• 2 Posts
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Joined 3 years ago
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Cake day: January 13th, 2022

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  • And you wouldn’t have to reverse causality to travel backwards in time. You would just have to travel faster than the speed of light.

    If you can travel faster than the speed of light then you can arrive at a destination before you left.

    I know practically nothing about all the wormhole theories, because I just don’t consider them relevant, but from a logical standpoint, the above does not feel correct to me.

    The thing is, you would arrive at your destination before the light would arrive there from where you started. So, you could take out your telescope and potentially watch your own launch.

    But that doesn’t actually put you into the past. It just looks like it when looking into the direction you came from. Light from the other direction will look like you’ve fast-forwarded through time, because you now get more recent imagery.

    I don’t have another explanation why someone might think, this might put you into the past…


  • Hmm, but why do you think these things haven’t occurred yet?

    As far as I can tell, the speed of causality means things can have occurred in a certain location in the universe, but it takes time until the effects have permeated into the rest of the universe.

    So, it’s like a shockwave from an explosion. The explosion happens, but it takes a few seconds until you feel the shockwave.
    Well, with the difference that you can see an explosion before the shockwave. When we’re at the speed of causality, literally no evidence will have arrived in your position until it does.

    So, one could go meta-philosophical with basically “If a tree falls in a forest and no one has heard it yet, did it actually already happen?”, but yeah, I don’t think that’s terribly useful here.

    And well, if we treat it like a shockwave, let’s say you detonate some TNT and step through a wormhole to somewhere 20 km away. You would know that the shockwave will arrive soon, but does that matter? The shockwave will still just continue pushing on.

    And I guess, crucially, it did already happen, so you can’t do the usual time travel paradox of preventing that it would happen.


  • That’s actually not as obvious as it might sound. The thing is, as far as we know, light seems to have no mass¹. No mass means no inertia. So, if it accelerates at all, it should immediately be at infinite speed. But for some reason, it actually doesn’t go faster than what we typically call the speed of light. And we assume, that’s the case, because that’s actually the speed of causality.

    So, it’s reversed. It’s not that light is just the fastest thing and as a consequence of that, nothing can be transmitted faster. No, it’s actually that there appears to be a genuine universal speed limit and light would be going faster, if it could.

    ¹) Light is still affected by gravity, e.g. can’t escape from black holes. We do assume that gravity is just a ‘bend in spacetime’ because of that, meaning even any massless thing are affected by it, but yeah, we’re still struggling to understand what mass actually is then.


  • Well, I’m going to give the party-pooper response, even though science fiction and pop-science love to fantasize differently:

    The past and the future are theoretical concepts. They don’t actually exist in the sense that you can ‘send’ something to them.
    Obviously, you can write data to a hard drive and then read it out after a week has passed, but presumably that is not what you had in mind.

    But that’s also the essence of the time travel that the theory of general relativity allows. You can travel forwards more slowly along the time axis by travelling more quickly on the space axis (close to the speed of light), which means you might just need to spend 5 perceived years to end up in the year 2200.
    Similarly, you could take a hard drive onto this journey and it wouldn’t have fallen apart in that time.

    Travelling back in time makes no sense in general relativity. You would need to reverse causality for that, which is on an entirely different level from merely slowing causality down.

    General relativity would mathematically allow for the existence of wormholes, but that’s pushing the theory to extremes where it might simply not be applicable to reality anymore. We certainly have no actual evidence for wormholes.



  • I watched it on my phone in 1080p60 and the scale didn’t bother me. It’s not like I have to read a lot of text and the precise position of the player character is mostly irrelevant, too. Like, if you get hit by a train or something, the screen will flash red and you’ll react to it, too, so I’ll know what’s going on.

    Well, and I don’t look at the screen at all times anyways. 🙃

    Would like to see more of this journey…




  • I’m having a hard time figuring out, if these exist elsewhere, but over here, I can buy dried soy shreds, which are really great for pasta.

    Here's a product I can buy over here, to give you an idea.

    So, those are roughly meatball-shaped. There’s also smaller one’s which kind of work in sauces like minced meat.
    They don’t taste like meat, more like wheat, but they give you the same protein and chewiness and can be kept in a cupboard basically until the end of time.




  • I’m not a lawyer, but I’d say that’s a case for implied consent.

    Typical example is when you’re shopping and you hand the cashier the money that they’re asking for, then that counts as an agreement to a contract. You don’t have to explicitly say that you’d like to buy the wares for that price.

    With the dark mode button, I’d expect the same. You’re very likely cool with them storing your preference, specifically for providing you with dark mode (not for tracking et al). So, pressing the button would presumably suffice as consent for that.


  • Hmm, interesting. Here in Germany, power companies are partially privatized and I always thought, whomever came up with that nonsense took inspiration from the turbo-capitalism in the USA. Apparently not.

    Do they need to be profitable, though, in your model? It mostly sounds like a traditional public service, where the government could just tell them to use the money for solar…