Known physics defeated by simple puzzle?
in [Relativity]
|
From: Sue... on 7 Apr 2010 12:11 On Apr 7, 11:57 am, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 6, 7:12 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 6 Apr, 18:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Apr 6, 12:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 6 Apr, 17:02, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Apr 6, 10:39 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 6 Apr, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Apr 5, 6:41 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > On 5 Apr, 22:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > On Apr 5, 3:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > I'm happy to make concessions, but I have to be able to ask questions > > > > > > > > > > and get meaningful answers. The ladder in the barn is a prime example. > > > > > > > > > > I'm told "the ladder contracts to fit in the barn". > > > > > > > > > > It contracts to fit the barn in the rest frame of the barn, which is > > > > > > > > > why the ladder makes no marks on the barn doors when the doors are > > > > > > > > > shut at the same time. In the rest frame of the ladder, the ladder > > > > > > > > > does not contract and indeed does not fit inside the barn at all. In > > > > > > > > > the rest frame of the ladder, the reason why there are no marks on the > > > > > > > > > barn doors when they are shut is that they were not shut at the same > > > > > > > > > time in this frame. > > > > > > > > > This logic is easily defeated Paul, because if we contracted the > > > > > > > > ladder's length *just* enough so that it marked the door in the barn > > > > > > > > frame (in other words, the ladder has contracted just enough to manage > > > > > > > > an interference fit with both doors shut), then this cannot be > > > > > > > > accounted for in the ladder frame (because, in the ladder frame, if > > > > > > > > the ladder is *even larger* relative to the barn than when it started, > > > > > > > > then the ladder could not possibly mark the doors in the same way). > > > > > > > > I'm not sure what the fuss is. The observation is that the doors are > > > > > > > shut and open without striking the pole, and this is true in both > > > > > > > reference frames examined (as well as any other inertial reference > > > > > > > frame). The account in the ladder frame is, however, not because the > > > > > > > ladder fits inside the barn. It is exactly as I described above. Why > > > > > > > is this difficult? > > > > > > > It isn't difficult for me. I can explain it, in its entirety, in terms > > > > > > of a "visual effect" and the careful timing of the doors. It's other > > > > > > people here who keep insisting that it is not a visual effect, and > > > > > > hence the fuss. > > > > > > I don't believe it's a "visual effect" at all. The doors are closed > > > > > and opened by a common trigger, electronically. > > > > > > Is it your claim that the doors are "really" closed and opened > > > > > simultaneously, but they only visually appear to close and open > > > > > nonsimultaneously in the ladder frame? Then how does the 80 foot > > > > > ladder fit into the 40 ft barn without the doors striking the ladder, > > > > > if the doors are "really" closed simultaneously? > > > > > I would contend that the ladder never does fit, and even though it > > > > would *appear* observationally to be small enough to fit, any attempt > > > > to actually shut the doors while the ladder is inside will produce > > > > catastrophe. > > > > This is inconsistent with experiment. > > > We've had this one before Paul. No experiment of this kind (i.e. > > trying to confine objects moving at relativistic speeds) has ever been > > performed. I even gave sources last time for this statement. > > That is simply not true. At RHIC, for example, where nucleus-nucleus > collisions are done, the density of the quarks and gluons goes up > precisely because of this Lorentz contraction. The nucleus is > "squashed" and the density goes up. This is essential to both the > design and the operation of this multimillion dollar facility. Nuclear reactions are not inertial motion. Sue... > > Furthermore, secondary particle emission from particle collisions have > been done in both fixed target and collider facilities. Under both > circumstances, relativity predicts the uniform distribution of those > secondaries according to a variable called rapidity. In experiments, > calorimeters are then arranged around the collision point and > segmented in regular rapidity bins. Naturally, because the two > experiments are viewing the same collisions from two different > reference frames, the length binning for equal rapidity bins is > considerably different, precisely