I'm a dad; I’m a professor doing cosmology at Duke U. and I have some opinions about basketball.
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Big congrats to the TRGB-SBF team for their new H0 result! What’s additionally important about this is that it’s 1) independent of Cepheids, 2) independent of SN Ia, 3) independent of SH0ES and higher in H0 4) yet another agreement between prior HST results and JWST in measuring H0. This was one of the two external papers I’ve been waiting for with local H0 measurements to officially call it the Hubble Crisis. arxiv.org/abs/2502.15935
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Lately, there have been different reports about the Hubble Tension from JWST, with different teams and methods. It’s been hard to follow. But initial sample sizes were small so in a new paper we combined, for the first time, all measurements to date, includes 5 JWST programs, and it makes a pretty clear picture. arxiv.org/abs/2408.11770 🧵
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Taught my first class online this morning. Was going really well, until one student started doodling a pink house on the lecture slide without realizing everyone else could see😂. @DukeU @DukePhysics #remotelearning
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Holy **** H0LICOW!!! arxiv.org/abs/1907.02533. SHARP and H0LiCOW use AO+HST to get H0=76.8+-2.6 for 3 lenses. I’m getting goosebumps...
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SH0ES team reports 1.9% measurement of Hubble constant, based on new @NASAHubble observations of Cepheids and improved distance to LMC (just published by Araucaria group in @nature). Tension with predictions from early Universe (based on @Planck CMB+LCDM) increased to 4.4 sigma!!
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Cosmology in 2025 will be really exciting so I put together a ‘Top 2025 Cosmology Papers I’m Looking Forward To’. Ordered from nearest to furthest, and guessing a bit on when they’ll come out. A fun 🧵
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Hi @AliciaAarnio, my name is Dan Scolnic and I'm an astro professor in the Physics Department at Duke, please reach out if I can help in any way, we're not that far away here in Durham.
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Whoa- SH0ES gets re-analyzed a ton, but always using our photometry. This team (independently/surprisingly) went to raw HST pixels, intentionally chose different method at each step. Gets same answer as SH0ES to 1% in H0 & same uncertainty. In ApJ/arxiv: arxiv.org/abs/2102.12489😌
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So last night arxiv.org/abs/2105.11461 claimed could remove H0 tension because of dust. I’m all for us discovering that dust is really weird, but paper changes H0 by changing Black Body physics for Cepheids, not dust. What has been discovered (something/nothing)? A thread.
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One of coolest things in science is when signal goes from 🤔 to 💥. Huge congrats to @ESAGaia team, see this figure that shows huge difference between DR2 v. DR3. Here is new paper by SH0ES team (arxiv.org/abs/2012.08534) that uses new Gaia data, gets same H0 with more precision.
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Just got letters that me and @michaeltroxel are getting tenure! It's been such a fun ride getting to help build a cosmology program @DukePhysics and so wonderful getting to do science with so many amazing collaborators. 🥳
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Arguably one of biggest curiosities about Hubble Tension is why TRGB+Supernova gives values between the two tentpoles of Tension, 67 and 73. We have new paper from CATS team doing 🍜 to 🥜🥜 analysis of TRGB+SN and get H0=73.2+-2.0 km/s/Mpc. How/why? A 🧵arxiv.org/abs/2304.06693
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This is wrong (see here they use my team's Pantheon+ data). Somehow they parameterize multiple models to match the data almost exactly the same, even though very different physics behind each one. This is ~impossible to do unless they add so many non-physical parameters to their CCC and TL models that all they have come up with is an arbitrary fitting function, which has no predictive power about the age of the universe.
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Thanks to all my wonderful collaborators for making the work so much fun. (And yeah, I asked the confused photographer to put his ladders in the shot, cause you know, distance ladder..I'll show myself out).
Congratulations to @DukePhysics cosmologist Dan Scolnic on receiving an Early Career Research Program award from @DOEScience!
