For starters, you might use the Equivalence Principle to measure off 1 "kg" on Titan. Then you might back that up with a spring scale set at 1 kg. Then count the molecules, or bring this new "kilogram" bar back to Earth and see what it is in our 1G, and compare its size and volume with the French bar.

I know, I know, the springs on Huygens.. etc. But don't put too much weight on that, since all those springs needed to do was RELEASE Huygens from Cassini, and then power Cassini out of there so it too wouldn't fall in to Titan. Once released, gravity did the rest, and Huygens made it into Titan's thick atmosphere, drag slowdown, parachute released, and it wobbled down to the surface... just as our friend Jerry described it.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

How would that work, exactly?

Spring scales measure weight (Newtons). How would I know when to stop putting matter on the scale? How many Newtons would the scale read when I had loaded 1kg on it and why?

If I count the number of molecules in the rod in France and find it is made up of X molecules, how many molecules would I count out on Titan to make a kilogram? X? If not X, why not?

Mass is not a function of volume. Many materials expand or contract (change volume) based on temperature. Obviously they are not gaining or losing mass based on temperature.

Why not? If the release did not work as planned I'm certain you'd point it out and imply it's evidence Newtonian physics is all wrong. Why doesn't the fact that the release was flawless count against your "variable mass" idea?

nutant
I'm sorry, but I don't understant your words. Let's talk again in numbers, if we could.

I would calculate the following:

1) Sun Mass: ~2 e 30 kg
2) G = 6.67e-11 m3 kg-1 s-2
3) Saturn gravitational mass: 5.7 e26 kg
4) Saturn inertial mass: 5.7e26 kg
5) Saturn dist from Sun (assume circle for now): 1.43 e12 m
6) Saturn "weight" (gravity force toward sun) = 3.7e22 N
7) Saturn acceleration toward sun: 6.52 m/s2

Could you calculate these seven numbers in your theory:
1) Sun Mass (I believe you said you agree that it's ~2 e 30 kg)
2) G : (I believe you said this is 66.7e-11, or 6.67e-10m3 kg-1 s-2)
3) Saturn gravitational mass
4) Saturn inertial mass
5) Saturn dist from Sun (assume circle for now)
6) Saturn "weight" (gravity force toward sun)
7) Saturn acceleration toward sun


No, that wasn't a typo --- you see, I still am not seeing why mass would change.

"Nough said. I've given you all the information you need to show how this works. I will reply only to specific errors in my math, or my reasoning. Work out your own math for any of the above. Please review my posts if you have further questions. Your repeating your questions, and I will not keep repeating my answers. Final word.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

The specific errors in your math have been pointed out quite ably by papageno. The key error is that you claim that if G is variable then the math shows that mass is also variable. Papageno correctly points out that they are two independant assumptions.

My questions were not repeats. They look similar, but the first set was designed to determine how, in your theory, mass, weight and acceleration are calculated for Objects around Titan in a (postulated) 10G environment. The second set of questions was designed to determine how, in your theory, mass and acceleration of Saturn around the Sun is calculated.

It should quickly become obvious that in order to correctly calculate Saturn's orbit around the Sun, you (in your theory) need to use the mass of the sun (~2e30 kg) and G = 1G (6.67 e-11 m3 kg-1s-2). Which means that an object at Saturn's orbit respond to the Sun's gravity as if G = 1G, but responds to Saturn's gravity as if G = 10G. This is patently absurd.

somehow, I suspect this isn't true either.

What about actually providing some math that shows the necessity/correctness of your "variable mass" idea? In spite of your efforts, there hasn't been a single calculation (using correct equations...) in this thread that shows "constant mass" failing in a variable G scenario.

And I suppose I'm not going to get an answer to my questions as to how you would suggest we measure 1kg of mass in 10G on Titan in your "variable G/variable mass" universe.

We've gone over every conceivable "hypothetical" variation of location and value for G in the solar system, and yet we have never had to redefine the kilogram to model what you say we should observe in a variable G universe...even when you've changed your mind on what you think we'd observe!

