The Speed of Light is Not Constant

Now you're spouting total nonsense. I've referred to curved spacetime on many occasions.

Not at all.... your reply....
You've got it utterly wrong. Spacetime isn't space, it's an abstract mathematical model which is utterly static. The speed of light is not constant therefore your plot, your metric, is curved.

Only for the physical speed of light to be constant, your local region has to be infinitesimal. A region of no extent. No region at all.

No! That's what you've done. Now go and read the OP, and understand it.

Garbage. It's very easy stuff. The speed of light varies with position. Einstein said it, and those NIST optical clocks prove it.
You're just an ignorant naysayer, and you can't even work out how to quote somebody. You're back on ignore you troll.

to rpenner when he posted.....
>>>>>
Farsight has made hay on the point that because space-time is curved, the coordinate speed of light is not constant
>>>>>>>>>>>>>>>>>>>>>>>>>>


You're just an ignorant naysayer, and you can't even work out how to quote somebody. You're back on ignore you troll.


Please Farsight, don't make me laugh. You're the one falsely and delusionally claiming to have a ToE.....
You're the one who is constantly misquoting Einstein, and forever calling on him to support your nonsensical claims.
Then going all emotional and sanctimoniously indignant and putting me on Ignore. :shrug:
You are probably now the third troll to put me on Ignore.... :)
I'm really mortified :( [tic mode on of course]
 
Farsight, according to what I was taught and learned of Einstein's theory, I have to agree with your Post #754.
What you fail to realize is that Farsight means something more with the rest of his theory than what he wrote in that post. Farsight believes that there is an absolute reference frame in which one could in principle make a decision about what the real speed of light is. His theory is predicated on this.
 
What you fail to realize is that Farsight means something more with the rest of his theory than what he wrote in that post. Farsight believes that there is an absolute reference frame in which one could in principle make a decision about what the real speed of light is. His theory is predicated on this.

PhysBang, that is precisely why I explicitly stated "...with your Post #754.", in my Post #760!

Farsight had stated that he was referring to General Relativity in his Post #752 :
No, he'd be turning in his grave at the way general relativity has been traduced.
He then went on to reference yourself, the OP and to "quote" the Baez website on Gravitational Time Dilation in General Relativity.

PhysBang, that is why I Posted what I did in my Post #760 - The "ABSTRACT" stated :
C. W. Chou* said:
ABSTRACT
Observers in relative motion or at different gravitational potentials measure disparate clock rates.
We can now also detect time dilation due to a change in height near Earth’s surface of less than 1 meter.
- the ^^above quoted^^ from : http://www.sciencemag.org/content/329/5999/1630.abstract

As you probably well know, Gravitational Time Dilation in GR is not reciprocal, as opposed to Time Dilation being reciprocal in SR.

There was no good reason for paddoboy to "argue" the "ceiling/floor" example in his Post's #753 ; #757 ; #758 ; #761 ; or #767.

He even went on to state, in his Post #774, in reference to the "ABSTRACT" that I Posted :
Except for the new precision with the measurements, it's SR, pure and simple.
PhysBang, again, the "ABSTRACT" primarily dealt with the subject :
C. W. Chou* said:
ABSTRACT
Observers in relative motion or at different gravitational potentials measure disparate clock rates.
We can now also detect time dilation due to a change in height near Earth’s surface of less than 1 meter.
- the ^^above quoted^^ from : http://www.sciencemag.org/content/329/5999/1630.abstract

Gravitational Time Dilation near the Earth's surface is relevant in General Relativity - not Special Relativity!

PhysBang, as I stated in My Post #760 - I only presented that as "assistance" for any Members or Readers that would aspire to further learned knowledge of the full aspects of understanding and interpretation of Einstein's theory.

Some Members or Readers may not realize that Precision Measurement is quite possibly the First Real Science of Humanity and is fundamental and extremely important to all Real Sciences!

Heck, PhysBang, some may not even know what Metrology is!
 
There was no good reason for paddoboy to "argue" the "ceiling/floor" example in his Post's #753 ; #757 ; #758 ; #761 ; or #767.

No that's totally false.
The postulate in SR that the speed of light is constant has been argued constantly by Farsight and misinterpreted by him. He has been corrected many times, by many including JamesR.


