10th–14th September 2018

Prague, Czech Republic

This school will feature a set of advanced lecture courses around the theme of gravity given by experts in the field. The courses will be aimed at advanced graduate students and young postdocs with a strong interest in the theoretical aspect of gravity and applications of the theory to modelling to the universe.

The school is co-organised by __CEICO__, a new institute at the Czech Academy of Sciences for research in cosmology, gravity and fundamental physics and the __Faculty of Mathematics and Physics of Charles University in Prague__. We are bringing eminent lecturers from the global community and hope to foster a diverse audience. There will be limited space for the presentation of a poster, but no submitted talks by participants are planned.

There is **no registration fee**, but participants should sort out their own accommodation (see __Venue and Accommodation__).

You can download the Gravity@Prague 2018 poster in __low__ and __high__ resolution.

Registration desks will be available from 8.30 to 9.00 and during coffee and lunch breaks on Monday 10 September.

LECTURER | TOPIC |
---|---|

Geoffrey Compère | Infrared Structure of Gravity [PDF] |

Matthias Gaberdiel | Higher-Spin Field Theories [PDF] |

Zohar Komargodski | Conformal Field Theory |

Samaya N. Nissanke | Gravitational Waves |

Antonio Padilla | The Cosmological Constant [PDF] |

Leonardo Senatore | Effective Field Theory of Large Scale Structure [PDF] |

Alexander Vilenkin | Inflation and the Multiverse [PPT] |

PROGRAMME | Monday 10/09/2018 |
Tuesday 11/09/2018 |
Wednesday 12/09/2018 |
Thursday 13/09/2018 |
Friday 14/09/2018 |
---|---|---|---|---|---|

9:00-10:30 | EFT-LSS | GW | CC | IR-GRAV | IR-GRAV |

10:30-11:00 | BREAK | ||||

11:00-12:30 | EFT-LSS | EFT-LSS | CC | CC | IR-GRAV |

12:30-14:00 | LUNCH | ||||

14:00-15:30 | GW | CFT | CFT | HS | INF-MUL |

15:30-16:00 | BREAK | ||||

16:00-17:30 | GW | CFT | FREE | HS | HS |

There will be two poster sessions during the school. On Tuesday 11/09 and Thursday 13/09, posters will be set up before the start of the lectures and the authors of the posters will be available during coffee and lunch breaks to discuss their work.

**Perseas Christodoulidis **(U. of Groningen, Netherlands)

*Angular inflation in multi-field α-attractors*

We explore the dynamics of multi-field models of inflation in which the field-space metric is a hyperbolic manifold of constant curvature. Such models are known as α-attractors and their single-field regimes have been extensively studied in the context of inflation and supergravity. We find a variety of multi-field inflationary trajectories in different regions of parameter space, which is spanned by the mass parameters and the hyperbolic curvature. Amongst these is a novel dynamical attractor along the boundary of the Poincaré disc which we dub "angular inflation". We calculate the evolution of adiabatic and isocurvature fluctuations during this regime and show that, while isocurvature modes decay during this phase, the duration of the angular inflation period can shift the single-field predictions of α-attractors.

**José Ricardo Correia **(Inst. de Astrofísica e Ciência do Espaço / Fac. de Ciências da U. do Porto, Portugal)

*Cracks in the sky: cosmic string evolution with CUDA*

Cosmic strings and other topological defects arise naturally in many proposed theories of new physics beyond the standard model. Simulating these objects with high-enough resolution and adequate dynamic range for both analytical studies and future observational searches (CORE and LISA), might require unfeasible amounts of time and/or hardware resources. In fact, this bottlenecking is already a problem. Since cosmic string simulations make use of traditional processors (either through distributed or shared memory architectures), a possible solution to this problem is to exploit more unconventional superscalar architectures, such as Graphics Processing Units, since their higher theoretical performance ceilings can be of benefit. We present a field-theory cosmic string simulation, based on a simple local U(1) model (Abelian-Higgs strings) optimised for Graphics Processing Units, based on the discretisation of [Phys. Rev. D75 065015, 2007, Phys. Rev. D96 no.2 023535, 2017]. We showcase a summarised overview of the implementation, and its performance and bottlenecks, alongside a comparison of averaged network quantities to what is found in the literature.

