I've already mentioned two of the program items I was on at Boskone (global warming and quantum physics for dogs). I should at least comment on the other two, "Physics: What We Don't Understand" and "Is Science Addicted to Randomness?" They both featured me and Geoff Landis, but other than that were very different.
"Physics: What We Don't Understand" took off from a column by John Cramer from ten years ago, laying out seven big problems in (astro)physics that hadn't been solved. We talked about how some of Cramer's items have been more or less solved (gamma-ray bursts, solar neutrinos, and ultra-high-energy cosmic rays), what he left off (unification of quantum mechanics and general relativity, problems in quantum measurement and information, high-temperature superconductivity), and a variety of other issues (this is where Gravity Probe B came up, for example).
It was a good deal of fun to be on the panel-- when Karl Schroeder is the least qualified (formally, anyway) person on the panel, it's bound to be an interesting conversation-- and the audience seemed to enjoy it. I think my favorite result was the Landis Criterion for evaluating speculative theories: Geoff said his rule was to believe in whichever of two competing theories had the better potential for generating science fiction stories.
The "Addicted to Randomness" panel was Sunday morning, moderated by Greg Bear. I did manage not to do the pathetic fanboy thing on meeting him, and talk about how much I loved his books twenty-odd years ago, but it was close. The whole panel turned out to have been his idea, which was both good and bad.
The good part was that he had a clear idea of what the point was supposed to be, and where he wanted the panel to go. The bad part was that I had no idea where that was, so I had a bit of a hard time figuring out what it was that we were supposed to be talking about.
A good deal of time was spent trying to make a clear distinction between "knowledge" and "information," aided by an audience member who, if I didn't know better, I would've guessed was Jonathan Vos Post. Many of the arguments seemed to me to be awfully circular (Bear would say that knowledge was information that had been processed by a biological system, and then assert that only biological systems had the ability to use knowledge to improve their lot in life), but people seemed to be really getting into it, so I mostly shut up and let them proceed.
I think the whole thing was primarily about biology, and thus it was a shame that we didn't have any biologists on the panel. Bear seemed to be arguing that some biological process that we take to be random are not, thanks to the ability of living things to process information into knowledge. There was also a big thing about kin selection toward the end, but my knowledge of the subject is barely enough to recognize "kin selection" as fighting words in a biological context, so I stayed clear.
I'd be interested in hearing what the audience thought of this one. I was pretty groggy (my current cold/ bronchitis thing was ramping up big time), and perhaps too involved in the details to figure out if there was any coherent message from the whole thing.
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I thought Bear's randomness lecture was pretty cool, but I felt bad for the rest of you who had been told it would be a panel discussion.
My take (which I piped up from the audience at one point) was to shunt the circularity (and Bear's IMHO erroneous focus on biochemistry) over to evolution, which only sounds circular if you try to distill it down to two sentences. "Knowledge is information being operated on by an evolved system; evolution proceeds by incorporating information about the environment into the system (to make it work better)." That's circular on its face, but we have a good idea of what evolution is, so you can read the relation as illuminating the notion of knowledge. And connecting it with intentionality, since we *also* have a good notion of how to talk about the "intentions" of an evolved system (without getting snarled up in "free will" or "consciousness", thank you Dennett).
I think that's a nifty philosophical point, and certainly SF novels have been built on weaker ones.
First, I heard someone complain that Greg Bear's molecular evolution facts were wrong in his fiction (I think we were aboard the pirate ship party at a worldcon). I waited until he finished flaming, and then gave refereed citations to validate Greg Bear's claims. Ditto, I've seen emails disputing Geoff Landis on fine points of Quantum Mechanics. Geoff is utterly polite and helpful, up to the point when the other party reveals deep crackpottery/trolling, at which point he politely disentangles. AND YET, at a con panel, there are people in the audience who never really believe any professional SF author, regardless of professorship or publication credentials. And, once in a while, we don't believe each other.
I liked the randomness panel at the beginning ten minutes or so, when it discussed whether physics was addicted to randomness-- this seemed an interesting question to me. Bear then moved it very quickly to the question of the role of information in biology, which I found less interesting. Not that information in biology isn't intersting, but it wasn't the panel I was prepared for.
