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Robert Fisher

@fisherastro.bsky.social
526 followers 408 following 81 posts

Caltech-UC Berkeley-LLNL-Chicago-UMass Dartmouth. Sabbatical 23-24 @ Institute for Advanced Studies and Heidelberg Institute for Theoretical Studies. American & Italian Theoretical and Computational Astrophysicist. Professor. He/him/his.

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Robert Fisher @fisherastro.bsky.social · 03/11/2025
I have been experimenting with large language models to "collaboratively" write code to illustrate key physical concepts for my junior-level mechanics class for physics majors. It did a very nice job in generating an animation of the "tennis racket theorem."
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Robert Fisher @fisherastro.bsky.social · 28/10/2025
We're hiring a teaching physics professor! Our campus feels like a liberal arts sized college within a research university. Our current teaching faculty teach first year to graduate level courses and mentor undergraduate and graduate research students. careers.umassd.edu/en-us/job/52...
careers.umassd.edu
Details - Assistant/Associate Teaching Professor - Physics
Discover exciting career opportunities at UMass Dartmouth. Join our diverse team and make a difference. Explore job openings now at UMassD!
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Philip Mocz @philipmocz.bsky.social · 14/09/2025
I noticed Google search is no longer reliable for quick unit conversions & calculations. So I built a simple online calculator Give it a spin: pmocz.github.io/online-unit-...
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Robert Fisher @fisherastro.bsky.social · 18/08/2025
Generative AI is rapidly progressing and threatens to inundate us. A new paper (including my old Caltech classmate Serge Belognie) utilizes noise-encoded illumination to “watermark” live video. It offers some hope for those concerned for team reality. arxiv.org/abs/2507.23002 h/t @truesciphi.org
arxiv.org
Noise-Coded Illumination for Forensic and Photometric Video Analysis
The proliferation of advanced tools for manipulating video has led to an arms race, pitting those who wish to sow disinformation against those who want to detect and expose it. Unfortunately, time fav...
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Chanda Prescod-Weinstein 🌌 @chanda.blacksky.app · 28/07/2025
📣📣 BOOK NEWS 📣📣 I'm excited to share the cover and release date of Book #2, #EdgeOfSpaceTime, which is now available for PREORDER!! You can order from ANY bookstore, including your local indie! More details on preordering here: www.penguinrandomhouse.com/books/746817... What's the book about? 🧵
[neon rainbow pattern background]
THE EDGE OF SPACE-TIME

The universe reimagined -- through pop culture, poetry, and theoretical physics.

From the award-winning author of The Disordered Cosmos

image of the cover of the book which features circular artwork in the center, one half of it a black and white pattern and the other half a neon rainbow pattern

PREORDER NOW Coming 4/7/26 
image of the Pantheon logo
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Robert Fisher @fisherastro.bsky.social · 27/07/2025
It's always great to see the successes of former students. Postdoc Chris Byrohl @cbyrohl.bsky.social, whom I've known he was an undergraduate, published an amazing paper this week on his new GPU accelerated Ly-α radiative transfer code THOR Hugely impressive results! arxiv.org/abs/2507.11603
Application of THOR raytracing and Lyman-alpha MCRT for a highly-resolve, high redshift galaxy formation simulation at z = 6.
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Robert Fisher @fisherastro.bsky.social · 04/05/2025
Experimenting with the @anthropic.com Claude Code command line beta. In some ways, it is a natural extension of the familiar chat LLM interface. In others, it offers a brief glimpse of more agentic AIs to come -- building and running code and analyzing results largely on its own.
Sample output from the Claude Code beta command line for the Flash astrophysical hydrodynamics code.
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sanjana! @sanjanacurtis.bsky.social · 15/04/2025
Really cool opportunity for advanced grad students and postdocs to learn about and discuss multi-messenger astrophysics in beautiful Santa Cruz! (featuring yours truly)
4th Santa Cruz School on Multi-Messenger
Astrophysics, July 11-20, 2025

Sponsored by the NSF Physics Frontier Center N3AS

Intended for advanced graduate students and beginning postdoctoral researchers interested in nuclear and particle astrophysics - theory, experiment, or observation

