Ciro Santilli @cirosantilli 40

A brain orgasm.

All of them need a vacuum because you can't shoot elecrons through air, as mentioned at Video "50,000,000x Magnification by AlphaPhoenix (2022)".

News aggregators:

Personal websites:

This program did not have certain dynamic linking related sections because we linked it minimally with ld.

However, if you compile a C hello world with GCC 8.2:

some other interesting sections would appear.

For every continuous symmetry in the system (Lie group), there is a corresponding conservation law.

Furthermore, given the symmetry, we can calculate the derived conservation law, and vice versa.

As mentioned at buzzard.ups.edu/courses/2017spring/projects/schumann-lie-group-ups-434-2017.pdf, what the symmetry (Lie group) acts on (obviously?!) are the Lagrangian generalized coordinates. And from that, we immediately guess that manifolds are going to be important, because the generalized variables of the Lagrangian can trivially be Non-Euclidean geometry, e.g. the pendulum lives on an infinite cylinder.

Bought: January 2020 from store.google.com/ for 350 pounds.

Official specs: support.google.com/pixelphone/answer/7158570?hl=en&ref_topic=7530176

GMS Arena: www.gsmarena.com/google_pixel_3a-9408.php

Front camera video on Android 11: about 100MiB / minute. The encoding is however super inefficient, a FFmpeg re-encode without any options reduces it by 1/3.

For Fastboot mode: Power and Volume down simultaneously for 10-15s. It is OK if screen sleeps. On "no command", power then volume up to see options.

2026-08: same status as 2023-10, managed to get mouse to work, but I forgot the bloody PIN.

2023-10: touchscreen not registering touches anymore. Still displays images. Manage to regain access with wired USB mouse + a simple USB-C adapter. RIP. Will attempt replacement: store.ifixit.co.uk/products/google-pixel-3a-screen-genuine?variant=42388954448071, partly to get Authy access which I had never properly tested... Replaced screen, but at exact same status as before: shows image but no touch. thus I wasted my money and time (minus the learning) something else is broken.

Bought for: £159.99.

Model: XT1922-3

Type: M374B

www.gsmarena.com/motorola_moto_g6_play-9002.php Upgradable to Android 9.

2026-08: turns on to black screen: Start Up Failed: Your device didn't start up successfully.

2023-10: unable to connect to Giffgaff. "Network unavailable". Same SIM works in other phones. So annoying. Update APN to match: www.giffgaff.com/help/articles/internet-apn-settings-guide. Went next to a tower and then got signal. So the receiver is much worse than the pixel one. Vibration appears to be broken.

Authy sync worked: 2023.

Circa 2020, a bowl fell on it from about 25 cm height and broke the screen.

Generally, if something is labelled as "e-learning", it's not a good sign, as it implies that it adheres to the "teacher"/"student" separation which Ciro Santilli much despises: E-learning websites must allow students to create learning content.

Sections with sh_type == SHT_STRTAB are called string tables.

They hold a null separated array of strings.

Such sections are used by other sections when string names are to be used. The using section says:

So for example, we could have a string table containing:

The first byte must be a 0. TODO rationale?

And if another section wants to use the string d e f, they have to point to index 5 of this section (letter d).

Notable string table sections:

By default, NASM places a .symtab on the executable as well.

This is only used for debugging. Without the symbols, we are completely blind, and must reverse engineer everything.

You can strip it with objcopy, and the executable will still run. Such executables are called "stripped executables".

This book really tries to recall basic things to ensure that the reader will be able to understand the more advanced ones.

Sometimes it goes a little bit overboard, like defining what a function does several times.

But Ciro Santilli really prefers it when authors error on the side of obvious.

Used to identify organic compounds.

Seems to be based on the effects that electrons around the nuclei (shielding electrons) have on the outcome of NMR.

So it is a bit unlike MRI where you are interested in the position of certain nuclei in space (of course, these being atoms, you can't see their positions in space).

These are basically technically minded people that Ciro Santilli feels have similar interests/psychology to him, and who write too much for their own good:

Maybe one day these will also be legendary, who knows:

Another category Ciro admires are the "computational physics visualization" people, these people will go to Heaven:

Related:

Institution led:

Other mentions:

It is so mind blowing that people believed in this theory. How can you think that, when you turn on a lamp and then you see? Obviously, the lamp must be emitting something!!!

Then comes along this epic 2002 paper: pubmed.ncbi.nlm.nih.gov/12094435/ "Fundamentally misunderstanding visual perception. Adults' belief in visual emissions". TODO review methods...

Some authors use the convention of: