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Author Topic:   Speed of Light
Alfred Maddenstein
Member (Idle past 1379 days)
Posts: 565
Joined: 04-01-2011


Message 241 of 268 (615565)
05-14-2011 11:17 AM
Reply to: Message 231 by Viv Pope
12-31-2009 8:27 AM


Re: c & t
Viv Pope writes:

To Iblis,
You ask why does this happen? Or doesn't it?

Well, Iblis, it doesn’t. In my last post to Cavediver, I described what I have called the Cinematic Model as a logical solution of the ‘two velocities’ problem in relativity, on the existence of which – the two velocities – he and I concur. (see his Message
222. My reply has been sent but hasn’t appeared yet.)

So, let’s ‘chalk this up’ as a positive move forward. Now you say you want to know the ‘substance’ of the argument. Well, okay, here goes.

Your knowledge of the existence of the sun begins with a pattern of quantum light pixels in your eye – or, more safely, in something like a camera or a projected image. Now it has to be faced that in no way whatsoever can you see those light quanta starting out from the sun and travelling for eight minutes in space before entering your eye – or the camera.

Now hold that thought. Then think: From where did I get the idea that those ‘photons’ which enter my eye have ‘travelled for eight minutes’? Certainly it was not from observing those ‘photons’ travelling in that way. So that notion of the ‘space- travelling photons’ is a theory, no less.

And what about the distance of the sun? How do you know that? The simple answer is, of course, that you were told it or that you read it somewhere. Again, in no way can you actually see that distance stretching from you to the sun. So, from where do we get the knowledge that the distance from here to the sun is 93 million miles? Did someone tape-measure it or determine it in some other ‘hands-on’ way ? Well, of course not! So, again where did that knowledge come from?

You wanted the ‘substance’, well, now you’ve got it. What is not substantial, indeed is completely insubstantial, is the idea of light travelling in the form of ‘photons’ from the sun to you. As you have already realised, the set of quantum pixels that occur in your eye are the same events, identically, as those in certain atoms on the sun. As we discussed earlier, this is exactly the same as saying that the sun and its distance from you are projections out of statistical numbers of these single, discrete events common to both you and the sun. In my previous posting you seemed not to have been able to complete that conceptual flipover from the insubstantial ‘light in space’ to the substantial ‘space in light’ which is the point of departure for a whole New Physics, based on the ideas of Einstein’s relativistic mentor, Mach, instead of those of his pupil, Einstein, which he, Mach repudiated. Forgive me for saying this, Iblis, but that bit of logical ratiocination seems to have gone right over your head – as, indeed. it does with most people confronted with that logical argument, steeped as they are in the now failing extant physics which regards light in space as substantial.

Let’s face it, then, the substance of this issue is that our knowledge of the sun’s distance comes from nowhere but the patterns of quantum pixels in our eye or some other optical instrument – or, of course, in the eyes or instruments of other observers, some of whom are the expert observers whose observations and measurements are the basis of our textbook knowledge of physics and astronomy.

Characteristic of these informational patterns of quantum pixels are, of course, the phenomena of parallax and perspective, from which the positions and distances of external objects are automatically deduced. As I described it to Cavediver, these patterns are analogous to the still photographs, or ‘stills’ in a cinematographic projector, and the ‘action’ of the film, as the director views it, consists of sequences of these patterns of quantum stills in the time of the observer of that action. The objects are instantaneously connected in the stills themselves while they move with finite speed relatively to one another in the running of the film. (Compare this with what I discussed with Cavediver.) In this Normal Realist Cinematic Model of quantum connection, there is no conflict whatsoever between instantaneous and delayed distant interaction.

So there is no relationship between the two places which, as you say ‘exists and then collapses’. Nor is there any ‘duration element’ which, from the viewpoint of the observer ‘seems to take no time at all’. And, certainly, there is no ‘proper time and relative duration reversal’. For anyone who can shake his mind free of conventional precepts, no such puzzles arise.

Viv Pope (no pseudonym).


