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Berkeley Lab Physicist Challenges Speed of Gravity Claim
spacedaily.com ^ | 23 Jun 03 | staff

Posted on 06/23/2003 9:25:12 AM PDT by RightWhale

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To: Physicist
Guess I'll just go eat worms...

ROFLMAO! Not until you tell us what "color" they are...

61 posted on 06/25/2003 1:20:31 PM PDT by Aracelis (Oh, evolve!)
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To: RadioAstronomer
One of the things that was discovered is that the mass of any nucleus is always less than the sum of the individual particles (called nucleons) that make it up. The difference (residual) is due to the “Binding Energy” of the nucleus. This binding energy is directly related to the strength of the strong force. Note: This is why there is a release of energy when an atom is split. (nuclear fission).

"Binding energy" is a negative energy. If the mass of a nucleus were always less than any sum of its potential components, then it would always take energy to split a nucleus. This is true for any nucleus below iron. For nuclei above iron, the binding energy becomes less and less; the strong nuclear force creates stable minima in which very heavy nuclei can exist, but these are but local minima sitting high on the electromagnetic hill. A uranium nucleus is heavier than thorium plus helium.

Doc Smith, in the classic novel Triplanetary, made the error of taking binding energy to be a positive, exploitable energy. Accordingly, the aliens used iron as fuel for their starships, iron having the maximum binding energy...sucking it, if necessary, out of the hemoglobin of human beings! In reality, iron is the one nucleus that can't be used for fuel, but I'm glad I didn't know that as a 12-year-old just the same.

62 posted on 06/25/2003 1:24:47 PM PDT by Physicist
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To: Physicist
Oh, so I'm a humorless cipher then, am I?

Around here, you have achieved Mt. Rushmore status.

63 posted on 06/25/2003 1:29:06 PM PDT by PatrickHenry (Felix, qui potuit rerum cognoscere causas.)
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To: RadioAstronomer
The attraction between the quark and antiquark is stronger than between just quarks.

I believe the attraction between them is the same, as they have the same strength of charge.

If it is a quark/antiquark (same color) it is called a meson. If its between quarks it is called a baryon (protons and neutrons fall in this category). Here is the rub, baryonic particles can exist if their total color is neutral; i.e. have a red green and blue charge altogether.

Both mesons and baryons are "colorless" with respect to the outside world. In baryons, as you say, red + blue + green = colorless. In mesons, for example, red + anti-red (or, if you like, red - red) = colorless.

64 posted on 06/25/2003 1:31:09 PM PDT by Physicist
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To: PatrickHenry
Around here, you have achieved Mt. Rushmore status.

Aw, great. Now Daschle represents me. Worms! More worms I say!

65 posted on 06/25/2003 1:33:19 PM PDT by Physicist
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To: Physicist
Oh, so I'm a humorless cipher then, am I? Guess I'll just go eat worms...

Surely you jest.....

;-)

66 posted on 06/25/2003 1:55:50 PM PDT by longshadow
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To: Southack
That is *precisely* what I said back in September here on FR, that all they were measuring was the propagation speed of Light, not Gravity.

Yes, but the reasons you gave for that announcement were goofy, IMNSHO.

Like the folks doing the experiment, you may have arrived at the right answer more by accident than via correct reasoning.

67 posted on 06/25/2003 2:00:00 PM PDT by Ichneumon
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To: RadioAstronomer
The quark interactions are cause by exchanging particles called gluons. There are eight kinds of gluons each having a specific “color” charge.

[Deep-Fried, Insufferable Geek Alert: there are three color charges, each with a corresponding anti-color. Every gluon carries both a color and an anti-color charge. Shouldn't there be nine kinds of gluon? Why are there only eight?

The combination red-antired + green-antigreen + blue-antiblue is colorless. Therefore, if I assign three gluons that are red-antired, blue-antiblue, and green-antigreen, I'm doing something redundant, because blue-antiblue (for example) is just 0 - red-antired - green-antigreen, and so forth. I'm using three vectors to span a two-dimensional space.

So what we do is choose two of the three color-anticolor pairs, and use them to compose two orthonormal basis vectors (such as g1=(red-antired + blue-antiblue)/sqrt(2), g2=(red-antired - blue-antiblue)/sqrt(2)), with the other gluons being g3=red-antigreen; g4=red-antiblue; g5=green-antiblue; g6=green-antired; g7=blue-antired; g8=blue-antigreen.]

[Atomic Wedgie Geek Alert: The symmetry group of Quantum Chromodynamics is SU(3). In the minimal representation of SU(3), there are three generators...the color charges. In the non-minimal representation, there are 3²-1 generators...the eight gluons! This was spookily mirrored by Murray Gell-Mann's original (1964) quark theory, which also exploited the SU(3) symmetry. Only this time, the minimal representation was the three light quark flavors (up, down, strange), and the non-minimal representation was Gell-Mann's famous Eightfold Way, which correctly(!) predicted the properties of all the light hadrons, including some that had not yet been discovered.]