**Maxim Fitkevich **(INR RAS & MIPT Moscow, Russia)

*Dilaton gravity with a boundary: from unitarity to black hole evaporation*

We point out that two-dimensional Russo-Susskind-Thorlacius model for evaporating black holes is locally equivalent - at a full quantum level - to Jackiw-Teitelboim gravity that was recently shown to be unitary. Globally, the models differ by a reflective spacetime boundary added in the RST model. Introducing local and manifestly covariant condition at the boundary, we develop consistent mean-field description of evaporating RST black holes based on local equivalence between RST and unitary JT models. Our solutions still fail to resolve the information recovery problem implying that either the boundary makes the RST model fundamentally inconsistent or the mean-field approximation breaks down during the evaporation process.

**Ernesto Frodden **(U. Católica de Chile, Chile)

*Surface Charges in BF Theories*

To find invariant characterizations of solutions in gauge theories is a challenge. A century ago Emmy Noether showed that physical symmetries imply the existence of invariants named charges. We review a generalization of Noether result for gauge theories : Surface charges. A (re)derivation of the respective formulae for a series of gravity theories (Einstein-Cartan, Lovelock, Chern-Simons, and BF theories) can be done. In this talk we focus on the so-called BF theories and, as an application, we compute surface charges for the Taub-NUT solutions. The results are contrasted with recent literature.

**Florian Hopfmueller **(Perimeter Inst. for Theor. Physics, Canada)

*Null Conservation Laws for Gravity*

We give a full analysis of the conservation along null surfaces of generalized energy and supermomenta, for gravitational systems enclosed by a finite boundary. In particular, we interpret the conservation equations in a canonical manner, revealing a notion of symplectic potential and a boundary current intrinsic to null surfaces.
This generalizes similar analyses done at asymptotic infinity or on horizons.

[FH, Laurent Freidel, Phys.Rev.D97 (2018) no.12, 124029].

**Darsh Kodwani** (U. of Oxford, UK)

*A self-consistency check for unitarity and its implications for Hawking radiation*

Quantum mechanics is a unitary theory. What is often unstated is that only the full quantum system is expected to evolve unitarily in time. In reality we never treat the entire system we are dealing with as a quantum system and thus it is natural to ask when does a quantum sub-system evolve unitarity. We show that there are some very basic sub-systems which may evolve non-unitarily and then discuss why this is particularly problematic for black holes. In particular we build an analogy between the double slit experiment and Hawking radiation to show that the evolution of Hawking radiation, from near the horizon to null infinity may not evolve unitarily, thus potentially being a solution to the black hole information paradox.

**Scott Melville** (Imperial Coll., London, UK)

*To UV, or Not To UV: Constraining Effective Field Theories for Gravity and Cosmology*

Effective field theory techniques are so successful because they decouple complicated high energy physics from low energy observables. This is particularly important for gravity, in which often no explicit UV completion is known. However, not all UV information is lost at low energies: certain physical properties (like causality, locality and unitarity) become non-trivial constraints on the low energy physics. In this talk, I will demonstrate how the existence of a sensible UV completion can guide our IR model-building, and illustrate the impact of these "positivity constraints" with some simple field theories for dark matter, dark energy and modified gravity.

