## Relative aging, an alternate relativistic method

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### Relative aging, an alternate relativistic method

This new method uses relativistic math and is fully compatible with relativity. It does not negate or disparage concepts such as length contraction, reciprocal time dilation, alternate perspective, sync offset, relativity of simultaneity, linear present time slices, Lorentz transforms, sync'd clock methodology, an x' axis, acceleration or clock handoffs, distributed sync'd clock networks (as multiple observers), or any type of spacetime interval equation, it just doesn't require any of these concepts to determine relative aging. All this new method requires is the formulas for the doppler shift ratio, c2=v2+ (c/Y)2, Y=c/sqrt(c2-v2)and t=Yt'.
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### Re: Relative aging, a alternate relativistic method

ralfcis » 13 Mar 2017, 03:00 wrote: All this new method requires is the formulas for the doppler shift ratio, c2=v2+ (c/Y)2, Y=c/sqrt(c2-v2)and t=Yt'.

OK, but I do not see the Doppler shift ratio appearing in your equations, which is just a reshuffle of the definition for gamma.

You must also be clear as whether you mean Doppler ratio (a synonym for Doppler factor), which is given by $f_s/f_o = \gamma\sqrt{1+v/c}$, where v is a relative velocity, $f_s$ means source and $f_o$ observed frequencies respectively.
Or whether you mean ratios of Doppler shifts, with the Doppler shift given by $z =f_s/f_o - 1$.

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### Re: Relative aging, a alternate relativistic method

The doppler shift ratio is ttx/t'rx = sqrt((c+v)/(c-v))

Graphically this relates the time t when the stationary frame transmits its spacetime info and the time t' when the moving frame receives it, each in their own proper time. (Relative aging is always a comparison of the frames' proper times as kept by on-board atomic clocks which are sync'd at the start of a journey and whose accuracy precludes the need for any sync'd distributed clock network.) v is negative if the frames are separating and positive if they're coming together.

The two participants are transmitting a TV image of their clock readout. That image is received by the other and compared with the rate their own clocks are advancing to ascertain what their relative spatial and temporal components of velocity are. v is the spatial component and c/Y is the temporal related by the equation:

c2=v2+(c/Y)2.

Since the formula for gamma can be written as Y=c/sqrt((c-v)(c+v)), the doppler shift ratio can be written as:

ttx/t'rx = Y(c+v)/c when considering the TV image speed the moving perspective sees of the stationary frame and

trx/t'tx = Y(c-v)/c when considering the TV image speed the stationary perspective sees of the moving frame.

Along with clock image info, the two participants return their position in space relative to a network of ly markers dispersed throughout the universe that are stationary wrt distances established by supernova markers relative to the earth. For shorter journeys within the solar system, the distances are calculated by planetary triangulation from the start of a journey when both participants are in the stationary reference frame (the route is a pre-determined flight path).
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### Re: Relative aging, a alternate relativistic method

ralfcis » 13 Mar 2017, 12:56 wrote:The doppler shift ratio is ttx/t'rx = sqrt((c+v)/(c-v))

Ralf I have told you above that this is not the doppler shift ratio, but the Doppler ratio (or factor). See https://en.wikipedia.org/wiki/Relativistic_Doppler_effect#Motion_along_the_line_of_sight.

Doppler shift is the fractional shift in frequency, i.e. $\Delta f/f_s$; it is the same as the definition for redshift given in the Wiki. Please get your terminology right, because it will not only confuse yourself, but everybody not knowing what you are talking about.

Also, expressing the Doppler ratio as the ratio of two times is bad, bad physics, because the ratio is defined for periodic signals that have a frequency and by implication also a wavelength. Even more so when the two times are for two different spacetime events, as observed in two different inertial frames. Your bacon is marginally saved by the fact that the two events happen to be time-like separated.

Just about 100% of readers seeing ttx/t'rx will interpret that as the time for a single event given in two frames, i.e. just as relative time dilation, expressed as gamma (i.e. the last formula in the OP).

