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D H

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Everything posted by D H

  1. You have not provided an explanation. An explanation at a minimum must match what we already know about reality (postdictions) and preferably tells us something new (predictions). This makes no sense. A clue to what? That clue is evidence. On the other hand, if someone makes an unsupported and unsupportable claim in court, judges can not only throw said claim out, they can throw the claimant in jail for contempt of court.
  2. Although the distinction between scientific theory and scientific law is a bit fuzzy, it is generally the other way around, Mokele. Laws are very simple, empirical, and final statements. Theories are deeper and a bit more malleable than are laws. An example is black body radiation. In 1896 Wilhelm Wien developed an empirical rule to describe the high frequency spectrum of thermal radiation, Wein's Law for black body radiation: [math]I(\nu,T)=\frac {2h\nu^3}{c^2}e^{-\,\frac {h\nu}{kT}}[/math] A few years later, Max Planck noticed that a very simple correction to Wein's Law enables a match to the full spectrum of a black body radiator: [math]I(\nu,T)=\frac {2h\nu^3}{c^2}\frac 1 {e^{\frac {h\nu}{kT}}-1}[/math] This is Planck's law, still a completely empirical law at the time it was published. Note well: This is not the Wein-Planck Law. Scientific laws are final. Suppose instead that Wein had developed a theory behind his equation and Planck made a minor correction to that theory. The modified theory would be called the Wein-Planck theory. The theory of black body radiation was not developed until several more years had passed. The theory explains why Planck's law is indeed correct.
  3. In that, case, you engaging in purely speculative behavior. There is nothing wrong with that per se. However, we have a place for speculations. Thread moved to the speculations section.
  4. Epiménides, as it stands, your "theory" is little different from fairy dust. It has no substance. One more time, it is not our responsibility to come up with ways to reject your non-hypothesis. It is your responsibility to bolster your non-hypothesis to the stage of a true hypothesis. Your persistent use of invalid logical arguments does not satisfy this responsibility.
  5. gre, If you mean that the fundamental forces are carried by particles, then the answer is yes. That is exactly what quantum mechanics dictates. The carriers of the fundamental forces are the gauge bosons. If on the other hand you mean that "force" itself is quantized, that is a far different question. You are essentially implying that photons come only in discrete set of frequencies. There is no evidence of this (yet).
  6. Science uses logic, but that doesn't mean science is logic. Science also abuses logic. In particular, the cornerstone of science, "proof" by experimentation, is not logically valid. Scientists of course know this. That is why scientific theories are deemed to be at best provisionally correct.
  7. You're on the right track, but forces are the subject of Newton's second law, not the first. The first law talks about the behavior of a particle that is not subject to a force. Newton's first two laws are in part definitional and in part axiomatic. The axioms of Newton's first two laws: Space and time are something distinct in and of themselves. There is an absolute time that "flows equably without regard to anything external." We can only measure relative time (duration) rather than absolute time. There is an absolute space that "remains always similar and immovable." That this absolute space is Cartesian is, I think, implicit in Newton's concept. (Non-Euclidean geometries were not perceived as valid for more 100 years or so after Newton's time.) Just as we can only measure relative time, we can only measure relative time, we can only measure relative space (displacement) rather than absolute space. In three dimensions, the relative displacement from some arbitrary point is a relative reference frame. There are things called forces that affect the motion of an object. Objects are endowed with mass, an absolute location, absolute motion, and absolute momentum. The absolute momentum of a constant mass object is the product of its mass and absolute motion. Newton's first law: The absolute momentum of an object that is not subject to any forces is constant. It is possible to find a relative reference frame (herein called an inertial reference frame) and a relative time such that the relative momentum of an object that is not subject to any forces is constant. Newton's second law: The time derivative of an object's absolute momentum is proportional to the net force acting on an object, with the constant of proportionality being the same for all objects. Principle of superposition: The net force on an object is the vectorial sum of the individual forces acting on the object. (These are not Newton's words. Newton predates the concept of a vector by 200 years. Newton used geometric arguments.) Note that the first law only talks about what happens in the absence of forces. It does not describe what a force is, or how a force, if present, affects the motion of an object. That one can find an inertial reference frame is axiomatic. However, the last axiom can also be seen as definitional of a relative inertial reference frame. Newton's second law, coupled with the superposition principle (which David Hestenes calls Newton's fourth law) can be viewed as defining what constitutes a force.
  8. General relativity is a classical (non-quantum) theory. Physicists have not yet been able to reconcile general relativity and quantum mechanics. The bolded statement (bolding mine) is critical. Other than some gross characterizations (gravitons must be massless and have spin 2), physicists do not have a good model of what gravitons are and how they mediate gravity. That is not to say that such a reconciliation is not achievable, just that it hasn't been achieved yet.
