decraig

hey, homes.

Yes it does. But we're quibbling n getting no where. For a single quanta radial symmetry is broken upon the measurement you invoke. However you think trajectory has objective existence before measurement. OK, but now you can't explain interference objectively without invoking Bohmian pilot waves. Quantum mechanics is a mess of senselessness. We can just leave quantum mechanics as a theory in search of "making sense". Nobody else really cares who wins this butting contest between you and me. I was just looking for ideas. Truce? Unless you happen to have some special insight outside the mainstream philosophizing....

??? Yes.... The examples I gave explaining why a theory works, rather than asking why. But I think I know what you mean. Do sr and gr compliment each other? I don't know what that means, except we can expect to good accuracy that space is mostly flat for most experimental outcomes. My opinion is different: one is better than another at generalizing what nature is. We differ wildly in our points of view in this regard. I think using a former theory degrades what is subsequently developed using this theory, such as qed conducted on the background of special relativity. As you might recall, Einstein developed a theory of gravity by taking Newtonian inertial-gravitational mass equivalence to the next step: "why are they equivalent?," giving rise to the EEP. Per your second paragraph, I do play similar games with quantum, and classical mechanics (where I assume you mean relativistic theory is to be categorized as classical). Now, I don't recall making any headway asking why quantum mechanics works. The direct approach seems hopeless. I do ask why relativity theory should be formulated as it is. It's evolved, for the most part, on the adaption of vector bundles to tensor bundles. I reject this (mostly) and advance alternate formulation of my own. In so doing I've found an unexpected parallel in gr to wave-particle duality. My 'why' questions or demands for explanation are a little more abstract, such as: why are the formulations of gr so goofy? I think we who wish for better theory always, always ask why. It doesn't matter what others say who will tell us we can't ask why questions of physics. Those who are not interested in this, don't ask why, but are interested in becoming proficient in accepted theory. These are two different species.

Ok, I see. [math]c^4m^2=E^2-p^2c^2[/math] and radial symmetry implies [math]p=0[/math], implies [math] m = +/- E/c^2[/math]

I think so, at least in one manner. The force between charged particles could be seen as action at a distance. But by positing electric fields we can now say charge acts to create fields, and fields act on charge. Relativity theory explains Newton's gravitational action at a distance as the weak field vacuum solution where matter shapes spacetime and spacetime acts back on matter. One theory can "explain" another theory. But its and endless task, as the superseding theory demands explaining as well. It's turtles all the way down. So I don't think it's such a bad idea to wonder how to explain a theory.

Ok. It sounds a bit award to accelerate. Do lead with the powered or unpowered skate?

"The Universe shouldn't expand infinitely?" Probably not, though it seems to be expanding indefinitely. Any why not? Current spacetime theory embodies transfinite quantites. Relativity theory is written in differential geometry. An order change in transfinite values should be well accommodated, without modification to general relativity.

Quantum mechanics makes no sense. This is obvious. So where does this lead? I examine the particle interpretation. -------------------------------------------------------------------------------------------------------------- Evolution of quantum states do not admit particles outside of the Bohmian mechanics interpretation where particles still require "pilot waves" to guide them. Pilot waves are a field. These waves disappear or no longer interact with matter. This is a lot of metaphysical baggage that strays far from "making sense" so I will no further consider the Bohmian interpretation. The evidence for particle nature seems to be: 1) Charge is measured in discrete units. 2) Part of a particle is not measured in one place, and another part somewhere else. 3) Energy absorption is not spread all over, but localized. See the photoelectric effect. There must be a few more I can't think of right away. With the exception of the photoelectric effect, the way experimental physicists usually determine quantum effects is through measuring position. A good example is the Stern-Gerlach experiment where the state of spin angular momentum of an atom is implied by measuring the location where energy is absorbed. I don't see any of this as implying particle nature to matter, but rather the quantization of various physical quantities. But I could be very dim witted about this. I'm fairly sure, for instance, that one wouldn't measure a spin flip in one place and an increase in energy in another, though I'm not aware of any experiments that demonstrate this. (Any reference, anyone?) In fact, I'm not at all very sure what you-all mean by "particle" other than something that has spatially point-like existence having various physical quantities associated with this point. -------------------------------------------------------------------------------------------------------------------------------- How do you measure a particle? You hit it with another particle. Consider an alternative: For various measurable quantities, interaction of one field with another obtains descrete measurments. But this is not quit enough consideration; we have to account for energy, spin, and charge all at once. This amounts to some sort of insistence that these quantities are intimately related for a particular field (particle) and inseperable. In effect, demanding inseparability echos the classifications of particle physicists. ---------------------------------------------------------------------------------------------------------------------------------- The mystery for me is that measurements are descrete. Secondly, why are these descretes lumped together one way or another, depending upon the species of particle involved, and nothing in between?; there is not a continuous spectrum of mass. I think some of these answers might be deferred in demanding gauge invariance and extemal action. referring to my potential dimwittedness, and more, did i miss something anywhere?

