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#29697 03/06/09 11:49 PM
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Binary stars and light speed

I want to revive a old astronomical dispute about light speed and binary star system.

For present discussion two sources are used as reference:
http://www.datasync.com/~rsf1/desitter.htm
http://www.elkadot.com/relativity/Binary%20systems%20and%20light%20speed%20variability.htm

The basic ideea for a new interpretation of binary star system period is related to a new concept: temporal abberation.
When succesively a star cover another in such system, depending on stars relative speeds (related to Earth observer), the photons are travelling with different speeds.
Therefore further away is such system, smaller is the ,,apparent" period of revolution.

Sorin Cosofret

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Lights speed is constant relative to the observer. So light from a star moving towards us moves at the same speed as light front a a star moving away from us.

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As Stereologist said, the speed of light is independent of the motion of both the source and the observer. Light waves from a receding object are stretched, and so are longer, and therefore 'shifted' toward the red end of the spectrum. Conversely, light waves from an approaching object are compressed, and so are shorter, and therefore 'shifted' toward the blue end of the spectrum. But whatever the wavelength - whatever the energy - and whatever the relative motion of source and observer, the velocity of the photons relative to the observer is the same.

We should remember that Special Relativity was proposed in 1905. It's counterintuitive now, and was no less so then. No surprise then if we find that alternative proposals either pre-date it, or attempted to refute it.

It could be that I've missed your point, sorincosofret. If so, by all means have another shot at it smile


"Time is what prevents everything from happening at once" - John Wheeler
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Originally Posted By: stereologist
Lights speed is constant relative to the observer.
If it would be constant, we shouldn't observe a gravitational lensing - or not?

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Not sure why you say that? What does light speed have to do with gravitational lensing?

When we talk about the speed of light we mean in a vacuum. Light travels at different speeds in different mediums. The speed of light is constant for all observers. That in no way means that light can't be bent.

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Originally Posted By: stereologist
When we talk about the speed of light we mean in a vacuum. Light travels at different speeds in different mediums. The speed of light is constant for all observers. That in no way means that light can't be bent.

Absolutely, but to clarify a point about relativity that might be confusing to some: in the case of gravitational lensing, it's the space which is bent, and the light continues to follow the shortest path through it, known as a 'null geodesic'.


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Originally Posted By: stereologist
..When we talk about the speed of light we mean in a vacuum....The speed of light is constant for all observers.
If speed of light in vacuum is constant for every observer, how is it possible, light is moving through vacuum around massive objects in different speed - so it's bended around?



Have you ever thought about these textbook sentences - or are just parroting them like Bibble?

Originally Posted By: redewenur
..in the case of gravitational lensing, it's the space which is bent...
Come on - everyone can see, it's just a path of light, what is bending here - not some space-time, which even nobody did ever see.

You're like people, who are saying: well, Sun "may" appear shinning for someone - but in fact it's absorbing darkness, cause relativity says so. Do you consider, I have no eyes?

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"Do you consider, I have no eyes? "

Here's the thing, Zeph. Scientists don't have to convince you. And they're not even trying to convince you. As confusing as this may seem to you - they don't even care what you think, the vast majority are not even aware of your existence.

Do you have a reference that says that speed of light is not constant in gravitational lensing?

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"Have you ever thought about these textbook sentences - or are just parroting them like Bibble?"

I don't know about anyone else. Actually, I have thought about this stuff a bit - just the constant C and not the grav lensing. I don't spend a lot of time on it, either at a time or cumulatively. To a certain extent, yes, I am parroting it. There are things I don't understand, but I don't assume that I'm a great genius just because I don't understand every thought of the scientists and mathematicians. I also don't assume that they're all idiots.

I can at least follow part of what they're saying. I can't follow what you're saying at all.


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Originally Posted By: Zephir
Originally Posted By: stereologist
..When we talk about the speed of light we mean in a vacuum....The speed of light is constant for all observers.
If speed of light in vacuum is constant for every observer, how is it possible, light is moving through vacuum around massive objects in different speed - so it's bended around?


Come on - everyone can see, it's just a path of light, what is bending here - not some space-time, which even nobody did ever see.
Very well said TFF. Thanks.

I'm not a physicists either, but I have played one on TV... wink
...I like to call it Integrative Science.
===

Zyphir,
I wish I had your abilities with the graphics. I'm assuming these are your creations; but even if not, I'd like to suggest that those curving red lines travelling around the "black spot" are not drawn correctly (if they're supposed to mirror reality).

The upper (outer) red line should veer out to the right, farther away from the center of the black spot relative to where the inner red line ends up. ...maybe that is not explained very well....
The red lines should diverge from each other as they veer around the massive object, with the inner line being closest to remaining a perfect circle, and the outer line appearing more parabolic.
The lines shouldn't remain parallel, but be farther apart after passing by the object--"stretching" the image.

It may then seem as if the speed of light is different for these two red lines, but you need to recall that times runs faster for the outer red line (when it is curving) than for the inner red line--as it curves.
...or is it easier to visualize by defining time as moving slower for the inner line?
...so while light is travelling at the same "speed" --the inner red line travels less far than the outer line--in the same amount of "time."

...but the two lines do travel the same amount (still the same speed), after covering the same amount of spacetime.

Problems usually arise when we examine space or time individually--without the other component included.

~ nez pas?