because of Lorentz contraction. > Thus, the distribution by rapidity, as shown by the particle deposits > in the calorimeter, is an indirect but definitive check on Lorentz > contraction. Experimentally, the match-up is exquisite. > > It's unfortunate that your web references are not accurate on this > score, and have led you to the impression that Lorentz contraction is > all hypothetical and without experimental support. I will just > attribute this to the lack of depth of experimental information you've > been able to lay your hands on. > > > > > > As I mentioned before, the first thing one must do in the case of an > > > observational science, is to not deny what is actually seen in > > > experiment, just because you do not immediately understand how that > > > outcome could arise. > > > No one is denying what is seen. The ladder and barn paradox has never > > been "seen". We have merely reasoned, using the tenets of SR, that > > this is what we *would* see, if we were able to perform an experiment. > > And equivalent experiments, those that demonstrate this effect, have > indeed been done. > > > But as I've said previously, even if this *is* what we would "see", > > seeing is not necessarily believing. > > And this is what I'm telling you is a bad policy in science. If > experiment comes in conflict with common sense -- that is, if what you > see is in conflict with what you understand -- then it is common sense > that should properly give way. I understand fully that you say you > just don't operate that way, and don't see why you should have to. > > > > > Incidentally, I seem to remember Terrell ruled out any real > > observation of this contraction. > > > > As indicated above, the doors are closed and then opened by a single > > > trigger and equal-length, exchangeable cables. There is no catastrophe > > > observed. > > > You're asserting this. There is no experimental evidence of this being > > the case. > > You are wrong.
From: PD on 7 Apr 2010 12:19 On Apr 7, 11:11 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > On Apr 7, 11:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Apr 6, 7:12 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 6 Apr, 18:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Apr 6, 12:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > On 6 Apr, 17:02, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Apr 6, 10:39 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > On 6 Apr, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Apr 5, 6:41 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > On 5 Apr, 22:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > On Apr 5, 3:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > I'm happy to make concessions, but I have to be able to ask questions > > > > > > > > > > > and get meaningful answers. The ladder in the barn is a prime example. > > > > > > > > > > > I'm told "the ladder contracts to fit in the barn". > > > > > > > > > > > It contracts to fit the barn in the rest frame of the barn, which is > > > > > > > > > > why the ladder makes no marks on the barn doors when the doors are > > > > > > > > > > shut at the same time. In the rest frame of the ladder, the ladder > > > > > > > > > > does not contract and indeed does not fit inside the barn at all. In > > > > > > > > > > the rest frame of the ladder, the reason why there are no marks on the > > > > > > > > > > barn doors when they are shut is that they were not shut at the same > > > > > > > > > > time in this frame. > > > > > > > > > > This logic is easily defeated Paul, because if we contracted the > > > > > > > > > ladder's length *just* enough so that it marked the door in the barn > > > > > > > > > frame (in other words, the ladder has contracted just enough to manage > > > > > > > > > an interference fit with both doors shut), then this cannot be > > > > > > > > > accounted for in the ladder frame (because, in the ladder frame, if > > > > > > > > > the ladder is *even larger* relative to the barn than when it started, > > > > > > > > > then the ladder could not possibly mark the doors in the same way). > > > > > > > > > I'm not sure what the fuss is. The observation is that the doors are > > > > > > > > shut and open without striking the pole, and this is true in both > > > > > > > > reference frames examined (as well as any other inertial reference > > > > > > > > frame). The account in the ladder frame is, however, not because the > > > > > > > > ladder fits inside the barn. It is exactly as I described above. Why > > > > > > > > is this difficult? > > > > > > > > It isn't difficult for me. I can explain it, in its entirety, in terms > > > > > > > of a "visual effect" and the careful timing of the doors. It's other > > > > > > > people here who keep