Pinned Tweet
I've been a lot less active here lately: not too happy with the direction things are going. I'm more active on:
Bluesky: bsky.app/profile/steuard.bsk…
Mastodon: mastodon.social/@steuard
[Personal friends: I may have a Bluesky invite available. Let me know if you're interested.]
My mother's obituary ran in the Lincoln, Nebraska paper this morning. She mostly wrote it herself, a couple weeks ago, and it captures an awful lot of who she was: it's worth reading. My heart is filled with tears and love.
legacy.com/us/obituaries/jou…
If any of my friends here need Bluesky invite codes to help them move on, let me know. (Email is best: I haven't been checking in over here that often, and Musk's latest awfulness is making it awfully tempting to make that "almost never".)
Steuard Jensen retweeted
THIS WHOLE THREAD. When ppl say “we have to meet market demands” I hear “our students don’t deserve anything beyond what they can imagine at age 17”
This Post is from an account that no longer exists. Learn more
Steuard Jensen retweeted
The 'failing schools' justification for vouchers falls apart when you consider the fact that the private schools to which legislators want to divert tax $$$ have no requirement to administer the state tests that are supposed evidence of public schools failing. #nced #ncga #ncpol
If you ever wanted to read more about Middle-earth but haven't known where to start, input your preferences and get a personalized list:
tolkien.slimy.com/booklist.h…
(Finally finished updating this hobby project just before I need to prep for my fall classes: yay!)
Family game night was supposed to end by 10pm but accidentally went to 11:30, so meteor watching wasn't going to happen. But after being woken up at 4am, I popped outside for 15 minutes. Despite lots of trees and annoying porch lights, I saw 5 meteors and 4 satellites. 🤩💖🌠
Thunderstorms coalesced overhead about an hour earlier than expected, so Ms12 and I made it back home from our bike ride today *just* in time. (Well, almost in time. The rain started seriously picking up during the long wait to cross the busy street three blocks away.) Still fun!
I've struggled so much with whether to mask in the classroom. The medical evidence seems strong that >10% of infections lead to some level of Long Covid and that risk is cumulative with repeat infections. But every term I worry more that my students will see my mask as a barrier.
Steuard Jensen retweeted
With a great deal of sadness, we now believe that the game is over. LK99 is NOT a superconductor, not even at room temperatures (or at very low temperatures). It is a very highly resistive poor quality material. Period. No point in fighting with the truth. Data have spoken.
Steuard Jensen retweeted
Massively under-reported science story because there's so much going on right now but...it turns out that we might have figured out what's causing this very scary spike.
Quick thread, on how WE'VE BEEN ACCIDENTALLY GEOENGINEERING FOR DECADES...but then we stopped:
Steuard Jensen retweeted
National Lab (LBNL) results support LK-99 as a room-temperature ambient-pressure superconductor.
Simulations published 1 hour ago on arxiv support LK-99 as the holy grail of modern material science and applied physics.
(arxiv.org/abs/2307.16892)
Here's the plain-english explanation:
- The simulations modeled what the original Korean authors proposed was happening to their material - where copper atoms were percolating into a crystal structure and replacing lead atoms, causing the crystal to strain slightly and contract by 0.5%. This unique structure was proposed to allow this amazing property.
- @sineatrix from Lawrence Berkeley National Lab simulated this using heavy-duty compute power from the Department of Energy, and looked to see what would happen to the 'electronic structure' of this material, meaning, what are the available conduction pathways in the material.
- It turns out that there are conduction pathways for electrons that are in just the right conditions and places that would enable them to 'superconduct'. More specifically, they were close to the 'Fermi Surface' which is like the sea-level of electrical energy, as in '0 ft above sea-level.' It's believed currently that the more conduction pathways close to the Fermi surface, the higher the temperature you can superconduct at (An analogy might be how its easier for planes to fly close to the surface of the ocean due to the 'ground effect' that gives them more lift.)
This plot in particular shows the 'bands', or electron pathways, crossing above and below the Fermi surface.
- Lastly, these interesting conduction pathways only form when the copper atom percolates into the less likely location in the crystal lattice, or the 'higher energy' binding site. This means the material would be difficult to synthesize since only a small fraction of crystal gets its copper in just the right location.
This is insanely bullish for humanity.
Wow. It's far too early for any sort of positive judgment, but this superconductor breakthrough might possibly be the real deal.
science.org/content/blog-pos…
It sounds like the simulation results alone could open new research programs.
Today is (was) Kim's and my "half our lives" wedding anniversary: 23 years. And, wow, I still break into a big grin whenever I first see her after being apart for a few days, and my life is so much richer for being interwoven with hers. I love you, Kim!
I know it's trivial compared with so much in the world (and even right here), but I find this X thing genuinely annoying on multiple levels. I still care about the interactions and experiences that I've had on this site, but I'm on the verge of leaving purely out of spite.
Steuard Jensen retweeted
If grad students truly were a drag on university finances, uni's would (a) massively fund-raise for grad programs and/or (b) shut them down. The fact that there's lots of infrastructure to enable/encourage bringing in more grants and hence grads means clearly the opposite.
This Post is from an account that no longer exists. Learn more