Would have been a better panel had it been simply a lecture (and Q&A) by Greg Bear, I think-- it was the topic he was prepared, and a lot of his moderating seemed to be trying to do the socratic method on the audience (i.e., already know the answer you're looking for, and attempting to lead the audience into coming up with it "on their own").
Dear Editor. The following information may be of interest to your readers.
Strong Evidence for the Slow Secular Decrease of the Gravitational Constant G
Dr. Gerhard Löbert, Otterweg 48, 85598 Baldham, Germany. March 2009.
Physicist. Recipient of The Needle of Honor of German Aeronautics.
Former Program Manager Lampyridae (see Google "Gerhard, Lampyridae")
Conveyor of a super-Einsteinian theory of gravitation that not only covers the well-known Einstein effects but also explains, among many other post-Einstein-effects, the slow secular decrease of the gravitational constant.
1. Geophysical and Astrophysical Evidence
1.1 The existence of extensive near-horizontal beds of sedimentary rocks on the surface of all continents that originally were formed below sea level
Due to the extremely high core pressure, celestial bodies of the mass and radius of the Earth experience an extremely high elastic compression of the core. If G were to decrease slowly with time, the core of the Earth would decompress (i.e. expand) slowly, the Earth radius and surface area would increase slowly, the crust would develop cracks of increasing width, the oceans would enter these rifts, the area of the oceanic crust would increase steadily, and the sea level would drop slowly, so that most areas of the continental crust would ultimately fall dry. Rock beds that were formed below sea level would ultimately be located above sea level.
A simulation of the elastic Earth with different values of G shows that the Earth radius varies with the tenth root of 1/G, approximately.
Thus, the present vertical locations of extensive regions of near-horizontal sedimentary rocks on all continents are a clear indication that G must have decreased since the time these rock beds were formed below sea level.
According to the new theory of gravitation described in Section 2, the gravitational force acting between two particles, which is determined by G/c²c², varies with t, the time measured relative to the big bang epoch, as t raised to the power -1/4.
1.2 The slow secular increase of the orbital radii of all planets
The paleoclimates of Mars and Earth were very much warmer than today. Three billion years ago, the oceans on Earth were 30 ° C warmer than today. Thus, at that time Earth must have been considerably closer to the Sun than it is today.
Presently, the mean surface temperature on Mars is about -60 ° C. As the large, integrated, mature water drainage systems of Mars show, that planet must have harbored large amounts of water and the mean surface temperature must have been above 0 ° C in the distant past. Consequently, at that time Mars must have been considerably closer to the Sun than today.
Gravitational theory shows that orbital radius increases with decreasing G. Thus, the increase of the orbital radii of Earth and Mars indicate that G must have been considerably higher in the distant past than it is today.
The new theory described in Section 2 shows that the orbital radius of all planets varies with t as t raised to the power 1/2.
1.3 The unacceptably old age of many low-luminosity stars
If one calculates the age of low-luminosity stars on the basis of a time-constant gravitational constant, one gets the embarassing result, that some stars seem to be older than the universe. If, in the distant past, G had been considerably higher than it is today, the true age of a star would be considerably smaller than the age calculated with time-constant G, since stellar luminosity and fuel burning rate vary in proportion to a high power of G. The age discrepancy shows that in the distant past G must have been much higher than it is today.
The new theory described in Section 2 shows that a star, whose age had previously been calculated to be equal to the age of the universe, has in reality only about 50% of this age.
1.4 The increase of the mean luminosity of galaxies with increasing redshift
Theoretical physics gives the result that, if G were variable, the luminosity of a star would increase proportional to a very high power (of the order of 7) of G. The increased mean luminosity of galaxies in the distant past shows that G must have been considerably larger at that time.
1.5 The disappearance of water on Mars
The large, mature water drainage systems on Mars clearly show that in the distant past this planet habored huge amounts of water. For a planet of this size, this was only possible if, at that time, G was very much higher than today, so that water vapor could not escape into space.
In the mean time, Mars has lost most of its water (water vapor) due to the secular decrease of G. In contrast, Earth, with its 5-fold escape energy, has been able to bind water vapor up to now.