**Poulami Nandi **(Indian Inst. Tech., Kanpur, India)

*Large D gravity and charged membrane dynamics with nonzero cosmological constant*

We have found a class of dynamical charged "black-hole" solutions to Einstein-Maxwell system with a non-zero cosmological constant in a large number of spacetime dimensions. We have solved up to the first sub-leading order using large D perturbative technique. Large D is a perturbative scheme where the inverse of the number of dimensions (D) serves as the perturbation parameter. The effect of the black hole/brane (possessing an event horizon) gets confined to a region, called the membrane region, of a thickness of order (1/D) around the event horizon, irrespective of the asymptotic geometry. The membrane is dynamical with a velocity field on it. The dynamics of the membrane are entirely governed by membrane equations. The simplification due to large D scheme is that the nonlinear coupled partial differential equations (Einstein equations) get reduced to coupled ordinary differential equations (membrane equations). We can also generate new perturbative black hole solutions using the large D technique. We have solved for the charged black hole in AdS/dS up to first subleading order. The dual membrane carries a charge density field along with the velocity field for a charged black hole. The consistency of the analysis is checked by calculating the quasi-normal mode frequencies from our membrane equations. It matches well with the results obtained purely from the gravitational analysis.

**Makoto Narita **(Nat. Inst. of Technology, Okinawa College, Japan)

*Mathematical Aspects of Inflationary Cosmology*

We show a global existence theorem for Gowdy symmetric spacetimes with a positive potential as a model for inflationary cosmology from string/M-theory. Also, asymptotic behaviour of the spacetimes is investigated. Asymptotically velocity terms dominated solutions near the initial singularity are constructed and the future asymptotic behaviour of the spacetimes is analysed. These results are support the validity of the BKL, cosmic no-hair and strong cosmic censorship conjectures.

**Atsushi Naruko** (Tohoku U., Japan)

*On Lorentz-invariant massive spin-2 theories*

In this poster, we construct Lorentz-invariant massive spin-2 theories in a flat space-time. Starting from the most general action of a massive spin-2 field whose Lagrangian contains up to quadratic in first derivatives of a field, we investigate new possibilities by using the Hamiltonian analysis. By imposing degeneracy of the kinetic matrix and the existence of subsequent constraints, we classify theories based on the number of degrees of freedom and constraint structures and obtain a wider class of Fierz-Pauli theory as well as (partially) massless theories, whose vector and/or scalar degrees of freedom are absent. We also discuss the relation between our theories and known massive/massless spin-2 theories.

**Mohammad Nouri-Zonoz** (U. of Tehran, Iran)

*General relativistic analogues of Poisson’s equation and gravitational binding/dispersing energy*

Employing the quasi-Maxwell form of the Einstein field equations in the context of gravitoelectromagnetism (GEM), we introduce a general relativistic analogue of Poisson’s equation as its natural outcome. It is shown that in the GEM formalism, apart from energy density and pressure, there is a third component, the gravitoelectromagnetic energy density, which not only contributes to the active mass density but also accounts for the gravitational binding/dispersing energy. This general relativistic analogue of Poisson’s equation is compared with another analogue introduced by Ehlers, Ozsvath and Schucking. Introduction of the cosmological constant and its effect on the active mass, are also discussed for both exterior and interior static spacetimes. In the stationary case, we have considered the Kerr metric with a special choice of an interior Kerr solution.

**Sebastian Schuster **(Victoria U. of Wellington, New Zealand)

*Analytic and Algebraic Analogue Space-Times from Electro-Magnetic Media*

The idea of analogue space-times is to provide an alternative approach to curved space-time physics (and its effects): Instead of observing or venturing to space, one can mimic the relevant behaviour with other physical systems - ideally in a laboratory. Depending on the precise incarnation of the curved space-time one wants to look at, this allows fundamentally different formalisms. Here we shall present two such formalisms arising in the context of electro-magnetic media: On the one hand, one can look for media mimicking the "raising of indices" of a (curved) vacuum metric as encountered in (microscopic) electro-magnetism. This is our example of what we call an "algebraic analogue". On the other hand, one can start with a curved space-time wave equation. Assuming its separability, we can compare one of the resulting ordinary differential equations with a one-dimensional Helmholtz equation with a varying refractive index. This, then, is an "analytic analogue". Analytic and algebraic analogues have different advantages and disadvantages which we shall describe and juxtapose.

