[Halc (OP)]

In LET there is an absolute frame. In SR there is not, so you are banned from having time dilation - time cannot dilate for a stationary object, and all objects are stationary in SR

David is known for misquoting relativity when it serves his purposes.  This statement is indeed false, and the theory would easily be falsified if it said that.

[There's one serious misinterpretation (red). SR does not state or imply the red portion. It states postulate 1 as: "the laws of physics are the same for all inertial (constant velocity) frames of reference". This translates to, any inertial frame may serve as a reference. A and B qualify as inertial frames, but still have to consider their relative motion in any measurement process.]

I'm on your side on this statement.  B is not moving in the frame of B in the first leg, so it is A whose time is dilated in that frame, and likewise for the return leg in that frame, but David's comment omits those frame references.

The graphic is another 'twin scenario'. It consists of 2 clocks, A and B, moving in separate spaceships to the right. The A path 0 to .4 at .4c and the B path 0 to.8 at .8c.
We examine it from before 1900. The trip time for each is 1.00. If B moved a greater distance than A, in the same time interval, B must have moved faster than A.
Now examine it after 1905, when theory predicts the faster moving clock runs slowest.

It is unclear what you are doing.  How can time be compared if the two ships are in different places?  Such comparisons are very frame dependent.  In some different frame, it is A that is twice as fast as the B ship (both moving to the left).  There is no objective way to compare which clock is ahead of the other.

Bigger note:
Why is this being discussed in this topic?  Open a new one if you want to defend relativity vs. LET or something.  You're not contributing to the discussion going on.

[David Cooper]

[1. That's as observed by a second party. In my inertial frame, light speed in space is always c, regardless of my speed. Light speed is independent of its source, i.e. it does not acquire the speed of the source, which differs from material objects.

That's exactly the point - it doesn't acquire the speed of the source, which means that if the light is coming at you from the north at c relative to you in the first place, it cannot still be coming at you from the north at c relative to you after you've accelerated towards the north. To assert that it is still moving at c relative to you from that direction after the acceleration is to change retrospectively the speed of light relative to you from that direction before the acceleration. That is not legal in mathematics. That is one of the reasons why Minkowski changed STR into a 4D model - he could see that Einstein's original version was mathematically illegal.

2. "the speed for light relative to you in both cases is zero.", as observed by ?

As observed by any competent mathematician who looks at the 4D model.

If you start with two ships sitting a mile apart in frame A with one directly ahead of the other and you accelerate them both identically to 0.866c (in the direction they're pointing), they will still be a mile apart in frame A after the acceleration.

[Agree for frame A. In the ship frames, they will measure their separation as .5 miles.]

No they won't - they'll measure it to be 2 miles. The key point here though is that no contraction is applied in this kind of case.

A mass cannot be accelerated instantly.

Make it near instant and what I said still holds.

Length contraction happens at light speed over microscopic distances (electron cloud), which will be faster than a transfer of energy between particles. The incremental energy transfer will require increasing transit times as it progresses  This is also the reason why a material object cannot be accelerated to light speed. It's NOT due to increasing mass.]

Length contraction doesn't happen by magic - it takes time, and it's done by the particles adjusting to correct their relative positions. This certainly will not happen at the speed of light.

If he chooses 2 ["2. Assume he left E in a ship, knows SR, so concludes he is experiencing time dilation."], he is using an absolute frame mechanism, so he's abandoned STR.

His conclusion is based on 'he knows SR', and there is no absolute frame, which is the basis for the 'relativity principle'.

If there is no absolute frame, there can be no time dilation because there is no mechanism to support time dilation. All the clocks are stationary and cannot tick at different rates.

The following quotes from the 1905 paper by the author of SR:

"Examples of this sort, together with the unsuccessful attempts to discover any motion of the earth relatively to the ``light medium,'' suggest that the phenomena of electrodynamics as well as of mechanics possess no properties corresponding to the idea of absolute rest."

They don't suggest anything of the kind. They simply show that the maths of relativity makes it impossible to pin it down.

"The introduction of a ``luminiferous ether'' will prove to be superfluous inasmuch as the view here to be developed will not require an ``absolutely stationary space'' provided with special properties,"

If you're using a model in which light moves through space at c, that requirement demands an absolute stationary space for your light to travel through at c. Without it, you have no means of controlling its speed through space.

The moving twin's clock runs slow --> slowed by movement through an absolute frame. (If not slowed by this, cannot be slowed.)

The moving twin's clock takes a shortcut into the future --> shortcut only available when moving through an absolute frame. (If not moving, cannot take shortcut.)

