okay not homework question or anything but would be nice to read what you guys think... If an alien man comes from a planet 3 light years away and travels at the speed of light to earth, and when he gets here he looks through a big telescope would he see himself leaving him home planet?

Question

anonymous · Answer

i think i can be the case the alien would have travelled in time enough to see himself leaving his planet coz when u travel wid such a great speed time limits itself and flows relatively slower..........
flow of time is effected by t reasons 1 st can be the velocity wid which u travel + the mass of the body around which u travel....for example i f you move around a balck hole which is very dens and heavy time will again flow relatively slower......

anonymous · Answer

that is a very interesting idea i personally think that the alien would not be able to see him self because the photons which would have made him visible also left traveling at at the speed if light. maybe if somehow the alien were to go faster the then speed of light than the would have traveled faster than his photon could have. but that is what i think as a physics 1 student

anonymous · Answer

one more Einsteins conclusion was that you can travel slower than light or faster than light but you can never travel with the speed of light...

anonymous · Answer

No, it was that particles with mass may only travel with a speed less than the speed of light.

shayaan_mustafa · Answer

Do you know our galaxy is 2500000 light years big. And science has proved atleast in our galaxy there is no such thing like human beings or alien. So how did you say about 3 light years away??

Regards,
Great fan of field Cosmology.

jamesj · Answer

"science has proved atleast in our galaxy there is no such thing like human beings or alien".  

What?  

Science has absolutely not shown any such thing.  If anything, every day we discover more planets around other stars, our level of confidence about the probability of other life in the universe increases.

shayaan_mustafa · Answer

@JamesJ.

Are you watching national geographic documentary of this January?
If no. Then see it first then we will discuss on this topic further.

Good Luck.