Apply Online N3AS.berkeley.edu/summer2025

Application Deadline June 6, 2025

Support available to cover participants' local costs

Speakers include:
John Beacom (Ohio State)
Astrophysical Neutrinos: Sources and Detection
Sanjana Curtis (Oregon State)
The Origin of Milky Way Elements
Rahul Kannan (York University)
Simulating the First Billion Years of Cosmic Time
Dan Kasen (UC Berkeley)
Mergers and Kilonovae, and what they tell us about Nucleosynthesis
Spencer Klein (Lawrence Berkeley Lab)|
IceCube and Beyond: Ultra-High Energy Neutrinos
Rocky Kolb (U Chicago) |
The Standard Cosmological Model
Adrian Lee (UC Berkeley)
What we have & could learn from the Cosmic Microwave Background
Chung-Pei Ma (UC Berkeley)
Ultra-massive Black Holes and their Gravitational Waves
Dominic Pesce (CFA, Harvard)
Exploring the Universe in Radio Waves
Matt Pyle (UC Berkeley)
Dark Matter Experiment
Sanjay Reddy (U Washington)
Neutron Star Properties; Neutron Stars as Physics Laboratories
Dave Schlegel (Lawrence Berkeley Lab) First Results from the Dark Energy Survey Instrument

Location: University of California, Santa Cruz
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Robert Fisher @fisherastro.bsky.social · 08/04/2025
My research group alumna, Mckenzie Ferrari has made her debut contribution to the astronomy reader's digest Astrobites! In her engaging review, Mckenzie dives into a paper exploring the origins of astronomical candles that shine a bit too brightly. aasnova.org/2025/04/08/s... 🔭🧪
aasnova.org
Shedding Light on Candles That Burn a Bit Too Bright
Astrobites reports on how standard candles might not be quite as standard as previously thought, and how a particular type of supernova is making a name for itself.
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Robert Fisher @fisherastro.bsky.social · 24/03/2025
The ESA Gaia mission mapped out the positions and velocities of over a billion stars in our galaxy and led directly to dozens of breakthrough investigations in stellar astrophysics. Godspeed.
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Robert Fisher @fisherastro.bsky.social · 02/03/2025
Kramers and Holst (1923) captures the brief "old quantum mechanics" of Bohr and Sommerfeld in beautiful illustrations. archive.org/details/atom... Ht/Paul Prudence
Schematic diagram of the outermost Bohr orbitals of sodium, showing elliptical orbitals.A schematic diagram of the Bohr orbitals of radium (atomic number 88), showing the symmetric nature of the full shells of elliptical orbitals.A schematic diagram of the formation of a hydrogen molecule. The diagram shows two hydrogen atoms approaching one another in three stages, finally resulting in the two electrons orbiting one another in a circular orbit, with the protons some distance away to either side.
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Robert Fisher @fisherastro.bsky.social · 23/12/2024
I’ve written a short Docker file to easily enable anyone to run Blondin & Tonry’s SuperNova IDentification (SNID) code on almost any platform. (1/2)
A screenshot of SNID-Docker running on OS/X.
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Dr. Skylar Grayson @skylargrayson.bsky.social · 10/12/2024
Periodic reminder that the sun isn’t going to explode. It will slowly ploof out and completely wreck the inner solar system in ~5 billion years but a ploof is very different from a boom. The sun (as crazy as this seems when you think about how big the sun is) is too small to go supernova
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Robert Fisher @fisherastro.bsky.social · 07/12/2024
So many Weinberg gems in this talk. This one slide distills the essence of his approach to science wonderfully. As someone who interacts primarily through the command line still, I feel for the loss of the “good old days” of MS-DOS. 🙂
A short bullet point list titled “Some of Steve’s distinctive qualities as a researcher” from John Preskill’s talk. One example “Not a visual thinker : He had little use for figures (reluctant migration from MS-DOS to Windows).”
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Nilesh Trivedi @nilesh.trivedi.link · 29/11/2024
floss.fund is offering $1 million per year grant to open-source projects. But very few applications have been received so far, and it needs help spreading the word. Please RT/boost and upvote it on HackerNews: news.ycombinator.com/item?id=4227... #foss #OpenSource #sustainability
floss.fund
Funding for Free and Open Source projects - FLOSS/fund
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Robert Fisher @fisherastro.bsky.social · 01/12/2024
Exciting to see so many new folks here. I’m a computational astrophysicist working to understand how dead cinders of stars can blow up and light up the sky in a last hurrah. We use big computers. (Figure below courtesy of current PhD student Vrutant Mehta and collaborator Ruediger Pakmor.)
Two plots, showing the density and the gradient of the velocity field of merging binary white dwarfs (top and bottom, respectively). Two detonations are seen in the lower, more massive white dwarfs.
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sanjana! @sanjanacurtis.bsky.social · 18/09/2024
Exciting news everyone! I am hiring a postdoc scholar to work with me at Oregon State Physics. If you love computational astrophysics, supernovae, and/or compact object mergers, this may be a great fit for you. More information here: aas.org/jobregister/...
aas.org
Postdoctoral Scholar in Theoretical and Computational Astrophysics | American Astronomical Society
The Department of Physics at Oregon State University invites applications for a 2 year postdoctoral scholar position. The successful candidate will work with Prof. Sanjana Curtis on multi-messenger as...
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Robert Fisher @fisherastro.bsky.social · 07/10/2024
@bot.astronomy.blue signup
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Robert Fisher @fisherastro.bsky.social · 06/10/2024
I participated in the judging of an elevator pitch competition hosted by our campus’s NSBE chapter. Every one of the participants deserves the opportunity to go to the national meeting to advance their career aspirations. Can you help make it happen? www.linkedin.com/posts/maxime...
linkedin.com
Maxime Larsen on LinkedIn: #nsbegold #nsbegold #nsbe
I just got asked a magical question! Why don't you bring every student from NSBE to the National Convention? I know the answer to this valid question but I…
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Robert Fisher @fisherastro.bsky.social · 22/09/2024
The great astro Exodus from X took place early in Bluesky’s development, thanks to @astrokatie.com’s engagement. With X continuing to melt down, these numbers will only grow with time.
A virtual certificate with text "Celebrating 10M users on Bluesky, #83,849, Robert Fisher ‪@fisherastro.bsky.social‬, joined on May 20, 2023"
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Astronomer Royal for Scotland | Catherine Heymans @astroroyalscot.bsky.social · 29/07/2024
A calming happy astro #poem for the start of your week. I'm guessing John Updike wasn't aware of the blaze star though, a white dwarf that is currently busy cannibalising its neighbour, and about to explode, creating hellfire for a whole week! 🧪🔭 😱 ℹ️: www.astronomyedinburgh.org/2024/07/10/t...
White Dwarf