[David Cooper]

There is no mixing. It's common knowledge that LET hypothesizes a fixed ether frame that serves as a medium for light  Human thinking desires to interpret new things in terms of older established things (supposedly) understood. Government laws may ban certain activities, theories do not.
Time dilation doesn't require an ether or a fixed frame. The effect results from motion, which alters the distance light must move in any EM process. There is no difference. In SR, events don’t move, which is equivalent to a fixed medium.
So who is confused? Have you read any publications on SR?

I have built models which show that STR doesn't work, and no one in the world has ever built any models in which STR does work - they all cheat by breaking the rules of the model to create the illusion of it working. They bring in an extra kind of time tied to an absolute frame to coordinate the action on different paths and then pretend they haven't done so, but in every single case they have. My models of STR are openly available and have been for a decade. Your side has completely failed to counter them by showing the simplest model that can handle the same action without cheating. A working model of STR is impossible if it works purely on STR's rules. It has to cheat because the model is broken.

The purpose of the 'twin scenario' is to demonstrate that relative motion causes clocks (EM processes) to run slower relative to a reference clock.

And the model doesn't work unless you put an absolute frame into it, so what do you do - you put an absolute frame in and use it to coordinate the action, then you deny that you depend on that absolute frame. Run a simulation of the model to test it properly and you'll see the problem right in front of your eyes - it has an absolute frame which causes the clocks on some paths to run slow. You can't run a simulation without selecting an absolute frame to coordinate the action.

[David Cooper]

In LET there is an absolute frame. In SR there is not, so you are banned from having time dilation - time cannot dilate for a stationary object, and all objects are stationary in SR

David is known for misquoting relativity when it serves his purposes.  This statement is indeed false, and the theory would easily be falsified if it said that.

I'm not misquoting it. I'm telling you what it logically requires when you apply the laws of mathematics to it correctly. You cannot have a clock run slow if it isn't moving, and all objects in STR can be treated as if they aren't moving, so they cannot be running slow. It isn't valid to play games where one of the clocks is still and the other's moving so that the moving one can run slow and then to reanalyse the same event and reverse the assertion about which one's moving in order to make the other clock run slow instead. The only way that mathematics lets you get away with playing that kind of game at all is in the 4D model, but even there you cannot do so in any version with running time (and running causality). Mixing incompatible models is not acceptable.

[David Cooper]

If you look at the diagram, you see that nothing gets this 'newly acquired high speed' ahead of its allowed contraction.  The first atom accelerates far more than the next one, which is essentially still stationary at the first moment no matter how close we put the first atom to the dotted line.

You are now using the caterpillar method for perhaps the first 11 hours of the trip before you get to a point where you have a regular speed distribution in place along the ship.

No idea what you're talking about.

You're moving the atoms at the rear in a manner where they are not at the correct separations for a long time, just like the caterpillar method with an infinite number of waves. You don't have them at the right separations from the ones they're chasing, although they may be at the right separations from the point of view of the member of each pair that's being chased. You only get out of this phase once the correct length contraction on the ship has been achieved.

I've already shown you that it's wrong at the start.

No, you're just asserting it. You've not shown anything. The acceleration of everything is always to the right.  No correction is made for inappropriate contraction, so show me that the contraction doesn't match the speed it is going.  Use numbers...

I gave you numbers, such as 904km/s for the tail applying for 11 hours to get to the right location to conform to the correct length contraction acting on the ship.

Why does it need to be there in 11 hours?

It doesn't. If you want to, it can take a lot longer than that before you get all your atoms in the right places to conform to the required length contraction on the ship, or alternatively you can move the rear atoms at much higher speed than 904km/s to reduce the 11 hour figure - whichever way you do it, this reveals that your atoms at the back are not in the right places for quite some time after the gun. If you want to reduce that time, then you have to use higher and higher speeds for the rear end to make the correction, and the extra energy they're carrying will then need to be scrubbed off to avoid your egg being smashed by a hammer.

The contraction will be a lot more than 36M km.  I think that was perhaps a guess on your part, but we have 27.6 days of the rear moving faster than the front to allow it to reduce the separation of the two, so it does it in 27.6 days, not 11 hours.  No need for anything to move at 904.

I think a simulation's going to be needed to make it clear what's going on and which rules are being bent when. It's just too inefficient trying to discuss it in the air.

