iiinova — where your digital self keeps evolving

Andrew J. Steinmetz @ajsteinmetz.com · 01/10/2026

For one reason or another, I stumbled upon this book and I'm happy that it exists. They really make a CRC Handbook for everything. doi.org/10.1201/9781... #Birds #Science

CRC Handbook of Avian Body Masses screenshot.

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Andrew J. Steinmetz @ajsteinmetz.com · 26/09/2026

My thanks to the #GeorgiaTech Montgomery Machine Mall (www.me.gatech.edu/montgomery-m...) for giving a tour to new #GT1000 #Physics students and showing them all the equipment (mills, lathes, CNC machines, etc) that they could be trained on to build and design for projects and experiments. #EduSky

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Andrew J. Steinmetz @ajsteinmetz.com · 13/09/2026

I had fun at the Provost's Welcome Dinner for New Faculty with my wife Sandy at #GeorgiaTech last Wednesday. Met a lot of new faculty and acquaintances. #Atlanta

Portrait of two people in front of Georgia Tech wallpaper.

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Andrew J. Steinmetz @ajsteinmetz.com · 03/09/2026

New #arXiv preprint! I very much enjoyed making some of the figures for this paper about different #nuclear #fusion processes. Here's the CNO "bicycle", responsible for ~2% of solar energy, with branching at solar core temperatures. #Science #AcademicSky #Physics #Astronomy arxiv.org/abs/2609.01366

The carbon-nitrogen-oxygen (CNO) “bicycle,” showing the catalytic hydrogen-burning cycles CNO-I (yellow) and CNO-II (green).

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Andrew J. Steinmetz @ajsteinmetz.com · 02/07/2026

I love Pochettino and #USMNT #USA That was a tough game and they did it. Congratulations! #WorldCup (VAR can suck it)

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Andrew J. Steinmetz @ajsteinmetz.com · 11/06/2026

I had a wonderful time today at the GT 1000 & GT 2000 Instructor Development Conference. Thank you #GeorgiaTech OUESS. I'm looking forward to teaching #GT1000 this upcoming Fall.

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Andrew J. Steinmetz @ajsteinmetz.com · 08/05/2026

@hankgreen.bsky.social Hey Hank, I just watched your video. Yes, #Artemis II was capturing the reflected #Moon e.g. a "moon glint" in the ocean. Check out the analogous "sun glint" reflections captured by #DSCOVR epic.gsfc.nasa.gov/galleries/20... #Science #NASA #Space

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Andrew J. Steinmetz @ajsteinmetz.com · 08/05/2026

It occurs to me that having everything centralized on the cloud might has some downsides. #EduSky #AcademicSky 🙃

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Andrew J. Steinmetz @ajsteinmetz.com · 30/04/2026

This is not an expanding supernova, but a "light echo" as light (from V838 Monocerotis) travels through an already present nebula illuminating it over several years. #Science #Space #Astronomy See: en.wikipedia.org/wiki/V838_Mo... This is similar to the #MIT light-camera: youtu.be/EtsXgODHMWk?...

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Andrew J. Steinmetz @ajsteinmetz.com · 27/04/2026

Dead trees remind me of whale-fall, but for forests, as these collapsed titans (pic: fallen White Oak) decompose into soil/humus which sustains future generations of plant and animal life. #Biology #Science #Ecology

Underside of fall oak tree in the forest.

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Andrew J. Steinmetz @ajsteinmetz.com · 11/04/2026

I always get misty eyed watching the splashdown scene in Apollo 13 and seeing the real thing did the same thing... I just got something in my eye, okay? ❤️ Welcome home #Artemis II! #NASA #Science #Space

The parachutes of the integrity space module are deployed.

Splashdown of the integrity space module.

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Andrew J. Steinmetz @ajsteinmetz.com · 09/04/2026

Lovely pic of myself and onlookers as we view the Orion Nebula during the #GeorgiaTech April 2 Public Night. We also got a nice pic of the #Moon which is fitting given #NASA #Artemis II's journey. Thanks to GT #Astronomy Club! #Science #Physics #Atlanta Credit: www.flickr.com/photos/gtsci...

A crowd gathers to look through a computer screen connected to a small telescope pointed at the stars.

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Andrew J. Steinmetz @ajsteinmetz.com · 21/03/2026

Getting into wearing nicer #Shoes for daily life. Here's my Allen Edmonds Park Avenue Toe Cap Oxfords after a buffing using #Saphir Renovateur and a light coating of black shoe polish.

