🚀 go-pugleaf

On 7 feb, 14:55, Randy Poe <poespam-t...@yahoo.com> wrote:
> On Feb 7, 5:08 am, Albertito <albertito1...@gmail.com> wrote:
>
>
>
> > On 6 feb, 20:10, Randy Poe <poespam-t...@yahoo.com> wrote:
>
> > > On Feb 6, 2:57 pm, Albertito <albertito1...@gmail.com> wrote:
>
> > > > On 6 feb, 19:15, Randy Poe <poespam-t...@yahoo.com> wrote:
>
> > > > > On Feb 6, 2:00 pm, Albertito <albertito1...@gmail.com> wrote:
>
> > > > > > On 6 feb, 18:54, Randy Poe <poespam-t...@yahoo.com> wrote:
>
> > > > > > > On Feb 6, 12:39 pm, Albertito <albertito1...@gmail.com> wrote:
>
> > > > > > > > On 6 feb, 16:48, "Androcles" <Headmas...@Hogwarts.physics> wrote:
>
> > > > > > > > > <srp2...@gmail.com> wrote in message
>
> > > > > > > > >news:4695358e-db97-4485-94b4-06f417a451d4@i7g2000prf.googlegroups.com...
> > > > > > > > > On 6 fév, 02:34, Pentcho Valev <pva...@yahoo.com> wrote:
>
> > > > > > > > > >http://philipball.blogspot.com/2007/09/arthur-eddington-was-innocent-...
> > > > > > > > > > "With the technology then available, measuring the bending of
> > > > > > > > > > starlight was very challenging. And contrary to popular belief,
> > > > > > > > > > Newtonian physics did not predict that light would remain undeflected
> > > > > > > > > > - Einstein himself pointed out in 1911 that Newtonian gravity should
> > > > > > > > > > cause some deviation too. So the matter was not that of an all-or-
> > > > > > > > > > nothing shift in stars' positions, but hinged on the exact numbers."
>
> > > > > > > > > | Right.
>
> > > > > > > > > | Classical Newtonian mechanics predicts that light will bend with
> > > > > > > > > | twice the angle observed.
>
> > > > > > > > > How?
>
> > > > > > > > I'll tell you how. In order to see how newtonian gravity can
> > > > > > > > bend the trajectory of a photon, relativists fake it. They
> > > > > > > > magically tranform a photon with energy E into a particle
> > > > > > > > with mass m = E/2c^2, it is saying  half the mass in E = mc^2.
> > > > > > > > Then, relativists assume that particle passes by the massive
> > > > > > > > body from infinity travelling locally at c, and then they can
> > > > > > > > apply newtonian gravity to see how its trajectory is deflected
> > > > > > > > into a hyperbolic one. As a result there is a deflection angle
> > > > > > > > twice the observed one. A particle with mass m = E/c^2,
> > > > > > > > travelling locally at c from infinity, would be deflected in
> > > > > > > > the correct angle, under newtonian gravity.
>
> > > > > > > Why don't you do the Newtonian calculation before
> > > > > > > making this claim?
>
> > > > > > >           - Randy
>
> > > > > > The calculations have been already done by you relativists,http://www.theory.caltech.edu/people/patricia/obsertop.html
>
> > > > > Correct.
>
> > > > > > I'm only witness of that, and I see that if we double the mass
> > > > > > assumed for a photon we attain the correct answer.
>
> > > > > There are a great many assumptions in those
> > > > > equations which you are not aware of. You are trying
> > > > > to change the meaning of the symbols midstream.
>
> > > > > Here's what those orbital mechanics equations look like for
> > > > > planetary orbits:http://www.go.ednet.ns.ca/~larry/orbits/kepler.html
> > > > > Note that E is the sum of kinetic energy and potential
> > > > > energy. So what are you going to use for this E? Do
> > > > > you really want to use mc^2 and claim it's a Newtonian
> > > > > model?
>
> > > > > If you were doing Newtonian gravitation the way Newton
> > > > > did it to calculate the planetary orbits, you'd say
> > > > > the kinetic energy is (1/2)*mc^2, and the potential
> > > > > energy is -GMm/r. Then you'd find out that the mass m
> > > > > drops out, that is the parameter E/m = [c^2/2 - GM/r]
> > > > > does not depend on m.
>
> > > > > Let's start from the basics: What is the initial velocity,
> > > > > what is the acceleration, what is the result?
>
> > > > > Start out with a velocity c, mass m, distance R
> > > > > as it passes near mass M.
>
> > > > > The acceleration experienced by the mass m is
> > > > > GM/R^2. That is what you would apply to the velocity
> > > > > vector to get the change in velocity. It does not
> > > > > depend on m.
>
> > > > > Trajectories of small bodies through solar systems do
> > > > > not depend on mass.
>
> > > > It's simpler than that. Under newtonian gravity you never
> > > > can say that a photon is predicted to be deflected by twice
> > > > the correct angle, because under newtonian gravity photons
> > > > can't be addressed at all, only bodies with mass.
>
> > > Right. Unless you assume it has mass, as people did
> > > long before Einstein.
>
> > > Once you do, the path is independent of whatever
> > > mass you assume, just as any Newtonian path is.
>
> > > > You never
> > > > can fake a photon to behave as a particle with non-zero mass,
> > > > that's unphysical. If you do fake a photon to behave so, then
> > > > you attain a particle with mass travelling at c, which is impossible
> > > > under your assumptions (i.e nothing with mass can travel at c).
>
> > > What point are you trying to make? If the photon
> > > truly has no mass (as we believe) then the Newtonian
> > > model says it won't be deflected. Therefore gravitational
> > > lensing won't happen.
>
> > To claim that a theory predicts a photon will
> > not be deflected and to claim photons are outside
> > the domain of applicability of a theory are not
> > the same claim. Photons are outside the domain of
> > applicability of newtonian gravity.
>
> If massless. This is part of the standard model and would
> certainly upset a lot of modern physics if false, but
> it's still a caveat in all your statements, an assumption
> you're making.
>
> Thus the only theory which predicts deflection of photons
> in gravitational fields (to date) is GR. Are we agreeing
> on this?