It is a basic postulate of the theory of relativity that the speed of light is the same in all inertial frames. This can be broken down into two parts:

The speed of light is independent of the motion of the observer.
The speed of light does not vary with time or place.

http://math.ucr.edu/home/baez/physic..._of_light.html
 
Observers in relative motion or at different gravitational potentials measure disparate clock rates. These predictions of relativity have previously been observed with atomic clocks at high velocities and with large changes in elevation. We observed time dilation from relative speeds of less than 10 meters per second by comparing two optical atomic clocks connected by a 75-meter length of optical fiber. We can now also detect time dilation due to a change in height near Earth’s surface of less than 1 meter. This technique may be extended to the field of geodesy, with applications in geophysics and hydrology as well as in space-based tests of fundamental physics.
http://www.sciencemag.org/content/329/5999/1630.abstract
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

The above Abstract just confirms to a higher degree the fact of time dilation and length contraction.
Nothing whatsoever about the speed of light not being constant.
 
Be careful what you read, since you will tend to take away what you are looking for (that admonishment is mostly for the Farsights of the world. You have some leanings in that direction, which is why I mention it here).

This resurrects the long debated question of the meaning of "coordinate speed of light" which is pointless, other than to shore up the crap Farsight has been selling forever. It has no practical use. Every observer is constrained by his/her reference frame, and hence there is nothing else within a person's own definition of reality which has any meaning other than these two rules: (1) the speed of light is constant in my frame, and every other frame I will ever enter; and (2) every other frame looks to me like the projection of the hyperbolic rotation of the two axes of measurement (time and distance). That's it. There is no more. There is no "coordinate speed"; it's not even real. It's an artifact of introducing a Lorentz rotation by creating a second reference frame, then pretending to not know the frame diverged, and thus pretending that it shouldn't appear warped to me, and yet (of course) it is. This is a needless exercise in frivolous nonsense. So walk lightly here and take the first exit lest you be drawn into that black hole of ignorance that has sucked the Farsights and Reality Checks of the world into its singular compression of nonsense and error.

If you need any help spotting Farsight's cardinal sins, I can point to a recent post echoed by (paddoboy?) in which Farsight tries to claim that the observer's measurement of light speed is contaminated by "a second timeframe" (relative to an initial frame). But of course, if that were true, then length would be warped in the opposite direction, such that the quotient (c) comes out the same. Farsight continually omits this fact, in the manner of a true hardcore troll.

Also beware that all attempts to attack the constancy of c are probably rooted in the fundamentalist attempts to discredit radioisotope dating . . . so they can keep selling tickets to their knucklehead theme park which depicts humans walking the Earth in the Jurassic. My impression of you is that you are somewhat religious, but that you are not stupid enough to buy into the Young Earth fraud on science. But if you follow the Farsights of he world to their end game, odds are you will land up at the Young Earth farm, which is a very lonely place to be . . . for people with even half their wits about them.

Wow, how observant you are. I'm still laughing. You sound like my dad with the 'knucklhead' one of my favs of all time. Write that book that I was talking about. I'll definitely read it. Dr. Toad read Farsights book. I'm still laughing. "knucklehead theme park". LOL.
 
This resurrects the long debated question of the meaning of "coordinate speed of light" which is pointless, other than to shore up the crap Farsight has been selling forever. It has no practical use. Every observer is constrained by his/her reference frame, and hence there is nothing else within a person's own definition of reality which has any meaning other than these two rules: (1) the speed of light is constant in my frame, and every other frame I will ever enter;


It makes one wonder, what drives these people to push such weird concepts?.
Is it simply what I have been shouting from the roof tops of late, with regards to delusions of grandeur and tall poppy syndrome?
It appears that way. It's also obviously such a waste of energy and bandwidth by these people!
I mean, really, what do they hope to achieve by pushing such crap?

In summing, the "coordinate speed of light" like you said, is neither here nor there. The local proper speed of light is always consistently "c", in any FoR, anywhere in the Universe.
 
Wow, how observant you are. I'm still laughing. You sound like my dad with the 'knucklhead' one of my favs of all time. Write that book that I was talking about. I'll definitely read it. Dr. Toad read Farsights book. I'm still laughing. "knucklehead theme park". LOL.

