# Travelling at the speed of light

#### Koveras00

What will the world appears to a observer travelling at the speed of light?

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#### STAii

An observer cannot move at the speed of light.
Let's suppose it is moving really near to the speed of light.
He will see everything shrinking in the direction of its movement by the factor of [squ](1-(v2/c2)) .

#### dg

Originally posted by Koveras00
What will the world appears to a observer travelling at the speed of light?
As STAii already explained, according to special relativity, the speed of light cannot be reached by any massive object. Still travelling at subluminal speed can offer very interesting effects since all the light seen by such a fast observer would be changing both in color and direction.
All the light coming from the rear of the observer would redshift, all the light coming from the front would blueshift.
But the most interesting effect would be that all rays of light would be seen in different directions: the light coming from any direction will start appearing just as if it was coming from a direction closer to the front of us (direction of velocity). At a high enough speed all the light would appear in front of us, until closing into a single point.

I remember a really nice book by some Kaufmann guy on this subject... not much more.

Ask more if I did not make myself clear (is pretty late here... and not only that, ;) ), Dario

#### Koveras00

Re: Re: Travelling at the speed of light

Originally posted by dg

But the most interesting effect would be that all rays of light would be seen in different directions: the light coming from any direction will start appearing just as if it was coming from a direction closer to the front of us (direction of velocity). At a high enough speed all the light would appear in front of us, until closing into a single point.

I remember a really nice book by some Kaufmann guy on this subject... not much more.

I do not understand this part. ANd may i ask how the sequence of events differ frm the moving observer and the stationary one?

And one more, what is the title of this book?

#### anil

remember

Maximum speed cannot be acheived through moment of an object body. Only waves can, because in a wave no atoms physically move but is caused by transferring an energy from atom-to-atom (rember the atoms vibrate). It's not impossib;e to make a rocket travel at a speed of light but will cause more complex problem. Many problems come ito action such as speed varying on air pressure. Till today's date wave is known as the most effeciant way to tranfer energy.

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#### RuroumiKenshin

wouldn't the world appear to be blueshifted?

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