Prof. Joey "Barely a Footnote" Neilsen
@joeyneilsen.bsky.social
Black hole astrophysicist at Villanova. Formerly: MIT, Boston University, Harvard, Kenyon College | X-rays | husband | dad of 2 | cooking. He/him. Skeets are my own.
Pinned
Wow hi new followers! I’m a physics professor and I study black holes. I’m here to talk about teaching, science, marriage, parenting, cooking, dogs, politics, my crumbling old house. I heart dad jokes. Trans rights are human rights, Black Lives Matter, and I abhor violence.
is there any soup liberals ARE excited about?
chef: who wants dirt soup
everyone: what? no thank you, just regular soup
chef: bad news we had to get rid of the soup to provide the dirt
everyone: but we hate dirt
chef: (mouthful of dirt) who wants dirt
everyone: what? no thank you, just regular soup
chef: bad news we had to get rid of the soup to provide the dirt
everyone: but we hate dirt
chef: (mouthful of dirt) who wants dirt
February 18, 2026 at 6:09 PM
is there any soup liberals ARE excited about?
Reposted by Prof. Joey "Barely a Footnote" Neilsen
Gung Roulé Mubarak
So tomorrow is Mardi Gras *and* lunar new year *and* the beginning of Ramadan?
February 17, 2026 at 4:50 AM
Gung Roulé Mubarak
The other day everyone was like "i don't understand this at all" and I was like "it's obvious, it's just like if darts was bowling on ice and you did it from half a football field away" and then we just watched one match for the entire night
Curling is on in my living room and I don’t know how I got to this place
February 17, 2026 at 4:22 AM
The other day everyone was like "i don't understand this at all" and I was like "it's obvious, it's just like if darts was bowling on ice and you did it from half a football field away" and then we just watched one match for the entire night
final jeopardy except they show you what's behind one of the doors and you have to decide if you're going to change your answer or not
February 13, 2026 at 6:15 AM
final jeopardy except they show you what's behind one of the doors and you have to decide if you're going to change your answer or not
triple axel wobble shouldn't be there
(quad)ruple axel also oughta be there
if your triple axel wobbles
you probly haven't gotta
chance to beat him in the figure skating tournament
(quad)ruple axel also oughta be there
if your triple axel wobbles
you probly haven't gotta
chance to beat him in the figure skating tournament
watching half the skaters fuck up the triple axel and I have no idea how Ilia lands a quadruple axel
February 11, 2026 at 5:17 AM
triple axel wobble shouldn't be there
(quad)ruple axel also oughta be there
if your triple axel wobbles
you probly haven't gotta
chance to beat him in the figure skating tournament
(quad)ruple axel also oughta be there
if your triple axel wobbles
you probly haven't gotta
chance to beat him in the figure skating tournament
The next time someone says this to me, I am asking them if they would watch the OpenAI Bowl.
people who say that all creative endeavor can be replaced with AI probably need to reckon with the fact that all televised sports events with human athletes could easily be replicated by high-definition computer-animated simulations….and yet we don’t do this and no one seems to want to.
February 9, 2026 at 12:04 AM
The next time someone says this to me, I am asking them if they would watch the OpenAI Bowl.
My first aurora changed very slowly, almost imperceptibly, EXCEPT that there was a sudden streak across the sky, like a bolt of distinctly green lightning.
I’ve caught glimpses of a decent aurora once, nowhere near this spectacular, but the thing that struck me most was that the light flowed in a way that was very conspicuously NOT like a liquid but like electricity. It felt like being inside one of those plasma globe lamps. Eerie and breathtaking.
The aurora last night in Beaver, Alaska was just incredible. This is a real-time video (not sped up) of the crazy motion I saw. Also, look how BRIGHT it is, wow!
February 8, 2026 at 3:26 AM
My first aurora changed very slowly, almost imperceptibly, EXCEPT that there was a sudden streak across the sky, like a bolt of distinctly green lightning.
My college math major had a 1st-year course called "Foundations of Abstract Math." Not only was it great fun, it also changed how I thought about arguments and evidence and logic.
