Robert Fisher

Well-deserved congratulations!!

GitHub - rtfisher/torque-free-rigid-rotation: Python simulator for torque-free rigid body rotation with dual-frame visualization Python simulator for torque-free rigid body rotation with dual-frame visualization - rtfisher/torque-free-rigid-rotation

This was done with @anthropic.com's Claude Code. You can grab the code yourself here: github.com/rtfisher/tor... .

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."

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!

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...

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-...

Definitely one way to run out of Gauss.

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...

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

[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

📣📣 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? 🧵

Application of THOR raytracing and Lyman-alpha MCRT for a highly-resolve, high redshift galaxy formation simulation at z = 6.

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

Definitely a huge challenge but I know we will eventually get there. It's something I also confronted when teaching math methods; software systems have been better at doing integrals than introductory students for decades, but that doesn't mean we have stopped teaching calculus.

They are extremely useful for many tasks -- from generating comments to code or git commits to developing perfectly formatted figures. But they are improving so rapidly we cannot really ignore them. A new generation of agentic tools like Claude Code are already here.

Sample output from the Claude Code beta command line for the Flash astrophysical hydrodynamics code.

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.

Original Grace under Pressure album.

¡Todavía tengo el vinilo original!

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

Really cool opportunity for advanced grad students and postdocs to learn about and discuss multi-messenger astrophysics in beautiful Santa Cruz! (featuring yours truly)

Hope the historic Orrery made the cut!

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.

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... 🔭🧪

Habitable This is Habitable, a fun deck-building game where players try to find planets, make them habitable, keep them habitable, and make life flourish. We are an international team of astrophysicists

This looks cool!! The postdocs and students at @hitsters.bsky.social developed a Habitable board game last year while I was there. There was a limited run of physical copies, but there is a version available online for free. tabletopia.com/games/habita...

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.

When I was a teaching assistant for Alex Filippenko’s large introductory astronomy course, Alex solicited us (the TAs) for exam questions. The end product was some combination of the best questions from both Alex and the TAs.

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.

Kramers and Holst (1923) captures the brief "old quantum mechanics" of Bohr and Sommerfeld in beautiful illustrations. archive.org/details/atom... Ht/Paul Prudence

Pre-tenure: ~ 1 course per semester. Post-tenure: ~ 1 course / 5 years.

I usually do this as a homework assignment, but it could work in-class: given stellar data, “discover” the HR diagram by plotting mags and then abs mags versus colors. Also interactively see the difference between a magnitude and volume limited sample.

Indeed, we had a preview of what a sudden endowment shortfall looks like — Harvard for instance couldn’t even afford to put breakfast on the table for their students. That is precisely their goal here.

Very cool, thanks!

Is this a Seestar?

There's actually quite a literature surrounding hypothetical "neutrino balls," going back at least to Holdom, 1987 (journals.aps.org/prd/abstract...).

Dan Scolnic posted about it on the other side. x.com/dscol/status...

GitHub - rtfisher/snid_docker Contribute to rtfisher/snid_docker development by creating an account on GitHub.

OS/X (both Intel and silicon) is currently supported, but only minor tweaks will be needed for Windows. github.com/rtfisher/sni...

The requisite legacy PGPLOT library is automatically downloaded and installed with X-Windows interface support. The container hosts the X11 server which the user can easily connect to via a local X11 client on their desktop. The best part is this is all accomplished by running a single script.

A screenshot of SNID-Docker running on OS/X.

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)