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Old Feb 17th 2015, 03:09 AM   #1
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Physics Of Optics And Time

PHYSICS OF OPTICS AND TIME
Any corrections, different point of view and criticism will be appreciated pls.
ABSTRACT: A brief proposition on the nature of light waves and how it affects the measurement of observers. For example, when a disturbance is created in the waves of light due to the motion of an object, this disturbance does not just die out of existence. It goes on to affect the observation and measurements of all observers who depend on the light waves for their observation and measurement. This change in the physical property of the light waves can make physical measurements of different frames to appear relative depending on the magnitude of the disturbance produced in the waves of light.
INTRODUCTION:
In this proposition on light waves and time, I wish to explain how the light waves surrounding a moving object affect the physical information about the motion of the object as measured by observers of different frames. According to Doppler's effect, during the motion of an object, the light waves reflected/emitted from the moving object either gets closer or further apart from each other and this results in changes, for example, the Blue or Red shift of a fast moving source of light. On the other hand, this change imposed on the physical properties of the surrounding light waves due to the motion of an object results in a phenomenon which I will summarize below.
"In a given system of an observable experiment, A change in the physical properties (E.g. Wavelength, Period etc) of the motion of the light waves emitted/reflected by an object due to motion, Results in change in the physical properties (E.g. Time, Distance etc) of the motion of the object as measured by observers of different frames."
Simply, change in the physical properties of the motion of the surrounding light waves, Results in the Relativistic Effects we observe in our measurements.
Every light source which emits light waves, has a series of light waves spreading out from its vicinity and likewise a body in an illuminated region of space, has a series of light waves spreading out from its vicinity. Light waves act as a medium by which some information about an object, either at rest or in motion, propagate from one region of space to another. Observation of most events is possible because of the ability of light waves to transmit information about an event to an observer located at a distance in space.
Imagine an isolated region of space with just one light source that emits uniform light waves strong enough to illuminate all regions of that space. let's have a stationary observer located somewhere on a plane surface in that region, and an object (car) of velocity V, located at a distance D, away from the stationary observer. Any observer located within this region of space who wishes to observe the motion of the car will depend on the light waves (either visible or non visible electromagnetic waves) emitted/reflected by the moving object for information about the motion of the object.
To the stationary observer who is at a distance of D, behind the car, let us analyze his observation and measurement of the time of motion of the car through a distance d. Let us take that the speed of light in this thought experiment is C.
Light waves propagates information about an event from one region of space to another and it takes some time for light to propagate information about an event. During the measurement of the time of motion of the car by the stationary observer, the surrounding light waves also takes some little time to propagate information about the motion of the car to the stationary observer. This propagation of information by light waves matters most at the point when the car is just about to start its motion and at the point when the car immediately comes to rest.
MATHEMATICAL DERIVATION;
Let us assume that the car has a clock attached to it which will record the time of its motion through the distance d and let us use the time, t, as the time measured by the clock attached to the car, for the motion of the car through the distance d.
Let us assume that the stationary observer is also provided with a clock that will enable him to time the motion of the car through the distance d, and let the time he measures for the motion of the car through the distance d, be T.
At the start of motion of the car, when the stationary observer starts his clock, the stationary observer DELAYS in starting his timing on the motion of the car by a time delay of amount equal to D/C, which is the time for light signal to travel from the car to the stationary observer and inform him of the departure of the car, which means that the stationary observer starts his timing at the time t - D/C. Also, at the end of motion of the car, through the distance of d, the stationary observer will require another light signal to travel from the final point of motion of the car to the point of the stationary observer to inform him about the coming to rest of the car. The time for this last light signal to get to the observer is d/C + D/C . This means that the stationary observer EXCEEDED in his measurement by the amount of time d/C + D/C . The total time resulting from the light propagation effect is D/C + d/C + D/C.
Therefore the total time T, of motion of the car as recorded by the clock of the stationary observer is T = t - D/C + d/C + D/C. The propagation time of information by light can be removed in the above equation of time as below, -D/C + (+D/C) = 0.
Simplifying the equation gives:
T = t + d/C
d/C = T - t ............................................ .............. 1
The factor d/C is not a light propagation time but a change in the physical property (Period/time) of the surrounding light waves. and I will prove further the origin of the factor d/C.
The above equation simply says that: "Change in the physical property of the motion of the surrounding light waves equals (=) Change in the measurements of observers of different frames, that's the Relativistic Effects we observe in our physical measurements"
Since d = vt, where v is the velocity of the car.
T = t + vt/C
Therefore;
T = t (1+v/C)............................................ ....................... 2
To prove further that the factor d/C is a change in the physical property of light waves, precisely, a change in the period of the light waves, let's consider the below analysis using the Doppler's Effect.
Now, imagine a car that emits light of wavelength ƛ , when it is at rest but when it is in motion, it emits light pulse of wavelength ʎ . Let's take that the car is to travel away at a speed of v on a straight line from a stationary observer located at a distance of D behind the car and this car emits a pulse of light at a period of t when in motion. If at the beginning of the motion when the car is just about to move, it emits a pulse of light and after a time, t, it emits another pulse of light and comes to rest immediately, then it will be clear that the car travels a distance, d, during the t period of emission of the pulse of light.
Mathematically, the period t, of emission of the light pulse is the same as the time (t) of motion of the car through the distance, d. The distance, d, travelled by the car during the period of emission of the light pulse is:
d = vt
Also, the change in the wavelength of the light waves brought about by the motion of the car is expressed as:
ƛ - ʎ = d = vt .................................................. ....................................... 3
From equation 3,
ƛ - ʎ = d = Vt
d = ƛ - ʎ
substituting d in equation 1 gives:
T - t = d/c
T - t = ƛ - ʎ /C
Therefore:
ƛ - ʎ /C = T - t = d/C .................................................. .....................4
The above equation shows that "In any given system of an observable experiment, change in the physical information about the motion of light waves, due to motion of an object, results in change in the physical measurement of the information about the motion of that object as measured by observers of different frames." That is to say; changes in the physical properties of light waves results to the Relativistic Effects we observe in our physical measurements.
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Old Feb 17th 2015, 03:10 AM   #2
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Optics And Time

