Bismuth strontium calcium copper oxide Updated +Created
Discovered in 1988, the first high-temperature superconductor which did not contain a rare-earth element.
Closed access academic journals are evil Updated +Created
You are nothing but useless leeches in the Internet age.
You must go bankrupt all of you, ASAP.
Fuck Elsevier, fuck Springer, and fuck all the like.
Research paid with taxpayer money must be made available for free.
Researchers and reviewers all work for peanuts, while academic publishers get money for doing the work that an algorithm could do. OurBigBook.com.
When Ciro learned URLs such as www.nature.com/articles/181662a0 log you in automatically by IP, his mind blew! The level of institutionalization of this theft is off the charts! The institutionalization of theft is also clear from article prices, e.g. 32 dollars for a 5 page article.
Key physics papers from the 50's are still copyright encumbered as of 2020, see e.g. Lamb-Retherford experiment. Authors and reviewers got nothing for it. Something is wrong.
Infinite list of other people:
  • blog.machinezoo.com/public-domain-theft by Robert Važan:
    Scientific journals are perhaps one of the most damaging IP rackets. Scientists are funded by governments to do research and publish papers. Reviews of these papers are done by other publicly funded scientists. Even paper selection and formatting for publication is done by scientists. So what do journals actually do? Nearly nothing.
Video 1.
Academic Publishing by Dr. Glaucomflecken (2022)
Source.
How to hardcode subtitle into a video with FFmpeg? Updated +Created
On Ubuntu 20.10, just:
ffmpeg -i input.mp4 -vf "subtitles=subtitle.srt" output.mp4
To change font size: stackoverflow.com/questions/21363334/how-to-add-font-size-in-subtitles-in-ffmpeg-video-filter
ffmpeg -i input.mp4 -vf "subtitles=subtitle.srt:force_style='Fontsize=64'" output.mp4
The default appears to be 24, so just multiply that by whatever seems like a reasonable factor.
Note howver that .ass subtitle files can contain style information, which ffmpeg respects. Aegisub can produce and preview such styles, making .ass one of the best options.
STT_FILE Updated +Created
Entry 1 has ELF64_R_TYPE == STT_FILE. ELF64_R_TYPE is continued inside of st_info.
Byte analysis:
  • 10 8: st_name = 01000000 = character 1 in the .strtab, which until the following \0 makes hello_world.asm
    This piece of information file may be used by the linker to decide on which segment sections go: e.g. in ld linker script we write:
    segment_name :
    {
        file(section)
    }
    to pick a section from a given file.
    Most of the time however, we will just dump all sections with a given name together with:
    segment_name :
    {
        *(section)
    }
  • 10 12: st_info = 04
    Bits 0-3 = ELF64_R_TYPE = Type = 4 = STT_FILE: the main purpose of this entry is to use st_name to indicate the name of the file which generated this object file.
    Bits 4-7 = ELF64_ST_BIND = Binding = 0 = STB_LOCAL. Required value for STT_FILE.
  • 10 13: st_shndx = Symbol Table Section header Index = f1ff = SHN_ABS. Required for STT_FILE.
  • 20 0: st_value = 8x 00: required for value for STT_FILE
  • 20 8: st_size = 8x 00: no allocated size
Now from the readelf, we interpret the others quickly.
Quartz clock Updated +Created
Video 1.
How a quartz watch works by Steve Mould (2017)
Source. Mentions feedback loop loop with the quartz tuning fork for the piezoelectricity and an amplifier. Also mentions the choice of 32768 Hertz () as the first power of 2 that is outside of the human hearing range, and then how a frequency divider is used to reduce the frequency to get the second counter.
Busy beaver scale Updated +Created
The Busy beaver scale allows us to gauge the difficulty of proving certain (yet unproven!) mathematical conjectures!
To to this, people have reduced certain mathematical problems to deciding the halting problem of a specific Turing machine.
A good example is perhaps the Goldbach's conjecture. We just make a Turing machine that successively checks for each even number of it is a sum of two primes by naively looping down and trying every possible pair. Let the machine halt if the check fails. So this machine halts iff the Goldbach's conjecture is false! See also Conjecture reduction to a halting problem.
Therefore, if we were able to compute , we would be able to prove those conjectures automatically, by letting the machine run up to , and if it hadn't halted by then, we would know that it would never halt.
