Measuring sun's true direction

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Hence the intensity of the field at the surface would ultimately become infinite with increasing radius R of the sphere, which is impossible.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

However, if Le Sage-like gravitons exist, they must have some finite size, however small that might be. So sooner or later, any graviton will run into another graviton and get scattered, its original path diverted.

In the Meta Model, the length of this "mean free path" of a graviton before it collides with another graviton is about 1-2 kiloparsecs (3000-6000 lightyears). Because no body can shadow another over a range much larger than that because all the gravitons would be scattered by then, gravitational force transitions from an inverse square force into a non-force over very long ranges. As a bonus, this change in character of gravity nicely solves the missing "dark matter" problem in cosmology without need of dark matter.

So the answer to your objection is simple. If (and only if) gravity is a pushing particle, gravitational force is protected from becoming infinite in an infinite universe by the finite range of its force. And the observed behavior of gravitation at long range is consistent with this type of behavior predicted by pushing gravity models.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Remember, I'm a total idiot in these matters<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

No, it is a good question. Sometimes, critics of a model don't like its unfamiliarity or its implications and don't take the time to examine it. They may simply assume that naive errors have been made in model development. But the 24 authors in <i>Pushing Gravity</i> were summarizing the related work and objections of every bright physicist for the last 250 years, and did not gloss over any objections. So by merely asking the question instead of assuming the answer, you distanced yourself from the real "total idiots". <img src=icon_smile_clown.gif border=0 align=middle> -|Tom|-

By times it seems there is a lot of anger between people on this message board (in recent times especially) <img src=icon_smile_sad.gif border=0 align=middle> Is there perhaps somewhere some list of preferred conduct or guidelines on how to 'act' when posting messages on this message board? As far as I'm concerned behaviour like this does not belong on a 'publicly' accessible message board, not to mention a place where civilized people communicate.

I'm not offended [Mark] but others might take on the negative sentiment. Perhaps this is something the moderator must act upon when needed.

The reason I attempted to do the calculation was to put it into 'units' that is more familiar to the ‘more’ average person and astronomer like light years and seconds. That way the ‘short’ distance between Sun-Earth could be put into perspective. Indeed, when I started with the calculation I did not think that the distance travelled in one second by an average graviton (all base on assumptions) would be that great.

All in all, it showed us what kind of speeds we are talking about and that a speed like ‘light speed’ is relatively small.

The reason I used 365.26 in my last calculation was that I was convince that I have seen the .26 in some astronomy handbooks instead of .25. I believe it depends on the definition of ‘day’ because there is a difference between sidereal year (365.2564) and normal years. But who’s counting days at that speed anyway! <img src=icon_smile.gif border=0 align=middle>

Rudolf

Because no body can shadow another over a range much larger than that because all the gravitons would be scattered by then, gravitational force transitions from an inverse square force into a non-force over very long ranges. As a bonus, this change in character of gravity nicely solves the missing "dark matter" problem in cosmology without need of dark matter.

Van Flandern

Not that easy as you may think. You're assuming no other bodies in between. There are bodies all over the place and one body acts like a force transmission for the other. What you say would be true for a universe with a very low density, maybe a few galaxies around. If the universe is infinite as you say, then before scattering takes place another body comes along to act as a local "concentration camp" for gravitons and original force is transmitted all the way down to the other end of the universe. Your model seems to be in disagreement with current observations regarding the number of galaxies and matter in it. But again, I am a total idiot.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>You're assuming no other bodies in between.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

I thought about whether to give you the complete answer, or a simple one. Because you keep insisting you are a total idiot, I simplified. But you came right back with a question about the part I left out. If you want complete answers, you need to provide some guidance about what level of discussion you are prepared for.

Take galaxies for example. 1-2 kpc just covers their central haloes. That is where the matter distribution is spherical. Once you get beyond the 1-2 kpc range of gravitational force, though, then only the "join-on" effect you describe very well is operative. But that can be stable only in a plane, which is apparently why galaxies are always flattened to a plane.

As this applies to the Sun, it means the Sun feels no force from the Galactic center. But it feels more force from stars closer to the center but within 1-2 kpc of the Sun than from stars farther from the center because the latter are spread over more volume and hence have less space density. The vertical radius of the disk is also 1-2 kpc.

The net of the join-on forces is that stars like the Sun act as if the force were still coming from the center, but changed from inverse square to inverse linear. Inverse linear is just what is needed to eliminate the need for dark matter at all scales. And computer simulations show that only inverse square and inverse linear laws (out of all integer possibilities) give stable objects; and of the two, inverse linear more closely resembles the forms actually seen among galaxies, especially interacting ones.

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>Your model seems to be in disagreement with current observations regarding the number of galaxies and matter in it. But again, I am a total idiot.<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Isn't that getting a bit old? Just ask your questions and judge whether or not the ground has already been covered and if the answers are reasonable. Your shtick makes it sound like you are needling, which might not be your intention at all. -|Tom|-

Sorry to through off the 'other' discussion (but this was my topic to begin with <img src=icon_smile_wink.gif border=0 align=middle> )

When dealing with galactical distances the time delay between galaxy centre and the sun is appreciatable - in the region of almost a minute. However, as Tom pointed out at that distance there might not be any direct gravitational pull between sun and galaxy centre.

I wonder however if the accumulative effect of stars pulling the sun towards the galaxy centre might have a similar issue with propagational delays causing stars to drift outwards over the timespan of millions or bollions of years? Once again there are other causes that might be stronger to cause this effects.

Rudolf

[mechanic] might be a 'total idiot' but I'm still a layman. <img src=icon_smile.gif border=0 align=middle>

<BLOCKQUOTE id=quote><font size=2 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>I wonder however if the accumulative effect of stars pulling the sun towards the galaxy centre might have a similar issue with propagational delays causing stars to drift outwards over the timespan of millions or billions of years?<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>

Yes. One active possibility is that all stars spiral away from their galaxy's central halo region, which is one mechanism for producing spiral arms.

It also would help solve the great "wind-up" mystery about spiral arms in galaxies. It is a problem to explain how galaxies have spun 10-50 times since their birth, yet the spiral arms don't "wind up".

All the stars in the spiral arms have roughly the same measured orbital speeds. But the farther out stars have farther to travel to complete an orbit than the close-in stars. So how does the arm keep its shape instead of winding around the galaxy dozens of times? -|Tom|-