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My pi won't phone home, Echo constantly does.


That's absolutely correct.

My Echo devices go further, and can even provide a slice of Internet for the Alexa-enabled TVs that my neighbors may think have no network connection.

...and I'm OK with all of this. :)



KSP doesn't actually do > 2 body simulations allowing the paths to follow closed form solutions. This is why you have an abrupt orbit change between bodies instead of just a freeform path. There is a mod "Principia" which adds this functionality in but bewarned it makes the game very different to play!


Principia is extremely impressive, they document all their math here: https://github.com/mockingbirdnest/Principia/tree/master/doc...

One interesting detail is that the source code makes extensive use of non-ASCII identifiers, for mathematical symbols and for the names of mathematicians. One of the two primary contributors is also an active contributor to Unicode


Thanks, I was wondering how feasible this was / how one would do that in C++ !


KSP even while simplified is so amazing.

I've never gotten very far but the one thing it did manage to impress extremely thoroughly on me is "space is hard". And it's like 5x easier in KSP than on earth lol.

Also it showed me that that ever recurring thought of "why don't they just..." is usually pretty misguided.

I really respect how they managed to make this fun and so incredibly educational at the same time.


That one's good! For an alternate perspective, check episodes 0028 and 0027 of The Dangerous History Podcast (1)

1. https://profcj.org/


I'd love to watch a truck put on its' own chains, or deal with any number of situations our truckers deal with on a regular basis. Truth is, self-driving vehicles will only be feasible for the last mile, backing, parking, or fair weather interstate cruising.


> I'd love to watch a truck put on its' own chains

Here you go: https://www.youtube.com/watch?v=aEMT7D7O-ts

Okay, maybe not technically put on, but perhaps you don't actually need a faster horse?


My school bus in a ski town had these back in 2004


Even if they only solve fair weather interstate cruising, that's the bulk of the time a truck spends on the road.


Fair weather interstate cruising so that truckers can get some sleep is pretty valuable.


I imagine a first generation self driving truck would have very low threshold for unsafe driving conditions. Fog, rain, snow, whatever. Easier to wait it out or let a human drive.

Southwestern US has pretty robustly good weather and covers a large percentage of the population. Coincidentally, the biggest port in the country is in LA. Anything that can distribute cargo from there to another hub is feasible.

I do not think it is on anyone's roadmap for there to be, "Ice Road Truckers: AI Edition"



Did you know, antimatter is just time-reversed matter?

So where did all our antimatter go… ?

Yes, this ties into this.


No, it's not just time-reversal; it's charge, parity and time reversal. You can't just time-reverse an electron neutrino and obtain an electron anti-neutrino, because the parity will be wrong, and so will the weak isospin charge and lepton number ("lepton charge").

https://en.wikipedia.org/wiki/CPT_symmetry

Worse, the symmetries of the Standard Model are pretty complicated, especially when one goes from the local Lorentz or Poincaré symmetries x SU(3) x SU(2) x U(1) to the global continuous symmetries that capture https://en.wikipedia.org/wiki/Custodial_symmetry, (particlularly QCD) flavour symmetry, and scale symmetry. There are some further long-range approximate symmetries too, and those get worse with spacetime curvature. These all may have to be accounted for if one is time-reversing a region of the spacetime-filling fields of the Standard Model.

> So where did all our antimatter go?

Good question. Nobody can really tell you right now. Maybe there are galaxy clusters totally dominated by antimatter, maybe the antimatter is in a different Hubble volume, maybe it all annihilated into the cosmic microwave background and other ultra-low-energy relic fields (e.g. the cosmic (anti-)neutrino background) we haven't detected or discovered yet, maybe into primordial black holes, maybe in an extension of the Standard model to extremely high energies there isn't a matter-antimatter balance in the first place. One can write down an enormous number of different theories, and relax knowing that there is presently no evidence to favour or disfavour it, provided it's compatible with the experimental and astrophysical evidence we have today.

(I do like the idea, building on an idea arising from Wheeler's one-electron universe, that anti-electrons (in this case more than one) are screened within pion condensates ("maybe they're hiding in neutrons", vaguely), because that makes the symmetries even crazier, and particle physicists deserve that).


Hence, "c".


The universe is not split, though. You just perceive it that way. Think of it as a wave function, where some of the time, some waves cancel each other out, and are not observed, and some of the time they are amplified and easily observable.


Brother has been pretty good with ink. Even allows 3rd party.


The cloud is just someone else's computer.


CanEV Might-E Truck https://canev.com/pages/might-e-truck

Peterbilt 579EV 0-Emission Truck https://www.peterbilt.com/trucks/electric/579EV

Mean Green Electric Mowers https://meangreenproducts.com/

Freightliner eM2 0-Emission Truck https://www.freightliner.com/trucks/em2/

Mobile EV Charging Station https://www.mcharging.com/

HaiSea Wamis Electric Tug Boat https://www.seaspan.com/press-release/haisea-marine-warmly-w...

Edison Motors Hybrid Electric Truck https://www.edisonmotors.ca/


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