sterexx

sterexx t1_j2hootb wrote

Ah okay! Yeah it’s fascinating how long they’ve been able to work on this stuff without having any actual hardware. Kinda like Turing’s machine!

If you can imagine how the machine works, you can design programs for it. Shor’s algorithm, which breaks RSA and other venerable public key cryptography systems (if you had a quantum computer to run it on), was made in 1994

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sterexx t1_j2hnr7k wrote

NIST has been running a competition for quantum resistant encryption algos and somewhat recently announced some finalists for upcoming standards. They wouldn’t have any interest in ones not resistant to classical methods. If you can recall which algo you’re thinking of, though, I’d be interested to see

https://www.nist.gov/news-events/news/2022/07/nist-announces-first-four-quantum-resistant-cryptographic-algorithms

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sterexx t1_j2cp5ao wrote

That’s a great detail! I’m going to expand on it in case OP reads here

Gunpowder deflagrates instead of detonating. It burns instead of booms. Well, it does boom from our perspective, but if you watch in slow motion it takes a lot more time than dynamite. This gradually increases the gas pressure to start the bullet moving.

Bullets fit very tightly with the barrel. Imagine a tennis ball stuck tightly into the end of a pipe. You could punch it with all your strength, but it wouldn’t go very far and you’d probably damage yourself, the pipe and the ball. If you start pushing lightly and get it moving and then push harder, you’ll expend the same amount of energy and get it much farther down the pipe without damaging anything.

This is also why some calibers benefit from a longer barrel. If the bullet leaves the barrel before all the powder finishes burning, it will miss out on some velocity. Some calibers are designed to burn quickly so barrels can be short, but they also need to be designed strong to handle the higher peak pressure.

On top of all that, if the gun uses some of that recoil energy to do something useful like load another round, the impulse will be even more spread out on the shooter.

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sterexx t1_j2cm1f2 wrote

I can visualize the econ 101 graphs right now!

And this is almost too obvious to mention, but those computers aren’t exactly the same. They’re generally differentiated in at least some way, even if it’s just aesthetically.

But if we’re talking about precisely equivalent products, yeah economies of scale can get so interesting. My favorite is that Amazon can sell items at cost and still come out ahead.

Because they’re such a big (and reliable) customer to their vendors, they can get great terms on their invoices where they don’t have to pay for like a couple months after receiving their inventory.

So Amazon gets this $1000 TV in inventory but doesn’t have to pay yet. They sell it to me for $1000. They now have $1000 they can invest and earn interest on (or otherwise do whatever they want with) and don’t have to pay it back for a while

I don’t know exactly what scale they’re doing that at these days but it’s still amazing to me

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sterexx t1_j2cd3dd wrote

Reply to comment by CrayonDelicacies in Question by Psychological_Wheel2

That’s so awesome

I really enjoyed the tour of this water treatment plant in SF. It doesn’t make potable water, but the effluent looked quite nice compared to what was coming in! Stuff filtered out does get composted, so it’s still producing something useful

My (least?) favorite part though was this image with terrible implications. We’re in this huge room with big pools of sewage where they’re letting solids settle to the bottom and oils to the top. And mounted on the walls are a bunch of life preservers.

The thought still makes me shudder

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sterexx t1_j1uo18p wrote

My friend had an interesting job then at a major financial industry company. Lots of rollerblading through the offices with a radio receiver and a pair of scissors.

Around then wifi security was bad even if you did set a password (because it was probably still WEP*). Yet the convenience was too tempting for some employees. They’d bring in a router and plug it into their ethernet cable so they could have their own little rogue network in their cubicle.

So my friend would home in on these spots, cut the ethernet cable, and leave a note that they’ll be fired if caught doing this again

* Shoutout to my neighbors at the place I moved to in 2011 for still using WEP security. Our cable didn’t get set up for a week or two. Lifesaver

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sterexx t1_itp3kx5 wrote

A lot are, but a lot aren’t. Jews actually pay for the upkeep of a long wire encircling much of Manhattan so that it counts as a place they’re allowed to do certain stuff on the sabbath

They’ve got their own police-like force across the river in wburg, and other places with high concentrations of orthodox jews

and even among jews that are culturally assimilated, they maintain a much tighter social network than, say, the american great grandchildren of swedish immigrants. there are like 3 million of those and 7 million american jews. having a distinct religion will do that. lutheran swedes and germans intermixed in the midwest quite easily

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sterexx t1_irnacpb wrote

I imagine it’s a lot easier to just put a telescope in space than dock with a space station, attach it, then have to account for the station’s rotation in its own aiming, and also have a large area blocked from view due to not being able to actually turn all the way around

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