It is rare to find a project with such a ridiculously high importance over funding ratio.
E.g., as of 2020, their help login help.openstreetmap.org/ shows MyOpenID as an option, which was discontinued in 2014, and not Google OAuth.
They do still seem to have a bit more activity than gis.stackexchange.com/questions/tagged/openstreetmap on Stack Exchange.
Complaints:
- Transliteration is off by default!...... wiki.openstreetmap.org/wiki/Translation You just have to learn all scripts ever. Good luck with the Chinese characters. Genius.
- In order to see information about places, you have to click "Query features" on the toolbar first. Who made such a terrible UI? Direct click is a much, and so easy to implement?
- It is impossible to discern different types of paths and other walking path symbols, the symbols are too small, and just scale down to a line no matter how much you zoom in.
- Power lines are way too visible. While that is kind of cool, it is useless and distracting to most people most of the time.
- No street-level imagery...: help.openstreetmap.org/questions/1178/adding-photos
- No aerial imagery: help.openstreetmap.org/questions/6849/how-can-i-see-the-aerial-imagery-without-editing-the-map But that is kind of understandable, as that one might not be free.
- No restaurant ratings: help.openstreetmap.org/questions/64852/ratings-for-pois because it is "Subjective". OMG those people, such a huge value powerhouse wasted.Not just for restaurants, but for other things as well, e.g. sharing of good cycle circuits.
All of this is a shame, because they do have some incredible data that you cannot find easily on other maps because people just edited it up.
- www.cell.com/cell/fulltext/S0092-8674(15)00568-1 2015. Using Genome-scale Models to Predict Biological Capabilities. Edward J. O'Brien, Jonathan M. Monk, Bernhard O. Palsson.
- www.quora.com/What-are-some-good-books-on-Escherichia-Coli-E-Coli
Size: 1-2 micrometers long and about 0.25 micrometer in diameter, so:
2 * 0.5 * 0.5 * 10e-18 and thus 0.5 micrometer square.Reference strain: E. Coli K-12 MG1655.
Genome:
- 4k genes
- 5 Mbps
- www.ncbi.nlm.nih.gov/genome/167
wget ftp://ftp.ncbi.nlm.nih.gov/genomes/all/GCF/000/005/845/GCF_000005845.2_ASM584v2/GCF_000005845.2_ASM584v2_genomic.fna.gzwget -O NC_000913.3.fasta 'https://www.ncbi.nlm.nih.gov/search/api/sequence/NC_000913.3/?report=fasta'
Synthesis project: www.sciencemag.org/news/2016/08/biologists-are-close-reinventing-genetic-code-life
Omics modeling: www.ncbi.nlm.nih.gov/pmc/articles/PMC5611438/ Tools for Genomic and Transcriptomic Analysis of Microbes at Single-Cell Level Zixi Chen, Lei Chen, Weiwen Zhang.
A single exponential map is not enough to recover a simple Lie group from its algebra by 
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01Example at: Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 7 "EXPonentiation".
The Kibble balance is so precise and reproducible that it was responsible for the 2019 redefinition of the Kilogram.
It relies rely on not one, but three macroscopic quantum mechanical effects:How cool is that! As usual, the advantage of those effects is that they are discrete, and have very fixed values that don't depend either:One downside of using some quantum mechanical effects is that you have to cool everything down to 5K. But that's OK, we've got liquid helium!
- atomic spectra: basis for the caesium standard which produces precise time and frequency
- Josephson effect: basis for the Josephson voltage standard, which produces precise voltage
- quantum Hall effect: basis for the quantum Hall effect, which produces precise electrical resistance
- on the physical dimensions of any apparatus (otherwise fabrication precision would be an issue)
- small variations of temperature, magnetic field and so on
The operating principle is something along:Then, based on all this, you can determine how much the object weights.
- generate a precise frequency with a signal generator, ultimately calibrated by the Caesium standard
- use that precise frequency to generate a precise voltage with a Josephson voltage standard
- convert that precise voltage into a precise electric current by using the quantum Hall effect, which produces a very precise electrical resistance
- use that precise current to generate a precise force on the object your weighing, pushing it against gravity
- then you precisely measure both:
- local gravity with a gravimeter
- the displacement acceleration of the object with a laser setup
How We're Redefining the kg by Veritasium
. Source. The Kibble Balance, realizing the Kilogram from fundamental constants of nature by Richard Green
. Source. Presented in 2022 for a CENAM seminar, the Mexican metrology institute. The speaker is from the Canadian metrology institute- youtu.be/ZfNygYuuVAE?t=854: they don't actually use the Quantum Hall effect device during operation, they only use it to calibrate other non-quantum resistors
The Watt balance and redefining the kilogram by National Physical Laboratory
. Source. Nothing much, but fun to hear Kibble talking about his balance in beautiful English before he passed.This is what happens when you apply a DC voltage across a Josephson junction.
It is called "AC effect" because when we apply a DC voltage, it produces an alternating current on the device.
By looking at the Josephson equations, we see that a positive constant, then just increases linearly without bound.
Therefore, from the first equation:we see that the current will just vary sinusoidally between .
This meas that we can use a Josephson junction as a perfect voltage to frequency converter.
Wikipedia mentions that this frequency is , so it is very very high, so we are not able to view individual points of the sine curve separately with our instruments.
Also it is likely not going to be very useful for many practical applications in this mode.
An I-V curve can also be seen at: Figure "Electron microscope image of a Josephson junction its I-V curve".
I-V curve of the AC Josephson effect
. Source. 
Voltage is horizontal, current vertical. The vertical bar in the middle is the effect of interest: the current is going up and down very quickly between , the Josephson current of the device. Because it is too quick for the oscilloscope, we just see a solid vertical bar.
The non vertical curves at right and left are just other effects we are not interested in.
TODO what does it mean that there is no line at all near the central vertical line? What happens at those voltages?
Superconducting Transition of Josephson junction by Christina Wicker (2016)
Source. Amazing video that presumably shows the screen of a digital oscilloscope doing a voltage sweep as temperature is reduced and superconductivity is reached.
Matthew 10:16-23 Coming Persecutions, where Jesus before being persecuted warns his disciples that there is evil in the world and that they must be aware of it, all while being pure at heart:
Behold, I send you out as sheep in the midst of wolves; so be wise as serpents and innocent as doves.
Amazing self-directed learning direction:
The pupils have a parents' evening coming up but instead of their teachers giving an account of their progress, it is a "student-led conference" at which they must present a portfolio of their work, explain what they are most proud of and discuss where they need to put in more effort.
world.hey.com/gwyn/no-excuses-bc4152fb mentions that the founder was inspired by other schools: High Tech High and Expeditionary Learning.
Lots of focus on showcase student work.
The founder Gwyn ap Harri is quite dirty mouthed, which is also cool.
Ciro Santilli tried to contact them in 2021 at: twitter.com/cirosantilli/status/1448924419016036353 and on website contact form to see if we could do some project together, but no reply.
This is a family of computers. It was a big success. It appears that this was a big unification project of previous architectures. And it also gave software portability guarantees with future systems, since writing software was starting to become as expensive as the hardware itself.
Number of neurons in the human brain by Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-03-28 +Created 1970-01-01 There are unlisted articles, also show them or only show them.