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Room temperature, ambient pressure superconductivity – this time for real?

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Re: Room temperature, ambient pressure superconductivity – this time for real?

#341

Post by zimpenfish »

jncfhnb wrote: post #239
slashdev wrote: post #179

Earlier quoted context omitted.

I think the most important thing is it proves it can be done. At one point it was thought impossible to run a 4 minute mile. There were all kinds of scientific sounding explanations why it just couldn’t be done. Then someone did it. Shortly after that, lots of people did it, because now people knew it was possible. If this is for real, it proves it can be done. Tons of money, work, and innovation will follow once peo…

I’ve heard this repeated. I vaguely recall it at least being a point of discussion in the novel Misery. But… that seems like such a stupid idea. What evidence could they possibly have suggested?

I think over time it's developed into one of those Just So stories whereas the reality is probably a bit more prosaic[0]

[0] https://www.scienceofrunning.com/2017/05/the-roger-bannister...

Re: Room temperature, ambient pressure superconductivity – this time for real?

#342

Post by jacknews »

retrac wrote: post #334
jacknews wrote: post #331

Earlier quoted context omitted.

My woo detector is blaring. superconductors can't carry arbitrary current. A lot yes, but dependent on the material, temperature, magnetic field, etc. And on the subject of the material, can it even be made into a wire? Is it stable? How much does it cost? So assuming it costs about the same as copper, what are the benefits? 0% loss, vs, maybe 10%? So the grid is 10% more efficient? I mean, that's definitely useful,…

I phrased it poorly - from an engineering standpoint, the amount of power a superconducting power line can carry is effectively limitless for practical purposes, in relation to the amount of material required. But yes, of course -- as I did say, eventually enough current flows that the magnetism induced breaks down the superconducting effect. > what are the benefits? 0% loss, vs, maybe 10%? With current lines, yes, r…

Sure I'm excited too, it can improve many fields. I'm just more cynical about the theoretical applications versus the more likely grungy practical reality.

And a bit fed up with the hype - along with fusion it's been the holy grail, and presented as some kind of salvation, for 40 years or more.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#343

Post by rasz »

jncfhnb wrote: post #239
slashdev wrote: post #179

Earlier quoted context omitted.

I think the most important thing is it proves it can be done. At one point it was thought impossible to run a 4 minute mile. There were all kinds of scientific sounding explanations why it just couldn’t be done. Then someone did it. Shortly after that, lots of people did it, because now people knew it was possible. If this is for real, it proves it can be done. Tons of money, work, and innovation will follow once peo…

I’ve heard this repeated. I vaguely recall it at least being a point of discussion in the novel Misery. But… that seems like such a stupid idea. What evidence could they possibly have suggested?

Dont know about the mile thing, but I can bring another anecdote - modem speeds and breaking 33.6Kbit barrier on ~3.5KHz BW limited wires.

Oral History of Brent Townshend (inventor of 56Kbit PCM modem mode) [Computer History Museum] https://www.youtube.com/watch?v=QqudP6ojEDI&t=6049. Transcript:

they've been trying to get modems to go

faster and there's this whole thing called

shannon information theory which says theoretically given

all the parameters of that copper line

and what's going on that the maximum

speed would be 35 kilobits per second

you can't go faster than that it was

theory they're you know 95 percent of the way to the theoretical

limit and michael had this engineer that

worked with him andy norrell which is like a

genius engineer um he's really amazing

understands modems and everything perfectly and

and michael recounted you know every six

months or so you talk to andy and say

you know you're sure there's no way that

we can go faster andy would say

no you can't go faster than that

this is the limit there's not any way

and so so michael was on the phone with

me and i said i have a way of going

faster and you know well you know a lot

of people think so but we think it's

max p and i say well i've got these

credentials i've been working at Bell Labs

he said wait a second i got to get somebody

else in the room too i get andy and you know

andy comes in on the conference call

and michael asking you know is there

any way to go faster than 33 he says no

35 is the limit and you know theoretically

and i said well you can do it like this you

know i say in like three sentences you

could do this and this and this

and then he says oh yeah that would work

Re: Room temperature, ambient pressure superconductivity – this time for real?

