tar Posted August 18, 2015 Author Share Posted August 18, 2015 she would absolutely be able to tell which direction she was going and how fast, even though the light from ahead and from behind was coming in at c it would be coming in at highly diverse wavelengths and energies Link to comment Share on other sites More sharing options...
Strange Posted August 18, 2015 Share Posted August 18, 2015 she would absolutely be able to tell which direction she was going and how fast, even though the light from ahead and from behind was coming in at c it would be coming in at highly diverse wavelengths and energies What? Who is "she"? Link to comment Share on other sites More sharing options...
tar Posted August 18, 2015 Author Share Posted August 18, 2015 Strange, The correct way, a correct way, same difference. We don't know the correct answer for how the twin will come back. It's speculative. If I think she will come back aged approriately along with everywhere she has been, and she comes back exactly as old as her twin, then the prediction would be wrong. Every prediction of relativity has been found to be consistent with every prediction of relativity. You say: "But there is no correlation between relativistic effects and the presence of electromagnetic radiation." I say that if gravity effects time and distance and motion effect time and distance, that light should also be in the mix, when considering time and distance, since distance is defined in terms of the time it take light to make the trip. You would not observe a relativistic effect, unless electromagnetic radiation was part of the experience. How you define here and now, at each part of the experinment? You need the tick of a clock to either be happening some place within the experimental space, or everywhere within the experimental space, at the same time. How can you say a photon is over there, because you see it over there, when it just hit your eye a few milliseconds ago? There is enough "slop" in an experiment to cause timing differences, just due to definitions as to what is currently happening, and what that means. That is the point of this thread. That there are "problems" with the block universe idea, and there are "problems" with the two senses of now being incorrectly switched between. Regards, TAR I was going back to having the traveling twin female and the stay at home male, so one could just use she and he, rather than Earthman and Spaceman or stay-at-home and traveler. If relativistic effects are considered "without" regard to the blue shift in the direction of travel, and the redshift in the direction of where you have been, then the experiment is not taking everything into account. If for instance the inclusion of the high energy, high frequency "short" wavelengths from the front, would be mathematically equivalent to "length contraction", then let's just go with the shorter wavelengths, which are real, and dispense with the length contraction, which is goofy. -1 Link to comment Share on other sites More sharing options...
Strange Posted August 18, 2015 Share Posted August 18, 2015 We don't know the correct answer for how the twin will come back. It's speculative. Of course it isn't. The experiment has been performed and, like every other test of relativity, reality confirms the theory. Every prediction of relativity has been found to be consistent with every prediction of relativity. That is an idiotic statement. However, every prediction of relativity has been found to match reality. The only other people who deny reality to the same extent that you do are those young-Earth creationists who say, "if reality and the book disagree, then it is reality that is wrong." I say that if gravity effects time and distance and motion effect time and distance, that light should also be in the mix, when considering time and distance, since distance is defined in terms of the time it take light to make the trip. Then present the evidence to support your "hypothesis" (in the Speculations forum). There is enough "slop" in an experiment to cause timing differences, Please provide the experimental data and calculations to support this claim. (I assume that will be pretty easy for you.) (The remaining incoherent rambling skipped.) 1 Link to comment Share on other sites More sharing options...
