Francesca Calore
26/09/2017, 15:30
Will Percival
26/09/2017, 16:40
David Kaplan
(U. Johns Hopkins)
27/09/2017, 09:50
Angnis Schmidt-May
(LMU Munich)
27/09/2017, 12:20
Mr
Andreas Rappelt
(Technische Universität München)
27/09/2017, 14:00
Cosmology & Astroparticle Physics
Recent results from N-body simulations point towards the existence of non-virialized structures in the dark matter halo. This weakens the assumptions of the Standard Halo Model and increases the need for ways to analyze results of direct dark matter searches without specifying a halo model. We propose a numerical method that compares an arbitrary number of results from direct detection...
Miguel Montero
(Utrecht)
27/09/2017, 14:00
String & Mathematical Physics
Consistency with quantum gravity and black hole physics puts
significant constraints on low-energy effective field theories. In fact,
most EFT’s do not satisfy these criteria, and are said to be in the
“Swampland”. Most Swampland constraints remain conjectural, supported
mainly by a plethora of stringy examples. In this talk I will discuss a
rigorous example of a Swampland...
Anders Kvellestad
(Nordita)
27/09/2017, 14:00
Particle Phenomenology
I will give a brief introduction to the public software package GAMBIT (the Global and Modular Beyond-the-Standard-Model Inference Tool) and present the first SUSY results from the BSM science programme currently being pursued with it. We have performed global fit analyses of both GUT-scale and weak-scale parameterisations of the MSSM. Our analyses improve on existing results in terms of the...
Mrs
Maria Archidiacono
(RWTH Aachen)
27/09/2017, 14:00
Cosmology & Astroparticle Physics
The motivation for new non-standard interactions in the sterile neutrino sector arises from the tension between oscillation experiments and cosmological results. Indeed the former point towards the existence of one (or more) sterile neutrino in the eV mass range, while the latter disfavor additional thermalized light particles with high statistical significance. However a partial...
Dr
Sebastian Wild
(DESY)
27/09/2017, 14:17
Cosmology & Astroparticle Physics
One of the simplest particle physics realizations of self-interacting dark matter is a WIMP interacting with a MeV-scale scalar mediator. While this scenario is already largely excluded for dark matter masses above ~5 GeV by null searches from various direct detection experiments, future low-threshold detectors such as CRESST and CDMS could be sensitive to so far unexplored regions of the...
Dr
Alexander Voigt
(RWTH Aachen)
27/09/2017, 14:17
Particle Phenomenology
In several supersymmetric (SUSY) models the Higgs mass is predicted to be smaller than the Z boson mass. Therefore, in order for a SUSY model to predict the correct Higgs mass of 125 GeV, large loop corrections are required. Such large loop corrections are achieved in scenarios with large stop masses and/or a large stop mixing. However, the large loop corrections lead to a slow convergence...
Dr
Stefan Vogl
(Max-Planck-Institut für Kernphysik)
27/09/2017, 14:17
Cosmology & Astroparticle Physics
Sterile neutrinos produced through resonant or non-resonant oscillations are a well motivated dark matter candidate, but recent constraints from observations have ruled out most of the parameter space. Based on general considerations we find a thermalization mechanism which can increase the yield after resonant and non-resonant production. At the same time, it alleviates the growing tensions...
Ms
Irene Valenzuela
(Utrecht University)
27/09/2017, 14:20
String & Mathematical Physics
It is known that there are AdS vacua obtained from compactifying the Standard Model to 2 or 3 dimensions. However, using the Weak Gravity Conjecture, it has been recently argued by Ooguri and Vafa that non supersymmetric stable AdS vacua are incompatible with quantum gravity. By requiring the absence of these vacua we can put constraints on the SM spectra, obtaining a lower bound for the...
Dr
Cedric Weiland
(IPPP Durham University)
27/09/2017, 14:34
Particle Phenomenology
Massive neutrinos are required to explain the observation of neutrino oscillations. One of the simplest extension of the Standard Model that can successfully generate neutrino masses and mixing is the addition of fermionic gauge singlets or heavy sterile neutrinos. If an approximate lepton number symmetry is present, these sterile neutrinos can have a mass close to the TeV-scale with large...
Mr
Aaron Vincent
(Imperial College London)
27/09/2017, 14:34
Cosmology & Astroparticle Physics
The O(1) relationship between the standard model and dark matter relic abundances suggests a connection that is more than just gravitational. If the main portal between the dark and visible sectors is not via charged particles, but rather via neutrinos, then both cosmological phenomenology and search methods here on Earth must be modified. I will discuss the impact of DM-neutrino interactions...
Mr
Tobias Binder
(ITP, Goettingen University)
27/09/2017, 14:34
Cosmology & Astroparticle Physics
The understanding of theoretical uncertainties in the production mechanism of dark matter (DM) particles in the Early Universe has become an important topic from the viewpoint of the percent-level accuracy in the observational determination of the relic abundance. We consider the case where heavy DM self-interacts via t-channel exchange of a light gauge boson, leading to a Sommerfeld-enhanced...
