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Mr. Cooper stumbled upon an interesting feature of relativity theory.
Now, what's all this about? Are you trying to suggest that if I start at rest in Frame A and then race off northwards to be at rest in Frame B instead, when I then send my squares along my east-west-aligned rails which I have taken with me they will behave differently from a rocket launched from rest in Frame A to end up co-moving with my squares which are now racing along between Rails B and B2 such that they have rotated out of alignment with the rails rather than simply taking up the same rhombus shape?
Well, if they do that, they're still demonstrating different physics from what we would see when running squares along between Rails A and A2 which (the rails) are at rest in Frame A - no such rotations or distortions which change the angles of square/rectangle edges occur there. However, in reality they have no choice other than to be length contracted in the NW-SW direction, no matter what kind of rotation you might be adding to them (whether rightly or more likely wrongly).
I see PhysBang hasn't shared his calculations for the arangement of things in Frame A when the rails are moving north instead of co-moving with the rhombus. I wonder if he's bothered to do them at all.
No. What happens is that the rail is no longer oriented in such a way as to produce the kind of motion that you imagine. The composition of velocities and directions is not a simple linear combination.
SR is different than Galilean relativity.
I haven't bothered, since I haven't had the time to work through the Wigner rotation required.
But if you want to make an argument about SR, then I suggest that you use SR rather than just DCR. Because if you just use DCR, then you are a crank.
if you have the rails at rest in Frame B, they'll be aligned perfectly east-west in Frame A,
SR and LET deal with these frames identically when it comes to how things appear in their Euclidean metrics, and I'm doing LET (which SR is forced to conform to, and that means I'm also doing all the relevant parts of SR).
QuoteI haven't bothered, since I haven't had the time to work through the Wigner rotation required.All you need to do is work out how those rails are aligned in the Frame A diagram, and that's no harder than any of the other things you've already worked out. Tip: there's no double boost involved, so you're barking up the wrong tree.
If you can't see that SR has to conform to everything I'm doing here, you're the crank.
Quote from: David Cooper on 15/08/2016 23:26:30if you have the rails at rest in Frame B, they'll be aligned perfectly east-west in Frame A,Well, no. Because of the correction for time, at any moment simultaneous in Frame A the tracks will be at an angle. This is an aspect of the relativity of simultaneity that you just aren't taking into account.
I'm not sure what "LET" is supposed to be, but you are using DCR.
Says the person who can't work out where the rails will be because he can't work out when the rails will be. If you are speaking of trying to sync up moving W-E in a frame moving S-N in order to get a motion that is SW-NE, then you are speaking of a double boost.
Yes, I agree that I am being a crank by refusing to include the time parameter and refusing to do actual transformations and instead just using a series of shortcuts.Oh, wait, I'm not the one refusing to use SR. So who is the crank again?
The angle's perpendicular to the direction of travel when the rails are moving north. You are determined to try to have them co-moving with the rhombus because it's the only thing you can do to keep them aligned with the edges of the rhombus, but even if I allow you to do that, what are you going to do when I send another square NW so that it becomes a rhombus aligned the other way and doesn't fit between your tilted rails? Are you going to have the rails co-moving with that at the same time as they're co-moving with the first rhombus?
LET is Lorentz Ether Theory, as you ought to have learned as part of your training.
The rules of how things behave in the Euclidean metric of a frame and how they appear in other frames is described both by LET and by SR. If the LET approach is used to create diagrams, SR must produce matching diagrams if it isn't to have objects violating the rules. For example, if you want a square at rest in Frame B to be given an eastward shove such that it's co-moving with the rhombus on the rocket, it has to obey the same rules of time dilation and length contraction so as to avoid having a different speed of light operate for it, and that means it must take up the same shape (unless it has somehow rotated, but even then it must have the same amount of length contraction and time dilation applied to it).
You know full well that the rails are not moving east or west at all, but purely north, so there is no double boost. You're turning into a troll - all you're doing now is polluting a thread by dumping your garbage in it.
Yet again you claim I'm not including the time parameter, and yet it's inherent to the diagrams that time is identical for every point shown on them, so you're just repeating a well-worn lie, and that's trolling.
You aren't going to do anything, because you aren't going to work out the time coordinates. Because you are a crank.
No, I have no training in being a crank; I do not know what crazy acronyms a crank is going to use.
And LET has to use time dilation and relative simultaneity between frames of reference just like SR does. You don't get to ignore the rules of LET.
The second boost is to the square, which has to get one boost to match the frame of the tracks and then to follow the tracks. Do you not realize that the square is moving relative to both frames you are imagining?
Cranks love to claim that people asking them for the proper scientific rigor are trolling. I agree that time is inherent in the diagrams, which is why you produce bad diagrams.
You do not have two boosts to pin down what Rails B and B2 are doing as they're moving north through Frame A and only take an acceleration in one direction to get them from rest to relativistic speed in that direction. Likewise, you do not have two boosts to pin down what the square does when you accelerate it from rest to relativistic speed in the direction NE. You can therefore calculate with absolute ease how these items will appear in Frame A diagrams, and to claim that you need two boosts to find the arrangement of either of those rails or the rocket (with the square on it which now appears as a rhombus) is plain wrong. For a square being sent along the rails subsequently, it's another issue, but any rotation that you imagine is magically going to appear on it is going to put it out of alignment with the rails, so again that shows different physics for different frames.