Apart from these problems, the thread has merit, so please try to rescue it by being more consistent in terminology and physics.

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### Re: Relative aging, a alternate relativistic method

More completely inconstant statements:
ralfcis » 13 Mar 2017, 12:56 wrote:ttx/t'rx = Y(c+v)/c when considering the TV image speed the moving perspective sees of the stationary frame and

trx/t'tx = Y(c-v)/c when considering the TV image speed the stationary perspective sees of the moving frame.

How can a time ratio be the "speed the stationary perspective see"?
Please do not try to defend such inconsistencies, just write it to be consistent with scientific concepts.

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### Re: Relative aging, a alternate relativistic method

Sorry doppler ratio. 1/t =f so why can't I use t? When I get into the STD's I can't use f because there's only t to work with. I use the formulas as a fancy form of time dilation. When 1 frame transmits something at time t or t' (depending on whether it's the stationary or moving frame), the other frame receives it at t' or t at the other end of the 45 degree line of light. I choose one perspective but it works equally well from the other. I don't need both perspectives to validate who ages slower when a velocity change is made because when either one makes a change, they are the ones aging relatively slower whether they were deemed stationary or moving.
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### Re: Relative aging, a alternate relativistic method

There are 3 controls on a DVD player: play. fast forward, slow motion. Those are image speeds. Play is the normal time component when either the frames are not moving through space relatively to each other or proper time rate within a frame. The doppler ratio =1. Fast forward is the time component when the frames are moving towards each (doppler ratio > 1) other and slow motion is when they're moving apart (the doppler ratio is less than 1).
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### Re: Relative aging, a alternate relativistic method

P.S. I really thought you would shut me down based on my distance markers method because that's how I've been defining absolute space. I guess you have a different definition.
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### Re: Relative aging, a alternate relativistic method

No, I haven't got as far as your distance markers yet, I first want you to get the physics right.

Yes, your "TV picture" method where each participant sends a regular time-stamped signal to the other can be used to determine the reciprocal Doppler ratio, because the time between the signals represents the period (T=1/f) of a periodic signal. But T is not the time on a spacetime diagram, because it is a constant for a constant relative speed. On a STD, the ratio is determined by the relative speed and the constancy of the speed of light and obviously those two gives you a specific Doppler shift. I think you should reconsider your wording on all that.

As far as your "network of ly markers dispersed throughout the universe that are stationary wrt distances established by supernova markers relative to the earth" is concerned, it is just another inertial frame. You are free to have three frame to work in, it does not change any of the validity. But, for it to be a 3rd frame, both of your participant must be moving relative to that frame, so you accomplish nothing - you really just complicate matters.

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### Re: Relative aging, a alternate relativistic method

BurtJordaan » March 13th, 2017, 2:17 pm wrote:
Yes, your "TV picture" method where each participant sends a regular time-stamped signal to the other

As far as your "[i]network of ly markers dispersed throughout the universe that are stationary - you really just complicate matters.

I had intended that my TV broadcasts are continuous images of daily life, time stamped with the atomic clock readout. The frequency you would detect would be from the motion picture speed of the participants and clock readout relative to the receiver's normal motion speed inside their respective frames.

Anyway we'll get into the specifics of how this will be incorporated into STD's once I start posting them.

Classic relativity would have each participant's network of clocks spread throughout the galaxy. I really don't even need a network of distance markers as everyone going out into space would have a destination in mind. I don't even really need intelligent distance markers that would take into account earth's motion relative to them because that error would diminish over longer trips. The accuracy of the markers could decrease as distance between them and the earth increases.

So I'm curious, how does this network of distance markers differ from having an absolute reference space?
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### Re: Relative aging, an alternate relativistic method

Ralf, the mumbo-jumbo that you wrote above sounds like you want to establish an Earth-centered inertial frame (ECIF). If "... everyone going out into space would have a destination in mind", you need a frame for them to have coordinates for the destination. Otherwise 'destination' is meaningless, even in a Ralfitivity sense. And you know as well as I do that the ECIF is not an absolute frame...