**Yota Watanabe **(Kavli IPMU, the U. of Tokyo, Japan)

*Solving the flatness problem with an anisotropic instanton in Horava-Lifshitz gravity*

In Horava-Lifshitz gravity a scaling isotropic in space but anisotropic in spacetime, often called "anisotropic scaling", with the dynamical critical exponent z=3, lies at the base of its renormalizability. This scaling also leads to a novel mechanism of generating scale-invariant cosmological perturbations, solving the horizon problem without inflation. In this presentation we propose a possible solution to the flatness problem, in which we assume that the initial condition of the Universe is set by a small instanton respecting the same scaling. We argue that the mechanism may be more general than the concrete model presented here. We rely simply on the deformed dispersion relations of the theory, and on equipartition of the various forms of energy at the starting point.

**Shingo Akama **(Dept. of Physics, Rikkyo U., Japan)

*The effect of the spatial curvature on the early universe in the Horndeski theory*

Our universe is almost spatially flat, but very small spatial curvature is still allowed. If there is nonzero spatial curvature, it affects the dynamics of the early universe. In the poster session, I discuss the effect of the spatial curvature on inflation and nonsingular cosmologies in the Horndeski theory which is the most general second-order gravitational theory with a single scalar field. I firstly focus on the inflationary universe and show that the effect on the power spectrum of the gravitational waves generated during the inflationary phase does not depend on any detail of a scalar field in the Horndeski theory. I also explain the effect of the spatial curvature on instabilities of nonsingular cosmologies. In the previous work, it has been proven that all nonsingular solutions in a spatially flat universe are generically plagued with gradient instabilities in the Horndeski theory. In the session, I extend the result to non-flat universes and show that all nonsingular solutions in the Horndeski theory suffer from the instabilities in open models as well, whereas the solutions generally do not have the instabilities in closed models.

**Juan Leopoldo Cuspinera **(Durham U., UK)

*Higgs vacuum decay with large extra dimensions*

We examine the effect of large extra dimensions on black hole seeded vacuum decay using the Randall-Sundrum model as a prototype. Modeling the braneworld black hole by a tidal solution, we solve for the instanton on the brane and show that the action, remarkably, is still the difference in the (bulk) areas of the seed and remnant black holes. We estimate these areas, and compare to the Hawking evaporation rate, showing that small black hole seeds preferentially catalyse vacuum decay, however the parameter ranges do not allow for Standard Model Higgs decay from collider black holes.

**Alexander Ganz **(U. of Padova, Italy)

*Gravity in mimetic scalar-tensor theories after GW170817*

We derive the most general mimetic scalar-tensor theory assuming a healthy "seed" action and accounting for the constraints on the speed of propagation of the gravitational wave from the GW170817 event. By performing a full Hamiltonian analysis, we show that this model is free of instabilities if the Lagrange parameter *λ* is positive definite. This can be ensured by redefinition of the Lagrange multiplicator parameter via *λ* → *e*^{λ}. The conclusion is independent of additional minimally coupled "ordinary" (i.e. non-mimetic) matter (Ganz, Karmakar, Matarrese & Sorokin, in preparation). By analysing linear perturbations around a flat FLRW background in this model, we are able to obtain a suitable form of the Poisson equation which allows us to calculate the effective Newton’s constant felt by ordinary matter. We also consider two cases, where the effective Newton’s constant of the mimetic gravity deviates from the ΛCDM, and when it is indistinguishable from ΛCDM (Ganz, Bartolo, Karmakar & Matarrese, in preparation).