Pyrolysis creates reduced carbon! ...Time for the next step in our evolutionary symbiosis with fire.
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Originally Posted By: TheFallibleFiend
..the vast majority are not even aware of your existence..
LOL. Can you prove it? If not, why I should believe you?
Originally Posted By: TheFallibleFiend
..do you have a reference that says..
What are you calling "a reference"? Are u capable to understand, what the "bending" means? Can you illustrate it in different way, then like the motion along "different trajectories between point A and B"? If not, why I should believe you?
Originally Posted By: TheFallibleFiend
..to a certain extent, yes, I am parroting it...
Can you prove, some other "extent" exist? Can you understand the feeling of people, who were blamed & manipulated by some sectarian society for whole their life? It's just your situation, my dear, face it.

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Originally Posted By: samwik
I'd like to suggest that those curving red lines traveling around the "black spot" are not drawn correctly..
You're right, but I'm not illustrating a gravitational lensing, but a bending concept as such by now. We can use some drawing of gravitational lensing, as presented by mainstream science, instead. But these drawings are often designed to hide conceptual problem of lensing phenomena purportedly.



Originally Posted By: samwik
The lines shouldn't remain parallel, but be farther apart after passing by the object--"stretching" the image..
Yes maybe - but it still doesn't change the point, no radiation can move between two points along different paths, if it's not able to move in different speed through space at the same time. Briefly speaking, invariant light speed contradicts the gravitational lensing phenomena in every aspect of it. But it basically means, gravitational lensing IS NOT relativistic phenomena - despite the fact, relativity can compute it in high precision. Such situation is nothing new in physic. For example the motion of stars and planet was explained or even predicted in high precission by using of geocentric model before years - although we know very well by now, it wasn't geocentric phenomena at all. This situation just repeats again by now at another level of human understanding. And the fact, we didn't recognize our mistake for so long time is just another relativity phenomena.

I presume, you know about AWT explanation of this apparent paradox.

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Originally Posted By: Zephir
...no radiation can move between two points along different paths, if it's not able to move in different speed through space at the same time.
That certainly seems obvious--like "common sense."
But....

What you say would be true if "time" was invarient over the course of the different light paths, but time goes slower for the inner (shorter) path. Velocity = distance/time. Or, V=d/t. As d is measured on the shorter path, so too is time slower on that path; thus Velocity (of light) remains constant. Or for the longer, outer path, time moves faster so that V again remains constant--the ratio of d/t remains constant.
To sum up: Longer/quicker = Shorter/slower.

And that's one point of relativity--that time operates differently in different places (i.e. different locations within a gravitational fields).

Realize that "d/t" is roughly the same as saying "space divided by time" or "the ratio of space to time."
===

But you're right about me not knowing about the AWT explanation for lensing. Can you point me to a link, or give a short explanation? ...and I'm sorry if it's earlier in this thread--just point....

In the past I have read your earlier posts about AWT, and I naturally appreciate the AWT idea; it is very similar to my intuitive sense of reality--and beyond.
AWT is a good metaphor for thinking about reality, as well as a possibly useful framework for relating many different phenomena; but I think that standard metaphors and frameworks currently allow us to apply many different mathematical transformations well enough to get by these days.
Perhaps a better intuitive understanding (AWT) would lead to a wider and more effective application of mathematical translations of reality, but until you can find a way of expressing AWT mathematically, I think AWT will only help people to intuitively see the overall connectivity of reality (and beyond), and try to seek for those mathematical connections.
...or words to that effect. smile

In order to promote AWT, other theories don't need to be wrong.
Do you see relativity as wrong, or do you see AWT as refining relativity (in the way that relativity refines mechanics)?

~ wink

p.s. Do you see my point about time operating differently (if the speed of light is constant)?


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Originally Posted By: samwik
...time goes slower for the inner (shorter) path...
Well - but did we ever measure the time here? Isn't such reasoning of reality based on relativity itself, thus being a circular reasoning?
Originally Posted By: samwik
...AWT explanation for lensing. Can you point me to a link...

Indeed, you can read about it here, for example..
Originally Posted By: samwik
... I think AWT will only help people to intuitively see the overall connectivity ...
The situation was quite similar at the time of heliocentric model introduction. The geocentric model enable to compute nearly anything, what the astrologist and astronomers needed for predictions of path of planets, the dates of conjunctions and solar or lunar eclipses.

Heliocentric model was useless for practical purposes in the times of Galileo. Astronomers didn't know the gravitational constant (it was measured first in 1798). They didn't know about mass of planets, so whole centuries the heliocentric model was useless for science computations. Everything what the heliocentric model was able to do was just a explanation of some sparse observations of subtle phenomena: order of Venus phases, some crater shadows on the Moon. It's apparent, heliocentric model was useless for science, so many scientists have refuted it by the same way, like Holy Church.

Does it mean, heliocentric model is insignificant? If yes, why we don't learn about geocentric model and epicycles by now? Epicycles and deferents were much more useful for formal theories of Galileo time.
Originally Posted By: samwik
...until you can find a way of expressing AWT mathematically...
You can model AWT mathematically in approximate way - but it's targeted to computer simulations, not for some formal math games, being particle model of reality. I can say as well, until string theory is not able to compute some observable quantities, the science has no reason to bother with it.

But it does so for last forty years! And AWT is only two years old. You can believe me, you would be very disappointed by state of string theory in 1970 - only few mathematicians did knew about it that time.


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