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Everything posted by MigL
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I think you hould quote all of Joigus' post But even if he could What information, other than the collapse of a mathematical construct ( wave function ) of a model, would you be able to send ?
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Some questions on Blackholes
MigL replied to AbstractDreamer's topic in Modern and Theoretical Physics
The Event Horizon is essentially a mathematical construct, however, it is also the manifestation of the space-time geometry. As such, it is modified by properties like mass, charge and ang momentum ( in size shape and complexity for lack of better descriptors ). I don't quite understand the Beckenstein-Hawking mathematics, but it is a statistical mechanical interpretation of 'micro-states' of an EH ( as opposed to the previously believed single state of the 'no hair' theorem ) which leads to BH entropy. ( these micro states also arise in LQG, where they have a geometric interpretation ) As the EH is not an 'edge' to space-time, but rather a 'threshold', any curvature continues along with the global geometry through the threshold; BHs do experience gravity from external objects. What is a 'graviton' wave ? Gravitons are the supposed result of a quantum field theory of gravity. Our current theory, GR, is classical; unless you are S Hawking, it is best not to mix the two. -
Most people ( myself included ) have no formal training in the application of ( mathematical ) logic. But they watched Mr Spock on Star Trek, and think that using the word makes them sound authorative. Rational, reasonable and sensible imply that a decreasing amount of thinking has gone into forming that thought or opinion, but there may be no formal logic involved at all. Then again, I'm sure some amount of thinking goes into irrational, unreasonable and insensible thoughts and ideas also, in which case none of them mean what we intend them to mean.
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Absent other variables which influence it, how would you be able to tell if time is constant over time ? GR, a geometric theory of gravity, tells us that gravity is mostly due to time axis curvature. IOW, time progresses differently in flat space-time, as opposed to curved space-time, and is definitely not constant.
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Some questions on Blackholes
MigL replied to AbstractDreamer's topic in Modern and Theoretical Physics
I would add a more simplistic elaboration to Joigus' Feynman diagram/virtual particle explanation. The conserved quantities, mass, charge and ang momentum of a Black Hole ( classically ), as well as entropy ( classical/quantum hybrid ), which leads to temperature, and Hawking radiation, are all encoded in the Event Horizon. No other feature of a Black Hole, other than the EH, are evidenced to the outside universe. -
Agred. And that's what makes the central singularity unphysical. We obviously need something better suited to describing hi-energy/lo-separation behaviour of collapsed matter than GR is capable of.
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Space and time d not trade places. This is a misconception due to the re-orientation of light cones in strongly curved space-time. Rather, all geodesics, paths through space-time, within the event horizon, lead to the central singularity; and none extend past that point.
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A very interesting question, but I do think you need to provide some 'direction' as to what you are really asking us to answer. I prefer any system that gives me, and any others who may wish it, a considered voice and a choice. If you want to call that democracy, then I'm all for it. But, like all other systems of governance, it does have drawbacks that we have to put up with.
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No it isn't correct because the gloves would need to be in an undefined state while in the boxes. But correct enough to illustrate that there is no information transfer, superluminal or otherwise.
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What 'black box' are you referring to ? Say I take a pair of gloves, and put one in one sealed box, and the other in another sealed box. I give you one box and a plane ticket to Australia, and the other box to Joigus. Neither of you knows which glove is in your box. When you get to Australia, you open the box, and find a right-handed, or left-handed glove. As soon as you've done that, you immediately know the handedness of the glove in Joigus' box, as they are correlated by pairing. No information transferred, and the only 'black boxes' are the ones that held the gloves. ( this is a thought experiment; buy your own ticket to Australia )
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The American system has its own set of specific problems. You did it now, Joigus. You've dipped your feet in the political waters. Soon the undertow will drag you right into the sea of mostly opinions, and few facts.
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From John's link "A symmetrical airfoil like the Avistar’s develops lift using only Newton’s Third Law. But a flat-bottom wing like the NexSTAR’s obtains lift using both Newton’s Third Law and Bernoulli’s Theorem. Therefore, for a given wing area, a flat-bottom wing produces more lift at a given airspeed and angle of attack than would a symmetrical wing with the same conditions. This is why all basic trainers utilize a flat-bottom wing. Aerobatic trainers use more symmetrical wings because these airfoils develop the same amount of lift whether inverted or upright. This is good for aerobatic flight, but not usually required in a basic trainer. Semi-symmetrical airfoils have some airfoil shape on the bottom but a lot less than on the top. They use a little Bernoulli and a lot of Newton to develop lift. These airfoils develop more lift than symmetrical ones but a lot less than flat-bottomed airfoils. They also sacrifice some aerobatic performance." It seems to indicate a component produced by Bernoulli, which might be lacking in aerobatic aircraft because of the need to fly upside down. Wings are very complicated, and trade-offs are made to tailor the plane for a specific flight envelope. We won't even consider effects like recirculation, vortex flows, and methods, like camber, of keeping flow as laminar as possible over the wing surface before going to turbulent at high alpha.