tar Posted August 19, 2015 Author Share Posted August 19, 2015 Strange, I apologize for calling length contraction goofy. I mean to say that it doesn't make any sense, as to what it "means". Would you say that something undergoing length contraction "actually" gets shorter? Perhaps I have a different way of looking at reality, but I don't think that automatically means that I am ignoring it. I could reverse your charges and claim that you are ignoring reality when you say there is no universal now, when there absolutely has to be something going on now, at a distance, for us to see it later. Block universe is one way to parse it. You have the 45 degree angles and length contraction and time dilation, but you have nowhere to start, and nowhere to hang your hat. Two senses of now is based on the findings of relativity, but does not draw the same conclusions. I am considering what must be the case for what we sense to be what we sense. It is difficult to claim a thing that we cannot witness as real, but we, and I mean everybody, do it all the time. I started with reminding everybody that everybody KNOWS a star is shining in two senses. One in that we see the thing, and one in that we know it is sending out photons now, that we will see later. This is real. Nobody denies it. What I am suggesting is that our ability to put ourself in somebody elses shoes, is powerful, but is not flawless. The universe is very big and light takes minutes, hours, days, years, millenia, epochs, to get from certian parts of it, to other parts of it. Each set of timings, creates a different type of model, in terms of what parts of it are verifiable and viewable, on what time scales, and by what observers. In the twin paradox, I have read many a take, and seen many a breakdown of what is happening, and in most, I do not agree with how certain things are defined, and whether the thing that is being said is "true" from every perspective. Since the universe is connected, there are no two parts of it, that are not connected to each other. No item can escape reality. No item can be somewhere else. It has to be here. But what is here? Here is half a million miles, give or take, if you go by local, here and now. Here is the entire universe, if you go by the universal now. The problem is, and the basis of the insight that I am trying to share, is that it must be true that another person is real, and existent even though he is over there. Separated from you by a pico second or a nano second or a millisecond, or a second, or 14 minutes if he is on Mars when Mars is on the other side of the Sun from "here". This is a problem, because in order to see reality as it is, one has to look at it twice. Once from what we sense, and once from what we know that means. It is easy to accept the reality of distances within a half million miles, because you can interact with something at that distance, within a moment. The concept of what is real and existant though, has to change character, as you increase the distance beyond the moment, because the thing only exists once, yet you can't see it as one thing, because you are not close enough to interact with it, in a moment. It has to be "You know that star put out the light we are seeing years ago, right? And that star is doing something right now, that we won't witness for years." Real small and quick and close stuff, stuff that happens well within a moment can be more readily understood, because even though we can't see it happening, we know the start and finish of each cycle is complete and past and done, by the time we see it. Not so with the shining of a star. What we see is already done, but the star is still shining now, and we have no way to see it, other than the way we do. We have to imagine, what has to be real. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 19, 2015 Share Posted August 19, 2015 (edited) Would you say that something undergoing length contraction "actually" gets shorter? What does "actually" get shorter mean? It is an actual, measurable effect. Is that what you mean? I could reverse your charges and claim that you are ignoring reality when you say there is no universal now No, because when we ask reality it confirms our theories and tells us that there is no universal now. Just looking at the title of this thread again, I don't see any contradiction between the "block universe" view (not a term I like very much, BTW) and your "two nows" concept. Your two "nows" are just two points on a worldline (a null geodesic, in the case of photons) - one is the event where something happens and the other is the event where you see it. The only difference seems to be that you claim that everyone will agree on "when" each of these events occur (both in absolute terms and relative to one another); while relativity theory (and therefore reality) says that the "when" of each event is determined by the choice of coordinates, and that is dependent on things like the relative state of motion of the observers. [edited for clarity ... I hope] Just to add a bit more... What everyone will agree on is the "interval" between the two events (roughly, the 4D distance between the events in space-time). For something that involves light being emitted from a source and seen by you later, this interval is zero. Edited August 19, 2015 by Strange Link to comment Share on other sites More sharing options...
tar Posted August 19, 2015 Author Share Posted August 19, 2015 Strange, OK, perhaps we are getting somewhere. The difference between what I am imagining and what relativity says is that null geodesic thing. That there is no difference, in terms of being a coordinate (4D) between the release of the photon and the reception of the photon, regardless of the distance between. This appears to be my problem in understanding a number of issues, or to put it another way, my problem WITH the theory. Perhaps strick adherence to this null geodesic thing, at the inappropriate time and place, is the problem with the theory...in my estimation. This issue is probably why things you are saying seem like nonsense to me, and things I am saying seem like nonsense to you. The problem may be forced by the math, as it allows the speed of light to be considered as unity, and therefore not accounted for in the transition of a particle, or a thought from one place to another. It forces the "reality" that to a photon, there is NO distance between two x,y,z coordinates, and it strikes another electron, on the other side of the galaxy, as soon as it is released