I had trouble.. I had to laugh some, and hold down my lunch some. About equally, I guess. Now I can just laugh. The pain is gone. :D
 
brucep said:
Wow, how observant you are. I'm still laughing. You sound like my dad with the 'knucklhead' one of my favs of all time. Write that book that I was talking about. I'll definitely read it. Dr. Toad read Farsights book. I'm still laughing. "knucklehead theme park". LOL.
I still can't get over it. I remember the first time I saw those robotic dinosaurs at Disneyworld. Evidently Ken Ham contracted the same or similar designers (imagine being in the position to do it one way and then the other) to go down in history as the singular numbskull who would erect a shrine to pseudoscience. Just think how people in the future will marvel that we didn't just put these people under civil commitment (which is a state of arrest and confinement, usu. to a mental hospital, for being a threat to society or themselves.) I believe he has Fred Flintstone somewhere in between all the begattin' between Adam and Jonah. If they have accepted even one snippet of history, they will note that the library at Ninevah was full of writings, so probably they put the Flinstones just a little before that era. With dinosaurs, of course. I suppose they were wiped out in the flood, since we all know dinosaurs can't swim. Oh, except crocs and alligators and of course turtles which at least go back to the Cretaceous. :rolleyes:

What Ken Ham really needs, and what Farsight should contract to build for him, is a museum that glorifies the ignorance of claiming that c is not constant in all frames, culminating in a laser-tag game that simulates the errors that can occur in radiometric dating. You aim at your buddy and pull the trigger, and it randomly measures him at the wrong distance as he stands in a given zone of the geologic eons, and a paint ball lands harmlessly on the ground, far short of the date tagged as a distance by the laser. A big scorecard all lit up in LEDs and laser strobes would show that the exponential function for decay is never realized, but rather it's a straight line with time axis that spans 6000 years. And with every discovery that it fell short, Lucifer would light up in a dark corner, groaning like the little girl in The Exorcist as Holy Water lashes at her skin like acid. Right at the end, when Young Earth is proven, there would be a thunderous roar of Handel's "Hallelujah Chorus" while a 30 foot hologram of a Charles Manson looking character rises out of the grave all robed in white and ascending into Heaven. A lot of CO[sub]2[/sub] would be released from the fog machines, but after that big gusher of a climax, and much speaking in tongues and rending of garments, the throng would be herded to the Climategate Museum, so the massive jets of CO[sub]2[/sub] would actually serve as a kind of segway. This is our playground, we can tear it up if we want to.

I suspect this is Farsight's end game. I can think of no other rationale that serves as much vanity as all that.


It makes one wonder, what drives these people to push such weird concepts?.
Is it simply what I have been shouting from the roof tops of late, with regards to delusions of grandeur and tall poppy syndrome?
It appears that way. It's also obviously such a waste of energy and bandwidth by these people!
I mean, really, what do they hope to achieve by pushing such crap?

In summing, the "coordinate speed of light" like you said, is neither here nor there. The local proper speed of light is always consistently "c", in any FoR, anywhere in the Universe.

I have always thought this was just an outgrowth of the War on Science launched by the Bushies (if you followed that saga from the Tropic of Capricorn). It was bizarre, almost an inquisition. And of course it took on a new life when they figured out how to manufacture "climate-gate". But it never occurred to me, until I came across this while recently reading a book about the War on Evolution, that the attempts to drive a wedge into their congregations insofar as the constancy of c is concerned, is strategically targeting an utterly bogus rationale for discrediting radiometric dating. They will want to show that the half-life law of nuclear decay is predicated on the constancy of c, but once they've discredited it among their sheeple, then now they have a new piece of pseudoscience to lay the groundwork for the Young Earth nonsense which seems to be growing in popularity . . .despite the fact that even hillbillies can now Google and run a few fact-checks of their own. But being hillbillies, they wouldn't want to do that. I suppose it opens the gates to Hell. I mean just look how many demons are already here are attacking poor Farsight. (The Martyr.)

It's not that it comes up too often in a sermon, but all the high school books now give a little mention of radiometric dating and the exponential law for decay. So it is a pesky little problem that needs more champions like Farsight. Once he shows that the exponential is an artifact of "wrong assumptions about the constancy of c" he'll be on the verge of a best-seller. I mean: why else would anyone go to so much trouble to deny something as basic as the mountains of evidence attesting to the constancy of c?

Of course, the Devil is in the details. :mufc: So let's not actually bother to talk about empirical evidence.
 