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Andrew J. Steinmetz @ajsteinmetz.com · 10/03/2026

Heng Yang, a M.S. student in Mechanical Engineering and Applied Mechanics at #UPenn came to #Atlanta to visit #GeorgiaTech and his old physics instructor, yours truly, from when we were both at the #UniversityOfArizona. We got coffee, checked out the campus, and visited #Einstein.

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Andrew J. Steinmetz @ajsteinmetz.com · 19/01/2026

Got married to my now wonderful Wife Sandy!

Two newlyweds stand on the steps in front of a church.

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Andrew J. Steinmetz @ajsteinmetz.com · 29/12/2025

There's a famous Feynman interview where he explains why ice is slippery. It turns out there's more to the story involving shear-stress and slippage of disordered ice layers. Things we experience every day still generate novel thought and research. #Science #Physics journals.aps.org/prl/abstract...

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Andrew J. Steinmetz @ajsteinmetz.com · 06/12/2025

We got to the final listed track, track 15 "The Fate of Thomas Light" and it's the saddest bit of music I've listened to in awhile. Everybody in the Bandcamp livestream was devastated. This can't be the end of Act III. #Protomen #Music #RockOpera

illustration by John DeLucca and design by Caspar Newbolt

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Andrew J. Steinmetz @ajsteinmetz.com · 02/12/2025

We're almost to the end of Act III. It's been a wonderful journey. #Music #RockOpera #Protomen

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Andrew J. Steinmetz @ajsteinmetz.com · 21/11/2025

I love #Quasars! This is 3C 273, brightest in the sky, by #HST #Hubble, 2.5 billion light-years away. The bottom blocks out the supermassive #BlackHole showing more detail. The "L" is a jet, possibly from a disrupted dwarf galaxy. #Science #Astronomy #Space. See: esahubble.org/images/opo24...

A Hubble Space Telescope image of the core of quasar 3C 273. A coronagraph on Hubble blocks out the glare coming from the supermassive black hole at the heart of the quasar. This allows astronomers to see unprecedented details near the black hole such as weird filaments, lobes, and a mysterious L-shaped structure, probably caused by small galaxies being devoured by the black hole. Located 2.5 billion light-years away, 3C 273 is the first quasar (quasi-stellar object) ever discovered, in 1963. NASA, ESA, Bin Ren (Université Côte d’Azur/CNRS) John Bahcall (IAS)

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Andrew J. Steinmetz @ajsteinmetz.com · 21/11/2025

This week's Act III #Protomen is "The Dream." Amazing call back to Act III and it's cool to hear Emily again in the story, even only as a memory. #Music #ConceptAlbum #RockOpera. We're getting to the endgame now.

John DeLucca on illustration and Caspar Newbolt on design.

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Andrew J. Steinmetz @ajsteinmetz.com · 21/11/2025

I missed last week's #Protomen Act III drop. Last week was “The Redline” + “A Show Of Force” #Music #ConceptAlbum #RockOpera

Art by John DeLucca and design by Caspar Newbolt.

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Andrew J. Steinmetz @ajsteinmetz.com · 18/11/2025

This is a gorgeous photo of SN 1987A taken by the Hubble. #NASA #Space #Science #Astronomy #Physics Source: en.wikipedia.org/wiki/File:Su...

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Andrew J. Steinmetz @ajsteinmetz.com · 04/11/2025

New #Protomen! I'm so thrilled to post each and every drop until #ActIII is fully out. theprotomen.bandcamp.com/track/hold-o...

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Andrew J. Steinmetz @ajsteinmetz.com · 31/10/2025

It turns out you can order free hard copies of the NRL Plasma Formulary book from the US Navy. www.nrl.navy.mil/News-Media/P... The PDF is also freely available. Making my tax dollars work lol. Though with the shutdown, I don't know if they'll respond. #Physics #Science 🧪⚛️

Cover of the 2023 Plasma Formulary book by the Naval Research Laboratory.

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Andrew J. Steinmetz @ajsteinmetz.com · 29/10/2025

#TIL the mathematician #Fibonacci (b. 1170) was one of the early promoters of the Indo-Arabic numeral system in Europe in his 13th century book Liber Abaci where he also printed the now famous Fibonacci sequence 1, 2, 3, 5, 8, 13, ... as a solution to the "rabbit problem." #Science #MathSky 🧪🧮

A page of Fibonacci's Liber Abaci from the Biblioteca Nazionale di Firenze showing (in box on right) 13 entries of the Fibonacci sequence.

