How Gravity Works

[ChildInAZoo]

Noted. And when I do and quote it back at you along with the patent evidence, you won't listen, and instead you'll accuse me of thumping the tub for Einstein. There's nobody home, lpetrich.

You are seriously confused about the nature of scientific evidence. Saying that something must be the case in physics because Einstein said that it must be so is not scientific evidence. So you are incorrect to try to appeal to Einstein as a source of evidence. However, as lpetrich notes, you are also wrong about Einstein's position on physics. This is a matter of textual analysis and it does depend almost entirely on what Einstein wrote. Reading the work lpetrich suggests would help you have a better textual analysis of what Einstein wrote. If you were to actually learn how to use the science that Einstein developed, that would also help you do the textual analysis, whether or not that science was correct.

[lpetrich]

That's a global effect, a side effect of space-time curvature. The local speed of light in a vacuum remains constant.

Read the OP, lpetrich. The curvilinear motion that we call curved spacetime is the result, not the cause.

That's not how General Relativity works -- the space-time curvature induces the trajectories' curvature, and no amount of word salad can change that about GR.

Seems like Martin Gardner's criterion 4: inverting mainstream theories.

[Farsight]

I haven't inverted it lpetrich. In 1916 Einstein said die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert which translates into the speed of light varies with the locality. So in Relativity: the special and general theory he's saying a curvature of rays of light can only take place when the the speed of light varies with the locality. And in his Leyden address of 1920 he said this:

According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty.

That's Einstein telling you about inhomogeneous space and the variable speed of light. Not curved spacetime. So it isn't me who's inverted it lpetrich. It's you.

[ChildInAZoo]

Farsight, if you haven't inverted things, please show us where in the equations of Einstein's general relativity your interpretation is found.

[Ulven]

Farsight,

I haven't inverted it lpetrich. In 1916 Einstein said die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert which translates into the speed of light varies with the locality. So in Relativity: the special and general theory he's saying a curvature of rays of light can only take place when the the speed of light varies with the locality. And in his Leyden address of 1920 he said this:

Einstein wrote:According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty.

That's Einstein telling you about inhomogeneous space and the variable speed of light. Not curved spacetime. So it isn't me who's inverted it lpetrich. It's you.

I took the liberty of checking the German Wikipedia for the correct translation of the term "Geschwindigkeit", and, lo and behold, "Geschwindigkeit" is the same as velocity. Although in everyday terminology it can be taken as either speed or velocity, when distinguishing between velocity and speed, the terms "Tempo" or "Schnelligkeit" are used for speed, while "Geschwindigkeit" is reserved for the vectorial quantity velocity. How does this jive with your interpretation of Einstein's statements?

In your second post on this thread you make the claim that:

"People swear that Einstein told us about curved spacetime, but when you read The Foundation of the General Theory of Relativity it's just not there.Yes, he talks about geometry and curvature and space-time, but he's giving the equations of motion, through space. He doesn't talk about "motion through spacetime" like people do these days. "

This sounded fishy to me, so I checked equation 46 in section 13 and sure enough, there was Einstein telling us about the equations of motion in four-dimensional curved space-time.

Didn't you read that part? I mean, if you're going to use Einstein's statements as the basis for your argument, you should anticipate that somebody is going to check things like that.

[Farsight]

You are seriously confused about the nature of scientific evidence. Saying that something must be the case in physics because Einstein said that it must be so is not scientific evidence..

The GPS clock adjustment and the Shapiro delay are the scientific evidence. The Einstein quotes are the references. Duh!

[Twiglet]

Farsight,

I haven't inverted it lpetrich. In 1916 Einstein said die Ausbreitungsgeschwindigkeit des Lichtes mit dem Orte variiert which translates into the speed of light varies with the locality. So in Relativity: the special and general theory he's saying a curvature of rays of light can only take place when the the speed of light varies with the locality. And in his Leyden address of 1920 he said this:

Einstein wrote:According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that “empty space” in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty.

That's Einstein telling you about inhomogeneous space and the variable speed of light. Not curved spacetime. So it isn't me who's inverted it lpetrich. It's you.

I took the liberty of checking the German Wikipedia for the correct translation of the term "Geschwindigkeit", and, lo and behold, "Geschwindigkeit" is the same as velocity. Although in everyday terminology it can be taken as either speed or velocity, when distinguishing between velocity and speed, the terms "Tempo" or "Schnelligkeit" are used for speed, while "Geschwindigkeit" is reserved for the vectorial quantity velocity. How does this jive with your interpretation of Einstein's statements?

In your second post on this thread you make the claim that:

"People swear that Einstein told us about curved spacetime, but when you read The Foundation of the General Theory of Relativity it's just not there.Yes, he talks about geometry and curvature and space-time, but he's giving the equations of motion, through space. He doesn't talk about "motion through spacetime" like people do these days. "

This sounded fishy to me, so I checked equation 46 in section 13 and sure enough, there was Einstein telling us about the equations of motion in four-dimensional curved space-time.

Didn't you read that part? I mean, if you're going to use Einstein's statements as the basis for your argument, you should anticipate that somebody is going to check things like that.

+1

[ChildInAZoo]

You are seriously confused about the nature of scientific evidence. Saying that something must be the case in physics because Einstein said that it must be so is not scientific evidence..

The GPS clock adjustment and the Shapiro delay are the scientific evidence. The Einstein quotes are the references. Duh!

