19-23 September 2022
 Instituto de Física Teórica (IFT, CSIC-UAM), Madrid
 

See code of conduct at the bottom

Invited speakers

• Ana Achúcarro (Leiden U., Netherlands)
• Camille Bonvin (U. Geneva, Switzerland)
• William R. Coulton (CCA/Flatiron, USA)
• Olivier Doré (JPL/Caltech, USA)
• Eva-María Mueller (ICG/Portsmouth, UK)
• Marco Peloso (U. Padova, Italy)
• Ashley J. Ross (Ohio State U., USA)
• Fabian Schmidt (MPA/Garching, Germany)
• Anže Slosar (BNL, USA)
• Glenn Starkman (CWRU, USA)
• Obinna Umeh (ICG/Portsmouth, UK)
• Vincent Vennin (APC/Paris, France)

Topics

• PNG and 2-point functions

• PNG and bispectrum

• Light cone (GR) effects

• Large scale systematics

• Multi-tracers

• PNG from inflationary models

• PNG from the CMB

• PNG and gravitational waves

• PNG and CMB anomalies

Rationale

The largest scales of the Universe serve as a probe of fundamental physics such as the origin of cosmic structure and general relativity. Even though there is a growing consensus that cosmic inflation provides a powerful explanation for the origin of the cosmic large-scale structure (LSS), the landscape of competing inflationary models is huge. One of the main observables which can further constrain the range of currently allowed models of inflation is primordial non-Gaussianity (PNG), parameterized through fNL. Currently the tightest constraints on PNG come from the cosmic microwave background (CMB) bispectrum measured by the Planck collaboration. However, in the future, we expect to further tighten the constraints and reach, for example, a σ(fNL)<1 for the local type of PNG by studying the largest scales of the Universe where PNG would have left an imprint of a scale-dependent bias.

Synergies between different cosmological surveys will result in unprecedented measurements of the largest scales through multi-tracer methods, which will then enable us to reduce the effects of cosmic variance and significantly improve the constraints on PNG. At such scales, light cone effects (a.k.a. GR effects) also arise, which while providing complementary constraints on gravity, can potentially bias the measurements of PNG if not modeled consistently.

With upcoming Stage IV LSS experiments such as Euclid, SKA, DESI, SphereX and LSST, we will soon be ready to explore the Universe on gigaparsec scales, but this will require us to understand, with high accuracy, observational systematic effects which could a priori bias the clustering measurements.

Future Stage IV CMB experiments will also contribute, independently, to reducing the uncertainties on PNG, constraining also non-local types of non-Gaussianity through the CMB bispectrum. CMB lensing can also be combined with other LSS probes using the multi-tracer technique.

Furthermore, with the advent of gravitational wave (GW) interferometers, we will be provided with the possibility of measuring PNG through a completely new window and over a different frequency range. In particular, recent studies predict that appreciable levels of non-Gaussianity could be detected both in ground-based interferometers like LIGO-Virgo-Kagra and from space with LISA.

The aim of this workshop is to bring together world experts on primordial non-Gaussianity and other ultralarge-scale effects with different perspectives in order to prepare for the next generation of experiments. Potentially, the new experimental era will take us to the σ(fNL)<1 level, enabling us to differentiate between different families of inflationary models, e.g. single field versus multi-field inflation.

Logistics

The workshop will alternate plenary and contributed talks with generous time slots for discussions. We foresee a registration fee of 100€. Abstracts can be submitted until the end of June.

Code of Conduct

The Organization is committed to make this meeting productive,  safe, and enjoyable for everyone regardless of nationality, gender, race, sexual orientation, religion, political views, disability, and physical appearance. We will not tolerate harassment or misconduct in any form including, but not limited to, physical, verbal, and online actions.

The following guidelines are expected to be followed by everyone at the meeting.

1. Treat everyone with respect and consideration, this includes being respectful and mindful in your critique of ideas, and also to be mindful of your surroundings and your fellow participants. Do not insult or put down fellow attendees or staff.
2. Communication is expected to be appropriate for a professional audience with diverse backgrounds.
3. Harassment and sexist, racist, derogatory, or exclusionary jokes or comments will not be tolerated, neither are sexual language or imagery. Harassment includes (but it is not limited to) sustained disruption of talks or other events, inappropriate physical contact, sexual attention or innuendo, deliberate intimidation, stalking of any individual, and language bashing. It also includes offensive comments related to gender, sexual orientation, disability, physical appearance, race, religion or political views.

Any violation of these guidelines may result in the immediate removal of the offender from the meeting without warning and without refund. Furthermore, the offender’s action may be reported to the corresponding national institution. This will be at the sole discretion of the local organizing committee.

Participants asked to stop any kind of inappropriate behaviour are expected to comply immediately.

Anyone wishing to report any violation of these guidelines, is encouraged to speak to the organizers. The organization will grant confidentiality to both parties involved and will do everything in their power to restore a professional and safe environment for all as fast as possible.