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Ferromagnetic half levitation of LK-99-like synthetic samples

arxiv.org

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Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#231

Post by layer8 »

ironborn123 wrote: post #205
layer8 wrote: post #192

Earlier quoted context omitted.

That's not how probabilities combine.

You are right, but probability estimation of possibly novel phenomena is an ill posed problem. So either you do not model it at all, or come up with some mental model of what probability you are comfortable with and due to which factors; the factors being more important than the final number.

The exact numbers don’t matter, but your post indicates that you seem to have the wrong mental model of how to adjust your credences. The probability of each factor decreases the overall probability, not increases.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#232

Post by draw_down »

layer8 wrote: post #193
hliyan wrote: post #80

According to this: https://twitter.com/Andercot/status/1688598313497694208 "...there is a less well-known exception to this rule called Brauenbecker extension which provides a mathematical proof that levitation is possible with a simple diamagnetic in a dipole field so long as the diamagnetic material mass is very small relative to the strength of the magnetic field." I was very hopeful in the early days and was foll…

The amount of hyped discussion here on HN based on such scant evidence was astonishing.

[dead]

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#233

Post by jacquesm »

worrycue wrote: post #218
jacquesm wrote: post #216

Earlier quoted context omitted.

Exactly. That's the only reasonable stance. Everything else is just jumping to conclusions, positive or negative.

Sometimes a decision has to be made though - e.g. is a particular person a murderer. In most countries, the burden of proof is on the accuser and the accused doesn’t need to proven his or her innocence and is treated as innocent until proven otherwise.

Sure, but science isn't a murder trial, it is entirely evidence based. Show the evidence, if there is none we'll move on and if there is you get a Nobel (in the case of superconductivity at room temperature and ambient pressure).

We (the rest of the world) can't prove a negative, so it is up to the claimant to supply the proof. Given proof it will be believed, no proof then it's a no-op.

With the murder trial you can assume a-priori that there is a murderer, the question then is 'who', not if a murder is possible or not. These are entirely different problems for a logic perspective.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#234

Post by jacquesm »

JacobAldridge wrote: post #226
jacquesm wrote: post #213

Earlier quoted context omitted.

Sure, but every now and then people get into an argument with a Putnam prize winner or the inventor of some Internet Protocol details and find themselves caught out...

I would bet picodollars that rarely happens here…

Hehe. Nice one.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#235

Post by jacquesm »

jeltz wrote: post #230
JacobAldridge wrote: post #226

Earlier quoted context omitted.

I would bet picodollars that rarely happens here…

It happens more often than you think. For example it has happened a bunch of times that people have argued against PostgreSQL core developers about the internals of PostgreSQL. I know most of their usernames so it is always a great laugh for me.

I think you missed the GPs subtle point.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#236

Post by jacquesm »

willis936 wrote: post #221
jacquesm wrote: post #29

Earlier quoted context omitted.

I hope that ultimately it will come to that because I don't think anything else will put this to rest one way or the other (unless it is 100% confirmed/reproduced by another lab). It also seems to be the shortest path to a resolution.

That also adds little value. It would add no information on whether or not the sample is a fluke. We need to understand the material properties and its composition.

If it is a fluke or not doesn't matter. The only thing that matters is whether or not it is real, not how it was made. If it is real then we can expend a fortune on the 'how it was made' question, if it isn't real we can all descend from this holding pattern.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#237

Post by fnordpiglet »

jacquesm wrote: post #217
fnordpiglet wrote: post #135

Earlier quoted context omitted.

My bad, my reader view cut the tweet off and just showed the original. Still, his phrasing doesn’t indicate it’s over for him, just bordering - perhaps explains everything they’re seeing, but it’s : * not LK99 * a conjecture * isolated to magnetic properties that are acknowledged to be novel and don’t rule out messier effect * ignore other claimed properties like resistivity Also, something explaining everything you…

> I think it’s time for science to take the helm and hottakes to take a back seat for a while. It has been time for that from day #1. It either exists or it doesn't. Whatever people think won't make a shred of a difference and until there is replication if you want to look smart without doing any work you can pick 'it isn't real' (but boy will you look stupid if it eventually is) or 'it is real' (but boy will you loo…

Yeah I agree. I think it’s certainly entertaining, but my faith in the standard practice of science isn’t threatened by the social media / rapid experimentation. I’ve seen a lot of hyperbole about how this will replace methodical science and other malarkey and if it had been a slam dunk simple thing they would be crowing incessantly. But as these things are, it isn’t simple or obvious, and it require a meticulous process that can’t be easily supplanted by nitter feeds.

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#238

Post by willis936 »

jacquesm wrote: post #236
willis936 wrote: post #221

Earlier quoted context omitted.

That also adds little value. It would add no information on whether or not the sample is a fluke. We need to understand the material properties and its composition.

If it is a fluke or not doesn't matter. The only thing that matters is whether or not it is real, not how it was made. If it is real then we can expend a fortune on the 'how it was made' question, if it isn't real we can all descend from this holding pattern.

What benefit does that bring?

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#239

Post by whimsicalism »

killerstorm wrote: post #219
whimsicalism wrote: post #202

Earlier quoted context omitted.

No, not at all. Meissner effect is constitutive of SC

> Type-II superconductors do not exhibit a complete Meissner effect. Are type II superconductors not superconductors to you?

meissner effect != complete meissner effect, but i can see how that would be confusing

there was no meissner effect measured in this substance

Re: Ferromagnetic half levitation of LK-99-like synthetic samples

#240

Post by whimsicalism »

jeltz wrote: post #224
whimsicalism wrote: post #199

Earlier quoted context omitted.

It comes from lesswrong/rationalist circles. Best to ignore people once you have identified that they are on the wrong side of the Dunning-Kruger curve

No, let's not. I have seen examples here on HN where leading experts in the relevant field have been accused of Dunning-Kruger (I recognized the usernames, the accusers obviously did not). Such accusations are just namecalling and destroy any civilized debate.

Should we be reasoning from last usages of a phrase that you didn’t like or the particular context here?
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