In the US, mathematical education typically doesn't include *any proofs*, for anything other than a few months of geometry, up until several years into university.
Typically, an analysis or linear algebra course in like year 2 of uni is the first time US students actually have to prove stuff.
Typically, an analysis or linear algebra course in like year 2 of uni is the first time US students actually have to prove stuff.
February 5, 2026 at 12:27 AM
My college math major had a 1st-year course called "Foundations of Abstract Math." Not only was it great fun, it also changed how I thought about arguments and evidence and logic.
Reposted by Prof. Joey "Barely a Footnote" Neilsen
I have some bad news. One, if you need to use ChatGPT for your graduate application letter, you are not ready for graduate school.
Two, no, not "everyone is doing it" and those who don't do it aren't "losing out." ChatGPT is not an advantage.
Two, no, not "everyone is doing it" and those who don't do it aren't "losing out." ChatGPT is not an advantage.
An impressive number of graduate applications this year used the phrase “curiosity-driven approach” 🤔
January 17, 2026 at 10:46 PM
I have some bad news. One, if you need to use ChatGPT for your graduate application letter, you are not ready for graduate school.
Two, no, not "everyone is doing it" and those who don't do it aren't "losing out." ChatGPT is not an advantage.
Two, no, not "everyone is doing it" and those who don't do it aren't "losing out." ChatGPT is not an advantage.
Reposted by Prof. Joey "Barely a Footnote" Neilsen
Joey is upset because he’s only a footnote in The Edge of Space-Time
Ooh you should take it out on one of your other friends! 🤞
January 13, 2026 at 2:14 AM
Joey is upset because he’s only a footnote in The Edge of Space-Time
Being a grown up is cool. Having to be A Grown Up is exhausting.
January 8, 2026 at 9:00 PM
Being a grown up is cool. Having to be A Grown Up is exhausting.
I was walking my dog behind a guy who was walking two dogs. I kept trying to cross the street so we could get ahead of them, but he kept crossing the street at the same time.
Please quote this with stories of your minor interactions with non-celebrities, e.g. “I once accidentally bumped into a man in the Wellingborough branch of Holland & Barrett”
December 30, 2025 at 3:41 PM
I was walking my dog behind a guy who was walking two dogs. I kept trying to cross the street so we could get ahead of them, but he kept crossing the street at the same time.
Maybe they should have put lox on the truck.
If you're a shipper and you get $400K in lobster stolen, you are ship out of luck.
Will the police move a mussel to find the culprits?
December 30, 2025 at 4:51 AM
Maybe they should have put lox on the truck.
ruin two bands by combining them
alvin and the dixie chipmunks
alvin and the dixie chipmunks
ruin two bands by combining them:
led zeppelinxs
led zeppelinxs
ruin two bands by combining them:
the aerosmiths
the aerosmiths
December 30, 2025 at 3:25 AM
ruin two bands by combining them
alvin and the dixie chipmunks
alvin and the dixie chipmunks
we were almost saved from cars 2. this is why i never back anything up
what's not part of this anecdote is that it happened AGAIN, on cars 2. an intern wrote a cron job to delete his daily code tree, re-sync and rebuild every night. so that like looked like rm -rf /$MY_TREE
unix users following along will see where this is going
unix users following along will see where this is going
December 30, 2025 at 2:42 AM
we were almost saved from cars 2. this is why i never back anything up
1. For actual interaction: John Kerry talked about me in his commencement speech and called me a hero when I walked across the stage.
2. For most minor interaction: I walked past Michael Ian Black at the airport.
3. Most vicarious: my wife (Not On Here) bumped into Patrick Stewart in London.
2. For most minor interaction: I walked past Michael Ian Black at the airport.
3. Most vicarious: my wife (Not On Here) bumped into Patrick Stewart in London.
Right folks. Feeling rather down at the moment so bringing back an oldie
Please Quote this with your most minor celebrity interaction
Please Quote this with your most minor celebrity interaction
December 29, 2025 at 11:17 PM
1. For actual interaction: John Kerry talked about me in his commencement speech and called me a hero when I walked across the stage.