His research topic: Reducing Top Systematic Uncertainties in Cosmological Analyses with Type Ia Supernovae and Contaminated Photometric Samples
ALT Dan Scolnic smiling
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New paper out that I’m so excited to share—thanks to @desisurvey we have a new view of the Hubble tension! DESI calibrated its Hubble diagram to the Coma cluster. If Coma is at the distance people have measured it to be—for decades—that is a serious problem for LCDM. But is it? We checked… “The Hubble Tension in our own Backyard: DESI and the Nearness of the Coma Cluster” arxiv.org/abs/2409.14546 (1/9)
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Some thoughts on a really exciting but also very confusing last week of cosmology. We have a standard model of cosmology, LCDM, we now have multiple tensions, but what we don't have is a clear story. A 🧵.
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Triplet of papers tonight on arxiv from JWST improving the distance ladder and H0! Bottom line: from many methods it doesn’t look like the source of the Hubble Tension is in the second rung of the distance ladder. See 🧵 below.
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Hi @Andercot, I was one of the co-leads of the Pantheon+ supernova analysis that these authors try to re-analyze here. I can say that this analysis is very confusing, and I can't see any piece of it that has statistical significance. Normally, if one tries to propose a new model, they show residuals to that model versus (our) best fit. In this analysis, a number of the parameters they release don't make any sense.
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Two new interesting H0 measurements on arxiv last night: arxiv.org/abs/2408.03660 (Boubel et al.). - and arxiv.org/abs/2408.03474 (Lee et al. - @abigail_j_lee). The first does new Tully-Fisher and gets high H0, the second does JAGB and gets lower. Interestingly, I think both support the hubble tension story after you unpack them. A wonky thread.
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Busy week - new paper by George Efstathiou pointing out potential systematic uncertainties in the DES-5yr supernova analysis and its constraints on evolving dark energy. I have some thoughts, but wanted to start with a genuine appreciation of George. arxiv.org/abs/2408.07175
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Super grateful and incredibly excited to be named
a 2019 #PackardFellow !! I’ll be working on supernovae, dark energy, and the cosmic distance ladder. See the official announcement from the @PackardFdn here: bit.ly/PFFellows2019 - some thanks below->
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Yesterday-
[LIGO]: We see something! It’s roughly in that quarter of the sky😬
[Optical Follow-up Community]: Hold my beer.
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Now Mark Reid drops another huge result from Megamaser project H0=74.8+-3.1. This week is too much. Go home H0, you're drunk. #KITP_H0tTakes
Mark Reid (cfA) share their work on measuring H0 via Megamaser! The joint result they got is H0=74.3+/-3.1 km s^-1 Mpc^-1 #KITP_H0tTakes One more point for high-H0 campaign!
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Thank-you so much to @SloanFoundation for this awesome honor! And thanks to @DukePhysics and all my wonderful collaborators. In return for this gift, I will see what I can do to get a really amazing sky survey named after the @SloanFoundation 😊.
Introducing… the winners of this year’s Sloan Research Fellowship! These extraordinary researchers represent some of the most exciting young minds working today—and we are thrilled to support them. Meet the winners here: sloan.org/fellowships/2022-F… #SloanFellow
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Whoa - new paper by @jcolinhill and @ACT_Pol collaboration finding evidence for early dark energy at >3sigma ( arxiv.org/abs/2109.04451 ) If true, this explains Hubble tension. @jcolinhill - please tweet thread.
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Very excited to invite people to a webinar this Thursday pm 12 ET on new SH0ES H0 result and Pantheon+ updates. On SH0ES side, this is our biggest paper since 2016. If interested, please register for webinar on link below: duke.zoom.us/meeting/registe…
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Latest H0 news - paper led by W. Yuan finds blending error in external catalog used in latest Freedman et al. 2019 TRGB result. Not CCHP's data, just old catalog, but essential for their extinction estimate and fix changes their H0: 69.8 -> 72.4. arxiv.org/abs/1908.00993
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Very interesting new H0 result by Vogl et al. - this uses the Expanding Photosphere Method with Type II supernovae (spoiler alert H0=74.9 +/- 1.9). This is an old approach to measuring distances but here with an impressively rigorous refresh and a distance ladder-free measurement [arxiv.org/abs/2411.04968]. 🧵
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Congrats to SBF team (Blakeslee et al.) for getting out huge work (arxiv.org/pdf/2101.02221.pdf) using surface brightness fluctuation distances to measure H0. New local distance ladder measurement, doesn't use any supernova or SH0ES data, and gets 73.3 ± 0.7 ± 2.4 km/s/Mpc. Cool.
