But if your understandings/interpretations are 'comic book version' because you don't take into account that 'rider' to Einstein's 2nd Postulate, then you are NOT REALLY DOING or UNDERSTANDING GR correctly, are you?
The Speed of Light is Not Constant
- Thread starter Farsight
- Start date
But if your understandings/interpretations are 'comic book version' because you don't take into account that 'rider' to Einstein's 2nd Postulate, then you are NOT REALLY DOING or UNDERSTANDING GR correctly, are you?
Again with the distraction troll tactics. It's online everywhere the two complete postulates are stated. Waste your own time, not everyone else's, troll.
What's with the sophistry avoiding the bleeding obvious, mate? If every PROCESS is affected/slowed, then ANY CLOCK processes rate is affected. That is the bottom line. No amount of 'spreading the obvious' farther afield to other abstract 'time' abstraction FROM those REAL processes is just plain wanting-it-your-way at all costs to the plain obvious FACT Farsight is pointing to according to GR effects as predicted on ANYTHING including clock processes and other phenomena in that GR situation.
How about arguing the FACTS according to the predicted LOCALLY REAL GR EFFECTS rather than just more abstract overlays about your 'time' that is mere REFLECTION of the PROCESSING RATES of REAL THINGS affected by GR conditions, not some abstract derivation of them called 'time'. Thanks.
Well gee, if it weren't for there being a word called "time", there wouldn't be anything for Farsight to argue about. That isn't our choice, it is his. None of the rest of us have any confusion about the definition of the words "clock" and "time" and the fact that they can be considered a tautology (time is what clocks measure).What's with the sophistry avoiding the bleeding obvious, mate? If every PROCESS is affected/slowed, then ANY CLOCK processes rate is affected. That is the bottom line. No amount of 'spreading the obvious' farther afield to other abstract 'time' abstraction FROM those REAL processes is just plain wanting-it-your-way at all costs to the plain obvious FACT Farsight is pointing to according to GR effects as predicted on ANYTHING including clock processes and other phenomena in that GR situation.
How about arguing the FACTS according to the predicted LOCALLY REAL GR EFFECTS rather than just more abstract overlays about your 'time' that is mere REFLECTION of the PROCESSING RATES of REAL THINGS affected by GR conditions, not some abstract derivation of them called 'time'. Thanks.
But hey, good to know you are onboard with Farsight's arguing over nothing. Empty crackpottery, as I like to call it. :thumbsup:
By the way: I'm sure you just missed post #500 because it was the last one on the page, right? You really intend to respond to the substance of it, right?
What silly rationalizations. No wonder the profession is in a mess. Einstein was right, the mathematicians confuse everting. They can't tell the difference between REAL things and ABSTRACTIONS. What a revelation! Not.
Mate, how could those two totally and fundamentally DIFFERENT things possibly be thought by ANYONE (except maybe by some poor mathematician who has lost the plot) to be a "tautology". Clock process is REAL, 'time' abstract convenient analytical tool is UNREAL except AS an abstract analytical tool.
With that totally bizarre logic/argument of yours above, you would call the REAL frequency/wavelength of a photon and and its 'colour' in our brains 'perceptions' representations a "tautology" too! They are two totally different things. Period.
What's next? Science FICTION version of TIME TRAVEL ALONG THE GRAPHING ABSTRACTION "TIME AXIS"? Careful of the 'paper cuts' when reversing along the 'time axis' too suddenly, mate!
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What actual value are you referring to when you say 'plug in'? Please be clear what you are referring to.
It sure is quite a mystery!
Clock:
1. a device other than a watch for indicating or measuring time
http://www.merriam-webster.com/dictionary/clock
That definition is just too confusing for my little mathematical brain to understand - could you explain it to me?
Um....that's the question I'm asking you?!: what is the value - the number (and its units) - for "c" that is plugged into that equation?
For example, if I were to ask you to compute the GR time dilation of a GPS satellite vs a ground-based clock, can you do that?
Is this your admission that you have no idea how to use that equation?
It sure is quite a mystery!
Clock:
1. a device other than a watch for indicating or measuring time
http://www.merriam-webster.com/dictionary/clock
That definition is just too confusing for my little mathematical brain to understand - could you explain it to me?
Are you using a COMMON language disctionary 'usage' as the definitive PHYSICS usage? How many times have the 'experts' here berated the 'cranks' for working from common usage instead of physics usage? My my, no wonder you're all at sea on that.
The 'indication' and 'measuring' is the actual count/tick REPRESENTATION on a clock FACE or a clock COUNTER, not a separate independent 'thing' called 'time'. The INTERPRETATION of that clock face/counter INFORMATION represents EVENTS, not 'time' as such. It is our use OF that information in our abstract comparative/analysis purposes/constructs that is 'time', not the actual real MOTIONS/EVENTS from which that abstraction was derived.
