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Plant Sciences, Zoology & Evolution / Is there any such thing as animal "culture" ?

« on: 22/02/2009 23:10:48 »

It's common knowledge that animals removed from the wild at a young age will not survive if returned to the wild at a later age even if they remain healthy. This is particularly true of mammals. Mammals must be allowed to absorb the 'culture' of their species. I've never heard the word 'culture' used this way, but it seems appropriate. It seems the higher up the evolutionary scale, the greater the role of culture in survival. If this is the case, than genetics appears to play a diminishing role in survival and therefore the direction of evolution. Any views on this?       

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Physics, Astronomy & Cosmology / net energy of the universe is zero?

« on: 04/02/2009 22:55:41 »

Stephen Hawking and others have proposed that the net energy of the universe is zero by considering gravitational energy as negative, and all other energy forms as presumably positive (or possibly neutral?). On the surface, this sounds wacky to me. Even QM doesn't truly get something from nothing. Particles can condense out of energy fields and particles can be transformed into their energy equivalent through particle-antiparticle annihilation, but energy is always conserved. I understand that in cosmology, the stress-energy tensor of GR is what's conserved, not necessarily matter-energy. Does that mean that the total energy of the universe is conserved or do we really get something from nothing?

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Physics, Astronomy & Cosmology / Bose-Einstein condensates and lightspeed

« on: 01/01/2009 21:42:28 »

Light has been shown to be slowed dramatically in Bose-Einstein condensates (BEC-a quantum state existing very close to absolute zero.) What does this say about lightspeed as a constant? How does this affect the interpretation of the Lorentz factor? Does time "stop" for a light beam moving at only a few cm/sec?

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Geek Speak / How do genetic algorithms work?

« on: 11/10/2008 21:58:12 »

I'm not a computer guy, but I'm fascinated by genetic algorithms. These programs apparently can evolve rapidly toward near ideal solutions for a given computable problem. I've read that designs produced by these algorithms can be better than, although often very different from, human designs for a given set of specifications. I see this as a kind of "compressed" evolutionary process which suggests that evolution, when greatly compressed in time, looks like an intelligent process. Does anyone here know more about these remarkable programs? I'm aware of "Life" type programs and Stephen Wolfram's work with virtual computable structures, but genetic algorithms are designed to be goal oriented; solving real problems.   

_{Mod edit - Formatted the subject as a question - please do this to help keep the forum tidy and easy to navigate - thanks!}

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Physics, Astronomy & Cosmology / Do photons have energy equivalent mass at ight speed?

« on: 29/09/2008 23:59:13 »

Special Relativity (SR)says that the mass of a particle will increase with its velocity according to the Lorentz transformation. Photons have no rest mass but photons always travel at light speed. General Relativity (GR)states that gravity can bend a light beam, and this has been observed. GR explains this in terms of the geometry of spacetime. Quantum mechanics (QM) proposes the graviton as the carrier of the gravitational force. As such, it interacts with particles with mass. However it's clear from E=mc^2, it seems that if m=0, photons have no 'energy' at light speed or energy equivalent mass. If rest mass is zero, it seems photons cannot acquire mass by virtue of moving.       

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Plant Sciences, Zoology & Evolution / Can dogs breed with foxes?

« on: 16/09/2008 06:30:05 »

I've always understood that the definition of a species is that its members can interbreed, but cannot breed with other species. In the case of canines, wolves ('canis lupus') and domestic dogs ('canis domesticus') can interbreed. Apparently some domestic dog breeds can, or used to able, to breed with foxes (vulpes fulve) which are a different genus. Does this mean that biological taxonomies are not as sharply defined as many believe? 

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Plant Sciences, Zoology & Evolution / Can changing the rules damage dogs' learning ability?

« on: 14/09/2008 22:41:47 »

I've been told that dogs can become confused and neurotic when the rules are changed. For example, a dog allowed have its own space in the house for a while, and later is "evicted". The rules are laid when when dogs are puppies, but later, if some rules are changed arbitrarily the dog actually looses some of its ability to be retrained. Is this true? I'm not talking about old dogs, but dogs over about one year old.