#344

Post by Lewton »

andersa wrote: post #318

It seems a third paper was just found an hour ago. Original paper: http://journal.kci.go.kr/jkcgct/archive/articleView?artiId=A... Translation: https://www.docdroid.net/UiUrs8c/kci-fi002955269-1-pdf Translation source: https://twitter.com/andrewmccalip/status/1684700783852556288

“Just found” It was linked in the original hacker news thread

Re: Room temperature, ambient pressure superconductivity – this time for real?

#345

Post by oefrha »

mrtranscendence wrote: post #335
Mizza wrote: post #284

Earlier quoted context omitted.

Some schmo with an instant coffee company. There's no need to surface random people's opinions.

I mean, he has a PhD in physics, at least. He's not just some rando off the street.

I was a high energy theorist and I even went to the same school as this guy (Princeton). I’ll admit I’m a complete rando when it comes to superconducting materials. PhD in an unrelated subfield means very little. I guess it helps with grokking academic drama.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#346

Post by AdamH12113 »

jacquesm wrote: post #267
AdamH12113 wrote: post #263

Earlier quoted context omitted.

Sure, the inductor conduction losses would go away (and that's a substantial improvement!), but I'm not sure what you're talking about with regard to reducing switching time. I don't think the MOSFET gate drive is limited by the wire that connects to it.

It isn't but the capacitor that is sitting on the far end of that circuit is limited by how fast you can pump current in or out. And if your current can go up considerably then the capacitor will charge that much faster and so your losses will be smaller because for the same 'on' duration of the MOSFET you can move more charge. Clearer now?

The output capacitor in a buck converter is charged through the inductor, whose current is continuous. I think we must be talking about different things.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#347

Post by psychoslave »

yreg wrote: post #332
psychoslave wrote: post #94

Earlier quoted context omitted.

Still make me laugh. I doubt the 2017 transfer costed $10. Let’s just recall all the more that domains are never really own, and that seems all the more crazy to my mind. Though I guess that when you let single individuals able to claim indefinitely large amount of ownership, that’s unavoidable waste of resources.

Buying x.com domain name is the last thing I would critisize on elon.

I don’t criticize any individual for simply implementing what the social structure lead them to do. That is, my messages were not meant into "name and shame" any specific person. That’s really the overall social game that I found laughable.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#348

Post by bluerooibos »

in3d wrote: post #158

LinkedIn post from one the authors: https://twitter.com/8teapi/status/1684571913908293633

So it took them 1000 times to get a good result from this experiment over 19 years, and two steps in the process require a stroke of luck?

That doesn't inspire confidence.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#349

Post by bluerooibos »

sudosysgen wrote: post #312
lamontcg wrote: post #266

Earlier quoted context omitted.

https://twitter.com/8teapi/status/1684571913908293633 Lee was stuck as an adjunct professor for 19 years. Kim thinks that physicists all have their head up their ass and he knows the shortcut to discovering superconductivity. And nature wouldn't publish their paper. Combined with their inability to accurately measure Tc and a lot of skepticism already out there that their graphs show what they say they do this looks…

That graphic isn't saying there's a shortcut, it's basically saying that physicists need to work harder and try many many many many more materials than they do. Not quite trial and error since the classes of materials should be informed by some theory, but far more - multiple thousands per individual.

He states it took 1000 attempts with two steps in the process requiring a "stroke of luck". This doesn't sound like it's going to be easy to replicate or verify.

Re: Room temperature, ambient pressure superconductivity – this time for real?

#350

Post by pushkine »

sergiotapia wrote: post #25
mijoharas wrote: post #2

So, has anyone seen any of the replication studies start coming in yet? From what I've read we seem to be waiting on those. (and I think they're likely coming today or tomorrow?)

There's a dude on twitter who's replicating it himself first-hand. He has the know-how and the process is "trivial" in his own words. https://twitter.com/andrewmccalip

If you scroll far enough he says he can't purchase Red Phosphorus without a DEA license or waiting weeks for a permit
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