Representation theory of the Lorentz group by Ciro Santilli 35 Updated +Created
Physics from Symmetry by Jakob Schwichtenberg (2015) page 66 shows one in terms of 4x4 complex matrices.
More importantly though, are the representations of the Lie algebra of the Lorentz group, which are generally also just also called "Representation of the Lorentz group" since you can reach the representation from the algebra via the exponential map.
Bibliography:
Git by Ciro Santilli 35 Updated +Created
Ron Maimon by Ciro Santilli 35 Updated +Created
Ron Maimon is a male human theoretical physicist with an all but dissertation started in 1995 at Cornell University[ref][ref].
Figure 1.
Ron Maimon's Physics Stack Exchange profile picture
. Source.
Ron is mostly known for simultaneously:
Ron seems to share a few philosophies which Ciro greatly agrees with as part of Cirism, which together with his knowledge of physics, make Ciro greatly respect Ron. Such philosophies include:
However he also subscribes to some theories which Ciro Santilli considers conspiracy theories, e.g. his ideas about the Boston Marathon bombing that got him banned from Quora (a ban which Ciro strongly opposes due to freedom of speech concerns!), but the physics might be sound, Ciro Santilli does not know enough physics to judge, but it often feels that what he says makes sense.
chat.stackexchange.com/transcript/message/7104585#7104585 mentions that he was at Cornell University and did all but dissertation, but he mentions that he was still self-taught:
Eugene Seidel: On your personal info page you write that you are not a physics Ph.D. but does that mean you were a physics undergrad in college then went to grad school and finished ABD... or are you entirely self taught?
Ron Maimon: ABD. I am self- taught though, I only went to school for accreditation. I had a thesis worth of work at the time I left grad-school,
Eugene Seidel: ok thanks
Ron Maimon: I was just kind of sickened by academic stuff that was going on--- large extra dimensions were popular then.
Eric Walker: Anyway, thanks Ron -- I'll get back to you with more questions soon, I'm sure.
Ron Maimon: Also I was at Cornell, my advisor left for Cincinnatti, and I was not in very good standing there (I was kind of a jerk, as I still am). Some friends wanted to start a biotech company called "Gene Network Sciences", and I joined them.
This is corroborated e.g. at: web.archive.org/web/20201226171231/http://pages.physics.cornell.edu/~gtoombes/Student_Index.html (original pages.physics.cornell.edu/~gtoombes/Student_Index.html down as of 2023).
At youtu.be/ObXbKbpkSjQ?t=2454 from Video 1. "Ron Maimon interview with Jeff Meverson (2014)" he mentions his brother is a professor. At physics.stackexchange.com/questions/32382/could-we-build-a-supercomputer-out-of-wires-and-switches-instead-of-a-microchip confirms that his brother's name is "Gaby Maimon", so this neuroscience professor at the Rockerfeller University is likely him: www.rockefeller.edu/our-scientists/heads-of-laboratories/985-gaby-maimon/. Looks, age, location and research interest match.
Bibliography:
  • gmachine1729.livejournal.com/161418.html Ron Maimon answers about physics and math on Quora (part 1) by Sheng Li (2020) contains a selection of some amazing Ron Maimon posts
  • www.reddit.com/r/RonMaimon/ someone made a Reddit for him. Less than 100 users as of 2022, but has potential.
  • some Quora threads about him, oh the irony:
    • www.quora.com/Is-Ron-Maimon-actually-a-pioneer-or-a-jest
    • www.quora.com/Are-Ron-Maimons-answers-on-mathematics-physics-and-computer-science-factually-correct
    • www.quora.com/What-do-people-think-of-Ron-Maimons-paper-Computational-Theory-of-Biological-Function-I
    • www.quora.com/Who-is-Ron-Maimon/answer/Ron-Maimon
      I'm a physics grad school drop-out working in theoretical biology but I still do physics when I get a chance, but not right now because I am in a middle of a project to understand the properties of a certain virus as completely as possible.
      Also in a comment he explains something to a now deleted comment, presumably asking why he dropped out of grad school, and gives a lot more insight:
      It's a complicated boring story.
      I dropped out mainly to do biology with friends at a startup, because I figured out how you're supposed to do theory in biology, but also I truly believe it was next to impossible for me to get a degree without selling out, and I would rather be shot than write a paper with an idea I don't believe.
      My grad school phase was a disaster. I first worked for Eric Siggia, but I got away because he had me do something boring and safe, I figured I have only a limited number of years before I turn 30 and my brain rots, and I wasn't going to sell out and do second-rate stuff. I found a young guy at the department doing interesting things (Siggia was also doing interesting things, like RNA interactions, he just wouldn't assign any of them to ME), this was Philip Argyres, and got him to take me. Argyres wanted me to work on large-extra dimensions (this was 1998), but I made it clear to him that I would rather be boiled in oil. I worked a little bit on a crappy experimental setup that didn't work at all, because I didn't know enough about electromagnetic screening nor about how to set up experiment. But EVERYONE LOVED IT! This is also how I knew it was shit. Good work is when everyone hates it. But I learned Lifschitz's ideas for quantum electrodynamics in media from this project.
      Me and every competent young person in high-energy physics knew large extra dimensions was a fraud on the day it came out, and I had no intention of doing anything except killing the theory. Once Wikipedia appeared, I did my best to kill it by exposing it's charlatanry on the page for large extra dimension. That was in 2005 (after getting fired from the company), and from this point onward large-extra-dimensions lost steam. But I can't tell how much of this was my doing.