Timm Wrase
(Vienna)
27/09/2017, 14:40
String & Mathematical Physics
I will discuss how a better understanding of non-linearly realized supergravity has led to interesting progress and an improved understanding of dS vacua and inflation in supergravity and string flux compactifications.
Mr
Thejs Brinckmann
(RWTH Aachen)
27/09/2017, 14:51
Cosmology & Astroparticle Physics
Cosmological experiments are exceptionally sensitive to the sum of neutrino masses. Future surveys have the potential to provide a precise measurement of the total neutrino mass, or to establish the neutrino hierarchy. To reliably estimate this, it is crucial to properly account for parameter degeneracies, i.e. how measurements improve or deteriorate with different physical models, such as...
Dr
Michael Gustafsson
(Göttingen University)
27/09/2017, 14:51
Cosmology & Astroparticle Physics
Today’s standard formalism to calculate the abundance of thermally produced dark matter particles relies on the underlying assumption that annihilating dark matter particles are in kinetic equilibrium throughout the freeze-out period. I will point out that this assumption does not have to be fulfilled in general and then present two methods on how to generalize the formalism in order to deal...
Jonas Wittbrodt
(DESY)
27/09/2017, 14:51
Particle Phenomenology
The complex two-Higgs doublet model is one of the simplest ways to extend the scalar sector of the Standard Model to include a new source of CP-violation. This can address the matter antimatter asymmetry in the universe through electroweak baryogenesis and can also lead to interesting collider phenomenology.
Quantifying the amount of CP-violation, however, remains a surprisingly non-trivial...
Dr
Marco Scalisi
(KU Leuven)
27/09/2017, 15:00
String & Mathematical Physics
We develop a new class of supergravity cosmological models where inflation is induced by terms in the Kähler potential which mix a nilpotent superfield S with a chiral sector Φ. As the new terms are non-(anti)holomorphic, and hence cannot be removed by a Kähler transformation, these models are intrinsically Kähler potential driven. Such terms could arise for example due to a backreaction of an...
Mr
Thibaud Vantalon
(IFAE/DESY)
27/09/2017, 15:08
Particle Phenomenology
The Higgs self-coupling is notoriously intangible at the LHC. It was recently proposed to probe the trilinear Higgs interaction through its radiative corrections to single-Higgs processes. This approach however requires to disentangle these effects from those associated to deviations of other Higgs-couplings to fermions and gauge bosons. We show that a global fit exploiting only single-Higgs...
Ms
Isabel M. Oldengott
(Universität Bielefeld)
27/09/2017, 15:08
Cosmology & Astroparticle Physics
The lepton asymmetry of the Universe is one of the most weakly constrained cosmological parameters. Whereas the
baryon asymmetry is tightly constrained to be at the order $\mathcal{O}(10^{-9})$, the lepton asymmetry could be larger by
many orders of magnitude.
A cosmic lepton asymmetry affects the primordial helium
abundance and the expansion rate of the early Universe. Both of these...
Ayuki Kamada
(IBS-CTPU)
27/09/2017, 15:08
Cosmology & Astroparticle Physics
Kinetic interaction (e.g., elastic scatterings) between dark matter particles and those in the thermal bath does not change the dark matter number, but it may affect the relic density of dark matter.
In particular it plays an essential role in determining the relic abundance of strongly interacting massive particles, which may solve issues in the (sub-)galactic structure formation of the...
Mr
Jakob Moritz
(DESY)
27/09/2017, 15:20
String & Mathematical Physics
Using a 10D lift of non-perturbative volume stabilization in type IIB string theory we find that the simplest KKLT vacua cannot be uplifted to de Sitter upon inclusion of SUSY breaking sources like anti-branes. Rather, the uplift is flattened due to stronger back-reaction on the volume modulus than has previously been anticipated such that the resulting vacua are always AdS. We find that this...
Dr
Alfredo Urbano
(CERN)
27/09/2017, 15:25
Cosmology & Astroparticle Physics
It is commonly believed that no global symmetries can exist in a consistent theory of quantum gravity.
This "folk argument" can be put on more solid and quantitative ground by explicitly constructing non-perturbative gravitational instanton solutions.
In this talk, I will review such solutions in the case of an axion field minimally coupled to Einstein gravity. I will discuss both...
Sebastian Ingenhütt
(TU of Munich and MPP, Munich)
27/09/2017, 15:26
Cosmology & Astroparticle Physics
One of the key properties of dark matter particles is their longevity. However, even if dark matter is absolutely stable against decay in flat spacetime, as commonly assumed in the literature, the presence of nonminimal couplings to gravity of the dark matter field can spoil this stability in curved spacetime, with potentially remarkable phenomenological implications. More specifically, a...
Dr
Alessandro Cuoco
(RWTH Aachen TTK)
27/09/2017, 16:05
Cosmology & Astroparticle Physics
I will discuss the implication for dark matter (DM) indirect searches of the recent precise measurements of cosmic-ray (CR) antiprotons from AMS-02 .