The problem with this reasoning is that it assumes that the square sent off at an angle is equivalent to the square set off along the rails of the second frame. This is not necessarily the case, since no work has been done to show that they are the same; the composition of velocities in SR is not the same as the composition of velocities in Galilean Relativity, no matter how much someone invokes "Euclidean metric" over and over again.
Quote(3) If these rockets are extremely small and they're crewed by tiny robots, we can have them fly over the corners of one of our standard 1m x 1m squares (made of some kind of rigid material, so let's just say it's metal - the atoms of this material are in constant communication through forces which determine their separation). C, D, E and F are now holding station over the corners of one of our squares between Rails B and B2, and it's co-moving with them as they travel directly north. Maybe. You have to establish that this does, in fact, line up this way. The composition of velocities in Galilean relativity suggests that they do, but it is not clear that this happens in SR.
(3) If these rockets are extremely small and they're crewed by tiny robots, we can have them fly over the corners of one of our standard 1m x 1m squares (made of some kind of rigid material, so let's just say it's metal - the atoms of this material are in constant communication through forces which determine their separation). C, D, E and F are now holding station over the corners of one of our squares between Rails B and B2, and it's co-moving with them as they travel directly north.
I've found something I didn't think would ever be possible, but it looks as if there may be a way to pin down an absolute frame of reference.Imagine a disc lying flat with four points marked on the circumference, N, E, S and W (for the four compass directions). We will move the disc northwards in a moment while rotating it clockwise, but let's first spin it up to speed without moving it along through space. I want to spin it until the edge is moving at 0.866c relative to the centre, a speed at which length contraction should act on the edge in such a way as to halve its length. If we also sandwich our rotating disc between two non-rotating discs of equal size we can eliminate all the non-Euclidean SR distractions by imposing a tight Euclidean metric upon our rotating disc in the middle of the sandwich and use that to lay down the law about how the rotating disc must behave in that space.We can see that there is no longer enough material in our rotating disc to fill the whole space between the non-rotating discs, so it must stretch or break. Let's assume it splits and leaves us with gap in it, the gap being much wider the further out you go from the centre as the length contraction becomes more severe. It turns out then that we're going to need to mend our disc once it's been spun up to the target speed so as to fill in the gap, and it's only after that that will we have a complete disc rotating at our target speed. This appears to go against some of the teachings of SR in relation to the behaviour of rotating discs, but it doesn't go against the rules as to how SR works for things moving in straight lines, and we can show that the two things are actually equivalent, which means that many of the existing ideas about how rotating discs behave are wrong.Any rocket following a tangent to our rotating disc at 0.866c must display length contraction to half its rest length, and this must be matched by the material in the edge of the disc as they move side by side for a moment. That means that the edge of the disc must appear length contracted and cannot possibly fill the space all the way round the space demarcated for it by the two non-rotating discs. We can also eliminate most of the change in direction of the material in the disc's edge by using a disc of a diameter measured in billions of lightyears across, which means that the material in the disc's edge will be moving at the same speed and in the same direction as the material in the rocket flying past at a tangent to the disc not merely for an instant, but for many hours with the material in the disc edge and the rocket potentially being side by side and only a micron apart throughout that time - this is more than long enough to rule out any role for accelerations in breaking the normal rules of length contraction and time dilation. So, we can show that a rotating disc cannot behave the way that most SR experts claim it does: it turns out that they have been breaking some of the most fundamental rules of SR.Our next step is to move the whole disc, and we want it to move at 0.866c northwards. By the way, our non rotating discs are transparent, so we can see the rotating disc through them, and our N, E, S, W markers are printed on the non-rotating discs, so N is always the leading point of the discs as they move through space, while S is the point most aft. Once we are moving our disc sandwich along at 0.866c, the material in our rotating disc starts to behave in unexpected ways, bunching up as it moves slowly past point W and whipping back past point E with all length contraction removed there. At point E the material is not moving in the frame of reference we're using as the base for all our measurements, but at point W it is moving northwards at 0.99c and the local length contraction is to 1/7. (To calculate this speed and length contraction at point W, I imagined a rocket moving north at 0.866c and firing a missile ahead at 0.866c from its point of view, and so in our reference frame that works out at 0.99c - that rocket must behave the same way as the material at the edge of the disc where the rocket may travel alongside it for a while as it follows a tangent to the disc at that point.) Our non-rotating discs have length-contraction applying across them exclusively in the NS direction, reducing all measurements running that way to 1/2 of their rest lengths, so the discs' shapes are now elliptical with the NS diameter half the length of the EW diameter. The rotating disc should match that shape if the idea of relativity is correct, but the length contractions on the material of the rotating disc and directions in which it contracts will be different in places, and it's in exploring this that I've found something that I thought couldn't happen.The key thing is what happens at points N and S. The material there is moving at 0.968c (which can be broken down into two vectors: it's moving north at 0.866c, and it's moving sideways at 0.433c) which means that the length contraction will make the material sit four times as close together in its direction of travel as it would do at rest, and this contraction acts at an angle of 63.4 degrees forwards of the EW line. (I worked out the 0.433c figure by thinking about how a light clock aligned EW would work here: the light in it would actually move at 60 degrees ahead of sideways, and that reduces its progress between points E and W to half, so the same halving will apply to anything else moving from E to W and back.) The component of this contraction to 1/4 is greater in the NS direction than the length contraction in the non-rotating discs at points N and S (which is to 1/2), and that's the crucial thing here - this means it must pull the rotating disc in more at N and S than the non-rotating discs, so their shapes will no longer match up in the way they do when the apparatus is not moving along through space - the sandwich filling can no longer fill the whole space between the outer discs. On the non-rotating discs we have length contraction to 1/2 of the rest length all the way from N to S. On the rotating disc we only have that amount of length contraction at the very centre of the line NS: at all other points on the line NS we have more length contraction than that (running in the NS direction). That means that SR must have a theoretically identifiable preferred/absolute frame of referrence.Again we can send a rocket at 0.968c over point N or S at the same angle as the material of the disc there is moving to illustrate that it must contract in exactly the same way in the disc as it does in the rocket, and by giving our disc a huge diameter measured in the billions of lightyears, we can reduce all the pesky accelerations caused by the rotation to such a low level that they can be ignored (while reducing the centrifugal forces to the point of irrelevance at the same time) - the material in the disc can now be thought of as moving in almost perfectly straight lines while we're comparing its behaviour with that of the material in the rockets which are temporarily co-moving with it.
