# jamesfairclear

Members

27

0 Neutral

• Rank
Quark

## Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

1. ## Is the Speed of Light variable?

This is my first post and as you can see it does not contain the expression "So either light propagates at c or it doesn't" Is red shifted light travelling at a speed less than c? Light emitted from a light source moving away from an observer at a speed v would intuitively be expected to be travelling at a speed c β v but is in fact still measured to be moving at a speed of c. The measurement of speed is based on the time interval between the light being emitted and the light being detected at the destination. The difference between light detected from a stationary source and light detected from a receding source is that the latter is red shifted which means that its wavelength has increased and consequently that it is less energetic. But what does that really mean? One can visualise it as follows: A Quanta of light (Photon) is released from moving light source. The next quanta (Photon) is released at a distance d from the first. Thus a relatively stationary observer will observe a greater distance between each quanta than an observer in the same inertial frame of reference as the moving light source; this is manifested as an increase in wavelength or decrease in frequency. If the wave from a stationary light source has a length L then the wave from a moving light source has a length L + n. If we consider that the full energy of the photon only arrives at the crest of the wave then the amount of energy arriving per second from the moving light source is less than that from the stationary light source. It takes longer for a FULL quanta of light to reach a point A where the light source is moving in a direction away from A than light from a relatively stationary source. Although energy from each quanta of light will arrive in a continuous stream as its waveform unfolds it cannot accurately be said to have arrived until the whole packet of energy has been absorbed at the destination point. As an analogy a locomotive leaves station A and collects one mile of carriages in front of it on its way to station B. The first carriage being pushed by the locomotive may arrive at a station B at 09:00 but the locomotive doesnβt arrive until 09:03. The speed of each quanta should be more accurately calculated as distance/time where time is the interval between the FULL quanta being discharged at source and the FULL quanta being fully absorbed at the destination. As its wavelength increases there can be a considerable interval between the arrival of the front of the wave and the back of the wave. In conclusion red shifted light from a receding light source can be measured in terms of the quantity of energy transmitted and received per second as travelling at a speed less than c. There seems to be some cross wires here. Please can you state in your own words your understanding of my proposition.
2. ## Is the Speed of Light variable?

My expression implicitly factors in the 2 frames of reference. With a receding light source and measuring a given quantity of light energy E emitted over a time T the distance D implicitly represents a known range of distances D1 to D2 that can be factored into the calculation with the same values at both source and destination thus effectively cancelling out to a simpler expression D.
3. ## Is the Speed of Light variable?

Measured speed of light over distance D for time T1 = D/T1 = c (Based on the usual definition of speed d/t) Adjusted speed of light = D/(T1+t) < c (This is the proposed adjustment to the value obtained by d/t) You state "You need to tell the new definition of speed before incorporating it into an explanation of speed of light. " . I have been stating and re-stating this until I am blue in the face π¨ My proposition is an alternative approach to measuring light speed more accurately by making adjustments to the value obtained from d/t in order to account for discrepancies in rates of energy transfer between source and destination in the special case where there is relative motion between source and destination. You take the standard (first past the post) definition of speed and then make an adjustment to account for the discrepancy between the rate of energy emitted and the rate of energy received. You state "Your math is not just incompatible with physics of light and speed of light". This is a very generalised statement. Please can you be more specific. You state "Because your very first post concluded with: So either light propagates at c or it doesn't." NO IT DIDN'T
4. ## Is the Speed of Light variable?

You state "All completely incorrect" without providing any explanation. It is abundantly clear from my proposition that I assume light (of any frequency) to be propagating at c. How have you interpreted this to be otherwise?
5. ## Is the Speed of Light variable?

No there is no conceptual error. With a receding light source and measuring a given quantity of light energy E emitted over a time T the distance D implicitly represents a known range of distances D1 to D2 that can be factored into the calculation with the same values at both source and destination thus effectively cancelling out to the simpler expression D. On the basis that D1 to D2 are known fixed values and that the light energy once emitted is no longer affected by the receding emitter it is known that the emitted light energy E will travel at a speed of c to the destination and will arrive there in a less energetic form due to the Doppler effect. The quantity of light energy emitted E over time T will take a longer time (T + t) to be received at the destination. Thus the only relevant parameter to the adjusted speed calculation is the additional time t taken for the energy discrepancy e to be received at the destination.

7. ## Is the Speed of Light variable?

Quantitatively there is less energy per second arriving at the destination from a receding light source than light from a relatively stationary light source. Energy emitted per second = E Energy received per second = (E β e) Energy discrepancy e received in t seconds. Energy emitted in T seconds = ET Energy received in T seconds = (E β e) x (T) Energy received in (T + t) seconds = ET Measured speed of light over distance D for time T1 = D/T1 = c Adjusted speed of light = D/(T1+t) < c

π
9. ## Is the Speed of Light variable?

Stranger things have happened π Yes indeed the apples and oranges do move at the same speed. I have never disputed this and have addressed this in more than one post e.g. "Light emitted from a light source moving away from an observer at a speed v would intuitively be expected to be travelling at a speed (c β v) but is in fact still measured to be moving at a speed of c. The measurement of speed is based on the time interval between the light being emitted and the light being initially detected at the destination." It is the fact that apples and oranges are not the same things that is relevant to my proposition to make a small change to the definition of speed.
10. ## Is the Speed of Light variable?

