Nitter: https://nitter.net/andrewmccalip/status/1687405505604734978#...
As someone new to the Twitter sphere - could some help me understand Nitter?
[deleted]
Andrew McCalip demonstrates synthesis of LK99
101–110 of 363 posts
Re: Andrew McCalip demonstrates synthesis of LK99
#102Nitter: https://nitter.net/andrewmccalip/status/1687405505604734978#...
Twitter is so slow to load on mobile that it's faster to hand-replace "twitter.com" with "nitter.nl" than to wait for the load time and the close the multiple pop-ups.
Re: Andrew McCalip demonstrates synthesis of LK99
#103Earlier quoted context omitted.
I was wondering this, why do all the samples not completely float. If the sample is only partially superconducting, could you just smash it into smaller pieces and find a few floating ones? Or would the different domains be so small that you have to turn the sample into dust before you get a completely superconducting piece? Probably can not be answered in general as it heavily depends on the synthesis process?
洗芝溪 answered this on Zhihu. All his answers are extremely good. This user knows something. 这应该还是材料的各向异性, 也就是它的准一维结构导致. 因为材料当中有一个固定晶相, 那个方向的抗磁性最强, 所以磁感线总会沿着这个方向走, 导致所有样品都是竖起来的. This should be due to the anisotropy of the material, that is, its quasi-one-dimensional structure. Because there is a fixed crystal phase in the material, that direction has the strongest diamagnetism, so the magnetic field lines will always g…
If the material is a one-dimensional superconductor where current can only flow with zero resistance along one direction, aligning that direction with the magnetic field lines should produce the weakest diagmanetism, because the magnetic force is proportional to the cross product of current and magnetic field. If the two are parallel, the force is zero.
Of course this could explain why the sample doesn't lift off: it starts out with the superconducting direction at an angle to the magnetic field and relatively strong diamagnetism leading to a righting force until the two directions are nearly aligned and the diamagnetism is too weak to overcome gravity.
Re: Andrew McCalip demonstrates synthesis of LK99
#104Earlier quoted context omitted.
As engineers we are given building blocks that we can build things from. Iron, steel, copper, plastic. Every once in a while a new building block arrives. It takes a while for us to figure out how to use it. But when we do, the world changes. - batteries + touch screens => iPhone - batteries got better => Tesla - reinforced concrete => pretty much all the worlds buildings and bridges - neodymium magnets + gyros => dr…
We're in a hurry in the sense that we don't want to leave investigation of this on the back burner for a few months, but we're not in a hurry in the sense that it's going to make any difference in practice whether a lab group reports today that they've reproduced it, or takes a bit more time to be careful and reports more thoroughly in two weeks time. Any first mover advantages are likely to accrue to the groups who…
From a scientific perspective, you are probably correct.
But think about it from a company/wealth creation perspective. Are you then really sure the correct course of action is to take it chill?
Re: Andrew McCalip demonstrates synthesis of LK99
#105This makes me extremely bullish about Varda Space, they have engineers of high quality and expertise that they could do a decent replication very quickly (if they got access to raw materials earlier, they might have been first to do so, comparable with the Chinese Groups) while working on their off time (from what I’ve seen of their twitter) and not a single big academic lab has managed to complete any sort of replic…
World first replication was done by Iris Alexandra using her own accelerated process and there is no way Varda Space could have beaten her.
Her rock actually floats. Did it all in the kitchen too. She should rightly be credited as first one.
Re: Andrew McCalip demonstrates synthesis of LK99
#106Earlier quoted context omitted.
I think you're joking, I'd 100% assume it, except that I ran into some truly bizarre US patriotism while trying to follow McCalip's updates a few days ago - last relevant one I could find was 'materials coming tomorrow' on 27th, but then I couldn't find anything about using them or any update. Just a decent into people tweeting (in thread) about how great America is, the best country, etc. Really surreal. Think it wa…
It's jarring for us Euros (I dunno, ghosts of the war are still alive maybe?), but it's pretty normal stateside.
Also, the Soviet Union, I think; it’s just bad associations all the way down. I realise that Americans have a different background and an American being really into flags and founding fathers and all that usually means something completely different (and less worrying) than someone in Europe doing same, but it’s still hard not to find it offputting.
Re: Andrew McCalip demonstrates synthesis of LK99
#107There is a Checz lab also documenting the process https://twitter.com/CondMatfyz
Re: Andrew McCalip demonstrates synthesis of LK99
#108Earlier quoted context omitted.
Doesn’t ring true for me at all, academia is many things but if your supervisor is onboard, you can generally do anything.
Okay still stuck in peer review then
For journal publish, yes but not for doing the actual work. If you find something interesting, you can go fast.
Re: Andrew McCalip demonstrates synthesis of LK99
#109Earlier quoted context omitted.
World first replication was done by Iris Alexandra using her own accelerated process and there is no way Varda Space could have beaten her.
Her rock actually floats. Did it all in the kitchen too. She should rightly be credited as first one.
More than that, she calculated how high it will float, and how height will depend on temperature, before starting the experiment, and confirmed all her predictions.
Re: Andrew McCalip demonstrates synthesis of LK99
#110FYI: you can use the x.com hostname when linking to tweets, e.g. https://x.com/andrewmccalip/status/1687405505604734978
Even better, you can use the nitter.net hostname and then you can even read the content even though you don't use X.