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isospin
2006-Jul-24, 05:58 AM
Keeping a sample mass m constant and weighing/measuring in a vertical plane parallel to normal gravity, in a vacuum, using the Earth as a source mass M. An observation is made, due to varying one, and only one control variable which systematically has been found not to affect the measuring instrument in any way. After varying the magnitude of the control variable the sample mass weighs less within a few moments.
The experiment has been designed and carried out very carefully and all possible errors have been accounted for. Assume that this is a real effect not statistical in nature. m is constant and r is constant. Room variables are constant.

How would one approach this for a physical explanation? Would the G constant be varying? Or would there be some other force involved? Again, all errors have been accounted for.

Tim Thompson
2006-Jul-24, 03:11 PM
How would one approach this for a physical explanation? Would the G constant be varying? Or would there be some other force involved? Again, all errors have been accounted for.
The physical explanation will always be model dependent, as is your description of the experiment. After all, you don't know that the test mass m remains constant, you only assume that it does, and that assumption comes from some preconceived physical model you have for the experiment. In general, I would think that a varying G would not be a good explanation, since G is supposed to be a "universal" constant, and this experiment is not "universal" (but that too is model dependent, the model being that G is "universal").

In fact, what you describe looks very much like Podkletnov & Nieminen, 1992 (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1992PhyC..203..441P&db_key=PHY&d ata_type=HTML&format=&high=4366fa465118336), where they claimed to have shielded a test mass from the force of gravity (although Podesta & Bull, 2000 (http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1995PhyC..253..199D&db_key=PHY&d ata_type=HTML&format=), argue that this "effect" was only an artifact of their experimental setup).

One might also argue that, instead of shielding, an additional gravitational effect is at work (i.e., something like gravitomagnetism (http://scienceworld.wolfram.com/physics/Gravitomagnetism.html) or frame dragging (http://scienceworld.wolfram.com/physics/Lense-ThirringEffect.html) in general relativity (http://www-groups.dcs.st-and.ac.uk/~history/HistTopics/General_relativity.html)).

Again, how do you chose between claiming to have shielded or weakend gravity, or having seen the effect of an additional force? You decide by appealing to a preconceived model of the physics of the experiment. This is one reason why physicists rarely rely on one experiment like this, for definitive conclusions about physics. Rather, they rely on a suite of experiments, so as to cut down on the flexibility in choosing arbitrary models. Ideally, the experiment suite should be so restrictive that there is only one explanation, and one is not free to choose between arbitrary models. That is rarely the case in practice, but it is what you want in the end.

Ken G
2006-Jul-24, 03:55 PM
I agree with Tim, the issue is what was that control variable you were varying, and what is it plausible that it might have acted on. If it acted on the gravity itself, you could say that G is itself a function that can depend on other things that are usually not changing, or you could add additional terms added to normal gravity that depend on factors that are generally not present. Or, you could examine the possibility that the control variable acted on the mass itself, as Tim pointed out. Finally, you could assert that the control variable involved a second force altogether. This last possibility is by far the most likely in practice (magnetic or electrical forces, for example. Or the old magician's trick-- an unseen string).

antoniseb
2006-Jul-24, 04:19 PM
Hi isospin, welcome to the BAUT forum.

Tim and Ken have already given you some good answers. You were pretty vague about the specifics of the experiment, so there isn't much more that I can contribute.

In a very naive way, I wonder what the control variable could be that doesn't also affect the weighing equipment.

isospin
2006-Jul-24, 09:53 PM
Thanks for the replies, they're much appreciated!

The mass effect for the experiment was purposely made negligible through calculation and testing, and therefore mass can be assumed constant during this inquiry. The mass can be either metal or non-metal and the effect is still observed to a lesser or greater degree depending on the material used as a source sample. Several different experimental setups have been employed in efforts to negate the observed effect beginning in 1989; yet, results are similar in direction and magnitude. The current experimental instrument is of a flexure strip design based in part on the work of G. Gillies and C. Speake __I dont know the exact citation or reference off the top of my head. I can rule out any kind of possible gravitational shielding as the experiment is not setup in that manner. The effect is large ~ 0.1g +/- 0.004
This is the forth experimental design where each design, or experimental setup, was developed to negate all possible systematic errors. All known mechanisms, both vector and scalar, that could possibly mimic this effect have been examined and ruled out.

