Phenomenology
Presented by Kechen WANG on 28 Sep 2016 at 2:40 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Within the next few years cosmological structure formation will be probed in greater detail than ever before by new and very large surveys, most notably EUCLID and LSST. While this opens great possibilities for probing for example dark energy and the mass of neutrinos, it also puts very stringent requirements on theoretical calculations of cosmological observables, such as the matter power spectr ... More
Presented by Maria ARCHIDIACONO on 29 Sep 2016 at 2:45 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We study the higher-spin gauge theory in six-dimensional anti-de Sitter space AdS6 that is based on the exceptional Lie superalgebra F(4). The relevant higher-spin algebra was constructed in arXiv:1409.2185 [hep-th]. We determine the spectrum of the theory and show that it contains the physical fields of the Romans F(4) gauged supergravity. The full spectrum consists of an infinite tower of unitar ... More
Presented by Evgeny SKVORTSOV on 28 Sep 2016 at 2:00 PM
Session: Parallel Session: Particle Phenomenology - QCD & BSM
Track: Particle Phenomenology
A light stop with mass almost degenerate with the lightest neutralino has important implications on naturalness and dark matter relic abundance, and is hard to search at colliders. In this paper, we study the potential of searching for such stop particles at the LHC from sbottom decays, focusing on two channels with final states 2l+met and 1b1l+met. We found that, if the lightest sbottom has ma ... More
Presented by Dr. Jiayin GU on 29 Sep 2016 at 3:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Interactions that manifest themselves as lepton number violating processes at low energies in combination with sphaleron transitions typically erase any pre-existing baryon asymmetry of the Universe. We demonstrate in a model independent approach that the observation of neutrinoless double beta decay would impose a stringent constraint on mechanisms of high-scale baryogenesis, including leptogen ... More
Presented by Dr. Julia HARZ on 28 Sep 2016 at 5:30 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
If the Standard Model Yukawa couplings varied in the early universe and started with order one values before electroweak symmetry breaking, the CP violation associated with the CKM matrix could be the origin of the matter-antimatter asymmetry. The large effective Yukawa couplings which lead to the enhanced CP violation can also help in achieving a strong first-order electroweak phase transition. I ... More
Presented by Dr. Iason BALDES on 28 Sep 2016 at 4:45 PM
Session: Parallel Session: Particle Phenomenology - QCD
Track: Particle Phenomenology
We present a phenomenological study of 4-jet production, calculated within high-energy factorization, including both contributions from single-parton and double-parton scattering. High-energy factorization causes a momentum inbalance in the final state, allowing for the description of observables at tree-level that would require next-to-leading order precision in collinear factorization. The ... More
Presented by Andreas VAN HAMEREN on 28 Sep 2016 at 4:35 PM
Session: Plenary Session
We consider weakly-coupled theories of massive higher-spin particles. This class of models includes, for instance, tree-level String Theory and Large-N Yang-Mills theory. The S-matrix in such theories is a meromorphic function obeying unitarity and crossing symmetry. We discuss the unphysical high-energy fixed imaginary angle scattering regime. We expect the amplitude to be universal and exponenti ... More
Presented by Zohar KOMARGODSKY on 28 Sep 2016 at 9:50 AM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
In this talk, I'll show how updated information from gamma-rays experiments constrain the spectrum of the galactic sources previously detected by the Milagro collaboration. I'll show the number of through-going muons expected from these sources at the IceCube detector and I'll discuss the statistical significance of each source as a function of the detector running time. Moreover, I'll show al ... More
Presented by Dr. Viviana NIRO on 28 Sep 2016 at 4:30 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We consider possible discretizations for a gauge-fixed Green-Schwarz action of Type IIB superstring. We use them for measuring the action, from which we extract the cusp anomalous dimension of planar N=4 SYM as derived from AdS/CFT, as well as the mass of the two AdS excitations transverse to the relevant null cusp classical string solution. For both the observables, we find a good agreement for l ... More
Presented by Dr. Lorenzo BIANCHI on 29 Sep 2016 at 4:45 PM
Session: Hertz Lecture
Presented by Nathan SEIBERG on 29 Sep 2016 at 5:30 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Current Higgs boson and top quark data favour metastability of our vacuum which raises questions as to why the Universe has chosen an energetically disfavoured state and remained there during the primordial dynamics. In this talk I will point out that allowing a simple Higgs-inflaton coupling can explain why the Higgs ended up in the electroweak vacuum after inflation. I will show that this coupli ... More
Presented by Mr. Marco ZATTA on 29 Sep 2016 at 3:15 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
In this talk, I will describe the connection between the high-energy limit of the six-gluon scattering amplitude in N=4 super Yang-Mills theory and a certain class of single-valued polylogarithmic functions. While the evaluation of the six-gluon amplitude to high loop orders in general kinematics is a very difficult problem, the amplitude in the multi-Regge regime is governed by a dispersion-like ... More
Presented by Martin SPRENGER on 29 Sep 2016 at 2:50 PM
Session: Plenary Session
In this talk I will give an overview of various developments in integrability within the AdS/CFT correspondence emphasizing novel directions and setups. I will also point out some outstanding questions.
