5th LISA Cosmology Working Group Workshop

Session

Talks and group discussions

11 juin 2018, 13:30

D101 (Physicum)

9. Consortium status

Martin Hewitson (AEI Hannover)

11/06/2018 13:30

10. ESA Perspectives

Paul McNamara (ESA)

11/06/2018 14:00

11. Consortium discussion

11/06/2018 14:30

Consortium-related discussion on:

• Publications & presentations policy
• Template for project proposals
• "SGWB characterization" WP

38. LISA work packages

Martin Hewitson (AEI Hannover)

11/06/2018 15:30

14. Multimessenger WP details

Elena Maria Rossi (Leiden Observatory)

11/06/2018 16:00

15. Standard sirens

Nicola Tamanini (AEI Potsdam)

11/06/2018 16:30

42. Astrophysics interplay and work packages

Lucio Mayer (Zurich)

12/06/2018 09:30

41. PBH: summary of the CERN workshop

Juan Garcia-Bellido (Universidad Autonoma de Madrid)

12/06/2018 10:00

6. Primordial Black Holes as Dark Matter

Tommi Tenkanen (Queen Mary University of London)

12/06/2018 11:00

I will revisit the most important cosmological and astrophysical constraints on the fraction of dark matter (DM) in primordial black holes (PBHs). I consider a variety of production mechanisms and mass functions for PBHs and discuss whether they can constitute the observed DM abundance or not. I also discuss how one can constrain the physics of the early Universe with the constraints on PBHs.

37. Local galactic measurements

Elena Maria Rossi (Leiden Observatory)

12/06/2018 11:15

17. Discussion and possible comments about structure formation

12/06/2018 11:30

18. LISA Data Challenge

Antoine Petiteau (APC - Université Paris-Diderot)

12/06/2018 13:30

• Intro
• Plans/status for data analysis for standard sirens
• Production of SGWB

19. SGWB data analysis for Radler

Riccardo Buscicchio (University of Birmingham)

12/06/2018 14:00

12. Bin reconstruction

Mauro Pieroni (Instituto de Física Teórica (IFT))

12/06/2018 14:30

47. SGWB parameter estimation

Nikolaos Karnesis (APC Paris)

12/06/2018 15:30

13. Probing the bispectrum of the SGWB

Valerie Domcke (DESY)

12/06/2018 15:45

50. Detector Geometries for a Chiral SGWB

Robert Caldwell (Dartmouth)

12/06/2018 16:15

40. Discussion on sky realisations, figures of merit etc.

12/06/2018 16:30

43. SGWB data analysis in LIGO/Virgo

Tania Regimbau (CNRS)

13/06/2018 09:30

44. Data analysis discussion

13/06/2018 11:00

24. Update on strings project

Lara Sousa (IA-Porto)

13/06/2018 11:30

30. Stochastic GW background from Cosmic Strings

Jose Juan Blanco-Pillado (IKERBASQUE and UPV/EHU)

13/06/2018 12:00

I will give a brief introduction to the theory of cosmic strings in the early universe and discuss recent progress in our understanding of the evolution of a cosmic string network using Nambu-Goto simulations. I will then discuss the production of gravitational waves from this network and how this leads to a prediction of an stochastic background of gravitational waves covering a wide range of...

36. Analytics of gravitational self-interactions of cosmic strings

Jeremy Wachter (UPV/EHU)

13/06/2018 12:15

We discuss an analytic approach to solving the problem of the gravitational self-interaction of cosmic strings. We demonstrate this approach on a simple toy model of string loops, and discuss how it might be applied to a string loop network.

33. Prospects for detecting gravitational waves from cosmic strings with LISA

Sachiko Kuroyanagi (Nagoya University)

13/06/2018 13:30

Cosmic strings are one-dimensional topological defects which may have been generated in the early Universe. LISA will be an excellent probe of cosmic strings as they emit strong gravitational wave bursts. In my talk, I will review the possibility of probing cosmic strings through detection of rare bursts as well as of a stochastic background, which consists of many overlapped bursts. I will...

3. Effect of the local population of superstrings on detection rates

Prof. David Chernoff (Cornell University)

13/06/2018 13:45

Cosmic superstrings of string theory differ from conventional cosmic strings of field theory, influencing the expectations for searches for relics from inflation. The universe's average density of cosmic superstrings can easily exceed that of conventional cosmic strings having the same tension by two or more orders of magnitude. The cosmological behavior of the remnant superstring loops is...