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### Re: Relative aging, an alternate relativistic method

No, only for my coming examples. I could change the examples to be solely inside the LHC if you perfer. Every spacetime path needs a start and a finish separated by either time or distance. That's all I'm setting up. I'm not setting up anything like referencing everything relative to the CMB.
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### Re: Relative aging, an alternate relativistic method

I had hoped to write this all in one shot but my current workload until August will only allow me a few minutes per day to dribble this in. Until it's complete there will be questions that I'll have to defer until I get to write the relevant part. Some I will be able to answer right away but I can't chase after the ones that will be answered later.

The only course I took on relativity was from Brian Greene so whenever I say "according to relativity" I'm really saying "according to Greene". He said SR deals primarily with constant relative velocity no-gravity inertial frames. Everything is normal within these frames: time, space, physics experiments. SR does not apply to anything outside this baseline, specifically, if relative acceleration happens, SR somehow no longer applies (but yet it does because under certain circumstances, acceleration is the cause of relative aging which is a part of SR). I found it too difficult to keep track of what circumstances acceleration caused relative aging and under which it didn't when, in fact, under most it didn't even cause time dilation.

So instead, I adopted the perspective of how relative aging explains relativity rather than how relativity explains relative aging. I took an analogy right out of general relativity to guide my perspective. If the sun could be knocked out of its position in space like a billiard ball, the earth wouldn't know for 8 minutes that the sun was presently gone. Due to the fact that nothing can travel faster than light, we would continue our orbit as if the sun was still there. If the sun wasn't really there, then what is reality? The answer is reality and the information about that reality are the same thing. We wouldn't experience the reality of the sun no longer being there until the information that the sun was no longer there had reached us.

The same is true for relative aging. Acceleration causing it or not under so many conflicting scenarios was not a reason for relative aging. But what really causes it and under what circumstances? The answer is the same as for the sun disappearing example I gave. When two participants share the same relative velocity and one changes, the reality of that change will be delayed back to the other. The reality is they would no longer be going at the same relative velocity until the delay between them had been overcome. That speed imbalance during that interval needs to be compensated for. Relative aging, (slower relative aging for the initiator of the change) is the compensation for that speed imbalance during the speed of light delay for the transfer of information between the two. The rest is just algebraic proof of this perspective and how it's supported by relativity.
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### Re: Relative aging, an alternate relativistic method

Ralf wrote:He said SR deals primarily with constant relative velocity no-gravity inertial frames. Everything is normal within these frames: time, space, physics experiments. SR does not apply to anything outside this baseline, specifically, if relative acceleration happens, SR somehow no longer applies (but yet it does because under certain circumstances, acceleration is the cause of relative aging which is a part of SR)

SR handles acceleration just fine, but as Green said, it is not as simple as the inertial case.

Besides, there isn't really a thing like 'relative aging' in SR, at least not in the way that you describe it. The "relative' in SR means it is reference frame dependent and the difference in aging, as described in the 'twins paradox' is not a relative thing; it is absolute, meaning all frames agree.

You are right on the fact that the absolute difference in aging of the twins cannot be decided instantaneously at turn-around. They must either get together again, or they must wait until the absolute difference can be established by communication. But you are wrong in saying that the aging difference happens only during the communication delay (or because of it). It happens because of the change of inertial frame and that event converts the reciprocal time dilation up to that time into an aging difference. This is true irrespective of who knows about it, or not.

The science behind it is the invariance of the spacetime interval, a principle that you know about, but for some reason resist embracing. But don't give up, maybe all the wrong paths will eventually lead you to the right one.

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### Re: Relative aging, an alternate relativistic method

It happens because of the change of inertial frame and that event converts the reciprocal time dilation up to that time into an aging difference.