A "Perpetual Motion Machine" is device where we can get useful energy from random energy, or from no energy at all. No one has found anything like this. Many have tried; just as many have failed. I've spent more than than a few hour watching YouTube videos about perpetual motion machines hoping for the long shot, to see something I shouldn't see. I've watched videos of the uninformed, the hopeful, magnet fanatics, frauds and magicians, and grades in between. Nothing. Some think the laws of thermodynamics are God incarnate; but they are no more than a human construct, as is all of physics. Physics is not discovered, it's invented. If there are better laws of thermodynamics than available in your undergrad text, they will obtain from decoherence theory, in my view. This concerns the quantum mechanical nature of things. And just maybe, there will be a loop-hole. Or just maybe, relativity theory will supply it; global energy is not well defined. But it won't come from playing with magnets, or hydrogen generators that I can see. (On this planet hydrogen is an energy storage media, not an energy source. And this goes for the parasites who look for deuterium and tritium fusion at our expense.) How much oil does a foundry take to purify your "eco-friendly" solar cells? How much coal for the battery pack on a Prius? How much spin-up cost does wind power generation cost? But who cares as long as your friends think of you as superior in your Earth-first rightousness? Does it take more oil to make a solar cell than it returns? Who cares as long as it make you feel better to be known among peers as an Earth-friendly individual. Would be had, in general, some simple understanding of economics, engineering, a little physics, and human nature, the advocates of solar electric energy, wind energy, alt-energy, alt-alt-energy, fusion power and electric cars would find some hostile ground. It is with no little frustration, I find most cannot fathom a little of all four. As an electrical design engineer with reputation, I will be happy to help with projects involving cheap, nonsensical, or free energy devices at reasonable market prices.

Lightmeow, what do you mean by the torque is to high? Is it jumpy; rapid velocity changes? ---------------------------------------------------------------------------------------- I did a bit of research on electric power skate boards ~5 years ago. For best power density at low torque, which is what you need, the Axi Outrunner series motors were nearly the highest at that time. They are used on model airplanes. Anything much better, in electric, is probably fantasy. Highest usable power density batteries available are Lithium polymer, as far as I know. So how do you get the required power density crammed into some footware so you can zoom around? I don't know. But, all and all, electric power has nowhere near as much power density as nitromethane used in a two stroke engine. But the torque range is narrow. The technological challenge would be the transmission.

OK, I give up. What's special about water: Temperature of vaporization, thermal conductivity, heat of vaporization? Ammonia and chlorofluorocarbons are used in refrigeration units. How do these compare to water in physical properties for use as a working fluid for power generation?

Good catch. These things have nearly gone obsolete for a long time now. I should have said, 120 VAC.

Thanks for all that. I especially enjoyed you're multiple comments on 'context'. Perhaps you can help me resolve a contextual issue. Refer to Weinberg, QTF, volume 1, section 5.9. The discussion begins expressing the need for gauge invariance. By eq. 5.9.30 the need seems to have been dropped, where the temporal component of the vector potential must vanish in all inertial frames. However, if we begin with a Maxwell's equations, then reconstruct using a complex (or real) gauge invariant vector potential on a pseudo Riemann manifold, we can eliminate all 8 equations, and replace them with physical correspondences. This reduces to the dynamical constraint dJ/dA=0 upon demanding extremal action. The contrast is large where, 5.9.30 assumes the Lorentz group. Weinburg's context seems to be only flat space time. We seem to have at least two points of difference. I'm sure Weinberg will correct the context of quantum field theory in volume 2 upon a more realistic manifold, though I don't posess volume 2. Do you?

I really have no idea what you are asking for. Could you be more specific?

ha ha for the "wait for it" thing. what's an index and how is it causal?

