How Does Relativity Affect Our Perception of Time and Space?

[stonehaven]

Hi

I just had a thought this morning on the way into work, I’ve never heard a discussion on this before but I am sure there have been among someone. I will recap some obvious stuff first but keep in mind I’m just a regular dude who takes an interest in this stuff and likes to theorize and listen to others to learn and understand.

We use light for vision, light moves at 186k mi/sec, it takes time for light to get anywhere. in a vacuum light does not slow but in a gas light will slow?

In our everyday lives viewing the world around us we are viewing it about 50ns in the past, we don’t see any dramatic relative effects of time caused by speed or how fast things are moving around us because of the very nature they we perceive time, space, and matter together.

We can view stars and other galaxies from billions of light years away and see how they were billions of years ago because the time it takes light to get to us.

My thought i had was that if we could make something to accelerate us to near light speed while viewing a solar system billions of light years away. While viewing that solar system from our point of view that solar system will have to seem to be in fast-forward! That solar systems planets mooving around fast and so on, Likewise if someone was on Earth and was able to have a close view on us as we accelerated away they would see us go in slow-motion.



This of course would just be relative time to the observer, but real time (as we know it) is not changing right? According to theory of relativity time will change depending on how close you are to a dense gravitational field but aside from this?

How do we know time actually changes near a gravitational field?

I was looking at the formula of relativity E=mc^2 trying to figure out how Einstein came up with this, this looks like a simple equation you can even use ohms law to see how it breaks down a bit:
E=mc^2
c^2=E/m
m=E/c^2

but I just now realized I forgot that speed has 2 parts, time and distance, (or would it?) if so then:

E=m(d/t)^2
E=m(300km/1sec)^2

I am probably thinking of this to simplistically, for example m is probably gravitational mass and time may not even have 2 parts, it may just be a constant or something but I still can’t make out how time can bend or change. I’ll stop here since i have work to do but i think there’s enough here for others to discuss, comment, or criticize

thanks.
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[Janus]

Hi

I just had a thought this morning on the way into work, I’ve never heard a discussion on this before but I am sure there have been among someone. I will recap some obvious stuff first but keep in mind I’m just a regular dude who takes an interest in this stuff and likes to theorize and listen to others to learn and understand.

We use light for vision, light moves at 186k mi/sec, it takes time for light to get anywhere. in a vacuum light does not slow but in a gas light will slow?

In our everyday lives viewing the world around us we are viewing it about 50ns in the past, we don’t see any dramatic relative effects of time caused by speed or how fast things are moving around us because of the very nature they we perceive time, space, and matter together.

We can view stars and other galaxies from billions of light years away and see how they were billions of years ago because the time it takes light to get to us.

My thought i had was that if we could make something to accelerate us to near light speed while viewing a solar system billions of light years away. While viewing that solar system from our point of view that solar system will have to seem to be in fast-forward! That solar systems planets mooving around fast and so on, Likewise if someone was on Earth and was able to have a close view on us as we accelerated away they would see us go in slow-motion.

Yes, this is known as Doppler shift. It happens for pretty much the same reason that a Train whistle has a higher pitch when the train is approaching you than it has when it is receding.

This of course would just be relative time to the observer, but real time (as we know it) is not changing right? According to theory of relativity time will change depending on how close you are to a dense gravitational field but aside from this?

Relative motion has an effect on how we measure time also. A clock moving relative to you will tick slower than your own (regardless of what direction the clock is moving relative to you.) For instance, if a clock went away from you at some speed close to that of light and then returned, you will find that less time will have passed on that clock when it has returned. This is called "time dilation" and is unconnected to the Doppler shift. (though it will effect what you see in terms of Doppler effect. What you will see is "Relativistic Doppler shift" which is the Doppler effect with Relativity taken into account

How do we know time actually changes near a gravitational field?

By careful experiment:
http://en.wikipedia.org/wiki/Pound–Rebka_experiment

I was looking at the formula of relativity E=mc^2 trying to figure out how Einstein came up with this, this looks like a simple equation you can even use ohms law to see how it breaks down a bit:
E=mc^2
c^2=E/m
m=E/c^2

but I just now realized I forgot that speed has 2 parts, time and distance, (or would it?) if so then:

E=m(d/t)^2
E=m(300km/1sec)^2

I am probably thinking of this to simplistically, for example m is probably gravitational mass and time may not even have 2 parts, it may just be a constant or something but I still can’t make out how time can bend or change. I’ll stop here since i have work to do but i think there’s enough here for others to discuss, comment, or criticize

thanks.
-----------

E=mc^2 was derived from the consequences of the postulates of Relativity:

http://www.adamauton.com/warp/emc2.html