Well I hope you allow me on here long enough to show what my math says about this. If I interpret what you say correctly, you're saying all that backlogged time dilation converts into relative aging due to a velocity change and a coming together either physically or through a communication completion. Even though this is coincidentally true, I hope to show you some surprising results where relative aging is a phenomenon independent of time dilation. We had this discussion before and when I said it was a conversion, you said I was dead wrong. Now it seems we've switched polarities. But we'll have to wait on settling this.
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### Re: Relative aging, an alternate relativistic method

I just want to mark your statement in a short post so I can find it again when I'm ready to come back to it:

It happens because of the change of inertial frame and that event converts the reciprocal time dilation up to that time into an aging difference.
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### Re: Relative aging, an alternate relativistic method

Besides, there isn't really a thing like 'relative aging' in SR, at least not in the way that you describe it. The "relative' in SR means it is reference frame dependent and the difference in aging, as described in the 'twins paradox' is not a relative thing; it is absolute, meaning all frames agree.

Potato tomato. Of course it's absolute because the effect persists after the two meet up in the parking lot and drive home. But how I mean it is one ages relatively slower than the other. I use a different method than classic relativity to determine which one. That's the purpose of this thread.
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### Re: Relative aging, an alternate relativistic method

ralfcis » 15 Mar 2017, 21:10 wrote:If I interpret what you say correctly, you're saying all that backlogged time dilation converts into relative aging due to a velocity change and a coming together either physically or through a communication completion.

No, you are still misinterpreting what "relative" means in SR. It 'converts into', 'becomes' (or whatever semantics suits you) an absolute elapsed time difference, not into a "relative aging". And it does not depend on a coming together or a communication, just on a return to the same inertial frame, even if it is momentarily.

Yes, observations from a distance will take time, but everyone (except Ralf, it seems) will eventually agree that at that moment, the one who has changed frames has aged less between the two events (flyby and turnaround). And as you know, the acceleration itself did not cause the difference, so what did?

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### Re: Relative aging, an alternate relativistic method

ralfcis » 15 Mar 2017, 21:56 wrote: I use a different method than classic relativity to determine which one. That's the purpose of this thread.

Fine, but do not use principles incompatible with 'classic relativity' to defend your method.

For the record, if we have ever used the term "relative aging" in the past to mean "absolute aging difference", it was a mistake and let us not repeat that. "Relative aging" in SR would mean "I view you as aging slower, but you view me as aging slower". I do not recommend such semantics anyway.

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### Re: Relative aging, an alternate relativistic method

Ok I'll call it aging difference, I just don't want to get kicked off on any technicality. Thank you for taking the time to keeping me on track.

But if I may say, the real difference between the methodologies is mine attempts to shed light on the nature of reality itself with far reaching implications for all of physics while the classical method is able to calculate values for aging differences. Anytime it can't arrive at the correct value, it disqualifies those errors as being outside the rules of where aging difference is valid. My method can calculate the same aging difference before the end of the spacetime interval regardless of perspective which relativity deems as invalid because its value for aging difference before the end of the spacetime interval is dependent on perspective.

I know, the first rule of relativity is that relativity is always right, but if you do happen to find a legitimate problem with it then you're having a devil of a time grasping the first rule. Ok, back to being a good boy, I do not want to be shut down again. I'm just here for a dry presentation of relativistic mathematics.

P.S. I'll show I can prove a degree of aging difference even if the frames do not return momentarily to a common stationary reference frame. Will I be disqualified because relativity can't do that. It indeed can, it just doesn't realize it yet. We are going to have a long few months here.
Last edited by ralfcis on March 15th, 2017, 6:28 pm, edited 1 time in total.
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### Re: Age of Enlightenment

I still prefer the term "aging" as it takes the focus off clocks as being somehow special. I agree that observers in different inertial frames will find each other's aging to be mutually* decreased.

BurtJordaan wrote:...the one who has changed frames has aged less between the two events (flyby and turnaround). And as you know, the acceleration itself did not cause the difference, so what did?

