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DrRocket

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Everything posted by DrRocket

  1. First, re the thread title. No, evolution is not provable. Neither is any other scientific theory. "Proof" applies to mathematics, not to science. Acceptance of a scientific theory is always provisional, and is based on evidence, not proof. There is certainly evidence in support of evolution. Genetics is a fairly well-developed discipline with roots in the chemistry of the DNA molecule and lots of supporting data at all levels from molecular to cellular to large-scale breeding. Genetics is an essential ingredient of evolution. Fossil evidence clearly shows a progressive differentiation of species. You can explain that via natural selection, or via repeated interventions of the supernatural. If you accept repeated interventions of the supernatural, then ALL science, not just evolutionary biology, but also chemistry and physics, anything based on an orderly and predictable nature, must be set aside. That is not reasonable. Evolution is not, yet, a quantitatively predictive theory, but it is the best and most reasonable explanation of that which has been observed. It is certainly supported by a preponderance of the evidence. That is not proof. It is as close to proof as you will find. Evolution is distinct from abiogenesis. While abiogenesis very likely did occur on Earth, that is not certain. Perhaps seeds of life arrived on a meteorite. No one really knows. There is no solid theory for abiogenesis. The evidence is basically that we are here now, and it is highly unlikely that life existed 10^-33 sec after the big bang. On a big picture level that is pretty good evidence. The most common misconception of the creationist wackos is that science and religion are incompatible. They are not. Science is incompatible with superstition. If you insists that the Earth was created in 7 literal days, then you are doomed to wallow in superstition. If you are willing to believe that a higher power acts in the natural world via natural processes then there is no conflict. If you insist that a higher power act as you dictate that such a power act then I suggest that you place yourself in the role of an even higher power, and that is just a wee bit arrogant. The Bible is not a physics book, a chemistry book or a biology text. Neither is the Torah, the Koran, ... This is not to suggest that science supports religion either. It is completely independent. Creationists also fail to understand this point.
  2. So far as I know an inner derivation is one that arises, as you describe frrom the commutator of some element in the algebra (or the adjoint representation in the case of Lie algebras, but I assume we are talking about associative algebras here). I presume that an outer derivation is a derivation that is not inner, but have not seen the term defined. That said, I do not have answer to your question. Maybe this paper could serve as a place to start looking, but I must admit to finding it outside of my interests and have not read it in any detail. The question as stated is purely algebraic. Is there some motivation in analysis or geometry, or perhaps a more restrictive setting ? In settings with which I am more familiar derivations arise naturally, and one is not usually seeking just an arbitrary abstract derivation, but rather implications of the specific derivation or class of derivations that has presented itself (as in the identification with the tangent space at a point as the derivations on the germs of smooth functions).
  3. DrRocket