insisting that it is not a visual effect, and > > > > > > > hence the fuss. > > > > > > > I don't believe it's a "visual effect" at all. The doors are closed > > > > > > and opened by a common trigger, electronically. > > > > > > > Is it your claim that the doors are "really" closed and opened > > > > > > simultaneously, but they only visually appear to close and open > > > > > > nonsimultaneously in the ladder frame? Then how does the 80 foot > > > > > > ladder fit into the 40 ft barn without the doors striking the ladder, > > > > > > if the doors are "really" closed simultaneously? > > > > > > I would contend that the ladder never does fit, and even though it > > > > > would *appear* observationally to be small enough to fit, any attempt > > > > > to actually shut the doors while the ladder is inside will produce > > > > > catastrophe. > > > > > This is inconsistent with experiment. > > > > We've had this one before Paul. No experiment of this kind (i.e. > > > trying to confine objects moving at relativistic speeds) has ever been > > > performed. I even gave sources last time for this statement. > > > That is simply not true. At RHIC, for example, where nucleus-nucleus > > collisions are done, the density of the quarks and gluons goes up > > precisely because of this Lorentz contraction. The nucleus is > > "squashed" and the density goes up. This is essential to both the > > design and the operation of this multimillion dollar facility. > > Nuclear reactions are not inertial motion. Looking at the same interactions from two different reference frames in relative inertial motion with respect to each other is what this is about. Even your poor grip on the principle of relativity should take hold here. If not, then your grip on the principle of relativity is even poorer than I thought. > > Sue... > > > > > Furthermore, secondary particle emission from particle collisions have > > been done in both fixed target and collider facilities. Under both > > circumstances, relativity predicts the uniform distribution of those > > secondaries according to a variable called rapidity. In experiments, > > calorimeters are then arranged around the collision point and > > segmented in regular rapidity bins. Naturally, because the two > > experiments are viewing the same collisions from two different > > reference frames, the length binning for equal rapidity bins is > > considerably different, precisely because of Lorentz contraction. > > Thus, the distribution by rapidity, as shown by the particle deposits > > in the calorimeter, is an indirect but definitive check on Lorentz > > contraction. Experimentally, the match-up is exquisite. > > > It's unfortunate that your web references are not accurate on this > > score, and have led you to the impression that Lorentz contraction is > > all hypothetical and without experimental support. I will just > > attribute this to the lack of depth of experimental information you've > > been able to lay your hands on. > > > > > As I mentioned before, the first thing one must do in the case of an > > > > observational science, is to not deny what is actually seen in > > > > experiment, just because you do not immediately understand how that > > > > outcome could arise. > > > > No one is denying what is seen. The ladder and barn paradox has never > > > been "seen". We have merely reasoned, using the tenets of SR, that > > > this is what we *would* see, if we were able to perform an experiment.. > > > And equivalent experiments, those that demonstrate this effect, have > > indeed been done. > > > > But as I've said previously, even if this *is* what we would "see", > > > seeing is not necessarily believing. > > > And this is what I'm telling you is a bad policy in science. If > > experiment comes in conflict with common sense -- that is, if what you > > see is in conflict with what you understand -- then it is common sense > > that should properly give way. I understand fully that you say you > > just don't operate that way, and don't see why you should have to. > > > > Incidentally, I seem to remember Terrell ruled out any real > > > observation of this contraction. > > > > > As indicated above, the doors are closed and then opened by a single > > > > trigger and equal-length, exchangeable cables. There is no catastrophe > > > > observed. > > > > You're asserting this. There is no experimental evidence of this being > > > the case. > > > You are wrong. > >