With respect to previous works we use a new updated CR propagation model
consistent with the AMS-02 data.
Furthermore, we fit at the same time, in a self-consistent way,
both DM and the propagation parameters.
We find a significant...
Stijn van Tongeren
(HU Berlin)
27/09/2017, 16:05
String & Mathematical Physics
Strings moving in symmetric spaces are integrable models and can be ``solved'' exactly. Such strings play an important role in furthering our understanding of the AdS/CFT correspondence. In recent years many further integrable string theories were discovered, based on deformations of symmetric space strings. I will give an overview of these integrable models, their interpretation in terms of...
Mr
Darren Scott
(IPPP Durham)
27/09/2017, 16:05
Particle Phenomenology
Top quark physics has now entered the precision era with billions of top pairs expected to be produced over the lifetime of the LHC. As such, the need for ever more accurate theory predictions continues to grow. Using a formalism derived from Soft Collienar Effective Theory (SCET), we present predictions for differential cross sections which incorporate the simultaneous resummation of soft and...
Mr
Juraj Klarić
(Technical University Munich)
27/09/2017, 16:05
Cosmology & Astroparticle Physics
Heavy neutrinos with masses below the electroweak scale can simultaneously generate the light neutrino masses via the seesaw mechanism and the baryon asymmetry of the universe via leptogenesis. The requirement to explain these phenomena imposes constraints on the mass spectrum of the heavy neutrinos, their flavour mixing pattern and their CP properties. We first combine bounds from different...
Dr
Ye-Ling Zhou
(IPPP Durham)
27/09/2017, 16:22
Cosmology & Astroparticle Physics
The simplest description of Majorana neutrino masses is the dimension-5 lepton-number-violating Weinberg operator. It automatically provides out-of-equilibrium dynamics in the early Universe due to the suppression of neutrino masses. Three Sakharov conditions are satisfied if there is a CP-violating phase transition. The latter is strongly motivated by the breaking of some underlying...
Nathan Hartland
(NIKHEF)
27/09/2017, 16:22
Particle Phenomenology
The latest update in the NNPDF series of PDF determinations, NNPDF3.1, includes
a great deal of new experimental information on proton structure determined by collaborations at the LHC and Tevatron. Several of these new datasets provide particular challenges to PDF fitters due to their high-precision nature. We shall discuss the impact upon PDF fits of these new measurements, including W and...
Dr
Martin Winkler
(Nordita Stockholm)
27/09/2017, 16:22
Cosmology & Astroparticle Physics
I discuss the indirect search for dark matter in the light of the lastest AMS-02 results.
Rob Klabbers
(Univ. of Hamburg)
27/09/2017, 16:25
String & Mathematical Physics
I will report on the construction of the Quantum Spectral Curve (QSC) for the eta-deformation of the AdS_5 x S^5 superstring. The Quantum Spectral Curve is a very simple set of equations and boundary conditions that describe the spectrum of the deformed string theory. It can be regarded as a trigonometrisation of the QSC that formed the ultimate simplification of the spectral problem of the...
Marc Montull
(DESY)
27/09/2017, 16:39
Particle Phenomenology
Diboson production at the LHC is already setting competitive bounds on anomalous triple gauge couplings (aTGC) for certain types of theories due to the increase in energy. Within the SMEFT, the leading contributions at high energy to this process depend on a combination of aTGC plus other operators. Until now the contribution of these other operators was negligible due to being very...
Koji Ishiwata
(Kanazawa University)
27/09/2017, 16:39
Cosmology & Astroparticle Physics
It has been long discussed that cosmic rays may contain signals of dark matter. In the last couple of years an anomaly of cosmic-ray positrons has drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has been reported by AMS-02 collaboration. Both excesses may indicate towards decaying or annihilating dark matter with a mass of around 1–10 TeV. In this article we study...
Ms
Jorinde van de Vis
(Nikhef)
27/09/2017, 16:39
Cosmology & Astroparticle Physics
Effective field theory is an attractive framework to study Electroweak Baryogenesis in a model-independent way. We add a dimension-six operator to the Higgs potential in order to have a strongly first order phase transition, which is necessary for successful baryogenesis. Another necessary ingredient is CP-violation, which can be provided by dimension-six interactions between the Higgs and the...
Reimar Hecht
(ETH Zurich)
27/09/2017, 16:45
String & Mathematical Physics
Beisert's S-matrix was fixed by centrally extended sl(2|2) symmetry. Here we examine q-deformed centrally extended sl(2|2) and its sl(2) automorphisms for which we obtain the Hopf structure and the universal R-matrix. In addition, we consider this algebra as a contraction limit of the exceptional Lie superalgebra d(2,1,\alpha). This is closely related to 3D kappa-Poincaré for which we find a...
