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.
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?
Is it animal magnetism?
Can i make a ufo out of this?
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.
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.
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.
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.
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.
This reminded me of Richard Feynman talking about this very topic. Always enjoy rewatching it.