From: Sue... on 7 Apr 2010 12:31 On Apr 7, 12:19 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 7, 11:11 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > > On Apr 7, 11:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Apr 6, 7:12 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 6 Apr, 18:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Apr 6, 12:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 6 Apr, 17:02, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Apr 6, 10:39 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > On 6 Apr, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > On Apr 5, 6:41 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > On 5 Apr, 22:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > On Apr 5, 3:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > > I'm happy to make concessions, but I have to be able to ask questions > > > > > > > > > > > > and get meaningful answers. The ladder in the barn is a prime example. > > > > > > > > > > > > I'm told "the ladder contracts to fit in the barn". > > > > > > > > > > > > It contracts to fit the barn in the rest frame of the barn, which is > > > > > > > > > > > why the ladder makes no marks on the barn doors when the doors are > > > > > > > > > > > shut at the same time. In the rest frame of the ladder, the ladder > > > > > > > > > > > does not contract and indeed does not fit inside the barn at all. In > > > > > > > > > > > the rest frame of the ladder, the reason why there are no marks on the > > > > > > > > > > > barn doors when they are shut is that they were not shut at the same > > > > > > > > > > > time in this frame. > > > > > > > > > > > This logic is easily defeated Paul, because if we contracted the > > > > > > > > > > ladder's length *just* enough so that it marked the door in the barn > > > > > > > > > > frame (in other words, the ladder has contracted just enough to manage > > > > > > > > > > an interference fit with both doors shut), then this cannot be > > > > > > > > > > accounted for in the ladder frame (because, in the ladder frame, if > > > > > > > > > > the ladder is *even larger* relative to the barn than when it started, > > > > > > > > > > then the ladder could not possibly mark the doors in the same way). > > > > > > > > > > I'm not sure what the fuss is. The observation is that the doors are > > > > > > > > > shut and open without striking the pole, and this is true in both > > > > > > > > > reference frames examined (as well as any other inertial reference > > > > > > > > > frame). The account in the ladder frame is, however, not because the > > > > > > > > > ladder fits inside the barn. It is exactly as I described above. Why > > > > > > > > > is this difficult? > > > > > > > > > It isn't difficult for me. I can explain it, in its entirety, in terms > > > > > > > > of a "visual effect" and the careful timing of the doors. It's other > > > > > > > > people here who keep insisting that it is not a visual effect, and > > > > > > > > hence the fuss. > > > > > > > > I don't believe it's a "visual effect" at all. The doors are closed > > > > > > > and opened by a common trigger, electronically. > > > > > > > > Is it your claim that the doors are "really" closed and opened > > > > > > > simultaneously, but they only visually appear to close and open > > > > > > > nonsimultaneously in the ladder frame? Then how does the 80 foot > > > > > > > ladder fit into the 40 ft barn without the doors striking the ladder, > > > > > > > if the doors are "really" closed simultaneously? > > > > > > > I would contend that the ladder never does fit, and even though it > > > > > > would *appear* observationally to be small enough to fit, any attempt > > > > > > to actually shut the doors while the ladder is inside will produce > > > > > > catastrophe. > > > > > > This is inconsistent with experiment. > > > > > We've had this one before Paul. No experiment of this kind (i.e. > > > > trying to confine objects moving at relativistic speeds) has ever been > > > > performed. I even gave sources last time for this statement. > > > > That is simply not true. At RHIC, for example, where nucleus-nucleus > > > collisions are done, the density of the quarks and gluons goes up > > > precisely because of this Lorentz contraction. The nucleus is > > > "squashed" and the density goes up. This is essential to both the > > > design and the operation of this multimillion dollar facility. > > > Nuclear reactions are not inertial motion. > > Looking at the same interactions from two different reference frames > in relative inertial motion with respect to each other is what this is > about. Charged particles are not in inertial motion. Lorentz force? The big magents? Sue... Even your poor grip on the principle of relativity should take > hold here. If not, then your grip on the principle of relativity is > even poorer than I thought. > > > > > Sue... > > > > Furthermore, secondary particle emission from particle collisions have > > > been done in both fixed target and collider facilities. Under both > > > circumstances, relativity predicts the uniform distribution of those > > > secondaries