6 ms·
Researchers discover new third class of magnetism
- totallykvothe 2y agoWhat the heck is antiparallel and why is it different from perpendicular?
- bradrn 2y ago‘Antiparallel’ means parallel but pointing in opposite directions, like so: ↑↓ Whereas ‘perpendicular’ means pointing at right angles: ↑→ (And, of course, ‘parallel’ without qualification would mean pointing in the same direction: ↑↑)
- getcrunk 2y agoParallel without qualification should not imply direction?
- K0balt 2y agoMmmmm I don’t think you would say that two cars going opposite directions on a road , in opposite lanes, are on a parallel path, you would say they were on an opposite path, I would think. But if those two cars were traveling the same direction, in the same two lanes, they would be properly described as following a parallel path. from a line vs ray perspective parallel and opposite are equivalent, but when they are rays and not lines, directionality matters.
- getcrunk 2y agoEverything you added is context I.e. qualifications
- digging 2y agoContext is indeed what narrows the meaning of a word with various or broad meanings.
- theoreticalmal 2y agoMaybe the car metaphor breaks down sooner than you’d hoped?
- robertlagrant 2y agoJust like a real car.
- danwills 2y agoI don't think it does, but rather says whatever direction the first one is pointing in is exactly the same as the direction the second one points in.
- PittleyDunkin 2y agoParellelism doesn't imply directionism at all.
- gus_massa 2y agoFrom a mathematical point of view: no, no directionism at all. From a physicist working with spins point of view: yes, parallel has the same direction and antiparallel the oposite. Each area create their own jargon. Sometimes it's confusing to ousiders and when you pick a book from another area you must double check that the worlds mean what you think their mean.
- gilleain 2y agoFor what it's worth, protein structural biochemistry uses similar terminology for sheets. Since a strand has a direction (N to C), sheets are 'parallel' when neighbouring strands are pointing (roughly) in the same direction, and 'antiparallel' when pointing in opposite directions.
- phantomathkg 2y agoI think in this case as they are talking about force, it is a vector and implicitly imply direction. So antiparallel really means that the two force are pointing to opposite direction.
- PittleyDunkin 2y agoYou'd think they'd include a term that signaled this is about vectors then! I foolishly assumed this was a new term for "orthogonal", but words don't really need to be meaningfully related to their roots to be meaningful themselves.
- ajkjk 2y agoIt is a very standard term in physics at the undergraduate level.
- PittleyDunkin 2y agoSuch definitions may not make sense but it's still worth accepting them.
- seanhunter 2y agoIf you’re talking Euclidian geometry of infinite lines on a plane definitely yes. If you’re talking about vectors then you need an additional concept to capture the way the case of two vectors which fall on lines which in the Euclidian sense are parallel but point in opposite directions is clearly different from two vectors which point in the same direction also. This is like the difference between cars in parallel lanes on one side of a multi-lane highway and the oncoming traffic which would be antiparallel.
- deleted 2y ago[deleted]
- Ankaios 2y agoHere's the Nature article that the university press release links to: https://www.nature.com/articles/s41586-024-08234-x https://www.nature.com/articles/s41586-024-08234-x
- kergonath 2y agoThanks. I’ll take that over an over-hyped press release from a university PR person.
- hammock 2y agoReminds me very much of much of the frontier science Ashton Forbes (the crazy zero-point energy guy) has been exposing on Twitter. For example: "There is a very deep connection between magnetism and zero-point energy. So yeah, go ahead and build a magnetic motor. It's possible to draw this energy just using spins of electrons and permanent magnets." https://x.com/JustXAshton/status/1830621589848928459 https://x.com/JustXAshton/status/1830621589848928459 Unfortunately I can't find some of the more relevant posts I have seen recently. But maybe someone else on HN also follows this guy. Also: Magnet 900,000 times stronger than Earth reveals directional mass particles https://www.yahoo.com/news/magnet-900-000-times-stronger-140322722.html https://www.yahoo.com/news/magnet-900-000-times-stronger-140...
- whatshisface 2y agoJust because energy is there doesn't mean you can use it. You can only use changes in energy, like a battery discharging or a log burning. Zero point energy is the resting energy of empty space, and the only theoretical scenarios where it changes involve the laws of physics being changed and the universe being destroyed. In a sense it's the tension of having laws of nature. I sincerely hope it's not on the menu of consumable fuels. It's also worth mentioning that quasiparticles are bursts of energy that move through materials. For example a soundwave is a burst of quasiparticles, and the quietest possible sound is one quasiparticle, a phonon. I think this disclaimer should accompany all of the press releases about new particles discovered in condensed matter (solids, basically).
- Jarmsy 2y ago
- vlovich123 2y ago> They have the potential to lead to a thousand fold increase in speed of microelectronic components and digital memory while being more robust and energy efficient. Magnets are only used in spinning storage right? And SSDs are typically on the order of 3 orders of magnitude faster if not more in terms of IOPs due to random access performance being roughly the same as sequential. So is this saying 1000x faster than spinning HDDs because of latency or is it saying faster than even flash? I’m also not too familiar in how magnets show up in microelectronic components in a way that this would speed them up.
