Ciro Santilli @cirosantilli 35

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Segmentation  Updated 2024-12-23  +Created 1970-01-01

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In x86 systems, there may actually be 2 address translation steps:

first segmentation
then paging

like this:

(logical) ------------------> (linear) ------------> (physical)
             segmentation                 paging

The major difference between paging and segmentation is that:

paging splits RAM into equal sized chunks called pages
segmentation splits memory into chunks of arbitrary sizes

This is the main advantage of paging, since equal sized chunks make things more manageable by reducing memory fragmentation problems. See also:

Paging came after segmentation historically, and largely replaced it for the implementation of virtual memory in modern OSs.

Paging has become so much more popular that support for segmentation was dropped in x86-64 in 64-bit mode, the main mode of operation for new software, where it only exists in compatibility mode, which emulates IA-32.

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CGI comms  Updated 2024-12-23  +Created 1970-01-01

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We've come across a few shallow and stylistically similar websites on suspicious ranges with this pattern.

No JS/JAR/SWF comms, but rather a subdomain, and an HTTPS page with .cgi extension that leads to a login page. Some names seen for this subdomain:

secure.: most common
ssl.: also common
various other more creative ones linked to the website theme itself, e.g.:
- musical-fortune.net has a backstage.musical-fortune.net

The question is, is this part of some legitimate tooling that created such patterns? And if so which? Or are they actual hits with a new comms mechanism not previously seen?

The fact that:

hits of this type are so dense in the suspicious ranges
they are so stylistically similar between on another
citizenlabs specifically mentioned a "CGI" comms method

suggests to Ciro that they are an actual hit.

In particular, the secure and ssl ones are overused, and together with some heuristics allowed us to find our first two non Reuters ranges! Section "secure subdomain search on 2013 DNS Census"

Some currently known URLs

If we could do a crawl search for secure.*com/cgi-bin/*.cgi that might be a good enough fingerprint, maybe even *.*com/cgi-bin/*.cgi. Edit: it is not perfect, but we kind of did it: Section "secure subdomain search on 2013 DNS Census".

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Minimal working example  Updated 2024-12-23  +Created 1970-01-01

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The musical study of software engineering.

Ciro Santilli is obsessed by those in order to learn any new concept, not just for bug reporting.

This includes to learn more theoretical subjects like physics and mathematics.

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Mind uploading  Updated 2024-12-23  +Created 1970-01-01

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Wikipedia defines Mind uploading as a synonym for whole brain emulation. This sounds really weird, as "mind uploading" suggests much more simply brain dumping, or perhaps reuploading a brain dump to a brain.

Superintelligence by Nick Bostrom (2014) section "Whole brain emulation" provides a reasonable setup: post mortem, take a brain, freeze it, then cut it into fine slices with a Microtome, and then inspect slices with an electron microscope after some kind of staining to determine all the synapses.

Likely implies AGI.

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Convert PDF to text  Updated 2024-12-23  +Created 1970-01-01

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Bacterial outer membrane  Updated 2024-12-23  +Created 1970-01-01

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Only present in Gram-negative bacteria.

Figure 1.
Structure of a Gram-negative bacteria
. Source.

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Spherical harmonic  Updated 2024-12-23  +Created 1970-01-01

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Correspond to the angular part of Laplace's equation in spherical coordinates after using separation of variables as shown at: en.wikipedia.org/wiki/Spherical_harmonics#Laplace's_spherical_harmonics

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Telegram (software)  Updated 2024-12-23  +Created 1970-01-01

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Not end-to-end encrypted by default, WTF... you have to create "secret chats" for that:

www.quora.com/Why-does-Telegram-not-use-end-to-end-encryption-by-default-so-that-there-are-not-keys-to-give-to-the-government

You can't sync secret chats across devices, Signal handles that perfectly by sending E2EE messages across devices:

www.reddit.com/r/Telegram/comments/7hx8vd/when_will_telegram_get_secret_chats_crossdevices/

This is a deal breaker because Ciro needs to type with his keyboard.

Desktop does not have secret chats: www.reddit.com/r/Telegram/comments/9beku1/telegram_desktop_secret_chat/ This is likey because it does not store chats locally, it just loads from server every time as of 2019: www.reddit.com/r/Telegram/comments/baqs63/where_are_chats_stored_on_telegram_desktop/ just like the web version. So it cannot have a private key.

Allows you to register a public username and not have to share phone number with contacts: telegram.org/blog/usernames-and-secret-chats-v2.