I had trouble.. I had to laugh some, and hold down my lunch some. About equally, I guess. Now I can just laugh. The pain is gone. :D

Oh hi there. Welcome to our resident "Trolling for Jesus" forum, where Lucifer comes back as Einstein to delay the Rapture. By creating the illusion of relativity of course. That's why it never existed until about 1905 or so. Plus that's why Einstein practically predicted it at age 16. He was of course experiencing prophecy of the black kind. And you'll notice these scientists rely a lot on mirrors but I'll skip the thousand or so posts we've had about the black magic that happens at the Brewster angle. :D
 
I have always thought this was just an outgrowth of the War on Science launched by the Bushies (if you followed that saga from the Tropic of Capricorn). It was bizarre, almost an inquisition. And of course it took on a new life when they figured out how to manufacture "climate-gate".
.


Yep, point taken.
If we believe all this "so called scientific bullshit" they are putting up on forums such as this, the next claims will be of the like, that Humans and dinosaurs co-existed, or that the Grand Canyon was formed by receding flood waters........
 
Since light provides sensory perception, it is a real entity. All effects on real entities need causes and mechanisms of action. Motion of light also has a cause and mechanism of motion. Linear speed of light is related to efficiency and nature of moving mechanism. Linear speed of light, in any region of space, appears constant because that is the highest linear speed at which corpuscles of light can be moved by moving mechanism, without causing its own breakdown.
Nainan
 
Farsight uses certain sorts of arguments that are very flawed, such as a complete lack of use of the mathematics of general relativity. Instead, Farsight uses arguments that may be described as scriptural exegesis, sacred-book interpretation. Arguments based on textual analysis of various quotes, though often ignoring contrary quotes and contrary context from the same authors and writings.

That's not what one finds in mainstream science.

Consider some classic works on general relativity:
Charles W. Misner, Kip S. Thorne, John Archibald Wheeler: Gravitation
Steven Weinberg: Gravitation and Cosmology

Or a recent review:
Clifford Will:
The Confrontation between General Relativity and Experiment

In those writings, I don't find any of the sort of arguments that Farsight uses. I don't find any quotes from Albert Einstein treated as revealed truth from an inspired prophet, I don't find "what Einstein told us" sorts of statements, I don't find anything about how terrible it is to deny Einstein, etc.
 
Which is why you are banned or marginalized on every website.
No, I'm banned from certain websites because some people like to tell everybody that they're the expert, and when somebody like me challenges their assertions with evidence and references, they permit trolls to make accusations and hurl abuse and derail the discussion and trash the thread. And if that doesn't work, they censor the discussion. Now, as I was saying, on the Baez website you can read about the speed of light varying in the room you're in:

Baez Website said:
"Given this situation, in the presence of more complicated frames and/or gravity, relativity generally relinquishes the whole concept of a distant object having a well-defined speed. As a result, it's often said in relativity that light always has speed c, because only when light is right next to an observer can he measure its speed—— which will then be c. When light is far away, its speed becomes ill-defined. But it's not a great idea to say that in this situation "light everywhere has speed c", because that phrase can give the impression that we can always make measurements of distant speeds, with those measurements yielding a value of c. But no, we generally can't make those measurements. And the stronger gravity is, the more ill-defined a continuum of observers becomes, and so the more ill-defined it becomes to have any good definition of speed. Still, we can say that light in the presence of gravity does have a position-dependent "pseudo speed". In that sense, we could say that the "ceiling" speed of light in the presence of gravity is higher than the "floor" speed of light.

Einstein talked about the speed of light changing in his new theory. In his 1920 book "Relativity: the special and general theory" he wrote: "... according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [...] cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity [Einstein means speed here] of propagation of light varies with position." This difference in speeds is precisely that referred to above by ceiling and floor observers."

The above is quite sufficient to counter both lpetrich's and your ad-hominem assertions. The speed of light varies with position. Einstein said it, the Baez website backs me up, and the evidence backs me up. See the OP for details.

Now do try to stay on topic.
 
