spacetime

[granpa]

actually I've been thinking about that and I'm not sure. if objects can shrink in a gravitational field then maybe light waves do too.

 

science forums doesnt seem to be sending me the instant email notifications that it is supposed to. I only saw your post by chance.

[gre]

Why can't spacetime just be considered the velocity of a frame of reference (since a frame's time is dependent on its velocity)

 

Looking at: E = mc^2

 

energy = mass * (meters^2 / seconds^2) or mass * (velocity^2)

 

mass = energy * (seconds^2 / meters^2) or energy * (velocity^2) (inverse of velocity, but the meaning is the same)

 

This also explains why mass and energy are equals.

Edited December 24, 2008 by gre

[swansont]

Why can't spacetime just be considered the velocity of a frame of reference (since a frame's time is dependent on its velocity)

 

Looking at: E = mc^2

 

energy = mass * (meters^2 / seconds^2) or mass * (velocity^2)

 

mass = energy * (seconds^2 / meters^2) or energy * (velocity^2) (inverse of velocity, but the meaning is the same)

 

This also explains why mass and energy are equals.

 

I don't see the connections you're trying to make.

[gre]

I'm trying to show that meters (the only evidence of space) over seconds (the only evidence of time), can be equal to one, and together they're just a velocity.

[north]

Originally Posted by north

light is curved or bends because of the energy and/or matter in that region of space

 

Dude, light is curved because it is going through curved space, which is a manifestation of gravity.

"Gravity manifests itself as the curving of spacetime." -swansont

 

Is that relevant in determining whether you post was true or not?

 

the difference between you and I is this ;

 

for me energy and/or matter bends because of the energy/matter in that space

 

for example the suns atmosphere

 

for you however ;

 

light is curved by gravity and as you say manifests by curving space-time

 

but since neither space nor time has any substance associated with it , light cannot be bent because of space-time

 

that is the difference between me and you

[granpa]

actually I've been thinking about that and I'm not sure. if objects can shrink in a gravitational field then maybe light waves do too.

 

science forums doesnt seem to be sending me the instant email notifications that it is supposed to. I only saw your post by chance.

actually, after thinking more about it, here is how I see it. if it is space that stretches then yes light, of course, will seem to be compressed along with everything else. but if it is objects that become compressed, and space itself is unaffected, then I see no reason to think that light would be affected. light would only be affected by time dilation.

 

I could be wrong but thats my intuition.

[npts2020]

actually, after thinking more about it, here is how I see it. if it is space that stretches then yes light, of course, will seem to be compressed along with everything else. but if it is objects that become compressed, and space itself is unaffected, then I see no reason to think that light would be affected. light would only be affected by time dilation.

 

I could be wrong but thats my intuition.

 

Why then do we not notice the distance between the earth and moon or any other celestial object increasing as they become smaller?

[granpa]

Why then do we not notice the distance between the earth and moon or any other celestial object increasing as they become smaller?

you mean as the earths orbit takes it closer or further away from the sun, the earth and moon (and our meter sticks) should shrink and we should notice a change in the distance (as measured by our shrunken meter stick) between them?

[npts2020]

Well if the Earth and/or moon were getting smaller or larger but staying in the same orbits (relative to the center of the earth and center of the moon), the distance from surface to surface would change.