Another thing I don't understand.  All atoms everywhere accelerate at a finite c²/D, and decelerate at c²/D' (where D and D' are distances to points in space arbitrarily close to the start event at the rear and beyond the finish event at the nose, respectively).  Since all atoms have finite acceleration and deceleration, they're all treated identically.  No special rules for any point.

The issue is with how you get the ship to conform to the correct amount of length contraction so that there are no stresses on it. As soon as it starts moving, it's too long to be comfortable, and it takes a long time to correct that.

[Halc (OP)]

You are now using the caterpillar method for perhaps the first 11 hours of the trip before you get to a point where you have a regular speed distribution in place along the ship.

No idea what you're talking about.

You're moving the atoms at the rear in a manner where they are not at the correct separations for a long time, just like the caterpillar method with an infinite number of waves.

This is getting old.  They're at correct separations at all times.  They're at the correct separation in the caterpillar method as well, except at the singularity, where separation is bounded but undefined.

You don't have them at the right separations from the ones they're chasing, although they may be at the right separations from the point of view of the member of each pair that's being chased.

If the two atoms are moving at different speeds, you need to integrate the motion between them (which is the same as adding more atoms).  If you will not do this, then the contraction between the two atoms moving at different speeds is bounded by the contractions for the two speeds in question.  If it falls between those two bounds, it is no strain, to the precision of one atom.  As you add atoms, those those bounds approach each other.

I gave you numbers, such as 904km/s for the tail applying for 11 hours to get to the right location to conform to the correct length contraction acting on the ship.

My object never moves that fast.  Show where the separation is wrong at any point along its length at time X.  You're seemingly claiming that it takes 11 hours for one atom to catch up with the nearly stationary one right in front of it.

At what point in time is the separation wrong?  What separation exists (between which two points) at that time, and what should it be if there is to be no strain?  It takes 27.6 days to achieve maximum contraction. That is far longer than 11 hours, so we have plenty of time to move both ends.

I think a simulation's going to be needed to make it clear what's going on and which rules are being bent when. It's just too inefficient trying to discuss it in the air.

Fine.  A simulation will do since it will show the numbers.

The issue is with how you get the ship to conform to the correct amount of length contraction so that there are no stresses on it. As soon as it starts moving, it's too long to be comfortable, and it takes a long time to correct that.

As soon as it starts moving, it is still essentially still stopped everywhere except possibly the tail (depending on how far back that arbitrarily close point is).  It has no contraction except at the hind-most bit.  So it hardly has changed in overall length, and doesn't need to because it is almost entirely still stopped.

We're talking in air as you say.  I see it always being the exact correct length.  It's not like I'm the first one to do the mathematics behind it.  Where do you think that picture came from?
The wave method is another thing.  I've found no sites that describe that sort of motion.  I'm seemingly on my own.

[guest4091]

I have built models which show that STR doesn't work, and no one in the world has ever built any models in which STR does work - they all cheat by breaking the rules of the model to create the illusion of it working. They bring in an extra kind of time tied to an absolute frame to coordinate the action on different paths and then pretend they haven't done so, but in every single case they have. My models of STR are openly available and have been for a decade. Your side has completely failed to counter them by showing the simplest model that can handle the same action without cheating. A working model of STR is impossible if it works purely on STR's rules. It has to cheat because the model is broken.

I have no associations with science organizations. You might submit your work to an established research center to make them aware of your models.

[David Cooper]

I gave you numbers, such as 904km/s for the tail applying for 11 hours to get to the right location to conform to the correct length contraction acting on the ship.

My object never moves that fast.  Show where the separation is wrong at any point along its length at time X.  You're seemingly claiming that it takes 11 hours for one atom to catch up with the nearly stationary one right in front of it.

The 11 hours (which relates to a low-end guess at the amount of contraction over the whole ship once the back end starts moving) is for how long that rear atom has to move at double the speed it's supposed to be moving at before your ship begins to be the right length. It was the right length before the gun when the whole thing was stationary, but as soon as the back end started moving (and not just the back end, because most of the ship instantly starts moving), it's no longer the right length for the contraction which should be applying to it. A simulation would make that clear, but I don't have time to write one for it now and would rather wait until I have built the right tools to be able to build it in a fraction of the time. All I'm trying to do in the meantime is point out places where your ship isn't functioning in accordance with the rules you claim it conforms to. No one will die though if you don't want to recognise that until there's a simulation that makes it plain, so it isn't important.

As soon as it starts moving, it is still essentially still stopped everywhere except possibly the tail (depending on how far back that arbitrarily close point is).  It has no contraction except at the hind-most bit.  So it hardly has changed in overall length, and doesn't need to because it is almost entirely still stopped.