  9. Resha, could you clarify the issue you are trying to raise? I see several possibilities: Are you talking about two inherently untestable theses? In this case, who cares? IMHO, both are absolutely worthless philosophical rambling. (Now ask me what I really think.) Are you talking about two different theses that predict different outcomes for the same experiment which hasn't been performed? Here the jury is out. Neither can be deemed better (or valid) until some experiment is performed. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A sometimes but with thesis B other times? Here the jury might still be out. An experiment that yields different results at different times is not a good experiment. The experiment itself might be in need of an update. If the experimental results are indeed valid, I would venture that both theses have been falsified. Are you talking about two different theses that predict different outcomes for the same experiment, and the experiment agrees with thesis A always? This one is easy: The thesis that matches reality wins, regardless of how "ugly" it is. Are you talking about two different theses that predict the same outcome for all experiments? Here "beauty" does come into play. This is why special relativity is taught rather than Lorentz ether theory, even though the two are indistinguishable in terms of predicted outcomes. Are you talking about something else entirely?
  10. That is word salad. What problems are present in the "accepted theory" regarding the speed of light? Yes, I did. I'll answer again: You are asking an invalid question. When scientists do compare hypotheses, it is in the sense of developing experiments to distinguish the hypotheses and evaluating the results of the experiments to determine which hypothesis best predicts the observed results. This of course can only be done if both hypotheses are predictive. You do not have a hypothesis yet because as it stands your conjecture has no predictive powers. It is not our job to flesh out your conjecture. That burden falls upon you.
  11. No. You can't just make up a formula and expect it to be valid. You are implicitly assuming that the Earth's magnetic field strength varies with the square or inverse square of the radial distance. Not sure which you are implying here; you don't even have an equation (i.e., something of the form y=f(x)). What makes you think this would be valid? (Hint: It isn't). To zeroth order, the Earth's magnetic field intensity beyond the Earth's surface is proportional to the inverse cube of radius. Moreover, the Earth's magnetic field away from the Earth's surface has a lot of high-order moments. To get a picture of what goes on inside the Earth you will need to study magnetohydrodynamics.
  12. Until you can come up with a test of your conjecture, you don't have a "theory". You have what is called colloquially a wild-ass guess. That is not how science works. The test of a scientific hypothesis is how it fares against reality. The standard model of physics has been tested against reality, and so far has passed all such tests. This is not to say some future test (e.g. LHC) won't find a flaw in the standard model. Many physicists hope that it will. You conjecture (and its a stretch to call it a conjecture) has no meat. Develop some mathematics and develop some predictions. Until you do so all you have is vague philosophical ramblings.
  13. If the pole were made of some unstretchable, incompressible, unbreakable, and unbendable material (unobtanium in short), the Earth would undergo significant harm, but nothing much of interest would happens to this pole. Suppose, on the other hand, the pole is a thin, malleable wire. This, I think, is closer to what the OP is referring than the rigid unobtanium rod. What is going to make the wire wrap itself around the Earth? There are a lot of different cases to study here. I'll pick a few. Suppose the wire pops into existence as a perfectly straight wire with a north-south orientation, justing touching the Earth at the equator, and zero inertial velocity with respect to the center of the Earth. Ignoring atmospheric effects, the wire will quickly hit a snag on the Earth (Mount Chimborazo, for instance). The middle of the wire will now be moving at 1674 km/hr. That will put a lot of tension on the wire. Even if the wire doesn't break, it certainly won't form a great circle. The wire start forming a horseshoe shape curving off to the west from the contact point. with a north-south orientation, justing touching the Earth at the equator, and an inertial velocity 1674 km/hr due east (at the contact point). with respect to the center of the Earth. A point on the wire away from the contact point will be moving faster than the corresponding point on the Earth directly underneath the point in question. The wire start forming a horseshoe shape curving off to the east from the contact point. with an east-west orientation, justing touching the Earth at the equator. Again the velocity of the wire will effect the outcome. If the wire has zero inertial velocity, it will double up on itself once it hits a snag. There will be some doubling-up even if the wire is moving 1674 km/hr due east. The wire above the earth is a bit more interesting. A rhetorical question: What is going to make the wire wrap itself into a circle, as opposed to simply falling to the Earth? Answer: Nothing. Suppose instead of an initially straight wire we have a very large spool of wire in a circular orbit around the Earth. We'll connect one end of the wire to a vehicle with thrusters. We'll use some kind of forced motion to make this vehicle move a tiny bit faster (or slower) than orbital velocity (but stay along the orbital path) and unspool the wire. Eventually our vehicle will rejoin the spool. At this point in time, we'll splice the free end of the wire to the wire coming out of the spool. Voila! We have a wire circling the Earth! The wire won't come crashing to Earth -- immediately, that is. The ring is unstable. See http://eprints.gla.ac.uk/38/01/JIBS_C_McInnes_56_308.pdf for example.
