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Re:LK99: Team of Southeast University observed zero resistan... by carabiner on Wednesday August 02, 2023 @05:23PM (#36977720)
As a layman, how do you know this is huge?
Re:LK99: Team of Southeast University observed zero resistan... by d1str0 on Wednesday August 02, 2023 @05:31PM (#36977857)
Assuming they discovered a low cost, room temperature, room pressure, superconductor, there are many HUGE technological advancements that can be made that would impact your daily life.

Possibilities include improved battery longevity in all devices(probably in an order of magnitude), low friction transport improvements (ie. cheaper high speed rail), and faster and higher bandwidth wired connections.

https://en.wikipedia.org/wiki/Technological_applications_of_...

Re:LK99: Team of Southeast University observed zero resistan... by carabiner on Wednesday August 02, 2023 @05:49PM (#36978138)
No I mean why is this "huge" when each time that's happened it's been deflated within 12 hours:

- initial LK-99 paper upload on Arxiv: HUGE, then it's probably nothing until replication (waiting)

- DFT release: HUGE, then probably nothing (DFT has poor predictive power)

- 110K SC: HUGE, then ... ?

In every case it's been the laymen saying HUGE, then the experts saying it's probably insignificant. Then the laymen settle on what the experts said.

Re:LK99: Team of Southeast University observed zero resistan... by throwanem on Wednesday August 02, 2023 @06:16PM (#36978501)
Derek Lowe is a layman? I grant his specialism doesn't precisely match the field, but it's easily close enough I'd expect him to be able to smell bullshit on this if there was any, and his latest "In the Pipeline" suggests much more the scent of roses.
Re:LK99: Team of Southeast University observed zero resistan... by whimsicalism on Thursday August 03, 2023 @01:10AM (#36981633)
Derek Lowe is saying 'this is maybe possible', commentators on Hacker News are saying 'this is practically a done deal, and here are the implications'
Re:LK99: Team of Southeast University observed zero resistan... by tigershark on Wednesday August 02, 2023 @06:03PM (#36978320)
Why are you always trying to ignore every new positive result since the beginning? Maybe because you are scared of getting called out for throwing literal sh*t at what it seems to be a very fundamental discovery in the worst case and in the best case a world changing, nobel prize worth research?
Re:LK99: Team of Southeast University observed zero resistan... by lannisterstark on Wednesday August 02, 2023 @08:30PM (#36979788)
It is not that they are throwing s** at it, but rather that none of you have actually explained why this is actually "huge," as you have been saying multiple times but without actually providing any concrete examples. "It is huge, trust me bro," isn't it.
Re:LK99: Team of Southeast University observed zero resistan... by cogman10 on Wednesday August 02, 2023 @06:42PM (#36978828)
> improved battery longevity

No

> probably in an order of magnitude

Absolutely not.

> Low friction transport improvements

This material is superconductive at 110K (-163C). Not exactly usable for transport applications.

> faster and higher bandwidth wired connections.

Absolutely not, resistance has no impact on bandwidth.

I've seen variations of this comment on hacker news. Superconductors are not magic dust to make things better. They are conductors with 0 resistance. There are certainly applications for that (see the wiki you linked) but like all things based in reality those are all a lot more muted and probably not possible with the current materials.

You are getting excited about the possibility of wires. There are certainly cool things you can do with a nice wire, but it's still a wire. You can't store power much with it, It's too big to make logic circuits with, and applications (like levitating a train) require too many amps for our poor wire to remain a special wire. (Most super conductive materials lose conductivity when amps are too high).

Re:LK99: Team of Southeast University observed zero resistan... by snitty on Wednesday August 02, 2023 @07:15PM (#36979194)
>and applications (like levitating a train) require too many amps for our poor wire to remain a special wire. (Most super conductive materials lose conductivity when amps are too high).

I was wondering if there was a current limit on superconductors.

1) Is there any understanding as to why superconductivity breaks down at higher amperage? 2) If so, is there any explanation as to why that doesn't require a PhD in physics?

Re:LK99: Team of Southeast University observed zero resistan... by cogman10 on Wednesday August 02, 2023 @07:27PM (#36979314)
> Is there any understanding as to why superconductivity breaks down at higher amperage?

This is a good read [1]

> As long as the induced magnetic field at the edges is less than the critical field, the material remains superconducting, but at higher currents, the field becomes too strong and the superconducting state is lost. This limit on current density has important practical implications in applications of superconducting materials – despite zero resistance they cannot carry unlimited quantities of electric power.