See this post, July 9, 2005, pg. 2 of this thread.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

Yes, I can see that post. That post is effectively debunked by

a) my analogous post regarding Saturn above, which demonstrates that you need G to be = 1G at Saturn's orbit to correctly calculate its orbital velocity.
b) Tassel's subsequent post on pg. 2 showing that you used the wrong mass in the equation "GM = rv2". You used M = mass of jupiter; in reality, M=mass of sun in that equation.

Note that we've pointed out an error in your mathematics, as per:
So would you now be able to answer my questions about Saturn's orbit? If you do, it will be patently obvious where your mathematical errors are.

RE: GM = Rv^2 for Saturn, it would be the same methodology as worked out for Jupiter here, July 11, 2005, pg. 3 of this thread.
(Please note that in the "short form", big M is now the planet, since the Sun's mass drops out from the "long form".) --this is wrong, M remains Sun's mass, will redo below to correct error. GM=rv^2 cannot be used for variable G, since Sun's G and M are invariable.--n.g.71

Taking Saturn's mass and distance from the Sun, adjusted for hypo 10G at Saturn:

Remember (critical point) neither Saturn's orbit nor its mass are changed, only how we measure the mass in terms of an increased G. So let's plug in some numbers for Saturn as we know them in (Earth's) 'universal constant' G, where G = 6.67E-11 m^3 kg^-1 s^-2 and Saturn's m = 5.685E+26 kg:

M * (Gm)/r^2 = mv^2/r, so that M*(6.67E-11 m^3 kg^-1 s^-2)(5.685E+26 kg)/ r^2 = m v^2/r, which is M*(37.92E+15 m^3 s^-2)/r^2 = m v^2/r

(Remember the right side is in Earth units, so does not change.)

Now let's plug in the new Saturn's G', tenfold, approxmately G' = ~66.7E-11 Nm^2 kg^-2:

M*[(~66.7E-11 m^3 kg^-1 s^-2) * m'] /r^2 = m v^2/r, and to conserve the product (G'm') = 37.92E+15 m^3 s^-2, divided by 66.7E-11 kg, m' becomes = 0.5685E+26 kg (which is one tenth the mass of what Saturn was in a G = 6.67E-11 N.. equation).

M, r^2, and mv^2/r remain the same as before. So we don't see any difference in Saturn's orbit with a different G. You cannot tell from the orbital "short form" GM=rv^2 because adjusted G' and m' are not shown, as they were canceled out in a 1G universal constant scenario. If you want to continue and plug in the M, r, r^2, in the "long form" you'll still get the same results as before.

The same applies to all the other values, since they are all derived from Earth's observations, so M and mv^2/r remain the same, figured in Earth units. Only (G*m) are adjusted for each other, while the Sun's "m" on the right side remains the same as it had been figured in the original. Why? Because all our math is derived from Earth based units of kilogram mass (as well as meters and seconds). If you were using Saturn based "kilograms", then you would not need to adjust (G*m) since it would all be figured "as if" that was the "universal constant" in its own kilograms. The orbital equation would still yield same, given the new units for G' and m'. It's just we seem to like Earth's G units for mass better, for better or worse. Consequently, our inherent "terracentrism" has given us a bias to believe G is a universal constant.

So the new orbital would be, for Saturn at hypo 10G:

GM = rv^2, plugging in the adjusted G and M (which is now Saturn):

(66.7E-11 m^3 kg^-1 s^-2)(0.5685E+26 kg) = rv^2

37.92E+15 m^3 s^-2 = rv^2.

Like I said before, you have all you need to figure this out. Whether or not you do, or whether you believe it, is up to you.

[Edited, for explanation of M vs. m, as Sun's mass, cannot use short form of G*M, also typo errors.]

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

Well, m' is 5.685E+25kg, but other than that, this is pretty much right.