THE CORRESPONDING DISTANCE EQUATION;
The corresponding distance can be derived through a more detailed form but let me use this short cut. From equation 1
T = t + d/C
since t = d/v
then:
T = do /v
Therefore: do /v = d/v + d/C
do = d (1+v/C) ........................................5
T and do is the respective time and distance travelled by the car, as measured by the stationary observer.
t and d is the respective time and distance travelled by the car as measured by the car or a clock attached to the car.
d/C is the change in the physical property of the light wave, which is also a change in the period of the light waves that were emitted when the car is at rest and when it is in motion..
This effect has been misinterpreted by other writers who claim that light travels a longer distance in a moving frame and thereby causing time to run differently in different frames. But it is very clear from the above derivation of time and distance that light travels through the same distance in all frames and time also runs the same in all frames. But what happens is that, when a disturbance is created in the waves of light due to the motion of an object, this disturbance does not just die out of existence. It goes on to affect the observation and measurements of all observers who depend on the light waves for their observation and measurement. This change in the physical property of the light waves can make physical measurements of different frames to appear relative depending on the magnitude of the disturbance produced in the waves of light..
The laws of physics are very absolute in the sense that in reality, light travels the same distance relative to every frame BUT the laws of physics could be relative in the sense that in measurement, observers of different frames might measure different values for the distance travelled by the light waves as a result of the behavior of light waves which I explained above.
Also, the measurements of some frames are better/more valid than the measurement of other frames, depending on the resultant change in the physical property of the light waves from both the system of the observer and the event being observed. It seems from the derived mathematical equations that the measurements recorded by a person attached to the frame of the event are always more accurate, and this must be because of the fact that the person attached to the frame of event does not depend on the surrounding light waves for its measurement. Of course, no one needs light waves to walk from point A to point B but someone surely needs light waves to know that an object has moved from point A to point B.
It does follow that (The motion of the Car results in changes in the physical properties of the waves (Doppler's Effect); The changes in the physical properties of the light waves results in changes/Relativistic Effects in the measurements of observers of different frames). In the earlier version of this proposition, this, I was referring to as "Nwobu's Effect" ( T - t = ƛ - ʎ /C = d/C ).
From the above derivations, the below conclusions can be deducted.
1. The velocity of any matter travelling through space is independent of any frame observing and measuring its motion.
2. Some matters can travel faster than the speed of light.
3. Some frames are better than others in the measurement of physical quantities.
4. Time runs the same in all frames even though our measuring devices may record otherwise.
5. Relative and absoluteness co-exist.
6. Between two or more inertial reference frames, an event which is present tense to one frame may not be present tense to other frames but may be past or future tense to other frames
7. Optical observation of our past time/world and its mathematical estimation is perfectly possible.
8. The future is not optically visible but is mathematically solvable.
For further reading on the complete article, search for the recent verison on Google. thanks
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Old Feb 17th 2015, 11:48 AM   #3
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While I see the general direction of your thought, and the individual steps are generally reasonable, you seem to be getting a bit tangled in some of your arguments, and therefore coming away with incorrect conclusions.