Yes I agree, I am indeed proposing a small change to the definition of speed. I am not though aware of any legislation preventing me from making such a proposal π I also agree with your statement "The source is further away when it emits the second photon. It has to travel a greater distance. That in no way means itβs traveling at a lower speed". I am proposing that the standard measurement of speed resulting in c is not an objectively accurate representation of speed where there is relative motion between the emitter and the destination because the light received (red shifted or blue shifted) is qualitatively and quantitatively different from the light that was emitted. One thing is emitted and another different thing arrives at the destination. In other words apples are being compared with oranges. As an analogy consider a 100 metre race where a competitor leaves the start line with an average chest to back measurement of 40cm which then increases to 40 metres by the time the front of his chest trips the photoelectric cell at a measured time of 11 elapsed seconds. If his back crosses the line 5 seconds later than his chest it raises considerable doubt as to whether he has run the race in 11 seconds or 16 seconds or some averaged time (say 13.5 seconds) between the 2 or indeed if he is really the same competitor that started the race.
11. ## Is the Speed of Light variable?

I am proposing that the standard measurement of speed resulting in c is not an objectively accurate representation of speed where there is relative motion between the emitter and the destination because the light received (red shifted or blue shifted) is qualitatively and quantitatively different from the light that was emitted. One thing is emitted and another different thing arrives at the destination. In other words apples are being compared with oranges. This is the best analogy I can come up with at the moment to illustrate why it is in my view more meaningful to make corrections to the measured speed of light in order to account for the discrepancies in light energy transfer rates between source and destination. Consider a 100 metre race where a competitor leaves the start line with an average chest to back measurement of 40cm which then increases to 40 metres by the time the front of his chest trips the photoelectric cell at a measured time of 11 elapsed seconds. If his back crosses the line 5 seconds later than his chest it raises considerable doubt as to whether he has run the race in 11 seconds or 16 seconds or some averaged time (say 13.5 seconds) between the 2 or indeed if he is really the same competitor that started the race.
12. ## Is the Speed of Light variable?

Interestingly if we look at your statement as to what you think is not a measurement of the speed of light "But that isn't a measurement of the speed of light. It is a measurement of ... well, energy transfer rate" and then write down what we think is a measurement of the speed of light we can arrive at one and the same definition. "We arrive at the the speed of light by measuring how long it takes a beam of light to travel a distance d in time t. A beam of light is a transfer of light energy from one location to another. Therefore the speed of light can be equally (and arguably more meaningfully) characterised as the rate at which light energy is transferred from one location to another." My proposal is an ALTERNATIVE method for measuring the speed of light in the special case where there is relative motion between the source and destination. If you read my proposal carefully you will see that it is not a measurement of energy transfer rate. It is an adjustment to the measured speed of light (which is nominally c using the standard approach) to take into account the discrepancy in energy transfer rates between source and destination. I repeat my analogy for further clarification: Imagine a 100 metre race where a competitor leaves the start line with an average chest to back measurement of 40cm which then increases to 40 metres by the time the front of his chest trips the photoelectric cell at a measured time of 11 elapsed seconds. If his back crosses the line 5 seconds later than his chest it raises considerable doubt as to whether he has run the race in 11 seconds or 16 seconds or some averaged time (say 13.5 seconds) between the 2 or indeed if he is really the same competitor that started the race.
13. ## Is the Speed of Light variable?

If you read the full details of my proposition which is an alternative approach to measuring the speed of light in terms of Energy transfer rates you will see that there are no such violations. Light received from a relatively stationary emitter A is more energetic than light received at a receding destination from the same emitter A. It follows that it will take longer for a given quantity of light energy (E) emitted by A to arrive at the receding destination than it does for the same given quantity of light energy (E) to arrive at the relatively stationary destination. The measured time from the start of light emission (throwing the switch) to the first moment when light is detected (arrival of the first photon) at either destination results in a calculated speed of c regardless of there being any relative motion between the source and destination. This standard method of measuring the speed of light does not take account of any discrepancies between the rates of transfer of Energy at the source and destination respectively. I am proposing that the standard measurement of speed resulting in c is not an objectively accurate representation of speed where there is relative motion between the emitter and the destination because the light received (red shifted or blue shifted) is qualitatively and quantitatively different from the light that was emitted. One thing is emitted and another different thing arrives at the destination. In other words apples are being compared with oranges. Imagine a 100 metre race where a competitor leaves the start line with an average chest to back measurement of 40cm which then increases to 40 metres by the time the front of his chest trips the photoelectric cell at a measured time of 11 elapsed seconds. If his back crosses the line 5 seconds later than his chest it raises considerable doubt as to whether he has run the race in 11 seconds or 16 seconds or indeed if he is really the same competitor that started the race.
14. ## Is the Speed of Light variable?

As far as I can see I did respond to your post on the topic of the relativistic Transverse Doppler shift but perhaps you anticipated a more detailed response? Current theory explains Red shift through classical Doppler shift and relativistic Transverse Doppler shift. In the latter case the calculations take account of time dilation in one of the 2 inertial frames of reference. For the purposes of relativistic calculations the speed of light is considered to be constant in all inertial frames of reference. From this it would be expected to follow that the rate of energy transfer from any light source (receding or not) will also be a constant as measured within a given inertial frame of reference. My proposition is based on the observational evidence that Red shifted light from a receding light source is less energetic at the destination than when emitted at the source. Whatever the cause/s of this though the widely accepted and well evidenced scientific fact remains that the light received is less energetic. I am more than happy to hear your Relativistic viewpoints on this topic.
15. ## Is the Speed of Light variable?

I don't think you have understood my proposition. Figuratively speaking yes.
×