Mr
Kai Schmitz
27/09/2017, 16:56
Cosmology & Astroparticle Physics
In models of inflation driven by an axion-like pseudoscalar field, the
inflaton, a, may couple to the standard model hypercharge gauge field
via a Chern-Simons-type interaction, L ⊃ a F F̃. This coupling results
in the explosive production of hypermagnetic fields during inflation,
which has two interesting consequences: (1) The primordial hypermagnetic
field is maximally helical and,...
Dr
Barabanov Mikhail
(JINR)
27/09/2017, 16:56
Particle Phenomenology
The spectroscopy of charmonium-like mesons with masses above the DD\bar threshold has been full of surprises, and their nature remains poorly understood [1]. The currently most compelling theoretical descriptions of the mysterious XYZ mesons attributes them to higher lying charmonium states [2], hybrid structure with a tightly bound diquark [3, 4] or a tetraquark [3, 5] core that strongly...
Dr
Michael Kopp
(Institute of Physics of the Czech Academy of Sciences)
27/09/2017, 16:56
Cosmology & Astroparticle Physics
Dark Matter (DM) is a crucial component of the universe and, for calculations of the cosmic microwave background (CMB), is successfully modelled as a pressureless perfect fluid within General Relativity (GR).
With data from Planck it becomes possible to test generalisations of this model, searching for DM properties beyond the pressureless perfect fluid and thereby testing the CDM paradigm...
Robin Brueser
(Univ. Mainz)
27/09/2017, 17:05
String & Mathematical Physics
We study massive scattering amplitudes in N=4 super-Yang-Mills in the planar limit, where the mass is generated through a Higgs mechanism. The scattering amplitudes we consider are those of massless gauge bosons interacting through loops of massive W bosons. In such a model it is known that at leading power, both the Regge limit, as well as the soft divergences are controlled by the anomalous...
Jacopo Fumagalli
(Nikhef)
27/09/2017, 17:13
Cosmology & Astroparticle Physics
We consider different types of single field inflationary models such as Higgs inflation-types and the attractors models. We discuss their unitarity and renormalizability properties. Once quantum corrections are considered, new physics is demanded. As a matter of fact, to consistently connect the low and high energy regimes of the effective field theories (described in terms of Standard model...
Mr
Sebastian Bruggisser
(DESY Theory-Group)
27/09/2017, 17:13
Cosmology & Astroparticle Physics
Varying Yukawas open new possibilities for electroweak baryogenesis. In this talk I will focus on the CP-violation and the baryon-asymmetry. Starting from first principles, I will derive the general form of the CP-violating semiclassical force and the diffusion equations for models with varying Yukawa couplings. This represents a very general framework to determine the baryon-asymmetry...
Mr
Johannes Knaute
(Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf)
27/09/2017, 17:13
Particle Phenomenology
We study a holographic Einstein-Maxwell-dilaton model, which is adjusted to lattice QCD data for 2+1 flavors and physical quark masses for the equation of state and quark number susceptibility at zero baryo-chemical potential, to explore the resulting phase diagram over the temperature-chemical potential plane. A first-order phase transition sets in at a temperature of about 112 MeV and a...
Dennis Müller
(HU Berlin)
27/09/2017, 17:25
String & Mathematical Physics
We consider an all-loop conformal Yangian symmetry of
four-dimensional fishnet Feynman integrals being built from four-valent
vertices which are connected via scalar massless propagators. We will
discuss the implications of the Yangian symmetry in terms of
differential equations for these graphs and also comment on their
relation to observables in an integrable bi-scalar field theory...
Alan Guth
27/09/2017, 18:00
Julien Lesgourgues
28/09/2017, 09:50
Raphael Flauger
28/09/2017, 10:30
Dr
Marco Drewes
(Université catholique de Louvain)
28/09/2017, 14:00
Cosmology & Astroparticle Physics
We show that the parameter space of single field models of inflation contains viable regions in which the inflaton couplings to radiation can be determined from the properties of CMB temperature fluctuations, in particular the spectral index. This may be the only way to measure these fundamental microphysical parameters, which shaped the universe by setting the initial temperature of the hot...
Dr
Juri Smirnov
(INFN Firenze)
28/09/2017, 14:00
Cosmology & Astroparticle Physics
I will discuss the importance of bound-state formation in the dark matter sector.
On the one hand as we have shown in a recent publication, the effect of unstable bound states is crucial for the correct computation of WIMP relic abundances. On the other hand capture photon detection from late time bound state formation will provide a new search method for heavy, multi-TeV dark matter. I will...
Jean - Luc Lehners
(AEI Golm)
28/09/2017, 14:00
String & Mathematical Physics
I will discuss a fundamental obstruction to any theory of the beginning of the universe, formulated as a semiclassical path integral. Hartle and Hawking’s no boundary proposal and Vilenkin’s tunneling proposal are examples of such theories. Each may be formulated as the quantum amplitude for obtaining a final 3-geometry by integrating over 4-geometries. The result is obtained using a new...