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Andrew J. Steinmetz @ajsteinmetz.com · 29/10/2025

This City Made Us! #Protomen #Music #RockOpera Act III drops continue with this rerelease of the 2015 EP song. theprotomen.bandcamp.com/track/this-c...

Poster for "This City Made Us" by the Protomen. Art depicts someone walking towards the viewer in books while a figure on a coat walks away. A helmet lies between them.

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Andrew J. Steinmetz @ajsteinmetz.com · 25/10/2025

Now here's an example of one of the more useful applications of #AI and #MachineLearning within #Medicine. AI-assisted doctors are significantly better at detecting breast cancers in women. This kind of usage directly saves people's lives. #Science #MedSky 🧪💊 Source: doi.org/10.1038/s415...

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Andrew J. Steinmetz @ajsteinmetz.com · 25/10/2025

I recently gave a presentation on #AI which covered in-part the dangers of over-reliance in #Medicine. While lots of attention is on #Education, with good reason, even experts are at risk of "deskilling." #AcademicSky #Science #MedSky 🧪💊 Source: doi.org/10.1016/s246...

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Andrew J. Steinmetz @ajsteinmetz.com · 23/10/2025

I won't stop #Protomen posting until Act III is fully out and dropped. Calling Out is a great song. #Music #RockOpera youtu.be/z2Wh3hq2EPQ?...

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Andrew J. Steinmetz @ajsteinmetz.com · 14/10/2025

More Act III posting. Today's juice is The Storm and Buried in the Red! Continue the new songs #Protomen! #Music #RockOpera #ConceptAlbum.

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Andrew J. Steinmetz @ajsteinmetz.com · 08/10/2025

Second week of new songs for the #Protomen final album Act III: This City Made Us. I've waited like 16 years for this! No Way Back is an absolute banger. #Music #RockOpera #Rock theprotomen.bandcamp.com/album/act-ii...

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Andrew J. Steinmetz @ajsteinmetz.com · 22/09/2025

This is my favorite #Jazz album and my first #Japanese #CD. Flying Beagle, 1987, is by Himiko Kikuchi. The dog's name is Boogie and is absolutely the reason I originally listened to this.

2024 CD reissue of 1987's Flying Beagle album by Himiko Kikuchi.

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Andrew J. Steinmetz @ajsteinmetz.com · 20/09/2025

Hmm. 🤔 Enrollment in bachelor's degrees in #Physics seems to have fallen off a cliff in German universities since the pandemic. Anybody know if this trend has reproduced itself in your country or in another STEM field? #EduSky #AcademicSky #Science 🧪⚛️ Source: www.dpg-physik.de/veroeffentli...

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Andrew J. Steinmetz @ajsteinmetz.com · 17/09/2025

TIL that popcorn is an ancient snack with evidence going back to 4,700 BC in Peru via radiocarbon dating. That's potentially older than the potter's wheel! #Science #Archeology #History 🧪 Source: doi.org/10.1073/pnas...

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Andrew J. Steinmetz @ajsteinmetz.com · 16/09/2025

Oppenheimer-Snyder collapse (Penrose coordinates) shows how #BlackHoles form with radius (x-axis) & time (y). The star's surface (white) becomes the "antihorizon" of the BH (upper half diamond) with a singularity (cyan). #Physics #Astronomy #Science 🧪🔭⚛️ More info: jila.colorado.edu/~ajsh/bh/col...

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Andrew J. Steinmetz @ajsteinmetz.com · 21/07/2025

#Crocodilian snout bumps = integumentary sensory organs (ISOs). With 4,000 (American alligators) - 9,000 (Nile crocodiles), each is a dome of touch cells that fire at just 0.08 mN or more sensitive than our fingertips! #Science #HerpSky #Biology See: Leitch & Catania 2012 doi.org/10.1242/jeb....

Figure 2 from Leitch & Catania 2012. (A) Juvenile alligator head with ISOs highlighted, (B) close‑up scanning‑electron micrograph of a single dome‑shaped ISO, (C) lateral view of the skull showing ISO distribution along the jaws.