Presented by Romuald JANIK on 29 Sep 2016 at 9:00 AM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
Presented by Tania ROBENS on 28 Sep 2016 at 3:20 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
I will introduce the basic concepts of Large-Charge Perturbation Theory (LCPT) in d+1 space-time dimensions. Given a Quantum Field Theory with a globally conserved charge Q, LCPT aims at providing analytic insight to sectors, which remain inaccessible via ordinary perturbative methods, but where Q is assumed to be large. To this end, the scalar O(2) model with $\phi^N$ self-interaction will be i ... More
Presented by Mr. Orestis LOUKAS on 29 Sep 2016 at 2:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
The extension of the Standard Model by heavy right-handed neutrinos can simultaneously explain the observed neutrino masses via the seesaw mechanism and the baryon asymmetry of the Universe via leptogenesis. If the mass of the heavy neutrinos is below the electroweak scale, they may be found at LHCb, BELLE II, the proposed SHiP experiment or a future high-energy collider. In this mass range, the b ... More
Presented by Mr. Juraj KLARIĆ on 28 Sep 2016 at 4:15 PM
Session: Parallel Session: Particle Phenomenology 1b - BSM
Track: Particle Phenomenology
Combining Pati-Salam (PS) and flavour symmetries in a renormalisable setup, we devise a scenario which produces realistic masses for the charged leptons. Flavour-symmetry breaking scalar fields in the adjoint representations of the PS gauge group are responsible for generating different flavour structures for up- and down-type quarks as well as for leptons. The model is characterised by new ... More
Presented by Paul MOCH on 28 Sep 2016 at 3:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
A tremendous experimental effort is underway with the goal of delivering the first non- gravitational detection of dark matter (DM). Indeed, despite its huge abundance, very little is known about the true nature of DM, and the community is eager for new and innovative ideas able to finally pin down its properties. In this talk, I shall review how cross-correlations of astrophysical and cosmologi ... More
Presented by Dr. Stefano STEFANO CAMERA on 28 Sep 2016 at 2:30 PM
Session: Plenary Session
The locality of fundamental interactions and the nonlocal character of quantum correlations are reconciled in the framework of algebraic quantum field theory. The theory is based on the concept of local fields which are mathematically characterized as natural tranformations between suitable functors. The framework covers quantum field theories on generic Lorentzian manifolds including also pertu ... More
Presented by Klaus FREDENHAGEN on 30 Sep 2016 at 9:00 AM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Recently, Wilson loops in strongly coupled AdS/CFT were found to be invariant under a curious one-parameter family of deformations. In this talk we analyze the nonlocal symmetry underlying this observation. We show that it acts as a raising operator on the Yangian charges and generates the spectral parameter of the model. We also speculate about the possibility to extend this symmetry beyond the s ... More
Presented by Dr. Florian LOEBBERT on 29 Sep 2016 at 3:10 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
We revisit the compatibility between chaotic inflation, which provides a natural solution to the initial condition problem, and the metastable electroweak vacuum, which is suggested by the results of the LHC and the current mass measurements of top quark and Higgs boson. It is known that chaotic inflation poses a threat to the stability of the electroweak vacuum because it easily generates large H ... More
Presented by Dr. Kyohei MUKAIDA on 29 Sep 2016 at 2:30 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Axion monodromy is a promising proposal to achieve a transplanckian field range for an axion in string theory. These models are better described in terms of a Minkowski 3-form field which couples linearly to the axion, in the Kaloper-Sorbo fashion. We highlight the differences between this simple effective theory and the structure actually obtained from string theory. We show that all the RR and N ... More
Presented by Dr. Irene VALENZUELA on 28 Sep 2016 at 4:15 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
The observation of line-like signals of high-energy gamma rays is considered a discovery channel of dark matter. Nevertheless, calculating the rate and the spectral shape associated to these processes is highly non-trivial and depends on the details of the underlying dark matter model. I will argue that, in spite of this situation, there are a number of model-independent statements that can be ... More