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I'm excited to advertise a new professor opening at North Carolina Central University (in Durham NC). NCCU is an HBCU and the position would be to help start an astrophysics program there. This would also be an adjunct professor with Duke and funding is already in place to work on the Roman Space Telescope: jobs.nccu.edu/postings/31307
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Wow - this H0 ride will not let up. 'CF 4: Calibration of Optical and IR Tully-Fisher Relations': A preliminary determination of the Hubble Constant from the distances and velocities of the calibrator clusters is H0=76.0+-1.1(stat.)+-2.3(sys.) km/s/Mpc.' arxiv.org/abs/2004.14499
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Adam Riess told me about this Nature Review he was writing 'The Expansion of the Universe is Faster than Expected' - arxiv.org/pdf/2001.03624.pdf - and I said 'Just show me the abridged version.' (I'll show myself out.)
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Thank-you @AAS_Office for this award and opportunity! I am more than slightly petrified for the talk, but I promise I will make the plot labels on my slides gigantic! I’ve got a little over a month to come up with a banger of an opening joke 😀
The @AAS_Office is delighted to award Prof. Daniel Scolnic (@DScol) with the Fred Kavli Plenary Lectureship for groundbreaking work on Pantheon+SH0ES. Prof. Scolnic will kick off a phenomenal #AAS242 this June in Albuquerque!
aas.org/press/aas-names-dani…
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New paper on 'supernova siblings' led by Arianna Dwomoh and @erikpeterson23 (pic here of Arianna pressing submit to arxiv). This is @DukePhysics Arianna's *second* first-author paper as an undergrad 🤩 Explanation 🧵 below.
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Congrats to @desisurvey on very exciting cosmology result! Having read paper and seen some press about it, I do find it interesting/odd/flattering? that for a Stage IV dark energy BAO experiment, they focus so much on type Ia supernovae, so here's a thread on that aspect (1/6)
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Really nice workshop summary of last week's meeting by Verde, Treu and Riess - arxiv.org/abs/1907.10625. Great to capture this moment in one plot for the record.
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Really important H0 development from the quasar strong lensing community at Barcelona cosmo meeting. Recap - they were consistently getting high H0 values from their measurements, ~73+/-1.8, but decided to see how H0 changed if they freed assumptions about how mass is distributed in galaxies, adding velocity dispersions to constrain that. This made their H0 swing to possibly lower value. Now it turns out these velocity dispersions they used had an error–-the size of the Hubble tension! A 🧵
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Jeez. First observations and magnitude measurement of SpaceX’s Darksat arxiv.org/pdf/2003.07251.pdf -> Special 'darkening treatment' makes brightness go from 6.69 mag in g band to 7.57 mag (at 976km), essentially from 'terribly bright' to...'terribly bright' 😟 #Starlink
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The famous Bob Kirshner with a bunch of his academic grandchildren and great-grandchildren.
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It's been a week. One thing I hope came across from new Pantheon+SH0ES results is that we really listened to challenges/criticisms/suggestions of the community and tried to address as many as possible. The papers really benefited from having so many different things to check.
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Had a great time visiting Princeton Astrophysics and @the_IAS these last couple days. So much awesome research there. Here is my touristy photo trying to hear what Einstein and Oppenheimer were really talking about.