2. For most minor interaction: I walked past Michael Ian Black at the airport.
3. Most vicarious: my wife (Not On Here) bumped into Patrick Stewart in London.
2. For most minor interaction: I walked past Michael Ian Black at the airport.
3. Most vicarious: my wife (Not On Here) bumped into Patrick Stewart in London.
ruin two bands by combining them
rage against the machine gun kelly
rage against the machine gun kelly
ruin two bands by combining them
LL Kool J-Gang
LL Kool J-Gang
ruin two bands by combining them:
Blood, Sweat, and Tears for Fears
Blood, Sweat, and Tears for Fears
December 29, 2025 at 11:06 PM
ruin two bands by combining them
rage against the machine gun kelly
rage against the machine gun kelly
cheesy beef and cheese Kringle send skeet
December 19, 2025 at 6:13 PM
cheesy beef and cheese Kringle send skeet
An implausible plot point in an otherwise highly believable holiday tale
'christmas vacation' has a can-you-believe-this part at the end where cousin eddy kidnaps clark’s boss to demand his bonus, and i wonder if the filmmakers realized that angry mobs threatening rich people to give them gifts and lavish parties at christmas has a robust historical lineage
December 16, 2025 at 8:47 PM
An implausible plot point in an otherwise highly believable holiday tale
it is so much easier to explain "here's a person and here's how to treat them kindly" to a child than it is to explain why anyone would treat them unkindly in the first place.
“How do I explain trans people to my kids”
mate, what are you explaining? “Kids, this is Mr Jay, would you like to wave or fistbump or shake hands?”
what is there to explain beyond “here’s a person”
mate, what are you explaining? “Kids, this is Mr Jay, would you like to wave or fistbump or shake hands?”
what is there to explain beyond “here’s a person”
December 15, 2025 at 1:22 PM
it is so much easier to explain "here's a person and here's how to treat them kindly" to a child than it is to explain why anyone would treat them unkindly in the first place.
Reposted by Prof. Joey "Barely a Footnote" Neilsen
It’s the first night of Hanukkah and the world seems like a very dark place. But we can bring light to the darkness. We can fight for each other and make goodness, love, and community shine through.
Show me your menorahs and let’s light up the timeline!
Show me your menorahs and let’s light up the timeline!
December 14, 2025 at 11:39 PM
It’s the first night of Hanukkah and the world seems like a very dark place. But we can bring light to the darkness. We can fight for each other and make goodness, love, and community shine through.
Show me your menorahs and let’s light up the timeline!
Show me your menorahs and let’s light up the timeline!
Reposted by Prof. Joey "Barely a Footnote" Neilsen
A thread about the introduction of quanta, the secret origin of Boltzmann’s constant, and the disastrous impact of quantum mechanics on one man’s appearance. 🧪 ⚛️ 🎢
December 14, 2025 at 6:05 PM
A thread about the introduction of quanta, the secret origin of Boltzmann’s constant, and the disastrous impact of quantum mechanics on one man’s appearance. 🧪 ⚛️ 🎢
Reposted by Prof. Joey "Barely a Footnote" Neilsen
Is it a Christmas sweater? No.
But.
Is it a Christmas sweater? YES.
But.
Is it a Christmas sweater? YES.
December 12, 2025 at 11:28 PM
Is it a Christmas sweater? No.
But.
Is it a Christmas sweater? YES.
But.
Is it a Christmas sweater? YES.
Is it a Christmas sweater? No.
But.
Is it a Christmas sweater? YES.
But.
Is it a Christmas sweater? YES.
December 12, 2025 at 11:28 PM
Is it a Christmas sweater? No.
But.
Is it a Christmas sweater? YES.
But.
Is it a Christmas sweater? YES.
When you need a linear algebra poem about steppe mammoths
"Mammuthus armeniacus"
Might spark fear but this has no basis.
Tho its tusks spanned 4 meters,
It weren't no meat eater, and
Decomposition's reduced it to traces.
Might spark fear but this has no basis.
Tho its tusks spanned 4 meters,
It weren't no meat eater, and
Decomposition's reduced it to traces.
December 10, 2025 at 4:44 PM
When you need a linear algebra poem about steppe mammoths