(6) We haven't looked at what our rockets C, D, E and F do when they're given the same movement eastwards as Square B (again without losing the component of their speed taking them northwards). If C, D, E and F have not resynchronised their clocks for Frame B and still have them set for Frame A, they will all accelerate simultaniously from the point of view of Frame A observers and will remain in a rectangle formation,...
...but since these rockets have adjusted their positions to try to make their formation look like a square to themselves, they really ought to have resynchronised their clocks for Frame B. If they've done this, rockets F and E will move off first (from the point of view of Frame A observers), while C and D will move off a moment later, and the result of this will be that Frame A observers will see their formation turn into a parallelogram with its sides parallel to Rails B and B2.
Ah David - I see that you have come across a hurdle.
Under the remit of reference to a Newtonian time, you say that relativity is safe. However... SR is rather contradictory to the underlying philosophy of Newtonian time...
Since all these length contraction maths are still fresh in your mind, try this on for size if you fancy.Dispensing with Newtonian time, create 2 scenarios where both are experiencing different SR time dilations, and state the observation each will make of the other reference frame as time frame dependent and proportional to the difference in rate of time.With time frames missing from the observation of the other reference frame, will it appear as though a length contraction has occurred?
SR and LET are both relativity theories, and any other theory wanting to compete with them will also have to be a relativity theory in order to fit in with how the universe behaves (and how we measure things in it). So long as we can't pin down a preferred frame, relativity survives (even if there is a preferred frame and some other being outside of the universe is able to tell which frame it is). SR attempts to get rid of Newtonian time, but in reality it can't function properly without it as it either generates an infinite number of contradictions or it describes universes in which the future can't be generated out of the past (depending on which version of it you want to use). There are two other models which fix these problems, but in each case they can only do so by adding Newtonian time.
SR attempts to get rid of Newtonian time, but in reality it can't function properly without it as it either generates an infinite number of contradictions or it describes universes in which the future can't be generated out of the past (depending on which version of it you want to use). There are two other models which fix these problems, but in each case they can only do so by adding Newtonian time.
Because you are computer literate, you have of course drawn these lines on your screen. You have 49 lines drawn side by side, the beginnings of these vertical lines form a straight horizontal line at top of screen page, and the ends of these vertical lines form a v shape at bottom of screen page. I now ask you to align your 49 vertical lines so that the ends of the lines form an identical horizontal curve shape at top and bottom of lines. Your 49 vertical lines should now resemble the shape of an ellipse with straight sides.
Now I am going to ask you to make marks on each of these vertical lines from top of line to bottom of line at regular intervals, so that each line resembles a measuring ruler. Although not impossible, it is highly improbable that if you laid a ruler horizontally across these marks, that each of the 49 vertical lines 'ruler' marks would join up one after the other to create a straight horizontal line. The marks would be aligned higgledy piggledy on the horizontal plane... If this has resulted in a visual for you, I can start explaining observational time frame dependency:
Back to the diagram I had you mentally create as a visualisation:The marks you have made at regular intervals on the vertical lines are representative of the time frames of the differing time periods that the lengths of the vertical lines represent. These differing time periods are occurring simultaneously...
Now place your ruler across the horizontal plane and from the top of the first line you drew, draw a horizontal line straight threw to the top of the last line you drew. Repeat the process at each marker down the first line. You will see that every other line of differing lengths markers will be split at intervals that have proportions that are all differing with each different length of line.
I am suggesting that the reference frame of the first vertical line you drew (representing a standard second) will only be able to view a proportion of the reference frames of the longer lines, and that the observable proportion of the reference frames of the other lines is evident in the degree of the splitting these horizontal lines are indicating between the markers you made on the vertical lines. You will be able to repeat the process for each of the vertical lines to work out the observable proportion of the other vertical lines.
With regards to length contraction, would the proportions of the time frames of the reference frame line being observed that are not observable from another reference frames line, amount to the proportion of the expected length contraction as observed from the observing reference frames line?
I had no idea what "Newtonian time" is in this context, despite studying Newton a lot.
According to Magic Schoolbook, "In LET the universe has three space dimensions running under a Newtonian time (which is not considered to be a dimension)..." This is just false, since time is always a dimension.
Magic Schoolbook also says this false thing: "In Einstein's Spacetime, there is no real length contraction, meaning that objects aren't physically contracted by their movement through the fabric of space, and this clearly has to be the case because they can always validly be thought of as being completely stationary as all frames of reference are really equally valid."
Similarly when Magic Schoolbook says this false thing: "He plays a similar trick with time, getting rid of the slowing of moving clocks too. Because all frames of reference are equally valid, a moving clock isn't really moving, so it can't actually be running slow: this too is just an illusion."
