young

It could work with the right circumstances, but not as advertised.

this is one is bad

the best is the rod extending from Earth to Mars, "problem Einstein?"

Yeah, since a lot people don't understand that pressure waves travel at the speed of sound so a lot of people actually think it could work, and they think the only reason it wouldn't be possible is because "well you can't build a rod that big".

So lets say it is possible and we do shoot a giant mirror into space 10 lightyears away and look directly at it with a telescope, What would you be seeing? I understand the concept that when we look at stars and galaxies billions of light years away we're looking at them in the past because the image takes so long to travel. But what would we see if we reflected an image back to us? would it be us standing there? Would it take too long to generate an image therefore not seeing anything?

The "right circumstances" would be standing at the telescope for twenty years, after which you would start to see yourself at the time you started standing there. That is, assuming you, the Earth, and the mirror were all stationary relative to each other the entire time

So what would you see instantly? whatever was there 20 years before that?

Yup.

So technically therefore if we were to ever construct such a mechanism and had the capability to make it work, then we could, in theory, be able to look into the past?

Highly intriguing.

As a side question that popped into my mind while pondering this. If you choose to look into the past with such a device, the outcome(or what you're looking at) has to have already been predetermined?

So lets say it's 20 years ago, in same exact spot where the telescope would view. That point in time there is no telescope, no person looking through it. Yet 20 years later you can see back to that time period?

I love time travel discussion.

This post was edited by TheInferno on Oct 30 2011 02:31pm

Yeah you could look back 20 years in time, but that's not time travel. It's really not that different from if you were to record something from a satellite in direct orbit from earth that sent back its information on a 20 year delay. Or really even more simply, it's the same concept as watching a home movie from twenty years ago. You can watch yourself as a kid, but you know exactly what's going to happen since it's already happened.