That's very interesting- all that you are saying, Viv Pope. Certainly the two different approaches could compete and co-exist. There is no need for dogma.
Space in light makes as much sense as light in space. Velocity of light is indeed the receding speed limit and the velocity of horizon.
This message is a reply to:
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David Carroll
Junior Member (Idle past 1645 days)
Posts: 12
From: Fairmont, West Virginia, USA
Joined: 08-22-2012


Message 242 of 268 (671346)
08-24-2012 1:01 PM
Reply to: Message 241 by Alfred Maddenstein
05-14-2011 11:17 AM


Re: c & t
What about this: What if the speed of light ("c") originally was much faster than it is now, but at the moment of change to a slower constant, all the light that was already in transition were "grandfathered", as it were? Thus, light coming now from sources billions of light-years away is light traveling at a much more dramatic speed. This is because the light would have been emitted from the sources before the change in "c" occurred, but because it was already in transition before that change, its speed was grandfathered.

And then wouldn't this account for the red-shift? If c were faster, then wouldn't the space dimension parallel to the direction of the faster-c light-beam undergo a Lorentzian expansion/dilation? (Since, if c were faster, time by definition would undergo a negative dilation, i.e. a positive time-contraction....and to preserve the geometry of the spacetime frame belonging to this faster-c light beam, a negative Lorentzian contraction, i.e. a positive Lorentzian expansion/dilation, would have to result). This Lorentzian expansion would flatten out the light-wave, causing its energy to shift to the red. Or, another way of putting it, since a faster c would result in a higher momentum (everything else being equal) for the photon in question, the energy required to make a photon go faster would have been "taken" from the energy of the wavelength in order to preserve conservation of energy, producing a red-shift for that photon.

Any thoughts?


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David Carroll
Junior Member (Idle past 1645 days)
Posts: 12
From: Fairmont, West Virginia, USA
Joined: 08-22-2012


Message 243 of 268 (671351)
08-24-2012 1:18 PM
Reply to: Message 242 by David Carroll
08-24-2012 1:01 PM


Re: c & t
I also have a more general question. I could "propose a new topic" for this, but it really does relate to the question of the Speed of light, even if it doesn't necessarily touch on questions of Creationism (at least not yet).

Does the force of gravity weaken in frames approaching c?

Imagine a spaceship moving very fast, very close to the speed of light (c). Also, this spaceship is so large that it contains two objects the size of our own moon. Now, according to the laws of relativity, the masses of the two moon-sized objects increase relative to a stationary observer. But also, because of time-dilation, closing movement between these two objects would be slower to a stationary observer than it would be to those on board. Moreover, if the direction of the mutually attractive movement of the two moon-sized objects were parallel to the velocity of the spaceship, the Lorentzian contraction would cause the movement apparent to a stationary observer to be even slower. But, from my stationary point of view, this should NOT occur. If the masses were larger, then the gravitational pull between the two objects would be larger, resulting in a faster mutually attractive acceleration of the two objects. But from my binoculars, I don't see this. I see attractive movement much, much slower than it should be from my point of view, especially considering that the masses have increased.

Therefore, shouldn't the gravity field for an object of given rest-mass DECREASE as it approaches c?

Sorry to pose questions that are probably elementary to most of you. I am not a professor, or even a student (at least not formally) of physics, so these questions are new and original in my own mind (though I'm sure not in reality). The little physics I have is from my Navy nuke days (and a little pop-science reading). Any answers would be appreciated.


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Stile
Member
Posts: 2870
From: Ontario, Canada
Joined: 12-02-2004
Member Rating: 2.6


(1)
Message 244 of 268 (671357)
08-24-2012 1:42 PM
Reply to: Message 242 by David Carroll
08-24-2012 1:01 PM


Re: c & t
David Carroll writes:

And then wouldn't this account for the red-shift? If c were faster, then wouldn't the space dimension parallel to the direction of the faster-c light-beam undergo a Lorentzian expansion/dilation?

Perhaps. But a larger, simpler problem is created.

If "old light" is grandfathered to be faster-c, and "new light" is a slower-c... then we should be able to measure a difference between the c on new light from a lightbulb turned on here on Earth vs. the c on old light coming into Earth from far away stars.
But... I don't think a difference is measured.
In fact, I think that the two speeds of light (and any other attribute of the new vs. old light other than age) are exactly the same.