Im not at all claiming anything here. Big claims need big evidence, as well as, need conformation by other researchers. Im just puzzled. Either way, if we can assume for the moment that mass is held constant for this experiment then either there is some unknown error yet to be discovered, which I seriously doubt at this point, or g is somehow changed for the Earth-sample experimental system. I also doubt very much that the gravitative attraction that the particles have within the test sample for the Earth have changed unless either 1) the hypothetical graviton is made up more than a single entity one having a vector quality and the other having a scalar quality, or 2) the graviton for the test sample has somehow diminished. Either way, a change in G would be the result. Comments please?

Similar results can be found below if anyone is interested.

E. Fischbach, D. Sudarsky, A. Szafer, C. Talmadge, and S. H. Aronson, Phys. Rev. Lett. 56, 3 (1986).

R. v. Etvs, D. Pekr, and E. Fekete, Ann. Phys. (Leipzig) 68, 11 (1922).

P. Thieberger, Phys. Rev. Lett. 58, 1066 (1987).

P. E. Boynton, D. Crosby, P. Ekstrom, and A. Szumilo, Phys. Rev. Lett. 59, 1385 (1987).

publius
2006-Jul-24, 10:03 PM
Isospin,

Could you please describe here actually what is going on? What is being done, what control being varied, that causes this reduction in weight?

-Richard

isospin
2006-Jul-29, 09:16 PM
Richard et al.,

I'm not posting in this forum to make any claims whatsoever.

But I will say that if my observations are correct, relativistically speaking,
as a mass approaches the SOL, its inertial mass naturally increases and as a consequence of my observations, its gravitational mass would decrease. If that makes sense.

If in fact G is varying then Im not sure how to design a instrument that would test for this change without having many systematic problems to try to solve. I know the researchers at the NPL (University of Washington) that have, not so long ago, challenged the accuracy of the CODATA value for G using a plane of gold coated glass as their test mass etc.but this setup would not work for what I need to examine. Im thinking using the Earth as a source mass, thus measuring in a vertical plane parallel to normal gravity rather than using a torsional pendulum. I want to design an experiment that is convincing and not riddled with errors that I need to correct for to leach out the results.

Any ideas?

R.A.F.
2006-Jul-29, 11:54 PM
I'm not posting in this forum to make any claims whatsoever.

Ok...

But I will say that if my observations are correct...

That's not a claim??

isospin
2006-Jul-30, 01:49 AM
Well, MR R.A.F.

I was trying to answer a question without being too direct!

I'm not trying to play some sort of foolish game here. I'm just hoping that someone may have a suggestion.

And not to be unkind, but it's comments like yours that tend to encourage people doing real cutting edge research to keep to themself. So maybe I will too!

hhEb09'1
2006-Jul-31, 08:31 AM
I want to design an experiment that is convincing and not riddled with errors that I need to correct for to leach out the results.

Any ideas?I would first assume that G is not changing, and start there, to find your errors, rather than start with assuming G is changing.

isospin
2006-Jul-31, 09:24 PM
Hi hhEb09'1,

Thanks for the input!

First and foremost, I try not to assume anything. A varying G is the last and only possible explanation, and I really dont like the idea of having to buck a major cornerstone of science, the G constant. It makes me feel like Im some sort or rebel.

Also, I have been working on this problem for so many years, that I dont have a I have to be right notion built in to my character. Im only searching for the truth! All other possibilities have been exhausted long ago. Many researchers working in the area have also looked at what I am doing and how I am doing it, and they too do not have an explanation concerning my observations and are stumped. I had planned to publish my
results on several different occasions, but I always stop short asking myself How can this be? So I do more research and experimentation. Design a new instrument and start over and bingo, same results. Its consistent and reproducible, this I know for sure (a claim!).