1.6 The travel times of signals reflected from a planet
The new gravitational theory described in Section 2 gives the result that the travel time of a signal reflected from a planet should increase slowly at the rate of approximately 0.02 parts-per-billion per year. This low value results from the fact that the speed of light is increasing almost at the same rate that all orbital radii are increasing. Because of this small value, it would be very difficult to detect a secular travel time change.
It should be noted that the new theory has a free expansion parameter that can be chosen such that c and the orbital radii have the same relative secular change, so that signal travel time would remain constant.
2. Theory
The currently favoured gravitational theory, the General Theory of Relativity (GR) of Einstein, is pre-quantum-mechanics, purely geometric, and deviates from reality by at least 41 orders of magnitude (see Weinberg, S.: Rev. Mod. Phys. Vol. 61, 1989, p. 1). Definite proof of the fallacy of GR is provided by the Casimir experiment in which a vacuum energy density of 0.03 J/m³ has been measured. With this energy density, which is more than 8 orders of magnitude higher than the mean density of the rest energy of the visible matter content of the universe, GR gives a universe age that is three orders of magnitude smaller than the age of the Earth!
As a logical consequence, GR must be replaced by a theory of gravitation that is in line with modern particle interaction theory and is in good agreement with experiment. The author has developed such a new theory. This theory, which is based on quantum mechanics and on two plausible post-university-teaching assumptions, not only covers the well-known Einstein effects but also describes a number of post-Einstein-effects that have shown up in recent geo- and astrophysical observations.
The first assumption is founded on the fact that in the documented particle accelerator experiments, all particles have displayed a dynamic behaviour identical to that of equal-energy electromagnetic radiation enclosed in a vessel with perfectly reflecting walls. Hence, not only photons but all elementary particles must - with high probability - be of an electromagnetic nature. They can be represented by non-radiating oscillating multipole fields carrying energy and angular momentum suitably combined with electrostatic fields.
Every force field requires a carrier, either in the form of a substrate or a mediating particle. Generations of electrodynamicists have disregarded this simple wisdom. It is here assumed (second assumption) that electromagnetic fields are carried by a dense sea of polarisable and magnetisable subphotonic particles of extremely low mass called "seaons". This seaon sea fills the complete universe and is presently expanding from its initial state of infinite particle density at the time of the big bang. The gaskinetic particle motion within the Sun on the one hand, and the dynamics of galaxy clusters and superclusters on the other, yield a seaon mass of some 10**(-33) neutron masses.
The quantum-mechanical interaction of the seaons with the electromagnetic field of a material particle of mass m1 results in a spherically symmetric increase of the local seaon particle number density and, as a consequence, in a spherically symmetric reduction of the local speed of light of the form c(r) / cinfinity =
1 - G m1 / (c²r). (Here c is the distance travelled by light in one unit of local time). Because of the gradient in c, a second material particle of mass m2 and electromagnetic energy m2c² placed in the c-field of the first particle experiences the well-known electromagnetic gradient force F = (m2c²) grad c / c = G m1 m2 / r².
The new gravitational theory is called Seaon Theory (ST). It displays a number of post-Einstein-effects that are not covered by GR. In this Note the post-Einstein-effect of the slow secular decrease of the gravitational constant G is addressed. The other post-Einstein-effects are described in Ref. 3.
As a result of the steady decrease of the particle number density in the steadily expanding seaon sea, the electromagnetic properties of the vacuum, the speed of light, the gravitational "constant" and many other physical quantities change slowly with time.
In Ref. 1 it is shown that c varies with t as t raised to the power 1/4. The gravitational force acting between two particles, which is proportional to G/c²c², varies with t as t raised to the power -1/4.
3. References
1. Löbert, G.: A new theory of gravitation and its impact on cosmology; stellar evolution; galaxy dynamics; the power source of stars, coronas and intergalactic gases; supermassive/superdense bodies; cosmic jets; and the generation of longitudinal gravitational (vacuum density) waves and their action on the Sun and the Earth (e.g. world climate). Munich 1993.
2. www.icecap.us/images/uploads/Lobert_on_CO2.pdf
3. The last post in Google "Gerhard, pakteahouse"
Entropy is one of Physics Foibles. Use a random number generator to view probability (Entropyâs twin).