Of course, in practice, is generally uncomputable, so we will never know it. And furthermore, even if it were computable, it would take a lot longer than the age of the universe to compute any of it, so it would be useless.
However, philosophically speaking at least, the number of states of the equivalent Turing machine gives us a philosophical idea of the complexity of the problem.
The busy beaver scale is likely mostly useless, since we are able to prove that many non-trivial Turing machines do halt, often by reducing problems to simpler known cases. But still, it is cute.
But maybe, just maybe, reduction to Turing machine form could be useful. E.g. The Busy Beaver Challenge and other attempts to solve BB(5) have come up with large number of automated (usually parametrized up to a certain threshold) Turing machine decider programs that automatically determine if certain (often large numbers of) Turing machines run forever.
So it it not impossible that after some reduction to a standard Turing machine form, some conjecture just gets automatically brute-forced by one of the deciders, this is a path to
Dirac equation Updated +Created
Adds special relativity to the Schrödinger equation, and the following conclusions come basically as a direct consequence of this!
Experiments not explained: those that quantum electrodynamics explains like:
See also: Dirac equation vs quantum electrodynamics.
The Dirac equation is a set of 4 partial differential equations on 4 complex valued wave functions. The full explicit form in Planck units is shown e.g. in Video 1. "Quantum Mechanics 12a - Dirac Equation I by ViaScience (2015)" at youtu.be/OCuaBmAzqek?t=1010:
Then as done at physics.stackexchange.com/questions/32422/qm-without-complex-numbers/557600#557600 from why are complex numbers used in the Schrodinger equation?, we could further split those equations up into a system of 8 equations on 8 real-valued functions.
Video 1.
Quantum Mechanics 12a - Dirac Equation I by ViaScience (2015)
Source.
Video 2.
PHYS 485 Lecture 14: The Dirac Equation by Roger Moore (2016)
Source.
Superconductivity is a a form of superfluidity Updated +Created
We know that superfluidity happens more easily in bosons, and so electrons joins in Cooper pairs to form bosons, making a superfluid of Cooper pairs!
Isn't that awesome!
OurBigBook Library tested on PostgreSQL Updated +Created
After something broke on the website due to SQLite vs PostgreSQL inconsistencies and took me a day to figure it out, I finally decided to update the test system so that OURBIGBOOK_POSTGRES=true npm test will run the tests on PostgreSQL.
Originally, these were being run only on SQLite, which is the major use case for OurBigBook CLI, which came before the website.
But the website runs on PostgreSQL, so it is fundamental to test things in PostgreSQL as well.
E-learning Updated +Created
Gamma ray Updated +Created
Most commonly known as a byproduct radioactive decay.
Their energy is very high compared example to more common radiation such as visible spectrum, and there is a neat reason for that: it's because the strong force that binds nuclei is strong so transitions lead to large energy changes.
A decay scheme such as Figure "caesium-137 decay scheme" illustrates well how gamma radiation happens as a byproduct of radioactive decay due to the existence of nuclear isomer.
Gamma rays are pretty cool as they give us insight into the energy levels/different configurations of the nucleus.
They have also been used as early sources of high energy particles for particle physics experiments before the development of particle accelerators, serving a similar purpose to cosmic rays in those early days.
But gamma rays they were more convenient in some cases because you could more easily manage them inside a laboratory rather than have to go climb some bloody mountain or a balloon.
The positron for example was first observed on cosmic rays, but better confirmed in gamma ray experiments by Carl David Anderson.
Beeching cuts Updated +Created
A disaster. More cars and less trains...
Bibliograpy:
  • Losing Track by Channel 4 (1984), especially episode 5
  • www.theguardian.com/uk/2013/mar/02/beeching-wrong-about-britains-railways
    Today the makeup of UK transport looks very different from the one envisaged by Dr Beeching. Rail passenger figures have almost doubled over the past 10 years; commuter trains are crammed; young people are deserting the car for the train; and Britain's railway bosses are struggling to meet soaring demands for seats. The legacy of Beeching - dug-up lines, sold-off track beds and demolished bridges - has only hindered plans to revitalise the network, revealing the dangers of having a single, inflexible vision when planning infrastructure.