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New Theories / Another view of "intelligence"

« on: 11/09/2008 01:35:57 »

This is not a new theory, but simply a view on what the word "intelligence" actually means or seems to mean. In artificial intelligence(AI) research the Turing Test definition is still the standard, a least in terms of whether a machine can actually fool a human that it itself has 'human style' (ie Turing Test) intelligence. The Turing Test (first proposed by Alan Turing in 1951)is fairly straightforward. A human subject carries on a conversation with another human and machine under blinded conditions. There are many ways to carry out the test in terms of study design. The idea is that after interviewing a human and a machine, the human subject cannot discriminate between the two, this is a point for AI. In Turing's time, the interviews could only be carried out by text or by a mediator. Today, human voice simulation is quite good, but perhaps not good enough not to give the test subject clues regarding voice inflections, tones, etc. In any case, the fundamental assumption was, and still is, that our notion of intelligence is subjective and is simply a quality that a being, who is assumed to have intelligence, can recognize in another.

If we were to encounter possible evidence of extraterrestrial intelligence (ETI), how would we evaluate it? How do we determine whether some feature or object is the product of an intelligence. (By the way, if you sense that I'm going off on some "intelligent design" track, I'm not. Just the opposite.) Essentially, the question we must ask is: What is the probability that this object or feature is the result of some "natural" process? Of course, determining probabilities requires some knowledge of the process and the distribution of outcomes. I argue that if we want to use the term "intelligence", it seems that it must be based on the assessment that the existence of an object or feature is of negligible probability in the absence of intelligence; GIVEN OUR KNOWLEDGE OF THE PUTATIVE PROCESS. By being predicated this way, the term "intelligent design" does NOT apply to biological evolution because we have an adequate, if not complete, theory of the process by which biological designs arose. On the other hand, if we found an object on Mars that could not be reasonably explained by any known or reasonably understood natural process, we might be forced to recognize the existence of ETI, assuming no prior human presence.

So far, so good. But consider that humans (and any ETI) themselves are the product of natural processes. I don't think there can be any doubt about this if you're a scientist. Therefore, everything that is the product of human (or any other) intelligence is also a product of natural processes. It's convenient to maintain the distinction between natural and artificial, but this is a false dichotomy. I argue that what we call intelligence, particularly technologically advanced intelligence, is in fact a phase of cosmic evolution, just as the appearance of intact atoms, stars, heavy elements, carbon compounds, and life are phases of cosmic evolution. These ideas are not entirely my own. Authors such as Ray Kurzweil, Vernor Vinge, Paul Davies, James Gardner and others have thought along similar lines, although my view that "intelligence" is simply a relative, and not particularly useful term based on a false dichotomy seems to be new. These ideas are further explained in my own book which is mentioned in my biography for anyone who might be interested.             

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Physics, Astronomy & Cosmology / What is the fine structure constant?

« on: 08/09/2008 20:32:53 »

I know the Sommerfield fine structure constant is an important fundamental physical constant and its value is about 1/137. What exactly is it? It's straightforward to grasp the meaning of constants like the speed of light, the masses of protons, electrons, etc. But what is a dimensionless 1/137? There seems to be some mysticism associated with this number based on a Google search.

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Plant Sciences, Zoology & Evolution / Could whole unexpressed structures be encoded in junk DNA?

« on: 04/09/2008 21:16:36 »

Since we don't know what 'junk' DNA codes for, is it possible that whole structures, like wings, could be encoded in animals that don't have wings? This would help explain sudden, rather than gradual, structural changes in the fossil record. Genetic regulatory mechanisms might derepress "junk" genes and allow their expression.

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Physics, Astronomy & Cosmology / Will the LHC find any strings?

« on: 03/09/2008 09:10:05 »

Will the LHC find any strings? If not, what are the odds of ever being able to test any string/M theory? Physicist Lee Smolin says there are 10^500 string theories ("The Trouble with Physics," Houghton-Mifflin, 2007). How do we know which one is correct? Maybe they're all correct and we live in 10^500 universes simultaneously. That could be confusing.

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Famous Scientists, Doctors and Inventors / Did Einstein steal HA Lorentz's idea?

« on: 31/08/2008 21:07:53 »

I'm a big fan of Albert Einstein, so I just wanted to clear the air about this. It is true that Lorentz, a Nobel Prize winner, published the equations of relative motion a year before Einstein. These equations still bear his name. Einstein's original contribution (E=mc^2)is actually derived by simply substituting the speed of light (c)into a Newtonian equation: E=mv^2.  So why does Einstein get all the credit? I think I know the answer, but I want to hear from others. 