according to a variable called rapidity. In experiments, > > > calorimeters are then arranged around the collision point and > > > segmented in regular rapidity bins. Naturally, because the two > > > experiments are viewing the same collisions from two different > > > reference frames, the length binning for equal rapidity bins is > > > considerably different, precisely because of Lorentz contraction. > > > Thus, the distribution by rapidity, as shown by the particle deposits > > > in the calorimeter, is an indirect but definitive check on Lorentz > > > contraction. Experimentally, the match-up is exquisite. > > > > It's unfortunate that your web references are not accurate on this > > > score, and have led you to the impression that Lorentz contraction is > > > all hypothetical and without experimental support. I will just > > > attribute this to the lack of depth of experimental information you've > > > been able to lay your hands on. > > > > > > As I mentioned before, the first thing one must do in the case of an > > > > > observational science, is to not deny what is actually seen in > > > > > experiment, just because you do not immediately understand how that > > > > > outcome could arise. > > > > > No one is denying what is seen. The ladder and barn paradox has never > > > > been "seen". We have merely reasoned, using the tenets of SR, that > > > > this is what we *would* see, if we were able to perform an experiment. > > > > And equivalent experiments, those that demonstrate this effect, have > > > indeed been done. > > > > > But as I've said previously, even if this *is* what we would "see", > > > > seeing is not necessarily believing. > > > > And this is what I'm telling you is a bad policy in science. If > > > experiment comes in conflict with common sense -- that is, if what you > > > see is in conflict with what you understand -- then it is common sense > > > that should properly give way. I understand fully that you say you > > > just don't operate that way, and don't see why you should have to. > > > > > Incidentally, I seem to remember Terrell ruled out any real > > > > observation of this contraction. > > > > > > As indicated above, the doors are closed and then opened by a single > > > > > trigger and equal-length, exchangeable cables. There is no catastrophe > > > > > observed. > > > > > You're asserting this. There is no experimental evidence of this being > > > > the case. > > > > You are wrong. > >
From: PD on 7 Apr 2010 12:42 On Apr 7, 11:31 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > On Apr 7, 12:19 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Apr 7, 11:11 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > On Apr 7, 11:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Apr 6, 7:12 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > On 6 Apr, 18:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Apr 6, 12:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > On 6 Apr, 17:02, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Apr 6, 10:39 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > On 6 Apr, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > On Apr 5, 6:41 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > On 5 Apr, 22:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > > On Apr 5, 3:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > > > I'm happy to make concessions, but I have to be able to ask questions > > > > > > > > > > > > > and get meaningful answers. The ladder in the barn is a prime example. > > > > > > > > > > > > > I'm told "the ladder contracts to fit in the barn". > > > > > > > > > > > > > It contracts to fit the barn in the rest frame of the barn, which is > > > > > > > > > > > > why the ladder makes no marks on the barn doors when the doors are > > > > > > > > > > > > shut at the same time. In the rest frame of the ladder, the ladder > > > > > > > > > > > > does not contract and indeed does not fit inside the barn at all. In > > > > > > > > > > > > the rest frame of the ladder, the reason why there are no marks on the > > > > > > > > > > > > barn doors when they are shut is that they were not shut at the same > > > > > > > > > > > > time in this frame. > > > > > > > > > > > > This logic is easily defeated Paul, because if we contracted the > > > > > > > > > > > ladder's length *just* enough so that it marked the door in the barn > > > > > > > > > > > frame (in other words, the ladder has contracted just enough to manage > > > > > > > > > > > an interference fit with both doors shut), then this cannot be > > > > > > > > > > > accounted for in the ladder frame (because, in the ladder frame, if > > > > > > > > > > > the ladder is *even larger* relative to the barn than when it started, > > > > > > > > > > > then the ladder could not possibly