Tl;Dr (and probably wrong) as current flows through any conductor it creates a magnetic field. In superconductors when that magnetic field gets too strong it impedes current from being able to flow. A little like a traffic wave [2]. Everything works fine so long as there's enough space between cars to allow for them to speed up and slow down, but as the density of the cars increases if someone slows down that has a reverberating effect down the chain.

The magnetic field on a superconductor in turn induces a current on the conductor in the opposite direction.

Here's a video discussing some of the implications of this effect in a way that seems counter intuitive :) [3]

[1] https://en.wikipedia.org/wiki/Critical_field

[2] https://en.wikipedia.org/wiki/Traffic_wave

[3] https://www.youtube.com/watch?v=oI_X2cMHNe0

Re:LK99: Team of Southeast University observed zero resistan... by P_I_Staker on Thursday August 03, 2023 @09:41AM (#36985780)
as always the smart comment, ignore ant, them all
Re:LK99: Team of Southeast University observed zero resistan... by vl on Wednesday August 02, 2023 @06:04PM (#36978340)
I don’t know why people say it’s huge, so far all the images released show it is tiny.
Re:LK99: Team of Southeast University observed zero resistan... by saberdancer on Wednesday August 02, 2023 @06:04PM (#36978343)
Until today main hypothesis was that it is a scam by original team or a mistake when measuring resistance.

Now it looks unlikely as it would be very strange to luck into a new superconductor (pretty "good" one too) if they were faking it. It also means it is unlikely they made fundamental measuring mistakes such as thinking the sample is in room temperature when it was at 100K.

What seem plausible is that the process to make the material is not well defined and that there is high degree of variability. Even this chinese 110K replication only one of 6 samples shows superconductivity, meaning there is much room for improvement, perhaps with fine tuning they will find sample with characteristics that Korean team observed.

Re:LK99: Team of Southeast University observed zero resistan... by tgtweak on Thursday August 03, 2023 @11:28AM (#36987231)
Some potential applications for disruption:

Sub-sea cables that are the size of current fiber-optic bundles, which can transmit terawatts of energy with minimal/no losses. The bottom of the ocean is, ironically, at much higher pressure than atmosphere and would actually help increase the tolerances for superconductivity. This means: areas that have abundant power resources can export it with minimal infrastructure costs. Installing the transmission lines in this manner would be orders of magnitude cheaper than current high voltage DC transmission, and could likely bridge entire continents together. The #1 hold back on offshore wind is getting the energy from the farm to the onshore landing point. The energy loss and step-up/step-down transformers, with maintenance on those in kind, can be 30-40% of the project cost. You can also eliminate expensive and inefficient transformers on both ends since you can leave the voltage at generation-levels vs stepping it up to hundreds of thousands of volts in order to transmit it, which adds a lot of complexity. Under-utilized Hydroelectric capacity in northern Quebec could power Southern US states.

The carry on from this in terms of the reduction in required infrastructure for power transmission and delivery is massive. Think of all the copper and aluminum required today to build huge transformers, step up and step down electricity, and get it from the generation plants to your home or business. You could effectively power an entire household on a cable the size of a fishing line compared to cables the size of a sharpie.

The same applies to electronics - if there is a way to use this superconductor in transistors and microchips - the heat loss from operation could be reduced to nil, meaning you can have a chip with little/no thermal loss while operating. This eliminates the need for expensive cooling (again, typically copper or aluminum) and also all the complexity/cost associated with that. The power consumption of these chips is typically a result of the electricity losses as the current is driven into the chip at low voltage. Less thermal waste means much higher efficiency chips, which means less power required to operate them, which means much less consumption (and battery required to supply it). Mobile phones built with superconducting components and chips could last weeks on a standard battery since almost all the power consumption would be the radio, speakers and the screen.

Since the superconducting temperature claimed by the initial team (127 °C) is much higher than most ambient temperatures, this means the potential applications are essentially anywhere outside of a heat source.

Batteries and battery packs could be miniaturized to some extent - reducing transmission losses and eliminating heat on low voltage power means you can reduce the amount of copper required in a battery pack, and inside the battery itself, by a significant margin. This leads to lighter batteries out of the gate. Coupled with lighter cables to carry the power and lighter/cooler electronics to manage and distribute that power and manage the heat - the weight savings could be very significant.

The potential for miniaturization and displacement of heavy/expensive/bulky traditional conductors is very large and not possible to understate.