I didn't think it was only the back of the ship that you're moving. You have the back moving at 452 and the front at 0, so I assumed the middle would be doing some speed in between the two and moving at the same seed as that at the finish. When does the middle start and stop moving? Most of the contraction that I'm guessing will apply to the ship will apply towards the back end where the speed is highest, and I still think it will likely involve 11 hours to get the rear atom into the right place with it moving at double speed to get there. That is a significant issue. It may be a small change in overall length, but with your ship spread out across a hundred lightyears, it adds up to a big difference for the sections at the back which span multiple lightyears.

We're talking in air as you say.  I see it always being the exact correct length.  It's not like I'm the first one to do the mathematics behind it.  Where do you think that picture came from?

I would assume that you've taken the idea from a place where it doesn't start with the whole thing stationary and then suddenly have the back end moving at speed with the wrong length contraction on it.

[David Cooper]

I have no associations with science organizations. You might submit your work to an established research center to make them aware of your models.

I considered writing it up for a science journal, but I assumed I would just be ignored due to my lack of the right qualifications and the difficulty of showing things on paper without software, so I've simply communicated directly with people on science forums where I have discussed things with dozens of professional physicists (who are universally irrational when it comes to Einstein's models). However, I looked into it carefully a couple of years ago and found that they don't actually have to see who you are, and you can include software, so it is an option, but I still have every expectation that they simply wouldn't bother to look at it as soon as they see what is claimed, which means preparing a new text for them and versions of the software that don't run in JavaScript or in machine code on top of my own operating system would be a terrible waste of effort, and a costly one in terms of delays to something much more important.

[Halc (OP)]

The 11 hours (which relates to a low-end guess at the amount of contraction over the whole ship once the back end starts moving)

If only the back end is moving at any significant speed, only the back end needs to contract.  The rest is still essentially stopped, and it would be quite the strain if it were to contract at that point already.

You seem to be under the impression that I'm accelerating all parts equally.  You know that you can't do that with a rigid object.

as soon as the back end started moving (and not just the back end, because most of the ship instantly starts moving)

Moving, yes, but still at zero speed to an awful lot of digits.  You've given no time, so I'm taking the moment in time that the rear finishes acceleration and has hit 452 km/s.  At that moment, any point not at the absolute rear is still stationary to arbitrary precision, depending on how close you put D.  At zero speed, it requires zero contraction.

A simulation would make that clear

Indeed it would.

All I'm trying to do in the meantime is point out places where your ship isn't functioning in accordance with the rules you claim it conforms to.

You haven't done that.  You're claiming that a stationary object needs to contract which is just plain wrong. If you think it isn't stationary (to arbitrary precision), then you haven't applied or understood my acceleration curve of c²/D. Only the very rear is moving, and thus only that rear arbitrarily small segment needs to contract a tiny bit, which it does when the rear moves.

I didn't think it was only the back of the ship that you're moving. You have the back moving at 452 and the front at 0, so I assumed the middle would be doing some speed in between the two and moving

As I suspected, you didn't apply my rule at all.  You just assume wrong things.  If we make D a meter behind the object (we can put it a lot closer), then the rear accelerates at c²/D or 9e16 / 1 = 9e16 m/sec² so it takes about 5e-12 seconds to get up to max speed.  The front accelerates at 9e16 / 9.5e17 = 0.095 m/sec or a bit less than 1% of a g.  After that tiny fraction of a second, it is still stopped to over 20 digits.  The middle accelerates at 9e16 / 4.7e17 or a bit less than 2% of a g.  It is also stopped still, not at all moving at some pace half way between the front and rear as you assumed.
How about a point almost at the rear, say 1km in?  That would accelerate at 9e16 / 1000 = 9e13 m/sec² which is some pretty impressive acceleration until you do it for only 5e-12 seconds and find that its speed is 452 m/sec and has moved about a nanometer.  That last km of object has contracted by somewhat more than 1 micron.
The contraction for a km object moving at 452 m/sec is about 1.1 nm, but the object is moving faster than 452 in points between.  So 1 microns is between the bound of 1.1 nm and the 1.1 mm contraction needed if the whole km segment was moving at full speed.  If you want to compute the contraction more accurately than to the millimeter, cut the km into smaller segments and integrate your way through it.  Or put D a bit further back.

When does the middle start and stop moving?

All points start at the same time, and finish at the same time.  Not so with the caterpillar method.
I computed the acceleration rate of the middle above.  That acceleration commences immediately.