John Updike


   Welcome, welcome little star!
   I'm delighted that you are
   Up in heaven's vast extent
   No bigger than a continent.

   Relatively minuscule
   Spinning like a penny spoon
   Glinting like a polished spoon
   A kind of kindled demi-moon,

   You offer cheer to tiny Man
   'Mid galaxies Gargantuan --
   A little pill in endless night
   An antidote to cosmic fright.
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Robert Fisher @fisherastro.bsky.social · 29/06/2024
My Heidelberg Joint Astronomical Colloquium, “An Emerging Consensus on White Dwarf Supernovae” is now available to view on YouTube. youtu.be/ZlRBn8PAyX8?si… @hitsters.bsky.social @mpi-astro.bsky.social
An image of the old bridge over the Neckar River in Heidelberg, Germany, with the text “Heidelberg Joint Astronomical Colloquium.”
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Robert Fisher @fisherastro.bsky.social · 14/06/2024
Huge congratulations to Logan Cabral-Pelletier and the other recipients on receiving a DOE CSGF fellowship! Logan is the second member or alum of my group to have garnered this highly selective honor, after Gabriel Casabona. www.energy.gov/science/arti...
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Robert Fisher @fisherastro.bsky.social · 14/06/2024
Today marks the 60th anniversary of the ground-breaking ceremony at SMTI, the institution which later joined the University of Massachusetts system as the University of Massachusetts Dartmouth in 1991, bringing a world-class research university to the South Coast of Massachusetts.
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The Open Journal of Astrophysics @ojastro.bsky.social · 29/04/2024
New Publication at the Open Journal of Astrophysics: "Supernovae in 2023 (review): possible breakthroughs by late observations" by Noam Soker (Technion - Israel Institute of Technology, Haifa, Israel) astro.theoj.org/article/1171...
astro.theoj.org
Supernovae in 2023 (review): possible breakthroughs by late observations | Published in The Open Journal of Astrophysics
By Noam Soker. A discussion of observations of the aftermath of supernovae explosions, such as supernova remnants, and how these may shed light on the explosion mechanism
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Robert Fisher @fisherastro.bsky.social · 14/03/2024
On this pi day, give a thought to Ludolph van Ceulen, who spent 25 years calculating pi to 35 digits. Prior to the 18th c., pi was known as the "Ludolphine number." Even in his home town of Delft, van Ceulen is remembered only by a printout in a window.
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Robert Fisher @fisherastro.bsky.social · 20/01/2024
Welcome to the azure heavens!
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Robert Fisher @fisherastro.bsky.social · 16/01/2024
I heard the sad news that Chris Belczynski passed away very prematurely this weekend. He is best known for his population synthesis predictions for LIGO sources. I saw him speak only once in 2016, with a prescient prediction of LIGO’s NS-NS rate. t.co/GZNWr09c0r
t.co
Krzysztof's Memorial
View Krzysztof's Tribute to Share a Memory and Photos.
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Michael Zingale @michaelzingale.bsky.social · 10/01/2024
As the semester starts, remember that using and creating open education resources is a great way to lower costs for students and to collaboratively develop texts for our field. Check out the Open Astrophysics Bookshelf: github.com/Open-Astroph... Raise an issue to add your own stuff #astro
github.com
Open Astrophysics Bookshelf
A collection of open-licensed "living" textbooks on topics in astrophysics - Open Astrophysics Bookshelf
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Robert Fisher @fisherastro.bsky.social · 31/10/2023
Heidelberger Schloss on All Hallow’s Eve. Happy Halloween! 🎃
Heidelberg Castle at night.
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Robert Fisher @fisherastro.bsky.social · 31/10/2023
Wow, amazing to see how LeGuin captured the pivotal moment in the first Earthsea novel in such a seamless fashion. Such a shame that after so much fantasy has found its way to the silver screen, LeGuin has never had a proper interpreter.