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Andrew J. Steinmetz @ajsteinmetz.com · 20/07/2025

I'm digging the #GitHub style post activity, but for my #BlueSky posts. Thanks @blueskymeter.com! :)

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Andrew J. Steinmetz @ajsteinmetz.com · 19/07/2025

The #CMB spectra temperature fluctuations can be broken down using spherical harmonics e.g. monopole + dipole + quadrupole + etc. Like a bumpy potato, the lower order ℓ-multipoles make large-scale bumps; higher order ℓ make tiny bumps. #Science #Physics #Astronomy🧪⚛️🔭 Source: doi.org/10.1086/513698

(Upper) All-sky picture of the infant universe created from nine years of WMAP data. The image reveals 13.77 billion year old temperature fluctuations (shown as color differences) that correspond to the seeds that grew to become the galaxies. (Lower) WMAP 3-year Power spectrum of CMB compared to recent measurements of BOOMERanG , CBI, VSA and ACBAR.

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Andrew J. Steinmetz @ajsteinmetz.com · 17/07/2025

(1/n) Why do we believe in dark matter when we can't directly see it? The distinction between a "direct" and "indirect" is more a spectrum than a binary. Galaxy rotation is fairly indirect and could be explained by something like modified Newtonian dynamics (MOND). #Science #Physics #Astronomy 🧪⚛️🔭🧵

First peak shows the universe is close to spatially flat. Constraints on the second peak indicate substantial amounts of dark baryons. Third peak will measure the physical density of the dark matter. https://background.uchicago.edu/~whu/intermediate/intermediate.html

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Andrew J. Steinmetz @ajsteinmetz.com · 07/07/2025

Uranium ore is mostly U-238 - an isotope with a 4.5-billion-year half-life. The fissile star of the show, U-235, makes up just 0.72% of natural uranium. That tiny fraction? It's what fuels reactors and bombs alike. #Science #Physics #NuclearPhysics #Isotopes Image: en.wikipedia.org/wiki/File:HE...

A billet of highly enriched uranium that was recovered from scrap processed at the Y-12 National Security Complex Plant. Source: https://en.wikipedia.org/wiki/File:HEUraniumC.jpg

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Andrew J. Steinmetz @ajsteinmetz.com · 03/07/2025

The #TopQuark decays too fast to hadronize. Its lifetime (~5×10⁻²⁵ s) is shorter than #QCD timescales (~10⁻²⁴ s). So we see a "bare" quark decay: t → W + b, before confinement. A rare clean look into quark physics. 🧪⚛️ #Science #ParticlePhysics #Physics Image: commons.m.wikimedia.org/wiki/File:To...

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Andrew J. Steinmetz @ajsteinmetz.com · 02/07/2025

#TyrannosaurusRex modeled for the American Museum of Natural History @amnh.org, New York in 1913 and 2020. Notice the original incorrect upright position, tail dragging, and three fingers! We've come a long way in understanding dinosaur anatomy. 🧪🦖 #Dinosaurs #PaleoSky #Fossil #Paleontology #Science

Top: This is a scale model of a Tyrannosaurus rex exhibit which was planned by the American Museum of Natural History but never executed. Source: Osborn, H.F. 1913. Tyrannosaurus: restoration and model of the skeleton. Bulletin of the American Museum of Natural History 32: 91-92. https://commons.m.wikimedia.org/wiki/File:AMNH_rex_mount.png

Bottom: More anatomically accurate modern arrangement AMNH 5027 with corrected skeleton and horizontal body plan. Source: https://commons.m.wikimedia.org/wiki/File:AMNH_5027_Trex.jpg

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Andrew J. Steinmetz @ajsteinmetz.com · 01/07/2025

I found this utterly charming #Drawing of acanthodians from the Early Devonian (aka early jawed fishes) which were precursors to modern cartilaginous fish and #Sharks. #Evolution #Biology #Science #PaleoSky 🧪🧬🦈 Image Credit: Stanton F. Fink commons.wikimedia.org/wiki/File:Me...

A drawing of three ancient jawed fishes from the Early Devonian swimming in the ocean. The have several spiny fins and large black eyes.

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Andrew J. Steinmetz @ajsteinmetz.com · 15/06/2025

Having a wonderful evening with my coworkers and friends in downtown #Tianjin #China on the river. The cityscape is very pretty at night!

Cityscape of downtown Tianjin on the river.

A group of people stand on a bridge over a river showing the nightscape of downtown Tianjin.

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