**Kerem Halicioglu **(Freie Universität Berlin, Germany)

*Determining the Earth’s gravity field using star images, and geodetic data in Istanbul*

Modelling gravity field of the earth in local and global scales requires precise observations with various methods (i.e. gravimetry, GNSS/Levelling, chronometric, and astro-geodetic) in geodetic applications. Geoid, which is a special gravitational equipotential surface, is considered as a datum for both engineering and research studies. Thus defining geoid with high precision requires the combination of different techniques through using uncorrelated data. Astro-geodetic technique produces deflection of the vertical components (DoV) that yield to determining geoid heights (the difference between the ellipsoidal and orthometric height). DoV components can be obtained using a specially designed instrument called digital zenith camera system (DZCS). DZCSs are being used in several studies in order to define high precision geoid especially in Europe. In 2015 the first DZCS of Turkey was designed and tested on a network, in order to get the DoV components, and the results were compared with global geopotential models. The DZCS is now upgraded with new sensors and being used in a new project aiming to model the local gravity field in Istanbul. This study presents the theory, the practice, and the the observables of the astro-geodetic technique through using star images, and geodetic data in Istanbul-Turkey. Furthermore, the accuracy of the recent observations is going to be discussed and further studies to improve the accuracy will be introduced.

**Akash Kumar Mishra **(Indian Inst. of Technology, Gandhinagar, India)

*Photon Sphere around dynamically evolving Black Holes*

Because of gravitational lensing effect, a black hole casts a shadow which can be one of the most compelling observational evidence for the existence of black holes. The size of the shadow around a stationary black hole is ultimately linked with the radius of the circular null orbits, known as photon sphere around the black hole. However, black holes are in general not stationary since they radiate and accrete matter and hence it is very tempting for one to understand how the photon sphere evolves when one goes beyond the stationary consideration. This talk would aim at presenting a generalization of the notion of photon sphere when the spacetime is dynamical. In particular, I will discuss the evolution of the photon sphere by modeling the spacetime with various dynamical metric Ansatz in the context of General Relativity and Gauss-Bonnet Gravity.

**Jan Novák **(Technical University in Liberec, Czech Republic)

*Causal set approach and other discrete world*

We review basic postulates of causal set approach to quantum gravity and we show the emergence of cosmological constant in this theory, which is in concordance with observations. Then is studied the notion of particles and ﬁelds. Formulation of physical objections against continuum-based theories follows afterwards. We introduce few open issues in this theory and we show one interesting mathematical problem from topology at the end, which we believe is deeply connected with discretization procedures.

**Stefan Palenta **(U. of Vienna, Austria)

*The generalised Szekeres class of plane gravitational waves*

I present a generalisation of the Szekeres class of colliding plane wave solutions obtained by means of an inverse scattering method for the hyperbolic Ernst equation. Instead of the collinear polarisation of the waves within the Szekeres class, the incoming waves feature a monotonically increasing phase angle in their characteristic Weyl tensor component and thus can be regarded as "circular polarised". These waves can occur with two different helicities, and interestingly the interaction properties differ dramatically for collisions of waves with the same or respectively opposite helicities. The class seams also to admit a limit of "circularly polarised impulsive waves".

**Ivan Rybak **(Inst. of Astrophys. and Space Sciences, Porto, Portugal)

*Collisions of cosmic strings with chiral currents*

We present an analytic study of cosmic superconducting chiral strings collisions in Minkowski space. We apply kinematic constraints to strings that are described by the effective Nambu-Goto action. In particular, we revisit the solution for chiral superconducting cosmic strings and demonstrate that the Y junction production for such strings is possible. We consider the collision of chiral current-carrying straight strings and obtain the "angle-velocity" region that allows the production of junctions. This study contribute to the understanding of the cosmic string network evolution.