I want to design an instrument that will be sufficient convincing with few systematic errors built into the design. And I will publish the results, even it they turn out to be null.

What I want from this forum are suggestions on how to test for a variation in G in a vertical plane parallel to gravity. And hopefully, a suggestion or two I havent thought of or that has already been suggested to me.

_Thanks

Ken G
2006-Jul-31, 11:11 PM
If you have already conducted several experiments of this nature, my guess is that you already have more practical expertise in this area than anyone on this forum. Why don't you publish what you already have and let the scientific community give you the feedback you desire, after all, that is what the scientific community is for. But if you really aren't comfortable with that and want to do another experiment, all I can tell you is that often the most clever experiments are designed to give an exact result of zero if there are no suprises. Zero is often the most precise measurement possible. So try to think of a way to get no response if the gravity gradient is according to Newton's laws, and watch out for the effects of local mass concentrations.

hhEb09'1
2006-Aug-01, 06:45 AM
First and foremost, I try not to assume anything. A varying G is the last and only possible explanation, and I really dont like the idea of having to buck a major cornerstone of science, the G constant. It makes me feel like Im some sort or rebel. I'd say, offhand, that you'd have a tough go ahead of you too, since there are many, many experiments that do not show the effect that you're describing. At least, as I understand your explanation.

Do you have an explanation for why you might be seeing this effect, while the others do not? I mean, are you doing these experiments under special circumstances, or at special times?

RussT
2006-Aug-01, 06:58 AM
Here is a question for everyone.

If, you added up 'all' of the 'mass' (gravity) of 'all' of the elements that make up the earth, would that weight (mass) equal what we say the earth weighs?

In other words, I don't think they measure the earth's weight (MASS) by adding all of its elements masses together, they determine the mass by a different method, so if you were to do it the way I suggested above, would it match?

Ken G
2006-Aug-01, 08:34 AM
To within our ability to measure, yes. Additional energy beyond rest energy is pretty negligible.

RussT
2006-Aug-01, 09:00 AM
Ken G, No, I'm not talking about the energy.

I am talking about adding up all the elements mass or weight.

Adding the weight's of all the atoms, in there different configurations from hydrogen to all the other heavier elements, together to get a figure for how much the earth weighs, and then comparing that to any other method of determining the earths weight. Do you think they would be the same?

Ken G
2006-Aug-01, 02:24 PM
Well, there's the rest mass energy that you are talking about (which accounts for the nuclear binding energy), and that's by far the dominant contribution. But for an exact result, you also have to add the heat, and subtract the binding energies, and then there's even a pressure term but that's really small for Earth, I'd imagine.

Tensor
2006-Aug-01, 07:58 PM
...there's even a pressure term but that's really small for Earth, I'd imagine.

It's even small for most stars, Ken. The pressure term is pretty much ignorable until you get inside something pretty massive like Eta Carina, something with a high density, like a white dwarf, or a neutron star, and even then, the relevance of the pressure term leans more toward the neutron star.

isospin
2006-Aug-01, 09:02 PM
The way I understand it, the mass of our planet, as with the mass of most all celestial bodies, is based on the G constant, primarily. That is, the gravitational influence the body exerts on nearby massive bodies such as within a planetary system, etc.. If we dont know the accuracy of the G constant then our basic understanding of the mass of the Earth or Sun is fundamentally incorrect.

Variation in the measurement the G constant spanning over 200 years

Data Set number Author Year G (x10-11 m3Kg-1s-2) Accuracy % Deviation
from CODATA