Dr
Juan Herrero Garcia
(University of Adelaide, CoEPP)
28/09/2017, 14:00
Particle Phenomenology
Given the stringent upper limits from direct detection experiments, one possibility is that dark matter scatters with nuclei only at the loop level. In the first part of the talk, I will discuss direct detection signals of simplified models. We impose current limits and analyse how next generation experiments can constrain the dark matter parameter space. In the second part, I analyse the case...
Dr
Felix Kahlhoefer
(DESY)
28/09/2017, 14:17
Particle Phenomenology
Light pseudoscalars interacting dominantly with Standard Model
gauge bosons (so-called axion-like particles or ALPs) occur frequently in extensions of the Standard Model. There is consequently a great interest in searches for ALPs both at the energy frontier and at the intensity frontier. In my talk I will review these different strategies and present an overview of existing constraints. I...
Mr
Maximilian Ruhdorfer
(Technische Universität München)
28/09/2017, 14:17
Cosmology & Astroparticle Physics
We consider a composite model where both the Higgs and a complex scalar χ, which is the Dark Matter (DM) candidate, arise as light pseudo Nambu-Goldstone bosons (pNGBs) from a strongly coupled sector with TeV scale confinement. The global symmetry structure is SO(7)/SO(6), and
the DM is charged under an exact U(1) DM ⊂ SO(6) that ensures its stability. Depending on whether the χ shift...
Dr
Jonathan Frazer
(DESY)
28/09/2017, 14:17
Cosmology & Astroparticle Physics
Incorporating stochastic methods into the model building process can significantly improve our understanding of how to reliably compute predictions. In addition, as high energy physics models of inflation continue to improve, it is expected that they will become increasingly complex. This again makes the use of stochastic methods an appealing option, as they present a wealth of new tools for...
Sebastian Bramberger
(MPI-AEI Golm)
28/09/2017, 14:20
String & Mathematical Physics
We study quantum mechanical tunneling using complex solutions of the classical field equations. Simple visualization techniques allow us to unify and generalize previous treatments, and straightforwardly show the connection to the standard approach using Euclidean instanton solutions. Applying these techniques to quantum cosmology we describe transitions between classical patches of the...
Alexis Plascencia
(Durham University, IPPP)
28/09/2017, 14:34
Particle Phenomenology
We introduce a new set of simplified models to address the effects of 3-point interactions between the dark matter particle, its dark co-annihilation partner, and the Standard Model degree of freedom, which we take to be the tau lepton. We investigate these effects as well as the discovery potential for dark matter co-annihilation partners at the LHC. A small mass splitting between the dark...
Clarissa Siqueira
(Max Planck Institut für Kernphysik)
28/09/2017, 14:34
Cosmology & Astroparticle Physics
Secluded dark matter models feature dark matter annihilations into a metastable mediator which then decays into Standard Model fermions. In this work, we test these models using current data from the Fermi-LAT (6-year observation of dwarf spheroidal galaxies) and the H.E.S.S.~(10-year observation of the Galactic center) instrument. Assuming that the metastable mediator shortly decays into...
Mafalda Dias
(DESY)
28/09/2017, 14:34
Cosmology & Astroparticle Physics
An ultraviolet-complete description of inflation may not be simple. Indeed, our best paradigm for physics at high energies seems to point towards a low-energy effective potentials with a large number of degrees of freedom. Cosmological data however shows a very simple primordial distribution of matter. I will discuss how complex inflation can give rise to universal simple predictions by...
Martin Ammon
(Univ. of Jena)
28/09/2017, 14:40
String & Mathematical Physics
It is still an open question how general holographic dualities are, and what they possibly tell us about quantum gravity in asymptotically flat spacetimes. In this talk I will focus on a concrete example of an holographic duality involving higher spin gravity. In particular, I report on recent progress within three-dimensional higher spin gravity concerning the flat space limit and the soft...
Thomas Schwetz-Mangold
(KIT)
28/09/2017, 14:51
Cosmology & Astroparticle Physics
If the PQ phase transition happens after inflation, the axion energy density will have density fluctuations of order one. The size of the fluctuations is set by the horizon size at the QCD phase transition. Those fluctuations lead to the formation of gravitationally bound objects called miniclusters. A significant fraction of axion dark matter bound in miniclusters would have severe...
Dr
Mindaugas Karčiauskas
(University of Jyväskylä)
28/09/2017, 14:51
Cosmology & Astroparticle Physics
Currently favoured values of the Standard Model parameters show that the model can be consistently extended all the way up to the Planck scale. The only required new physics at high energies being inflation. However, those values also indicate that at high energies the SM potential might have another, much deeper negative minimum. We show, that apparent negative states do not exclude high...
Satoshi Shirai
(Kavli IPMU)
28/09/2017, 14:51
Particle Phenomenology
The Higgsino is the most promising candidate for the dark matter.
The almost pure Higgsino, however, is known to be a very challenging target at the LHC.
I will show that improvement of tracking technique of disappearing tracks can significantly increase the sensitivity for the Higgsino.
I will also discuss a future 33 TeV collider can probe the 1 TeV Higgsino, which is the most...