from its mother atom. This is actually contrary to experience, and light has a speed of 186,000 miles per second. Or contrary to convention where we have set a meter to be the distance traveled by a photon in 1/299,???th of a second. There appears to be a difference between the photon experiencing time, and a person experiencing time. We go by what lots of photons are doing, in succession, and that is what reality is made of. The sum total of all the photon trips. And to us, being at the receiving end of a photon's trip, we can order its arrival in terms of the arrival of other photons, released from other x,y,z coordinates, and we can order it, in terms of other photons released from the same x,y,z coordinates, and we can put ourselves in the shoes of observers, between the release and reception of a photon and see that they can eat a sandwich, "while" the photon is in flight. So to the photon, there is no distance between, according to relativity. According to the two senses of now, there absolutely IS a distance between and a fixed time it would take a photon to travel it. And a fixed time it would take a twin to travel the distance. I can understand the argument that if the photon makes the trip in 0 seconds, then something moving at the speed of light should also make the trip in 0 seconds, and that it is impossible to actually have a mass go at the speed of light, so we can imagine something going near the speed, call it relativistic, and say that anything going near the speed of light will experience time and distance close to null, by a factor dictated by the pythogorean theorum. This is fine, if that is all the theory is saying. Except saying that "this is reality" is somewhat short of the mark. Reality for me, and for you, and for any other human is formed by the arrival of photons, and electromechanical fields, and temporal disturbances, and chemical combinations, and heat and energy to our sense organs. Our brains put it all together and build a model of the world, consistent with the information gathered. This process relies heavily on the speed of light, as distant items do not inform us of what they are doing currently, they inform us of what they did a while back, at a distance exactly coincident with the not 0 speed of light. Regards, TAR so when we say the twin is traveling at 98 percent the speed of a photon, and the speed of a photon is infinite, as in being able to transverse infinite distance in 0 time, what do we mean? Link to comment Share on other sites More sharing options...
Strange Posted August 19, 2015 Share Posted August 19, 2015 That there is no difference, in terms of being a coordinate (4D) between the release of the photon and the reception of the photon, regardless of the distance between. I'm not sure what you mean. The two events take place at different (4D) coordinates. What do you mean by "no difference"? The problem may be forced by the math, as it allows the speed of light to be considered as unity, and therefore not accounted for in the transition of a particle, or a thought from one place to another. It doesn't matter if you set the speed of light to 1 (in Plank units) or 3x108 m/s or 2x1012 furlongs/fortnight it is always accounted for in the time it takes for a particle to get from one place to another: it can never do it faster than light, and if it has mass it can never do it at the speed of light. Where do you get the idea that the speed of light is not accounted for? It is fundamental. It forces the "reality" that to a photon, there is NO distance between two x,y,z coordinates This is just nonsense. Perhaps if you could get rid of all these weird misconceptions that you keep inventing, you would be able to appreciate the theory and its rather nice description of reality. To put it another way, every one of your objections seems to be: "the theory must be wrong because it says <insert invented nonsense here>." 1 Link to comment Share on other sites More sharing options...
tar Posted August 19, 2015 Author Share Posted August 19, 2015 Strange, Well does or does not the theory say that the traveling twin will experience traveling a shorter distance than the actual distance, in a shorter period of time than the actual period of time? Regards, TAR Strange, And "a rather nice" description of reality may be a stretch, as it requires one to drop dimensions, contort space and time, and keep track of an amazing number of definitions and contraints and transforms, some of which I personally cannot manage to relate to reality. I quickly lose track of whether I am here or there, twin or me, objective viewer or subjective viewer, in the shoes of the muon, or an ant traversing the inside of the surface of an expanding baloon. I still for instance do not know what it means...what you "get" when you square the speed of light. And it remains a question as to what one is suppose to do with a star that is 4.8 lyrs from here. Are we currently seeing it or not, or both? Regards, TAR does it really exist only once, or does it really exist in two senses, one that we sense, and one that we know must be the case Strange, For instance, let me ask this question about reality. Does a quasar, that we are currently studying exist? Does the area of space where the quasar is also have an existant reality at the present moment, where the masses and gases have undergone several generations of star formation and element building, are currently 13.8 billion years old, same as the Milky Way, and where there may be carbon based life on some planet? Since you may imagine that that area of space is currently doing something that is "different" than a quasar, it is just a matter of convention and agreement as to what we are calling currently existing, and in what sense we are calling it. In the one sense we have to call an old image of the thing reality, and in the other sense we have to call our imaginary concept of what must be, or could be the case, actual reality. It is not ignoring reality, to talk about both the image and the imagination as being real...in the exact way that they are real. Regards, TAR if we see the Mars rover fall into a hole, did it "just" fall into the hole, or did it fall into the hole 14 minutes ago? how many instances of the Mars rover, exist in the universe? I mean actual Mars rovers, not images of what the rover did before, but the actual Mars rover, that is doing something now, for the first and only time it will ever be done? Link to comment Share on other sites More sharing options...