The starting point of the time taken for the propagation of information seems sensible.

You are correct that different observers determining the time it takes for a moving object to pass two points will give different answers due to the time it takes for the information to propagate to them.

Slowing down the propagation of information (to the speed of sound) might help clarify:
Imagine an observer at the side of a (straight) railway, as a train passes it whistles,
some time later it whistles again.
Put a second observer on the side of the track midway between these two whistling points.
The second observer will record a shorter time between hearing the two whistles than the first observer.

This is all fine, but I start to loose you when you start to bring the doppler effect in...
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Old Feb 17th 2015, 04:44 PM   #4
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Hello MBW, thanks for your comment and for taking time to go through the article. yes i agree with what you explained. But the reason why the proposition included Doppler's effect is because when an observable object moves during an experiment, it just affects the emitted light waves as a result of its motion. The mere motion of the object brings the Doppler's Effect into existence.

Also, I used the Doppler's Effect to Prove further the origin and meaning of the factor d/C which came out in the equation T - t = d/C . And from the equation, I was able to come to the conclusion that the change in the properties of the light waves, affects measurement of observers of different frames in a relativistic manner. The factor d/C is a change is the period of the light waves emitted at rest and while in Motion. while T - t is a change in time of motion of an object measured by a stationary observer and a clock attached to the moving object.

The Doppler's Effect as we know it, is simply the effect of a moving object on the emitted light waves. My proposition on the other hand is simply the effect of the disturbed light waves on the experimental measurements of different observers. Mathematically T - t = ƛ - ʎ /C = d/C .

Thank you. and let me know if you have any more questions.
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Old Feb 19th 2015, 11:44 AM   #5
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Sorry that I am picking away at this so slowly,
(I haven't got much spare capacity at the moment)

In your equation 3, your car is moving just exactly one wavelength.
Is that correct?

Again moving this into a "normal world scale" with the train and trying to paraphrase:
Let the train sound its whistle for exactly N cycles of the whistle frequency.
The train will then have moved N wavelengths between starting and stopping the whistle.
Position two observers at the side of the track, one behind the point at which the train starts whistling, one ahead of the point where it stops whistling.
The 2 observers will disagree about the time duration of the whistle blowing,
They will also disagree about the pitch of the whistle,
However they will both agree that the whistle was blowing for N cycles of the wavelength they heard.

I'm still not sure how this leads to your later conclusions.
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Old Feb 20th 2015, 06:48 AM   #6
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Hello MBW. thanks once again for the time and comment. The car actually did not move through a wavelength. it simply moved through the difference between the wavelengths. that is why the equation 3 has the form
ƛ - ʎ = d = vt ................ 3 . You might refer to the Doppler's theory for a better understanding of what i did on the equation 3.

