New Location – This blog is no longer maintained here.

The cosmology researcher talks database app is a continuing work-in-progress on a collection that currently lists thousands of online talks by cosmology researchers intended for an audience of other researchers working in the field. The data is gathered from diverse sources (called 'series') that host talks from conferences, seminars, workshops, course lectures, summer schools, colloquia, etc.

This collection was started out of personal interest as a service to the cosmology community because no one site was found that comprehensively compiles such data from a wide range of sources. There are many sources available so this represents only a fraction of the total that's out there; still, it's a starter attempt to extend beyond what's otherwise available in one place.

New Location – This post is no longer maintained here and has been expanded and moved to this new location.

This is a simple list referencing examples of the work that I find interesting by some current early career physicists (primarily in cosmology and astroparticle physics). I may expand it later with more comments, but here it is for now:

Cosmologist Sunny Vagnozzi reviews 3 papers per week on cosmology and astroparticle physics on his blog. His PhD thesis, Cosmological searches for the neutrino mass scale and mass ordering, was selected for a Springer Thesis Award as one of the best PhD theses of 2019 and will be re-published as a book in the Springer Theses collection. He is active on twitter. Here is a list of video links to talks he presented at various conferences, seminars, etc. A talks page on his website includes talk slides in addition to video links. A one-page listing of all the papers he's reviewed on his blog is here along with topic tags links.

Marius Millea, @cosmic_mar on twitter, is currently a BCCP Fellow at Berkeley Center for Cosmological Physics. He is a member of the Planck and South Pole Telescope collaborations and an advocate for the Julia programming language (e.g., see CMSLensing.jl along with his other Julia github repositories). In 2019, he teamed up with his former thesis advisor Lloyd Knox to write the widely known paper in the field, The Hubble Hunter's Guide. Another impactful paper relating to the Hubble tension problem that he was an author on is Sounds Discordant: Classical Distance Ladder & ΛCDM-based Determinations of the Cosmological Sound Horizon. A more recent paper is about his work in developing a new CMB lensing analysis tool, Optimal CMB Lensing Reconstruction and Parameter Estimation with SPTpol Data. The video of a talk he presented at the Perimeter Institute about it is here. His full publication list is here and this is a list of video links to other talks he has given.

Deanna C. Hooper is currently a postdoc researcher at the University of Helsinki. One of her recent papers is [1910.04619] The synergy between CMB spectral distortions and anisotropies, which she summarized in a 20-tweet thread. More info and a link to her other papers here. She also has recorded a series of general talks about the universe on happs.tv and earlier on pscp.tv. In April 2020, she gave an interview presentation in the Cosmology Talk series on the topic: CMB spectral distortions are a prime untapped resource, based on the 1910.04619 paper.

This online-only conference featured 5 days of talks by cosmologists from 22-Jun-2020 to 26-Jun-2020. For anyone interested in the H0 tension problem, this is an excellent and highly recommended resource. Here are links to key resource information covering the conference.

A KITP-UCSB program running from Jan 6 to Mar 13, 2020 is an excellent resource for topics related to primordial universe cosmology (e.g., inflation, reheating (aka the Hot Big Bang), baryogenesis, non-gaussianity, dark sectors, cosmological sources of gravitational waves, Hubble tension, etc). The program agenda with links to videos and slides is here.

I'd like to point out an excellent overview talk from this program by Raphael Flauger on Feb. 28 that reviews Hubble measurement physics and results from each of the major determination methods and discusses current status on Hubble tension. The video for Flauger's talk is here. That page does not have the talk slides (at least not yet anyway) but the slides are available in PDF format here. Update: the slides are also now available on the KITP video page. Here is a PDF of the slides.

Link to paper: [2003.07355] Early Dark Energy Does Not Restore Cosmological Concordance, by J. Colin Hill, Evan McDonough, Michael W. Toomey, Stephon Alexander

Updates since this was originally posted:

• [2109.04451] The Atacama Cosmology Telescope: Constraints on Pre-Recombination Early Dark Energy , J. Colin Hill, et. al. Colin presents these results in a colloquium talk on 09-Sep-2021.
• In [2009.10740] Early dark energy is not excluded by current large-scale structure data a rebuttal is made and the authors “suggest that EDE still provides a potential resolution to the Hubble tension and that it is worthwhile to test the predictions of EDE with future data-sets and further study its theoretical possibilities.”
• Lead author Colin Hill was interviewed in a Cosmology Talk episode by Shaun Hotchkiss: Early dark energy doesn't make cosmology concordant again. Links to key parts of the video are available at the talk page.
• A detailed review of this paper was posted by cosmologist Sunny Vagnozzi on his blog here
• Follow-up paper: [2006.11235] Constraining Early Dark Energy with Large-Scale Structure, by Mikhail M. Ivanov, Evan McDonough, J. Colin Hill, Marko Simonović, Michael W. Toomey, Stephon Alexander, Matias Zaldarriaga. An astrobites article about it.

Background

Going back at least several years [1], but increasingly since late-2018 [2-7], there has been growing theoretical interest for the Hubble tension issue that suggests new physics models may be needed for the early universe prior to recombination that do not cause changes to late time cosmology, since that is tightly-constrained [4, 8].

For example, papers [2, 5] propose models for a new form of early dark energy (EDE) present at z ≳ 3000 that then dilutes away, resulting in a reduced sound horizon at decoupling. This results in a larger inferred $H_0$ value from CMB data versus Planck results, thus reducing the disparity between early and late time $H_0$ results.

These EDE proposals for resolving $H_0$ tension were characterized as being somewhere on the spectrum between “most plausible” [3] to “least unlikely” [4].

I had in mind to create a list of recent papers I found of interest that also had an author's talk available and in some cases a review. But after starting this post, I realized it's really so much better to have this data input into the recently initiated and excellent ResearchSeminars.org site, which has great listing and filtering capabilities and is becoming widely used. So I volunteered to the organizers of two cosmology talk series to input their data: Cosmology Talks on youtube hosted by Shaun Hotchkiss and CosmoConβ on youtube, aka Cosmology from Home. The target audience for these are researchers in the field. Now at the Research Seminars site, both Cosmology Talks and CosmoConβ are listed with all their current talks. Also, the Cosmology Talks series includes indexed links to the times of major sections of each talk as a convenience and helpful reference feature.

New developments since this post was originally created: videos of presentations at the KITP-UCSB conference Tensions between the Early and the Late Universe in mid-July 2019: (1) Tomasso Treu presentation: Time delay cosmography and the Hubble constant tension, and (2) Anowar J. Shajib presentation: Towards a 1% Hubble constant measurement with time delay cosmography. ___

This plot is Figure 1 from Di Valentino [2011.00246] A combined analysis of the $H_0$ late time direct measurements and the impact on the Dark Energy sector:

Slide from Adam Riess talk on 22-Feb-2021 using the above Di Valentino plot:

Below is a plot of the H₀ measurement data as of July 2019 and is taken from the paper Tensions between the Early and the Late Universe. This paper is a summary review of a KITP-UCSB workshop convened to bring together both experimental and theoretical researchers in the field to review and assess the current state of affairs and identify promising next steps at resolution of this issue.