  14. D H

    zero G

    In what sense? The Earth is perpetually accelerating sunward due to gravity, impeded only by an immeasurably small drag against the interplanetary medium. Freefall. There are at least a couple of misunderstandings here. (1) The perpendicular velocity does not counter the pull of gravity. That pull is always there. (2) Weightlessness (the feeling of weightlessness) results whenever the acceleration of some body is (nearly) equal to the acceleration induced by gravity. This condition is the norm in outer space but can also be forced (e.g., the Vomit Comet and some amusement park rides). The Sun raises tides. While we can't feel tides in our body (too small), they do exist, and Sun-induced tides can be seen in larger bodies of water.
  15. The rubber sheet analogy is just that: An analogy. It is important to keep in mind that *all* analogies fail in some sense. The visual explanation from the rubber sheet is imperfect. (Can you see four dimensions?) Compounding this imperfect explanation, you are looking at the analogy incorrectly. The analogy isn't describing up and down. The crux of your misunderstanding is in this statement: "The Object warps the space time fabric in one Direction and that's it." The rubber sheet analogy warps portrays warping of the space time fabric in two dimensions -- the two dimensions on (not normal to) the rubber sheet. Where the rubber sheet analogy goes wrong is that it gives the impression that there is some other dimension involved. You have carried this misrepresentation even further, taking that out of plane stretching to be the only warping of space time that is occurring on the rubber sheet. The think to look at is the grid lines on the rubber sheet, not how far the sheet is been stretched from the flat plane.
  16. I meant deduction, the importance of which Popper ignored. Popper instead focused on empirical theories ("all swans are white") -- naive induction. In a sense, his example "all swans are white" parodies the scientific method. It is a straw man. Consider special relativity, for example. Einstein started from the basis of two simple axioms -- two universal quantifiers. The Lorentz contraction is one of several consequences or deductions from these axioms. Lorentz on the other hand postulated the Lorentz contraction in what is now called Lorentz ether theory. How to distinguish the two (special relativity and Lorentz ether theory)? Observationally, you cannot. The distinction is in the nature of the axioms. Popper's analyses would have been closer to the mark if scientific theories were purely empirical. Our best scientific theories are far from empirical. Scientists have discarded Lorentz ether theory because it is too empirical. Scientific theories (at least the most powerful ones) involve universal quantifiers. "The speed of light is the same for all observers." There is no gray there. The power of the theory springs in part from the universality of the quantifier. Using a probabilistic approach is going to limit you to empirical theories, theories with little consequence. "All swans are white" has no consequences of note. It is not a good example of a scientific theory. Another big problem with a probabilistic approach is Hempel's paradox. "All swans are white" is logically equivalent to "all non-white things are non-swans". In a Bayesian sense, observing a green apple or a brown cow is confirming evidence of the proposition that all swans are white. This discussion of error correction is a bit off-topic. For one thing, the problem of induction was known long before Popper and long before Shannon. Even more importantly, how does looking at the scientific method from the perspective of communication channels add to the discussion? That is part of what I am saying. Popper focused on a fictitious empirical law. He created a straw man.
  17. The difference between me (a potzer) and an expert is the expert's ability to see patterns without computation. They have an amazing ability to capture the gestalt of chess game in a glance. That is why experts can play dozens of games simultaneously. An article: http://gestalttheory.net/archive/arncomp.html. That is why you (and I) are "awful chess players". Your chess thinking is too much like that of a dumb computer chess program. You (and I) are further hindered by not being able to think that way very well. How many moves ahead can you see? Computer chess programs now have nine or ten (maybe higher?) move lookahead. Lookahead is brute force. That link is a bibliography to a slew of articles on the no-free-lunch theorems. In essence, there is no "best" machine learning algorithm. Given any two machine learning algorithms, there will always be some cases where algorithm A outperforms than algorithm B and other cases where algorithm B outperforms algorithm A -- including algorithm B being pure random pulling junk out of a hat. One way out of the morass is self-awareness. We are able to pick and choose strategies -- which implies we have least a second-order logic. First off, the brain is more than neurons. There are glial cells after all that we *know* are associated with learning, and maybe even other agents that we do not yet have nailed down (particularly long-term memory). Secondly, there are many researchers in the field of artificial neural nets who claim that neural nets are more than Turing machines.