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My new grad student, Maryann Fernandes, told me her life passion is to work on asteroids. So, after ~20 years working on cosmology, here is my first foray into planetary defense: "Measuring the Distances to Asteroids from One Observatory in One Night with Upcoming All-Sky Telescopes" 🧵arxiv.org/abs/2502.07881
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This is really hard to understand. Roman is at the finish line, on schedule and in budget. @ValerieFoushee - have you seen this?
White Budget proposal includes a TWO-THIRDS cut to NASA Astrophysics and completely cancels - the already assembled (!) - Roman Space Telescope...
arstechnica.com/space/2025/0…
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Very interested to see status report posted by CCHP on three-probe measurement of H0 (H0=70+-1+-1). On one hand, what they actually measure, distances to SN Ia hosts with JWST 3 ways, agrees super well with the previous HST Cepheids (SH0ES) (see below). On other, lower H0 can be explained by a small+skewed SN selection and low uncertainty seems to come from a puzzling error analysis. Excited to 🤿! :) arxiv.org/abs/2408.06153
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Proud of @DukePhysics superstar grad student Rebecca Chen for new paper trying to combine photo-z's with supernova cosmology - what I think is hardest challenge of LSST era for SNe! arxiv.org/abs/2407.16744
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My favorite moments being a research advisor are when we are all eating together, and people start laughing/teasing about some super obscure science point. It's a joy. @DukePhysics
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The main premise of the distance ladder is neither physics nor astrophysics change between rungs because galaxies (identically selected) don’t know which rung they are on. Over the last couple of years, some have proposed breaking that premise to resolve H0 tension. A 🧵.
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So excited- I commissioned this! NGC 4258 is arguably most important galaxy for measuring H0, due to being anchor galaxy with megamaser distance. Our group of @DukePhysics tea drinkers (@BrunoSanchez63, @MariaVincenzi7, @erikpeterson23 e.a.) will love this - thx @amyraehill!
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Two new H0 papers on the arXiv last night (one of which I led 😃 ). In short, the H0 tires keep getting kicked, but car is rolling along. A thread.
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Beautiful result led by Adam Riess on one of top questions on accuracy of local H0 measurement - is cepheid photometry right given stellar crowding? Paper shows data matches direct prediction of change in light-curve amplitudes due to crowding precisely. arxiv.org/abs/2005.02445
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Really proud of the @theDESurvey supernova group with a second batch of papers including full data release (former @DukePhysics postdoc @BrunoSanchez63 et al.), new studies on weak lensing of supernovae (Shah et al.), an inverse distance ladder measurement (Camilleri, @tamarastro et al.), a time dilation measurement (White et al.) and dust around supernovae (led by former Duke grad student Brodie Popovic). Just giving arxiv link to data release - arxiv.org/abs/2406.05046, rest of papers on arxiv with 'The Dark Energy Survey Supernova Program:' in title.
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A fourth anchor for H0! 🤯 Great work by Louise Breuval, with data in paper, of new H0 Cepheid cross check (74.1±2.1). And yeah, I’m aware of a recent CCHP talk, my suggestion is to wait until there is a paper with data out. With the number of published cross checks (e.g specifically JWST versus HST) and now Louise’s, need to break something badly to get a lower local H0. arxiv.org/abs/2404.08038
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New week, new H0 tension check-up: arxiv.org/abs/1910.04694 From SH0ES cepheid experts: Unfortunately they used ground-based mags not on HST cal and a third of sample are overtones (different PL relation). With HST cal, no overtones, their H0~73.2
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In Rome at Sapienza University seeing @alemelk and others. Got to take a picture in the Pantheon this morning and now talking about Pantheon+!
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Really cool first H0-related result with JWST led by Wenlong Yuan (arxiv.org/abs/2209.09101). JWST with better resolution than HST can test for crowding, claimed to be a potential H0 systematic. Can see here fantastic agreement in intercept of PL relation between two telescopes.
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This is such fantastic news, I’m thrilled @NikoSarcevic is joining the @DukePhysics cosmology group. See you in the group meetings Niko!
