this post was submitted on 13 Dec 2024
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I was watching a sausage making video, and youtube recommended this, and wow. Such a happy, positive, great!. I was intrigued

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[–] danc4498 2 points 2 days ago (1 children)

Here’s what I don’t understand. It all seems like a limitation based on the assumption that the observing ship is not moving at all. You can’t travel the speed of light relative to me because it would look like you’ve stopped accelerating.

What if the observing ship is moving half the speed of light, and the other ship is moving in the opposite direction at half the speed of light? Relative to each other, they are both traveling the speed of light now. I am definitely missing something here.

[–] [email protected] 1 points 2 days ago

My gut wants to say since the speed of light in a vacuum is constant across all reference frames, you can only make statements of speed from inertial reference frames (non accelerating) .... Noo, hrmm that doesn't work. I'm stumped, by physics isn't up to this, it's a great thought experiment

This would be a excellent question for no stupid questions! [email protected]

[–] [email protected] 9 points 4 days ago

I always though it's kinda depressing how even if we could travel close to speed of light, the time it would take to get to the nearest galaxies would still be hundreds if not thousands of years. However I recently learned that it's not quite so because when traveling at that speed you're also traveling in time, so from your perspective it wouldn't take long at all. It's just that you can't really ever come back because everyone else would be dead by then.

[–] [email protected] 6 points 5 days ago (1 children)

Unless you have a energy source that weighs next to nothing, or you somehow can decrease your mass down to next to nothing you will never go as fast or faster than light. (E=m*c² and all that jazz)

[–] [email protected] 5 points 5 days ago

Wouldn't you technically need an energy source that wouldn't increase in mass if you require more energy? The weight of the initial energy source doesn't matter, it just needs its weight to stay constant as it's energy output scales up infinitely.

Which, y'know, goes against the laws of thermodynamics.

[–] givesomefucks 5 points 5 days ago

Eh.

Physics does some weird shit based on frame of reference. Until something goes faster than the speed of light, that's the limit. If it goes back to nothing moving faster than light, it's a limit again. But that time I'm between... Maybe?

Like, we're talking about something that has a coinflips chance of being a wave or particle each time we look at it. And if no one's watching, it's somehow both. Similarly the speed of light might just be the equivalent of draw distance. And just like Rick glitched out that weird alien simulation, maybe we can glitch the actual universe so that by somethings frame of reference, it's moving faster than light. Maybe light will just speed up and the current speed of light is really because of some random thing trucking along at that speed and maybe someday it changes?

Maybe because light is both a wave and a particle, it's just setting its own standard for the wave speed by the particle speed.

It's stupid to assume there's more weird shit we haven't noticed yet.

And that's not even getting into the grey areas around FTL where you get between two points faster than light could, but you didn't travel the same distance between points.

Like, once physics gets complicated, if you think you understand it, it just means you dont.

The smartest physicist currently alive almost constantly tells people about how much he doesn't know, and that guy has pretty much all of human knowledge regarding math (not just physics) in his head.

He freaking came up with the ideas for MC Escher's most famous drawing (the stairs and hand drawing hand) when he was a bored teenager.

If Roger Penrose says he doesn't understand it none of us do.

[–] [email protected] 2 points 4 days ago

The stuff in the video makes sense, but what I can never understand is how we choose reference. Like if the space ship is the reference, wouldn’t everything else be moving at the speed of light and therefore slow down instead? Is it safe to assume some universal fixed point that’s everything else is moving around?

[–] [email protected] 2 points 5 days ago (1 children)
[–] [email protected] 0 points 5 days ago (1 children)

The simplest way I can explain it is that everything is always moving at the exact same speed, divided up between the three spacial dimensions and the time dimension. Light does not move through the time dimension at all, and therefore is always moving at full speed through the three spacial dimensions: ie. speed of light.

[–] just_another_person 3 points 5 days ago (1 children)
[–] [email protected] -1 points 5 days ago (1 children)

I mean. You aren't wrong. Einstein went to his grave haunted by the notion that his explanation was missing something important, and nobody yet has been able to figure out what.

[–] just_another_person 0 points 5 days ago (1 children)

Photons don't interact with any of the three dimensions as we know them at all, especially time. They exist in all places AT the same time, theoretically, and they don't seem to dissipate based on the passage of time, but we literally have no way of proving that one way or another. They just seem to be around.

[–] [email protected] -1 points 5 days ago

Okay, I'll admit I was expecting you to have a better reasoning for what you said than "we don't know anything."

Also, the three spacial dimensions are the x, y and z axis. Time is the fourth dimension of Einstein's spacetime, which he did openly admit wasn't quite the right way of looking at it anyways, but rather it was just the best answer he could come up with.