Relationship between speed and time

[arkain101]

There is no such thing as motion in ones observer frame. Motion only exists when there is another object to compare distances with. This is the reason why the observer frame always remains the same, because there is no velocity for it. The only thing it can claim is that another frame and its own frame are moving

If there was an absolute rest then it would be possible to say whether or not an object is moving. But according to modern theory, there is no absolute rest so, there is no absolute motion, by this I mean no one observer frame can say how fast it moves if it moves at all but can only compare the relavent distance/time in use of another object that has no specific velocity (according to its own observation posistion.

The claim one can make is that the fastest possible displacement change between two objects is C. The data of an objects position is determined by light that radiates from the object. And so, when two objects are closing in at velocity close to C, the light which supplys the information on the position of each object can determine whether or not an object is carrying more or less velocity than the other by the use of light, object true position, and time between those two peices of information. In Special relativity, time flexes to allow any velocity to exist, ones in which exceed C when two objects close in both carrying speeds close to C. The theory must apply the notion that the total velocity must be devided among the two objects correctly to force the assumed velocity below C for each object. This directly imposes the ground bases for a proposed absolute rest. As each observer will 'see' an object moving beyond C, the redshift in the light would be to one end of the scale, and time must be slown down so dramatically on the respected object of motion in order for its light to meet the destination before the physical object.

[Jay-qu]

Jay Qu, I did not mean to sound impudent in my last post, and I meant no disrespect to your offer of help. If you took it as such, I apologize, I was just struggling to understand something that isn't very easy to understand.

 

No need to apologise mate, as Qfwfq was getting at - its not an easy topic and I dont fully understand it (yet) so if your struggling no worries, many other people do aswell. :naughty:

[D3nt]

That's a very good point you made. I never threw the motion of our galaxy into my equation because in thinking of the human within the confines of the spaceship, I neglected that they would also be subject to the motions of the galaxy around it. Also, I'm glad you cleared up the fact that the brain's impulses do not travel at the speed of light; I had always assumed they did, and assumptions can be dangerous. We keep coming back to the relativity of time, and we are all, I believe, agreed that time would continue as normal to the person travelling close to c. Perhaps I should take another approach to my question, though I'm sure it will meet with the same results.

 

Time does not slow for the individual travelling at 292,000 km/s-- as all the posts have stated, time would pass for him without any change. To the observer on the ground, however, the traveller's time is passing much slower. Therefore, to begin my question, we begin with the observer, as opposed to the traveller. This way, we bypass the factor that time is relative; We are focusing on the observer whose time is t, and through this alone we are able to note that the traveller's time is indeed dilated. Now that this is established, I will move on.

 

I want to focus on the ideas presented in the link submitted by Kamil. The diagram is at the top of the page

http://www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm#simultaneity

 

 

To the non moving observer, the amount of ticks they record are fewer than those on board the shuttle. This is because light must travel a "horizontal" distance while waiting for its the light to bounce back on a "vertical" trajectory. This is why I feel justified in my first notion, and as you've already mentioned, QF, the impulses in the brain travel slower than light. If light slows because it must travel a relativistic "horizontal" distance in addition to its "vertical" distance, would the same not hold true, to the earth based observer, of the signals in the brain, despite the short distance they must travel. Because, to the stationary observer, the traveller (although he appears to the stationary observer to contract) is in a sense a being who in a given second occupies 292,000 km of space. Though the traveller does not experience this, as his time is unchanged in his own frame of reference, the observer (despite being unable to physically see it) is seeing the slower then light impulse travel 292,000 km + whatever distance/ sec. The same would seem to hold true for everything because all information, even that transmitted at c, would be travelling this added distance.

The posts have done an excellent job detailing that time is relative. But what are your ideas as to why this physically occurs, aside from the fact that time is relative? Is any part of my idea feasible? And if not, what do you believe is more feasible?

 

Dent

[arkain101]

It all comes down to the assumption (or fact?) that light will always travel the same velocity according to an observer. There is no velocity for an observer there is only comparisons between two or more frames.

So special relativity postulates that matter will detect light as the same velocity in its own reference frame no matter how fast another reference frame confirms it is moving. Next we look at the constant of light having a finite speed, no less, no more. So when you compare measurements of light speed for observer in motion (a) and observer at rest (:naughty: measuring the light on the moving observers frame (a), The math says, the only way to uphold lights constant value is for time to be relative each observer.

[arkain101]

I have been searching around for experiments that show how light is always the same velocity to the observer. Id like to see a couple to see exactly how they describe this as fact since there is so many ways to look at what constant means.

