Yttrium barium copper oxide Updated +Created
Upside: superconducting above 92K, which is above the 77K of liquid nitrogen, and therefore much much cheaper to obtain and maintain than liquid helium.
Downside: it is brittle, so how do you make wires out of it? Still, can already be used in certain circuits, e.g. high temperature SQUID devices.
CIA 2010 covert communication websites / Wayback Machine crawl date search Updated +Created
Many hits appear to happen on the same days, and per-day data does exist: archive.org/details/widecrawl but apparently cannot be publicly downloaded unfortunately. But maybe there's another way? TODO select candidates.
Computer science course of the University of Oxford variant Updated +Created
Euclidean algorithm Updated +Created
Mineral Updated +Created
Minkowski inner product matrix Updated +Created
Since that is a symmetric bilinear form, the associated matrix is a symmetric matrix.
By default, we will use the time negative representation unless stated otherwise:
but another equivalent one is to use a time positive representation:
The matrix is typically denoted by the Greek letter eta.
Open X-Embodiment Updated +Created
GitHub describes the input quite well:
The model takes as input a RGB image from the robot workspace camera and a task string describing the task that the robot is supposed to perform.
What task the model should perform is communicated to the model purely through the task string. The image communicates to the model the current state of the world, i.e. assuming the model runs at three hertz, every 333 milliseconds, we feed the latest RGB image from a robot workspace camera into the model to obtain the next action to take.
TODO: how is the scenario specified?
TODO: any simulation integration to it?
https://web.archive.org/web/20250209172539if_/https://raw.githubusercontent.com/google-deepmind/open_x_embodiment/main/imgs/teaser.png
Original gangster Updated +Created
Try to fix your own bike before taking it to the shop Updated +Created
Sometimes you get annoyed to death with your bike not breaking or changing gears perfectly as you would like, and the people at the bike shop never do the job well enough.
The problem with bike shops is that the employees are already swamped with work, and they don't get paid any extra for doing more work.
As a result, paradoxically, they are often happier, and respect you more if you are trying to get them to help you to fix your own bike!
Also, for the same reason, they don't have the time to go for a quick test ride after a fix to ensure that the bug was actually fixed.
So they ignore things that would obviously be huge ridability benefits (although they might not be obvious to newbie customers), for which customers would gladly pay more money for.
But you start to learn how to do stuff yourself and it feel amazing when you finally get there (after infinite trial and error).
Ciro dreams of a bike shop that actually calls you for the appointment and then teaches you how to fix the thing.
So the best strategy is to have a backup bicycle, and when your main one breaks, you just try to to the fix yourself. That means:
  • identifying the broken piece
  • watching YouTube videos of how to do the job
  • buying a replacement and any missing tools on Amazon
  • giving it a shot
Then, if you fail to do the fix, that is OK, just take it to the bike shop, with the piece you've bought, and ask them to do it for you. At least this way you did not waste a golden opportunity to learn!
Monstrous moonshine Updated +Created
This is unlike atomic systems like trapped ion quantum computers, where each atom is necessarily exactly the same as the other.
Zeeman effect Updated +Created
Split in the spectral line when a magnetic field is applied.
Non-anomalous: number of splits matches predictions of the Schrödinger equation about the number of possible states with a given angular momentum. TODO does it make numerical predictions?
www.pas.rochester.edu/~blackman/ast104/zeeman-split.html contains the hello world that everyone should know: 2p splits into 3 energy levels, so you see 3 spectral lines from 1s to 2p rather than just one.
p splits into 3, d into 5, f into 7 and so on, i.e. one for each possible azimuthal quantum number.
It also mentions that polarization effects become visible from this: each line is polarized in a different way. TODO more details as in an experiment to observe this.
Video 1.
Experimental physics - IV: 22 - Zeeman effect by Lehrportal Uni Gottingen (2020)
Source.
This one is decent. Uses a cadmium lamp and an etalon on an optical table. They see a more or less clear 3-split in a circular interference pattern,
They filter out all but the transition of interest.
Video 2.
Zeeman Effect - Control light with magnetic fields by Applied Science (2018)
Source. Does not appear to achieve a crystal clear split unfortunately.
Zhuangzi Updated +Created
33 chapters. The first 7 are likely by Zhuang Zhou himself, and the rest a mishmash.
  • James Legge (1891):
    • ctext.org/zhuangzi side by side with Chinese, one chapter per page. Dividies it into three parts:
      • Inner Chapters
      • Outer Chapters
      • Miscellaneous Chapters
Nature Scitable Updated +Created
As of 2022 visible at: www.nature.com/scitable
Apparently they had a separate URL as just scitable.com, so they were somewhat serious about it before shutting it down.
As of 2022 marked:
This page has been archived and is no longer updated
RIP.
www.nature.com/scitable/blog/student-voices/ has last entry 2015, so presumably that's the shutdown year.
Self description:
Using our platform, you can customize your own eBooks for your students. Create an online classroom. Contribute and share content and connect with networks of colleagues.
so quite related to OurBigBook.com.
OurBigBook.com / Feature ideas Updated +Created
In this section we will gather some more advanced ideas besides the basic features described at how the website works.
OurBigBook.com / Manifesto Updated +Created
Education has become an expensive bureaucratic exercise, completely dissociated from reality and usefulness.
It completely rejects what the individual wants to achieve, and instead attempts to mass homogenize and test people through endless hours of boredom.
And the only goals it achieves are testing student's resilience to stress, and facilitating the finding of sexual partners. True learning is completely absent.
Teachers only teach because they have to do it to get paid, not for passion. Their only true incentive is co-authoring papers.
We reject this bullshit.
Education is meant to help us, the students, achieve our goals through passionate learning.
And, we, the students, are individuals, with different goals and capabilities.
The way we protest is to publish the knowledge from University for free, on the Internet, so that anyone can access it.
And we do this is a law-abiding way, without copyright infringement, so that no one can legally take it down.
We come to our courses just for the useless roll calls. But we already know all the subject better than the "teacher" on the very first day.
And we are already more famous than the "teacher" online, and through the Internet have already taught more way way more people than they ever will.
The effect of this is to demoralize the entire school system at all levels, until only one conclusion is possible: implosion.
And from the ashes of the old system, we will build a new one, which does only what matters with absolute efficiency: help the individual students achieve their goals.
A system in which the only reason why university exist will be to allow the most knowledgeable students to access million dollar laboratory equipment, and to pay the most prolific content creators so they can continue content creating.
No more useless courses. No more useless tests. Only passion, usefulness and focus.
Authy Updated +Created

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