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Is Einstein's theory of relativity able of solving the twin paradox? When the traveling twin turns around to reach Earth, it observes a blueshift of the light emitted by Earth instantaneously, not after some time. This seems to suggest that the blueshift arises from the twin's own acceleration and therefore its own motion through ether, not from the apparent movement of Earth relative to it. The Earth, on the other hand, must wait for the blueshifted light from the traveling twin to reach it at the speed of light. This seems to indicate that the observational symmetry of special relativity is not physical, but that there might be an underlying asymmetry as proposed by Lorentz's ether theory. Here is another line of reasoning that leads to the same conclusion: Consider two bodies, A and B, in relative inertial motion. A accelerates and immediately observes a change in the relativistic Doppler effect of the signal emitted by B. It then stops accelerating. This change in the relativistic Doppler effect is composed of a kinematic and a transverse Doppler effect component. According to Einstein's relativity, from the point of view of A, the change in the Doppler effect arises from the change in B's motion. It includes the transverse kinematic Doppler effect component, therefore B undergoes a change in time dilation. However, this change in the transverse Doppler effect does not originate from a change in B's motion but from A's acceleration. We are certain of this because it appears as soon as A accelerates. If it came from B, A would have to wait for it to propagate from B to A at the speed of light before perceiving it. Since the change in the relativistic Doppler effect does not originate from B, B cannot experience the change in time dilation. On the other hand, since A causes the change in the Doppler effect, he undergoes the change in time dilation but observationally perceives it as happening to B due to the perfect symmetry of the relativistic Doppler effect. Indeed, A can always imagine that the signals it receives are distorted by the change in B's motion since the observed deformation is the same as if B had changed its motion. However, since A knows that the change in the Doppler effect arises from its own acceleration, he knows that he is the one experiencing the change in time dilation. Here a citation by Langevin : https://fr.wikisource.org/wiki/L’Évolution_de_l’espace_et_du_temps

Conflating cultural and biological aspects generally makes poor arguments as it pre-supposes some natural order that folks should adhere to. While I am not (yet) saying that this is the case here, it is often a tactic used to push a narrative under the guise of "just asking questions", as we have seen in the past. So far OP seems to continue to ignore clarifications and counter arguments, though.

Pretty sure there's a x-post here with @exchemist so briefly: If we're starting from your declared position of maximum attraction, we're moving against an attraction force for 900; then with a weakened repulsive force (poles wide apart); then against the same repulsive force; then finally with the mirror image of the attraction of the initial power stroke. In the absence of a proper mathematical analysis, by symmetry we have a nett zero sum. And then there's cam friction and the hysteresis braking mentioned earlier. Granted I've ignored secondary effects of the movement of the magnets themselves but frankly, that's beyond my pay scale. Suffice to say, if there was anything to see here, Faraday would have found it back in the day I think. Looks right enough, so you've got the 1800 phase shift covered. Shall we leave the +/-900 phase shifts to the OP?

But you are not only asking questions. You are making contentious assertions - or at least advancing contentious opinions - too. You say it seems that the male of the human species is becoming less relevant. You cannot expect us all to go along with this without challenging it, because it is patently ridiculous. The human male has dominated human societies for millennia and a quick glance at the sex of those occupying positions of power and influence in modern societies will show you they are still predominantly male. We can't just answer your questions, if your questions start from a false premise. Surely you must understand that?

OK. As I understand it, the idea is inserting the tab, or finger, causes the magnets to be attracted to it, instead of repelled from one another as they are in the previous phase of the motion. If we describe the operation in terms of an engine cycle, there are 4 phases:- 1) magnets close together no tab inserted, high energy of the field 2) magnets have moved apart due to mutual repulsion, reduction in field energy. Work imparted to output shaft 3) tab or finger inserted into the gap, causing magnets to be now attracted towards it, with further lowering of field energy. More work output to the output shaft (and some work output to the input shaft as well, due to the attraction) 4) tab removed from the gap between the magnets, which are now close together. This replaces the force of attraction to the tab or finger by mutual repulsion of the magnets, which are now at close separation, i.e. back to (1). It is this step that requires the substantial work input which returns the stored energy in the field to its stating value. Failure to realise the work need to do this is what can lead the incautious designer to think he has an over-unity machine, as the other steps all involve extracting work from the magnetic field. At least, that is my energy-based analysis of this machine.

Over unity is the same thing as what is traditionally known as a “perpetual motion machine of the first kind”, i.e. one that claims to break the 1st law of thermodynamics. So it’s not a slur. There have also been ideas for perpetual motion machines of the 2nd kind, which claim to break the 2nd law of TD instead. As I have mentioned, it can be good sport to spot the flaw in the logic of the designer. A rule of some patent offices, e.g. the US one, is patent applications for perpetual motion machines will only be accepted if accompanied by a working model. Which they never are, of course. So recognising perpetual motion machines is something patent office examiners (as Einstein once was,incidentally) and patent agents have to be able to do.

Monopoles is an interesting study for example it's potential would fall off at 1/r as opposed to 1/r^2 for dipolar, 1/r^3 for quadrupolar ie the combination of two dipolar fields. As opposed to quadrupolar in gravity waves. Boit-Savant law can be uses to solve for the above if I recall.

Both: we’ve solved the conundrum presented by your machine, I’ve revised some magnetism I haven’t looked at since school, and you’ve become motivated to learn more about it. And for me, another perpetual motion machine bites the dust, which I can add to my tally.

In return, perhaps you could clarify something for me. What is the phase relationship between magnet pole separation and finger position? If we define zero degrees for the disk when a finger is directly between the poles, and zero degrees for the poles as minimum pole separation, then what phase difference between the two should we consider for optimum performance? And how is that optimal phase difference maintained?

