Re: is perpetual motion possible ?

Rob wrote:
"Kyle T. Jones" <KBfoMe@xxxxxxxxxxxxxx> wrote in message news:g5g5p6$ko2$1@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Rob wrote:
"Kyle T. Jones" <KBfoMe@xxxxxxxxxxxxxx> wrote in message news:g5076d$tp8$1@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
Rob wrote:
"Kyle T. Jones" <KBfoMe@xxxxxxxxxxxxxx> wrote in message news:g4vuiv$5c9$1@xxxxxxxxxxxxxxxxxxxxxxxxxxxx
At first blush, I thought your "thought experiment" relied on assuming my hypothesis was false, then simply writing what you'd expect to happen given that assumption. Begging the question. That was the basis of this response.

At second glance, I realized that the results of your experiment would be the same under either system, and that you had misunderstood those results. Thus the second response.

Cheers.
Not at all. If gravity is attractive, two masses inside an evacuated sphere will experience an attraction which is independent of the proximity or composition of the sphere walls. If vacuum pushed, this is not true. In fact if the distance between the masses is greater than the radius of the sphere, the masses will be pushed apart in your model.
Not at all. You make some hidden assumptions here, Rob. For one, you assume that the sphere completely blocks/absorbs all the repulsive energy coming from the vacuum outside that sphere.
Whatever percentage it blocks/absorbs will depend on the thickness. Thus the force on the test masses is dependent on the wall thickness.

You can say "not at all" a million times, Rob. The truth is that the math is the same in either case. If you make the walls of the sphere massive enough to block the "repulsive" force completely, resulting in "the masses will be pushed apart in your model", you've made them massive enough so "the masses will be pushed apart" in your model as well (because you've made them massive enough that they are now "attracting" in your model).

Cheers.
Ah. I see the problem now. I gave you credit for more knowledge than you actually have.
So, lets try again. The walls of a hollow sphere don't attract anything inside it. It does not matter how heavy the walls are. Or how big the sphere is. Or where in the sphere the masses are. Now that you know this, go back and reread your last paragraph and admit defeat.

Cheers.


Actually, I take back even the mildest gesture of defeat.

You're "phenomena" is merely a mildly interesting "trick", that would give the same results under either interpretation.

In other words, a hollow sphere will be gravitationally neutral in the context of objects inside that sphere, regardless.

Perhaps I gave you too much credit, and started doubting the obvious: that saying mass attracts is exactly the same as saying non-mass repels.

For homework, see if you can work out why the sphere is also gravitationally neutral under my interpretation; let's see, here's a big hint: it's gravitationally neutral under your model because as the object moves/is moved closer to one side, there is more sphere mass on the other side.


Clueless.

You certainly are. A living testament to the idea that just a little bit of knowledge can be a dangerous thing.

The sphere is graviationally neutral because of symmetry, leaving the gravity test masses inside as the only force operating. Your system is not symmetric because the effect of the vacuum _outside_ the sphere is different from that within.


The two interpretations are identical. Outside gravitational influences are in effect under both. There, I've given you three big hints.

IOW, the force 'pushing' the test masses together comes through the sphere from all directions, and the masses move towards each other because of this. There is also the force of the vacuum between the test masses pushing them apart. If you double, triple, whatever the sphere mass, less of your mythical pushing force gets through, but the push from between the test masses stays constant.

Ahh, I see where you are making the mistake. It's right here. You haven't really understood anything I've said, have you?

The force between the test masses is thus dependent
on the mass of the walls, in your model. So, in your model, the sphere is NOT gravitationally neutral.
Note that if you make the walls thick enough to completely stop the vacuum push force, test masses set further apart than the inner radius of the sphere will repel each other, as the vacuum between them pushes them apart.
I think it's tme to give your mythical force a name - since the standard force is called 'gravity', I would suggest 'levity'.

Here's another big hint: the math, in every instance, is the same under both interpretations.

Cheers.

Since you have no equations to describe your model, there is no math under your interpretation. Your model is indeed repulsive.

Rob.



For the tenth time, the math is identical. It's hard for me to believe this is too complex for you. Look, make a gravitational map of the solar system. If the mass in this region is such and such, you make such and such size dent. If mass in another region is such and such, you make such and such size dent. Or, approach it another way: consider the greatest amount of mass, then describe regions in terms of falling short of that ideal; such and such region misses umass by this amount, so we elevate that portion of the map to such size; the other region misses umass by some other amount, so we elevate the portion of the map to some other such size. In the end, you have the same map. It isn't difficult, Rob. It takes just the smallest ability to think outside the box, though. Perhaps that's what yer lacking.

Good quip, though.

Cheers.
.

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