In SR, in a frame where a clock is in motion, that clock is legitimately slow.
Here is a great mistake in understanding relativity theory: "The downside to this is that such a universe could never have had its future events generated out of its past events under these rules because many of its events would have failed to mesh together properly during the generation phase (when the block was originally being constructed): a rocket which has taken a shortcut would have been unable to land on a planet which has not taken a shortcut as there wouldn't be a future version of that planet there yet for the rocket to interact with."
One of the important things about relativity theory is the structure of causality. In SR, the speed of light places limits on how things can interact. The only events in the past of a given event are those that could possibly emit light that would reach that event. The only events in the future of a given event are those events that could be reached by light that the given event could emit. The events that reside in this "light cone" are invariant across every inertial reference frame. So there is never a problem of something reaching an event that isn't there. Nothing of this relies on or demands that there is a "block universe", despite the exhortations of the proponents of the block universe model of time. There are many formulations of becoming in time in SR and GR.
One can't simply argue that this is wrong because it doesn't work like other forms of cause and effect.
What follows on the Magic Schoolbook site is, sadly, a weak version of the twin paradox.
Even more sad is the claim, backed up by no citation whatsoever, that people using SR, "simply smuggle in this Newtonian time."
Time and time again people are lead astray by the twin paradox and refuse to understand its resolution. In this case, the author of Magic Schoolbook simply refuses to believe that one could identify one reference frame relative to another without having some overall, preferred reference frame.
This is the kind of things that cranks say, that have an axe to grind and would rather grind that axe than take the time to learn or correct basic mistakes in laying out their diagrams:
"It is quite shocking that such irrational people can hold such sway in science and that they are allowed to drown out anyone who tries to point out the glaring error in their model, but then it must be hard for them to back down even if they can see that they are wrong because they have bought so deeply into what is undoubtedly the most embarrassing mistake in the history of science."
Quote from: PhysBang on 22/08/2016 16:56:31I had no idea what "Newtonian time" is in this context, despite studying Newton a lot.Timey seems to have found a clear definition of it which works for me.
Einstein was very keen to tell people that time is a dimension. I was under the impression that before his theory, it wasn't thought of as a dimension by anyone. I may be wrong, but it was certainly a way that Einstein tried to distinguish his theory from what had come before.
It isn't false: they are always completely uncontracted in their own frame and what you measure does not tell you the truth about the hidden reality. With LET it's radically different: the length contraction is either absolutely real or its merely apparent and not real, all dependent upon whether you're measuring things from at rest in the preferred frame or from some other frame.
If a clock runs faster at rest in one frame than a clock at rest in a different frame, you must have a preferred frame somewhere in the system which has the fastest running clocks. If you don't want a preferred frame, you are not allowed to have any real slowing of clocks for different frames - it must all be an illusion because they must all be running at full speed.
And when you switch frame so that you're co-moving with it, magically it becomes the faster clock. So, is it both slower and faster than the other clock at the same time? Which clock is really running slower?
It's your misunderstanding, not mine. That bit refers specifically to an SR model in which no clocks are allowed to run slow but where they merely appear to do so when viewed from other frames. If you want to have some clocks actually run slower than others though, you need to go for a model with a preferred frame.
There's no point in attacking one model by attacking it on the basis that it is a different model from the one that it is. There are four Spacetime models discussed on my page (called model zero, model one, model two and model three) and it makes no sense to attack model one by demanding that it behave like model two.
Show me how it works without this Newtonian time then. No one else has been able to do so. They say they can write programs to simulate SR which don't cheat, but they always cheat by using Newtonian time to run one frame's clocks at a higher speed than the rest: that's a preferred frame.
My original aim was to prove to myself that SR is valid and then show other people that it works, but I have been unable to do so because it falls so far short.
However, the marks on the vertical lines must be made at uniform intervals on the line. ie, the marks on all of the lines should be same distance apart. There should be more marks on longer lines...
Don't worry if the mark closest to bottom of line doesn't match the end of the line. Its the proportionality of only 1 time frame, ie, from one mark to the next mark, being split by the horizontal lines that we use to match the markers on line 1 and line 49 that matters, and we can read this from the middle of the shape, we don't need to read the ends of lines for this part.
The divisions made between markers on each different length of line will have different proportions to each other...
but the divisions made on a particular line will retain the same proportions of division from top of line to bottom. (bar any messy bottom of line marker issues)
The vertical lines are representing time periods expanding. The markers are representing the time frames of the time period, and the divisions between markers will be representing a; the proportion of that time frame you can observe from line 1 or line 49, and b; the extent that the line, ie: rate of time you are observing, will cause the 'appearance' of a length contraction. ie: the proportion of the time frame you cannot observe from line 1 and line 49.One side of the division will represent a, and the other b.
Some kind of fancy mathematical process of multiplying a or b by the number of spaces between the markers the line has, plus the messy remainder at bottom of line, should give the overall proportionality of a or b for an observation of that particular line, ie: rate of time, from both line 1 and line 49.
Yeah, that one I get. I'm still not sure what you think you mean.
Time is a dimension in the mathematical sense; there is nothing that can be done to change this. Maxwell discussed this and Einstein explicitly built on Maxwell.
This simply more whining that you don't like SR.
There is nothing holy about reference frames in which an object is at rest; these reference frames are no more "real" than frames on which they are moving. They are merely arbitrary choices made for the purposes of assigning coordinates.
With LET, there is a "real" reference frame that has absolutely no effect on the world that we can detect.
If you like that idea, then fine, but please don't mischaracterize it or SR.