Even Einstein pointed that out when he explained that when we speak of a 'time', what we really mean is a connection we draw between TWO simultaneous EVENTS. Such as "When I see the hour hand on my watch point to 7 O'clock, I also see the train pull into the station".
You don't even know that, yet you pretend to Farsight that you 'know' What Einstein said about his own theory of Relativity? Pull the other one, it has bells on, mate!
Not so fast, matey. It's your 'plug-in, so tell me what TERM you are 'plugging in' FOR. Thanks.
I can't add anything to Undefined's post #487.
Yes. It really is that simple in this case. Need Einstein to say it? Here he is:Undefined said:
http://patrick.maher1.net/318/lectures/eins1.pdfEinstein said:
Be careful with that link - it is a to a university physics course on Relativity and if you let your guard down you may accidentally learn something.
Are we not speaking the same language here? Do you not understand what the words "term" and "plug in" mean?
A "term" is a symbol (a variable or constant) or number in an equation.
"Plugging in" is replacing the term with its appropriate numerical value.
Here's a primer on middle-school math if you are unfamiliar with how this stuff works: http://www.mathsisfun.com/algebra/definitions.html
So: What is the number that "c" represents in that equation? I prefer SI units here, so please use the SI number.
...um...do you need me to explain what "SI" means too..?
I'm honestly at a loss here: I'm not sure if you are messing with me or if you really have absolutely no understanding of math whatsoever. Since you've avoided math here at all costs (I've never seen you do any math at all), I suppose it really is possible that you really do have absolutely no understanding of math at all. But I think you are an adult - you claim to be writing a book, which I've never heard of from a schoolchild (and few schoolchildren would be interested in a discussion like this). You are older than 12, right? Do you really not know any math at all? How did you avoid it in school? Or have you just forgotten how to math? I'm honestly not asking to be condescending: it would explain a lot about where you are coming from with your opinions if you honstly have no understanding of math at all.
Like Farsight, you assume that your understanding of what was written is what was written. You have a history of half-reading/half-remembering things. So, where is it that Einstein says what you think he says?Again with the distraction troll tactics. It's online everywhere the two complete postulates are stated. Waste your own time, not everyone else's, troll.
Hi OnlyMe.
Mate, why the double standards. No-one is using anything different that the SAME light clock illustrative device which is used by MAINSTREAM physicists illustrating their theoretical MOVING LIGHT CLOCK 'explanations' in SR context.
Only now we are considering the REAL EFFECTS locally of GR (as predicted) on real light clock counterparts that are NOT in abstract reciprocal-equality-perspective 'moving/SR' contexts, but in REAL LOCAL GR STATES predicted by Einstein and REALLY OBSERVED, irrespective of the 'quantitative differences involved in any one two-clock separation case in different GR altitudes.
Why is it that what's good for the goose is NOW all of a sudden NOT good for the ganger, mate? How about you all drop these inane/irrelevant DISTRACTION 'objections' and just LOOK at the REALITY in front of you for a change. Sheesh! You lot are so far removed from reality 'by inculcation' that you can't even find your way back to reality even when it's right UNDER YOUR NOSE.b Get real. Stop with the inane excuses/rationalizations/distractions from the REAL THING and discuss the RE$AL THING and not just your 'preferred fanntasy version/analysis' of same. OK? Thanks.
In a rush again today, and might be very busy again over the next few days. So I will be reading-only for a while after I log out today, so apologies if I miss replying to anyone. Cheers!
First, I don't apply a double standard. I just don't reply to all posts I have some conceptual or factual disagreement with. In this thread as it relates to the issue at hand I have objected to the use of a purely hypothetical construct, as if it proves anything. Hence the issue with making a distinction between what is known to be true and what remains theoretical.
The light clock, as used and described in Farsight's gif, has been at the basis of a great deal of his argument and it appears yours, even though it represents no real clock and the way it is presented, in the gif and text, is not consistent with how it was introduced and used by Einstein, nor used in current mainstream explanations of SR or GR. There is a big difference between using a hypothetical as a descriptive tool within the context of theory and presenting a hypothetical as proof of some reality. The big issue is the claim that what remains hypothetical or theoretical, is proof of what is real!
The bottom line is that the NIST optical clocks are not light clocks. There are no real light clocks in the sense portrayed by Farsight's gif, and the NIST optical clocks do not provide any objective data associated with the claims made using the optical clock gif. They don't measure or depend (directly) on the speed of light.
