Re: Dark Matter

On 2 fév, 13:19, Igor <thoov...@xxxxxxxxxx> wrote:
On Feb 1, 3:54 pm, srp2...@xxxxxxxxx wrote:

On 2 f'v, 13:19, Igor <thoov...@xxxxxxxxxx> wrote:
On Feb 1, 3:54 pm, srp2...@xxxxxxxxx wrote:





On 1 f'v, 13:21, Igor <thoov...@xxxxxxxxxx> wrote:

On Feb 1, 12:48 pm, "Michael J. Strickland"

<qualityservic...@xxxxxxxxxxx> wrote:
I've heard that dark matter pervades the universe and I've heard
estimates that it accounts for up to 90% of the mass in the universe..

If this is true, why is this effect not seen in the orbits of the
planets
within our own solar system (which orbit in accordance with Newtonian
mechanics).

I would expect the additional 9 times more mass in the solar system to
severely perturb these orbits.

Since we do not observe this, what reasoning or phenomenon is
responsible for excluding dark matter from our solar system?

--

The same reasoning that excludes most of the rest of the matter in the
universe from our solar system. We simply do not observe any of its
effects within the solar system. So there's probably not very much of
it here, if it even exists. You need to understand that dark matter
is a hypothesis that supposedly fixes the notion that nearly all
galaxies are rotating much too fast for the observed stellar matter to
hold them together gravitationally against the centrifugal forces of
rotation. There are alternative hypotheses, but the jury is still
out.

There is also the option not considered yet that the galaxies may
well be much less massive than estimated. Not compatible with GR
though.

Andr' Michaud

I that's the case, why don't they just come apart due to centrifugal
forces?- Masquer le texte des messages pr'c'dents -

The orbits being stable, the the masses of the orbiting bodies
seem not to be relevant.

If you have the patience to follow the logic in this little piece of
mine up to the point leading to footnote 1 at the bottom of
page 4, you will see why this may be relevant.

http://www.wbabin.net/science/michaud1.pdf

At the real foundation, it would seem that it is the individual
particles individually, whatever the total macro mass of orbiting
bodies, that really are in orbit in the universe (not expounded on
in this little piece).

André Michaud
.

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