QuoteIf a clock runs faster at rest in one frame than a clock at rest in a different frame, you must have a preferred frame somewhere in the system which has the fastest running clocks. If you don't want a preferred frame, you are not allowed to have any real slowing of clocks for different frames - it must all be an illusion because they must all be running at full speed.Again, this is your aesthetic preference. In SR, frames of reference are arbitrary choices of coordinates, not holy metaphysics.
QuoteAnd when you switch frame so that you're co-moving with it, magically it becomes the faster clock. So, is it both slower and faster than the other clock at the same time? Which clock is really running slower?It's not magic, it's the use of a different system of coordinates for description. You might not like that SR allows for different descriptions in different systems of coordinates, but you don't get to force your aesthetic preference on everyone.
And I don't want to have any clocks "actually run slower than others". I am content to accept that it depends on the system of coordinates chosen.
As far as I can tell, none of those models represents SR, so I don't really care.
Again, if any of your models was SR, then it might be less sad.
I really do not understand what you think your claim means. You seem to want some fact of the matter outside of a description in a system of coordinates. In SR, there simply is no such fact of the matter.
Yes, surely the fault lies with the hundreds of physicists, mathematicians, and philosophers who have worked with the theory for over a century.
With Newtonian time it can be treated mathematically as a dimension, but it is only with SR that it became a physical length of anything.
QuoteThere is nothing holy about reference frames in which an object is at rest; these reference frames are no more "real" than frames on which they are moving. They are merely arbitrary choices made for the purposes of assigning coordinates.Indeed - you don't need to tell me that.
QuoteWith LET, there is a "real" reference frame that has absolutely no effect on the world that we can detect.It has an effect in that it enables things to function rationally rather than by magic. That is a big effect.
I'm not mischaracterising it at all - when I say that in SR the true length of something is the length you measure for it when you are co-moving with it, that is the case.
It's called reason. If a clock is running faster than another clock, it cannot also be running slower than it.
It is magic when it involves toleration of a contradiction. If you have a mechanism for something which involves clock A ticking faster than clock B while clock B is ticking faster than clock A, you are irrational and have entered into the realm of magic.
In which case, what you're seeing from any frame is not telling you the truth about how the ticking rates of clocks can be compared.
QuoteYes, surely the fault lies with the hundreds of physicists, mathematicians, and philosophers who have worked with the theory for over a century.It does indeed - they are a self-selected bunch of magical thinkers who tolerate contradictions.
When I ask you to draw vertical lines side by side, (how far apart these vertical lines are is irrelevant, space them at 1cm as you proceed across the page from left to right).
I now extend the time period between the sounding of the first and second bell for line 2. This second vertical line that you have drawn is slight longer than the first. It represents a dilated standard second.
These vertical lines represent the standard second dilating for 24 lines, and then contracting for 24 lines back to the length of a standard second
Looking at line 1 in relation to line 2, we will see that the spaces between the markers on line 2 has been divided by the horizontal line. 1 side of the division will be greater than the other. Line 1 will be able to view the greater part of the division of that time frame, and it will be unable to view the lesser part.
By line 25 we will find that the observable part of the division is much reduced, and that the greater part cannot be observed.
By multiplying the proportions of the division of the space between the markers for any line, by the number of spaces between markers of that line,(the remainder at bottom of line must be proportionally divided and calculated as a point something space.) ...This will give the correct proportionality of what you can and cannot observe of that rate of time.
This dispenses with Newtonian time. All rates of time can be measured relative to a standard second, or indeed any length of second you fancy.
That is mathematically impossible.
It is odd for you to say that, since your entire complaint against SR is that it doesn't have a holy reference frame.
Your "rationally" is not the "rationally" of physics or mathematics. I will stick with the latter two.
No, that is a mischaracterization. If one is to measure the length of an object, then one needs to specify the frame of reference in which one is measuring it. No reference frame, no length. There is no "true length" independent of reference frame. You would like this to be the case (and you make some other conceptual errors), so you choose LET.
QuoteIt's called reason. If a clock is running faster than another clock, it cannot also be running slower than it.And SR holds this to be true. But the rate of a cyclic physical system depends on the system of coordinates. You want a holy clock rate, so you choose to reject SR.
QuoteIt is magic when it involves toleration of a contradiction. If you have a mechanism for something which involves clock A ticking faster than clock B while clock B is ticking faster than clock A, you are irrational and have entered into the realm of magic.And SR has none of these things. Only your desire for holy truth makes you want to create a contradiction where there is none.
On the contrary: because of the theory of relativity, if I know the information from one well-formed frame, I have the information for every well-formed frame (and some that are not well-formed).
There is a long history of physics cranks who want to show the world. They don't produce much, but they spill a lot of ink.
Quote from: PhysBang on 24/08/2016 15:30:25That is mathematically impossible.A second can be represented as a length on a graph, so of course it's possible.
Which is why you will remain irrational. What you still don't get is that the interactive diagram showing models one to three is designed to force people to think about how the future is generated out of the past without doing it by magic.
With a normal Spacetime diagram you don't see this process, but just get the whole thing at once. My diagram with its three modes shows three different ways in which the future can be generated from the past in SR, and the consequences of those three methods.
QuoteNo, that is a mischaracterization. If one is to measure the length of an object, then one needs to specify the frame of reference in which one is measuring it. No reference frame, no length. There is no "true length" independent of reference frame. You would like this to be the case (and you make some other conceptual errors), so you choose LET.Nonsense: there are different interpretations of SR on this point, and you're fully entitled to yours, but it's a trivial issue which I don't give a fig about.