**Canberk Sanli **(Phys. Dept., Bogazici U., Turkey)

*N=2 dyons revisited*

Although the low energy effective formalism of N=2 supersymmetric SU(2) Yang Mills theory is exactly known since the great achievement of Seiberg and Witten (Seiberg, 1994), the physical implications are still not complete, for example which lessons can be drawn for QCD being non-supersymmetric theory are not established (Lerche, 1998). Starting from the generic form of the prepotential of the N=2 supersymmetric SU(2) low energy effective action, we revisit the BPS solutions by studying the effective action on the vacuum manifold in the duality covariant formalism which makes the symplectic structure of the theory manifest and shows that complex local central charge function for the BPS solutions carrying mutually local charges satisfy Maxwell equations (Bleeken, 2012) with the aim to interpret the physical properties of the dyonic solutions. In particular, in this formalism, we investigate the role of attractor mechanism which is well-known in the supergravity literature (Ferrara, 1996), in order to find out the BPS charge spectrum in the low energy regime. We establish the attractor flows by assuming one single source and then show how to further generalize this model to include the mutually non-local charges as well which requires to modify the BPS equations due to breaking of the underlying harmonicity.

**Gizem Sengor **(Syracuse U., USA)

*Hidden Preheating*

Within the effective field theory formalism for cosmological perturbations, we consider derivative couplings between scalar reheating and inflationary perturbations and question if perturbations of both species can always appear together as the lightest degrees of freedom. We discover energy scales where the reheating perturbations contribute to the canonical momenta of inflationary perturbations, rather than to appear as individual degrees of freedom. We refer to these cases, where the reheating sector only assists the dynamics of the inflationary perturbations during preheating, as hidden preheating.

**Andrey Shkerin **(INR Moscow, Russia and EPFL, Switzerland)

*Gravity, Scale Invariance and the Hierarchy Problem*

Combining the quantum scale invariance with the absence of new degrees of freedom above the electroweak scale leads to stability of the latter against perturbative quantum corrections. Nevertheless, the hierarchy between the weak and the Planck scales remains unexplained. We argue that this hierarchy can be generated by a non-perturbative effect relating the low energy and the Planck-scale physics. The effect is manifested in the existence of an instanton configuration contributing to the vacuum expectation value of the Higgs field. We analyze such configurations in some theories encompassing the Standard Model and General Relativity. Dynamical gravity and a non-minimal coupling of it to the Higgs field play a crucial role in the mechanism.

**Michal Vraštil **(CEICO, Inst. of Physics, Prague, Czechia)

*Fast methods for N-Body simulations*

Because of a large amount of different models of modified gravity it is impossible to probe this huge parameter space through standard N-body simulations. It is therefore necessary to come up with new methods how to study modified gravities with reasonable accuracy. We present several approximate methods how to simulate growth of cosmic structures and show results of their accuracy.

**Yi-Peng Wu **(RESCEU, the U. of Tokyo, Japan)

*Signature of heavy physics in the primordial non-Gaussianity*

The decay of massive particles during inflation generates characteristic signals in the primordial non-Gaussianity if masses of these particles are larger than the Hubble scale during inflation. We investigate the bispectrum from the decay of a scalar particle that acquires a large effective mass due to its strong coupling with the inflaton field. While a derivative coupling of inflaton and a heavy field usually result in the equilateral type non-Gaussianity, we show that a class of non-derivative coupling can lead to novel shapes of bispectrum with an arbitrary peak value in between the squeezed and the equilateral limits.

**Beata Zjawin **(Nicolaus Copernicus University, Toruń, Poland)

*First observation with global network of optical atomic clocks aimed for a dark matter detection*

Astrophysical observations indicate that the Universe contains five times more dark matter than standard matter, however its nature still remains an unsolved mystery. Dark matter candidates like topological defects and oscillating massive scalar fields can be searched for by a single optical atomic clock. We describe the optical atomic clocks readouts analysis and provide a recipe for analysing data from transcontinental network made of already existing optical atomic clocks. We describe, basing on Very-Long-Baseline Interferometry (VLBI) procedures, how to correlate the data obtained from already operating optical atomic clocks to search for topological-defect dark matter. Furthermore, we discuss how to filter the readouts in order to restrict desirable frequency range and improve already existing limits on dark matter fields couplings to standard matter fields. We also show how to analyse the data from a network of many clocks to exceed previously reported limits on oscillating massive scalar fields couplings to standard matter.