One important difference, though, is that in the OP's machine the poles of the two magnets are opposed so that they repel. The region in which the fingers on the input disc move is in principle an area in which the field lines will be squashed outwards in the plane of the fingers of the disc.

Perhaps one way of looking at this contraption is to compare it with a Faraday disk (aka homopolar generator). In the latter, both motion and induced current are in the plane of the disk with the magnetic field perpendicular. The OP is rotating this so that motion and magnetic field lines are in the disk plane therefore forcing induced current into the perpendicular. However, different portions of the disk will see different current polarities depending on whether they are moving towards or away from the magnetic poles. In particular, the portion of the disk passing directly between the poles will see a sharp switch in polarity and consequent current flow component appearing in the disk plane. This will in turn deflect the magnetic field lines somewhat out of the disk plane as if attracted by a temporary opposite pole. I don't know whether it's a good picture, but in my mind's eye, I'm seeing this induced temporary pole falling into a potential well only to climb back out as it departs with no nett overall energy change in and of itself. However these circulating currents are a different matter as they will add a time lag to the ideal case making ascent harder than descent, acting as a brake in exchange for simply heating up the disk.

OK, in that case, what I think you will find is it takes significant effort to pull the finger out of the gap, as the force of attraction is stronger once the magnets have moved inward, than the force that pulls it into the gap when you insert it. So you do net work on the system that way and this provides the energy that restores the stored energy in the fields to the status quo ante.

OK, now we get to it. In your proposed machine, the magnets first repel one another, doing work and lowering the stored energy in their respective magnetic fields. You believe that when you insert the steel finger between them, they will then be attracted towards it, doing more work and further lowering the stored energy in their fields. And then, when you move the finger out of the way, they move apart again due to repulsion, extracting yet more energy from their magnetic fields. This obviously cannot be the case. So there is something wrong with your assumption. Either you will find the magnets are not attracted together when the steel finger is interposed, or you will find the finger resists being inserted or removed, such that the operator has to do work against the field, thus supplying the required energy. At the moment (being a chemist rather than a physicist) I am not sure which of the two it is, but logically it must be one or the other, it seems to me. My suspicion is that the magnets will not be attracted to the finger. If you consider the path of the flux lines when the finger is in between, they have to turn sharply horizontal within the finger and pass outward to each side. This I think means the dipoles within the finger will not be able to align themselves with either field in the way that you (implicitly) suppose, as they will be perpendicular to the fields, and so no attractive force will result. If that's right, you would be able to twiddle the finger wheel as fast you like and bugger-all will happen! But perhaps you should build it to confirm exactly how it fails to work.

Ahem....

The most basic electrical devices consist of the following elements: a resistor, a capacitor and an coil. https://en.wikipedia.org/wiki/Resistor https://en.wikipedia.org/wiki/Capacitor https://en.wikipedia.org/wiki/Inductor The most basic electronic devices have the above elements plus a diode (or equivalent vacuum tube), a transistor (or equivalent vacuum tube), integrated circuits, microcontrollers, and processors. https://en.wikipedia.org/wiki/Diode https://en.wikipedia.org/wiki/Transistor https://en.wikipedia.org/wiki/Vacuum_tube https://en.wikipedia.org/wiki/Integrated_circuit Integrated circuits, microcontrollers and processors are programmable, that is, they execute a program that someone wrote and upload to them or to RAM and/or ROM. Where stands your "steel wool" with the above?

Logically incorrect, even if the premise is true. Equivalent to “All dogs are mammals. I am a mammal, therefore I am a dog.”

For once, we all agree!

The idea of fast food parodying healthy food can be the same for many drugs being a victim of their own karma. For example alcoholics might dislike being highly extraverted by overdrinking with others to try and disprove how ethical they were to talk to one another. Humility is very ethical but is easily hijacked by perversion. For example marijuana might make those already prone to spirituality to downplay their spirituality by attributing too much of their insights to drugs when a lot of their thinking might still have been internal. Wiz Khalifa - No Sleep Yet another factor in obesity is that a lot of athletes can be too emphatic without being sexy enough. The dilemma is that many top athletes are able to be sexy if they tried to be but are often unwilling to let slightly less hardworking athletes be viewed as sexy. For example as a teenager I always counterbalanced cardiovascular exercise with weightlifting because no matter how strong and handsome bodybuilders and marathon runners can be they often downplay how nice they are by not being slightly androgynous. As such no matter how superior I try to be at walking I can always mislead others into how egalitarian I can be just to pride myself on walking stamina!

Offering light criticism can often be a backhanded way to downplay just how threatening other people could have been! I feel the entirety of China could be sacrificed in any nuclear exchange just to achieve destruction of critical targets in the west!

Think about it: the brain is nothing different than electricity flowing through wires. The brain is an electricity-producing machine. That's what we are. And electricity flowing through wires produces magnetism. And maybe, magnetism = consciousness.

One reason sweets can be addictive is that healthy food is almost unlimited such that healthier people would still be outcompeted by even healthier people. I’ve never ate a whole raw lemon and lime until now where I had plenty of lemon and lime juices in the past. So many sugary sweets during childhood are almost mere preparation for how extreme it could be to eat lemon and lime slices. I ate the lemon yoghurt afterwards as a recovery warm-down! I put a handful of raw popcorn in my mouth on a drive to the beach and it took the full 30-minute length of the journey for the popcorn to melt in my mouth before it became chewable and ingested. Yet in spite of the blandness the raw popcorn was as great as chewing gum in distracting you from overeating other foods.

The cmb is sending light through a cone but the galaxy's actual position is about a half sphere When I'm in the mood