Also, you wrote " I'm still not sure how this leads to your later conclusions.""
Do you mean the conclusion ƛ - ʎ = d = vt ....???

well, let me know if there is something that i am failing to explain. thanks
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Old Feb 22nd 2015, 05:06 PM   #7
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So basically what you are saying is
that if we determine the wavelength of the train whistle, with the train and observer both stationary,
then measure a distance along the train track equal to one wavelength of the whistle,
then have the moving train start and finish whistling at these two points.

the change in the observed wavelength (between an observer on the train and an observer at the side of the track) due to the Doppler shift will be equal to the difference in whistle duration observed by the observer on the train and the observer by the side of the track divided by the speed of sound.
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Old Feb 25th 2015, 05:56 PM   #8
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I realized you really interpreted the proposition well only after i had already written the below but i thought i would just post it still. you made a little mistake in your conclusion.

Hello, i don't think i understood your last paragraph very well, but let me explain it in the same terms like you used.

I was not able to figure our the exact locations you called "two points" in your sentence .......".....then have the moving train start and finish whistling at these two points."

what i am saying is this.

you have a train that blows whistle at a regular wavelength and frequency when it is at rest. while at rest, the wavelength of this whistles is fixed and the period of blowing of this whistle by the train is also fixed. and let us assume that this period is x seconds.

Now, imagine that this train decides to be in motion and blows the whistle. and also, let us take that the train travels under the time x seconds. in this case now, the x seconds will become period for blowing of 2 separate whistles, one at rest when it is just about to start motion and the other whistles when it just about to comes to rest.

and yes, you are right;

"The change in the observed wavelength (between an observer on the train and an observer at the side of the track divided by the speed of sound) due to the Doppler shift will be equal to the difference in the time { x seconds } of motion of the train observed by the observer on the train and the observer by the side of the track ."

I can't 100% say that the result of the equation would give the same result when we use sound waves but i must admit that i solved a similar problem using sound waves, and i got the same set of time equation. Maybe an actual experiment would help tell where everything rightfully fits.

Thanks very much for your broaden idea.
appreciated.

let me know if you have anything to say please.
Michael.

Last edited by Nwobuseffect; Feb 25th 2015 at 06:17 PM.
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Old Feb 27th 2015, 04:55 PM   #9
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I wanted to make sure that I had properly interpreted your original post before making this point.
There is a crucial difference between the interpretation using sound as the medium of information transfer and using light as the medium of information transfer.

If the observer on the train in on an open wagon, and measures the speed of sound in the direction of travel, and then again in the opposite direction, he will get different answers, because the the wind due to the motion of the train will change how fast the sound travels relative to the observer.
However the stationary observer (stationary with respect to the air) will measure the speed of sound as being the same in both directions.

However it has been experimentally confirmed, to an extreme level of accuracy, that no matter how fast the observer is moving, the speed of light observed remains the same whichever direction the light is going relative to the direction of travel.
Not only that, but the stationary observer will also observe exactly the same speed of light whichever direction it is going relative to the direction of travel.

This is very weird, totally ridiculous even, but it has been found, beyond any doubt, to be absolutely true!

This totally freaked out the physicists at the beginning of the 20th Century, but eventually Lorentz & Fitzgerald (amongst others) and of course Einstein showed that a self consistent reality could be constructed in which this weird effect would apply.
They then noted that if they followed this line of reasoning then it would result in many counter-intuitive consequences (some of which are very odd indeed).
Nearly all of these have now been confirmed by experiment (some would require unfeasibly large equipment to verify experimentally, which is why they haven't been).
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Old Feb 28th 2015, 04:30 PM   #10
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Hello, Thanks again. well i agree that the speed of sound and light are both constant and i also think that using sound as a medium of transmission of information, might produce some unexpected results, after all, the mathematics of the equations were created with light being the transmitter of information.

i agree that the speed of light is constant and I also got that through my equations. i also went on to derive that the speed of every other object is constant despite whatever any observer may perceive about the motion of the object.

It is unfortunate that my proposition did not agree with Einstein's relativity but i never expected it to agree with special relativity. It is an Idea with different basis and as such, its predictions are not exactly the same as Einstein's.

Anyway, thanks for the comments.
enjoy your day.
Michael.
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