Ok so, cannot hide it any longer: peeps, I am B E Y O N D thrilled to tell you that this fall I’ll be joining @DukeU to work with @michaeltroxel , @KJArunKJ (and other fine folk there). I will continue my work in @LSSTDESC and I will be joining @NASARoman! 🤩
I am so happy 🥳
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In Corfu, Greece for ‘Tensions in Cosmology’ meeting organized by @EleonoraDiVal and others. Got to speak along with @licia_verde and @jcolinhill this morning. Hard to be tense in this place 😀
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The second question: “Could HST Cepheid measurements be non-linear, i.e., change with distance?”. This one is my favorite plot of paper - and is a resounding no. This is first time all the distance measurements have been compared to check linearity (or offset) and find linearity of 0.994+-0.01, non-linearity that would explain Hubble tension ruled out at 7 sigma level. Thats bigger than the Tension itself!
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New Megamaser result out! arxiv.org/abs/2001.09213 - this is a single step distance ladder and we get H0=73.9±3.0 km s−1 Mpc−1 using CMB redshifts. Here, the group improved estimates for 4 galaxies to make sample 6.
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It always feels like there are so many giant telescopes out there, but then a #LIGO NSBH event happens and one needs to cover 20 square deg to 23rd mag when the moon’s out, and you realize how few telescopes can do that ...
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Unbelievably proud of my colleague, next-door office mate, and friend Prof. @michaeltroxel for receiving a DOE Early Career Award! It is so well-deserved. Last passage of press release here - melts me.🔭❣️trinity.duke.edu/exploring-m… @DukeU @DukePhysics @DukeTrinity @chris_w_walter
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Congrats to @DukePhysics new Dr. Brodie Popovic, the first grad student I worked with, for defending his thesis today! [So yeah, I may have hired a facepaint artist I met yesterday at a kids birthday party to draw up Brodie-themed artwork in celebration.]
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Having lived through this Hubble tension stuff for some time, I’d say this is the most solid ground these measurements have ever been on. Please ask any questions!
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Very interesting paper by @desisurvey on a Peculiar Velocity Survey with Fundamental Plane and Tully Fisher relation - they get "H0=76.05±0.35(statistical) ±0.49(systematic FP) ±4.86(statistical due to calibration)": arxiv.org/abs/2408.13842. Couple thoughts -
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Can I propose this week's @KITP_UCSB workshop 'Tensions between the Early and the Late Universe' have a Twitter name #KITP_H0tTakes ? I think this week will have a lot of H0tTakes. @LloydEKnox @AddisonGraeme @ProfMacri - open to suggestions/confirmation.
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So happy about this paper. It started with @DillonBrout sending plots and me saying 'seems cool, but what's the story?' and evolved into him sending more plots and me responding mostly with 'OMG!'s and emojis.
Really excited to share mine and @DScol’s newest paper "It's Dust: Solving the Mysteries of the Intrinsic Scatter and Host-Galaxy Dependence of Standardized Type Ia Supernova Brightnesses" arxiv.org/abs/2004.10206 @astrobites @drbecky_ Our alternate title was...
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"..deviates by more than 3σ from latest Planck CMB measurement. Our results favour values of growth index γ>6/11 or Hubble constant H0>70 or a fluctuation amplitude σ8<0.8 or some combination of these. " Totally different probe, same tensions: just bizarre luck?
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New TRGB H0 paper out led by Sean Li. Biggest sample of SN hosts to date calibrated by TRGB measurements, N=35, and is complete of all available with JWST or HST. Together with the Pantheon+ SN catalog gives H_0=72.1-73.3+-1.8 km/s/Mpc, depending on methodology, in good agreement with the value of 72.5+1.5 using Cepheids in hosts of 42 SNe~Ia calibrated by the same anchor, NGC 4258. arxiv.org/abs/2504.08921
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With talk of HST instruments getting shut down, and recent discussion about local distance ladder with JWST, I wanted to do a little thread about what’s better between HST and JWST for distance ladder measurements. You may be surprised. 🧵
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New paper tonight about TRGB as a distance ladder measurement (arxiv.org/abs/2211.06354). We tried to create a 'unsupervised, standardized approach' to this probe using a great @NASAHubble dataset: GHOSTS. Paper led by undergrad Jiaxi Wu! and with @rareflwr41 @styrofoamplates.