Strange Posted August 19, 2015 Share Posted August 19, 2015 Well does or does not the theory say that the traveling twin will experience traveling a shorter distance than the actual distance, in a shorter period of time than the actual period of time? No. (Not worded like that, anyway.) It simply says that one twin will experience less elapsed time than the other. as it requires one to drop dimensions No it doesn't. If anything, some people are unhappy with the fact it adds one dimension (time) to the three they are aware of. I still for instance do not know what it means...what you "get" when you square the speed of light. What do mean? You "get" a value of 9x1016 m2/s2. And it remains a question as to what one is suppose to do with a star that is 4.8 lyrs from here. Are we currently seeing it or not, or both? If you can see it currently, then you are currently seeing it. (That is an nonsensical answer to a nonsensical question.) if we see the Mars rover fall into a hole, did it "just" fall into the hole, or did it fall into the hole 14 minutes ago? 14 minutes ago, of course. how many instances of the Mars rover, exist in the universe? One, of course. How many do you think exist? Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 No. (Not worded like that, anyway.) It simply says that one twin will experience less elapsed time than the other. No it doesn't. If anything, some people are unhappy with the fact it adds one dimension (time) to the three they are aware of. What do mean? You "get" a value of 9x1016 m2/s2. If you can see it currently, then you are currently seeing it. (That is an nonsensical answer to a nonsensical question.) 14 minutes ago, of course. One, of course. How many do you think exist? Strange, Well, I know what a square meter is, but I do not know what it would mean, to travel a square meter. Would that be analogous to "covering" a square meter, as in pouring fluid on a flat surface, and having it create a larger and larger puddle as you pour? And once I figure out what that means in terms of a photon, what then is a square second? If you are currently seeing something then you are currently seeing it, but that thing you are seeing has already happened, so you are not currently seeing what is currently happening. You admit yourself, that when we see the Rover fall into the hole, it currently has been lying at the bottom of the hole for 14 minutes. Why do you accept the statements of fact and ignore the implications? ... Was thinking this morning about a way to test the "passage of time", as per what I would predict and envision that would perhaps explain better, what I am suggesting is true, about the way the universe is connected to itself. Any observer that is not in the same x,y,z coordinate as another observer will be a different distance from every other x,y,z coordinate than another uniquely positioned observer, at least along at least 1 axis. For simpliticy of concept, we will put the origin of the x,y,z coordinate system, in the real world, not on a peice of paper, or in an analogous fashion in a 2d representation of some sort. For the purposes of the 2 nows point of view, we will have t be zero at every coordinate, now. Already, when you consider Proxima Centauri in respect to Earth it is at t-4.8years and we, here on Earth will see it get its clock set to zero, in 4.8 years. From the universal now type of exercise we envisioned, all points in the Milky Way are set to 0, while all the distances between all points are at an exact relationship. Of course the place immediately continues to rotate around the center, with all items changing their x,y,z coordinates, and ticking seconds off, in respect to the rest of the clocks in the galaxy at a rate such that if you would go to another x,y,z coordinate, when you got there, at whatever speed, it would read the same t as your clock, having been set at zero at the same universally considered moment as your clock, and having ticked off seconds, at 1 sec per second, since, same as your clock. The implications of this view, are that as you approach a different x,y,z coordinate, your times get closer, until you are there, and they match. This time is exactly accounted for by the blue shift of the frequencies of light you see, as you appoach Proxima Centauri. At a certain point on your trip you will see Proxima's clock set to zero, and tick off seconds at a rate faster than your clock, but at such a rate, that when you arrive the clocks are ticking the same second. Having watched the redshifted clock you left on Earth, move in slow motion, you will find, I predict, that when you reach Proxima Centauri, and see Proxima Centauri's clock tick the same second as your clock, you will see the clock on Earth tick the same tick as your clock, minus 4.8 years, which is exactly the time offset between the here and now of Earth and the here and now of Proxima Centauri. To test this idea, I was speculating that you could pick 12 directions in space (similar to the center of the 12 diamond shapes of a spherical rhombic dodecahedron) and in each direction pick a close star, a distant "fixed" star and an item outside our galaxy in that direction and carefully track the redshift or blueshift of each of the 36 items during all 24 hours of the day, for a year, from an equatorial observation point, one at 45 degrees north latitude, and one at the North pole and one at 45 degrees South and one at the South pole. Of course there would be stars you could never see from the North, and items you could never see from the South, but if you put all the info together, you could get a decent "grid" and together with distance calculations, assign an x,y,z coordinate to each, according to the center of the galaxy at t=0, with the positive Z axis pointing to the great attractor, at t=0. Of course there