Yes, GR tries to predict deflection of photons, and it works
nearly fine :-)

>
> If so, I can't figure out what anti-relativistic stance
> you're trying to make.

Are you seeing in my stance any anti-relativist fashion?.
I only say that newtonian gravity can't address bosons,
and that it is not correct claiming that newtonian gravity
predicts half the correct deflection angle. Even for W(+),
W(-) and Z bosons, which have mass, newtonian gravity
can't predict their respective deflection angles. Bosons
are outside the domain of applicability of newtonian gravity.

>
> > Therefore,
> > newtonian gravity gives no answers to questions
> > concerning photons.
>
> Unless you assume gravitational mass which is nonzero.
>
> Once you do, you get a deflection which is half the
> GR prediction.
>
No. It is clear that gravity behaves differently for fermions
that for bosons (included bosons with nonzero mass).

> What YOU stated was that the deflection depends on the
> assumed mass. It does not.
>
> YOU are the one claiming that a Newtonian calculation
> is possible which will show deflection, if you assume
> the right mass. Are you backing off of that?
>
No, I only said that if you can say that newtonian
gravity predicts half the correct angle, then I could
also say that newtonian gravity can predict the correct
angle if you assume the right mass for a fake photon.

> > Newtonian gravity is concerned
> > with neutral bulk matter, not with bosons.
>
> Newtonian gravity is concerned with anything with
> mass.
>

No. Newtonian gravity is not concerned with bosons,
regardless they are massless or not.

> > Even if
> > it were found out that photons have mass, newtonian
> > gravity would still remain without answers for them,
> > because they would still be bosons.
>
> ???
>
> And where are you getting this from?
>

This should need a new dedicated thread to
explain you where :-) . But, I'll give you a clue.
Pauli exclusion principle.

> So what's your point? Are you backing off your claim
> that the evil relativists goofed on the Newtonian
> calculation and if they did it right, Newtonian
> gravity would predict the correct deflection?
>
> Because that seems to contradict this post.
>
No, see above