Marcus Sperling
(Univ. Vienna)
28/09/2017, 15:00
String & Mathematical Physics
In this talk, I will discuss how the two geometric notions "fan" and
"monoid" can be very fruitful for the understanding of the Coulomb
branch Hilbert series (the monopole formula) for 3d N=4 gauge theories.
After a brief reminder of the monopole formula, I will introduce the
matter fan and reorganise the monopole formula accordingly. I then
discuss the resulting algebraic properties...
Mr
Chao Zhang
(IEXP/Univ.Hamburg)
28/09/2017, 15:08
Cosmology & Astroparticle Physics
In previous works, effective field theories (EFT) have been used to scan the relevant parameter space for single dark sector particle. We have extended upon that work to include co-annihilation as well as Sommerfeld enhancement. To this end, we have calculated solutions to the Boltzmann equation for the case of a more complex dark sector with arbitrary mass spectrum, interactions and particle...
Marco Zatta
(University of Helsinki)
28/09/2017, 15:08
Cosmology & Astroparticle Physics
Current measurements of the Higgs boson and top quark mass favor metastability of the electroweak vacuum in the Standard Model. This raises some questions when we consider the evolution of our universe: how the Higgs ended up in such an energetically disfavored state? Why it remained there during inflation? These problems can be addressed by assuming that the Higgs couples directly to the...
Michael Duerr
(DESY)
28/09/2017, 15:08
Particle Phenomenology
I will discuss a novel signature of dark matter production at the LHC resulting from the emission of an additional Higgs boson in the dark sector. The presence of such a dark Higgs boson is motivated simultaneously by the need to generate the masses of the particles in the dark sector and the possibility to relax constraints from the dark matter relic abundance by opening up a new annihilation...
Cedric Troessaert
(MPI-AEI Golm)
28/09/2017, 15:20
String & Mathematical Physics
A few years ago Strominger argued that the BMS4 algebra, usually
defined at null infinity, should be regarded as a true symmetry of
gravitational evolution of asymptotically flat space-times. This
implies the existence of an infinite tower of conserved quantities
and brings new insight to various problems like gravitational
scattering or black-holes evaporation. In this talk, I will...
Dr
Sofiane Boucenna
(KTH Royal Institute of Technology)
28/09/2017, 15:25
Cosmology & Astroparticle Physics
SO(10) grand unified theories can ensure the stability of new particles in terms of the gauge group structure itself, and in this respect are well suited to motivate and accommodate dark matter (DM) candidates in the form of new stable massive particles. I will give an overview of DM scenarios and related phenomenology within the framework of non-supersymmetric SO(10). In the last part of the...
Mr
Hajime Fukuda
(Kavli IPMU)
28/09/2017, 15:25
Particle Phenomenology
Ultralight bosonic particle is one of the dark matter and called fuzzy dark matter.
Its astrophysical properties are interesting and have been recently studied.
On the other hand, the detection method is less discussed. We propose a new method to detect them using the motions of heavenly bodies.
(This is a work in progress)
Dr
Gaurav Goswami
(Ahmedabad University)
28/09/2017, 15:25
Cosmology & Astroparticle Physics
The success of a given inflationary model crucially depends upon two features: its predictions for observables such as those of the Cosmic Microwave background (CMB) and its insensitivity to the unknown ultraviolet (UV) physics such as quantum gravitational effects. Extranatural inflation is a well motivated scenario which is insensitive to UV physics by construction. In this five dimensional...
Mario Flory
(MPI Munich & Jagellonian Univ.)
28/09/2017, 16:05
String & Mathematical Physics
I use a recently proposed holographic Kondo model as a well-understood example of AdS/boundary CFT (BCFT) duality and show explicitly that in this model the bulk volume decreases along the RG flow. I then obtain a proof that this volume loss is indeed a generic feature of AdS/BCFT models of the type proposed by Takayanagi in 2011. According to recent proposals holographically relating bulk...
Dr
David Straub
(TUM)
28/09/2017, 16:05
Particle Phenomenology
Several deviations from Standard Model expectations have been observed in decays of B mesons in recent years, including hints for violation of lepton flavour universality in b->c and b->s transitions and deviations in branching ratios and angular observables in exclusive semileptonic rare decays. While these "anomalies" could be explained by a combination of statistical fluctuations in some...
Mr
Sebastian Clesse
(RWTH Aachen)
28/09/2017, 16:05
Cosmology & Astroparticle Physics
Since the detection by Advanced LIGO/VIRO of gravitational waves emitted by black holes with masses beyond most expectations, primordial black holes (PBH) have seen a revival of interest as a possible Dark Matter candidate, supported by the coincidence between inferred merging rates by LIGO and the expected rates for PBH abundances comparable to the Dark Matter. I will review the recent and...
Ms
SİBEL BORAN
(Istanbul Technical University)
28/09/2017, 16:05
Cosmology & Astroparticle Physics
I will discuss quantum corrections during inflation in general.
And in particular, I will talk about our recent work on the one loop order corrections of gravitons to scalar mode functions which is conformally coupled to gravity.