would be some difficulty in building this grid, because the t=0 universal set, will not happen (as we watch) at the center of the galaxy for scores of thousands of years, and the "set" will not "happen" as far as we witness it, for whatever time it takes light to get here from each x,y,z coordinate...but it is the idea I am after, and each distance and time descrepency can be figured and everything, in a geometrical way, will add back, to where there was an actual moment in time, when every item had a unique position in the grid, at t=0. So, if we have the clock ticks (frequencies) of all 36 reference points, and their relative distances to each other we can figure what clock tick, relative to the t=0 set, each item is currently on. Of course most items will be on a negative tick, as we won't see any of the clocks tick to zero in our lifetimes, except for the few stars we have picked within 100 lys. But ALL the clocks were "actually" set to zero at 8:30 AM on the 20th of August, 2015, in West Milford NJ. Giving this setup, we can now run an experiment. Have a "stationary" lab watch the visible of the 36 and see what time it is. Have a moving lab watch the visible of the 36 and see what time it is. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 Well, I know what a square meter is, but I do not know what it would mean, to travel a square meter. Would that be analogous to "covering" a square meter, as in pouring fluid on a flat surface, and having it create a larger and larger puddle as you pour? And once I figure out what that means in terms of a photon, what then is a square second? Why would you want to "travel a square metre"? You seem to be trying to invest a conversion factor with some physical meaning. That way lies madness. 1 Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 You could pick the 12 directions, based on the way the Earth was oriented to the universe, at 8:30 AM on August 20th, 2015. Strange, Well wait a minute. Is that why I have such problems with assigning meaning to equations? There is no physical meaning to equations that are representing the way physical reality works?!? I am glad this discussion is in the philosophy section, because we really do need to carefully parse when we are talking about "what we can say about a thing" and when we are talking about the "thing as it is". david345 suggested that relativity was the block universe The statement made no sense to me. Are you telling me that it not suppose to make any sense. It's just supposed to work on a piece of paper...and that's the way it is? I am thinking that something working or not working in one's head, having the model fit reality and reality fit the model, is a process that is pretty much contained locally, within a few thousand lyrs at a maximum, and more likely something that is occuring or has occured on the Earth, in the last 4 or 5 thousand years. The conventions and language that we have come up with, refer to something, all the time. They are symbols and collections of symbols, that stand for something else, other than just the shape of the character, or the slope of a curve. Even without knowing how to take an integral or find a derivative drivers can judge how to control the speed and direction of their vehical to pass a truck, on a turn on a busy highway, at 70 miles per hour. We can solve the equations, without ever setting them up on paper. If we were to set them up on paper, the numbers would have to mean something, stand for something, we would have to have the road, and the lanes, and the speed and position of each vehical represented at each moment in such a way as a collision on paper would be a collision in reality, and a safe pass on paper would be a safe pass in reality. If you set it up wrong on paper, and make the truck 12.73 meters long because its moving and has contracted in length from its actual 12.74 length, and therefore should fit in the 12.74 meter space between the front bumper of the car behind and the back bumper of the car infront, you better know what is related to what, when lengths are contracted and when they are not, whether the contraction is taking place from front to back or back to front, or all at the same time, or what, or you are liable to calculate a miss when there will actually be a hit, or a hit when there will actually be a miss. The numbers and the symbols have to stand for something OR you have a road to madness. Looking for meaning in the symbols is not, or should not put one on the road to madness. It should put one on the road to making sense of the world, and of making sense of the equations, that attempt to model the world. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 Well wait a minute. Is that why I have such problems with assigning meaning to equations? There is no physical meaning to equations that are representing the way physical reality works?!? There is physical meaning to the equations. For example, you seem to be thinking of e = mc2 (or something). In this case, m has a physical meaning (rest mass) and e has a physical meaning (energy) by c2 is just a number (with the appropriate dimensions). It has no other significance. The statement made no sense to me. Are you telling me that it not suppose to make any sense. It's just supposed to work on a piece of paper...and that's the way it is? Of course relativity makes sense. It is also practically useful for developing technology. Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 I am 61. Within 20 or 30 years, barring some longevity advances in medicine I will most likely die. It will not matter to me, at that point, whether relativity is the block universe, or whether it is more like the two senses of now. There will be people alive after I die, some that can calculate the distance between two events in 4D space time and can visulize a null geodesic, and some that think the Earth must be flat, and some like me, who try and build a model of the universe, around me, consistent with what I sense, what I have been told, and what makes logical sense. If two atomic clocks come back from a flight, one in one direction around the Earth and one in the other, and they do not match, and do not match a clock that never left the ground, then there must be a reason. I am still looking for the reason, because time dilation and length contraction do not add up and add back in all the ways I need them to. There might be another way to look at the numbers and see what is "actually" happening, in terms of the wavelengths of energy that are being counted. It might for instance matter whether the clocks were facing forward or back, or whether some wire in one clock was looped in a different manner than in the other, that only mattered while moving through the electric field of the Earth. But in any case the universe will be exactly the same, outside the local 5000 lyr radius, no mater what I think or you think, or the flat Earther thinks. Relativity cannot be the block universe because the universe existed before Einstein, and whatever it is, it mostly was, before anybody even picked up a pen to write an equation. Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 I am thinking that something working or not working in one's head, having the model fit reality and reality fit the model, is a process that is pretty much contained locally, within a few thousand lyrs at a maximum, and more likely something that is occuring or has occured on the Earth, in the last 4 or 5 thousand years. Nope. Our models seem to work over distance of billions of light years and for billions of years. If two atomic clocks come back from a flight, one in one direction around the Earth and one in the other, and they do not match, and do not match a clock that never left the ground, then there must be a reason. I am still looking for the reason, because time dilation and length contraction do not add up and add back in all the ways I need them to. Have you considered the possibility that it is you who is wrong and not reality? (BTW we are about the same age!) Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 Strange, I understand that numbers and metrics and statistical analysis and all are critical to technology. When small differences add up to big differences the initial conditions have to be adjusted to compensate. The transmitters on the GPS satellites are tuned to a precise frequency to make up for the difference in time and the relative motion between two, distant, moving items. This would be required whether you figured it by relativity equations, or by 2 senses of now figuring, or you could have a self tuning frequency that tuned until a set receiver calculated it was the distance from the satellite that it actually was measured by orbital calculation, to be. The set reciever could send a signal for it to lower the frequency to a longer wavelength if a certain count of peaks resulted in too short a distance calculation, and vice-a-versa. Using any of the three methods would allow technology to work, and none would negate the workability of the other. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 The transmitters on the GPS satellites are tuned to a precise frequency to make up for the difference in time and the relative motion between two, distant, moving items. Almost. They are run at a clock frequency that compensates for most of the difference. This just reduces the amount of correction that needs to be done by the receivers. The entire correction can't be done statically as it depends on a number of variables: the relative speed of satellite and receiver, the difference in height., etc. So the receivers need to use GR to compensate for the difference - they actually use an approximation to reduce the computation required. The receiver also has to take into account the (constantly varying) Doppler effect between it and the satellites. This would be required whether you figured it by relativity equations, or by 2 senses of now figuring Please show how you would do this, in appropriate mathematical detail. You are very fond of making grand statements like this but when challenged to back up your claims it all goes strangely quiet. Why is that, I wonder ... Using any of the three methods would allow technology to work, and none would negate the workability of the other. Why would the makers of GPS receivers (a very cost competitive business) make them unnecessarily complicated, and therefore more expensive? Also, note that it isn't just a matter of varying the clock frequency: the calculations of time and distance (used to do the triangulation to work out the location) also need to be corrected for GR effects. And of course this has to be done (differently) for each of the 4 or more satellites that the receiver tracks. (I used to work on the design of GPS systems) Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 I have considered I am looking at it wrong, but I have also considered I am looking at it OK and the way I am looking at it is not inconsistent with reality. Like the Blind Men and the Elephant story, each was right, and each was talking about the same Elephant, even though one figured the elephant was rather like a wall and another is was rather like a snake, and another it was rather like a leaf... You say our models work over billions of light years distance and over billions of years. But we have no verification of this. We have no observers reporting from distant locations, as to what is going on there, now. And the reports we do get, from billions of lys away are billions of years old, telling us what the universe was like, from that position, billions of years