    "The crucial lesson to take from the Beeching anniversary is that you have to be flexible when planning transport infrastructure. Beeching was not," says Colin Divall, professor of rail history at York University. "Yes, many loss-making lines did need closing down, but nowhere near the number earmarked by Beeching, as we can now see with terrible hindsight."
TransferWise Updated +Created
This is a good company, first they truly helped reduce international transfer fees. They they continued to morph into a decent challenger bank.
Their Wise Interest account was amazing as of late 2023: wise.com/gb/interest/
Instant access with representative national interests and 0.29% fees.
Brick and mortar banks were way way behind in that regard!
E.g. October 2023, Wise was doing 4.87% interest after fees, while Barclay's best option was 1.16% above 5k pounds on the Rainy Day Saver (5% below). Ridiculous!
Not work Updated +Created
I caught and overcame a minor addiction to Cataclysm: Dark Days Ahead.
It does bring back the The Sims feeling from my teenage years, but with killer zombies added in.
I especially like going to sleep in that game, and how you need to setup a confy bed for it.
Some further comments at: Section "Cataclysm: Dark Days Ahead".
The way to quit is simple: delete your saves, then get annoyed with slowness of progressing back up, then use built-in debug/cheat menu to overcome that, then it's not fun anymore. This is a major advantage of single player open source games: addiction resistance!
JCVI-syn3A Updated +Created
essential metabolism for a minimal cell (2019) mentions:
JCVI-syn3A, a robust minimal cell with a 543 kbp genome and 493 genes, provides a versatile platform to study the basics of life.
Based on JCVI-syn3.0, they've added a few genes back to give better phenotypes, including slightly faster duplication time. Because the development cycle time is your God is also true in biology.
As of essential metabolism for a minimal cell (2019) it had only 91 genes of unknown function! So funny.
Bibliograpy:
Figure 1. Source. A description is present at: cdn.rcsb.org/pdb101/goodsell/2022_JCVI-syn3A.pdf Integrative Illustration of a JCVI-syn3A Minimal Cell by David Goodsell (2022) which describes everything in the picture.
Bell Labs Holmdel Complex Updated +Created
101 Crawfords Corner Rd Holmdel, NJ 07733 USA
It started with radio research apparently, including Karl Guthe Jansky.
They had a smaller building first: youtu.be/BPq_ZyOvbsg?t=51 and in 1962 opened the large new building.
Video 1.
Holmdel 20th Anniversary by AT&T Tech Channel (1982)
Source.
Video 2.
N.J.’s historic Bell Labs complex brought back to life as Bell Works by nj.com (2022)
Source. Shows the renewed building after the Bell Labs Holmdel Complex closure.
Executable hd Updated +Created
Running:
hd hello_world.out
gives:
00000000  7f 45 4c 46 02 01 01 00  00 00 00 00 00 00 00 00  |.ELF............|
00000010  02 00 3e 00 01 00 00 00  b0 00 40 00 00 00 00 00  |..>.......@.....|
00000020  40 00 00 00 00 00 00 00  10 01 00 00 00 00 00 00  |@...............|
00000030  00 00 00 00 40 00 38 00  02 00 40 00 06 00 03 00  |....@.8...@.....|
00000040  01 00 00 00 05 00 00 00  00 00 00 00 00 00 00 00  |................|
00000050  00 00 40 00 00 00 00 00  00 00 40 00 00 00 00 00  |..@.......@.....|
00000060  d7 00 00 00 00 00 00 00  d7 00 00 00 00 00 00 00  |................|
00000070  00 00 20 00 00 00 00 00  01 00 00 00 06 00 00 00  |.. .............|
00000080  d8 00 00 00 00 00 00 00  d8 00 60 00 00 00 00 00  |..........`.....|
00000090  d8 00 60 00 00 00 00 00  0d 00 00 00 00 00 00 00  |..`.............|
000000a0  0d 00 00 00 00 00 00 00  00 00 20 00 00 00 00 00  |.......... .....|
000000b0  b8 01 00 00 00 bf 01 00  00 00 48 be d8 00 60 00  |..........H...`.|
000000c0  00 00 00 00 ba 0d 00 00  00 0f 05 b8 3c 00 00 00  |............<...|
000000d0  bf 00 00 00 00 0f 05 00  48 65 6c 6c 6f 20 77 6f  |........Hello wo|
000000e0  72 6c 64 21 0a 00 2e 73  79 6d 74 61 62 00 2e 73  |rld!...symtab..s|
