You spin me right round baby

31 points · 30 comments · view on lemmy.world

30 Comments

87Six@lemmy.zip · 7 pts · 143d (21 replies)

It's funny to be in this community as someone that is science illiterate because I always learn that I'm too stupid to even understand the joke but I still laugh

rockerface@lemmy.cafe · 9 pts · 143d (17 replies)

So you know how you can turn any object around 360 degrees and it will return to its original position? With symmetric objects, that angle can be smaller, like you can turn an equilateral triangle by 120 degrees and it's still looking the same. You could assign numbers to these facts by saying that a normal asymmetrical object has a spin of 1 and an equilateral triangle has a spin of 3 (as in, it resets to its original position 3 times in one full rotation).

Now imagine an object that needs to be turned 720 degrees to return to the same position. Some particles are actually like that (electrons, for example). This is designated by a spin of 1/2 (as in, one full rotation flips it around, and it needs a second full rotation to reset).

This is obviously oversimplified, but then again, everything about quantum mechanics is.

dave@feddit.uk · 9 pts · 143d (1 reply)

This normally applies to microscopic particles, but it’s been shown that the spin of a USB-A plug is 1/√2 and the fact this could be taught and demonstrated in schools is why we all have to move to USB-C now.

rockerface@lemmy.cafe · 4 pts · 143d

I've always known the USB-A plug is some kind of 4 dimensional and/or quantum bullshit

xzinik@feddit.cl · 5 pts · 141d (2 replies)

Now imagine an object that needs to be turned 720 degrees to return to the same position. Some particles are actually like that (electrons, for example). This is designated by a spin of 1/2 (as in, one full rotation flips it around, and it needs a second full rotation to reset).

why the hell this is bringing me traumatic flashbacks of when i went in a rabbit hole learning why and how 4 dimensions rotations are used in 3d software to avoid gimbal locking

rockerface@lemmy.cafe · 5 pts · 141d

Ah, quaternions, good old fun. You can use them to describe these, too.

JennyLaFae@lemmy.blahaj.zone · 2 pts · 140d

Reminding me of how to turn a sphere inside out

https://youtu.be/Zv-XNlE1s8E

egerlach@lemmy.ca · 3 pts · 143d (8 replies)

My understanding is that the "rotation" or "turning" of fundamental particles isn't analogous to macroscopic objects, and that's where I start to lose things. (not seeking an explanation today, just pointing out where QM goes all fuzzy for me)

rockerface@lemmy.cafe · 6 pts · 143d (5 replies)

There are geometrical objects called spinors which are basically vectors with a half spin. Interestingly, they were introduced before we realized they could describe spin of electron and other particles like it. Sometimes a purely theoretical mathematical concept suddenly turns out to be describing very real things.

egerlach@lemmy.ca · 2 pts · 143d (4 replies)

So quarks are möbius strips? Got it. 😛

rockerface@lemmy.cafe · 0 pts · 143d (3 replies)

What you've got there is string theory

egerlach@lemmy.ca · 2 pts · 141d (2 replies)

Wait, how close is that to true? Does string theory really just boil down to "quarks are möbius strips"?

psud@aussie.zone · 2 pts · 140d

I feel like it was a joke; I don't think Moebius strips are at all relevant to string theory

Most of this stuff is really not amenable to language, and can only really be understood in the mathematics that physicists use

rockerface@lemmy.cafe · 1 pts · 140d

Not specifically Möbius strips, but the main premise is that all elementary particles are in fact strings in high dimensional space, and all of their unique properties come from the way those strings are shaped and moving.

Maybe there would be a particle that corresponds to a string tied in a Möbius loop, for all I know.

justme@lemmy.dbzer0.com · 3 pts · 143d (1 reply)

The problem here is that rotation makes only sense for objects that have a size. So you can say "this is the left side" and "now this part rotated to the right". This concept doesn't make sense for a particle that is a literal dot. The spin is a characteristics of particles that mathematically behaves like a rotation (freely speaking), therefore we treat it like that. That doesn't mean it is a rotation.

i_love_FFT@jlai.lu · 2 pts · 143d

The only thing to keep in mind is that although particles are dimensionless (as far as we know), the do not exist without context. Spin relates to how a particle is linked to the rest of the world.

One way of seeing it is that spin can be represented by a "rotational polarisation" of the surrounding cloud of virtual particles.

87Six@lemmy.zip · 2 pts · 143d

Why is my brain being fucked

quantum mechanics

Ah

Also, really fucking interesting. Jesus christ.

Kraiden@piefed.social · 1 pts · 143d (1 reply)

Know of any good visualizations of this? Because I have no idea what something has to look like in order to be spun 360 and be inverted from where it started. That has to be some 4th spatial dimension tesseract shit, surely. That breaks my brain!

eta: saw @rockerface@lemmy.cafe posted spinors which has some great illustrations... surprisingly less 4th dimensional than I was expecting, but still brain breaking

i_love_FFT@jlai.lu · 1 pts · 143d

There is the famous "belt trick", plus this PBS Spacetime really explains it well!

https://youtu.be/pWlk1gLkF2Y

All macroscopic examples of spinor involve an object attached to the exterior world. Electrons having spin 1/2 therefore imply that they don't exist "by themselves" and are embedded in a larger field.

I'm not sure whether that would be the electron field of the electromagnetic field, or maybe all of the fields?

Klear@quokk.au · 3 pts · 143d (2 replies)

Have you tried spinning? That's a good trick!

Kraiden@piefed.social · 4 pts · 143d

perishthethought@piefed.social · 1 pts · 143d

Are you suggesting I do a barrel roll?

silver_wings_of_morning@feddit.dk · 5 pts · 143d (1 reply)

The joke is that imagine an electron is a ball that is spinning around, only that it is not a ball and it is not spinning.

sunstoned@lemmus.org · 3 pts · 142d

Obviously spin is how the electron feels about being observed

DragonTypeWyvern@midwest.social · 1 pts · 143d (1 reply)

Look, we might not be able to tell you what spin is but we're actually quite sure that it is not spinning but it is nonetheless angular momentum.

That's spinning, you say?

Wrong, idiot. You absolute buffoon.

i_love_FFT@jlai.lu · 1 pts · 143d

This is bad popular science. Look at PBS Spacetime for a better way if doing it.

FartMaster69@lemmy.dbzer0.com · 1 pts · 143d (1 reply)

It’s a good trick.

OpenStars@piefed.social · 1 pts · 143d

Excellent point, FartMaster69.

Zozano@aussie.zone · 0 pts · 142d (1 reply)

As an Australian:

It's added to weed to make your bongs rip better.

psud@aussie.zone · 1 pts · 140d

It also "spins out" a small amount of pot so you can share it with more people