General relativity equation question

[Johnny5]

In another thread, which is now closed, swansont said this:

 

Yes' date=' you can measure it, because of the orbital laws that are in place let you take orbital observations and deduce the behavior of whatever it is you are looking at. The problem is that it appears that either the equation is not completely correct, that there is some other force in play, that there is mass that we can't observe, or some combination of all this, because the observed motion of some things in the cosmos doesn't follow what we expect. There are pros and cons that go along with all of these. Astronomers are still looking into it. [/quote']

 

The moment I read you say, "the problem is that it appears that either the equation is not completely correct, that there is some other force in play..."

 

I stopped dead in my tracks.

 

 

Did you just admit that astronomers have observed something, which implies that the general theory of relativity is either in error, or incomplete, was it GR that you were talking about?

 

Thank you

[Ophiolite]

1..admit implies attempts at concealment until now. Did you really mean that?

2. For one observation that is at odds, we have the stellar orbital velocities that don't stack up unless there is mass we haven't otherwise detected.

[Johnny5]

1..admit implies attempts at concealment until now. Did you really mean that?

2. For one observation that is at odds' date=' we have the stellar orbital velocities that don't stack up unless there is mass we haven't otherwise detected.[/quote']

 

In all seriousness, I have been getting the impression that Astronomers have learned something, but aren't ready to say it.

 

But I didn't mean to imply they are concealing it from the world no, that's a bit harsh.

 

But certainly, they better than anyone will someday know something which isn't known to all, it's the nature of their business. They gain knowledge about the universe, and that knowledge can only come to them from the study of the stars. Ordinary folk cannot know what astronomers know about the stars, that is utterly impossible since ordinary folk don't have access to observatories.

 

I wouldn't be at all surprised if Astronomers recently learned something important.

 

Look at Copernicus, Kepler, Brahe, Galileo. They all were the first to "know" something special, because they watched the stars.

 

The stars let us know our place in the cosmos. We get a sense of how the earth is moving through the universe. I think next to subatomic physics, astronomy is the greatest branch of physics there is.

 

And I do think that the greatest mind in human history will have to know all that an astronomer of today knows, and a bit more. (well minus the wrong part of course )

[Martin]

what is being discussed. it sounds like galaxy rotation curves and dark matter, but I can't tell

[Johnny5]

what is being discussed. it sounds like galaxy rotation curves and dark matter, but I can't tell

 

Martin, swansont's quote came from the thread just below this one, entitled, "Decisive answer please"

 

The question was about the speed of gravitational force.

[swansont]

Did you just admit that astronomers have observed something' date=' which implies that the general theory of relativity is either in error, or incomplete, was it GR that you were talking about?

 

...

 

Martin, swansont's quote came from the thread just below this one, entitled, "Decisive answer please"

 

The question was about the speed of gravitational force.[/quote']

 

No, actually the question had changed to basically if Newton's gravitational law was correct. Since my answer explicitly included GMm/r², it should be obvious to the most casual observer that it was not GR I was discussing.

 

What I was implying was indeed that the rotational speed of galaxies was not correct based on the observed mass; also the anomalous acceleration of the pioneer probes. One possible conclusion is that the equation isn't correct. What I didn't get into (other than say pros and cons) was the slew of problems you get into trying to keep observed orbital mechanics of our solar system correct while adjusting the equation. One other solution is dark matter, or another force that is only present over very large scales, so we don't observe it locally because it's so small.

 

Dark matter is hardly a secret being hushed up. Astronomers are actively and openly looking for it. GR has passed all of the experimental tests we can do that it is far more likely that one or both of the other solutions are correct, rather than GR being wrong.

[Johnny5]

I think GR is wrong though.

 

I could have told you that Newton's gravitational law cannot be correct.

 

It's impossible that it is correct, becase as formulated, it's an action at a distance formula, and the speed of gravity isn't infinite, it is finite, and nonzero.

 

But then that is why we have field theory now isn't it? It is there that we encounter the concept of "retarded potentials." A poor choice of words but whatever.

[5614]

And you think SR is wrong too.......

[Johnny5]

And you think SR is wrong too.......

 

Well I have a reason for each thought.

 

I hesitate to say belief, because... well I have a reason for what I think.