mark the doors in the same way). > > > > > > > > > > > I'm not sure what the fuss is. The observation is that the doors are > > > > > > > > > > shut and open without striking the pole, and this is true in both > > > > > > > > > > reference frames examined (as well as any other inertial reference > > > > > > > > > > frame). The account in the ladder frame is, however, not because the > > > > > > > > > > ladder fits inside the barn. It is exactly as I described above. Why > > > > > > > > > > is this difficult? > > > > > > > > > > It isn't difficult for me. I can explain it, in its entirety, in terms > > > > > > > > > of a "visual effect" and the careful timing of the doors. It's other > > > > > > > > > people here who keep insisting that it is not a visual effect, and > > > > > > > > > hence the fuss. > > > > > > > > > I don't believe it's a "visual effect" at all. The doors are closed > > > > > > > > and opened by a common trigger, electronically. > > > > > > > > > Is it your claim that the doors are "really" closed and opened > > > > > > > > simultaneously, but they only visually appear to close and open > > > > > > > > nonsimultaneously in the ladder frame? Then how does the 80 foot > > > > > > > > ladder fit into the 40 ft barn without the doors striking the ladder, > > > > > > > > if the doors are "really" closed simultaneously? > > > > > > > > I would contend that the ladder never does fit, and even though it > > > > > > > would *appear* observationally to be small enough to fit, any attempt > > > > > > > to actually shut the doors while the ladder is inside will produce > > > > > > > catastrophe. > > > > > > > This is inconsistent with experiment. > > > > > > We've had this one before Paul. No experiment of this kind (i.e. > > > > > trying to confine objects moving at relativistic speeds) has ever been > > > > > performed. I even gave sources last time for this statement. > > > > > That is simply not true. At RHIC, for example, where nucleus-nucleus > > > > collisions are done, the density of the quarks and gluons goes up > > > > precisely because of this Lorentz contraction. The nucleus is > > > > "squashed" and the density goes up. This is essential to both the > > > > design and the operation of this multimillion dollar facility. > > > > Nuclear reactions are not inertial motion. > > > Looking at the same interactions from two different reference frames > > in relative inertial motion with respect to each other is what this is > > about. > > Charged particles are not in inertial motion. > Lorentz force? The big magents? There are no steering magnets for a number of meters surrounding the intersection region. They would pose a small problem for the secondaries leaving the collision to actually get to the detectors, you see. Good grief. > > Sue... > > Even your poor grip on the principle of relativity should take > > > hold here. If not, then your grip on the principle of relativity is > > even poorer than I thought. > > > > Sue... > > > > > Furthermore, secondary particle emission from particle collisions have > > > > been done in both fixed target and collider facilities. Under both > > > > circumstances, relativity predicts the uniform distribution of those > > > > secondaries according to a variable called rapidity. In experiments, > > > > calorimeters are then arranged around the collision point and > > > > segmented in regular rapidity bins. Naturally, because the two > > > > experiments are viewing the same collisions from two different > > > > reference frames, the length binning for equal rapidity bins is > > > > considerably different, precisely because of Lorentz contraction. > > > > Thus, the distribution by rapidity, as shown by the particle deposits > > > > in the calorimeter, is an indirect but definitive check on Lorentz > > > > contraction. Experimentally, the match-up is exquisite. > > > > > It's unfortunate that your web references are not accurate on this > > > > score, and have led you to the impression that Lorentz contraction is > > > > all hypothetical and without experimental support. I will just > > > > attribute this to the lack of depth of experimental information you've > > > > been able to lay your hands on. > > > > > > > As I mentioned before, the first thing one must do in the case of an > > > > > > observational science, is to not deny what is actually seen in > > > > > > experiment, just because you do not immediately understand how that > > > > > > outcome could arise. > > > > > > No one is denying what is seen. The ladder and barn paradox has never > > > > > been "seen". We have merely reasoned, using the tenets of SR, that > > > > > this is what we *would* see, if we were able to perform an experiment. > > > > > And equivalent experiments, those that demonstrate this effect, have > > > > indeed been done. > > > > > > But as I've said previously, even if this *is* what we would "see", > > > > > seeing is not necessarily believing. > > > > > And this is what I'm telling you is a bad policy in science. If > > > > experiment comes in conflict with common sense -- that is, if what you > > > > see is in conflict with what you understand -- then it is common sense > > > > that should properly give way. I understand fully that you say you > > > > just don't operate that way, and don't see why you should have to. > > > > > > Incidentally, I seem to remember Terrell ruled out any real > > > > > observation of this contraction. > > > > > > > As indicated above, the doors are closed and then opened by a single > > > > > > trigger and equal-length, exchangeable cables. There is no catastrophe > > > > > > observed. > > > > > > You're asserting this. There is no experimental evidence of this being > > > > > the case. > > > > > You are wrong. > >
From: Sue... on 7 Apr 2010 13:06
On Apr 7, 12:42 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Apr 7, 11:31 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > > On Apr 7, 12:19 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Apr 7, 11:11 am, "Sue..." <suzysewns...(a)yahoo.com.au> wrote: > > > > > On Apr 7, 11:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Apr 6, 7:12 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 6 Apr, 18:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Apr 6, 12:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > On 6 Apr, 17:02, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > On Apr 6, 10:39 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > On 6 Apr, 16:28, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > On Apr 5, 6:41 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > > On 5 Apr, 22:10, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > > > On Apr 5, 3:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > > > > > > I'm happy to make concessions, but I have to be able to ask questions > > > > > > > > > > > > > > and get meaningful answers. The ladder in the barn is a prime example. > > > > > > > > > > > > > > I'm told "the ladder contracts to fit in the barn". > > > > > > > > > > > > > > It contracts to fit the barn in the rest frame of the barn, which is > > > > > > > > > > > > > why the ladder makes no marks on the barn doors when the doors are > > > > > > > > > > > > > shut at the same time. In the rest frame of the ladder, the ladder > > > > > > > > > > > > > does not contract and indeed does not fit inside the barn at all. In > > > > > > > > > > > > > the rest frame of the ladder, the reason why there are no marks on the > > > > > > > > > > > > > barn doors when they are shut is that they were not shut at the same > > > > > > > > > > > > > time in this frame. > > > > > > > > > > > > > This logic is easily defeated Paul, because if we contracted the > > > > > > > > > > > > ladder's length *just* enough so that it marked the door in the barn > > > > > > > > > > > > frame (in other words, the ladder has contracted just enough to manage > > > > > > > > > > > > an interference fit with both doors shut), then this cannot be > > > > > > > > > > > > accounted for in the ladder frame (because, in the ladder frame, if > > > > > > > > > > > > the ladder is *even larger* relative to the barn than when it started, > > > > > > > > > > > > then the ladder could not possibly mark the doors in the same way). > > > > > > > > > > > > I'm not sure what the fuss is. The observation is that the doors are > > > > > > > > > > > shut and open without striking the pole, and this is true in both > > > > > > > > > > > reference frames examined (as well as any other inertial reference > > > > > > > > > > > frame). The account in the ladder frame is, however, not because the > > > > > > > > > > > ladder fits inside the barn. It is exactly as I described above. Why > > > > > > > > > > > is this difficult? > > > > > > > > > > > It isn't difficult for me. I can explain it, in its entirety, in terms > > > > > > > > > > of a "visual effect" and the careful timing of the doors. It's other > > > > > > > > > > people here who keep insisting that it is not a visual effect, and > > > > > > > > > > hence the fuss. > > > > > > > > > > I don't believe it's a "visual effect" at all. The doors are closed > > > > > > > > > and opened by a common trigger, electronically. > > > > > > > > > > Is it your claim that the doors are "really" closed and opened > > > > > > > > > simultaneously, but they only visually appear to close and open > > > > > > > > > nonsimultaneously in the ladder frame? Then how does the 80 foot > > > > > > > > > ladder fit into the 40 ft barn without the doors striking the ladder, > > > > > > > > > if the doors are "really" closed