# Driving at speed of light and then putting lights on.

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yes

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• 3 weeks later...

recently I've begun wondering why you get shorter as you speed up in special relativity

is it because time is slowing down?

anybody know the technical explanation of this?

I was also wondering what if there was a particle with mass (rest mass) but it lways traveled at c. would gravity just never advance infront of the particle?

if this is the case then gravity would look more like the wake of a boat correct? except with a wall (of gravity) infinitly close to the particle.

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Luke:

The phenomena u describes is called Lorentz contraction. And form an observer u will become thinner, altough u won't be able to measure it yourselve! And u will also only contract in the direction u are traveling.

A recent description i did read was that Gravity is a manifestation of time. when ut lift something out of a gravity field u lift it out of time. i bleive it was Penrose (not shure though) that mentioned this. Sorry for the bad description, but Penrose indeed mentioned this due to GR indicates this. Someone else might further emphasize this.

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recently I've begun wondering why you get shorter as you speed up in special relativity

is it because time is slowing down?

anybody know the technical explanation of this?

Length contaction and time dilation are direct consequences of c being finite.

As TheProphet said, it's Lorentz contraction, and you observe it of others that are moving relative to you. You never measure it happening to yourself.

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I'm only 14 years old but what I have read about quatum mechanics state that the observations made are relative to the speed and direction the observer is travelling.If you move at the speed of light(if it is possible),the observations you made constrast tradisional physics(where the observer is inert,or near inert).therefore,it is highly unlikely that you will see the light moving at the same speed as you.

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No, that's one of the strange things that confounds newcomers to relativity. The speed of light is the same for all inertial observers.

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my question was more why does the outside observer notice you contracting in a lorentz contraction

I understand that you can't measure it happening to yourself (inertial observer)

but why do you contract according to the outside observer

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my question was more why does the outside observer notice you contracting in a lorentz contraction

I understand that you can't measure it happening to yourself (inertial observer)

but why do you contract according to the outside observer

Because c is constant. It all follows from that, and the concept of simultanaeity.

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• 3 weeks later...

The speed of light is the same for all inertial observers(those who are at rest or constant motion).However,an accelerating observer will have different observations.Time is also warped for him.

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To a 19 yr old biology student in a physics class.

Relax!

I'm assuming you are in about a 2nd year of college, in a general physics class. Unless the Prof has stressed relativity in lectures, I would be very much surprised if this question was on a test for this class.

The thing to remember about relativity is that the speed of light, and all laws of physics, are the SAME for all frames of reference.

If you play ping pong in a fast space craft or a slowly moving earth, you play the same way

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To a 19 yr old biology student in a physics class.

Relax!

I'm assuming you are in about a 2nd year of college' date=' in a general physics class. Unless the Prof has stressed relativity in lectures, I would be very much surprised if this question was on a test for this class.

The thing to remember about relativity is that the speed of light, and all laws of physics, are the SAME for all frames of reference.

If you play ping pong in a fast space craft or a slowly moving earth, you play the same way[/quote']

That's probably not the best example, since playing ping-pong with and without gravity wouldn't be done the same way.

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• 2 weeks later...
is that like asking when traveling the speed of sound can you yell and hear yourself?

No, because sound requires a medium to travel in...

KAC

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Well not to small really but to thin in the travelin direction!

Probaply infinitly thin too! So there is yet another problem. Wounder how it will feel to be smashed into noithingess and back again!

But to the traveler, there is no "smashing" things traveling with them should appear to be the same.

KAC

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But to the traveler' date=' there is no "smashing" things traveling with them should appear to be the same.

KAC[/quote']

I was more of reffering to what happens with the traveler himself.

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I was more of reffering to what happens with the traveler himself.

From what POV? That was my point. To the traveler all should look and feel normal, right?

KAC

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