    Current Flow

    The energy transferred in an electric comes from the electromagnetic field, not the kinetic energy of the electrons. Now think about a long pipe narrow filled with pping-pong balls. Push on a ball at one end. Another ball pops out at the other end almost instantaneously, despite the fact that the individual balls move slowly and not very far.
  4. An atomic clock registers the proper time of its world line. You need to learn some physics and stop making positive assertions that you don't understand. Making up physics as you go along is just silly. "The state of the space in which it exists" is meaningless unless you can define your terms in detail, and specify precisely and quantitatively what constitutes your state space.
  5. This would be a much stronger argument if it were true. http://en.wikipedia....i/Vacuum_energy It actually takes some fancy footwork to avoid predicting that the vacuum energy is not infinite. As it sits now the prediction exceeds observation by a ludicrous factor. Nobody knows why. The discrepancy between the vacuum energy predicted by quantum electrodynamics and the cosmological constant that is consistent with the accelerated expansion of the universe is regarded by some (Wilczek for instance) as the most important and perplexing open problem in quantum field theory.
  6. But the REAL no. 1 is the greatest and without flaw -- just ask him. Yes, thanks to Witten, string theory has become a terrific conjecture machine, particularly for algebraic geometers. That is of sufficient value to merit a Fields Medal. Someday somebody may even be able to define what string theory is.
  7. This not a mechanistic answer, so may not satisfy you. Solid propellants, like flash powder, gun propellants and solid rocket fuels are normallly modeled empirically using the burn rate equation: [math]R = cP^n[/math] where [math] R[/math] is linear burn rate, [math] c [/math] is a constant [math]P[/math] is pressure and [math]n[/math] is known as the "pressure exponent" or just "exponent". This equation is approximate, no more, and the "constants" are only approximately constant over a limited regime. In particular, when burn rate vs pressure is plotted on a log-log scale to deternime the exponent, the curve sometimes kinks exhibiting what is called a "slope break". Now, the combustion is stable when n<1, but when n>1 pressure, and burn rate, increase unstably. Gun powders, for instance typically have exponents >1 and pressure s limited by the very short time involved. Rocket propellants have a slope of, say 0.6, and burn stably. Your flash powder probably has a high exponent. One possibility with "blue aluminum" is an oxide coat on the particles that breaks under high pressure, and likely under high dP/dt, exposing more actual fuel to the oxidizer. This is purely speculative since I don't know what "blue aluminum" is. I do know that the morphology of aluminum particles has a significant effect on burn rate. Before using that stuff, some closed bomb combustion tests on small amounts of mixed flash powder would be in order. Also in order would be the standard impact, ABL friction and ESD sensitivity tests. KIDS: DO NOT TRY THIS AT HOME. This is dangeerous stuff. Professionals only. This web site is supposed to be the source for information on blue aluminum. I found some discussion in the forum, but little "meat". My impression from the video was of a group with little safety discipline.
  8. Any ideal, accurate clock -- atomic, light, pendulm, whatever -- under any condition-- speed, gravitational field, whatever -- ALWAYS ticks at the rate of one second per second. Always. Relativity, particularly general rrelativity, tells us that time is neither universal nor absolute. An accurate clock reliably measures the proper time of its world line. Different clocks, subject to different conditions -- relative speeds, gravitational fields, etc, -- have different world lines and therefore register differences in proper time. Time is not some universal quantity, but is a characteristic of a time-like world line joining two points in spacetime. In general relativity it only makes sense to compare two clocks at two points of intersection of their world lines. There is no exact comparison of "time here" with "time there" -- as is allowable in special relativity. Special relativity is only a local approximation (on the tangent space) to the more exact general theory. Clocks do not "tick slower" in a gravitational field. That makes no sense. Speed of something is [math] \dfrac{change \ in \ something}{change \ in \ time}[/math]. And [math] \dfrac {change \ in\ time}{change \ in \ time} = 1[/math]. Always. Confusion arises when Newtonian intuition and Newtonian concepts, like the "flowing river of time" are carried over and inserted naively into a relativistic setting. "Coordinate time" is mistaken for proper time. Clocks measure proper time and nothing but proper time. Proper time is invariant. Coordinate time is not. Ordinary velocity is not invariant. 4-velocity is invariant. Ordinary energy and momentum depend on a choice of coordinates (reference frame). The momentum-energy 4-vector is invariant. If you are going to understand relativity you must invest the time to understand the mathematics in which it is formulated. You cannot even accurately describe the concepts involved in general relativity without using the mathematics of Riemannian geometry (pseudo-Riemannian geometry to be pedantic). This stuff is not intuitive, and if let your intuition be your only guide, you will certainly go astray.
  9. DrRocket