The problem is, they aren't "Saturn Kilograms". They're just kilograms. If we were wrong about G at Saturn, and it is 10x higher than we think, then we have overestimated Saturn's mass by 10x. So, we recalculate Saturn's mass and it's 5.685E+25kg and we're done. We can now use that number for Saturn's mass in any equation we like.

I'm sorry, nutant, but this is where you go wrong. The Sun's mass does not drop out of the equation. It is Saturn's mass which drops out. See below.

OK, so let's solve for Saturn's orbital velocity. On average r = 1.4e12 m for saturn (see here.

Using your calculated value for GM (37.9e15 m3s-2) this gives v = 165 m / s, equivalent to an orbital period of about 1700 Earth years. This is wrong. Average orbital velocity for Saturn is ~9800 m/s for an orbital period of about 29 years.

Your math is wrong.

Right, GM = rv^2 does not work for a variable G, since M is the Sun's mass, which is invariable. So the "short form" as worked out above cannot be used for variable G.

I will go back into my above to work out the "long form" where a variable G shows up. As Sun is a fixed point of reference M, variable G does not apply. I'll get back when have some time.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

CORRECTED, long form for Saturn:


F = M(G*m)/ R^2 = mv^2/R

M(66.7E-11 m^3kg^-1s^-2)(0.5686E+26kg) = R(5.685E+26kg)v^2

M(37.92E+15 m^3 s^-2)/ (5.685E+26kg) = Rv^2

M(6.67E-11 m^3 kg^-1 s^-2) = Rv^2

… this is the correct representation of variable G for Saturn using the “long form”. Notice the right side mass for Saturn is in Earth kilograms in 1G (must equal the left side of equation), while left side is Saturn “kilograms” in 10G. Sir Isaac, that clever fellow, simply netted this out using a constant G, so he could make orbital equation in the short form.

If G proves to be variable, we are stuck using the long form. Same results, different conditions, which did not exist in Newton’s days. Since Sir Isaac knew nothing of gas giant atmospheres, or Pluto and Enceladus’s atmospheres, or netron stars super gravity, nor of the Pioneers anomaly, though I am sure he would have relished 21st century astronomical data, he had little reason to tamper with his universal G. Given what we know already, and yet to discover, there is no need to keep ourselves stuck in the 17th century forever, especially if G is found to vary in the universe.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer

edited whole message to reword:
Gee -- funny how that works. By twisting and turning your theory (and violating the equivalence principle in equation 2, by the way) you ultimately provide to us OUR equation, which is that
M-sun * G = r(saturn) * v(saturn)^2

Where G = a nicely constant 6.67e-11 m3kg-1s-2.

edited a second time to remove editorial comment

Not so.

1 Saturn “kg” (@10G) = 10 Earth kg @1G), where each molecule in Saturn’s 10G has ten times the “gravitational draw” and “inertial mass” of an Earth’s 1G molecule. This is a fundamental tenet of variable G, equivalence is never broken. Saturn’s 0.5685E+26 “kg” is still equivalent to Earth’s 5.686E+26 kg; it would take the same force to move 0.10 ”kg” on Saturn as it would take to move 1.0 kg on Earth. But if you want to move 1.0 “kg” on Saturn, you’d better be ready with 10 times the force.

And yes, as I explained before, the orbital parameters are not affected, nor is the inverse square law violated. The only difference is that it would take fewer molecules on Saturn to make the same mass on Earth. If you take 10% of platinum-iridium from Saturn and test it against the Equivalence Principle, you would discover that in 10G, it behaves as if it were 100% of Earth’s equivalent platinum-iridium matter. The molecules were never “lost”, but were never needed in the first place.

A natural question arises: What is the best way to test for variable G, using the Equivalence Principle, away from our 1 AU?

Can we go to Mars, at 1.5 AU, and see a measurable difference in G? What kind of experiments should be designed to test for this. Assuming we can’t bring back samples (at this time) and can only use remote sensing instruments to register anomalous G readings, what instruments should be sent over there?

That’s the next level.

__________________
Credibility is simply incredible... sometimes even to me.
disclaimer