If you have a mechanism in which one frame has clocks that run faster than those of other frames, that is the preferred frame. You can't have more than one frame performing that role at the same location in space.
Some people are blind to contradictions and there appears to be no cure for this, but they are irrational. If the clock of one frame ticks faster than the clock of another while also ticking slower than that clock, that's a contradiction which any rational person should be capable of recognising. Why can't you? What is missing in your thinking toolkit that prevents you from seeing that and from seeing how it is tied to SR?
Quote from: timey on 23/08/2016 23:32:00When I ask you to draw vertical lines side by side, (how far apart these vertical lines are is irrelevant, space them at 1cm as you proceed across the page from left to right).If these lines represent frames of reference, do you have some way of relating them to speeds at which they move relative to each other? I know you said it doesn't need numbers, but these numbers are important in order to get some idea of what's what.QuoteI now extend the time period between the sounding of the first and second bell for line 2. This second vertical line that you have drawn is slight longer than the first. It represents a dilated standard second.How much is slightly longer? I was imagining doubling the length the first time, then the third line would be three times as long as the first, etc., but if that doesn't work, I can't see how there can be any leeway in the proportion that "slightly" represents.QuoteThese vertical lines represent the standard second dilating for 24 lines, and then contracting for 24 lines back to the length of a standard secondIs it necessary to have the 24 lines reducing in length again? Is that just to help draw horizontal lines across the diagram or are they actually meant to be different frames of reference from the first lot?QuoteLooking at line 1 in relation to line 2, we will see that the spaces between the markers on line 2 has been divided by the horizontal line. 1 side of the division will be greater than the other. Line 1 will be able to view the greater part of the division of that time frame, and it will be unable to view the lesser part.Why don't you just simplify this whole thing down to using two lines the same length (a length which we can call L), each as long as the distance between two markers on any of your lines. If we draw these lines side by side, but start the second one slightly higher up the paper, when we draw a line across horizontally from the top of the first line (the lower line) it will cut through the second one and divide it into two lengths, one short (the length of the height difference between the starts of the two lines, so let's call this length M) and one long (whose length will be L - M).For the third line, we can simply use 2M for the shorter length and L - 2M for the longer length. For the fourth line we can use 3M for the shorter length, and L - 3M for the longer legth. At some point, perhaps when we're dealing with L - 20M, 20M might be longer than L, so the whole thing breaks down: this is where we need to know exactly what "slightly longer" means when drawing the 49 lines, or "slightly higher up" with my simplified version when I'm putting in the second line.Even if we get that right though and ensure that L - 24M is a positive number (or zero at worst), there's still a problem with these proportions as they bear no resemblence to the way length contraction and time dilation behave. You might have a series of ratios like these: 25:0, 24:1, 23:2, 22:3, 21:4, 20:5, 19:6, 18:7, 17:8, 16:9, 15:10, 14:11, 13:12, 12:13, etc. (Maybe I should have started at 24 rather than 25, but it's easy to take one away from them all if that's the case.) But what use are these ratios? How would they tell you anything about length contraction or time dilation?QuoteBy line 25 we will find that the observable part of the division is much reduced, and that the greater part cannot be observed.And again, there is nothing that goes unobserved, so what is this a theory of? Why do you want a theory to account for things going unobserved when they don't go unobserved?QuoteBy multiplying the proportions of the division of the space between the markers for any line, by the number of spaces between markers of that line,(the remainder at bottom of line must be proportionally divided and calculated as a point something space.) ...This will give the correct proportionality of what you can and cannot observe of that rate of time.With the numbers I've chosen, there will only be one marker more on the longest line than on the shortest, so we'll be multiplying the proportions listed earlier by 1 plus one of the following: 0/25, 1/25, 2/25, 3/25, 4/25, etc. This means that for the fourth line, I'm taking the 21:4 and multiplying each side by 1 and 4/25, so that's 1.162 times 21 = 24.36, and 1.162 times 4 = 4.64, so we now have 24.36:4.64 (which is of course equal to 21:4 and is therefore a completely unnecessary conversion).You seriously need to put your own numbers to this, doing it the way I have by producing the numbers you want me to get rather than the ones I'm getting perhaps by doing things wrongly. I can't see any way of using this ratio for anything relating to length contraction or time dilation.QuoteThis dispenses with Newtonian time. All rates of time can be measured relative to a standard second, or indeed any length of second you fancy.All I can see is a list of ratios which have any relation to the task. You're going to have to show me the ratios that you've produced, and then you'll need to show how they can be used to calculate time dilation or length contraction for objects moving through a frame of reference at relativistic speed. You also need to explain what you mean by things not being observed because the real universe doesn't hide anything in that way.
Quote from: David Cooper on 24/08/2016 23:44:24Quote from: PhysBang on 24/08/2016 15:30:25That is mathematically impossible.A second can be represented as a length on a graph, so of course it's possible.No, your statement, With Newtonian time it can be treated mathematically as a dimension, but it is only with SR that it became a physical length of anything," is mathematically impossible.
You are right, I don't get it. You have made a choice: you are standing, regardless of what anyone says, against the reasoning of physicists. I am not willing to do this. I wish you all the best and I hope this won't be hard for you. I really, really hope that you ahve someone looking after you.
Like all of your knowledge of SR, you are putting together a half-baked idea of what everyone in history has done based on your limited reading. Many people have made animated SR diagrams. The difference between them and you is that they are using SR and you are not, given that your animated diagrams fail to preserve the same events across different reference frames.
