Login

iTHEMS Cosmology Forum n°4 - Evolving Cosmos: new physical insights from new spectroscopic data

4–5 Aug 2025
RIKEN Wako Campus
Asia/Tokyo timezone

Contact

Contribution List

8 out of 8 displayed
Export to PDF
  1. 1. Keynote Talk - Dark energy and cosmology from DESI Data Release 2
    Dr Sesh Nadathur (University of Portsmouth)
    04/08/2025, 10:00

    More than 25 years after the discovery of the accelerated expansion of the Universe, the physical nature of dark energy remains elusive. The Dark Energy Spectroscopic Instrument (DESI) is the first of a new generation of “Stage-IV” cosmology survey experiments aiming to improve this understanding. By precisely mapping the positions of over 50 million galaxies and quasars, DESI is measuring the...

    Go to contribution page
  2. 2. Invited Talk - The Cosmological Constant Problem, Time-Varying Dark Energy, and DESI
    Dr Wen Yin (Tokyo Metropolitan University)
    04/08/2025, 13:30

    The cosmological constant problem, the most serious fine-tuning problem for the standard model parameters, remains a major puzzle, especially in light of Weinberg’s no-go theorem, which forbids natural solutions if dark energy is constant.
    Recent DESI observations suggest time variation in dark energy, opening a possible loophole. I present a model that realizes this idea to make the tuning...

    Go to contribution page
  3. 3. Poster Session (with Discussion & Coffee!)
    Tomoki Katayama (Sokendai), Yu Komiya (Yukawa Institute for Theoretical Physics, Kyoto University)
    04/08/2025, 14:30

    Yu Komiya - The phenomenology of domain walls and PBHs as probes of early universe dynamics
    Tomoki Katayama - Bi-Horndeski Theory

    Go to contribution page
  4. 4. Invited Talk - Detecting clustering dark energy using cosmological observations
    Dr Linda Blot (Kavli IPMU)
    04/08/2025, 15:30

    Clustering dark energy is a class of models in which the speed of propagation of the perturbations in the dark energy component is small compared to the speed of light, causing the perturbations to collapse on scales inside the horizon and affecting the process of cosmic structure formation. This presentation will go over the effects we expect to detect in cosmological observations and how we...

    Go to contribution page
  5. 5. Invited Talk - Baryon Acoustic Oscillations from DESI DR2
    Dr Andrei Cuceu (LBNL)
    05/08/2025, 10:00

    The Dark Energy Spectroscopic Instrument (DESI) is conducting a 5-year redshift survey of 40 million extra-galactic sources over 14,000 square degrees of the northern sky. One of its primary goals is to measure the cosmic expansion history across a wide range of redshifts using baryon acoustic oscillations (BAO). In this talk, I will present the latest DESI BAO results, which are based on the...

    Go to contribution page
  6. 6. Invited Talk - Untangling multi-probe hints for beyond-ΛCDM physics
    Dr Gerrit Farren (LBNL)
    05/08/2025, 13:00

    I will discuss the evidence for beyond-ΛCDM physics arising from the combination of different cosmological probes including DESI BAO, primary CMB and CMB lensing. I will review the information that can be extracted from the different probes. The tension between the parameters, particularly the matter fraction, inferred from individually fitting ΛCDM to each probes hints at the potential for...

    Go to contribution page
  7. 7. Invited Talk - Spacetime & gravity after/during Planck/DESI/SH0ES
    Dr Antonio De Felice (YITP)
    05/08/2025, 14:30

    Recently, there has been considerable debate regarding potential evidence for the dynamical nature of dark energy (DE), particularly in light of Baryon Acoustic Oscillations (BAO) measurements released by DESI survey. In this work, we propose an agnostic test that simultaneously constrains the dark energy (DE) equation of state (EoS) and probes the possibility of a transition between the...

    Go to contribution page
  8. 8. Panel Discussion
    05/08/2025, 15:45