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Very interesting analysis of the first lensed Type Ia supernova that can be used to measure the Hubble constant: SN H0pe arxiv.org/abs/2403.18902 . Because it's a SN Ia, one can leverage the absolute magnification and spectroscopic age-dating (1/3).
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Really enjoyed this interview with @starstrickenSF on #NPRShortWave about dark energy. The story of dark energy is so interesting, and definitely not over.
SO thrilled (and frankly kind of starstruck) to be on @NPR talking about dark energy & the fate of the Universe
i used to listen to Star Date on NPR every day as a little kid, learning about the cosmos. absolutely surreal to be a guest now. #NPRShortWave
npr.org/2020/05/04/850006074…
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New important JWST crosscheck of distance ladder / Hubble tension led by Sean Li, @styrofoamplates et al. New TRGB measurements with JWST in 7 hosts of 9 SN Ia and compares them to same from Cepheid measurements from HST. Very consistent - difference: 0.01+/-0.04 (stat) +/-0.04 (sys) mag (left plot). arxiv.org/abs/2408.00065 🧵
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Huge work here. Was such a pleasure working with @DillonBrout and the Pantheon+ (and SH0ES) team. Great thread by Dillon here. w looks like -1, H0 is still in serious tension, but there's also a ton of new and wonky stuff in this paper. Really proud.
Today was a big one! The culmination of a big push of 10 papers and 3 years of work. Here are the Pantheon+ cosmological constraints for Dark Energy, Dark Matter, and the Hubble constant from Type Ia Supernovae collected over last 2+ decades. Paper: arxiv.org/abs/2202.04077
(1/8)
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Need to digest. Would be easier if I hadn't spent last year arguing from SNe Ia that dust in other galaxies is really different compared to Milky Way / LMC. This paper applies that claim to cepheids. Will try to have some thoughts for my talk tomorrow indico.in2p3.fr/event/19568/…
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Tonight on arxiv, two papers on TRGB measurements of omega centauri, both using Gaia, one by Adam Riess and co. (arxiv.org/abs/2012.09196), one by Wendy Freedman and co.(arxiv.org/abs/2012.09701), that seem to have very different answers. What's going on? Here's a long fun thread
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Excited and proud to share new result led by @astrodarcy and SH0ES/Pantheon+ teams: arxiv.org/abs/2204.10866 "Measurements of the Hubble Constant with a Two Rung Distance Ladder: Two Out of Three Ain't Bad". A 🧵.
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The first main question is “Do other techniques/instruments/teams JWST galaxy distances agree with past HST measurements?” It’s a resounding yes! 👏 All the offsets are on the 0.03 mag level and 1sigma from HST SH0ES, much smaller than Hubble tension scale of 0.18 mag. Conclusion, Hubble Tension is not a distance measuring problem.
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This is pretty amazing. The HST and JWST data are telling a consistent story, just that early JWST samples are too small to measure H0 well. I think that story got a little muddled by latest CCHP paper because some uncertainties were getting removed when they shouldn’t have been, but the important thing to me is that the actual measurements agree between telescopes & teams & methods.
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So either we are left with a super-neat (to me) dust-astrophysics discovery and still tension. Or a puzzling stellar astrophysics discovery with no tension. Or just tension.🤪
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[2201.08997] Leandros Perivolaropoulos: Is the Hubble crisis connected with the extinction of dinosaurs? arxiv.org/abs/2201.08997 arxiv.org/pdf/2201.08997.pdf #astro_ph_EP
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The odds of this discrepancy being due to chance are less than 1 in 100,000. The reported value of H0 is 74.03±1.42 km/s/Mpc. The submitted version of the paper (by Riess, Casertano, Yuan, Macri & Scolnic) can be found here: arxiv.org/abs/1903.07603
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Great result - solidly low H0 for every CMB early universe measurement.
