Transmission electron microscopy Updated 2025-07-16
Video 1.
Transmission Electron Microscope by LD SEF (2019)
Source. Images some gold nanopraticles 5-10 nm. You can also get crystallographic information directly on the same machine.
Helium Updated 2025-07-16
Oxygen Updated 2025-07-16
PostgreSQL Updated 2025-07-16
Had a look at the source tree, and also felt good.
If Oracle is the Microsoft of database, Postgres is the Linux, and MySQL (or more precisely MariaDB) is the FreeBSD (i.e. the one that got delayed by legal issues). Except that their software licenses were accidentally swapped.
The only problem with Postgres is its name. PostgreSQL is so unpronounceable and so untypeable that you should just call it "Postgres" like everyone else.
PostgreSQL logging Updated 2025-07-16
Ubuntu 21.10 has a certain default level of logging by default to:
/var/log/postgresql/postgresql-13-main.log
but it does not log everything, only/mostly errors it seems.
Setting:
log_statement = 'all'
under:
/etc/postgresql/13/main/postgresql.conf
and then restarting the server:
sudo service restart postgresql
just works.
Transmon Updated 2025-07-16
Used e.g. in the Sycamore processor.
The most basic type of transmon is in Ciro's ASCII art circuit diagram notation, an LC circuit e.g. as mentioned at youtu.be/cb_f9KpYipk?t=180 from Video "The transmon qubit by Leo Di Carlo (2018)":
+----------+
| Island 1 |
+----------+
   |   |
   X   C
   |   |
+----------+
| Island 2 |
+----------+
youtu.be/eZJjQGu85Ps?t=2443 from Video "Superconducting Qubits I Part 1 by Zlatko Minev (2020)" describes a (possibly simplified) physical model of it, as two superconducting metal islands linked up by a Josephson junction marked as X in the diagram as per-Ciro's ASCII art circuit diagram notation:
+-------+       +-------+
|       |       |       |
| Q_1() |---X---| Q_2() |
|       |       |       |
+-------+       +-------+
The circuit is then analogous to a LC circuit, with the islands being the capacitor. The Josephson junction functions as a non-linear inductor.
Others define it with a SQUID device instead: youtu.be/cb_f9KpYipk?t=328 from Video "The transmon qubit by Leo Di Carlo (2018)". He mentions that this allows tuning the inductive element without creating a new device.
Video 2.
Calibration of Transmon Superconducting Qubits by Stefan Titus (2021)
Source. Possibly this Keysight which would make sense.
Transsexual Updated 2025-07-16
Transversal time dilation Updated 2025-07-16
Light watch transverse to direction of motion. This case is interesting because it separates length contraction from time dilation completely.
Of course, as usual in special relativity, calling something "time dilation" leads us to mind boggling ideas of "symmetry breaking": if both frames have a light watch, how can both possibly observe the other to be time dilated?
And the answer to this, is the usual: in special relativity time and space are interwoven in a fucked up way, everything is just a spacetime event.
In this case, there are three spacetime events of interest: both clocks start at same position, your beam hits up at x=0, moving frame hits up at x>0.
Those two mentioned events are spacelike-separated events, and therefore even though they seem simultaneous to you, they are not going to be simultaneous to the moving observer!
If little clock one meter away from you tells you that at the time of some event (your light beam hit up) the moving light watch was only 50% up, this is just a number given by your one meter away watch!
Natural science Updated 2025-07-16
Ciro Santilli often wonders to himself, how much of the natural sciences can one learn in a lifetime? Certainly, a very strong basis, with concrete experimental and physics, chemistry and biology should be attainable to all? How much Ciro manages to learning and teach in those areas is a kind of success metric of Ciro's life.
Nitrogen Updated 2025-07-16
Polonium Updated 2025-07-16
Discovered by Marie Curie, published July 1999.
ProtonMail Updated 2025-07-16
One of the very few encrypted emails... beauty. And they also have an encrypted password manager!!! Using this is a must as of 2023 basically. The only missing thing now is to find a fully open source alternative!!!
Sure, search capabilities have to be somewhat limited: proton.me/blog/engineering-message-content-search
techcrunch.com/2021/09/06/protonmail-logged-ip-address-of-french-activist-after-order-by-swiss-authorities/ you've fucking got to use Tor Browser with it if you want your IP to remain hidden, learn that...
Are daily notifications without a recovery email possible? www.reddit.com/r/ProtonMail/comments/yjau8f/allow_daily_email_notifications_without_having_a/ OK, they do work actually.
The lack of Gmail dot trick is tragic however, and you have to pay for multiple aliases. But you can however create separate inboxes with the same cell phone verification however.
PsiQuantum Updated 2025-07-16
Good talk by CEO before starting the company which gives insight on what they are very likely doing: Video "Jeremy O'Brien: "Quantum Technologies" by GoogleTechTalks (2014)"
PsiQuantum appears to be particularly secretive, even more than other startups in the field.
They want to reuse classical semiconductor fabrication technologies, notably they have close ties to GlobalFoundries.
So he went to the US and raised N times more from the American military-industrial complex.
Quantum control systems use FPGAs Updated 2025-07-16
It seems that all/almost all of them do. Quite cool.
Video 1.
FPGA Architecture of the Quantum Control System by Keysight (2022)
Source. They actually have a dedicated quantum team! Cool.
Video 2.
FPGA based servo system by Atoms & Laser (2018)
Source. The Indian lady is hardcore.
Tree representation Updated 2025-07-16
This section is about ways in which you can represent a tree.
Trees are a specific type of graph, so any graph representation also provides a way to represent a tree.
Therefore this section will focus only on methods specific to tress, and which cannot be used for graphs in general.

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