There is no interpretation of SR in which one can have a length without a reference frame. Again, you have a very limited, self-taught knowledge of SR. You seem to hate those people who actually had teachers and you refuse to learn from them and you refuse to read anything more about SR. You have made this choice.
QuoteIf you have a mechanism in which one frame has clocks that run faster than those of other frames, that is the preferred frame. You can't have more than one frame performing that role at the same location in space.You seem to not understand frames of reference at all. There are an infinite number of frames where certain clocks have the same properties of their rate.
And frames are not located in space, space has location by virtue of a frame.
I cannot simply accept your lies about SR. There is no frame in which, "he clock of one frame ticks faster than the clock of another while also ticking slower than that clock." This is your own fabrication.
Like many cranks, you fantasize how SR is based on your limited knowledge and you make a decision about how SR really is and you then reject any person or text that might say otherwise.
This diagram is depicting a mathematical means to a concept I'm calling observational time frame dependency. Although actual numbers can be attributed to this system, what I'm describing is a formula, so it doesn't 'need' them in order to work. I just don't know how to express the formula mathematically.
Perhaps you can now see the possibility that observing that vastly lengthened second from the length of the standard second can result in not being able to actually see very much of that longer second. Resulting in not being able to see all of the rocket travelling at that speed. ie: length contraction
(edit: although these numbers are completly arbitary, the natural divisions would be the length of nano seconds)
This is depicting the ratio of what a reference frame with a length of second as per line 1 will and will not observe of a reference frame that has a length of second as per line 2.
and 'hopefully' can be matched to the maths of the expected length contraction of a reference frame in relative motion as per its expected time dilation.
Nonsense: time can be treated as a time or a distance. Newtonian time treats it as a time while SR treats it as a distance, and indeed it's the only distance that isn't variable within the non-Euclidean geometry where other lengths are different depending on which frame you measure them from.
I'm only standing up for reason. If your SR model can't generate the future out of the past without generating contradictions, it's broken and needs to be modified until it works.
If you're at a Spacetime location and asking questions about what's going on at another Spacetime location while the calculations using one frame of reference are telling you that some event has happened there but the calculations using a different frame of reference are telling you that it hasn't happened yet, one of those accounts is wrong.
Anyone who believes they're both correct is in need of medication.
Where can I find an animation/simulation that does the job in a way you approve of then?
How do they perform the magic trick of avoiding generating contradictions?
Absolute baloney: reference frames in SR give a narrow view of a deeper reality in which objects sit in non-Euclidean space where their true dimensions don't vary in the way they appear to do to us. The maximum lengths we measure for their dimensions (by co-moving with them) are the true lengths - the rest are just warped images of them.
It is SR's fabrication. If you have calculations based on one frame telling you that clock A is ticking faster than clock B while your calculations based on a different frame are telling you that clock B is ticking faster than clock A, they cannot both be telling you the truth. Not all the accounts generated by the analysis based on different frames are valid.
That is why the interactive exam is there - it's designed to force those who are brave enough to take it on to confront the problems and to try to get useful answers from them, and yet what happens? They run away from it and snipe at other things instead because they have no answers.
If they did have answers they would be able to point straight to a site that would show how their SR model can generate the future out of the past without generating contradictions, without a preferred frame, and without event-meshing failures, but there is no such site out there because they have no such model.
Quote from: timey on 25/08/2016 01:16:45This diagram is depicting a mathematical means to a concept I'm calling observational time frame dependency. Although actual numbers can be attributed to this system, what I'm describing is a formula, so it doesn't 'need' them in order to work. I just don't know how to express the formula mathematically.But you must be getting numbers out for the proportions on each line (which I suspect you're doing differently from me). Why not provide a list of those numbers. You must have such a list - just measure them off your diagram with a ruler.QuotePerhaps you can now see the possibility that observing that vastly lengthened second from the length of the standard second can result in not being able to actually see very much of that longer second. Resulting in not being able to see all of the rocket travelling at that speed. ie: length contractionBut one problem there is that we do observe the whole of the longer second - we see the action in slow motion. As for the contraction, that could certainly make it harder to see the detail, but none of the detail is missing - we just need to magnify it more to see it.Quote(edit: although these numbers are completly arbitary, the natural divisions would be the length of nano seconds)Nanoseconds are no less arbitrary.QuoteThis is depicting the ratio of what a reference frame with a length of second as per line 1 will and will not observe of a reference frame that has a length of second as per line 2.What have you actually worked out from this? Can you use it to determine how much length contraction and time dilation there will be when you observe something moving relative to you at 0.866c? Can you get the number 2 or 1/2 out of it? And, if so, can you work out why that answer comes out of it? Does it work for other speeds too? Do you own a calculator capable of doing a square root or are you just doing everything on hope and guesses? If you've found something worthwhile, you need to find out whether it stands up or not, and that means checking the numbers.Quoteand 'hopefully' can be matched to the maths of the expected length contraction of a reference frame in relative motion as per its expected time dilation.Do you have the formula Lorentz uses for calculating length contraction and time dilation? If you don't have a calculator capable of handling roots, would you like someone to give you a list of a range of speeds and their associated length contractions? Feel free to post a list of a hundred speeds and I'll do the maths for you to give you the numbers you need - it'll only take a few minutes to write a little program capable of churning out thousands of them, so you can have as many as you need. You've got to check that your proportions are actually giving you something that matches up to the real numbers of length contraction, because until you've done that you can't possibly know if you've got anything relevant to this business at all.
