This article is a mess and badly written.
Basicly magnetism comes from electron spin orientation. There are two well known spin configurations.
Ferromagnetism: there is at least one electron with a spin that isn’t paired with an opposite spin electron. That atom then has a north and south magnetic pole. Like iron. Arrange all the atoms pointing the same way and you have a refrigerator magnet.
antiferromagnetism: all the electrons in the atom are paired with an opposite spin election. It’s complicated but basically they couple together and there isn’t a magnetic pole outside the atom. Like in copper.
Altermagnetism: what this article is about. You have a crystal of atoms with an unpaired electrons. The crystal would normally be ferromanetic. However they are arranged in a regular set of pairs that cause the electron spin to cancle out. Think of a checkerboard pattern where each white square cancels a black square next to it.
The antiferromagnetism and altermagnetism both have the spins cancelled out but the mechanism is different so there are different properties. Kramers degenerate vs wavevector.
In theory this gives you an extra state spin. So a magnetic drive uses a pattern of north and south to encode information. Ie NNSN becomes 0010.
With this you have north, south but also spin left, right. So you can encode more information.
How do you control the spin of an electron?
I know the usual way uses oscillating magnetic fields and it being very cold. There are other ways i’m not familiar with. I’m a classical computer engineer not a quantum computer engineer. I’m more used to energy bandgap then spin control.
Interesting… so like, if one were to use it on magnetic storage, you’d theoretically be able to work in quaternary?
Yup
While it is true Kramer outed himself as a degenerate at the smile factory in philadelphia I don’t believe this is an appropriate place to bring it up.
Sorta like linear vs. circular polarization in radio transmissions?
In the sense that it’s two different but similar states.
I’m pretty sure we can say it’s not actually spin now. Electrons have a charge and a magnetic field. If they are charged and spinning that world generate a magnetic field. So spin was used to describe the orientation of the field. The name for the state stuck
you seem knowledgeable on this topic. Enough that I hope you could answer my questions.
with this new state, would it make it easier/possible to improve not just efficiency but throughput of permanent magnetic motors?
also, you mentioned the programmability of magnets. would this allow us to build more “task specific” electric motors? for example; a motor with high torque at low rpms and low torque at high rpms?
This is a bit outside my field. That said I don’t think so.
The overall crystal should be very weakly magnetic. You want strong magnet with a high flux density so the electric field can push or pull against it.
I think this would be more useful in quantum computing as you get two bits polarity and spin. Or high density storage.
But who knows. There are clever physicists out there that know a lot more about this. They presumably see many more possibilities then I do. If the effect can be interrupted you could stitch between states. Like turning a magnet on and off. That would have uses like you described.
Thank you. That was explained very well!
There was a second?
I have no idea about the numbering, but I know of at least
- Ferromagnetism (like a fridge magnet)
- Antiferromagnetism (opposite of ferromagnetism at an atomic level)
- Diamagnetism (makes superconductors float)
- Paramagnetism (like that spinny frog)
These all indicate how a material reacts to a magnetic field. This article discusses “altermagnetism”, which is somewhere between ferromagnetism and antiferromagnetism.
Yeah, Paramagnetism.
Is that the kind that jumps out of aeroplanes?
Nah, it’s the one with the chair
This thread is already too smart for me
Pretty sure it’s the other non-brand name for acetaminophen.
That’s the copper one right?
No, the aluminum one.
That’s the copper one right?
Fucking magnets, how do they work?
Unironically, magnetism is similar to charge, which is similar to mass.
You (probably) wouldn’t ask “But why does an atom weigh anything?” or “why do opposite charges attract?” All these things are just intrinsic properties of matter: they just have them.
So the answer to questions regarding why anything has mass/charge/magnetic moment really come down to “they just do.”
Now, if you want to talk about how and why magnets work at a macroscopic scale, we can have a long and interesting chat about long range ordering and phase transitions, but I’ll leave that for now :)
There’s a lot more to it than “they just do” we just don’t know yet because there’s actually a lot we don’t understand about the fundamental properties of, well, fundamental particles.
See the higgs boson as for why matter has mass. We used to say “inertia is a property of matter” but some clever fucks figured out why and then proved it.
I would argue that the Higgs mechanism is just that: A mechanism for explaining where mass comes from. You could explain charge in a similar way by saying “because the particles are made of a certain amount of up or down quarks”.
Neither of these explanations answer the underlying question “but why does the Higgs mechanism give things mass?” or “but why do up/down quarks give things charge?”.
My point is that, at some stage, you get to the point of “the Higgs boson has mass because it’s an intrinsic property of the Higgs boson”, which is tantamount to “they just do”.
Mass & gravity are still way easier to understand on a fundamental level, especially since everything has a certain amount of mass and thus affects and is affected by gravity. It’s a much simpler concept. (“Natural”) magnetism is (so far) very material specific and I don’t think I’ve seen a good explanation as to why exactly. Magnets certainly behave very differently than other materials and that causes this mysticism in people when they think about magnets. Given the still ongoing research into magnetism and related things like superconductivity there’s certainly a lot still to learn.
In addition to “they just do”, the answer is also “we don’t know.” In that sense, icp was right.
💯༼ つ ◕_◕ ༽つ 🤡
Well, we do know why they work, but we don’t know why the way they work works.
This reminded me of Richard Feynman talking about this very topic. Always enjoy rewatching it.
The first time I saw this and he got to the part about your hand not going through the chair, and how magnets just do the same thing at a distance, it was like seeing the Matrix briefly. Definite “oh shit” moment. Also gave me a flashback of Sagan telling me that matter was basically comprised of nothing. By accident Lucas was right - the Force is all around us, binding us. It’s all forces.
I love watching Feynman prove icp right.