Ms
Sukannya Bhattacharya
(Saha Institute of Nuclear Physics)
28/09/2017, 16:22
Cosmology & Astroparticle Physics
The dissipative mechanism in warm inflation scenario can provide the inflating universe with a warm exit to the radiation dominated era rather than a supercooled exit to a reheating phase. In this work, we constrain the model parameters for warm inflation from Planck 2015 data. In addition, the reheating era can be optimized by varying the number of $e$-folds of inflation. Best fit values for...
Dr
Sofiane Boucenna
(KTH Royal Institute of Technology)
28/09/2017, 16:22
Cosmology & Astroparticle Physics
Neutrino masses generated by physics around the weak-scale offer the advantage of testability, however from the model-building viewpoint they appear to be ad-hoc. I will present two classes of models which predict a radiative seesaw formula for neutrino masses and the presence of weakly interacting stable dark matter from (non-supersymmetric) SO(10) Grand Unified Theories. The model achieves...
Dr
Ville Vaskonen
(NICPB)
28/09/2017, 16:22
Cosmology & Astroparticle Physics
I will discuss the cosmological and astrophysical constraints on the fraction of the dark matter in primordial black holes (PBHs). First, I will describe a general method for extracting constraints for extended PBH mass functions from those for monochromatic ones, demonstrating that the constraints become more stringent in the extended case than the monochromatic one [1]. Then, I will discuss...
Ingmar Saberi
(Univ. Heidelberg)
28/09/2017, 16:25
String & Mathematical Physics
Recent developments in tensor network models (which are, roughly speaking, quantum circuits designed to produce analogues of the ground state in a conformal field theory) have led to speculation that such networks provide a natural discretization of the AdS/CFT correspondence. This raises many questions: just to begin, is there any sort of lattice field theory model underlying this connection?...
Ms
Deanna C. Hooper
(RWTH Aachen, TTK Institute)
28/09/2017, 16:39
Cosmology & Astroparticle Physics
Despite the increasingly more precise constraints on the amplitude and tilt of the primordial power spectrum, the shape of the inflaton potential is still largely unconstrained. This allows for potentials with oscillating contributions, such as the string theory motivated axion monodromy inflation. However, dealing with these models is computationally expensive, and as such analytical...
Dr
Viacheslav Emelyanov
(Karlsruhe Institute of Technology, Institute of Theoretical Physics)
28/09/2017, 16:39
Cosmology & Astroparticle Physics
Black holes can manifest themselves in local electromagnetic phenomena. This appears to be a consequence of the formation of the event horizon. In this talk, we shall discuss several local imprints of black holes in the far-from- and near-horizon region.
Dr
Wen Yin
(IHEP in Chinese Academy of Sciences)
28/09/2017, 16:39
Particle Phenomenology
We propose a scenario where both inflation and dark matter are described by a single axion-like particle (ALP) in a unified manner. In a class of the minimal axion hilltop inflation, the effective masses at the maximum and minimum of the potential have equal magnitude but opposite sign, so that the ALP inflaton is light both during inflation and in the true vacuum. After inflation, most of the...
Ro Jefferson
(AEI Golm)
28/09/2017, 16:45
String & Mathematical Physics
Motivated by recent studies of holographic complexity, we examine the question of circuit complexity in quantum field theory. We provide a quantum circuit model for the preparation of Gaussian states, in particular the ground state, in a free scalar field theory for general dimensions. Applying the geometric approach of Nielsen to this quantum circuit model, the complexity of the state becomes...
Dr
Tommi Tenkanen
(Queen Mary University of London)
28/09/2017, 16:56
Cosmology & Astroparticle Physics
We study production of primordial black holes (PBH) during an early matter-dominated phase. As a source of perturbations, we consider either the inflaton field with a running spectral index or a spectator field that has a blue spectrum and thus provides a significant contribution to the PBH production at small scales. First, we identify the region of the parameter space where a significant...
Enrico Morgante
(DESY)
28/09/2017, 16:56
Particle Phenomenology
In this talk I will analyze realizations of the relaxion mechanism in which quantum excitations of an auxiliary field slow down the relaxion and fix the Higgs vev at the electro-weak scale.
Dr
Laura Sagunski
(York University / Perimeter Institute)
28/09/2017, 16:56
Cosmology & Astroparticle Physics
The recent first direct detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory (LIGO) has marked the dawn of a new era for probing the theory of general relativity (GR) as well as possible modifications of it. To test gravity at extreme conditions, current and future gravitational wave detectors are targeted to explore merging binary systems of black holes...
Richard Eager
(Univ. Heidelberg)
28/09/2017, 17:05
String & Mathematical Physics
Pure N = 1 supersymmetric gauge theory with a simple gauge group G is widely believed to have k massive vacua, where k is the dual Coxeter number of the Lie algebra corresponding to G. The vacua are distinguished by the phase of the gaugino condensate. The appearance of the dual Coxeter number is a hint of the role of affine Lie algebras. A holomorphic twist of pure N = 1 gauge theory is known...