1 Cavendish H. 1798 6.74 0.05 +0.986
2 Reich F. 1838 6.63 0.06 -0.662
3 Baily F. 1843 6.62 0.07 -0.812
4 Cornu A, Baille J. 1873 6.63 0.017 -0.662
5 Jolly Ph. 1878 6.46 0.11 -3.209
6 Wilsing J. 1889 6.594 0.015 -1.202
7 Poynting J.H. 1891 6.70 0.04 +0.387
8 Boys C.V. 1895 6.658 0.007 -0.243
9 Eotvos R. 1896 6.657 0.013 -0.258
10 Brayn C.A. 1897 6.658 0.007 -0.243
11 Richarz F. & Krigar-Menzel O. 1898 6.683 0.011 +0.132
12 Burgess G.K. 1902 6.64 0.04 -0.512
13 Heyl P.R. 1928 6.6721 0.0073 -0.031
14 Heyl P.R. 1930 6.670 0.005 -0.063
15 Zaradnicek J. 1933 6.66 0.04 -0.213
16 Heyl P.,Chrzanowski 1942 6.673 0.003 -0.018
17 Rose R.D. et al. 1969 6.674 0.004 -0.003
18 Facy L., Pontikis C. 1972 6.6714 0.0006 -0.042
19 Renner Ya. 1974 6.670 0.008 -0.063
20 Karagioz et al 1975 6.668 0.002 -0.093
21 Luther et al 1975 6.6699 0.0014 -0.064
22 Koldewyn W., Faller J. 1976 6.57 0.17 -1.561
23 Sagitov M.U. et al 1977 6.6745 0.0008 +0.004
24 Luther G., Towler W. 1982 6.6726 0.0005 -0.024
25 Karagioz et al 1985 6.6730 0.0005 -0.018
26 Dousse & Rheme 1986 6.6722 0.0051 -0.030
27 Boer H. et al 1987 6.667 0.0007 -0.108
28 Karagioz et al 1986 6.6730 0.0003 -0.018
29 Karagioz et al 1987 6.6730 0.0005 -0.018
30 Karagioz et al 1988 6.6728 0.0003 -0.021
31 Karagioz et al 1989 6.6729 0.0002 -0.019
32 Saulnier M.S., Frisch D. 1989 6.65 0.09 -0.363
33 Karagioz et al 1990 6.6730 0.00009 -0.018
34 Schurr et al 1991 6.6613 0.0093 -0.193
35 Hubler et al 1992 6.6737 0.0051 -0.008
36 Izmailov et al 1992 6.6771 0.0004 +0.043
37 Michaelis et al 1993 6.71540 0.00008 +0.617
38 Hubler et al 1993 6.6698 0.0013 -0.066
39 Karagioz et al 1993 6.6729 0.0002 -0.019
40 Walesch et al 1994 6.6719 0.0008 -0.035
41 Fitzgerald & Armstrong 1994 6.6746 0.001 +0.006
42 Hubler et al 1994 6.6607 0.0032 -0.202
43 Hubler et al 1994 6.6779 0.0063 +0.055
44 Karagioz et al 1994 6.67285 0.00008 -0.020
45 Fitzgerald & Armstrong 1995 6.6656 0.0009 -0.129
46 Karagioz et al 1995 6.6729 0.0002 -0.019
47 Walesch et al 1995 6.6685 0.0011 -0.085
48 Michaelis et al 1996 6.7154 0.0008 +0.617
49 Karagioz et al 1996 6.6729 0.0005 -0.019
50 Bagley & Luther 1997 6.6740 0.0007 -0.003
51 Schurr, Nolting et al 1997 6.6754 0.0014 +0.018
52 Luo et al 1997 6.6699 0.0007 -0.064
53 Schwarz W. et al 1998 6.6873 0.0094 +0.196
54 Kleinvoss et al 1998 6.6735 0.0004 -0.011
55 Richman et al 1998 6.683 0.011 +0.132
56 Luo et al 1999 6.6699 0.0007 -0.064
57 Fitzgerald & Armstrong 1999 6.6742 0.0007 0.01
58 Richman S.J. et al 1999 6.6830 0.0011 +0.132
59 Schurr, Noltting et al 1999 6.6754 0.0015 +0.018
60 Gundlach & Merkowitz 1999 6.67422 0.00009 +0.0003
61 Quinn et al 2000 6.67559 0.00027 +0.021

-- PRESENT CODATA VALUE 2004 6.6742 0.001 0.0150