BTW - Where the issue of double standard is concerned, though as I said I don't respond to every post, where I have some difference of opinion, interpretation or understanding, I have in another thread, also one of Farsight's, pointed out a similar difference of interpretation, with a post on the opposing perspective, of that related discussion. In that case the issue was one of conceptual interpretation rather than the misuse of hypothetical as proof of fact.
I don't believe that in either case, I have taken a stand on the basic issues of whether, the speed of light is universally constant or what the fundamental mechanism of gravitation is... Though I have stated that I believe GR is an accurate description of how we observe objects interacting (gravitationally), and I have stated that the speed of light has been proven to be locally constant, while the universal aspect of the SR postulate has yet to be raised above the level of postulate... I have also stated that I don't believe that spacetime curvature is what causes gravity and that it does not make a difference to me whether the speed of light is constant or variable, within the context of GR.
Though I do have unstated opinions on both issues, both for me remain theoretical and unproven, whether I accept them within the larger context of the involved theory or not.
That is a good thing, as his post was based on nothing of merit.
It just isn't true. It's used to explain SR time dilation, see Wikipedia. Everybody who is familiar with relativity is comfortable with it.
That's not the case. There is no time dilation or length contraction associated with the local measurement of the speed of light. The measurement doesn't rely on the motion of the emitter or receiver. The tick rate of a clock at rest in the local proper frame has a 1/1 tick ratio with the tick rate of a clock in the remote bookkeeper proper frame at boundary [at rest, far away, in flat spacetime]. We need two clocks in different frames to determine any deviation from a 1/1 tick ratio between the frames.
dTau/dt_bkkpr = (1-2M/r_far away)^1/2 = (1-0_infinitesimal)^1/2 = 1
For the tangent space [on the manifold] and boundary [to the manifold] the tick rate is always 1.
The key 'is' tangent to every point on the Riemann manifold the spacetime is Minkowski [flat]. The connection between tangent planes, associated with points on the manifold, determine how large the tangent space can be locally. Basically a huge Laboratory frame where we can ignore any infinitesimal gravitational effects due to infinitesimal deviation between tangent planes. Except for the GPS where the infinitesimal deviation in tick rate effects the accuracy of the operating system. To clarify: tangent to every point on the manifold the spacetime IS flat. When you solve the Minkowski metric for 0 the local speed of light is an invariant
dr/dt = 1 [light]
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Yep, that makes sense....
I did put those musings/thought experiments rather poorly, and wasn't exactly what I was inferring.
I'll see if I can get my train of thought more coherent and get back to you....
Thanks brucep.
Yes it has been used in explanations of SR hypotheticals, you have been presenting it as some sort of proof within the context of GR. That said...
You need to go back and read the whole of that article. If you do you should notice that there are two hypothetical parallel mirror light clocks in the section. The first is an at rest version and the second is moving along the x axis. This is how I remember the hypothetical being presented, though I will admit it has been a very long time since I cracked open a text book, that used a light box example. As shown, it is a SR example... Further down on the Wiki page they do use the example, as part of an explanation of how SR handles time dilation in accelerated frames, but it remains hypothetical. No one has constructed a similar light clock to test it.
What you have been doing is changing the hypothetical by comparing the location, of two hypothetical light clocks, in a gravity well, adding your own conclusions and calling it proof that light is variable!
Wiki, your reference did not use the light clock example under the section headed gravitational time dilation. (I did not check to see if Wiki used a light clock when addressing the speed of light!)
While you can imagine what gravity would do to a light clock, your imagination is not proof.
I have no issue with you using the hypothetical as a part of your explanation of your beliefs. I have been objecting to equating it to some kind of proof! . . . You have how many times begun with the NIST optical clock example and then switched to the hypothetical light clock to say, "SEE HOW LIGHT GOES FASTER!".
Light clocks are not real and while they can be useful to help convey how we think things work, they will never be evidence of how things work... Unless and/or until someone makes a functioning light clock and uses it in an experiment.
Even then since the mechanics involved would be exceptional.., personally I would wait for some Peer Review, of the breakthrough.
It's easy to think that the local speed of light is an invariant because time and length are relative [the actual natural phenomena is somewhat counterintuitive to humans]. I had a conversation with several folks who thought the experiment to directly detect gravitational waves was flawed because they didn't take into account time dilation and length contraction, associated with the path of light between the test mass, would cancel out 'something or rather' so that we wouldn't be able to detect a change in distance between the test mass indicating a gravitational wave passed through the experiment model. Same mistake but understandable if you haven't studied the physics. "studied" a dirty word for cranks.
Sorry about the convoluted [somewhat] sentence. LOL