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 Message 242 by David Carroll, posted 08-24-2012 1:01 PM David Carroll has responded

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David Carroll
Junior Member (Idle past 1645 days)
Posts: 12
From: Fairmont, West Virginia, USA
Joined: 08-22-2012


(1)
Message 245 of 268 (671429)
08-24-2012 11:59 PM
Reply to: Message 244 by Stile
08-24-2012 1:42 PM


Re: c & t
But from what I understand, the speed of light can be measured only if the transmitter and the receiver are both laboratorically at hand. We would need to know both that the source is "d"-distance away from the receiver and that the receiver intercepted the photon at "t" time after the transmitter emitted it. The only thing we can know about a photon, whose "transmitter" is not at human hand, is its energy/momentum (or its position within the matrix of the intercepting mechanism, of course, but that's irrelevant here). But its energy could mean a number of different things: if it has a blue wave-length, it could mean that the excitation energy of the transmitting reaction had an energy equivalent to just that amount of blueness at rest....and that, therefore the transmitting source is at rest relative to us. It could ALSO mean that the excitation energy of the transmitting source was more to the red, but that source is moving toward us. It could even mean that the source is moving away from us, but the excitation energy of the source was equivalent to violet wavelengths. Or - as is my contention - it could possibly mean that the speed of light has changed over time, or possibly over space.

One could make judgments about the nature of the transmitting source, but one has to be careful here. Parallax is helpful only within relatively short distances (parallax works by the same principle whereby you stare at a spot on the wall and alternately close one and then the other eye - the apparent discrepancy between the two apparent spots can be used, trigonometrically, to determine the distance of the spot from the bridge of your nose......same principle, but telescopes instead of eyes, and stars instead of spots). We could judge by the stage of development that the star or galaxy is in. But here we have to be careful too: if there is dark matter, this would certainly mess with the rate of development of a star or galaxy. And not only dark matter, but a number of other factors mess with this too: space warps associated with expanding universe, black hole singularities, or nihilarities (a pet theory I'm presently working on: I'd love to discuss it, but I'll withhold myself).

I hope this made sense. My roommate is watching stand-up comedians and it's messing with my concentration.

Edited by David Carroll, : misspelled "nihilarties". also wanted to include the word "pet".


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David Carroll
Junior Member (Idle past 1645 days)
Posts: 12
From: Fairmont, West Virginia, USA
Joined: 08-22-2012


Message 246 of 268 (671437)
08-25-2012 1:10 AM
Reply to: Message 244 by Stile
08-24-2012 1:42 PM


Re: c & t
I have also touched on this same concept of a changing speed of light in another thread (the one dealing with carbon-dating), where I touch on what a changing c would imply on the quantum level. Any "wave" is a disturbance in the field involved: a photon is a disturbance in the electro-magnetic field. But there are also waves (and associated particles) in the weak nuclear field and the strong nuclear field. Thus, a change in c would imply a change in the speed of propagation of waves in the electro-magnetic field and the weak field and the strong field. This would, in my opinion (none of this has been proven empirically.....it is indeed speculation on my part, but based strongly on a general knowledge of how physics works), result in a change of rate at which the strong field, weak field, and electro-magnetic field interact with each other. An isotope decay is a result of such interaction. If c changed, the rate of these interactions would also change.

The beauty of this hypothesis is that it would solve the isotope decay problem and the starlight travel-time problem in one fell swoop. But it needs a lot of fleshing out on my part. Plus, the gravitational field works entirely differently on a whole 'nother level from the other fields....I mean in a way vastly different than the way, say, the strong field differs from the electro-magnetic field.


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NoNukes
Member
Posts: 9547
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


Message 247 of 268 (671438)
08-25-2012 1:22 AM
Reply to: Message 245 by David Carroll
08-24-2012 11:59 PM


Re: c & t
But from what I understand, the speed of light can be measured only if the transmitter and the receiver are both laboratorically at hand.

Your understanding is not correct. As an example Roemer produced an estimate of the speed of light in 1670 by measuring the discrepancies in the observed positions of one of Jupiter's moon (Io). Neither the source of the light (the sun) or the reflecting object (Io) were accessible to Roemer.

What is necessary to measure the speed of light, is a distance to traverse, and an indication of the time for traversing that distance. The distance need not include the point of transmission.