NAME | INSTITUTION | COUNTRY |
---|---|---|

Shingo Akama | Rikkyo University | Japan |

Oscar Arandes | University of Barcelona | Spain |

Henk Bart | Max Planck Institute for Physics | Germany |

Klaus Bering | Masaryk U., Brno | Czech Republic |

Michal Bílek | Astronomical Institute of the Czech Academy of Sciences | Czech Republic |

Nadia Bolis | CEICO | United States |

Victor David Bosca Navarro | Heidelberg University | Germany |

Marcelo Calderon Ipinza | Pontificia Universidad Católica de Valparaíso | Chile |

Federico Capone | University of Southampton - STAG Research Center | United Kingdom |

Roberta Chiovoloni | Swansea University | United Kingdom |

Perseas Christodoulidis | University of Groningen | Netherlands |

José Ricardo Correia | Instituto de Astrofísica e Ciência do Espaço / Faculdade de Ciências da Universidade do Porto | Portugal |

Juan Leopoldo Cuspinera Contreras | Durham University | United Kingdom |

Elena De Paoli | CPT Aix-Marseille | France |

Pranab Jyoti Deka | University of Potsdam | Germany |

Federico Di Gioia | University of Rome "La Sapienza" | Italy |

Cristian Erices | National Technical University of Athens | Greece |

Kara Farnsworth | CEICO | Czech Republic |

Antonio Ferreiro | University of Valencia/CSIC | Spain |

Peter Filip | research scientist | Czech Republic |

Maxim Fitkevich | INR RAS & MIPT | Russian Federation |

Guilherme Franzmann | McGill University (currently at YITP) | Canada |

Ernesto Frodden | Universidad Católica de Chile | Chile |

Alexander Ganz | University of Padova | Italy |

Mina Ghodsi Yengejeh | Faculty of Physics Shahid Beheshti University | Islamic Republic of Iran |

Suvendu Giri | Uppsala University | Sweden |

Sebastian Golat | King's College London | United Kingdom |

Andrey Grabovskíy | Budker Institute of nuclear physics | Russian Federation |

Kerem Halicioglu | Bogazici University | Germany |

Katrin Hammer | Ludwig-Maximilians-Universität München | Germany |

Florian Hopfmueller | Perimeter Institute for Theoretical Physics | Canada |

Jiri Hosek | Dept. Theor. Physics, Nuclear Physics Institute, Rez | Czech Republic |

Ondřej Hulík | CEICO | Czech Republic |

Erik Jensko | University of Nottingham | United Kingdom |

Pavel Jiroušek | CEICO | Czech Republic |

Aris Katsis | National and Kapodistrian University of Athens | Greece |

Joe Kennedy | University of Edinburgh | United Kingdom |

Christiane Klein | Max Planck Institut für Kernphysik Heidelberg | Germany |

Darsh Kodwani | University of Oxford | United Kingdom |

Jan Kubíček | Faculty of Mathematics and Physics, Charles University. Institute of Mathematics, CAS | Czech Republic |