[arkain101]

Time Dilation for Particles

Particle processes have an intrinsic clock that determines the half-life of a decay process. However, the rate at which the clock ticks in a moving frame, as observed by a static observer, is slower than the rate of a static clock. Therefore, the half-life of a moving particles appears, to the static observer, to be increased by the factor gamma.

 

For example, let's look at a particle sometimes created at SLAC known as a tau. In the frame of reference where the tau particle is at rest, its lifetime is known to be approximately 3.05 x 10-13 s. To calculate how far it travels before decaying, we could try to use the familiar equation distance equals speed times time. It travels so close to the speed of light that we can use c = 3x108 m/sec for the speed of the particle. (As we will see below, the speed of light in a vacuum is the highest speed attainable.) If you do the calculation you find the distance traveled should be 9.15 x 10-5 meters.

 

d = v t

 

d = (3 x 108 m/sec)( 3.05 x 10-13 s) = 9.15 x 10-5 m

 

Here comes the weird part - we measure the tau particle to travel further than this!

 

Pause to think about that for a moment. This result is totally contradictory to everyday experience. If you are not puzzled by it, either you already know all about relativity or you have not been reading carefully.

 

What is the resolution of this apparent paradox? The answer lies in time dilation. In our laboratory, the tau particle is moving. The decay time of the tau can be seen as a moving clock. According to relativity, moving clocks tick more slowly than static clocks.

 

We use this fact to multiply the time of travel in the taus moving frame by gamma, this gives the time that we will measure. Then this time times c, the approximate speed of the tau, will give us the distance we expect a high energy tau to travel.

 

What is gamma in this case? It depends on the tau's energy. A typical SLAC tau particle has a gamma = 20. Therefore, we detect the tau to decay in an average distance of 20 x (9.15 x 10-5 m) = 1.8 x 10-3 m or approximately 1.8 millimeters. This is 20 times further than we expect it to go if we use classical rather than relativistic physics. (Of course, we actually observe a spread of decay times according to the exponential decay law and a corresponding spread of distances. In fact, we use the measured distribution of distances to find the tau half-life.)

 

Observations particles with a variety of velocities have shown that time dilation is a real effect. In fact the only reason cosmic ray muons ever reach the surface of the earth before decaying is the time dilation effect.

 

So the particle would presumeably move from point A to point B, when at point B it would send out a burst of energy clarifying its life has ended. So we could measure velocity and burst and assume it should travel, such and such mm. But as it says, the particle covered more distance that expected according to its life time.

Here is an explanation. (the light represents the particle in the accelerator)

 

We have a light that turns on for 1 second, 60 times each second (LED light) then off for 1 second. (it represents a particle in feasable scale to witness the frequency of the light waves).

 

We set up the light in the laboratory and mount it and point a device at it that measures how long it appears to be turned on. With this high sensitive device it detects 60 flashes in one second. With the human eye we see a short blip of light as if it only flashed once for one second.

 

We use some calculations and say, at 100,000 km/second the light will cover 100,000 kilometers between each point it flashes on.

 

Now when we go and hook this light up to a hypothetical rocket and it flies by us at 100,000km/sec.

 

there is 60 flashes of light each second. As the light passes by at this incredible speed, each one of the 60 flashes of light over a time of 1 second will be spaced by a distance of 1666kilometers. Then nothing for another 100,000km, then again 60 independent blips of light over a distance of 1666km between each milisecond blip.

 

In logical thinking we would expect the light to appear everry 100,000km for one second with our nake eye, and cover 100,000km each time it turns on.

 

What we would see is 60 lights spanned over 100,000km with a distance of 1666km between each light in that one second it apears.

 

So in the particle accelerator, we would expect the particle to flash at point B, and show that it traveled thus far. But according to their results it showed the particle traveling a futher distance than expected, but when adding in the factor of some hundreds of thousands of blips of light spanned over distance of particle flash time x particle speed, it would appear that in fact the particle blipped over an incredible distance replicating its position hundreds of thousands of times, over a period of time at the velocity C.

 

And only when the detector is not tracking the particle does it create a multiple representation of itself.

 

If we go back to our light example and follow the light with our eye (assume we can see it when it is not on) we would see it like it looked on the table in the lab appearing for 1 second. But when we stare in the path and do not follow the light we would get the 60 spaced lights.

 

I wonder if this possibility could be responsible for a particle appearing to live over a longer distance.. Its a bit difficult to decide with thought expiriments.. one would have to check with some pretty heavy mathamatics to get a conclusion.

[Matat]

What is the speed of univers? This will answer some questions :lol:

[madmadmax]

What is the speed of univers? This will answer some questions :lol:

 

Universe is everything and anything proven to exist. Finding the speed of universe is impossible.

 

EDIT: Sorry necro-post by mistake lol