I got confused here. The first part is true. Are we not defining acceleration (a) as a = Δv/Δt ? A change of frames would seem to imply acceleration relating to an applied force.

I don't imagine you are denying that acceleration is associated with decreased aging.

In one book (of many), the twins of the paradox are acknowledged to experience mutually decreased aging while at constant velocity. But for the frame changing twin: "During the turn around, which requires two weeks for Veronica, the earth clock jumps ahead by 12.8 years!"

Of course, in this scenario, earth is not accelerating (changing inertial frames). It is Veronica (and here rocket exhaust) which, under equal and opposite forces, are accelerating. That caused Veronica to dramatically slow her aging relative to earth (and anything else not accelerating as much).

*"reciprocal" is a legitimate term but might conceivably be confused with the mathematical meaning (1/n).

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### Re: Relative aging, an alternate relativistic method

Umm I'm going to let Jorrie handle this but your use of terms is imprecise. He's the terms guy.
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### Re: Relative aging, an alternate relativistic method

ralfcis » 16 Mar 2017, 00:13 wrote:But if I may say, the real difference between the methodologies is mine attempts to shed light on the nature of reality itself with far reaching implications for all of physics while the classical method is able to calculate values for aging differences. Anytime it can't arrive at the correct value, it disqualifies those errors as being outside the rules of where aging difference is valid.

These sort if statements will get you kicked off the Physics stage.

P.S. I'll show I can prove a degree of aging difference even if the frames do not return momentarily to a common stationary reference frame. Will I be disqualified because relativity can't do that. It indeed can, it just doesn't realize it yet. We are going to have a long few months here.

It'll be great if you can prove that, but good luck!

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### Re: Age of Enlightenment

Faradave » 16 Mar 2017, 00:27 wrote:
BurtJordaan wrote:...the one who has changed frames has aged less between the two events (flyby and turnaround). And as you know, the acceleration itself did not cause the difference, so what did?

In one book (of many), the twins of the paradox are acknowledged to experience mutually decreased aging while at constant velocity. But for the frame changing twin: "During the turn around, which requires two weeks for Veronica, the earth clock jumps ahead by 12.8 years!"

Yes, this is sometimes used in more advanced courses, where students already know some GR and the differences between local and global observations in the presence of gravity. Mostly as in "the twin paradox revisited". They then already understand the caveats required for such a statement (like hypothetical uniform gravitational field), without any being stated. I think it is a bad idea for teaching beginners in SR.

For beginners, I prefer the all-inertial, time hand-off scenario with Alice, Bob and Charlie. The same three events for the "round trip", just so much easier to analyze.

As far as "reciprocal" vs. "mutual" aging is concerned, yea, semantics always remains an issue in science. I think "reciprocal aging" is used in the sense of "reciprocate", which is quite applicable, but I'm no linguist.

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### Re: Relative aging, an alternate relativistic method

Re: Relative aging, an alternate relativistic method
Post by BurtJordaan » March 16th, 2017, 1:55 am

ralfcis » 16 Mar 2017, 00:13 wrote:
But if I may say, the real difference between the methodologies is mine attempts to shed light on the nature of reality itself with far reaching implications for all of physics while the classical method is able to calculate values for aging differences. Anytime it can't arrive at the correct value, it disqualifies those errors as being outside the rules of where aging difference is valid.

These sort if statements will get you kicked off the Physics stage.

1. The first statement is just an extrapolation from the general relativity vanishing sun thought experiment. GR does not interpret it as reality being delayed by the speed of light delay? If it happens in GR, why am I out of bounds to infer a similar possible scenario for aging difference?

2. When you analyze a spacetime path at .6c 3ly roundtrip from both perspectives using reciprocal time dilation, Alice and Bob will have different per year aging differences during the 2nd half of the trip. Because of this inconsistency, relativity precludes making any interim determinations about the aging difference between the two, it can only be done at the end because that yields the correct answer. If the two analyses yielded the same per year aging difference after Alice changes velocity, would there be any need to wait for the end of the spacetime path before being able to make an age difference determination?