Further, it is impossible to measure the speed of light by measuring the energy of a photon because photons always travel at the same speed. So the fact that there are multiple sources of red-blue shift is irrelevant.

if there is dark matter, this would certainly mess with the rate of development of a star or galaxy

Surely, eh? So what would be the mechanism for dark matter to affect the development of a star?

If you are interested in how the distance to astronomical objects are determined I recommend the following wikipedia article as a start.

http://en.wikipedia.org/wiki/Cosmic_distance_ladder

And you aren't working on anything like a "theory".


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

“Choose silence of all virtues, for by it you hear other men's imperfections, and conceal your own.” George Bernard Shaw


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David Carroll
Junior Member (Idle past 1645 days)
Posts: 12
From: Fairmont, West Virginia, USA
Joined: 08-22-2012


Message 248 of 268 (671440)
08-25-2012 2:05 AM
Reply to: Message 247 by NoNukes
08-25-2012 1:22 AM


Re: c & t
I apologize for using the word "laboratorically". What I meant by this word was not a literal laboratory with walls and and people in white coats, but simply a way to convey the idea that the distance between the transmitter and the receiver are pre-determined (as they would be in a laboratory, even if this "laboratory" would be our solar system). Such would be the case with the sun and Io, both of whose distances can easily be determined by parallax and luminosity without any significant factors that would fudge these. And since the light dealt with here came from the sun, whatever photos emitted from it would have our normal c (since any "grandfathered" higher-c light beams would be billions of light years away from the sun by now).

As far as dark matter goes, if we assume that dark matter has a non-uniform density distribution across the universe, which is only fair considering that we can't directly see it anyway, a star in between two masses of dark matter may, or perhaps surrounded by some halo of dark matter, would have its gravitational field something to contend with.


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NoNukes
Member
Posts: 9547
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


Message 249 of 268 (671441)
08-25-2012 3:05 AM
Reply to: Message 248 by David Carroll
08-25-2012 2:05 AM


Re: c & t
As far as dark matter goes, if we assume that dark matter has a non-uniform density distribution across the universe, which is only fair considering that we can't directly see it anyway, a star in between two masses of dark matter may, or perhaps surrounded by some halo of dark matter, would have its gravitational field something to contend with

Dark energy and dark matter don't have appreciable gravitational effects over such small distances. Motion within the solar system acts essentially according to Newtonian mechanics, taking into account only gravity as produced by ordinary matter.

You are making this stuff up. For example...

Such would be the case with the sun and Io, both of whose distances can easily be determined by parallax and luminosity.

No that is not how we determine or know the distance to Jupiter, Io, or the Sun.

but simply a way to convey the idea that the distance between the transmitter and the receiver are pre-determined

We don't need to know the location of the transmitter (sun). What is important in Roemer's experiment is knowing the difference in distances between Jupiter and earth at different times.

I ask again what is the purpose of these flights of fancy. You are making up stuff to explain what exactly? I raised the issue that we have evidence that the speed of light was consistent with its current value at a time 160000 years in the past. Carbon dating is only used to estimate dates that are within the last 50,000 years or so, which is sufficient to debunk at least some creationist estimates for the age of the earth. So when is this step change in the speed of light supposed to have happened?


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

“Choose silence of all virtues, for by it you hear other men's imperfections, and conceal your own.” George Bernard Shaw


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NoNukes
Member
Posts: 9547
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


Message 250 of 268 (671447)
08-25-2012 9:43 AM
Reply to: Message 242 by David Carroll
08-24-2012 1:01 PM


Re: c & t
And then wouldn't this account for the red-shift? If c were faster, then wouldn't the space dimension parallel to the direction of the faster-c light-beam undergo a Lorentzian expansion/dilation? (Since, if c were faster, time by definition would undergo a negative dilation, i.e. a positive time-contraction....and to preserve the geometry of the spacetime frame belonging to this faster-c light beam, a negative Lorentzian contraction

Show me the math. This looks like complete nonsense.

If the speed of light were larger then the Lorentzian effects would be less as viewed from our frame of reference. If the speed of light were infinitely great, there would be no Lorentzian relativistic effects at all. After all time-dilation and length contraction effects are related to v/c.

Besides all that, have you forgotten that you are postulating a single step increase in the velocity of light? If there is no dependency of red shift with distance, and the explanation were as you suggest, we would expect to see a single value for red-shift for all distant objects. Is that what observation reveals?