New SPT-3G result! From CMB polarization alone we reconstruct the CMB lensing and an unlensed E-mode power spectrum. We find H0 = 66.8 ± 0.8 km/s/Mpc, in 5.4-sig tension w/ SH0ES, and mnu <0.075eV (95% CL), w/ weak (<3-sig) preference of excess lensing. arxiv.org/abs/2411.06000
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Taught my first classes as a professor this week. I have not yet figured out how professors don't immediately nap right after class.
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Amazing work by NASA and @DukePhysics's @michaeltroxel on the OpenUniverse simulations. We are using these to get ready for @NASARoman! Check out the movies in here! nasa.gov/universe/new-simula…
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So happy for @DukePhysics @DukeTrinity grad student Maria Acevedo for winning an @NSF GRFP fellowship! She is a total boss and is leading an observation program to understand the motions of our neighboring galaxies to better measure the expansion rate of the universe. 🤩🤩
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@theDESurvey just released its first measurements of dark energy using Type Ia Supernovae (SNIa). This came out in 8 papers, so here is an 8-tweet summary of them:
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And here it is, for first time in this H0 saga, the vaunted 5sigma line has been breached. Wow. Amazing what H0LICOW has done - they have quads+doubles, long+short delays, HST+AO, multiple modeling codes ...a great number of crosschecks: arxiv.org/abs/1907.04869
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So proud of @DukePhysics postdoc superstar @MariaVincenzi7 for winning an NASA Einstein Fellowship! So happy we get to spend a little more time with her at Duke before she is off building her own group 🤩
Thrilled and grateful to be part of this! Can't wait to dive deeper into the mysteries of our Universe using all the amazing upcoming SNe Ia experiments 🌟🎆🌌. Looking forward to what is yet to come @DukePhysics !
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Pretty surreal reading this accurate and detailed recap by @nattyover . What I appreciate most about it is that it captures how while we stress and argue over these small systematics, there's also a real sense of joy to be working on this.
I embedded with top cosmologists at a recent meeting in Santa Barbara, where they declared themselves “in crisis.” The universe appears to be expanding too fast — faster than their standard theory predicts. It could be the break they’ve long hoped for. quantamagazine.org/cosmologi…
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So excited about this. It’s really happening. Taking the fam to Florida for this no question 🤟
NASA has selected Falcon Heavy to launch the Roman Space Telescope, which is designed to study dark energy and dark matter, search for and image exoplanets, and more. Liftoff is targeted for no earlier than October 2026 from Launch Complex 39A in Florida nasa.gov/press-release/nasa-…
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New Pantheon+ paper led by grad student Anthony Carr, with famous advisor @tamarastro, and including myself, @Astro_KhaleD, @DillonBrout, @erikpeterson23 - arxiv.org/abs/2112.01471 - this paper does a super comprehensive review of redshifts of all the SNeIa used for cosmology.
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Thanks to @astrocaits and her program looking at Dust in Nearby SNIa Hosts, I got to fly on @SOFIAtelescope the last two nights. It was amazing! Here's a thread (pic here of SOFIA taken sunrise after second night).
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If one combines all the JWST measurements from all the teams, and propagates the covariance and uncertainties correctly, you get the "reversion to the mean" of larger samples: H0=72.6+-2.0 km/s/Mpc from JWST. HST would have predicted H0=72.8 for the same sample, so again JWST and HST agree.
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Group lunch!
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I saw a talk two weeks ago by Sherry Suyu - their strong lens work is super cool and increasingly robust. Either there is some grand systematic conspiracy between the lens team and us local distance ladder folk, or this tension has hit beyond ‘tension’ level🌋
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So happy for @DukePhysics grad student Brodie Popovic's first paper - arxiv.org/abs/1910.05228 and for suffering through with the 'spa meditation' music I played during our editing sessions (to keep the vibes right).
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