Presented by Dr. Camilo Alfredo GARCIA CELY on 28 Sep 2016 at 2:45 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
We give further evidence that genus-one fibers with multi-sections are mirror dual to fibers with Mordell-Weil torsion. In the physics of F-theory compactifications this implies a relation between models with a non-simply connected gauge group and those with discrete symmetries. We explicitly check this observation for torus fibers in two and three dimensional ambient spaces whereas the duality ad ... More
Presented by Paul-Konstantin OEHLMANN on 28 Sep 2016 at 3:35 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Simple single component WIMP Dark Matter (DM) models are under pressure from direct detection (DD). This is related to the relation between annihilation- and DD cross-section in such models. By contrast, multicomponent WIMP DM models leave open a large part of the parameter space and allow for a very rich phenomenology. We study these issues using the example of a UV complete framework containing ... More
Presented by Dr. Christian GROSS on 28 Sep 2016 at 3:30 PM
Session: Plenary Session
Considerable progress has been made in the last few years on various N=2 supersymmetric field theories. The progress includes exact results for expectation values of Wilson loop observables and various other quantities. In my talk I will review some of these developments, and try to extract some lessons of general interest for a wider audience with interests in quantum field theory.
Presented by Joerg TESCHNER on 27 Sep 2016 at 5:20 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
I will describe a class of four dimensional field theories constructed by quotienting ordinary N=4 U(N) SYM by particular combinations of R-symmetry and SL(2,Z) automorphisms. These theories appear naturally on the worldvolume of D3 branes probing terminal singularities in F-theory, where they can be thought of as non-perturbative generalizations of the O3 plane. I will focus on cases preserving o ... More
Presented by Dr. Diego REGALADO on 28 Sep 2016 at 4:55 PM
Session: Parallel Session: Particle Phenomenology - Top Physics
Track: Particle Phenomenology
Presented by Jonas LINDERT on 29 Sep 2016 at 4:45 PM
Session: Plenary Session
Perturbation theory for lattice regularization of field theory is known to be a quite hard subject and this holds true in particular for lattice gauge theory. In the 90's the numerical implementation of stochastic perturbation theory (NSPT) was introduced. NSPT can not only make perturbative computations on the lattice (in some cases much) easier, but also enable the computation of extremely ... More
Presented by Francesco DI RENZO on 27 Sep 2016 at 3:30 PM
Session: Parallel Session: Particle Phenomenology - Top Physics
Track: Particle Phenomenology
Presented by Susanne WESTHOFF on 29 Sep 2016 at 5:05 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
It has been shown that heavy neutral leptons (HNLs) can explain many phenomena seen in Nature such as the neutrino oscillation data, dark matter and the baryon asymmetry. Therefore, alot of theoretical and experimental effort has been put into this subject. I will discuss the parameter space reach of future experiments searching for HNLs at the GeV scale in terms of neutrino mass models with three ... More
Presented by Mr. Rasmus RASMUSSEN on 28 Sep 2016 at 5:00 PM
Session: Parallel Session: Particle Phenomenology - Top Physics
Track: Particle Phenomenology
Presented by Markus SCHULZE on 29 Sep 2016 at 4:05 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
New relations between wall crossing invariants, such as the BPS monodromy, and various limits of superconformal indices of 4d N=2 theories have been recently proposed. For theories of class S on their Coulomb branches, spectral networks provide a way to compute BPS monodromies directly, in a neighborhood of the superconformal point. Several new results on BPS monodromies can be obtained in this w ... More
Presented by Mr. Pietro LONGHI on 28 Sep 2016 at 4:35 PM
Session: Parallel Session: Particle Phenomenology - QCD
Track: Particle Phenomenology
We review Fuchsia: an open-source tool for constructing epsilon form of differential equations for Feynman master integrals based on the Lee algorithm. We show several examples of its application to various problems in Quantum Field Theory which require virtual and real momenta integration. We discuss current status of the project and possible extensions in the future.