      Argyres liked N=2 theory, and we did something minor in N=2 SUSY models around 2000, but I was bogged down here, because I was trying to do Nicolai map for these, and it ALMOST worked for years, but it never quite worked. But I knew from the moduli interpretation and Seiberg-Witten solution that it must work. If I live long enough, I'll figure it out, I am still sure it isn't hard. But this was the link to statistical stochastic models, the work I was doing with Jennifer Schwarz, and I wanted to link up the two bodies of work (they naturally do through Nicolai map).
      But I had my own discovery, the first real discovery I made, in 1999, this thing that I called the mass-charge inequality, what Vafa and Motl called "the weakest-force principle" when they discovered it in 2006. It was swampland, and Vafa hadn't yet begun swampland. My advisor didn't believe my result was correct, because he saw me say many stupid things before this. So he wouldn't write it or develop it with me (but I had read about Veltman telling 'tHooft he couldn't publish the beta-function, I knew Argyres was wrong about this)
      Anyway, Argyres left for Cincinnatti in 2000, and I joined the company then. I was in the company until january 2005. Then they fired me, which was ok, by then it was a miserable hell-hole full of business types.
      I discovered Wikipedia, and started killing large extra dimensions. I wanted to finish my thesis, and some people agreed to help me do this, but I had told myself "no thesis until you get the Nicolai map sorted out" and I never did. I worked with Chris Henley a little bit, who wanted me to do some stuff for him, and I discovered an interesting model for high-Tc, but Henley said it was out of fasion, and nobody would care, even though I knew it was the key to the phenomenon (still unpublished, but soon).
      This was 2008-2009, and I became obsessed with cold fusion, so Henley dropped me, as I had clearly gone crazy. I developed the theory of cold fusion during the last weeks of working for Henley. Then I dropped out for good.
      Honestly, by the time I was gone, I realized that the internet would make a degree counterproductive, because I knew I had better internet writing skills than any of the old people, I was a Usenet person. Online, the degrees and accreditation were actually a hinderance. So by this point, I secretly preferred not to have a PhD, because I knew I was good at physics, and I could attack from the outside and win. It's not too hard if you know the technical material.
      The only problem is that I was unemployed and isolated in Ithaca for about 7 years after having gone through my first productive phase. But I developed the cold-fusion ideas in this period, I learned a lot of mathematics, and I developed a ton of biology ideas that are mostly unpublished, but will be published soon. It astonished people that I could have no degree and be unemployed and have such a sky-high ego. The reason is that I could evaluate my own stuff, and I liked it!
Backlinks:
Video 1.
Ron Maimon interview with Jeff Meverson (2014)
Source. Ripped from Jeff's "Quoracast": player.fm/series/quoracast-podcast/ron-maimon-truther Ron mentions he was an early-Usenet user. Key points:
C (programming language) by Ciro Santilli 35 Updated +Created
It gets the job done, but cannot make a large codebase DRY without insanity.
As of 2020, C is like Latin, and we are in the Middle Ages, where it has become a lingua franca.
It is interesting to note how late C appeared: 1972, compared e.g. to Fortran which is from 1957. This is basically because C was a "systems programming language", i.e. with focus on pointer manipulation, and because early computers were so weak, there was no operating system or many software layers in the early days. Fortran however was a numerical language, and it ran directly on bare metal, an application that existed before systems programming.
Examples under c.
Haskell by Ciro Santilli 35 Updated +Created
There are only two pre-requisites to using Haskell in 2020. You have to be an idealist. And you have to be a genius:
Ruby (programming language) by Ciro Santilli 35 Updated +Created
Little Boy by Ciro Santilli 35 Updated +Created
Uranium-based, dropped on Hiroshima. The uranium was enriched at the Clinton Engineer Works.
RISC-V by Ciro Santilli 35 Updated +Created
The leading no-royalties options as of 2020.
China has been a major RISC-V potential user in the late 2010s, since the country is trying to increase its semiconductor industry independence, especially given economic sanctions imposed by the USA.
E.g. a result of this, the RISC-V Foundation moved its legal headquarters to Switzerland in 2019 to try and overcome some of the sanctions.
OpenStreetMap by Ciro Santilli 35 Updated +Created
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:
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.
Escherichia coli by Ciro Santilli 35 Updated +Created
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.gz
  • wget -O NC_000913.3.fasta 'https://www.ncbi.nlm.nih.gov/search/api/sequence/NC_000913.3/?report=fasta'
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.
Light year by Ciro Santilli 35 Updated +Created
In vitro by Ciro Santilli 35 Updated +Created
B by Ciro Santilli 35 Updated +Created
H by Ciro Santilli 35 Updated +Created
N by Ciro Santilli 35 Updated +Created
S by Ciro Santilli 35 Updated +Created
Z by Ciro Santilli 35 Updated +Created
Kibble balance by Ciro Santilli 35 Updated +Created
The Kibble balance is so precise and reproducible that it was responsible for the 2019 redefinition of the Kilogram.
Figure 1.
NIST-4 Kibble balance
. Source.
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:
  • on the physical dimensions of any apparatus (otherwise fabrication precision would be an issue)
  • small variations of temperature, magnetic field and so on
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!
The operating principle is something along:
Then, based on all this, you can determine how much the object weights.
Video 1.
How We're Redefining the kg by Veritasium
. Source.
Video 2.
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
Video 3.
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.
AC Josephson effect by Ciro Santilli 35 Updated +Created
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.
Figure 1. . 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?
Video 1.
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.
Figure 2. . So it appears that there is a zero current between and . Why doesn't it show up on the oscilloscope sweeps, e.g. Video 1. "Superconducting Transition of Josephson junction by Christina Wicker (2016)"?

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