ago. Your sense is that when we see a thing happening in the sky, that is the current thing that is happening in the sky. I absolutely aggree. That is what is happening now, as far as the Earth is concerned, it is those radio waves, those microwaves, those infrared waves, that visible light, those ultraviolet waves, those x-rays, those gamma waves, that are hitting the Earth now, causing things to grow, and bathing beauties to tan, and star observers to plot the position of the stars, and university cosmologists to plot the isotropies of the background microwave radiation. But to a scientist on a planet 45 billion lys from here, whose galaxy is also 13.8 billion years old, and has undergone 2 or 3 generations of star formation, when she looks in the direction of the Milky Way, she does not see the Earth, because this area of the universe is only 380,000 years old to her. We look like cosmic microwave background, to her. That is our position in the universe, was only 380,000 years old when the photons headed in her direction and reaching her today, left. There are two nows. That which is arriving here now. And that which is currently happening, everywhere else. It requires that electromagnetic fluctuations be "on their way" here, from an event at the same time as fluctuations from a previous event at the same location are reaching here. Two locations in space are connected by a constant history of photons. From here and now the universe is complete and satisfactorily connected. From anywhere else the universe is complete, and satisfactorily connected, but since they will order the events of the universe differently and see a different set of events as current, than do we, and since it is commonly agreed that there is only one instance of the Mars rover, even though we know it exists now on our cameras, and it exists now in reality as well, 14 minutes before our cameras report the existence we know there is still only one instance of the rover. Therefore there are two senses of now. That which exists and is 13.8 billion years old, which is everything. And that which is forming the reality on Earth, now. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 And the reports we do get, from billions of lys away are billions of years old, telling us what the universe was like, from that position, billions of years ago. Exactly. Directly contradicting your assertion that it is "a process that is pretty much contained locally, within a few thousand lyrs at a maximum". This would be required whether you figured it by relativity equations, or by 2 senses of now figuring Please show how you would do this, in appropriate mathematical detail. Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 (edited) Strange, Well, first I would have the satelitte relate the clock pulses from its crystal to pulses of a regular pulsar, so that it knew how many pulses of the pulsar and hence how many of its own clock pulses it would take for a signal to get the 50 thousand km or whatever to a known spot on the Earth and back again. I would then send out a frequency whose wavelength would be one meter long according to the figuring. Placing a beep or a blip in the transmission as each pulse of the pulsar is sensed would allow the reciever, to know the time and how many beats until the next beep. The reciever would just have to count the peaks to figure how far away it was from the satelitte. If it counted 25 million peaks in a second it would know it was 25 thousand kms from the satellite. If it counted less it would know it was closer, if it counted more, it would know it was further away. Regards, TAR but the receiver would have to sense the pulsar as well to know when the satelitte put out the beep...so let me think about this It probably took more than 15 minutes to figure out how to use the equations of relativity to set the frequency. Give me a little time to figure how one would do it, using the two senses of now, which does not yet have many equations, figured. edit where quasar should read pulsar Edited August 20, 2015 by tar Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 This makes so little sense, I don't really know where to start. so that it knew how many pulses of the quasar and hence how many of its own clock pulses it would take for a signal to get the 50 thousand km or whatever to a known spot on the Earth and back again How do pulses from a distant galaxy (but I suspect you actually mean pulsar, not quasar) tell it anything about its distance from Earth and the time ilation/length contraction involved? (It is nearer to 20,000 km, by the way.) Placing a beep or a blip in the transmission as each pulse of the quasar is sensed would allow the reciever, to know the time and how many beats until the next beep. Howe would that tell the receiver the time? The reciever would just have to count the peaks to figure how far away it was from the satelitte. If it counted 25 million peaks in a second it would know it was 25 thousand kms from the satellite. If it counted less it would know it was closer, if it counted more, it would know it was further away. How does that work? Do you think frequency changes with distance? And you haven't explained how you compensate for the relativistic changes in time and distance. (I know you like to pretend they don't exist, but unfortunately, they do.) Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 The satellite would be given a particular quasar count. That is that this particular pulsar pulse is pulse number 148,939,984,944. All recievers would figure, according to the count the satellite was on, what count they should be on, should they actually be witnessing the pulsar, (which they are not, but they have it in their programming.) There is a certain time lag between when the reciever should see the pulsar and when the satellite should see the pulsar pulse, but this is regular and known and figurable. So the reciever knows, by the beep, which count the satellite was on when it sent the beep, and it knows how long it has been since it virtually registered that pulse of the pulsar. The time between when it expected to see the pulsar pulse virtually and the time it recieved the beep from the satelitte, should be difference in distance between the light travel path Pulsar-receiver, and the light travel path Pulsar-Satellite-Receiver. This difference could be noted, even without the meter long wavelength count. All you would have to go by, is the lead edge of the signal beep, subtracting any time it takes the satelitte to sense the pulse and put out the beep. What would have to still be properly tested and figured out, is how to set the reciever's virtual pulsar pulse, as in whose here and now is it being set in accordance with, and how what corrections need to be applied as the receiver moves away from that spot. But when you come right down to it, the problem is in syncronizing the clock on the ground, with the clock in the satellite. In relativity this is a problem because the clock is moving and requires and special relativity adjustment to account for its slow tick, and a general relativity adjustment to account for its faster tick according to altitude, and then the other mundane adjustments for doppler shift and such. In the two senses of now, the doppler shift adjustments are still required, but the sychronization of the clocks is done according to how far apart they are. And time itself does not need to be considered variable. It is as constant as the tick of the pulsar. Which arrives at different parts of the universe at different times. Strange, But relativistic effects are both general and special. In one the clock slows because of motion and in the other it speeds up because of altitude. You say these are real, and I will accept that, because you have seen that if you subtract the one and add the other you get a clock ticking at a speed that when creating a frequency based on that speed, it is received by a reciever as a different frequency, based on a uneffected clock. My contention is that the frequency of the signal and its wavelength is no longer affected by the satellite, once it is sent. That is, if the radio signal's wavelength is one meter long, in reference to the receiver, then its one meter long, whether the sender is moving or not, regardless of its clock. It is the sychronization or lack thereof of the clocks, that is the problem, the wavelength can not change, once it is launched. Where and when the time dilation and length contraction is occurring is my question. Regards, TAR Link to comment Share on other sites More sharing options...
Strange Posted August 20, 2015 Share Posted August 20, 2015 The satellite would be given a particular quasar count. That is that this particular pulsar pulse is pulse number 148,939,984,944. You think pulsars transmit numbers!? But when you come right down to it, the problem is in syncronizing the clock on the ground, with the clock in the satellite. That is one part of it. But actually, that is simply done by scanning a range of frequencies until you find the one the satellite is transmitting on. That is the easy part. No relativistic calculations required at all. And time itself does not need to be considered variable. It is as constant as the tick of the pulsar. Which arrives at different parts of the universe at different times. It doesn't just arrive at different times, it will arrive at a different frequency. But relativistic effects are both general and special. Not really. You can account for some effects using just special relativity. Or you can account for all effect using general relativity. You don't have to use both. Link to comment Share on other sites More sharing options...
tar Posted August 20, 2015 Author Share Posted August 20, 2015 If length contraction is relative, then as two items pass each other, both are shortened in terms of the other. If there are moving electromagnetic fields that are present the one item is moving differently, related to the fields than the other. Since the speed of the magnetic and electric field variation or wave is always 186,000 miles per second, and is also 186,000 miles per second when considered the movement of a particle, the lead edge of the wave, and the trail edge of the wave can only be judged as a different frequency, or distance apart, depending on your motion through the wave, or in respect to the wave, as in swimming out to sea or toward shore. Same ocean, but the inward swimmer counts 14 crests in a hundred feet and the outward swimmer 21. Strange, Well wait. If you can account for certain effect using just one, then why bother with the other? And if you can account for certain effects using the other, why bother with the one? And if you can account for certain effects using a different consideration all together, why bother with either? Regards, TAR Strange, I don't know that the pulsar ticks would arrive at different frequencies, if neither the satelitte or the receiver were moving toward or away from the pulsar. Let's say the Pulsar was directly overhead, and so was the Satellite. Why would the two recieve the tick of the pulsar at different frequencies? The satellite is closer to the pulsar and will recieve the tick sooner than the receiver. Regards, TAR Only that you have the satellite's clock ticking slower, would it recieve a different frequency. It has no physical reason to receive a different frequency, only a possible reason to count it differently because it was sped up to compensate for an expected slowdown. Link to comment Share on other sites More sharing options...
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