Presented by Oleksandr GITULIAR on 28 Sep 2016 at 5:35 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
Presented by Emanuele A. BAGNASCHI on 29 Sep 2016 at 3:20 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Presented by Nezhla AGHAEI on 28 Sep 2016 at 5:30 PM
Session: Plenary Session
Presented by Nima ARKANI-HAMED on 29 Sep 2016 at 11:30 AM
Session: Plenary Session
Besides lattice QCD in particle physics, strongly coupled gauge theories arise, for example, in the condensed matter physics of spin liquids, or in the quantum information theory of Kitaev's toric code, which is a Z(2) lattice gauge theory. Numerical simulations of gauge theories on classical computers, in particular, at high fermion density or in out-of-equilibrium situations, suffer from sever ... More
Presented by Uwe-Jens WIESE on 28 Sep 2016 at 11:40 AM
Session: Plenary Session
I will review the gauge theoretical construction of quantum algebras such as q-deformed W-algebras and quantum groups from the geometry of the moduli space of quiver instantons, moduli space of monopoles and moduli space of vacua of N=2 supersymmetric gauge theories.
Presented by Vasily PESTUN on 28 Sep 2016 at 9:10 AM
Session: Plenary Session
Presented by Thomas DUMITRESCU on 30 Sep 2016 at 11:30 AM
Session: Parallel Session: Particle Phenomenology 1b - BSM
Track: Particle Phenomenology
Relaxion models are an interesting new avenue to explain the radiative stability of the Standard Model scalar sector. They require very large field excursions, which are difficult to generate in a consistent UV completion and to reconcile with the compact field space of the relaxion. We propose an N-site model which naturally generates the large decay constant needed to address these issues. Our m ... More
Presented by Nayara FONSECA on 28 Sep 2016 at 3:20 PM
Session: Parallel Session: Particle Phenomenology - QCD
Track: Particle Phenomenology
Presented by Maria Vittoria GARZELLI on 28 Sep 2016 at 4:55 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
In recent years there has been an increasing interest in computations of the dark matter thermal relic density beyond the leading order in perturbation theory. In this talk we point out that the standard calculation, based on solving the Boltzmann equations, at NLO suffers from a temperature-dependent IR divergence. In an example model we show how both soft and collinear temperature-dependent dive ... More
Presented by Dr. Andrzej HRYCZUK on 28 Sep 2016 at 3:00 PM
Session: Plenary Session
It has been claimed that the super Hubble modes generated during inflation can make loop corrections diverge. Even if we introduce an infrared (IR) cutoff at a comoving scale as an ad hoc but a practical way for the regularization, we encounter the secular growth, which may lead to the breakdown of perturbative expansion for a　sufficiently long lasting inflation. We show that the IR pathology ... More
Presented by Takahiro TANAKA on 30 Sep 2016 at 12:10 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
We investigate nonperturbative renormalization group flows of various Higgs-Yukawa models mimicking the Higgs sector of the standard model. We reanalyze the conventional arguments that relate a lower bound for the Higgs mass with vacuum stability in the framework of the functional renormalization group as well as in the light of exact results for the regularized fermion determinant. In both cases ... More
Presented by René SONDENHEIMER on 29 Sep 2016 at 2:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Standard folk-theorem arguments claim that global charges, such as baryon number, cannot be conserved by semiclassical black holes. We argue that the existence of black holes with classical skyrmion hair invalidates these standard arguments. By carefully analyzing the standard arguments based on a Gedankenexperiment in which a black hole is seemingly-unable to return the baryon number that ... More
Presented by Mr. Alexander GUSSMANN on 29 Sep 2016 at 4:35 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
I'll talk about my work with J. Distler (to appear) in which we study a class of 3d N=4 superconformal field theories and their mass deformations. We perform this study by establishing a relation between the geometry of the vacuum moduli spaces of these theories and (a refined version of) the Theory of sheets" which is an important subject in Geometric Representation Theory. This realizes in a ... More