Martin Kuchynka | MÚ AV ČR | Czech Republic |

Ibere Kuntz | University of Sussex | United Kingdom |

Pavel Kůs | MFF UK | Czech Republic |

Fran Lane | Institute for Astronomy Edinburgh | United Kingdom |

Renann Lipinski Jusinskas | CEICO | Czech Republic |

Shubham Maheshwari | Univ Groningen | Netherlands |

Francisco Jose Maldonado Torralba | University of Cape Town | South Africa |

Hiroaki Matsunaga | Czech Academy of Sciences | Czech Republic |

Scott Melville | Imperial College London | United Kingdom |

Poulami Nandi | INDIAN INSTITUTE OF TECHNOLOGY KANPUR | India |

Makoto Narita | National Institute of Technology, Okinawa College | Japan |

Atsushi Naruko | Tohoku University | Japan |

Mohammad Nouri-Zonoz | University of Tehran | Islamic Republic of Iran |

Jan Novák | Technical University in Liberec | Czech Republic |

Roberto Oliveri | Universite Libre de Bruxelles (ULB) | Belgium |

Stefan Palenta | University of Vienna | Germany |

Jong-Dae Park | Kyung Hee University | Korea, Republic Of |

Sohyun Park | CEICO | Czech Republic |

Sabir Ramazanov | CEICO | Czech Republic |

Israel Ramirez | KU Leuven/ Universidad Andres Bello | Chile |

Seyed Meraj Mosavi Rasouli | Universidade da Beira Interior | Portugal |

Miguel Riquelme | CECs | Chile |

Ivan Rybak | INSTITUTE OF ASTROPHYSICS AND SPACE SCIENCES-Porto | Portugal |

Reza Saffari Khomirani | University of Guilan | Islamic Republic of Iran |

Canberk Sanli | Bogazici University | Turkey |

Sebastian Schuster | Victoria University of Wellington | New Zealand |

Gizem Sengor | Syracuse University | United States |

Andrey Shkerin | EPFL | Switzerland |

László Ábel Somlai | MTA Wigner RCP, Pécsi Tudományegyetem | Hungary |

Stefano Speziali | Swansea University | United Kingdom |

Michal Šumbera | Nuclear Physics Institute CAS | Czech Republic |

Agus Suroso | Theoretical Physics Group, Institut Teknologi Bandung | Indonesia |

Otakar Svítek | Charles University | Czech Republic |

Tayebeh Tahamtan | Charles University | Czech Republic |

Fred Tomlinson | University of Edinburgh | United Kingdom |

Caner Unal | CEICO | Czech Republic |

Nezihe Uzun | Ústav teoretické fyziky MFF UK | Czech Republic |

Orestis Vasilakis | CEICO | Czech Republic |

John Adrian Villanueva | National Institute of Physics, University of the Philippines Diliman | Philippines |

Jakub Vosmera | CEICO | Czech Republic |

Michal Vraštil | CEICO | Czech Republic |

Yota Watanabe | Kavli IPMU, The University of Tokyo | Japan |

Yi-Peng Wu | RESCEU, the University of Tokyo | Japan |

Adamantia Zampeli | Charles University | Czech Republic |

Ondřej Zelenka | Charles University | Czech Republic |

Beata Zjawin | Nicolaus Copernicus University | Poland |

Lectures will be held at the Faculty of Mathematics and Physics of Charles University in Troja, Prague 8.

The closest bus stops are Pelc Tyrolka (bus line 112) and Kuchyňka (bus line 201). The closest station is Nádraží Holešovice, reached by the Metro Line C (red line) and several tram lines, from which one can take the bus 201 or walk about 1.5km across the Troja Bridge (Trojský Most) or the Bridge of the Barricade Fighters (Most Barikádníků). Google Maps has the Prague public transportation timetables and can be reliably used to gauge travel time when choosing accommodation.

Participants are expected to sort out their accommodation; we recommend to book your stay well in advance as September is still high season in Prague.

Tourist information about Prague and the Czech Republic can be found on many comprehensive resources online, such as Wikivoyage (__Czech Republic__ and __Prague__) and the __official Prague tourist website__.
More about events and culture in Prague can be found on __expats.cz__ and __GoOut__.

A welcome reception will be organised at the bistro of the __Jatka 78 theatre__ on Sunday, 9 September at 18:00, the day before the start of the lectures.

A social dinner will be held at __Pavilon Grébovka__ in the evening of Wednesday 12 September.

These two events will be free to participants. Significant others are welcome at own cost (850 CZK for the reception and 1000 CZK for the dinner).

Registrations are now closed.