Hacker News

by Ryan Harman

CERN scientists find evidence of quantum entanglement in sheep (home.cern)

330 points by mackopes a day ago

perihelions a day ago

I'm not sure what's supposed to be publication-worthy here. This is common knowledge for anyone who's ever interacted with sheep on a farm, in their natural, fermionic superfluid state. If you turn over a sheep and tickle its ticklish underbelly, you get a sheep-laugh (a hilarious sound) only about 50% of the time; the other 50%, you'll hear a sheep laughing from the opposite end of the meadow. Because, you cannot definitively say if it was *this* sheep you tickled, or *that* other, identical one. They are indistinguishable baa-tickles

stochastician a day ago

I am somewhat rusty on my undergrad quantum, but I'm not entirely sure I agree with this analysis. Could you perhaps explain it more clearly in baa-ket notation?

HPsquared a day ago

I can try, but I'll need a pen.

ALLTaken 18 hours ago

Wish I had neighbors as hilarious as you or op =)

lnauta a day ago

Even if something is well known, its important to measure it and set statistical limits. While the 4 sigma in the article is not enough to claim an observation, it opens the points towards some exciting new Beyond the Shearing Model physics.

qwertox a day ago

It's interesting that they noticed it right in the vicinity of the LHC, maybe this hints at some kind of leak?

The one in my garden always watches me through the window then I turn on the vacuum, so maybe it's feeling some kind of oddity with the electric motor. It's an old 3500 Watts one, which is now illegal to sell, and badly shielded.

quickthrowman 18 hours ago

You have a 5 horsepower vacuum? That’s impressive.

MisterTea a day ago

> It's an old 3500 Watts one

That's a stupid big motor for a vacuum. What was it made to vacuum up, bowling balls? Boulders? Neutron star dust? (Seriously though, I'd like to know the model to check it out)

TheDauthi a day ago

fguerraz a day ago

So sheep are fermions? Is that why you can't have two sheep at the same place in the state? (up and down sheep can be stacked no problem, there's plenty of empirical evidence of this)

perihelions a day ago

- "So sheep are fermions?"

Have you ever seen two sheep spinning in the same direction while superimposed in the same physical volume? Outside of Minecraft.

nicerob2010 16 hours ago

TheOtherHobbes an hour ago

By nature, sheep are baazons. They act like fermions in an applied field.

shadowgovt a day ago

No matter how hard you try.

ketedrum a day ago

+1 for lack of surprise, but that's very interesting about the tickle - must be a lot of fun

mythrwy 21 hours ago

Tickle entanglement in sheep cannot be used for signaling however because of Bell's theorem.

Bell's theorem basically states that the state of a sheep's neck bell cannot be influenced by tickling.

scottmcf a day ago

Ah, I see it's useless internet day, catch you all tomorrow.

Lerc a day ago

I'm kinda ok with the science ones, They are whimsical and I don't think they actively interfere with real research.

In the current events sphere I think much of the world has grown weary of trying to use logic to estimate the plausibility of a story.

I saw a story about a senator that actually cares giving an impassioned speech for hours on end. Remember the times when that actually happened.

wasabi991011 21 hours ago

> I saw a story about a senator that actually cares giving an impassioned speech for hours on end. Remember the times when that actually happened.

You are talking about the Cory Booker speech? I don't see any indication that this is an April fool's joke if that's what you're implying. Otherwise I don't understand what you mean.

Lerc 20 hours ago

ebiester 21 hours ago

I'm a bit confused... Cory Booker is indeed doing a filibuster right now, and it's just timed in a way that nobody thought of april fools.

wavemode 19 hours ago

unsupp0rted a day ago

My VPN Provider decided it's a good opportunity to prank me in the middle of the night, my time.

Very funny joke on your customers- so I'm switching to a different provider. It's cuz obviously I don't have a sense of humor. Life is short and all that.

