We may not need a low temperature superconductor to slow the speed of light to get the (index of refraction)^4 amplification of applied stress-energy tensor's ability to warp spacetime. Click here.
On Aug 12, 2011, at 10:20 PM,
Gentlefolk,
...
I don't have much to report on the smaller list conversation of Mach effects. From my perspective, it seems that one of the major stumbling blocks has been the fact that Mach's principle has a long and sometimes colorful history that complicates and confuses any attempt to invoke it in physical arguments.
Yes, the only Mach's Principle that makes sense to me is our future event horizon as the hologram screen with a Wheeler-Feynman type retrocausal "back from the future" creation of everything (all matter fields including gravity) as bootstrapped post-selected hologram images. I suppose this requires a block universe picture with Novikov self-consistent loops in time.
People get fixated on, for example, the eight versions that Rovelli mentions (in the quote Jack circulated) or the dozen versions that Bondi and Samuel mention in their 1997 paper, and so on. The fact that GRT is a local field theory that has well-known anti-Machian solutions doesn't help either. If you want to put Mach's principle to use, you have to isolate the essential physical content of the principle and strip away all of the contentious arguments that, for practical purposes anyway, are distractions. That essential physical content is the claim that all inertial reaction forces are gravitational forces. In a way, this should be quite plausible, for gravitational forces, like inertial reaction forces, are "fictitious" in the sense that because of their behavior and universality, they can be geometrized away. This is just the EEP. But I've already said more on this than I intended. And I don't want to trigger another deluge of emails. . . . :-)
On other matters, the NASA NIAC awards were announced this past week. These are the "cross cutting", "revolutionary", "interdisciplinary", "paradigm shifting" projects that NASA hopes will radically change our future. It's an interesting collection.
The 100 Year Starship program, with a meeting in Orlando at the end of September, also notified those selected to be presenters and panelists this past week. At least one or two of you will be involved, and the meeting appears to be an interesting event. I hope that those of you who go to the meeting will share your experiences with the rest of us.
As you know, Jack has told us that he will be presenting his superconductor/metamaterial scheme at the 100YSS convention. And it's no secret that I've expressed some skepticism about that scheme. Jack challenged me to "run the numbers", and I have done so. That run is in the attached word document. I apologize for the slightly convoluted way of running the numbers. But the bottom line is that if the coupling coefficient in Einstein's equations really does contain n^4 as Jack claims, then realistic energies for incident EM radiation should produce some very startling effects in superconductors. Indeed, if his conjecture is right, some startling effects probably should already have been seen. In any event, since these are experiments that are doable, looking for Jack's predicted effect should not prove excessively difficult, or prohibitively expensive.
On the Mach effect front, ...I've managed to get several PZT stacks built using the new crystals purchased from Steminc last spring. Two of the stacks are nearly identical in configuration to the old stacks. They differ in the stiffness, dissipation, and dielectric constant of the material. And the stacks have three accelerometers, where the old stacks only have one. There are some pictures in the PPT file attached. In addition to the two stacks just mentioned, a short stack is nearing completion in anticipation of going to higher frequencies. Sometime soon.
I trust all is well with you and yours,
Jim
RUNNING THE NUMBERS
by James Woodward
"The field equation is:
Guv = (8piG/c^4)Tuv
And the coefficient of Tuvi n cgs units is 2 X 10-48. We know that a Jupiter mass (2 X 1030 gm) of stuff will produce serious warps, so we set T = mc2 getting 2 X 1051 ergs. Multiplying by the coefficient, we find that the RHS of the field equation has the value 4 X 103 for the case of a Jupiter mass of stuff.
Now, in the case of laser light propagating through a superconductor, we make some modest assumptions. We take the power of the laser to be a milliwatt, and the duration of the affected pulse to be a millisecond. Since there are 107 ergs in a joule, the energy of the pulse deposited in the super conductor will be 10 ergs.
We next implement Jack’s proposal and assume that there is an n4 = 1 X 1040 in the numerator of the coefficient. This makes the coefficient = 2 X 10-8, and with Too = 10 ergs we have 2 X 10-7 for the RHS of the equation as compared with 4 X 103 for Jupiter. To get the effective mass of our 10 ergs in the superconductor – at least as far as the local geometry is concerned – we simply take the ratio of these numbers and multiply it times the Jupiter mass. That number turns out to be 1 X 1020 grams. Were the “effective” mass to act like a real mass, 1 X 1020 grams is enough to produce serious disruptions in any realistic lab. Arguably this should be the case as the electromagnetic radiation is strongly coupled to the superconductor’s constituent material structure.
Nonetheless, we aren’t talking about real mass. We’re talking about geometric distortions of local spacetime. What does it take to produce serious spacetime distortions at laboratory scale? Well, the event horizon condition for a black hole is:
R = 2GM/c^2
And for R to be on the order of 10 meters or so, not surprisingly, we get back a Jupiter mass for M. So, to produce a meso-scale black hole in the lab, we would have to increase the 10 ergs by 10 t0 11 orders of magnitude. So, we’re talking about 1 to 10 kilojoules being deposited in our superconductor to produce serious spacetime warps. While it is doubtful that the superconducting state could be maintained in the presence of several kilojoules of energy in a region with a typical dimension of a centimeter or so, a few kilojoules of energy is by no means an unreasonable amount of energy. So, testing the proposition that the coupling coefficient in Einstein’s field equations depends on the index of refraction of any medium present should be a tractable problem if the technical problem of the deposition of a large amount of energy in a superconductor without disrupting the superconducting state can be managed.