Presented by Dr. Aswin BALASUBRAMANIAN on 28 Sep 2016 at 5:15 PM
Session: Parallel Session: Particle Phenomenology - QCD & BSM
Track: Particle Phenomenology
Presented by Suvi-Leena LEHTINEN on 29 Sep 2016 at 3:20 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
I will describe how the geometrical properties of the target manifold affect the inflationary predictions of two-field scalar-tensor theories invariant under dilatations. The results presented extend the predictions of the Higgs-dilaton model to a full class of theories defined by an underlying principle. In particular, I will show that when the field-derivative space in the Einstein frame is max ... More
Presented by Dr. Javier RUBIO on 29 Sep 2016 at 4:05 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Rényi entropies, and entanglement entropy in particular, are popular measures of entanglement in quantum theories. We present a holographic method for computing the response of Rényi entropies in conformal field theories to small shape deformations around a flat (or spherical) entangling surface. Our strategy is based on general properties of conformal field theories in the presence of defe ... More
Presented by Marco MEINERI on 29 Sep 2016 at 3:30 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
I discuss the combined resummation of soft and Coulomb-gluon effects for the production of heavy coloured particles at NNLL accuracy, which includes contributions from spin-dependent non-relativistic potentials and so-called annihilation corrections. I present results for squark and gluino pair production at the LHC.
Presented by Dr. Christian SCHWINN on 29 Sep 2016 at 2:40 PM
Session: Parallel Session: Particle Phenomenology 1b - BSM
Track: Particle Phenomenology
The coannihilation mechanism plays a crucial role in determining the DM relic abundance in a plethora of new physics models. Recently, a general classification of simplified models for this mechanism has been presented in the Coannihilation codex. In particular, the thermal relic abundance of a pure Standard Model singlet DM candidate can naturally be explained by coannihilation with a new colored ... More
Presented by Dr. Maikel DE VRIES on 28 Sep 2016 at 2:00 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Three-point functions of generic gauge invariant composite operators in N=4 SYM are very hard to construct in higher-order weak-coupling perturbation theory. On the other hand, three-point functions of half-BPS operators are non-renormalised, and guided by symmetry principles the integrands for their four-point functions can be constructed to high loop order at least in the planar theory. We sketc ... More
Presented by Burkhard EDEN on 28 Sep 2016 at 3:00 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
Minimal chaotic models of D-term inflation predicts too large primordial tensor perturbations. Although it can be made consistent with observations utilizing higher order terms in the Kaehler potential, expansion is not controlled in the absence of symmetries. We comprehensively study the conditions of Kaehler potential for D-term plateau-type potentials and discuss its symmetry. They include the ... More
Presented by Ken'ichi SAIKAWA on 29 Sep 2016 at 4:50 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
Presented by Simone LIONETTI on 28 Sep 2016 at 2:40 PM
Session: Plenary Session
The term Tensor Network States (TNS) has become a common one in the context of numerical studies of quantum many-body problems. It refers to a number of families that represent different ansatzes for the efficient description of the state of a quantum many-body system. The first of these families, Matrix Product States (MPS), lies at the basis of Density Matrix Renormalization Group methods, which ... More
Presented by Mari Carmen BANULS on 29 Sep 2016 at 12:10 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
We determine constraints on sterile neutrino warm dark matter through direct detection experiments, taking XENON100, XENON1T and DARWIN as example. While not competitive with astrophysical constraints from X-ray data, the constraints are the first direct laboratory bounds on sterile neutrino warm dark matter, and will be in some parts of parameter space the strongest limits on keV-scale neutrinos.
