Thread: 186,000 miles a second?

Originally Posted by gococksDJS

Light itself is not relative in physics, it's the constant speed C . Light that is manipulated to travel slower than C, which is any light not traveling in a vacuum, is technically void of the laws of special relativity, because light traveling through our atmosphere is slower relative to light traveling through a vacuum.

But usually, observation is relative to your position in spacetime and that of the occurence being observed, except for light. Light is the only thing that will travel 3e8 m/s from any observation point. If you're on a train traveling (that is in a vacuum) at the speed of light and shine the beam, the speed of light would be the same for observers in the train as well as outside of the train, which is not true for the gun. It would be impossible to fire a bullet while traveling at the speed of light because that means that it would accelerate past the speed of light, which you can't do because it would violate causality. The bullet would have to accelerate from rest, while light does not accelerate relative to time, it has instantaneous acceleration.

I knew you couldn't resist a discussion with stephen hawkings aka nsimmons...

Originally Posted by BigDyl

I knew you couldn't resist a discussion with stephen hawkings aka nsimmons...

I'm Stephen Hawking, bitch.

Originally Posted by gococksDJS

holy balls, mudge is in the ninja club?

I just thought it was funny, I wanted to do another pic but I have to find it...

Your car would probably crumple into a dense blob of scrap well before the speed of light wouldn't it? So how would you manage to turn on the headlights?

Hey MYk that was a good idea. lol

Originally Posted by maniclion

Your car would probably crumple into a dense blob of scrap well before the speed of light wouldn't it? So how would you manage to turn on the headlights?

Well, this is the basis of particle accelerators. E=mc^2 shows that the closer to the speed of light you travel, the more energy you need, and since energy equals mass, your mass increases as well, so you would need infinite energy, which is impossible. The only theoretical possibility in a situation like this would be time dilation (which is what the twin paradox is), but this only matters if you arrive at a place who's reference of time is the same as where you left from, because if you were in the car, you would have no idea time was slowing for you unless you had a reference point that was stationary relative to yours in spacetime, and even then, you couldn't communicate in real time with the stationary observer because of the fact that from the travelers reference point, the earth is moving away from him, and from the earths reference point, the traveler is moving away, which is time dilation.

But if you are asking whether or not you would be able to physically move around to turn the lights on while traveling near the speed of light, you would be able to. You wouldn't know you were even traveling unless you had a stationary point of reference in spacetime, due to time dilation. It's like if two people float by each other in the vast emptiness of space, you have no idea which one is actually moving and which one is stationary.

True, i mean if you pass liek a planet perhaps, but then which one ismoving. Like on earth there is tree's and building, out there there is nothingness

Indeed!

Originally Posted by NEW_IN_THE_GAME

True, i mean if you pass liek a planet perhaps, but then which one ismoving. Like on earth there is tree's and building, out there there is nothingness

That's where cosmology requires a sense of imagination. If you choose the planet as the reference point, then the spaceship is moving, but if you chose the spaceship as your reference point, the earth is moving, and even if they both started with the same value of time, the value of time on one will never be equal to the value of time on the other, due to dilation. If you're traveling away from earth at 2e8 m/s, you can argue that earth is traveling away from you at 2e8 m/s. If the earth was moving, they would experience time dilation, but if you were moving, you would experience it, so who's actually being affected by it, or is it both?(But neither know they are being affected by it until they return and compare time values) This is also why it's impossible to pinpoint where the universe began, because if there was nothing, then you have no frame of reference. You can't say that the big bang occured 20 light years due east and 30 light years due south because you have no directional coordinates and no reference point in spacetime. To map movement in spacetime you use the four dimensions of spacetime and an endpoint, which is kind of hard to imagine because on earth we mostly only use two dimensional coordinates and an endpoint when giving directions. There's north/south, east/west and up/down, but you don't tell your friends to go 3 miles north, 2 miles south and 30 feet above sea level to get to your house, you only use two dimensions. If you remember that time is not a universal constant, and the effects of time dilation, it's easier to understand relativity.

This is an extremely interesting thread

Pick up The elegant universe by brian greene. Good book. Kaku's stuff is good to, but i find its repetitive.

Originally Posted by gococksDJS

That's where cosmology requires a sense of imagination. If you choose the planet as the reference point, then the spaceship is moving, but if you chose the spaceship as your reference point, the earth is moving, and even if they both started with the same value of time, the value of time on one will never be equal to the value of time on the other, due to dilation. If you're traveling away from earth at 2e8 m/s, you can argue that earth is traveling away from you at 2e8 m/s. If the earth was moving, they would experience time dilation, but if you were moving, you would experience it, so who's actually being affected by it, or is it both?(But neither know they are being affected by it until they return and compare time values) This is also why it's impossible to pinpoint where the universe began, because if there was nothing, then you have no frame of reference. You can't say that the big bang occured 20 light years due east and 30 light years due south because you have no directional coordinates and no reference point in spacetime. To map movement in spacetime you use the four dimensions of spacetime and an endpoint, which is kind of hard to imagine because on earth we mostly only use two dimensional coordinates and an endpoint when giving directions. There's north/south, east/west and up/down, but you don't tell your friends to go 3 miles north, 2 miles south and 30 feet above sea level to get to your house, you only use two dimensions. If you remember that time is not a universal constant, and the effects of time dilation, it's easier to understand relativity.

Time is what it takes for a Planet to orbit around its path.

Originally Posted by god hand

If you are in a car traveling at the speed of light and you turn the headlights on, what would happen?

The new BMW's have this covered...

Originally Posted by Lee Delroy

Time is what it takes for a Planet to orbit around its path.

Time can be whatever you make it. That's the whole point. Time isn't a universal constant. Also, the planets don't orbit around their own paths, they follow the path of least resistance of spacetime. According to relativity, an objects mass distorts spacetime and this geometric curvature is interpreted as gravity when it's actually a spacetime distortion. So the sun's mass causes a distortion of spacetime that the planets follow. Read "A Brief History of Time".

once again go cocks has this subject taken care of.