trelane @trelane@librem.one

Some atomic nuclei are round. Others are football-shaped. Some are even stranger. Some are pear-shaped! Some have a 'halo' of protons and neutrons orbiting a smaller core. They're all just minimizing energy - unless they're in a temporary 'excited state'. But the forces between protons and neutrons are so complex that this can make lots of things happen.

Just as noble gases are exceptionally inert because they have a filled shell of electrons, the roundest and most stable nuclei are those with a filled shell of protons - and, separately, a filled shell of neutrons. Filled shells happen when we hit a 'magic number'. The magic numbers are

2, 8, 20, 28, 50, 82, and 126.

I want to show you some cool patterns in these numbers. But first, some examples:

• Hydrogen, with just one proton, is perfectly round, but that's an exception.

• Helium-4 has 2 protons and 2 neutrons, and that's the second most common element in the universe.

• Oxygen-16 has 8 protons and 8 neutrons, and this is the most common form of oxygen.

• Calcium-40 has 20 protons and 20 neutrons, and this is the most common form of calcium. It's also the heaviest stable nucleus that has the same number of protons and neutrons! Heavier nuclei need more neutrons to be stable, but calcium-40 is stabilized by the fact that 20 is a magic number.

• Calcium-48 has 20 protons and 28 neutrons. It's not stable, because it has too many neutrons - but it has a half-life of 64 quintillion years, so it's damned close to being stable, thanks to the power of magic numbers.

• Lead-208 has 82 protons and 126 neutrons. It's the most common form of lead.

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Twenty years ago while a young grad student, I was asked to implement an experimental annealing algorithm some boffins in the U cooked up. Along the way I stumbled into one of the cleanest small-project architectures I've ever designed. On its strength, I was invited to speak at CodeCon 2006.

For its twenty-year anniversary I dusted it off & gave it serious attention for the first time in fifteen years. Way back I put a lot of work into making it as C++98 standards conformant as possible. I was pleasantly stunned how little code rot had set in. Overhauling to C++23 only took a few hours.

If you've found my political commentaries useful or my _Paranoia_ humor funny, well — it would please me a lot if you'd just take a quick look at the README.

I'm good with law and government, but I'm not proud of being good with it.

But I *am* an engineer, and I'm proud of some of my pet projects.

Drop a boost or favorite on this comment, or star/follow/fork on GitHub, if you think this kind of high-quality hackery is your bag. And as always, constructive criticism, useful bug reports, and high quality PRs are the best praise there is.

https://github.com/rjhansen/djinni

Computer science has had a bad case of identity disorder since the mid-'90s. I was in undergrad at the time and saw it take root. When I began my degree the only people taking CS were nerds: by graduation the web was beginning to take off, every company wanted to be Netscape.

In '98 I was a senior sitting in on an interview with a high school senior who openly said he wanted to study CS because his parents were insistent it would land him a good job, and computers were "fun enough," he guessed.

By '00, most of my alma mater's CS students were like that.

*There's nothing wrong with wanting a good job.* But CS is a hell of a way to get a good job. If you want to reach the serious bucks you have to have a fanatical commitment to *always* studying, because your tech skills are becoming obsolescent faster than you can learn new ones, for starters.

And if your commitment wavers, then no matter how rockstar you are now you are at most five years from being a mediocrity with an out-of-date skillset.

And the psychological toll this takes cannot be overstated, and that's on top of all the other psych tolls you have to pay.

Hot tip: if you're interested in learning the details of world sanctions against Russia, you should attend this free webinar.

I know some of the people involved. They're knowledgeable and violently allergic to bullshit.

https://instituteforfinancialintegrity.registration.goldcast.io/webinar/7a670fc9-a42e-41ec-a8d7-569c387c3f9a#Registration

Still using OpenOffice? It has unfixed security issues over a year old: https://en.wikipedia.org/wiki/Apache_OpenOffice#Security – So all users are strongly recommended to update to one of the actively maintained successor projects, like LibreOffice. (Please share and help raise awareness about this!)