When I was much younger, I asked my dad why things obeyed the laws of physics. That seems similar to your questions in the second paragraph.
Still haven’t gotten a satisfactory answer.
The answer is because everything is lazy, and it’s easier to obey the laws of physics than not to. The path of least resistance is real.
Why are the laws of physics the way they are and not different? I have a degree in physics and I still don’t know the answer to that, annoyingly.IIRC, this is pretty close to what he said, except his degree was in engineering. Thank you for the response.
To that I would answer that things don’t “obey the laws of physics” in any greater sense than that the “laws” of physics are principles that we’ve formulated based on how we’ve observed that nature behaves.
We have exactly zero proof that there is some inherent property of nature that always and forever will prevent heat from moving from cold to hot, even though that would violate the second law of thermodynamics. It’s just that we have never observed a process that violates the second law (people have tried very hard to break this one), and have a decent explanation for why we’re not able to break it.
If some process is developed or observed that violates the “laws of physics”, that just means we need to figure out where the “laws” are wrong, and revise them, which is how science moves forwards!
So short answer: Things obey the laws of physics, because whenever we observe something that breaks the laws, we revise the laws to allow for the newly observed behaviour.
This is what makes science fundamentally different from most belief systems: The only core principle is that anything can at any time be disproven, and everything we think we know is potentially wrong. By truly internalising that core belief, there’s no amount of proof that can turn your worldview upside down, because your core principle is that everything you think you know is potentially wrong, only being a more or less good approximation to the true underlying nature of the universe, which we can never really know anything about.
I saw your comment much earlier but was in the middle of my workday and I didn’t have time to review it until now, so I apologize for the delay.
Your answer is interesting, insightful and educational, for all of which I am grateful. I hadn’t considered that perspective and it is all of the adjectives I listed previously.
However, I don’t think it answers at least what I meant by the original question, even if it does answer the literal question I asked. That’s on me for not using sufficiently specific language. What I meant wasn’t “why do things obey the laws of physics as we understand them” or “why do things obey the laws of physics as we’ve defined them” but more “whatever the laws of physics truly are as defined by the universe, what makes the content of the universe obey them?” I was quite young when I asked my dad the question, so at the time I pictured little Marvin the Martian style physics policemen following atoms around enforcing the law, but I suspect that’s not correct.
My question is possibly more philosophical than scientific (or realistically answerable). At that age I was certainly not aware of the simulation hypothesis, which seems like a good starting point, but also raises more questions. Regardless, I appreciate the clearly genuine effort behind your answer as well as the pontification it inspired, at least for me.
An aside: your comment reminded me of the “Maxwell’s Demon” Abstruse Goose comic (which sadly I can’t find to link here) and this Simpsons bit, which clearly I was able to find to link.
I want to reiterate one last time that people who try to answer questions and educate others are extremely valuable and I meant nothing negative about your comment. Thank you for responding.
Thank you for the kind response!
I was kind of considering that you might have meant the question that way (“why does nature obey whatever underlying law there is”), but as you say, it quickly takes us into philosophical territory.
If I were to give my honest opinion on that as a scientist, I would say that we can never know what the true, underlying guiding principles of the universe are, or even if there are any at all. We can only ever measure the laws of the universe indirectly through observations. This precludes us from ever being 100% certain about the true underlying principles that guide what we’re observing, or even if there are any.
As an example, there’s a hypothesis (can’t recall what it’s called) which postulates that the entire universe is in an unstable state. If that hypothesis is correct, the laws of nature as we know them could in fact change abruptly, with the change propagating at the speed of light. This change could amount to stuff like changing fundamental constants, which would pretty much break the universe as we know it.
I’m familiar (very vaguely) with the unstable universe. It reminds me of an author, Douglas Adams I believe, who wrote "There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.
There is another theory which states that this has already happened."
That’s a great quote! I just did some searching: I’m thinking about false vacuum, and can live with the fact that if our universe does decay, it will (according to this theory) happen at the speed of light, so it will be impossible to observe before we are instantly wiped out, which is a calming thought.
It’s funny because the actual physics explanation is “they just do”.
It’s the craziest part of quantum physics. “Why is this stuff having the observed behavior?”
Based on all evidence and theory, the answer is that it quite literally just does.
That is always the foundation. The axiomatic ground.
Water, fire, air and dirt
Fucking magnets, how do they work?
And I don’t wanna talk to a scientist
Y’all motherfuckers lying, and getting me pissed.
Is it animal magnetism?
I’m too stupid to understand what that article is talking about. Can someone translate to layman’s terms?
I could be wrong but as I understand it. You know magnetism based on positive and negative poles, now they can read and write SPIN, which is another property of electrons (that are in everything, even things nonmagnetic). If it’s true, and scales, we could use non-ferrous better materials to achieve what we do currently with ferrous materials.
Sooo we can magnetize nonmagnetic materials?
Tractor beam when?
Sadly still magnetic force that loses strength exponentially based on distance
To quote Tim The Toolman Taylor, “Moar Power!”
chatgpt can eli5 summarize. who knows if its accurate enough
ChatGPT cam bullshit about anything, but odds are anything complex will be wrong.
Even simple things are probably wrong.
I would not even trust it to summarize nuanced details in a lengthy article, let alone something science related (especially about new discoveries).
What value is a summary when you fully acknowledge that you can not trust it for accuracy?
i agree, but what can you trust for accuracy in these times?
People who are experts in the subject.
Propegandists thrive by trying to convince people that they can’t trust anyone, because it makes foolish people believe that every voice carries equal merit.
How many Rs are in orange
There are no Rs in orange
Yeah I’ll be using chatGPT for education, what could go wrong
Can i make a ufo out of this?
Worth a read, I feel like I read some hard sci-fi.