Presented by Mr. Miguel CAMPOS on 28 Sep 2016 at 5:15 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
We present a non-perturbative study of a five-dimensional Gauge-Higgs Unification model on the lattice using Monte Carlo simulations. We find a region in the Higgs phase where the ratio of the Higgs to the gauge boson mass is like in the Standard Model. In the same region we observe localization to four dimensions. Despite the non existence of a second order phase transition, cut-off effects are ... More
Presented by Francesco KNECHTLI on 28 Sep 2016 at 3:00 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
Presented by Pedro LIENDO on 29 Sep 2016 at 4:05 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
We investigate the formation of a dark matter halo using an idea that is rooted in the correspondence between phase space distributions in classical and quantum mechanics. The dynamics of cold dark matter is governed by the Vlasov (or collisionless Boltzmann) equation whose nonlinearity is induced by gravity according to the Poisson equation. Determining the evolution of density and velocity dema ... More
Presented by Dr. Cora UHLEMANN on 29 Sep 2016 at 3:00 PM
Session: Plenary Session
The Yang-Mills gradient flow provides new insight into the dynamics of non-Abelian gauge theories and has become a widely used tool in lattice QCD. In this talk, the theoretical foundation of the flow is reviewed and some of its applications are briefly described.
Presented by Martin LUESCHER on 27 Sep 2016 at 2:50 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
In the sense of perturbation theory around arbitrary classical solutions, the Nambu-Goto (NG) string can be consistently quantised as an effective theory for any dimension $D$ of the target space [Comm. Math. Phys. 327 (2014) 779, with D. Bahns & K. Rejzner]. In this framework, we compute semi-classical corrections to the energy of rotating NG strings, using the locally covariant renormalisation s ... More
Presented by Jochen ZAHN on 28 Sep 2016 at 2:40 PM
Session: Parallel Session: Particle Phenomenology - QCD
Track: Particle Phenomenology
I will present the ALPHA collaboration's latest calculation of the Lambda parameter of QCD. Our method relies on experimental inputs of low energy quantities like pseudo-scalar decay constants only. The scale dependence of a coupling in a finite volume renormalization scheme is computed non-perturbatively in lattice QCD over many orders of magnitude in the energy scale. At high energies pe ... More
Presented by Dr. Tomasz KORZEC on 28 Sep 2016 at 5:15 PM
Session: Parallel Session: Particle Phenomenology - QCD
Track: Particle Phenomenology
In my talk I introduce the ColorFulNNLO method to calculate NNLO QCD corrections to any IR-safe observable in the case of three-jet production in electron-positron annihilation. Provided the ColorFulNNLO method is general it was implemented in a computer code called MCCSM (Monte Carlo for the ColorFulNNLO Subtraction Method). The capabilities of the code are demonstrated by calculating standa ... More
Presented by Dr. Adam KARDOS on 28 Sep 2016 at 4:15 PM
Session: Parallel Session: Particle Phenomenology - Top Physics
Track: Particle Phenomenology
Top quark physics is entering a precision era with the LHC Run II. A comprehensive study of top quark pair production in association with one hard jet in the di-lepton decay channel is presented for a center-of-mass energy of 13 TeV. The NLO QCD calculation takes into account all resonant and non-resonant and interference contributions for off-shell top quarks, and W and Z bosons. Theoretical unce ... More
Presented by Mr. Manfred KRAUS on 29 Sep 2016 at 4:25 PM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
The discovery of a Higgs-like particle at the LHC has triggered considerable ongoing effort to reveal its nature and properties. The mass of the particle is one of its basic properties; due to the high-precision mass measurement, higher-order calculations are necessary to make competitive predictions. Although with current experimental results the particle could be identified as the Standard Model ... More
Presented by Dr. Sebastian PAßEHR on 29 Sep 2016 at 2:20 PM
Session: Parallel Session: Particle Phenomenology - QCD & BSM
Track: Particle Phenomenology
We present the evaluation of the two-loop ${\cal O}(m_e^2/s)$ contribution to the wide-angle high-energy electron-positron scattering in the double-logarithmic approximation. The origin and the general structure of the power-suppressed double logarithmic corrections are discussed.