26. Phase transitions: signal update

Mark Hindmarsh (University of Sussex)

13/06/2018 14:00

45. Phase transitions project: BSM update

Jose Miguel No (Kings College London, IFT Madrid)

13/06/2018 14:15

27. More on the signal

Mikko Laine (AEC, ITP, U. Bern)

13/06/2018 14:30

1. Collider and gravitational wave signatures of the electroweak phase transition in the standard model effective field theory

Mikael Chala (IPPP Durham)

13/06/2018 15:30

We explore new-physics setups that at low energy exhibit a Higgs potential with sizeable higher-dimensional operators. We focus on the parameter regions promoting a first-order electroweak phase transition (FOEWPT). For weakly-interacting setups, we find that such regions are always tuned when the operators receive contributions from integrating out SU(2)_L singlets or triplets. The reason is...

49. Model discrimination in Gravitational Waves from Phase Transitions

Djuna Croon (Dartmouth)

13/06/2018 15:45

Besides the EWPT, various dark phase transitions could give an observable broken power-law spectrum at LISA. In this talk I will consider the opportunities for model discrimination, by examining the thermal parameters predicted in classes of models. These thermal parameters are functions of the parameters in the scalar potential, the quantum numbers of the scalar, and the couplings to...

20. Catalogues of sources (and webpage)

David Weir (University of Helsinki)

13/06/2018 16:00

22. Beyond the standard paradigms - status

Gianmassimo Tasinato (Swansea University)

14/06/2018 09:30

48. Cosmic structures and gravitational waves in ghost-free scalar-tensor theories of gravity

Purnendu Karmakar (University of Padova)

14/06/2018 09:45

5. The gravitational-wave luminosity distance in modified gravity

Michele Maggiore (University of Geneva)

14/06/2018 10:00

In modified gravity the propagation of gravitational waves is in general different from that in general relativity. As a result, the luminosity distance for GWs can differ from that for electromagnetic signals, and is affected both by the dark energy equation of state and by a function describing modified propagation. The effect of modified propagation in general dominates over the...

35. Testing quantum gravity with LISA

Gianluca Calcagni (IEM-CSIC)

14/06/2018 10:15

We briefly review whether and how some theories of quantum gravity could be tested by LISA, either with stand-alone data or in combination with other observations. In particular, we focus our attention on string theory, loop quantum gravity, asymptotic safety, nonlocal quantum gravity, and multifractional spacetimes. We stress the importance and meaning of following top-down approaches (from a...

46. Inflation project: short summary

Angelo Ricciardone (University of Stavanger)

14/06/2018 11:00

7. Primordial Gravitational Waves from Axion-Gauge Fields Dynamics

Matteo Fasiello

14/06/2018 11:15

I will first review an inflationary model that includes an axion coupled with SU(2) gauge fields. This setup can generate a chiral gravitational waves signal. I will then detail on how the parameter space of the theory supports a blue tensor spectrum and large tensor as well as scalar-tensor-tensor non-Gaussianities.

31. Chern-Simons gravitational term coupled to a scalar field during inflation

Giorgio Orlando (Dipartimento di Fisica e Astronomia, Padova)

14/06/2018 11:30

Chern-Simons gravity is a modified gravity theory where a term like $f(\phi) C \tilde C$ is added to the Einstein-Hilbert Lagrangian. Here $C$ symbolically labels the Weyl tensor, the trace-less part of the Riemann tensor. In this context $\phi$ can be both a scalar or a pseudo-scalar field and $f(\phi)$ is a generic scalar coupling function. Phenomenologically, it is interesting to study the...

4. Scalar field dark matter with spontaneous symmetry breaking and the 3.5 keV line

Catarina Cosme (University of Porto)

14/06/2018 11:45

We show that the present dark matter abundance can be accounted for by an oscillating scalar field that acquires both mass and a non-zero expectation value from interactions with the Higgs field. The dark matter scalar field can be sufficiently heavy during inflation, due to a non-minimal coupling to gravity, so as to avoid the generation of large isocurvature modes in the CMB anisotropies...

32. Production of gravitational waves during inflation

Lorenzo Sorbo (University of Massachusetts, Amherst)

14/06/2018 12:00

I will review mechanisms of production of matter during inflation that will in its turn lead to the generation of gravitational waves. These gravitational waves can be of relevance both for the phenomenology of the CMB and for gravitational interferometers.

25. Reminder: Source catalogue, parametrisation, figures of merit, project templates

14/06/2018 12:15

51. Future workshop; comments

Dr Germano Nardini

14/06/2018 12:25

39. Data generation for SGWB in Radler

Antoine Petiteau (APC - Université Paris-Diderot)

2. Gravitational Waves as a cosmological signature of the SM Higgs instability:

Prof. ANTONIO RIOTTO (UNIVERSITY OF GENEVA)

For the current central values of the Higgs and top masses, the Standard Model Higgs potential develops an instability at a scale of the order of $10^{11}$ GeV. We show that a cosmological signature of such instability could be the generation of gravitational waves detectable by LISA and we characterize their two- and three-point correlators.