I would assume that you've taken the idea from a place where it doesn't start with the whole thing stationary and then suddenly have the back end moving at speed with the wrong length contraction on it.

It assumes the whole thing stationary, and all parts accelerating continuously forever.  I had to make modifications to get it to stop at the desired place.  It doesn't specify how far away the rear is from D.  It doesn't matter.  For the back to move suddenly at speed, it needs to be right next to D (the point at lower left in the picture).

[Halc (OP)]

I am running into all sorts of troubles with the wave method using lots of small waves.
Sure, the thing gets faster with smaller waves, but it also approaches the 55 day solution.
So I went back here in search of an error:

Code: [Select]

...
  while (speedK < speedK10)
  {
    speedC = speedK / 300000.;      // Compute speed as fraction of c
    factorD = sqrt(1 - speedC * speedC);   // Lorentz contraction
    tDmov = kmLH / speedK / SpD;    // Days to move 1 LH at that speed
    tDwav = 36500 * (1. - factorD); // Wave time: 36500 light day ship len
...


Oopsie:  That last line is supposed to compute wave time.  The 36500 converts 100 LY to light days, but it computes distance, not time.  So I'm calculating the time it takes light to move the contraction distance, not the time it takes the object (moving at speedK) to move that distance.

The whole wave thing is back on the floor.  I don't think it is competitive with the original 55 day method.

[Halc (OP)]

A simulation would make that clear

Mind you, I have yet to run any sort of simulation.  I've computed times and answers to some of your questions, but never using a simulation.  The 55.3 day time was a pretty trivial computation and did not involve iteration or simulation.  Just one Lorentz calculation.

[Halc (OP)]

Updated calculation for the single-wave method of moving the object, which involves a singularity.
I corrected the code in post 88 as far as I can tell, but nobody found the first bug, so nobody is probably going to find bugs with this new version.

Code: [Select]

// Time units in hours.
// Input speed in km/sec, but calculations take place as fraction of c
#include <stdio.h>
#include <math.h>
#define SoL 299792.46    // speed of light, km/sec
#define lenLH 876600.    // hours in a century, len of object in LH
int main(int ac, char **av)
{
  double factorD,        // lorentz factor (down)
         speedC,         // speed as fraction of c
         speedK,         // input speed in km/sec
         speedK10, step, // range limit km/sec
         tHmov, tHwav;   // time in hours
  sscanf(*++av, "%lf", &speedK);  // km/sec, but we convert to hrs
  sscanf(*++av, "%lf", &speedK10);
  step = (speedK10-speedK)/10.0;
  speedK10 += step/3;
  while (speedK < speedK10)
  {
    speedC = speedK / SoL;                // Compute speed as fraction of c
    factorD = sqrt(1 - speedC * speedC);  // Lorentz contraction
    tHmov = 1. / speedC;                  // Hours to move 1 LH at that speed
    tHwav = lenLH * (1. - factorD) / speedC; // Hours to move contraction len
    printf("S %.2f T %.9f W %.9f = %.9f \n", // Print in km/sec, days
           speedK, tHmov/24, tHwav/24, (tHmov+tHwav)/24);
    speedK += step;
  }
  return 0;
}
The sweet spot is still near 450 km/sec, same as the continuous acceleration optimal speed.
Interestingly, it takes half the time to move the object at that speed, and the other half of the time for the wave to move the 100 light years.  Here is one run:

Code: [Select]

> caterpillar 350 550
S 350.00 T 35.689578571 W 21.321007134 = 57.010585706
S 370.00 T 33.760412162 W 22.539351300 = 56.299763462
S 390.00 T 32.029108974 W 23.757695620 = 55.786804594
S 410.00 T 30.466713415 W 24.976040097 = 55.442753511
S 430.00 T 29.049656977 W 26.194384738 = 55.244041714
S 450.00 T 27.758561111 W 27.412729556 = 55.171290667
S 470.00 T 26.577345745 W 28.631074559 = 55.208420304
S 490.00 T 25.492556122 W 29.849419750 = 55.341975873
S 510.00 T 24.492848039 W 31.067765143 = 55.560613182
S 530.00 T 23.568589623 W 32.286110742 = 55.854700364
S 550.00 T 22.711550000 W 33.504456555 = 56.216006555Fastest time is at 452.83 km/sec, taking about 55 days and 4 hours, shorter by a smidge than the inertial method.
Perhaps this is because I used a more correct speed of light than the round 300000 figure, but slower light speed would seem to make things a bit slower, not faster.