"Well, Her Einstein, you think you know better than Newton. If all this stuff is relative as you say, then if clock A is faster than B, B should also be faster than A, you pretentious fool."---or something like that. Folks, it occurs to me that there is a way to the bring symmetry back into the mix. md216-- Two clocks, A and B, pass each other in relative motion. Instead of using your "C" clock, I will call it " B' ". Now let us include an A' clock, as well, in a symmetrical way. A' rushes back and meets-up with B. We can do the the comparison of A and B', which is what all the fuss was about, but also compare A' and B. Now everybody is happy. B' is slower than A, and A' is slower than B. We have both the symmetry demanded by the critics, as well as special relativity. phyti-- This discussion of the twins paradox is perpetual. There seem to be two major camps. The critics who are still skeptical and the freshmen who have an epiphany they credit to acceleration while still harboring notions of universal time.

Yes it is. To refract: to deflect.

Nice start. Now do it with mathematics or no one will care. Beware, mathematics can be a harsh mistress, and tell you that what you want, you cannot have.

That which you have written, that I have place in bold text, is exactly correct. And well written. (Better than I could do it.) That which I did not bold I did not understand. In fact, this construction better captures the asymmetry of the twins "paradox" better than most. Recall that the objections to relativity theory were due to an incorrect comparison of symmetry of clocks implied by relativity and symmetry of velocity. You have illucidated that the velocites are not symmetrical in the twins 'paradox' scenario. This is a very long thread, so I haven't read the ensuing attacks, and have no desire to wade through them.

To be precise, r is the perpendicular distance to the ray traced by the velocity vector of the center of mass of the object (within Newtonian physics).

My thoughts as well. No one seems to have seen the elephant; define machine.

You can buy 12 volt neon lamps. The neon is at low pressure. I would expect that it is much harder to ripe an electron out of an orbital, such that it would require a higher voltage, less pressure, or smaller distance between electrodes. You can purchase helium lamps requiring perhaps 15 thousand volts with a tube length maybe 15 inches. 15K/15 gives you 1000 volts per inch of electric field strength. It's not the applied voltage that matters, but the voltage per inch, or voltage per centimeter. That means you need an anode-cathode gap of less than .033 inches. (Hmm. That seems a little large to me.) But it gets a little more complicated than what I've written: There is an ignition voltage to get the arc started, but a significantly lower sustaining voltage. Once you get it kick started it takes less voltage to keep the arc going. By the way, with a missing electron, the helium would acquire a positive charge.

By "photon" do you mean a tiny-little point having electromagnetic characterics? If we try really hard, we can we can compare two frames of reference, each with velocity c---almost. In relativity we can compare more than inertial frames. When you do this, with an "almost c" velocity, a velocity of c+h where abs(h) is the less than any number you can think of, but great than zero, you would obtain some interesting results. In these frames we have a coordinate system collapse. Not surprising, considering we dealing in numbers not finite. Each frame in normal spacetime has 2 finite dimensions, one transfinite, and one that is infinitessimal. Each frame is independent, having no finite-time communication with the other. It is as if these hypothetical photons each had their own universe. What where you saying about photons?

Is special relativity is a good approximation of spacetime? Then so is invariant mass--an approximation, only. My intent: I have learned a great deal from reading the questions of neophites. Certainly more than the accompanying answers of those who might call themselves experts. However, that is not to say, I have not learned a great deal from these as well. How is the house of physics today? Is it well constructed? It's in disarray. But this doesn't stop the carpenters from constructing new additions of the same decayed material. This will not persist. This is offers opportunity, unrequenchable. I make some simple calculations, and viola, light has non-zero mass. Why should this be when another calculation says it is exactly zero? My intent is to provoke, in the hope to learn. Relativity theory is fairly concrete. I can make a statement about relativity and be either right or wrong within the bounds of theory. I can always feel confident in my response by appeal the work of respected men. They can argue with Einstein, etc. if they don't like it. Quantum theory, by contrast, is anarchy. Without an interpretation, even the question of mass is ambiguous, though relativity also has its allotment of peculiar issues. If I were hell bent on expressing superior knowledge, I would be expounding in homework help. I am not so much. Though I am hardly sophomoric, I am a student hoping to learn.

You're reminding me of the good old days. With the advent of the calculus we were getting somewhere, then. Better than today's plodding misconstructions. But there were still disagreements that persist today. http://www.studyphysics.ca/newnotes/20/unit04_light/chp1719_light/lesson57.htm Who was right, Newton or Huygens?