I'm sorry that you are so limited by whatever you taught yourself and that you refuse to learn anything new. Mathematically, one could always treat time as a length and this was done well before Einstein developed SR. Again, I'm sorry to see you embarrass yourself like this.
And, as everyone working on it has shown for over a century, SR is a deterministic theory for which future events are completely determined by the past. If you think otherwise, then you are making a mistake. You have a significant burden of proof, given the immense amount of study given to the fundamentals of SR.
I would be careful about making that accusation, given that you are the person up against a century of published work and that you are siding with bona fide crackpots against SR.
QuoteWhere can I find an animation/simulation that does the job in a way you approve of then?Have you heard of google?
Quote How do they perform the magic trick of avoiding generating contradictions?They, unlike you, actually use the Lorentz transformations.
This is your spacial David Cooper Relativity theory. You are free to use your own theory, but do not lie to us and say that it is SR.
This is your own, special desire to have a holy frame of reference. Most other people have moved on.
If you ask questions based on falsehoods, then people will point this out.
Why don't you look at any of the major books by Lawrence Sklar, to pick a philosopher of physics out of a hat. It's likely that all of them go into this or at least give a citation. https://en.wikipedia.org/wiki/Lawrence_Sklar#Major_books You imagine that you have to answers, but you are merely poorly read and taught.
On the contrary - I'm one of the few people who can learn and who changes position when I find out I'm wrong about things. You by contrast do not learn even though you keep tripping over things. Here, you are still missing the point and making embarrassing objections to things that really shouldn't be contested. Of course time was often treated like a length before Einstein, and time is often described as short or long just like a length, and people have always talked about lengths of time, but it was with Einstein that it ceased to be metaphorical.
If you weren't too scared to take the interactive exam, you'd find out that there are major problems with how SR is supposed to generate the future out of the past without shedding some of its ideological baggage.
Why are you wasting my time with that pile of irrelevant junk? I want you to show me something that actually shows how the future is generated out of the past in SR without using an external time to control the relative progress on different paths, using nothing other than the time of the "time dimension" and not cheating by using one frame as a preferred frame to govern the rest.
Quote They, unlike you, actually use the Lorentz transformations.That isn't a valid answer because they produce contradictions.
They, unlike you, actually use the Lorentz transformations.
You may not understand SR well enough to recognise this as SR, but it is correct. Objects in SR occupy non-Euclidean space and their dimensions in that space are constant, not shifting with the wind. You are trying to claim that all the Euclidean views of them are providing equally fundamental truths about their shapes, but that is not the case - they are giving warped views of an underlying, unchanging reality.
It is nothing more than my refusal to accept contradictory claims about events. Where one account contradicts another, they cannot both be valid, so attributing equal validity to them is idiotic, and it's that crazy toleration of contradictions that generates the army of cranks and crackpots who attack SR in thousands of different ways, all thinking they may be doing a better job of it than the physicists because the physicists are so clearly barking mad.
It cannot be true that clock A ticks faster than clock B and that clock B ticks faster than clock A.
But they are unable to show falsehoods in the interactive exam.
QuoteWhy don't you look at any of the major books by Lawrence Sklar, to pick a philosopher of physics out of a hat. It's likely that all of them go into this or at least give a citation. https://en.wikipedia.org/wiki/Lawrence_Sklar#Major_books You imagine that you have to answers, but you are merely poorly read and taught.What you don't realise is that the argument I've built on my page came out of discussion with a number of experts on SR, and most of the content of it (including claims which you're objecting to) came directly from them while we collectively built the thought experiment at the centre of it.
Model 1 is also lorentz invarient,
All you can do is throw piles of links at me
Hi Timey,If we were to plot a graph of speeds of travel against the length contraction factor that applies for each speed, we might write speeds along the X-axis and have length contraction factors shown on the Y-axis. The line would run through the point (0,1) and it would look like a horizontal line running right along the graph on the Y=1 line for a very long way out to either side. Eventually it would begin to drift a little from that line, then it would head downwards more quickly until it hits the X-axis where the speed of light is marked. It is possible to create millions of other curves which also pass through (0,1) and which gradually accelerate down to meet the X-axis in the same place, and you will find points all the way along any such line where you can read off what appear to be length contraction values, but these will not be located over the right speeds and they are therefore completely useless for the task.You need to draw a graph of the numbers you're getting off your diagram to see if your graph is the right shape. Until you do that (and you can do it just by checking a few values, so it isn't a massive task), you aren't going to know if your graph is going to be useful or useless. What you appear to have at the moment is a notion rather than a theory, so if you want to turn it into a theory you're going to have to plot your graph. If you're scared to do this because you fear it will destroy your theory, then you're in the wrong game - you seriously need to find out the truth. If the numbers fit, you will certainly have something worth looking at, but the graph I'm getting from applying your method (in my head) appears to be horribly wrong. Perhaps I'm not doing it the right way though, and that's why I need you need to provide your numbers. Without them, no one else can justify putting in the time to explore this any further: these numbers are crucial. You have proportions that you can read off your diagram, but you can find those on any old curve on a graph. How do you read off the frame speed that goes with the contraction values? If you don't know the answer to that, you will never be able to use your diagram to provide useful answers.
I'm surprised that nobody picked up on my earlier comment:"If the occupants of a rocket are observed to be moving about their tasks in slow motion due to time dilation, the rocket must also be moving in slow motion. If the rocket is moving in slow motion it cannot be travelling at the speed causing the time dilation.There is no way to avoid this contradiction"