QuTech Academy Updated +Created
One of their learning sites: www.qutube.nl/
The educational/outreach branch of QuTech.
Eternity Wall Updated +Created
This website used to allow embedding text messages with OP_RETURN, here's an archive from 2015: web.archive.org/web/20150718052659/http://eternitywall.it/
As of January 2024, it seems to read-only mode, where it simply indexes matching transactions that were made via other means: web.archive.org/web/20230929075331/https://eternitywall.it/
There were 3191 hits for the search term:
git grep '\bEW '
in our data starting with tx a3b3af21514bd79a4cbcac9916a8514636a72d813539192214542fd85247082e (2015-06-24):
EW Eternity wall is live
up to the last entry on tx 28820bc14cf2cfda58ecbc9ac6df3f41a1cb90f4246543f01ba42a5e9dac3cf8 (2023-06-15)
EW May our friendship endure, signed by hg, kty, wjj, and xyz.
no doubt initials of 4 Chinesepeople. A blood brother oath comes to mind, akin to the Oath of the Peach Garden. Will these four be the ones to take down the evil dictator Xi Jinping?
The very first message gives away the name of what we assume is a web-based upload system, "EW" being its advertisement signature added to every message.
Running bitcoin-cli:
bitcoin-core.cli getrawtransaction a3b3af21514bd79a4cbcac9916a8514636a72d813539192214542fd85247082e true
shows that the messages are encoded with OP_RETURN:
  "vout": [
    {
      "value": 0.00000000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_RETURN 455720457465726e6974792077616c6c206973206c697665
Federal University of São Carlos Updated +Created
The Social Network Updated +Created
Video 2.
The Social Network: Eduardo Saverin tells the hearing how he was trapped into the shares dilution
. Source.
Video 4.
The Social Network: Eduardo Saverin tells the hearing how his shares were diluted
. Source.
Video 5.
The Social Network: I'm Not a Bad Guy
. Source.
ISO SQL TRIGGER syntax Updated +Created
TODO what is the standard compliant syntax?
SQLite does not support SQL stored procedures at all, so maybe that's why they can't be standard compliant here: stackoverflow.com/questions/3335162/creating-stored-procedure-in-sqlite
SQL:1999 11.38 covers "Trigger definition". The Abstract syntax tree starts with the CREATE TRIGGER and ends in:
<triggered SQL statement> ::=
  <SQL procedure statement>
This is defined at 13.5 "SQL procedure statement", but that is humongous and I'm not sure what it is at all.
Quotes and threes Updated +Created
Starting tx 2f201c8518c7b012c03c2c82e40e86f6aaf616ea5fbe22570aac9d2c6611cb68 (2023-03-11), the chain is flooded with ASCII transactions containing many repeated double quotes " and digits 3, with some other characters interspersed in them without any clear pattern e.g. the first one:
""""""""""""""""""""""""""""""""jk""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""'}""""""""""""""""""""""""""""""""/D""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""q1""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""XK""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
TODO what is up with that?
In that first trasaction the quotes appear as part of a Multisig output script.
Fabry-Pérot interferometer Updated +Created
Video 1.
Fabry Perot Interferometer by JFC UCL (2016)
Source. Description only, reasonable animations. Considers the case of two nearby beam splitters.
Video 2.
Fabry-Perot Introduction by Williams College Physics (2020)
Source.
Shows a working device. Confocal optical cavity, one of the mirrors scans back and forward moved by a piezoelectric motor, this is called a "scanning Fabry-Perot interferometer".
Does not produce an interference pattern, only an on/off blob, which is then fed into an oscilloscope for analysis. The oscilloscope shows both the mirror displacement (which is given by a voltage) and the light detector output.
Video 3.
Aligning a Scanning Fabry-Perot Interferometer by University of South Florida (2016)
Source. Very detailed, and shows of some nice equipment and techniques.
Oxford Physics student course notes Updated +Created
Israel Updated +Created
What they are doing to the Palestinians is a tremendous injustice. Either give them citizenship, or give them a country.
The fact that the United States supports this is an incurable black mark in their moral standing that will not be forgotten for a very long time.
Synchron Updated +Created
Video 1.
Syncron explanation video by Syncron (2018)
Source.
Video 2.
Rodney & Phil Use Our Brain Computer Interface by Syncron (2022)
Source. It might be amazing for those dudes, but it still has a long way to go.
It is not possible to see stars outside of the Milky Way by naked eye Updated +Created
The Large Magellanic Cloud stands out as the brightest thing we can see from outside the Milky Way by far!
It is not possible to teach natural sciences on Wikipedia Updated +Created
Because of edit wars and encyclopedic tone requirements. See also: Wikipedia.
Sample collection Updated +Created
As you would expect, not much secret here, we just dumped a 1 liter glass bottle with a rope attached around the neck in a few different locations of the river, and pulled it out with the rope.
And, in the name of science, we even wore gloves to not contaminate the samples!
Figure 1.
Swans swimming in the river when during sample collection
. Source. Swam poo bacteria?
Figure 2.
Tying rope to bootle for river water sample collection
. Source.
Figure 3.
Dumping the bottle into the river to collect the water sample
. Source.
Figure 4.
Measuring the river water sample temperature with a mercury thermometer
. Source.
Figure 5.
Measuring the river water sample pH with a pH strip
. Source. The strip is compared with the color of a mobile app that gives the pH for a given strip color.
Figure 6.
Noting sample collection location on the water bottle
. Source.
Video 1.
Dumping the bottle into the river to collect the water sample
. Source. That was fun.
Ivy Farm Updated +Created

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