simultaneously? > > > > > > > > > I would contend that the ladder never does fit, and even though it > > > > > > > > would *appear* observationally to be small enough to fit, any attempt > > > > > > > > to actually shut the doors while the ladder is inside will produce > > > > > > > > catastrophe. > > > > > > > > This is inconsistent with experiment. > > > > > > > We've had this one before Paul. No experiment of this kind (i.e.. > > > > > > trying to confine objects moving at relativistic speeds) has ever been > > > > > > performed. I even gave sources last time for this statement. > > > > > > That is simply not true. At RHIC, for example, where nucleus-nucleus > > > > > collisions are done, the density of the quarks and gluons goes up > > > > > precisely because of this Lorentz contraction. The nucleus is > > > > > "squashed" and the density goes up. This is essential to both the > > > > > design and the operation of this multimillion dollar facility. > > > > > Nuclear reactions are not inertial motion. > > > > Looking at the same interactions from two different reference frames > > > in relative inertial motion with respect to each other is what this is > > > about. > > > Charged particles are not in inertial motion. > > Lorentz force? The big magents? > > There are no steering magnets for a number of meters surrounding the > intersection region. They would pose a small problem for the > secondaries leaving the collision to actually get to the detectors, > you see. Good grief. OK That seem plausible. You ane not making the same argument "Inertial" is, which is more like LET. The particles will "see" each other as shorter but they avoid no collision as LET claims for moving barn doors. Sue... > > > > > Sue... > > > Even your poor grip on the principle of relativity should take > > > > hold here. If not, then your grip on the principle of relativity is > > > even poorer than I thought. > > > > > Sue... > > > > > > Furthermore, secondary particle emission from particle collisions have > > > > > been done in both fixed target and collider facilities. Under both > > > > > circumstances, relativity predicts the uniform distribution of those > > > > > secondaries according to a variable called rapidity. In experiments, > > > > > calorimeters are then arranged around the collision point and > > > > > segmented in regular rapidity bins. Naturally, because the two > > > > > experiments are viewing the same collisions from two different > > > > > reference frames, the length binning for equal rapidity bins is > > > > > considerably different, precisely because of Lorentz contraction. > > > > > Thus, the distribution by rapidity, as shown by the particle deposits > > > > > in the calorimeter, is an indirect but definitive check on Lorentz > > > > > contraction. Experimentally, the match-up is exquisite. > > > > > > It's unfortunate that your web references are not accurate on this > > > > > score, and have led you to the impression that Lorentz contraction is > > > > > all hypothetical and without experimental support. I will just > > > > > attribute this to the lack of depth of experimental information you've > > > > > been able to lay your hands on. > > > > > > > > As I mentioned before, the first thing one must do in the case of an > > > > > > > observational science, is to not deny what is actually seen in > > > > > > > experiment, just because you do not immediately understand how that > > > > > > > outcome could arise. > > > > > > > No one is denying what is seen. The ladder and barn paradox has never > > > > > > been "seen". We have merely reasoned, using the tenets of SR, that > > > > > > this is what we *would* see, if we were able to perform an experiment. > > > > > > And equivalent experiments, those that demonstrate this effect, have > > > > > indeed been done. > > > > > > > But as I've said previously, even if this *is* what we would "see", > > > > > > seeing is not necessarily believing. > > > > > > And this is what I'm telling you is a bad policy in science. If > > > > > experiment comes in conflict with common sense -- that is, if what you > > > > > see is in conflict with what you understand -- then it is common sense > > > > > that should properly give way. I understand fully that you say you > > > > > just don't operate that way, and don't see why you should have to.. > > > > > > > Incidentally, I seem to remember Terrell ruled out any real > > > > > > observation of this contraction. > > > > > > > > As indicated above, the doors are closed and then opened by a single > > > > > > > trigger and equal-length, exchangeable cables. There is no catastrophe > > > > > > > observed. > > > > > > > You're asserting this. There is no experimental evidence of this being > > > > > > the case. > > > > > > You are wrong. > > |