IANAL, but 99% sure that the situation in Germany is that you have to identify yourself (give name, birthday, (address?)), but you /don‘t/ have to carry (or show) your government issued ID at all times.
You don't have to carry it, no. But if you don't carry your ID (or equivalent) and they have a reason to ask for it (e.g. you are a suspect of a crime), they can require you to take them wherever you keep your ID or to the station.
I figured it worked the same in the Netherlands, but from what I can tell it's true that you always need to carry it and you can get fined if you don't. So quite a bit more strict. That sucks.
I actually recently asked a German police person the exact same question if I have to have my ID/passport with me at all times.
The answer was “no, you just need to own one or the other”.
I always thought as well that there is “Ausweispflicht” (ID carrying obligatory) in Germany.
I worked through large parts of PQP ([1]) with only the prerequisites that you state, as part of a Uni course taught by Aleks Kissinger.
I got quite comfortable with the formalism and could solve most problems without too much issue, but at the end I still knew nothing at all about quantum physics. YMMV
Worth looking into any COSS (commercial open source) companies that you find interesting.
That’s where you write the code that then others glue together - plus you can inspect the codebase beforehand!
I think you are kinda right in that it might be very hard to get people out of homelessness, but what more housing could do is prevent homelessness in the first place.
Presumably most people start their lives as not homeless, and at some point that changes, because housing prices exceed their income. More housing would lead to lower housing prices and less homelessness.
Interestingly, I think that almost all of the downsides listed in the article and in the comments go away if you use a good framework for creating microservices (example for this: [0]):
No internal glue code, no overhead by writing network interfaces, no slow HTTP calls (faster gRPC instead), no manual handling of asynchronous tasks.
If you want to counteract this tendency, consider getting them into (competitive) sports. Nothing will work right away, they will have to „grind“ (train/practice) a lot, failures are all but certain; but hard work and perseverance get rewarded, and the successes are all the sweeter. As a young guy who has had a modern and easy childhood not unlike the one you describe, many of my most cherished memories come from competing in a sport.
Sports and musical instruments - if you can keep them motivated/interested, the results of focused practice can’t be ignored.
To some extent I only realized this late in life myself. I don’t play a musical instrument, schoolwork through undergraduate never required really hard work and as an athlete I was a lackluster football player who never really put in the time to get better. But as an adult, computer programming and crossword puzzles were things which I applied myself to and was astonished to see how much better I could get at them by putting in the time and effort. (That being said I am an awful teacher - as an autodidact myself, I often - unfairly - feel that others aren’t putting enough effort in.)
I travel between Italy, Austria, Germany and Switzerland somewhat regularly, not rarely passing through 3 of the 4 countries for a given trip. I use the Austrian national railway‘s (ÖBB) app to book my tickets, I get a single QR code on my phone that is valid for all legs of my journey, gets scanned by the personnel of whatever country‘s railway company, and I‘m good. Never had any problems whatsoever.
I wish the Swiss SBB app would have the same functionality. While in theory it should work the same, they just prefer to complain "no location signal" when you're outside country.
From what I can tell, the field is indeed evolving very rapidly, but I have only worked on a specific application (knowledge graph completion), so I can't give an overview over all the current day applications.
I can, however, recommend William Hamilton's excellent text book, which is available online [1].