Has Reproducible builds on Android and iOS: core.telegram.org/reproducible-builds

Self deleting messages added to secret chats in Q1 2021: telegram.org/blog/autodelete-inv2

Can delete messages from the device of the person you sent it to, no matter how old.

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Mind blown  Updated 2024-12-23  +Created 1970-01-01

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A brain orgasm.

Video 1.

The Universe I, II & III | Tim and Eric Awesome Show by Adult Swim UK (2017)

Source. This amazing video contains the best mind blown meme ever, Ciro Santilli almost shat himself when he first watched it.

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503: Bitcoin over capacity  Updated 2024-12-23  +Created 1970-01-01

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Starting tx a87d406fae047258a12923b3c11a797a5765bd8f868df5c7e9b1cead0e92c9c1: the message:

503: Bitcoin over capacity!

appears about 13 thousand times. WTF happened?

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Microwave  Updated 2024-12-23  +Created 1970-01-01

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Micro means "small wavelength compared to radio waves", not micron-sized.

Microwave production and detection is incredibly important in many modern applications:

telecommunications, e.g. being used in
- Wi-Fi
- satellite communications
  youtu.be/EYovBJR6l5U?list=PL-_93BVApb58SXL-BCv4rVHL-8GuC2WGb&t=27 from CuriousMarc comments on some piece of Apollo equipment they were restoring/reversing:
  These are the boxes that brought you voice, data and live TV from the moon, and should be early masterpieces of microwave electronics, the blackest of black arts in analog electronics.
  Ah, Ciro Santilli really wishes he knew what that meant more precisely. Sounds so cool!
- 4G and other cellular network standards
radar. As an example, 1965 Nobel Prize in Physics laureate Julian Schwinger did some notable work in the area in World War II, while most other physicists went to the Manhattan Project instead.
This is well highlighted in QED and the men who made itby Silvan Schweber (1994). Designing the cavity wasn't easy. One of the key initial experiments of quantum electrodynamics, the Lamb-Retherford experiment from 1947, fundamental for modern physics, was a direct consequence of post-radar research by physicists who started to apply wartime developments to their scientific search.
Wikipedia also mentions en.wikipedia.org/w/index.php?title=Microwave&oldid=1093188913#Radar_2:
The first modern silicon and germanium diodes were developed as microwave detectors in the 1930s, and the principles of semiconductor physics learned during their development led to semiconductor electronics after the war.
microwave is the natural frequency of several important Atomic, Molecular and Optical Physics phenomena, and has been used extensively in quantum computing applications, including completely different types of quantum computer type:
- trapped ion quantum computer; Video "Trapping Ions for Quantum Computing by Diana Craik (2019)"
- superconducting quantum computer; e.g. this Junior Microwave Design Engineer job accouncement from Alice&Bob: archive.ph/wip/4wGPJ
Likely part of the appeal of microwaves is that they are non-ionizing, so you don't destroy stuff. But at the same time, they are much more compatible with atomic scale energies than radio waves, which have way way too little energy.

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Monster Raving Loony Party  Updated 2024-12-23  +Created 1970-01-01

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Video 1.

Monster Raving Loony Party Conference by Britclip

. Source.

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Mojim  Updated 2024-12-23  +Created 1970-01-01

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Leading Chinese lyrics website: mojim.com/twznew.htm

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Monotreme  Updated 2024-12-23  +Created 1970-01-01

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The weirdest mammal clade: they lay fucking eggs. Only 5 known species alive as of 2020.

Eggs are basal: they simply didn't evolve out of what other reptiles do. From which we conclude that milk came before eggs stopped.

So this is the most basal subclade of mammals.

Etymology: means "single hole" in Greek, because like other reptiles it has a single hole for shit, pee and fucking: the cloaca.

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Jeff Bezos  Updated 2024-12-23  +Created 1970-01-01

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Jeff has spoken a lot in public about Amazon, perhaps even more than other comparable founders, see e.g. Section "History of Amazon". Kudos for that.

Figure 1.
Jeff Bezos Unveiling the Blue Origin Lunar Lander
. Source.

Video 1.

Has the laugh of Jeff Bezos changed as he got rich? by Barış Aktaş (2020)

Source.

Video 2.

Order from Bulgaria by Jeff Bezos

. Source. From a 2002 talk at MIT.

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Lie algebra of

S L (2)

 Updated 2024-12-23  +Created 1970-01-01

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This is a good first concrete example of a Lie algebra. Shown at Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 4.2 "How to linearize a Lie Group" has an example.