Dr
Subodh Patil
(Niels Bohr Institute)
28/09/2017, 17:13
Cosmology & Astroparticle Physics
We develop a unified description via the Boltzmann equation, of damping of gravitational waves by matter incorporating collisions. We identify two physically distinct damping mechanisms -- collisional and Landau damping. Maximal collisional damping of a gravitational wave, independent of the details of the matter collisions is significant only when its wavelength is comparable to the size of...
Dr
Kyohei Mukaida
(Kavli IPMU)
28/09/2017, 17:13
Cosmology & Astroparticle Physics
Primordial black holes (PBHs) are one of the candidates to explain the gravitational wave (GW) signals observed by the LIGO detectors. Among several phenomena in the early Universe, cosmic inflation is a major example to generate PBHs. In this case, the primordial curvature perturbation should be large enough to generate a sizable amount of PBHs, and thus we have several other probes to test...
Nayara Fonseca
(DESY)
28/09/2017, 17:13
Particle Phenomenology
The relaxion idea is a new alternative to justify the smallness of the Higgs mass. In this framework, the effective Higgs mass is scanned by a scalar field (the relaxion) starting at some large value which slowly decreases during inflation. We propose a UV completion for this mechanism in the context of warped extra dimension scenarios. In our construction, the warp factor can naturally...
Markus Dierigl
(DESY)
28/09/2017, 17:25
String & Mathematical Physics
We will discuss a full classification of toric F-theory models with gauge group SO(10) in six dimensions and a subclass of models that might lead to interesting phenomenological applications within 6d flux compactifications.
34.
Effects of equation of state in the Standard Model on the primordial gravitational wave spectrum
Ken'ichi Saikawa
(DESY)
28/09/2017, 17:30
Cosmology & Astroparticle Physics
The existence of relic gravitational waves (GWs) is one of the most important predictions of inflationary models, and the knowledge about their detailed spectrum will become indispensable in future direct detection experiments. In this work, we investigate thermodynamic properties of high temperature plasma composed of elementary particles of the Standard Model, and identify how such...
Dr
Mauro Pieroni
(Instituto de Fisica Teorica)
28/09/2017, 17:30
Cosmology & Astroparticle Physics
In my talk I discuss the phenomenology of models in which a pseudoscalar inflaton is coupled to some abelian gauge fields. The coupling between the inflaton and the gauge fields induces an instability in the theory which gives rise to a wide range of potentially observable signatures. In particular, I focus on the possibility of generating chiral gravitational waves in the range of direct...
Mr
Miguel Campos
(Max-Planck-Institut für Kernphysik)
28/09/2017, 17:30
Particle Phenomenology
We revisit the status of a Majorana fermion as a dark matter candidate, when a sequential Z' gauge boson dictates the dark matter phenomenology. Direct dark matter detection signatures rise from dark matter-nucleus scatterings at bubble chamber and liquid xenon detectors, and from the flux of neutrinos from the Sun measured by the IceCube experiment, which is governed by the spin-dependent...
Paul Oehlmann
(DESY)
28/09/2017, 17:45
String & Mathematical Physics
We present a full classification of SO(10) theories that can be represented as a toric hypersurface. These models generically exhibit additional Abelian, non-Abelian and discrete symmetries that can be used for phenomenological applications. We compute all charges and 6D multiplicities as well as anomaly coefficients base independently. These theories have a rich structure, such as non-Kodaira...
Mr
Moritz Platscher
(Max-Planck-Institut fuer Kernphysik)
28/09/2017, 17:47
Cosmology & Astroparticle Physics
With the first detection of a gravitational wave signal in September 2015 by the LIGO collaboration, a new era in physics has begun. Gravitational wave astronomy allows us to probe the contents and properties of our Universe in a completely new manner, accessing so far inaccessible scales and phenomena.
In this talk I will present one such phenomenon, dubbed gravitational wave...
Jose María Ezquiaga
(Instituto de Física Teórica UAM-CSIC)
28/09/2017, 17:48
Cosmology & Astroparticle Physics
The question of the origin of the dark matter (DM) remains as one of the most fundamental mysteries of modern physics. LIGO detections may be the first observations of a large population of primordial black-holes (PBHs) that could constitute today the dominant component of the DM. These PBHs arise naturally in models of Critical Higgs Inflation (CHI), where there is a peak in the spectrum...
Nelson Christensen
29/09/2017, 09:00
Ilya Mandel
29/09/2017, 09:40
Rafael Porto
29/09/2017, 10:20
Chiara Caprini
(APC Paris)
29/09/2017, 11:30
Dr
Thomas Jacques
(SISSA)
Particle Phenomenology
Displaced vertices are a striking yet under-exploited signature of beyond-SM physics at the LHC. Pseudo-Dirac DM includes two new Majorana fermions, the lighter of which is a DM candidate. The model gives the correct relic abundance while having a suppressed annihilation and scattering rate today, and without suppressing the LHC production rate. This evades current constraints while offering...