  18. No. Induction underpins all of science. Scientific theories cannot be proven true. The mass of evidence in support of some theory is not proof of correctness in a logical sense; to think that it does is to commit the logical fallacy of affirming the consequent, "If P then Q; Q; therefore P". What experimental evidence can do is annihilate a scientific theory; "If P, then Q; ¬Q; therefore ¬P" is the logical valid concept of denying the consequent, or modus tollens. One lousy piece of contradictory evidence can throw a hypothesis (or even a long-standing scientific theory) into the dustbin of falsified conjectures. Observing thousands of white swans, but never seeing a black swan, does not logically prove the hypothesis "all swans are white". Popper, IMHO, is simply wrong regarding his objection to induction. He ignores the importance of deduction in the scientific process. From the onset, an ad-hoc hypothesis has significantly less merit than does a hypothesis with a solid logical underpinning. Scientific theories are "proven" in a manner similar to convictions in law. A legal conviction requires a logical rationale in the form of motive and opportunity, lack of exculpatory evidence, and sufficient confirming evidence. Similarly, a scientific theory requires a solid logical underpinning, no disconfirming evidence, and sufficient confirming evidence. Popper is right in the concept of falsification. Because of the problem of affirming the consequent, legal convictions can be overturned and scientific theories can be discarded in light of new exculpatory or disconfirming evidence. It is a critique of the concept of naive induction, which is in itself a logical fallacy. Popper posed naive induction as a straw man of the scientific method. Scientists don't just make observations willy-nilly. Their observations are guided by extant or proposed scientific theories. Scientific theories, particularly the paradigm-shifting theories, typically do not arise as a an ad-hoc explanation of disparate observations. An example: Noether's first theorem (http://arxiv.org/abs/physics/0503066). The conservation laws and Lagrangian formulation of physics were well-known and well-confirmed at the time Emmy Noether proposed her theory. She didn't need any new observations to tie the conservation laws to symmetry. Through some creative leap she tied the work of Lie, Hamilton, and Lagrange to formulate a new and extremely powerful theorem (not theory). The process of forming a new scientific theory is inherently creative. It is, IMHO, something outside the realm of lower-level logic and Turing machines.
  19. There is a bit of a trick to this problem. The problem statement explicitly describes two trips: One in which the speed is 15 km/h faster, reducing the trip time by one hour and the second in which the speed is 10 km/h slower, increasing the trip time by one hour. The trick: there is an implicit third trip. Those speeds and times refer to some baseline trip. Call the speed and time on this trip v and t respectively. The distance for this baseline trip is d=v*t. The two stated trips cover this exact same distance, but with speeds and times that differ from the baseline. Can you take it from here or do you need more help?
  20. Superior in playing chess, yes. Superior, in general, no. That isn't intelligence. It's just dumb brute force. A chess playing computer program is no more aware of what it is doing than is a Jacquard Loom. I strongly disagree. I'm not alone in this regard. Penrose, Searle, Gödel, and a host of others are of the same opinion. The no-free-lunch theorems get in the way of a non-self-aware AI achieving strong AI. Magic is not required to say that our minds are only Turing machines.
  21. While computers have surpassed humans in playing chess, they have not done so by means of anything one could connote as "intelligence". They have surpassed us by dint of pure dumb brute force. I am a holdout that we humans are something more than Turing machines.
  22. You are not alone in that opinion. That is essentially what the no free lunch theorems say. To say that the theory generation process is mechanizable is to say that there is a free lunch in the scientific method. I disagree. So, apparently does Einstein ("I never came upon any of my discoveries through the process of rational thinking.").
  23. Just because you don't like it doesn't mean it is not the way things are. And that is why it's not a theory. Theories HAVE to be falsifiable. Quantum mechanics certainly is, and no ones managed it yet... Excellent point, Klaynos. A scientist should play devil's advocate in at least two ways. First and foremost, they must ask "how could I prove my hypothesis to be false?" Secondly, they must ask "does my hypothesis add any value to the body of science?" One way to answer both is to identify an experiment whose results will conflict with either the new hypothesis or with extant theories. So, Epiménides, what observations does your "theory" indicate will occur that conflict with predictions based on the standard body of physics.
  24. This is exactly why I brought up the no free lunch theorems in that other thread on philosophy of science. To say that there is a mechanical method for generating theorems implies, in my mind, that there is such a thing as a free lunch.
  25. D H

    Annoyed

    Whoa! This raises more alarm bells to me than anything else you have said, "Tom". Using your flat mate's account is one thing. Using his name as your own is quite another.
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