Presented by Dr. Nikolai ZERF on 29 Sep 2016 at 2:40 PM
Session: Plenary Session
We start by reviewing UV completion of the Gross-Neveu model in dimensions between two and four via the Gross-Neveu-Yukawa model, which is a multi-flavor Yukawa theory. We discuss the operator scaling dimensions and the sphere free energy for these Conformal Field Theories. The case of a single two-component Majorana fermion is special in that the theory appears to flow to a CFT with emergent su ... More
Presented by Igor KLEBANOV on 27 Sep 2016 at 2:10 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
I will describe a minimal extension of the Standard Model of particle physics that accounts for inflation, dark matter, baryogenesis, the smallness of neutrino masses and solves the strong CP problem, with a new physics scale around ~10^11 GeV.
Presented by Guillermo BALLESTEROS on 29 Sep 2016 at 2:00 PM
Session: Plenary Session
Presented by Luis Fernando ALDAY on 30 Sep 2016 at 10:20 AM
Session: Parallel Session: Particle Phenomenology 1a - Higgs & BSM
Track: Particle Phenomenology
We will report on the recent calculation of the NLO QCD corrections to vector boson pair production in gluon fusion, focussing in particular on its interference with the Higgs signal. In particular, as it was shown by Caola and Melnikov, assessing the impact of the interference on the signal and background cross sections in the high energy tail (i.e. for an off-shell Higgs) is crucial to put strin ... More
Presented by Lorenzo TANCREDI on 28 Sep 2016 at 2:20 PM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
In the context of constructing interacting quantum field theories in the operator-algebraic approach, wedge-local fields play an important role. After the work of Lechner to construct factorizing scattering matrix models with scalar S-matrices without bound states, we recently extended this construction to the Z(N)-Ising model and the A_N-1 affine Toda field theories, namely models with a richer p ... More
Presented by Dr. Daniela CADAMURO on 29 Sep 2016 at 4:25 PM
Presented by Joachim MNICH on 28 Sep 2016 at 9:00 AM
Session: Welcome
Presented by Gleb ARUTYUNOV on 27 Sep 2016 at 2:00 PM
Session: Plenary Session
The last years have seen remarkable progress in understanding the scattering amplitudes of massless particles in arbitrary dimension. They not only exhibit a simplicity completely obscured by the Feynman Diagram approach, but also a structure strikingly reminiscent of the worldsheet models describing string theory. After reviewing the key developments, I will discuss the worldsheet models, derive ... More
Presented by Yvonne GEYER on 29 Sep 2016 at 10:20 AM
Session: Parallel Session: Strings & Mathematical Physics
Track: String & Mathematical Physics
In this talk we derive the tree-level S-matrix of the effective theory of Goldstone bosons known as the non-linear sigma model (NLSM) from string theory. This novel connection relies on a recent realization of tree-level open-superstring S-matrix predictions as a double copy of super-Yang--Mills theory with Z-theory --- the collection of putative scalar effective field theories encoding al ... More
Presented by Dr. Oliver SCHLOTTERER on 29 Sep 2016 at 2:30 PM
Session: Parallel Session: Cosmology & Astroparticle Physics
Track: Cosmology & Astroparticle Physics
In the absence of a clear WIMP signal, we should think about alternative candidates for Dark Matter. A very well motivated example is a (up to now hypothetical) sterile neutrino with a mass of a few keV. In this talk, I will give an overview over the topic of keV sterile neutrino Dark Matter, with a particular focus on Dark Matter production in the early Universe and on phenomenological considerat ... More
Presented by Dr. Alexander MERLE on 28 Sep 2016 at 2:00 PM