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There is no information transfer faster than the speed of light. Of any kind. Period.
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Sure John, a flat fin at an angle of incidence would work, and probably produce more lift than a classic streamlined 'D' shape ( like a Clark Y ), but I can't imagine it would do any good for your lift/drag ratio, and you would have trouble keeping it in the air as a result. I realize there are many factors which contribute to lift, but I thought we were explaining specifically how Bernoulli makes its contribution. According to Bernoulli, the fluid needs to move faster, creating a localized area of relatively lower pressure, resulting in 'lift'.
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Let me give it a try ... Take a square sross-section pipe of a given length. Introduce a fluid ( air ) at one end. In the absence of 'sinks' or 'sources'. we expect the same amount of fluid to come out the other end. If we now constrict the pipe by attaching two 'D' shaped plates to the top and bottom, we still expect the same amount of fluid out the other end. But to pass the same amount of fluid through the constriction, the fluid must move faster ( reduced cross-section ). What can cause the fluid to move faster ? Pressure, of course. It must be higher before the constriction , to cause the fluid to speed up through the constriction where it is lessened, and higher again after the constriction to cause the fluid to slow down. That is Bernoulli in a nutshell. We now employ a trick familiar to aerodynamicists. We move the upper part of the pipe, with the 'D' shaped obstructions, out to infinity, and consider only the lower 'D' shaped obstruction and the streamline above it. The fluid still speeds up going over the obstruction, and as a result, pressure is lessened ( compared to undisturbed fluid far away ). That is how a 'D' shaped surface, such as a wing, sees decreased pressure above, compared to below, and generates lift.
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We also have a first-past-the-post Parliamentary system, here in Canada, where about 35 % of the votes will give you a majority government. However, when a government falls in most other such places, an election is called. I don't see why a person, elected only by her party members, gets to govern over a country for 3 years; doesn't seem like democracy, does it ?
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She had little to do with governance, Zap. Mostly she was a figurehead; a reminder to the British people of days gone by. It may be hard to believe, but her 'job' was very demanding, as she had to keep up 'appearances' and could not enjoy the simple pleasures of family and friends that most of us take for granted. The rest of her family, including the new king in waiting, seem to be failing miserably at that job. She kept the monarchy going, and, for better or worse, I don't believe it will last with her gone. May she rest in peace.
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Your entire premise is wrong. You cannot measure anything in your frame of reference/gravitational potential level that indicates gravitational time dilation. It is only comparison to higher or lower potential that evidences GTD.
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So this 'problem' is based on A Einstein's quote, and his quest for a Unified Field Theory ? That, because geometry is used in building one model, GR, it should be used for all physical models ? And the fact that geometry lacks a basic 'consistency' ( for lack of a better word ) means that it cannot be used to build all other models ? Have I got it straight ? Geometry, and all of mathematics, are tools, used for physical model building. There is a vast difference between the physical 'reality' ( whatever that is ) and the model we use to describe it and make predictions. And 'tools' don't require 'consistency/coherence'; I certainly don't expect that from my hammer and saw. Incidentally, A Einstein's search for a Unified Field Theory, was, at best, misguided. Kaluza-Klein had some promise, but that was before anyone had any consideration for the 'strong ( color ) interaction, and the weak interaction.
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A rant, with few solutions offered, but kind of funny ( if you don't live there ), and probably spot on. So why are these people not getting voted out of office ? edit : This Jonathan Pie guy is hilarious. Just watched his 'tribute' to Boris Johnson Again, why are thesepeople getting elected ? ( at least the Americans had the common sense to get rid of D Trump, although he doesn't seem to get the hint )
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I suspect most of us will stay out, and it has nothing to do with being rude. We come here to discuss, not to be preached to. This is your second go at it, and we still don't have anything worth discussing. Sh*t , or get off the pot ! ( i guess you bring out the 'rude' in us )
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Mistermack should realize that, in the West, he is free to spout his dissenting nonsense on any website, newspaper or assembly area he chooses. Meanwhile TheVat would be in serious trouble if he chose to post his 'dissenting' views in Russia. Makes choosing the more credible information, or referendum polling, much easier to anyone who isn't a 'useful idiot'. No sense setting the bar too high ...
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JC ( MacSwell, not John Cuthber ) seems to have the Canadian perspective on this. In Canada, government workers have great job security; they simply cannot be fired, no matter their competence, or performance. The employer/employee power dynamic is different at differing times and for different jobs; sometimes it favors one, sometimes the other. Recall that one of the major reasons for the begnning of the end of serfdom in Europe was the death, by the Black Plague, of 1/3 to 1/2 of the workforce, putting the remaining in a more favorable position to demand more for their work.
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Sometimes I need a drink when wondering why you make it a point to seriously reply to obvious humor ...
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Were you having a few drinks on that balcony, Seth ?