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Said LeGrande to Zero Sum:
You have come to this discussion a little late and I don't want to get bogged down in Galilean inertial frames.

Chimes in MrJesse:
It needn't be complicated. It ought to be far easier then waves of nothing! And besides, I think Zero Sum has a perfect understanding of the issue here. There's no way he joined the discussion too late! If it had been earlier would it have made a difference? I was there the whole time, and it didn't help me any :=)

The initial statement that I made was that an objects apparent position is not identical to its actual position at any given instant in time, primarily due to the speed of light. In other words when we see the Sun we see where it was apx 8 and a half minutes ago.

Your initial comment was this(Next to last paragraph):

Let me give you something else to think about : ) When you create a field it propagates at the speed of light to infinity. Once the field has been stabilized how fast are the changes in the field? In other words when you look at the Sun, you are seeing it about 7 minutes behind where it actually is, but if you had a sensitive gravity sensor where would it point? At the sun you see or 7 minutes ahead of the sun you see? The answer will help you understand what a field is, it is not a simple concept.(Emph. Mine.)

So you are quite clearly talking about the time of flight for the light from the sun to the earth, even though your question is a little ambigiuos since it's comparing time and angle.

Then, later you say (Fourth paragraph):

The suns actual position and gravitational position do line up. The apparent position doesn't though, it is off by 2.1 degrees like you indicated.

Your initial comments clearly indicate that you are talking about an observer on earth, at a single point in time who looks up and sees that the sun appears to be 2.1 degrees behind where it actually is at that same time. And furthermore, I have clearly stated the whole time that this is what I believed you to be claiming, and since you never said that it's not what you're claiming, that is what you've been claiming.

So in answer to your question:

"In other words when we see the Sun we see where it was apx 8 and a half minutes ago.

Do you agree or disagree with that statement?

The question is absurd, but let me explain. Let's say you're married, and let's say you sometimes go grocery shopping with your wife. Further let's say one day you're at a party, and you introduce your wife to your friends as a lady you see at the grocery store once in a while. What's her reaction going to be? What's the truth?

You see, when someone asks about your relationship to another person, they expect you to tell them the closest relation ship. So technically it is true that she is a lady you see at Safeway once in a while, but it's completely misleading because she is actually much more then that to you.

Since the sun is not moving (at least nowheres near your claimed 2.1 degrees/8.3 minutes), the truth is that the sun appears where it is (plus or minus 21 arcseconds due to other causes.) Now since it is in the same place now that it was 8.3 minutes ago - yes, technically, we are looking at where it was 8.3 minutes ago - but that's not an honest way to describe it because 8.3 minutes ago it was where it still is, so it's more direct and honest to just say "it is where it appears to be(+/- 21ArcSeconds.)

So your whole premis, that if we had a sensitive gravity meter we could detect that the sun was 2.1 degrees ahead of wher it appears, is wrong, because the sun is not orbiting the earth, and as such, the sun is where (+/-21AS) where it appears.

So, yes, the sun does appear to be where it was 8.3 minutes ago. It also appears to be where it is now, because where it is now is where it was 8.3 minutes ago, because it hasn't moved in 8.3 minutes!

MrJesse is quit adamant that the actual position is the same as the apparent position, except for a little parallax that I taught him about.

It is true that I am quite adamant that the actual position of the sun is the same (within about 21 arcseconds) as the apparent position for an observer on earth at any point in time.

The 21 arcseconds has nothing to do with parallax, but rather the observer's transverse velocity through space at 67K miles per hour, as the earth complete's its yearly journey around the sun. It has nothing whatsoever to do with the distance to the sun, and little to do with the rotational rate of the earth. (The transverse (sideways) velocity on the surface of the equator due to the earth's rotation is only about a thousand miles an hour, which is drawfed by the 67K mph due to the earth orbiting the sun.)

But I will be forever greatful for LeGrande putting me onto the words "Stellar Aberration" and "Light-time correction." I hope someday he understands them. ;-)

Now, most noble LeGrande, I've answered several of your tough questions to me.. Any chance you might be so kind as to go answer at least one of my color coded questions?

(Hey, TXnMA: Perchance you could answer a few more too? It'd make me sad to know that there are two people out there that refuse to apply their view to a set of simple questions!)

Thanks a million!

-Jesse

You have come to this discussion a little late and I don't want to get bogged down in Galilean inertial frames.

The discussion of inertial frames applies to Lorentz transformations as well, which, like Galilean transformations, are linear. The transformations for rotational frames are not, which is why a rotating frame is not inertial.

The initial statement that I made was that an objects apparent position is not identical to its actual position at any given instant in time, primarily due to the speed of light. In other words when we see the Sun we see where it was apx 8 and a half minutes ago.

Do you agree or disagree with that statement?

If I answer this then will you do me the courtesy of answering the quesions that I posed in my previous post? If you demand that I answer your questions but you refuse to answer mine then I don't see any use in continuing this discussion, nor will I respond to you again unless and until you show the courtesy to reciprocate. If you choose not to then my post stands, and I have no reason not to be content with that.

Now, I answer that there are two statements there.

1) "The initial statement that I made was that an objects apparent position is not identical to its actual position at any given instant in time, primarily due to the speed of light."

I agree if you insert the word "necessarily" before the word "identical". However, there are certainly cases where an object's apparent position can coincide with its actual position, the case of a stationary object WRT an observer in an inertial frame being the trivial example. Here is another example:

2) "In other words when we see the Sun we see where it was apx 8 and a half minutes ago."

This is true, of course. But the crux of the matter here is: Where was the sun 8.5 minutes ago? Was it where we see it now or was it where we saw it 8.5 minutes ago, 2 degrees behind where we see it now? The former is the correct answer because the apparent motion is due not to the Sun revolving around us, but due to our rotation, and as I've tried to make clear already, these are not relative. If you would argue that they are, then kindly address the questions from my previous post.

MrJesse is quit adamant that the actual position is the same as the apparent position, except for a little parallax that I taught him about.

And he is correct (although we should take into accout refraction due to the atmosphere as well, but that's a different story). In your Earth/Pluto thought experiment you will not get 102 degrees difference from parallax, not even close. The correction for parallax will be miniscule. Nor will you get even close to 2 degrees due to parallax in 8.5 minutes considering the position of the Sun as seen from the surface of the Earth.

But since we are discussing rotating frames (which for some reason you seem to think are inertial) let's keep our thought experiments focused on that. Or better yet, do a real experiment and see for yourself the difference between spinning and orbiting. And keep those questions from my previous post in mind when you do. :)