    Hate

    The reaction is a function of one's moral character. That strategy could also result in someone who thinks for himself, who would otherwise be indifferent, stepping in to protect the bullied from the bully.
  10. Mathematics is not rigid. Mathematics is the study of order, any order that the human mind can recognize. When mathematics is not adequate for the study of some orderly phenomena, we invent and develop new mathematics. Even apparent disorder can be studied, as with the theory of probability and chaotic topological dynamics.
  11. You do, of course, realize that this is complete gibberish, don't you ?
  12. The real problem in trying to educate you is that you think the above juxtaposition of nonsense words constitutes a cogent argument. There is nothing to debate or correct. It doesn't mean anything. You refuse to learn physics, even the basic concepts and the meaning of specific well-defined technical terms. As a result you babble. It is the height of arrogance to think that you can understand a scientific discipline, let alone criticize and improve upon it, without studying it enough to know the basic content. Read a physics book.
  13. The balloon analogy is an ANALOGY. It is a (poor) substitute for the actual model from general relativity, which is a space-like slice of an intrinsic 4-dimensional Lorentzian manifold, most often assumed to be homogeneous and isotropic. The fact that you don't understand the preceding sentence is why popularizations use analogies. You are trying to extend the analogy to a real model. That won't work. Real models are constrained by general relativity. Analogies are not supposed to be valid. They are ANALOGIES. In the case of the "thick-skinned balloon" it is not even clear what you mean by an analogy. It sounds more like a model. How that "explains" expansion or the size of the universe is a complete mystery. The observable universe is a 3- ball, centered on the observer. There is no debate on that. The topology of the entire universe is unknown. You should consider reading Alan Guth's The Inflationary Universe. It will not resolve all of your problems, but it will give you an idea of the nature of the real questions.
  14. This is just wrong. You have completely misunderstood the balloon analogy, which is quite common. It creates as much confusion as enlightenment. The balloon is used to illustrate the idea of a manifold, without actually using the necessary mathematics. The idea is that the surface of a balloon is locally just like the usual plane -- the surface of a balloon is a 2-manifold. The problem lies in visualizing the balloon as embedded in 3-space. To make the analogy useful you have to forget about the balloon as being in 3-space and imagine that the surface of the balloon is all that exists. Then there is no "center" of that surface. The universe is likewise an "intrinsic manifold". It is not embedded in anything larger. If it were, that something larger would be the universe. The universe is, by definition, the whole enchilada.
  15. I'm not eve sure what "index of refraction" means when applied to a handful of atoms.
  16. The universe appears to be homogeneous on the largest scales, so mass is uniformly distributed, and there is no "center of mass". A manifold is a topological space that is locally Euclidean -- locally just like ordinary space. The surface of a balloon, or of a globe is a 2-dimensional manifold, in this case a 2-sphere. An intrinsic manifold is a manifold that is not explicitly embedded in anything larger. Isotropic means essentially "the same in every direction". You can talk of the center of the solar system, of the galaxy and of the local group, and you can continue as you expand to any number of subsequent steps, but that does not get you to a center of the universe. If you started with a point on the surface of a balloon and expanded in concentric circles you would always find the center to be the point that you started with. But the surface of a balloon is homogeneous and no point is distinguished from any other.
  17. I am going to make a wild guess and assume that the professional interrogators in the military and in intelligence agencies are aware of any effective drugs of which you are knowledgeable. Maybe even a couple more.
  18. emf is not a current, induced or otherwise. emf can cause a current to flow under the proper conditions, but it is not itself a current. It is essentially a synonym for "voltage". A voltage source will cause a current to flow, consistent with the generalized form of Ohm's law (impedance vs pure resistance) but voltage is not current. The terminology is most commonly used in conjunction with Faraday's law in the case of time-varying magnetic fields and magnetic induction, in which case the integral of the E-field around a closed loop is not 0, and in fact is the "emf" in the loop. That is how ordinary electrical generators work. On the other hand, it is not a force either. Any or all of those books should be readily available through interlibrary loan. They are very widely used.
  19. "electromotive force" is somewhat unfortunate terminology. It is not a force. It is a line integral of the E-field. The units of the E-field are volts/meter which when integrated over a path (distance) yields volts. Force on a charged particle comes from the Lorentz force equation: F=q(E + v X B)
  20. Apparently you do not understand the nature of an ad hominem argument. Ad hominem argument : "You are stupid, therefore your argument is fallacious." Unnecessary insult: "Your argument is silly, and shows that you are stupid." Valid, helpful observation:"Your argument contains several misconceptions and mis-statements of fact that demonstrate that you are ignorant of the subject matter. Please read a physics book."
  21. Oh fer crissake. Try ANY book with a nane like "Advanced Calculus" for the rudiments of line integtrals. Kaplan's book would do. Calculus on Manifolds by Mike Spivak is one of the best with a more modern flavor. For thetheory of classical electrodynamics, Classical Electrodynamics by J.D, Jackson is the standard. Equally good is Electrodynamics of Continuous Media by Landau and Lifshitz. Somewhat easier books are Introduction to Electrodynamics by Griffiths and Classical Electromagnetic Radiation by Marion. The Feynman Lectures on Physics covers electrodynamics at an introductory level, and many other topics as well. This is stuff that is so well-known and standard that references ought not be necessary. If you are tryiong to confirm that you have no idea what you are talking about, then you are doing a bang-up job. Go read a physics book. There is no such thing as "charge intensity". There is a magnitude to the electric field and there is "charge density". Voltage is not force, is is somewhat analogous to a pressure difference, but voltage is strictly speaking only a valid concept in the static case in which the e-field is conservative. Your "understanding' is sadly deficient. Go read a physics book.
  22. In case no one noticed that "paper" in the archives has a long list of revisions and no history of submission to any peer-reviewed journal. That, combined with the incomprehensibility of the text itself, is a big hint.
  23. The similarity is more imagined than real. You can integrate any vector field over a line. The (classical Newtonian) gravitational field is conservative. The electric field is only conservative in the non-time-varying case. Unless the field is conservative the value of the line integral depends on the whole path and not just the end points. When a vector field is non-conservative it is not derivable as the gradient of a scalar field (aka potential function). In the time varying case "voltage" is not well-defined. lemur is in desperate need of some time with a physics book. There is no effective substitute.
  24. No, it is not. It is gibberish. Incoherent babbling. Read the book. Newton "stood on the shoulders of giants". Einstein built on the mathematics of Riemann. No one has ever understood physics without reading the work of those that came before them. Newton was not smart enough. Einstein was not smart enough. You aren't either.
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