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Michael Zingale @michaelzingale.bsky.social · 30/10/2023
interested in computational science for grad school? Apply for one of the Stony Brook Institute for Advanced Science graduate fellowships: iacs.stonybrook.edu/opportunitie... I'm happy to chat with anyone interested in computational astrophysics #astro
iacs.stonybrook.edu
Graduate Fellowships | Institute for Advanced Computational Science
Graduate Fellowship Opportunities
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Robert Fisher @fisherastro.bsky.social · 24/10/2023
Ramesh is an outstanding scientist and also such a down-to-Earth guy. Can’t wait to see this!
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Prof. Carl E. Fields 💥 @carlnotsagan.github.io · 29/09/2023
new paper alert ‼️ have u ever wanted to use the stellar evolution code, MESA, in your class but don’t know where to start or don’t want install it? then you should try MESA-Web! paper online now: arxiv.org/abs/2309.15930 w/ @michaelzingale.bsky.social + more ✨
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Robert Fisher @fisherastro.bsky.social · 28/09/2023
It’s been wonderful spending the first leg of my sabbatical at the Institute of Advanced Studies. I had the opportunity to work with some amazing junior scholars and reconnect with some distinguished senior folks. Nächster Stopp: Deutschland!
Sunset photo of Fuld Hall at IAS.Pond at IAS.Nighttime photo at IAS.The sprawling front lawn of IAS.
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Dan F-M @dfm.io · 20/09/2023
We're hiring postdoc fellowship positions at the Center for Computational Astrophysics! 3 year FRF: apply.interfolio.com/132546 5 year FSRF (focus on software development): apply.interfolio.com/132547 This is a great place to work & these are awesome jobs! Please share & reach out with questions!!
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Robert Fisher @fisherastro.bsky.social · 11/09/2023
“We have learned that no theory of everything can include every interesting thing.” - Leo Kadanoff
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Robert Fisher @fisherastro.bsky.social · 29/08/2023
At one point, physisict Nick Hitchon, admitted to documenterian Michael Apted that he will always be more famous for his appearance in his groundbreaking series "7 Up" than for his work on plasma physics. www.theguardian.com/environment/...
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saurabh w jha @sublunar.bsky.social · 25/08/2023
Supernova 2022pul with an amazing JWST spectrum. Read all about it in papers led by Matt Siebert and Lindsey Kwok and an awesome team of collaborators. And more to come! arxiv.org/abs/2308.12449 arxiv.org/abs/2308.12450
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Robert Fisher @fisherastro.bsky.social · 24/08/2023
The names of our galaxy’s large satellites are quite ahistorical. It’s time we did something about it.
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Dr Ashley J Ruiter @astronomash.bsky.social · 18/08/2023
2nd Announcement: abstract submission deadline for Transients Down Under is in 4 weeks! 🌟 transientsdownunder.github.io #transients #observation #theory #telescope_coordination #follow-up #cultural_astro #data #instrumentation
transientsdownunder.github.io
Transients Down Under
Mon Jan 29 - Fri Feb 2, 2024 @ Swinburne Institute of Technology, Melbourne, Australia. Background image: Vela supernova remnant. Image credit: ESO/VPHAS+ team. Acknowledgement: Cambridge Astronomical...
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Robert Fisher @fisherastro.bsky.social · 18/08/2023
Proud of undergraduate research student Amelia Melhem, who was selected to participate in Caltech’s FUTURE program! Amelia is on a paper coming soon, and will be a great student for one lucky PhD program next year! www.caltech.edu/about/news/helping-…
A screen capture of an email announcing the FUTURE acceptance.
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Robert Fisher @fisherastro.bsky.social · 15/08/2023
My first post in the azure heavens. It seems there is a critical mass of astro and physics folks on this platform, which is nice to see!
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