Baez Website said:
Given this situation, in the presence of more complicated frames and/or gravity, relativity generally relinquishes the whole concept of a distant object having a well-defined speed. As a result, it's often said in relativity that light always has speed c, because only when light is right next to an observer can he measure its speed—— which will then be c. When light is far away, its speed becomes ill-defined. But it's not a great idea to say that in this situation "light everywhere has speed c", because that phrase can give the impression that we can always make measurements of distant speeds, with those measurements yielding a value of c. But no, we generally can't make those measurements. And the stronger gravity is, the more ill-defined a continuum of observers becomes, and so the more ill-defined it becomes to have any good definition of speed. Still, we can say that light in the presence of gravity does have a position-dependent "pseudo speed". In that sense, we could say that the "ceiling" speed of light in the presence of gravity is higher than the "floor" speed of light.

Einstein talked about the speed of light changing in his new theory. In his 1920 book "Relativity: the special and general theory" he wrote: "... according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [...] cannot claim any unlimited validity.* A curvature of rays of light can only take place when the velocity [Einstein means speed here] of propagation of light varies with position." This difference in speeds is precisely that referred to above by ceiling and floor observers.
Actually from Don Koks, "Is The Speed of Light Everywhere the Same?", The Original Usenet Physics FAQ (March 2014). Retrieved from http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_of_light.html 2014-08-14. Emphasis by Farsight. Emphasis by rpenner.


Farsight, you have provided a great example by quoting context and a mendacious, evil and loathsome example by ignoring it. The main thrust of Baez paragraph one is that only local relative speed comparisons are physically meaningful and the very definition of speed for a non-local object doesn't exist. "relativity generally relinquishes the whole concept of a distant object having a well-defined speed" The first paragraph then introduces a particular coordinate system with its ability to assign a well-defined but unphysical "pseudo speed" to any motion ('cause that's what coordinate systems do.) The bolded part of the first paragraph and the entire second paragraph are in terms of this "pseudo speed".
 
Farsight, you have provided a great example by quoting context and a mendacious, evil and loathsome example by ignoring it.
I'm not ignoring it, I'm quoting it. It's people like lpetrich and Physbang who are trying to get people to ignore it. So spare me your the mendacious, evil and loathsome. The "main thrust" of Baez paragraph is that the speed of light is NOT constant, and Einstein said it. Here's the paragraph again. Let me emphasise that main thrust:

Baez Website said:
"Given this situation, in the presence of more complicated frames and/or gravity, relativity generally relinquishes the whole concept of a distant object having a well-defined speed. As a result, it's often said in relativity that light always has speed c, because only when light is right next to an observer can he measure its speed—— which will then be c. When light is far away, its speed becomes ill-defined. But it's not a great idea to say that in this situation "light everywhere has speed c", because that phrase can give the impression that we can always make measurements of distant speeds, with those measurements yielding a value of c. But no, we generally can't make those measurements. And the stronger gravity is, the more ill-defined a continuum of observers becomes, and so the more ill-defined it becomes to have any good definition of speed. Still, we can say that light in the presence of gravity does have a position-dependent "pseudo speed". In that sense, we could say that the "ceiling" speed of light in the presence of gravity is higher than the "floor" speed of light.

Einstein talked about the speed of light changing in his new theory. In his 1920 book "Relativity: the special and general theory" he wrote: "... according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [...] cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity [Einstein means speed here] of propagation of light varies with position". This difference in speeds is precisely that referred to above by ceiling and floor observers."

Did you get that?

rpenner said:
...The bolded part of the first paragraph and the entire second paragraph are in terms of this "pseudo speed".
Was there some part of Einstein means speed here that you didn't understand? You do recall that PhysBang said this on another forum?

"In a sense, this was done in 1905, when Einstein developed special relativity. This constancy of the speed of light is a postulate of the theory, so it is "shown" through the effectiveness and practicality of the theory. The same is true for general relativity, developed in 1915, which holds that the speed of light is constant at any infinitesimal region of a coordinate system".

Note that the speed of light is constant in an infinitesimal region? That means it isn't constant in the room you're in. And a curvature of rays of light can only occur when the speed of light varies with position.

ETA:

You have emphasised relativity generally relinquishes the whole concept of a distant object having a well-defined speed. Understand this: we aren't talking about distant objects. We're talking about light in the room you're in. The light down near the floor goes slower than light up near the ceiling. If it didn't, NIST optical clocks at diffferent heights would stay synchronised, and your pencil wouldn't fall down.
 
Was there some part of Einstein means speed here that you didn't understand?
if einstein meant speed,
then why did he not use the word speed ?

when i was very young,
the talk was about women being very interested in soap operas.
coming to this site shows that this is incorrect.
 
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