- aziaziazi 2y agoI also bump on the same sentence about efficiency, just after the one about IT carbon emissions. Doesn’t computation usually use way more power than storage? This looks like journalist trying to oversell it, I hope it’s too lunch skepticism and there’s really something here.
- grishka 2y agoNonvolatile storage by definition doesn't use any energy to retain data after it's been written. But an HDD needs some to spin either way while it's on, even when it's not currently being accessed. I can kinda see where they're going though — if this discovery enables increased bit density on magnetic media, you need fewer HDDs to store the same amount of data, so they use less energy when they're on.
- spwa4 2y agoHowever there's a major issue with SSDs. SSDs keep their data for ~10 years, which is a lot shorter than most people realize. "Spinning rust" will remain operational for longer and should keep the data for at least a century. You cannot have data on SSDs for backup or data hoarding. I get that spinning rust is put to shame by CD or DVD (even writable ones), but still.
- kissiel 2y agoThat sounds very optimistic. Do you have any data to back that up? Is it hot or cold storage? I understand, that the breakdown of magnetic field is indeed slow, but the HDD as a whole is not as sturdy, I think - you need to spin the platters, control the heads and so on.
- geniium 2y agoSurprised there are not more comment on this huge news. Is there another post I missed that is more viral?
- OhioMan2943 2y agoWelcome to the post science world
- Gigachad 2y agoThere's definitely fatigue around science news where media orgs massively over inflate or prematurely celebrate. Without actually being in the field yourself it's impossible to tell if any discovery is a nothingburger, 20 years away from meaning anything, or about to change the world. And most of the time it's the first two.
- OhioMan2943 2y agoThat's true, but I was more commenting on the loss of science from the public subconscious and our media outside of 7 second tiktok videos that link to current trends.
- robertlagrant 2y agoCurrently my source of truth is Sabine Hossenfelder, on YouTube. Worth a look. EDIT: she has a video on this[0] from 9 months ago! There you go. [0] https://www.youtube.com/watch?v=D0st_6sE7Bk https://www.youtube.com/watch?v=D0st_6sE7Bk
- ganzuul 2y agoIt makes you question what they mean by discovery. Is it not a discovery until it is published in Nature? On Arxiv this was a discovery in 2021. We can probably find a free energy channel in the YouTube haystack from a decade ago where the guy happened to arrange magnets in this order while going through permutations. Is that discovery or are only incumbent academics allowed to canonize science?
- intalentive 2y agoI didn’t even know there were two classes of magnetism.
- smolder 2y agoApparently the two classes are diamagnetism and paramagnetism. Best I can get from reading, diamagnetic materials are more random in their alignment (and repulsed by magnetic fields) and paramagnetic ones are more uniformly aligned (and attracted by fields). Can someone else explain it better? The article seems to be talking about some new type of ordered alignment. They say anti-parallel, which made me think of overlapping orthogonal alignments, where neighbors are kind of perpendicular, but the image shows vectors which are mostly just slightly off from parallel, creating those swirls.
- piannucci 2y agoAIUI, there is a technical criterion for an ambient EM field to imbue circuits within it with broken time-reversal symmetry. One example of a system that meets the criterion is a ferromagnet. Another is this altermagnet. One example of a system that doesn’t meet the criterion is a diamagnet. Another is the anti-ferromagnet. Roughly speaking, some systems are microscopically “asymmetric enough” to be useful in a certain way, and others are “too symmetrical.” Ferromagnets have a downside that altermagnets avoid: their microscopic fields don’t average out to zero over macroscopic distances. I think, but honestly don’t really understand, that the goal is to cause the material to treat currents of spin-up and spin-down charge carriers (think electrons or holes) dissimilarly. Constructing materials that distinguish between charge carriers of differing spin is a step towards spintronics. Again, I don’t know why that’s important, but it is what it is.
- foven 2y agoTo add a bit more to this, it's really a new class of magnetism. Traditionally we might think of ordered magnetic materials as being one of two: ferromagnets, which is what you think of when you think of magnets, and antiferromagnets. Antiferromagnets locally order their magnetic moments antiparallel so any which way you measure it, you measure no magnetization. The application is this: We would like to use ferromagnets and spin currents to make spin-electronic devices ("spintronic") where only the spin information is transferred without any large electrical currents. The goal of this is to save energy from Joule heating as spin can flow with significantly lower energy dissipation. Ferromagnets run into a lot of problems: they have a stray field, so patterned elements will interact and interfere with each other that sets a limit on how dense each nanostructure can be. Antiferromagnets have a big problem: they are extraordinarily difficult to measure and that is a challenge to overcome. So the benefit that altermagnetic materials presents is a clear union that tries to overcome the problems of both while retaining the strengths of both. The exact definition of the ordering of an altermagnet is a bit subtle and it mostly comes from an understanding of how the electronic band structure is different as compared with normal antiferromagnets.
- lokimedes 2y agoA new class of magnetism or magnet? Are we adding a new term to the equations or another bird to the catalog?
- freehorse 2y agoYeah a new class of magnetic materials, not a new class of magnetism. Not magnetic monopoles either. My brain hurts.
- marcosdumay 2y agoA new kind of solution for some equations that are way too complex for us to know all the ways they can go.
- deleted 2y ago[deleted]
- superidiot1932 2y agothe spirit of lk-99 lives on