Edited by NoNukes, : No reason given.

Edited by NoNukes, : No reason given.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

“Choose silence of all virtues, for by it you hear other men's imperfections, and conceal your own.” George Bernard Shaw


This message is a reply to:
 Message 242 by David Carroll, posted 08-24-2012 1:01 PM David Carroll has not yet responded

    
Dr Adequate
Member
Posts: 15929
Joined: 07-20-2006
Member Rating: 3.8


Message 251 of 268 (671482)
08-26-2012 6:14 AM
Reply to: Message 246 by David Carroll
08-25-2012 1:10 AM


Re: c & t
Thus, a change in c would imply a change in the speed of propagation of waves in the electro-magnetic field and the weak field and the strong field. This would, in my opinion (none of this has been proven empirically.....it is indeed speculation on my part, but based strongly on a general knowledge of how physics works), result in a change of rate at which the strong field, weak field, and electro-magnetic field interact with each other.

How strong a general knowledge? If you couldn't prove it empirically, which you can't, then if you knew enough physics then you could prove it theoretically, which you haven't.

So if you can't do that then it's the sort of idea that might come to one in one's bath.


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Percy
Member
Posts: 15630
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.2


Message 252 of 268 (671485)
08-26-2012 9:49 AM
Reply to: Message 248 by David Carroll
08-25-2012 2:05 AM


Re: c & t
Hi David,

The speed of light, denoted by c, is a fundamental property of our universe. It just so happens that photons in a vacuum travel at c, so we can measure c by measuring the speed of photons in a vacuum. Photons traveling in a vacuum at speeds other than c would mean our universe is a much different place than the one we live in, and since our universe is precisely the one we do live in we can be sure there are no photons out there bouncing around at supraluminal velocities.

If it would satisfy your experimental curiosity you could devise an experiment to measure the speed of light of photons arriving from a distant galaxy.

--Percy


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NoNukes
Member
Posts: 9547
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


(1)
Message 253 of 268 (671504)
08-26-2012 6:25 PM
Reply to: Message 251 by Dr Adequate
08-26-2012 6:14 AM


Re: c & t
So if you can't do that then it's the sort of idea that might come to one in one's bath.

Not that there is anything wrong with a Eureka moment in the bath.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

“Choose silence of all virtues, for by it you hear other men's imperfections, and conceal your own.” George Bernard Shaw


This message is a reply to:
 Message 251 by Dr Adequate, posted 08-26-2012 6:14 AM Dr Adequate has not yet responded

    
NoNukes
Member
Posts: 9547
From: Central NC USA
Joined: 08-13-2010
Member Rating: 3.1


Message 254 of 268 (671517)
08-26-2012 7:47 PM
Reply to: Message 252 by Percy
08-26-2012 9:49 AM


Re: c & t
The speed of light, denoted by c, is a fundamental property of our universe. It just so happens that photons in a vacuum travel at c

Every time I read these phrases, the content nags at me, and finally I had to post. "c" is the speed of light in empty space. If there is a coincidence, it is that "outer space" behaves like empty space. It is not a coincidence that photos travel at the speed of light.

I agree with your point about the speed of light in empty space being a fundamental property of the universe.


Under a government which imprisons any unjustly, the true place for a just man is also in prison. Thoreau: Civil Disobedience (1846)

The apathy of the people is enough to make every statue leap from its pedestal and hasten the resurrection of the dead. William Lloyd Garrison.

“Choose silence of all virtues, for by it you hear other men's imperfections, and conceal your own.” George Bernard Shaw


This message is a reply to:
 Message 252 by Percy, posted 08-26-2012 9:49 AM Percy has responded

Replies to this message:
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Percy
Member
Posts: 15630
From: New Hampshire
Joined: 12-23-2000
Member Rating: 4.2


Message 255 of 268 (671527)
08-26-2012 10:28 PM
Reply to: Message 254 by NoNukes
08-26-2012 7:47 PM


Re: c & t
You might be reading too much into the phrase "It just so happens," but interestingly, the speed of photons is c in any medium. When traveling through a material like air or glass light travels between molecules at c - the slower effective propagation rate is due to the time taken for absorption followed by emission of a new photon.

--Percy


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