The doppler ratio method I use does not have this inconsistency between the two perspectives, Alice ages slower the same way from both perspectives before the spacetime path ends. To me this means there is no deeper reason for relativity declaring that aging difference can't be determined before the end of the spacetime path, no? Perhaps we should get into this after we get into some STD's.

P.S. Another way to look at what I'm saying is consider Alice either stops or continues going at yr 6. Her aging difference from Bob up until the 6 yr mark should be unchanged by what she does at the 6 yr mark. Of course every subsequent change will alter the final result at the end of the spacetime path but I'm saying each change contributes a fixed amount to that total regardless of perspective or subsequent changes.
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### Re: Relative aging, an alternate relativistic method

Ralf, I think we essentially say the same thing, just using different semantics, so I'll cut you some slack until you come up with your full solution. No further inputs from me until that time, provided that you do not tarnish the good name of this Physics section... ;-)

PS: I have overlooked this wrong statement of yours:

Because of this inconsistency, relativity precludes making any interim determinations about the aging difference between the two, it can only be done at the end because that yields the correct answer.

In SR, the interim solution is known as soon as the frame change has been done. I have said so repeatedly in the past. SR is critically dependent on inertial frames, so "is known" means "known in all inertial frames". Obviously, not every observer in every inertial frame can know immediately, but that is never the point, or a problem in SR.

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### Re: Aging Difference, an alternate relativistic method

Yes you did state all the backlogged time dilation becomes an immediate age difference the instant a frame change occurs. Yes I get a different mathematical result. I have shown that if the frame change is near instantaneous, like a brief stop and then restart at the previous speed and direction, that age difference does not suddenly get heaped on all at once. I get almost no aging difference in this scenario.
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### Re: Relative aging, an alternate relativistic method

OK, but I say you are wrong; so go ahead and proof your statement.

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### Re: Relative aging, an alternate relativistic method

Good, we have something falsifiable for when we get there.
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### Re: Aging difference, an alternate relativistic method

So sorry for the delays but I'm just swamped with work. I have been working on the math to reconcile the classic relativistic approach to aging difference using reciprocal time dilation and this approach using doppler ratio. I make so many arithmetic errors (like (4/3)/2 = .8) which really slow me down. But I have noticed the cause of the discrepancy between the two methods. Time is dual in nature, it is both a point and a wave. Classic relativity concentrates on the coordinate side of time while the doppler ratio deals with the wave or rate of flow nature.

For example, Alice leaves Bob at .6c relative velocity. When Bob sees Alice is at 1.25 yr, .75ly, Alice's coordinates for that point in spacetime are (1, .6). Classic relativity is all about coordinate transforms. The doppler ratio would concentrate on the TV image speed, that each would see of the other, as going half the normal speed, slow motion. In terms of light signals from each other, the frequency would be seen as half.

That's because the wave nature of time itself is being stretched. The different nature of the doppler effect for light as opposed to sound is that the medium for light has no velocity (as discussed in the thread, "can a vacuum have a speed"). Red shift for light is an indication that relative motion (whether the source or receiver is deemed moving) slows time thereby stretching the wavelength of the light between the two. The doppler effect for sound is only due to the movement of the source or the receiver relative to the medium or the movement of the medium because the medium for sound CAN have a velocity.

The speed of sound,however, is relative to the medium and can't be influenced by the speed of the source just like it is for light. But unlike for light, the source or receiver can have a relative velocity to the medium and therefore a relative velocity to the speed of sound. For light, the relative velocity for source or receiver is always the speed of light. This is not due to a special wave nature for light but due to the fact that the speed of light just happens to be the universal speed limit for any relative velocity.

Yes this is quite a radical interpretation; I'm wondering if those who understand the doppler effect (some on this forum have no clue) see anything wrong with it.
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