INFLATION 2025 - Juan Garcia Bellido

The talk presents a compelling and well-structured argument for the role of primordial black holes in probing the quantum nature of inflation. Garcia-Bellido demonstrates deep expertise and provides a clear narrative from historical context to current research. The scientific content is rigorous, with careful attention to theoretical models and observational constraints. He appropriately acknowledges uncertainties, such as the metastability of the Higgs vacuum and the need for further data. The sources cited are relevant and credible, including his own influential papers and observations from Planck and LIGO. The talk is highly technical, assuming a strong background in cosmology and particle physics, but this is appropriate for the conference setting. The adéquation between title and content is adequate, as the talk focuses on inflation and PBHs. The presentation style is engaging, with the use of a movie to illustrate the potential. Overall, this is a high-quality scientific talk that offers valuable insights into a cutting-edge area of research.

The title is generic, but the content focuses on inflation and primordial black holes, which is consistent.

8/10

Talk by a leading cosmologist at a specialized conference, presenting original research and referencing established literature. The content is technical and based on theoretical models, with some speculative elements clearly identified.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 00:00Introduction and thanks to organizers; mention of 2005 conference.
• 02:00Discussion of the connection between inflation and particle physics, including the possibility of Higgs inflation.
• 05:00Historical overview of primordial black holes, starting with Hawking's 1971 proposal.
• 10:00Introduction of the 1996 paper with Linde and Wands on PBH production from inflation.
• 15:00Discussion of extended mass functions and clustering of PBHs, and their gravitational wave signatures.
• 20:00Presentation of the Higgs inflation model with non-minimal coupling to gravity.
• 25:00Explanation of the running of the Higgs self-coupling and the possibility of a near-critical point.
• 30:00Prediction of a plateau in the power spectrum at small scales, leading to PBH formation.
• 35:00Discussion of the effects of radiation pressure changes (e.g., QCD transition) on PBH formation.
• 40:00Mention of gravitational wave background and potential hints at nanohertz frequencies.

• Hawking, S. (1971). Gravitationally collapsed objects of very low mass. — Historical proposal of primordial black holes.
• Garcia-Bellido, J., Linde, A., & Wands, D. (1996). Density perturbations and black hole formation in hybrid inflation. — First paper on PBH production from inflation.
• Clesse, S., & Garcia-Bellido, J. (2015). Massive primordial black holes from hybrid inflation as the source of the LIGO events. — Paper suggesting PBHs with extended mass functions and clustering.
• Bezrukov, F., & Shaposhnikov, M. (2008). The Standard Model Higgs boson as the inflaton. — Original paper on Higgs inflation.
• Planck Collaboration (2020). Planck 2018 results. VI. Cosmological parameters. — Observational constraints on inflation parameters.

• Carr, B., & Kühnel, F. (2020). Primordial black holes as dark matter: Recent developments. — Review article supporting the idea of PBHs as dark matter candidates.
• Sasaki, M., Suyama, T., Tanaka, T., & Yokoyama, S. (2018). Primordial black holes—perspectives in gravitational wave astronomy. — Discusses the connection between PBHs and gravitational waves.

• Ali-Haïmoud, Y., & Kamionkowski, M. (2017). Cosmic microwave background limits on accreting primordial black holes.