Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The first room-temperature ambient-pressure superconductor?

arxiv.org

Post reply on HN
Print view View original

401–410 of 906 posts

Re: The first room-temperature ambient-pressure superconductor?

#401

Post by thehappypm »

andreiklochko wrote: post #389

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

They've just proven (if true of course) that it's possible at all. That is a massive, massive leap.

And once it's possible, it won't be long until it's optimized. We've seen this everywhere -- transistors were once huge and now nanometers; solar cells have improved in every where; batteries are cheaper and better than ever.

Re: The first room-temperature ambient-pressure superconductor?

#402

Post by marcosdumay »

cududa wrote: post #197
skunkworker wrote: post #185

https://www.youtube.com/watch?v=EtVjGWpbE7k This is an unlisted video of the LK-99 film (purportedly)

I need someone to burst my bubble, this is too exciting

Expect the first iterations of that material to not actually hold currents well in a long (macroscopic) distance and create much weaker magnets than one would expect from a random superconductor.

But it's also a surprise for theoreticians, and I guess the mechanism is very prone to improvement.

Re: The first room-temperature ambient-pressure superconductor?

#403

Post by CamperBob2 »

andreiklochko wrote: post #389

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

That's the D part. This is just the R part.

Re: The first room-temperature ambient-pressure superconductor?

#404

Post by doctorwho42 »

dspillett wrote: post #27
noiv wrote: post #7

Earlier quoted context omitted.

I share your doubt, but on the other hand I wonder why? Could you tell how a breaking message of this magnitude should be decorated to make all doubts go away?

> Could you tell how a breaking message of this magnitude should be decorated to make all doubts go away? You'll never make all doubt go away on a new extraordinary discovery, mainly because most claims of an extraordinary discovery turn out to be mistakes (like the FTL neutrino thing a while ago that turned out to be a wiring fault that caused a minute timing error) or occasionally fabrications. A quiet publication…

The cold fusion people were actively touting data that didn't align to known fusion reactions. Like there are a limited number of elements one can fuse, but for some reason their reaction (which is known) had the energy off by like 300-400 KeV. For example: a proton signal of 2.6 MeV instead of the known 3MeV signal.

Re: The first room-temperature ambient-pressure superconductor?

#405

Post by fijiaarone »

doctorwho42 wrote: post #380
ccppurcell wrote: post #321

Earlier quoted context omitted.

It's a red flag for a physics paper. It's a coffin for a mathematics paper.

As a physicist, it's not a red flag... It's a red klaxon blaring out an alarm. I have only met a few physicists who don't write papers in latex. They are all 65+ and generally work with younger scientists/grad students who prepare the paper in latex for final drafts and submissions.

TeX was written in the 1970s for typesetting when there were no word processors by a computer programmer who couldn’t afford professional typesetting and couldn’t be bothered to learn assembly language so he wrote his own fictional one for his book — the same book he wrote TeX to publish.

Re: The first room-temperature ambient-pressure superconductor?

#406

Post by marcosdumay »

jacquesm wrote: post #318
marcosdumay wrote: post #301

Earlier quoted context omitted.

The only thing that holds a voltage without current flowing through it is an insulator.

This isn't even wrong. A voltage can be present without a current flowing. Touch any live wire to get an instant demonstration that there indeed was a voltage present even if no current was flowing. Not because the wire is an insulator but because it wasn't at that point in time conducting any current. Your finger (also not an insulator) closing the circuit however and then allowed current to flow.

Ouch, you need to take another look at that.

The definition of an insulator is a material that holds (up to some amount of) voltage without electrical currents appearing.

Your example needs two wires. And the wires themselves don't have any voltage. All of the voltage is between them, and is only there because they are insulated from each other.

Re: The first room-temperature ambient-pressure superconductor?

#407

Post by fabian2k »

andreiklochko wrote: post #389

Guys, even if everything in this paper is true, the material as it is might have limited applications. From what they show, the critical field and critical current seem very low. 2500 Oe is like 0.25 Tesla. Even REBCO at 77K is >1T. And 2500 Oe is not even at critical temperature but much lower. From skimming through the article I couldn't find the sample size of the current measurement to get the critical current de…

Just for comparison, an typical MRI magnet is 1.5 Tesla. An NMR spectrometer can go up to 28 Tesla (using new high-temperature superconductors). The LHC magnets are around 8 Tesla.

Those are the kinds of magnetic fields the classic superconductors and the newer high-temperature superconductors can achieve.

Re: The first room-temperature ambient-pressure superconductor?

#409

Post by eig »

swagmoney1606 wrote: post #207
eig wrote: post #179

A sister paper [0] has a photo of the material exhibiting the Meisner effect and levitating over a magnet, and claims to have a video too. Either they blatantly photoshopped the photo or they actually made a room temperature super conductor. I can’t see how the could have made a subtle mistake that resulted in magnetic levitation at room temp without making a superconductor. [0] - https://arxiv.org/abs/2307.12037

Video: https://www.youtube.com/watch?v=EtVjGWpbE7k I really need someone to bring me down a notch. This is too exciting!

That's not the video I'm referring to. It is a different experiment from Fig 4b in the paper, which is showing magnetic levitation.

I agree with swamp40: the video you linked is not demonstrating the Meissner effect, and is just showing Lenz's law.

Re: The first room-temperature ambient-pressure superconductor?

#410

Post by MisterTea »

Maxion wrote: post #162
obblekk wrote: post #150

The method to produce this material as described in the related paper [1] is fairly simple and could be done at home with a $200 home metal melting furnace from amazon and the precursors (which also seem to be fairly standard easy to obtain metals). If this is real, I'd expect some smart people from hackaday / youtube to reproduce this within weeks if not days. If this is real, it'll change society quickly and perman…

You need a furnace that can hold a vacuum, though.

Those are easy to make.
Post reply on HN