How to report Ubuntu crashes Updated 2025-07-16
Their crash system does not have an amazing user interface.
Tested on Ubuntu 21.10.
After something crashes, look under /var/crash for a crash file, which helps to determine which package to report under on Launchpad.
E.g. a file /var/crash/_usr_sbin_gdm3.0.crash makes you want to file the bug under gdm at: bugs.launchpad.net/ubuntu/+source/gdm/+filebug
Then, while reporting the bug, you want to give the developpers access to that .crash file. But you can't publicly upload it because it contains memory dumps and could contain secret information. The way to do it is to look at the ID under:
sudo cat /var/crash/_usr_sbin_gdm3.0.uploaded
Ubuntu's crash report system has already uploaded the .crash for you, so you just have to confirm it and give the ID on the ticket.
You can view a list of all your uploaded errors at:
xdg-open https://errors.ubuntu.com/user/$(sudo cat /var/lib/whoopsie/whoopsie-id)
and each of those contain a link to:
https://errors.ubuntu.com/oops/<.uloaded error id>
which you yourself cannot see.
Running:
sudo apport-unpack /var/crash/_usr_sbin_gdm3.0.crash /tmp/app
splits it up into a few files, but does not make any major improvements.
apport-retrace
sudo apt install apport-retrace
sudo chmod 666 /var/crash/_usr_sbin_gdm3.0.crash
apport-retrace -g /var/crash/_usr_sbin_gdm3.0.crash
opens GDB with the core dump. Debug symbols are supplied as separate packages, which is a really cool idea: so you should be able to download them after the crash to see symbols. askubuntu.com/questions/487222/how-to-install-debug-symbols-for-installed-packages mentions how to install them. Official docs at: wiki.ubuntu.com/DebuggingProgramCrash#Debug_Symbol_Packages
Tried:
echo "deb http://ddebs.ubuntu.com $(lsb_release -cs) main restricted universe multiverse" | sudo tee -a /etc/apt/sources.list.d/ddebs.list
echo -e "deb http://ddebs.ubuntu.com $(lsb_release -cs)-updates main restricted universe multiverse\ndeb http://ddebs.ubuntu.com $(lsb_release -cs)-proposed main restricted universe multiverse" | sudo tee -a /etc/apt/sources.list.d/ddebs.list
sudo apt install ubuntu-dbgsym-keyring
but then sudo apt update fails with:
E: The repository 'http://ddebs.ubuntu.com impish-security Release' does not have a Release file.
Speed of light experiment Updated 2025-07-16
Video 1.
Replicating the Fizeau Apparatus by AlphaPhoenix (2018)
Source. Modern reconstruction with a laser and digital camera.
Video 2.
Visualizing video at the speed of light - one trillion frames per second by MIT (2011)
Source. Fast cameras. OK, this takes it to the next level.
The only thing that matters is that students aim towards the goals described at explain how to make money with the lesson.
Any "homework for which the student cannot use existing resources available online" is a waste of time.
The ideal way to go about it is to reach some intermediate milestone, and then document it. You don't have to do the hole thing! Just go until your patience with it runs out. But while you are doing it, go as deep and wide as you possibly can, without mercy.
The Moonshots in Education project also has a fantastic related quote:
Real World Work. Students must produce learning projects with real world applications and an authentic audience.
People will be more interested if they see how the stuff they are learning is useful.
Useful 99% of the time means you can make money with it.
Achieving novel results for science, or charitable goals (e.g. creating novel tutorials) are also equaly valid. Note that those also imply you being able to make a living out of something, just that you will be getting donations and not become infinitey rich. and that is fine.
Projects don't need of course to reach the level of novel result. But they must at least aim at moving towards that.
This is one of the greatest challenges of education, since a huge part of the useful information is locked under enterprise or military secrecy, or even open academic incomprehensibility, making it nearly to impossible for the front-line educators to actually find and teach real use cases.
Grouping by age as done in traditional education as of 2020 is useless.
Rather, we should group students by subject of interest; e.g. natural sciences, social sciences, a sport, etc., just like in any working adult organization!
This way, younger students can actually actively learn from and collaborate with older students about, see notably Jacques Monod's you can learn more from older students than from faculty.
This becomes even more natural when you try to give students must have a flexible choice of what to learn.
This age distinction should be abolished at all stages of the system, not only within K-12, but also across K-12, undergraduate education and postgraduate education.
This idea is part of the ideal that the learning environment should be more like a dojo environment (AKA peer tutoring, see also dojo learning model), rather than an amorphous checkbox ticking exercise in bureaucracy so that "everyone is educated".
Perhaps, even more importantly, is that we should put much more emphasis on grouping students with other students online, where we can select similar interest amongst the entire population and not just on a per-local-neighbourhood basis.
Don't set goals for your students.
Ask students what they want to do, and help them achieve that goal.
If they don't know what to do, give suggestions of interesting things they could do.
Once they have a goal, just help them learn everything that is needed to achieve that goal
If they don't have a goal, any attempt to learn is a total and complete waste of time.
This is because the universe of potentially useful things that can be learnt is infinite, and no human can ever learn everything.
The only solution, is to try and learn only what seems necessary to reach your goal, and just try to reach your goal instead.
This approach is called backward design.
"Graduating" and "getting a diploma" are not valid goals, because they are useless. A goal has to be either an amazing specific technological or artistic development.
23andMe Updated 2025-07-16
3D AI game Updated 2025-07-16
Video 1.
Nvidia's little fighter character (2023)
. Source.

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