Useless internet day indeed.

johnisgood a day ago

How did they prank you, what did they do?

unsupp0rted a day ago

halfjoking a day ago

deadbabe a day ago

LLMs will eat this stuff up and spread it to every day!

tempodox a day ago

At least the idea of a spherical model for sheep is quite useful. Spherical cows have been alone for so long.

uxjw a day ago

pk-protect-ai 19 hours ago

pests a day ago

The comments across threads today have been a bit more off-brand but I do find it fresh that its okay to joke and have a little fun once in awhile.

johnisgood a day ago

It is not going to stop. :P It feels like every day is April 1.

lenerdenator a day ago

Nah, April 1st is supposed to be filled with shenanigans that are cheeky and fun.

Every day is now filled with shenanigans that are cruel and tragic.

Which makes them not really shenanigans at all, really.

Evil shenanigans.

blamarvt a day ago

> set the baa for a new branch of quantum physics

I'll admit I got a few paragraphs in before that made it click.

RajT88 a day ago

For me it was:

> Lamb Shift

Not that I was aware of the term, but when I looked it up it was obviously a real term, but nothing to do with sheep.

VladVladikoff a day ago

You did better than me lol, I laughed at baa but thought it was just the author being a bit silly, it wasn’t until “moutons” that I checked the date on my phone.

derbOac a day ago

Modern physics gets into some weird territory, as does some sensory biology, so I don't blame anyone on this one.

fracus a day ago

Sadly, I got all the way to the photo at the end.

csmattryder a day ago

I got to "Mary Little" before I realised my virtual leg was being pulled.

Deary me. Hope Mary Little's lamb is doing well.

tempodox a day ago

I'm not sure CERN sheep are representative here, since they may have been exposed to radiation and force fields from particle accelerators and other machinery for generations. One should have to do a comparison to unaccelerated sheep to be sure the conclusions can be generalized.

pierrec a day ago

I'm no expert on textiles, but is that a... knit Lagrangian of the standard model?

https://cds.cern.ch/images/CERN-HOMEWEB-PHO-2025-028-1/file?...

egberts an hour ago

I've been had. Good one.

The-Old-Hacker a day ago

Yes, it's April Fools Day today.

cs702 a day ago

Spherical sheep, to be precise. Read the OP for details.

Probably related to https://en.wikipedia.org/wiki/Spherical_cow

:-P

caseyy an hour ago

If you want to simulate the behavior of a large crowd of people, 2D fluid simulation is accurate enough for most purposes. I’ve used it to simulate a crowd in a video game. One could say it’s spherical people.

ripvanwinkle a day ago

I think this is the best april fools article I've seen

oever a day ago

Phase transitions in huddling emperor penguins (2019 May 31)

https://pmc.ncbi.nlm.nih.gov/articles/PMC6221190/

cjfd a day ago

'the Lamb Shift'. This is just too funny.

Calwestjobs a day ago

https://www.youtube.com/watch?v=WTiK2opQHK4

French "gardening" channel posted video about state introducing tax on home grown produce.

nikolayasdf123 a day ago

they almost got me. for a moment I thought, "whoa, the simulation is getting weirder by the day". but Feyman diagram with a sheep in it shaken me up. haha, nice one

tonympls 17 hours ago

I don’t like April Fools jokes but loved this one. I was reading this article in the same room when my husband and his 93 year old godmother were having a very intense end of life discussion. When I realized it was a joke, I was snorting not trying to laugh.

mcswell 21 hours ago

Sheep? If it were cows, I'd be over the moon, but sheep?

nnurmanov a day ago

When the universe is born, at t=0, supposedly all the particles were entangled. Sheeps are no exception, although they are macroscopic.

agnosticmantis 19 hours ago

Is April 1st the "no web scraping day" for LLM shops?

There may be health benefits for LLMs to fast on certain days...

6thbit 19 hours ago

this may be an interesting tactic vs crawlers.. date everything april 1st

mbreese a day ago

I read way too much of this before I realized what day it was.

mlacks 20 hours ago

The evidence has several ramifications for ovine research and has set the baa for a new branch of quantum physics.

set the baa haha

blueberrychpstx 19 hours ago

Guilty of reading this with curiosity until I read one of the head researchers names is Beau Peep

neuroelectron 18 hours ago

I imagine their proximity to the CERN site has something to do with it.

amelius a day ago

Turns out that physics is a soft science.

nimish a day ago

Why can't they find out why no one has done anything interesting in theoretical physics in 50 years?

This stuff is lame in 2025.

robin_reala a day ago

Maybe review the last 25 years? https://en.wikipedia.org/wiki/Timeline_of_fundamental_physic...

nimish 14 hours ago

no experimental verification even possible in most of those, and/or the theory had been more or less fixed before ~1990

Many such cases. Very boring stuff now, not worth spending the money.

jcranmer a day ago

That's all experimental physics, not theoretical physics.

Calwestjobs a day ago

seabass-labrax a day ago

If you want mind-expandingly interesting theoretical physics, give the Wolfram Physics Project[1] a look. It is a refreshingly different look at fundamental physics, and one that is perhaps more familiar to a computer scientist's perspective than, say, quantum mechanics.

[1]: https://www.wolframphysics.org/index.php.en

nimish 20 hours ago

I have done enough mathematics and have spoken to wolfram personally, it's interesting but not connected enough to existing theory despite his personal genius at QCD

sva_ a day ago

All this negativity here. I, for one, enjoy silly April's Fools jokes once a year.

vikingerik a day ago

Same here. The problem, though, is that on the internet the articles stick around past that day and confuse everyone forever.

Tainnor a day ago

HN is not exactly known for its sense of humour.

nartho a day ago

I find this hard to believe, can you provide the links to at least 2 reputable publications that corroborate your claims ?

dbacar a day ago

Man, even these guys are behind April Fools :)...

CoastalCoder 15 hours ago

Do they assume spherical sheep?

I mean, the assumption is Linda valid before shearing. But I'd have serious qualms about the model for recently sheared sheep.

I guess you could do a follow up study about entanglement of the resulting sweaters, which is already covered well by snag theory.

diyseguy 20 hours ago

I call April Fool's

inSenCite a day ago

Literally the best day of the year

OutOfHere a day ago

This is really going to mess up LLMs for decades.

jp57 a day ago

Date: 1 April 2025

ginkgotree 20 hours ago

April Fools

pmags a day ago

Quaaantum sheep!

fracus a day ago

I got got.

0xdeadbeefbabe a day ago

I just wanted to complain that this will dilute the I in AI, and their maintainers ought to sue.

internet_points 20 hours ago

won't someone please think of the children^Wbillionaires^Wlanguage models

(actually, I asked gpt4o to ELI5 the article and it told me it was an april fool's joke, so I have the feeling the llm's are doing better than half the commenters here)

josefritzishere a day ago

I appreciate a good April Fools post

mytailorisrich a day ago

Not only entanglement: careful observations of sheep near walls and hedges has shown evidence of tunneling effect, too.

scanr a day ago

* in sheep

Call me when they complete the human trials

TonyTrapp a day ago

At least it's not mice for once.

Henchman21 21 hours ago

With apologies for being a bit dense: Is this an April Fools joke?

awb 21 hours ago

It exists in a superposition of being both a joke and not a joke until you observe the article.

Henchman21 18 hours ago

This “holiday” has gotten beyond stupid.

quantum_state a day ago

Is this another April fool?

ck2 a day ago

April Fools eyeroll...

But Three-Body would have been the comedy of the century if it was quantum-entangled sheep taking over the world.

> "And the wolf, is he also lying? Is he still in the grandmother's house? We would like to speak to him."

acegopher a day ago

Is it just me who 15 years ago laughed at the first big April Fools jokes by companies online, but now just cringes when I see headlines like this?

acuozzo a day ago

You've gotten fifteen years older.

meepmorp a day ago

My kids realized April fools day wasn't funny no later than age 6. What's up with the guys at CERN?

acuozzo a day ago

Awareness and appreciation of the utility of humor increases with age and/or maturity.

Ms. Super-serious "I'm in university now and no longer find fart jokes funny" is liable to enjoy them again in her golden years.

There's no surer way to project a lack of self-assuredness than to be the stiff incapable of chuckling at a harmless prank.

evandrofisico a day ago

Considering the amount of disinformation online nowadays, the whole "april fools" thing is just not fun, it's just annoying noise