We can use use the following parametrization of the special linear group on variables

x

y

and

z

M = [1 + x z y (1 + y z) / (1 + x)]

(1)

Every element with this parametrization has determinant 1:

d e t (M) = (1 + x) (1 + y z) / (1 + x) - y z = 1

(2)

Furthermore, any element can be reached, because by independently settting

x

y

and

z

M_{00}

M_{01}

and

M_{10}

can have any value, and once those three are set,

M_{11}

is fixed by the determinant.

To find the elements of the Lie algebra, we evaluate the derivative on each parameter at 0:

M_{x} M_{y} M_{z} = \frac{d M}{d x} ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = \frac{d M}{d y} ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = \frac{d M}{d z} ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = [10 0 - (1 + y z) / (1 + x)^{2}] ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = [00 1 z / (1 + x)] ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = [01 0 y / (1 + x)] ∣ ∣ ∣ ∣ ∣_{(x, y, z) = (0, 0, 0)} = [10 0 - 1] = [0010] = [0100]

(3)

Remembering that the Lie bracket of a matrix Lie group is really simple, we can then observe the following Lie bracket relations between them:

[M_{x}, M_{y}] [M_{x}, M_{z}] [M_{y}, M_{z}] = M_{x} M_{y} - M_{y} M_{x} = M_{x} M_{z} - M_{z} M_{x} = M_{y} M_{z} - M_{z} M_{y} = [0010] = [0 - 1 00] = [1000] - [00 - 1 0] - [0100] - [0001] = [0020] = [0 - 2 00] = [10 0 - 1] = 2 M_{y} = - 2 M_{z} = M_{x}

(4)

One key thing to note is that the specific matrices

M_{x}

M_{y}

and

M_{z}

are not really fundamental: we could easily have had different matrices if we had chosen any other parametrization of the group.

TODO confirm: however, no matter which parametrization we choose, the Lie bracket relations between the three elements would always be the same, since it is the number of elements, and the definition of the Lie bracket, that is truly fundamental.

Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 4.2 "How to linearize a Lie Group" then calculates the exponential map of the vector

x M_{x} + y M_{y} + z M_{z}

as:

I c o s h (θ) + M_{x} s i n h (θ) / θ

(5)

with:

θ^{2} = x^{2} + b c

(6)

TODO now the natural question is: can we cover the entire Lie group with this exponential? Lie Groups, Physics, and Geometry by Robert Gilmore (2008) Chapter 7 "EXPonentiation" explains why not.

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Bert Hubert  Updated 2024-12-23  +Created 1970-01-01

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Co-founder of PowerDNS, an open source dNS implementation.

Homepage: berthub.eu/ says:

I sometimes contribute to science, I care a lot about Europe, innovation, biology & health

.
All stuff Ciro cares about too! Cool dude! In particular Ciro loved his quote of I should have loved biology.

He's writing a fun-sounding book about molecular biology as of 2022: berthub.eu/dna-book. Appears to be closed source though. Ciro wonders if he really needs to sell the book for money after all those years though, rather than just publishing it online for free.

Looking at Bert just brings the Dutch Golden Age, and more in particular Antonie van Leeuwenhoek to mind. Epic.

Video 1.

How life is Digital by Bert Hubert (2021)

Source. Just a "boring" overview of the central dogma of molecular biology ;-)

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Robert O'Callahan  Updated 2024-12-23  +Created 1970-01-01

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Creator of Mozilla rr, of which Ciro Santilli is a huge fan of!

He quit Mozilla in 2016 to try and commercialize an rr extension called Pernosco.

But as of 2022, he advertised himself as part of "Google Research", so maybe that went under, sample source: archive.ph/o9622. TODO when did he start? There's apparently an unrelated homonym: www.linkedin.com/in/rob-ocallahan/

He's apparently very religious, and very New Zelandish, twitter.com/rocallahan auto-describes:

Christian. Repatriate Kiwi.Terry A. Davis and D. Richard Hipp come to mind. One is tempted to speculate a correlation even, the proportion amongst systems programmers feels so much higher than in other areas of programming! Maybe it is because you have to be a God to do it in the first place.

Video 1.

Robert O'Callahan interview by Toby Ho (2022)

Source.

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Mitochondrial phosphate carrier protein  Updated 2024-12-23  +Created 1970-01-01

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Just like the adenine nucleotide translocator moves ATP/ADP in and out, this one moves loose phosphate in.

Both of those together recycle the cellular respiration carriers from/to the mitochondria.

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Advanced Placement  Updated 2024-12-23  +Created 1970-01-01

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This is a good initiative. It doesn't go nearly as deep as it needs to go to fix students must have a flexible choice of what to learn, but it is a start!

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