• 0 Posts
  • 48 Comments
Joined 2 years ago
cake
Cake day: October 4th, 2023

help-circle
  • The recent technology connections video cited a lot of statistics on this topic, and at least household fires are primarily caused by overcurrent, not by arcing.

    You probably know more than me — I only studied compsci with ee as minor — but from my personal experience, I’ve seen many cases where overcurrent caused damage, burns or fire, but I can’t remember a single case where arcing caused actual damage.

    Even in cheap chinesium powerstrips, the primary cause of fires is overcurrent due to AWG 22 copper clad iron wire, not arcing. (Though the switches usually weld themselves together after a few dozen uses).





  • The UK spent decades convincing everyone that all bad decisions are made by the EU and all good decisions are made by Westminster. That’s the first mistake.

    If the UK had properly educated its citizens about what the EU actually was and did, no remain campaign would’ve been necessary whatsoever. But it was politically convenient to have a scapegoat.

    And let’s be honest, remain aka “remoaners” had a ton of arguments all the time. But brexiteers just wanted to enter the magical land where the UK still mattered and they’d eat their cake and have it still.




  • Most fusion attempts try to keep a continuous reaction ongoing.

    Tokamak reactors, like JET or ITER do this through a changing magnetic field, which would allow a reaction to keep going for minutes, the goal is somewhere around 10-30min.

    Stellerator reactors try to do the same through a closed loop, basically a Möbius band of plasma encircled by magnets. The stellerator topology of Wendelstein 7-X was used as VFX for the closed time loop in Endgame. This complex topology allows the reaction to continue forever. Wendelstein 7-X has managed to keep its reaction for half an hour already.

    The NIF is different. It doesn’t try to create a long, ongoing, controlled reaction. It tries to create a nuclear chain reaction for a tiny fraction of a millisecond. Basically a fusion bomb the size of a grain of rice.

    The “promise” is that if one were to just repeat this explosion again and again and again, you’d also have something that would almost continually produce energy.

    But so far, the NIF has primarily focused on getting as much data as possible about how the first millisecond of a fusion reaction proceeds. The different ways to trigger it, and how it affects the reaction.

    The US hasn’t done large scale nuclear testing in decades. Almost everything is now happening in simulations. But the first few milliseconds of the ignition are still impossible to accurately model in a computer. To build a more reliable and stronger bomb, one would need to test the initial part of a fusion reaction in the real world repeatedly.

    And that’s where the NIF comes in.


  • If you actually calculate the maximum speed at which information can travel before causing paradoxes, in some situations it could safely exceed c.

    For two observers who are not in motion relative to each other, information could be transmitted instantly, regardless of the distance, without causing a paradox.

    The faster the observers are traveling relatively to each other, the slower information would have to travel to avoid causing paradoxes.

    More interestingly, this maximum paradox-free speed correlates with the time and space dilation caused by the observers’ motion.

    From your own reference frame, another person is moving at a speed of v*c. The maximum speed at which you could send a message to that observer, without causing a paradox, looks something like c/sqrt(v) (very simplified).