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Physics, Astronomy & Cosmology / Why do we need gravitons?

« on: 31/08/2008 08:55:58 »

The graviton is the still unconfirmed particle carrier of the gravitational force. Why do we need it if gravity is already explained by General Relativity (GR)? Light has no mass. If it did, it could not travel at "the speed of light"(according to SR). GR explains the bending of a light beam near a massive body by the locally increased curvature of spacetime itself. Light is simply following the natural geodesic of spacetime. This explanation would also seem to hold for the gravitational attraction between masses.   

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New Theories / global warming can cause an ice age due to increased polar snowfall

« on: 29/08/2008 10:40:32 »

The usual proposed mechanism whereby global warming might trigger an ice age, or at least colder temperatures in some areas, has to do with decreased salinity of the oceans. Melting ice dilutes the seawater and thereby raises the freezing point from about -1.8 degrees C to perhaps -1.0  degrees C or more in high latitude seas. However, there is a more powerful mechanism which is rarely discussed. At present the polar regions are deserts. The deep interior of Antarctica receives almost no precipitation at all. The high Arctic receives most of its precipitation between May and September and much of that falls as rain or snow that melts. Northern Ellsmere Island receives less than 6 cm of precipitation annually.

With global warming the Arctic icepack melts. The temperatures in the Arctic rise and precipitation increases considerably. Much of it will fall as snow since winter temperatures will likely still be below freezing. Right now winter temperatures on the landmasses around the Arctic Ocean average around -30 C or lower.
If these temperatures rise to around -10 C to -5 C or so and the central Arctic Ocean is ice free (supplying more moisture), very heavy snowfalls might occur over large areas of Canada, Siberia, Greenland and the mountains of Scandinavia. Much of this snow might last through the summer. Fogs and increased cloudiness due to an ice free summer Arctic Ocean would also inhibit snow melt. All it takes a few successive years where some snow cover survives the summer to establish a basis for continental glaciation. As perennial snow cover increases, temperatures fall due to refection of solar radiation back into space (increased albedo effect).

Whether this process can produce a new glacial advance depends on the rapidity of global warming. If warming is rapid and intense, it will overcome these mechanisms and we will roast. If global warming is less intense, we may have another round of continental glaciation and we will freeze. Comments?

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Technology / Using drilling technology to generate electricity

« on: 25/08/2008 20:35:46 »

The earth is a ball of molten material with a thin solid crust. It seems we would drill to depths where water boils and harvest this vast energy resource rather relying on a few active geothermal locations. The system could also take advantage of the force of water dropping down a 10km deep hole. The resulting steam could run generators provided the steam conduits are sufficiently insulated against heat loss. The water could then be recaptured and recycled. Mother earth does all the work through gravity and thermal energy.

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Physics, Astronomy & Cosmology / How can an electron travel "all possible" paths from emitter to receiver?

« on: 25/08/2008 00:46:07 »

QM says an electron takes "all possible paths"(Feynman)from emitter to detector. What does that mean? Clearly some paths are much longer than other paths. If the electron is traveling as wave, I can see how it would "spread out" in space. I assume the electron "collapses" to a particle when the wave front reaches the detector, but what about the rest of the wave that is spread out in space? Does it just disappear? How does the wave "know" that a tiny part of its wave front intersected a detector? What if there were more than one detector, each precisely equidistant from the emitter? Does the wave "choose" where to collapse. Can it collapse at two or more places at once? 

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Physics, Astronomy & Cosmology / does validity of SR depend on definitions of randomness/information?

« on: 16/08/2008 23:02:29 »

Given that faster-than-light action at a distance has been established experimentally (Aspect and others), SR has been defended by holding that what passes between two parts of a split photon is not information and that non-local effects are "random".
Just what definitions of these terms are being applied? Probably the best definition of "randomness" was given by Kolmogorov paraphrased as follows: Given a character  sting in some descriptive language of length λ, that string is random if and only if there exists no algorithm which can generate that string other algorithms longer than λ. Information content has been defined by Shannon as I(E)= -c log(P(E)) where E is an event, P is a probability, c is a positive constant and the log is usually taken to be base 2. Have these (or similar)definitions been applied to this issue? It would seem to me that "action" that is random is no action at all.