Why do we judge time by light?

[russ_watters]

As an engineer, I don't see it that way at all (and I doubt scientists and artists do either). Devices such as cameras and staplers are objects and they are products of the minds of their inventors. Despite what Michelangelo said, the statue of David was not there before he removed the excess marble. The laws of physics are there already and are simply waiting to be discovered.

Something that is invented does not exist (is not real) before you invent it - something that you discover is real before you discover it. Ie, mount Everest was most certainly there before anyone knew it was there.

I think you are using the words "discover", "invent", and "real" incorrectly.

 

[dgoodpasture2005]

As an engineer, I don't see it that way at all (and I doubt scientists and artists do either). Devices such as cameras and staplers are objects and they are products of the minds of their inventors. Despite what Michelangelo said, the statue of David was not there before he removed the excess marble. The laws of physics are there already and are simply waiting to be discovered.
Something that is invented does not exist (is not real) before you invent it - something that you discover is real before you discover it. Ie, mount Everest was most certainly there before anyone knew it was there.
I think you are using the words "discover", "invent", and "real" incorrectly.

But they do already exist... they are all bi-products of discovering of the mechanics that make them work... which already exist(inside the laws of this universe)... and are only waiting to be discovered. I am a scientist and a philosopher. Everytime an invention is made, it's just the discovering of laws that allow them to be created and carry out the functions they are able to carry out. I understand what you're saying, don't get me wrong, i am just looking at things a bit larger.(i agree to disagree, as i think both of our points are right, on different levels) Discover and invent are synonyms. So are real and exist. I re-defined what i meant by real. I don't know what you meant by artists.. so please don't be offended if i took you wrong, but artists don't necessarily invent or discover anything, they create paintings from previous discoveries such as paint and paper... and use their imaginations to project the image. Although this is getting interesting on how different professions might view the concept of discover/invent/create.

 

[dgoodpasture2005]

I want to be a little bit hypothetical just so we can think a little bit differently about the definitions... one might call them "inventions" today... but say we're around for another 2 million years... and inventions are pretty much... done with... would they switch to being called discoveries?

 

[dgoodpasture2005]

I think of it like this... every answer one could possibly desire... lay dorment in their brain. If you want the answers, you need to get the information. When you get the information, the answers become clearer.

 

[Janus]

We already have a notion of time, but when Einstien uses a light clock in his thought expirements instead of a pendulium (or other matter based clock) is it possible that the (at that time presumed unique) charastics of light could in some way alter how time was view.
As has been mentioned before if Einstein had used a bouncing ball instead of light relativity would be much differnt today.

To answer your question we can consider the situation where you use both the the light clock and the bouncing ball.

Start in the frame where the light clock is at rest. The ball bounces straight up and down, and in the time it takes the ball to make the round trip the light clock ticks x times. Assume that there is a device that records both the ball bounces and ticks of the light clock, say a piece of tape that both the ball and light leave a mark on they bounce back and forth. The piece of tape moves relative to the light clock such that you get a mark from the ball followed by a series of marks made by the light followed by another mark made by the ball.

Something like this:
o...o...o...o...o

Know consider how things appear from the a frame in which this whole apparatus is moving. The light and ball still bounce back and forth and still make marks on the tape. However, the light and ball follow a zig zag path as seen from this frame. Now the light must travel at c, so in traveling a longer zig zag path rather than a shorter straight up and down it will take a longer time between each mark made on the tape as seen from this frame. (we see time dilation)

Now, if as you suggest, the Bouncing ball would give a new type of relativity, then its time between marks would be would not change at all, or change by a different factor. But then this observer would see the marks made on the tape look maybe like this:

0...0...0...0

With fewer light marks between each ball mark.
But how can two observers see a different number of marks on the same piece of tape? Especially when at the end of this experiment both observers and the tape could be put in the same room.

The answer is that they can't, and therefore the bouncing ball must undergo the same time dilation as the light clock does, so that at the end, both observers agree as to how many light marks are between each ball mark.

Thus using a bouncing ball instead of a light pulse will give you the same relativity.

 

[Wizardsblade]

Janus

Very good illustration of relativity. Einstein’s theory has very good merits, but I hope to some day find a more homogenous space/time theory. If one was every made that met experimental data as well as Einstein's theory would you be willing to entertain it?