000000f0  74 72 74 61 62 00 2e 73  68 73 74 72 74 61 62 00  |trtab..shstrtab.|
00000100  2e 74 65 78 74 00 2e 64  61 74 61 00 00 00 00 00  |.text..data.....|
00000110  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
00000150  1b 00 00 00 01 00 00 00  06 00 00 00 00 00 00 00  |................|
00000160  b0 00 40 00 00 00 00 00  b0 00 00 00 00 00 00 00  |..@.............|
00000170  27 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |'...............|
00000180  10 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000190  21 00 00 00 01 00 00 00  03 00 00 00 00 00 00 00  |!...............|
000001a0  d8 00 60 00 00 00 00 00  d8 00 00 00 00 00 00 00  |..`.............|
000001b0  0d 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000001c0  04 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000001d0  11 00 00 00 03 00 00 00  00 00 00 00 00 00 00 00  |................|
000001e0  00 00 00 00 00 00 00 00  e5 00 00 00 00 00 00 00  |................|
000001f0  27 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |'...............|
00000200  01 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000210  01 00 00 00 02 00 00 00  00 00 00 00 00 00 00 00  |................|
00000220  00 00 00 00 00 00 00 00  90 02 00 00 00 00 00 00  |................|
00000230  08 01 00 00 00 00 00 00  05 00 00 00 07 00 00 00  |................|
00000240  08 00 00 00 00 00 00 00  18 00 00 00 00 00 00 00  |................|
00000250  09 00 00 00 03 00 00 00  00 00 00 00 00 00 00 00  |................|
00000260  00 00 00 00 00 00 00 00  98 03 00 00 00 00 00 00  |................|
00000270  4c 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |L...............|
00000280  01 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000290  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000002a0  00 00 00 00 00 00 00 00  00 00 00 00 03 00 01 00  |................|
000002b0  b0 00 40 00 00 00 00 00  00 00 00 00 00 00 00 00  |..@.............|
000002c0  00 00 00 00 03 00 02 00  d8 00 60 00 00 00 00 00  |..........`.....|
000002d0  00 00 00 00 00 00 00 00  01 00 00 00 04 00 f1 ff  |................|
000002e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
000002f0  11 00 00 00 00 00 02 00  d8 00 60 00 00 00 00 00  |..........`.....|
00000300  00 00 00 00 00 00 00 00  1d 00 00 00 00 00 f1 ff  |................|
00000310  0d 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000320  00 00 00 00 04 00 f1 ff  00 00 00 00 00 00 00 00  |................|
00000330  00 00 00 00 00 00 00 00  2d 00 00 00 10 00 01 00  |........-.......|
00000340  b0 00 40 00 00 00 00 00  00 00 00 00 00 00 00 00  |..@.............|
00000350  34 00 00 00 10 00 02 00  e5 00 60 00 00 00 00 00  |4.........`.....|
00000360  00 00 00 00 00 00 00 00  40 00 00 00 10 00 02 00  |........@.......|
00000370  e5 00 60 00 00 00 00 00  00 00 00 00 00 00 00 00  |..`.............|
00000380  47 00 00 00 10 00 02 00  e8 00 60 00 00 00 00 00  |G.........`.....|
00000390  00 00 00 00 00 00 00 00  00 68 65 6c 6c 6f 5f 77  |.........hello_w|
000003a0  6f 72 6c 64 2e 61 73 6d  00 68 65 6c 6c 6f 5f 77  |orld.asm.hello_w|
000003b0  6f 72 6c 64 00 68 65 6c  6c 6f 5f 77 6f 72 6c 64  |orld.hello_world|
000003c0  5f 6c 65 6e 00 5f 73 74  61 72 74 00 5f 5f 62 73  |_len._start.__bs|
000003d0  73 5f 73 74 61 72 74 00  5f 65 64 61 74 61 00 5f  |s_start._edata._|
000003e0  65 6e 64 00                                       |end.|
000003e4
OXAM Updated +Created
This is apparently where past exam papers can be found. Paywalled of course.
The paywall is stupid however, as they seem to provide past papers upon request, e.g.
This adds to the mess of having a different location for material per department. Presumably this exists because the central university authority wants to centralize examinations to have better control over degree requirements. If only they would also do the same for all materials and end the mess.
AGI research entity Updated +Created

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