In what work of Einstein does he discuss the GPS clock adjustment and the Shapiro delay? Regardless, if you want to use GPS and Shapiro as evidence that there is a change in the speed of light, please show us the calculations that match up with these particular sets of observations. You need to address the actual content and logic of the science, notmerely mention it.

[Farsight]

Farsight, I took the liberty of checking the German Wikipedia for the correct translation of the term "Geschwindigkeit", and, lo and behold, "Geschwindigkeit" is the same as velocity. Although in everyday terminology it can be taken as either speed or velocity, when distinguishing between velocity and speed, the terms "Tempo" or "Schnelligkeit" are used for speed, while "Geschwindigkeit" is reserved for the vectorial quantity velocity. How does this jive with your interpretation of Einstein's statements?

Relativity: The Special and General Theory was a popular science book. This is the everyday usage. Check the translation with native-German speakers and they'll confirm what I say. Take care with online translations. For example somebody has changed the google translate to read "type" instead of "locality".

In your second post on this thread you make the claim that:

"People swear that Einstein told us about curved spacetime, but when you read The Foundation of the General Theory of Relativity it's just not there.Yes, he talks about geometry and curvature and space-time, but he's giving the equations of motion, through space. He doesn't talk about "motion through spacetime" like people do these days. "

This sounded fishy to me, so I checked equation 46 in section 13 and sure enough, there was Einstein telling us about the equations of motion in four-dimensional curved space-time. Didn't you read that part? I mean, if you're going to use Einstein's statements as the basis for your argument, you should anticipate that somebody is going to check things like that.

Yes, I've read it all, umpteen times. Look at the top of page 179. It's perfectly clear. The motion through space is plotted as four-dimensional line in the mathematical space we call spacetime. When "the spacetime is curved" the motion through space isn't uniform, but the motion is still through space, not through spacetime. Have a google on "Nasty Little Truth About Spacetime Physics".

[Farsight]

In what work of Einstein does he discuss the GPS clock adjustment and the Shapiro delay? Regardless, if you want to use GPS and Shapiro as evidence that there is a change in the speed of light, please show us the calculations that match up with these particular sets of observations.

Oh get lost. The scientific evidence is what it is. The GPS clocks are atomic clocks, which use a hyperfine transition and microwaves, electromagnetic phenomena. And radar signals passing near a massive object take slightly longer to travel to a target and longer to return than it would if the mass of the object were not present. The scientific evidence isn't what Einstein said, and it isn't calculations. Stop ducking and diving.

[ChildInAZoo]

In what work of Einstein does he discuss the GPS clock adjustment and the Shapiro delay? Regardless, if you want to use GPS and Shapiro as evidence that there is a change in the speed of light, please show us the calculations that match up with these particular sets of observations.

Oh get lost. The scientific evidence is what it is.

You are absolutely correct that the evidence is what it is. And no amount of telling people to "get lost" will change the fact that you have yet to explain the relationship between the variable speed of light and the actual measurements of any experiment. Show us the way that your theory matches up with the results. That is the only way that any scientist can rely on evidence from those experiments. Or does your science work through Papal fiat?

The scientific evidence isn't what Einstein said, and it isn't calculations. Stop ducking and diving.

The only one ducking and diving here is you. In the case of the specific experiments that you cite, calculation is required. You are talking about the "variable" speed of light. How does it vary? How does this allow us to get specific results from experiments? Are you just saying by Papal fiat that light varies in speed by just the right amount to get the results of any measurement, no matter what the experiment is?

[lpetrich]

You are seriously confused about the nature of scientific evidence. Saying that something must be the case in physics because Einstein said that it must be so is not scientific evidence..

The GPS clock adjustment and the Shapiro delay are the scientific evidence. The Einstein quotes are the references. Duh!

Those are global effects, not local effects, so they don't count. Furthermore, they agree very well with GR's predictions, and GR treats space and time as coequal, just as SR does.

[Farsight]

Those are global effects, not local effects, so they don't count...

Oh, they count all right. But there you go, dismissing the scientific evidence that's right in front of your nose. You'll do the same for parallel-mirror light clocks. Oh look, the one down at the surface of the planet has a lower reading. Ah yes, that's because of the time dilation! Ooh, let's talk about time machines! Quack quack quack!

[Farsight]

The only one ducking and diving here is you. In the case of the specific experiments that you cite, calculation is required. You are talking about the "variable" speed of light. How does it vary? How does this allow us to get specific results from experiments? Are you just saying by Papal fiat that light varies in speed by just the right amount to get the results of any measurement, no matter what the experiment is?

No, I'm just giving the scientific evidence and the references to Einstein and the simple logic that you can't counter. Look here it all is in the Op. Try reading and try countering it before you bluster on about papal fiat and confuse scientific evidence with references and calculations.

[ChildInAZoo]

[No, I'm just giving the scientific evidence and the references to Einstein and the simple logic that you can't counter. Look here it all is in the Op. Try reading and try countering it before you bluster on about papal fiat and confuse scientific evidence with references and calculations.

The reading is done. Now we are asking questions about what we read. One questions is whether or not your theory can use evidence like every other theory is expected to. The details of the GPS system and the details of Shapiro time delay are mathematical details of measurement. So let's see how what you wrote in the OP leads to matching the measurements. If you don't do this, you have no evidence.