🚀 go-pugleaf

On 9 fév, 23:46, rbwinn <rbwi...@juno.com> wrote:
> On Feb 9, 8:42�pm, Randy Poe <poespam-t...@yahoo.com> wrote:
>
>
>
> > On Feb 9, 7:53 pm, rbwinn <rbwi...@juno.com> wrote:
>
> > > OK, so you do not believe Kepler had a number.
>
> > I didn't say whether I believed Kepler had a number of not.
> > I asked you what number you were referring to.
>
> > > Kepler thought that he
> > > did. �It was R^3/T^2 = 3.353, more or less.
>
> > OK, that's a number. What about it?
>
> > > Newton used Kepler's number in his equation for the centripetal force
> > > on a planet.
>
> > No, Newton didn't "use Kepler's number". Newton
> > proved why R and T have this relation from more fundamental
> > considerations.
>
> > > Now I don't know what you are saying about welding.
>
> > I'm asking you what theory you want to talk about.
>
> > (1) Newton's theory, which would be the theory that, you know,
> > was Newton's. I will only insist on sticking to Newton physics
> > if you say that we are having a "pure Newtonian" discussion.
> > That would be what is implied by the words "Newtonian"
> > and "pure".
>
> > (2) GR, where time is affected by gravitational potential
> > and orbits are geodesics, or
>
> > (3) Some theory where you have welded GR results with
> > Newtonian equations, which is neither GR nor Newton but
> > a hybrid monster, and possibly not drivable.
>
> > I'm happy to talk about one, but you have to pick. Don't
> > say you're talking about (1) and then immediately switch
> > to (3).
>
> > You have some question about the GR effect of time
> > and gravitational fields. So we're in either (2) or
> > (3). Which is it, and what's your question?
>
> > � � � � - Randy
>
> I don't really have any questions any more.  I had a question about 20
> years ago which I posted in this newsgroup which was about the two
> little equations Einstein extracted from the Lorentz equations, x=ct,
> x'=ct'.   After years and years of nonsense, I finally figured out the
> answer to my question.  Einstein's two little equations were wrong.
> The Lorentz equations were not the correct equations for what Einstein
> said he was doing.
>      What I was discussing with you was the difference that according
> to scientists exists in Newton's equations if you use time from a
> clock in a satellite as compared with time from a clock on earth.
> Newton knew of no such time difference, so he never considered it.
> According to you, since Newton never considered it, it does not apply
> to his equations, and it would be "impure" in some way to compare this
> difference.
>        I say that if Newton's equations are applied using clock times
> from two different frames of reference, and two different
> gravitational constants are found, then one or the other or something
> in between must be the actual constant, since two different answers
> are not constant.
>    As for whether or not Newton used Kepler's ratio, I was basing what
> I said on what is said in a physics book, "Newton explained many years
> later that he was led to the correct force law by working backwards
> from Kepler's third law."
> So the fact of the matter is that either Newton did use Kepler's ratio
> R^3/T^2 or else the writers of that physics book lied about it.

Your quote is correct. Georges Gamow even explained how Newton
mathematically proceeded in his small book "Gravity", Science
Study Series, Doubleday, 1962, chapters 2, 3 and 4.

André Michaud

> It
> does not matter to me.  Kepler's ratio definitely fits into Newton's
> equation, whether the writers of that physics book lied about Newton
> using it or not.  Scientists lie all the time.  Possibly the writers
> of that book did lie as you are claiming, or maybe they just came to a
> wrong conclusion because it seemed logical to them.  Perhaps we will
> never know.  Why was it so important to you that Newton got his
> equation from somewhere else than Kepler's third law?
> Robert B. Winn