Comment on The speed of light
cannedtuna@lemmy.world 4 months ago
You have two observers, moving directly opposite each other.
Each has a flashlight pointing back at the other.
The speed of the light from those torched is the same for both observers.
(Instead the light would be red-shifted.)
Add a third observer, stationary to one and moving towards the other. As the third observer passes that observer, the speed of light from their flashlight never changes. (Instead it would go from being blue shifted to red shifted.)
This adds substantially more questions than it answers.
-Scientists after discovering General Relativity
It makes sense after accepting spacetime is mutable. Reference frames are merely referential localization.
It’s complicated (and don’t trust me too much, I’m not qualified), but if you’ve heard of time dilation and whatnot, if you start traveling at speeds comparable to the speed of light, spacetime distorts in such a way that from your point of view all light coming from any direction travels at the same speed.
This is also why (or one of the reasons) according to science you cannot travel faster than the speed of light, since light would still need to be traveling away from you at the speed of light and you’d need to occupy negative space in that direction, or something like that.
Different phases (colours of light) move at different speed, and have different longevity, I think. So how they always thought those pretty galaxy nebula photos, were red? Actually turns out that phase of light just travels for a longer time. Lasts longer. OK, now someone correct me, because I have absolutely no idea what I’m talking about. Just bring up vague floating memories from an article i read once.
The fact that this gif has a brief pause between the “ex” and the “explain” really irks me
It’s there to convey the line’s intonation.
Yeah, so it should be “Ex” and then add to it “plain” The way it currently is looks like a stutter, “ex-explain”
Well now it’s ruined for me
Ex…Term…Ah…Nate!!!
The simplest explanation I know: Nothing can travel faster than the speed of light. If you ever end up with something that makes the speed of light change, it’s actually time that changes.
whotookkarl@lemmy.dbzer0.com 4 months ago
When sailing boats pushed for speed they ended up hitting an unexpected speed barrier. As you increase velocity the break wave created by the bow of the ship elongates until the length of the ship is at 1 wavelength, then the hull drag prevents further acceleration. For a 50 meter ship it’s about 17 knots. You can get much faster lifting the boat from the water as you gain speed with an underwater wing, the current max speed was set 47 years ago at ~276 knots. But that’s only because they can remove the hull from the high drag environment and is extremely dangerous to attempt to break. The speed of light is nothing like that because spacetime itself can stretch and squish, I just wanted to talk about boats for a bit.
cannedtuna@lemmy.world 4 months ago
Still very interesting
icelimit@lemmy.ml 4 months ago
So you’re saying, we need to lift the spaceship out from space/time.
Sylvartas@lemmy.dbzer0.com 4 months ago
I’m not even mad because now I get why and how these competition multihull boats basically fly above water while keeping like 1% of the boat in water
anomnom@sh.itjust.works 4 months ago
Those ones are reaching a new speed limit as well, the cavitation around the hydrofoil starts at a certain speed/angle and stalls the foil, which then abruptly drops the hull back into the water.
I’ve been wondering how long before the equivalent of variable swept wings will be added to the cup boats.
kuberoot@discuss.tchncs.de 4 months ago
I love this because this feels like something the 10th doctor would say to confused daleks while stalling
NocturnalMorning@lemmy.world 4 months ago
I don’t like being deceived John! Tell me more about boats!