68 posted on 06/25/2003 2:00:32 PM PDT by Physicist
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To: RightWhale
I think these guys are grasping at straws. Gravity is a force (Not a constant one either)therefore I don't think it has any speed. ie... The force of gravitational body (centrifugal) increases when an object moves away from it and decreases when a certain threshold of distance is reached away from that body. Gravity is still in effect, yet its influence is lessened by the corresponding distance away from the gravitational body. ( I am not a physicist and don't play one on TV) Just my two cents.
69 posted on 06/25/2003 2:05:25 PM PDT by semaj
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To: RadioAstronomer
So the dipole-dipole attraction is what is known as Van der Waals Forces. If these “particles” kinetic energies are low enough (anc close enough together), the repeated actions of the instantaneous dipoles will keep them attracted together. One of the interesting things about this that the more electrons are in play the greater the Van der Waals Force.

Trivia Of The Day: Because their foot pads end in literally billions of microscopic filaments, geckos use Van Der Waals forces to allow them to stick to just about any surface and climb up walls and across ceilings. They do this so efficiently that the average gecko is "glued" to the wall with about 200 pounds of force.


70 posted on 06/25/2003 2:07:02 PM PDT by Ichneumon
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To: semaj
Gravity is a force (Not a constant one either)therefore I don't think it has any speed. ie... The force of gravitational body (centrifugal) increases when an object moves away from it and decreases when a certain threshold of distance is reached away from that body. Gravity is still in effect, yet its influence is lessened by the corresponding distance away from the gravitational body.

The same argument could be applied to the force of electromagnetism, but electromagnetism conclusively propagates at the speed of light.

71 posted on 06/25/2003 2:09:07 PM PDT by Ichneumon
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To: 10mm
Not only does it propagate in waves, there are these tiny little quanta called gravitons that are the _______ of the waves. The deepest Physics is so metaphysical ...
72 posted on 06/25/2003 2:12:52 PM PDT by MHGinTN (If you can read this, you've had life support from someone. Promote Life Support for others.)
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To: semaj
Gravity is a force

It can't be that simple. Physicists would have nothing to do. You want to be responsible for all these physicists being out of work and on welfare?

73 posted on 06/25/2003 2:13:19 PM PDT by RightWhale (gazing at shadows)
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To: Ichneumon
Great Post!!

How cool is that?

Thanks.
74 posted on 06/25/2003 2:13:31 PM PDT by bondserv (Alignment is critical)
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To: Physicist
Have you ever gone to this site? It is quite funny. There is a bit at the bottom about how NYU Physics Professor Alan Sokal's brilliant (and meaningless) hoax article was accepted by a cultural criticism publication. They have a auto generator that will spew forth a random paper that means absolutely nothing. Priceless!!!


http://www.elsewhere.org/cgi-bin/postmodern
75 posted on 06/25/2003 2:22:15 PM PDT by Feiny
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To: PatrickHenry
Mt Rushmore status Placemarker
76 posted on 06/25/2003 2:24:29 PM PDT by Aric2000 (If the history of science shows us anything, it is that we get nowhere by labeling our ignorance god)
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To: RadioAstronomer; Physicist
>"The fundamental force is the inter-quark force that binds the quarks into hadrons (such as protons, neutrons and pions), and that is what we usually mean by the strong force, nowadays. The force between hadrons is a residual color dipole interaction that is analogous to the Van der Waals force in electromagnetism."

Cha, cha, cha... You know,
epicycles can explain
retrograde motion.

If you're willing to
pile complexity onto
complexity, you

need never give up
on Ptolemy's paradigm.
Sorry. Just rambling...

"So Ptolemy adopted an instrumentalist view --- this strange model is only an accurate calculator to predict the planet motions but the reality is Aristotle's model. This apparent contradiction between reality and a calculation device was perfectly fine in his time. Our modern belief that models must characterize the way the universe actually is [!] is a tribute to the even longer-lasting influence of Aristotle's realism."

77 posted on 06/25/2003 2:25:11 PM PDT by theFIRMbss
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To: Physicist
And for those who loe to complain:

http://escalus86.hypermart.net/complain.htm
78 posted on 06/25/2003 2:26:10 PM PDT by Feiny
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To: Ichneumon
The same argument could be applied to the force of electromagnetism, but electromagnetism conclusively propagates at the speed of light.

Van Flandern also now insists that electromagnetism propagates at infinite speed. (Not electromagnetic waves, mind you, but the field...whatever the devil that means.) It's nonsense, but he's forced into it by his own (mistaken) geometrical argument.

Presumably this frees gravitational waves (as opposed to fields) to propagate at c.

79 posted on 06/25/2003 2:27:01 PM PDT by Physicist
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To: Physicist
The complaint generator is not linking correctly.....so I found a better site for you:

http://www.ausmall.com.au/geek/geek5.htm
80 posted on 06/25/2003 2:31:19 PM PDT by Feiny
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