Wackedupwacko
Member
haha u wouldnt happen to goto nsb as well would u?
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Traveling at the speed of light! (2 Viewers)
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NightShadow
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haha noo noo i dont haha
AntiHyper
Revered Member
Well i think light doesn't always travel at a constant velocity. Think about transparent objects like water and diamond, where by Snell's law includes the change in light velocity.
So with that in mind.. we "can" travel faster than the light that travel in some object that can slow down its speed significantly.
Wackedupwacko
Member
o but we know that its just firstly when we talk about the speed of light its always through vacuums unless otherwise stated and 2ndly if im not wrong but 3x 10^8 m/s no matter how much u refract it (there is a limit dunno what tho) we still wont be able to travel at that speed with out technology 
The speed of light is not always constant (although the physics that is taught in high school makes you believe that it is). An electron in water can travel faster than light in water due to the refractive index of water. But this is beyond the scope of the syllabus.
For more information:
http://www.rpi.edu/dept/phys/Dept2/APPhys1/optics/optics/node4.html
For more information:
http://www.rpi.edu/dept/phys/Dept2/APPhys1/optics/optics/node4.html
Theoretically yes, practically no. If we were not moving at all, then time is moving at the speed of light thus it becomes imaginary this conferrs with the logic of Zeno's paradox and motion becomes paradoxical because it is moving in respect to something unexistant. Practically it is impossible because we are always moving.
Lions_Fist
Member
The real question with the time dilation and twin paradox question is when you change the frame of referance.
In your scenario, you put one twin in the space ship, one on Earth, and to the twin on earth, time in the space ship travels less slowly because of time dilation. When the twin returns, the twin in the space ship is younger, right?
What if we look at it the other way. To the twin in the space ship, the earth has traveled far away quickly, and time appears slower on earth than in the ship. When they return to earth, shouldn't the twin on earth be younger?
;P Hehe, enjoy working that one out.
In your scenario, you put one twin in the space ship, one on Earth, and to the twin on earth, time in the space ship travels less slowly because of time dilation. When the twin returns, the twin in the space ship is younger, right?
What if we look at it the other way. To the twin in the space ship, the earth has traveled far away quickly, and time appears slower on earth than in the ship. When they return to earth, shouldn't the twin on earth be younger?
;P Hehe, enjoy working that one out.
The twin's spaceship would have to be travelling at the speed of light, that isn't possible so you would be wrong. Also, the Earth's frame of reference would have to always be observing the spaceship for that to be possible. Furthermore, when the twin's spaceship is travelling at such a speed it is impossible to attain the speed at which your talking about because the being would be an atom and the twins would both age together due to quantum entanglement.
The interesting thing for me is that if you were the twin in the spaceship, from your frame of reference, as you travel through space, you would feel normal, ie you wouldn't know how much has gone by unless you looked back at the earth or something.
AntiHyper
Revered Member
I see your perspective, but maybe with a speed that is "approaching" the speed of light.Lions_Fist said:
The twins can see each other travelling at that speed, hence einsteins relativity equations would have the same effect on both of them.
That is to say, both twins would see each other's lengths contract, gained mass and time dilated; in effect cancelling out everything.
Pianpupodoel
Neurotic Member
That doesn't answer the question. Which twin is younger?AntiHyper said:
I
icycloud
Guest
You need General Relativity to show that the twin travelling on the space ship would be younger, because if a frame of reference is accelerating, the laws of Special Relativity don't hold true.
hydrobiont
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I agree with that.icycloud said:
The laws of special relativity only applies to inertial frame of reference.
The frame of the twin on the spaceship has not remained inertial, as the spaceship has accelerated, decelerated, turned around and then repeated it accelerations.
So, there is no paradox because the two frames of reference are not equivalent.
The textbook says the twin that has travelled on a spaceship will definitely be younger than the one remained on Earth.
AntiHyper
Revered Member
Hey you never think about the acceleration of earth around the sun! And the acceleration of our solar system around the galaxy! (maybe even the acceleration of the galaxy towards the edge of the universe)
Thinking about the bigger picture, you can't truly define THE frame of reference that will judge which twin will be younger. Purely because all objects available (such as Earth) is constantly changing velocity!
Well that's just my little exploration outside the textbook, i won't say more about it in this thread.. (going with the flow...)
Thinking about the bigger picture, you can't truly define THE frame of reference that will judge which twin will be younger. Purely because all objects available (such as Earth) is constantly changing velocity!
Well that's just my little exploration outside the textbook, i won't say more about it in this thread.. (going with the flow...)
insert-username
Wandering the Lacuna
Hey you never think about the acceleration of earth around the sun! And the acceleration of our solar system around the galaxy! (maybe even the acceleration of the galaxy towards the edge of the universe)
Whether or not the Earth/Solar System is actually accelerating as opposed to moving with a constant velocity with regard to the Galaxy is possibly a point of debate (the galaxy is most like accelerating out from the centre of the universe at least). Is the Earth actually accelerating with regard to the sun, and the solar system with regard to the galaxy?
I_F
Whether or not the Earth/Solar System is actually accelerating as opposed to moving with a constant velocity with regard to the Galaxy is possibly a point of debate (the galaxy is most like accelerating out from the centre of the universe at least). Is the Earth actually accelerating with regard to the sun, and the solar system with regard to the galaxy?
I_F