CosmoPhys

astrophysics

New Location – This blog is no longer maintained here.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.

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New Location – This post is no longer maintained here and has been expanded and moved to this new location.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

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Two sets of White Paper submissions, Science and APC1, are available in response to the Astro2020 Decadal Survey. CSV files of info on them are available at that site. I took those source files and created searchable HTML pages with links to the PDF files for each paper. What's searchable is the paper title, the principal author and their institution, a short description of the paper, and (for the Science White Papers) the NASA ADS Bibcode record. The ADS data was extracted from an AAS Bulletin.

Each of the two searchable webpages has a link to the other, as well as to the source data. The webpages are self-contained with all the data included in the html file, which contains the javascript code for the searches and the CSS for styling.

The original purpose in doing this was because many of the submissions were not on the arXiv, and I wanted to see what else was available and also so the PDF file link were all on one page. In addition, though, the search feature has been very useful.

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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. ___

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This paper [arxiv: 1902.03261] is a current status review on improving systematics1 in SNe Ia distance measurements by combining optical with near-infrared (NIR) photometry. Though initially being done at low redshifts (z <= 0.04), there are plans to extend this work to higher redshifts2. The paper is authored by some of the more noted researchers in this area, e.g., Arturo Avelino and Robert Kirshner3. My goal here is a top-level summary, so that if you don't read the paper you'll hopefully get the gist of it, while also including helpful supplemental info. In a few cases, I added some font bolding for emphasis.

“This is significant for supernova cosmology because, along with photometric-calibration uncertainties, uncertain dust [extinction](https://en.wikipedia.org/wiki/Extinction_(astronomy) estimates and the intrinsic variability of SN Ia colors present challenging and important systematic problems for dark energy measurements. (pg2)”

“Recent work has demonstrated that SN Ia in the NIR are more nearly standard candles, even before correction for light curve (LC) shape or host galaxy dust reddening... Overall, a substantial body of evidence indicates that rest-frame LCs of SN Ia in NIR are both better standard candles than at optical wavelengths and less sensitive to the confounding effects of dust. When NIR data are combined with UBV RI photometry, this yields accurate and precise distance estimates. (pg2)”

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An excellent thread explaining the cosmic distance ladder with helpful graphics, by PhD candidate Sharan Banagiri: https://threadreaderapp.com/thread/1288230254151073792.html. The original source is from this tweet thread.

Some infographics about the cosmic distance ladder:

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