An apology to Androcles
in [Relativity]
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From: Helmut Wabnig hwabnig on 4 Aug 2010 01:39 On Tue, 3 Aug 2010 19:08:20 +0100, "Androcles" <Headmaster(a)Hogwarts.physics_z> wrote: > >"Helmut Wabnig" <hwabnig@ .- --- -. dotat> wrote in message >news:muhg56tlfmnr9j968ip270e3rdi79j865g(a)4ax.com... >| On Tue, 3 Aug 2010 12:40:44 +0100, "Androcles" >| <Headmaster(a)Hogwarts.physics_z> wrote: >| >| > >| >"Helmut Wabnig" <hwabnig@ .- --- -. dotat> wrote in message >| >news:8kuf5694d6ib9lcdreafmu0omlint9bmih(a)4ax.com... >| >| On Mon, 2 Aug 2010 12:54:17 -0700 (PDT), PD >| >| <thedraperfamily(a)gmail.com> wrote: >| >| >| >| >On Jul 31, 8:54 am, Uncle Ben <b...(a)greenba.com> wrote: >| >| >> On Jul 30, 11:31 pm, eric gisse <jowr.pi.nos...(a)gmail.com> wrote: >| >| >> >| >| >> > Uncle Ben wrote: >| >| >> >| >| >> > [...] >| >| >> >| >| >> > The androcles lost the ability to reason with people long ago. >| >| >> >| >| >> You may be right, Eric. It takes integrity to admit error. I thought >| >| >> that if the truth were spelled out with such clarity that even his >| >| >> lion could understand it, Androcles might man up enough to display >| >| >> some integrity and recover some respect. Otherwise, it is killfile >| >| >> time. >| >| > >| >| >That seems best. I've seen Androcles stick to a claim that 2 = 1/2 in >| >| >the past. >| >| >| >| Einstein divided by ZERO, said the lionkeeper....in the past. >| >| >| > >| >Not difficult to understand, Wabnigga. >| >c = limit as h tends to zero of [f(x+h) - f(x)] / h >| > >| >"Hence if x' be taken infinitesimally small" -- Einstein. >| >"the velocity of light in our theory plays the part, physically, of an >| >infinitely great velocity". -- Einstein. >| >t = x/c = (not much)/infinity = 0. >| >tau = integral [dtau/dt].dt for t = 0 to 0. >| > >| >The boneheaded trolls never had the ability to reason and never learned >| >mathematics. >| >Einstein divided by zero, ewe cretin. >| > >| >| Androcles, the educationally subnormal. >| >| Calculating "limits" has nothing to do with DIVISION BY ZERO! >| http://en.wikipedia.org/wiki/Limit_of_a_function >| >| >| Andro, this has been explained to you a zillion times: >| http://mathworld.wolfram.com/LHospitalsRule.html >| >| >| No division by Zero, >| Andro! >| >| NO DIVISION BY ZERO, >| Androcles! >| >| N O D I V I S I ON B Y Z E R O >| Mr. Androcles! >| >| M I S T E R A N D R O C L E S !!!! >| >| w. > >"Hence if x' be taken infinitesimally small" -- Einstein. > That's not L'Hospital's Rule!!!!!!!!!! >What's that for, Missus Fuckwad!!!!!!!!!!!!!!!!!!! ? c = limit as h tends to zero of [f(x+h) - f(x)] / h No division by zero "Hence if x' be taken infinitesimally small" -- Einstein. t = x/c = (not much)/infinity = 0. No division by zero. Where does Herr Androcles see a division by zero? w.
From: harald on 4 Aug 2010 05:48 On Jul 30, 9:10 pm, Uncle Ben <b...(a)greenba.com> wrote: > An apology to Androcles > > I had thought that the Einstein Expansion, proclaimed by Androcles in > sci.physics.relativity, was an error of confusing > frames of reference. But I was wrong. I had not followed that particular discussion, but it's about a known topic. See below, you may be surprised! > In his 1905 relativity paper, Einstein showed that x' = xi/gamma, > where x' is the length of a moving rod with respect to a stationary > frame of reference K and xi is the length of the moving rod with > respect to a frame k comoving with it. Note: In that paper, x' is a *value* that corresponds to a *point* co- moving with the moving system, as measured with the stationary coordinate system. However, that value x' also corresponds to a moving *distance* with respect to the stationary system, that has the endpoints O' and xi on the moving system. Similarly the value of xi corresponds to a length as measured with the moving system. > My difference with Androcles > was that I claimed that xi is the proper length L of the rod and the > shorter x' is a contracted length L/gamma. x' is a value that corresponds to a moving distance along X as measured in the stationary system K. Einstein does not designate a rod with length "L" to that distance, but he does do so for a similar measurement along Y. > I thought that Androcles had these two backward. But no, he has > persuaded me otherwise; He agrees that x' is shorter than xi, but he > insists that x' is L and xi is an expanded length Lgamma. Indeed, "L" is used by Einstein for distances as measured in the *stationary* system. That is also common practice in textbook derivations such as by Alonso&Finn which has L=L'/gamma, so that the co-moving length L'= L*gamma. L' is equal to the "proper" length L0 of a co-moving rod. > The proper > length of the rod in k increases because of the existence of another > frame of reference K moving with respect to it. I beg you pardon? The proper length of a rod cannot be affected by another reference frame, but it is clear from what follows that you are joking. > (This other frame K is > called the "stationary" frame in Einstein's paper, but it can be > considered moving the other way with respect to the > rest frame k of the rod.) > > This startling fresh idea would never have occurred to > me without Androcles's guidance. > > It seems strange that a nearby frame of reference K, by its relative > motion, can expand a rod with respect to the rod's own proper frame k, > while the rod maintains a constant length with respect to K itself. With a contracted ruler you measure a length L as gamma*L; that can be confusing but there is nothing strange about it! > Imagine me in a Concorde (k) flying over you on the ground (K) sucking > on my cigar that had length L when I bought it. It seems strange that > to you the cigar has length L, but because I am flying within your > frame of reference, my cigar is Lgamma long. In fact, because of your > frame of reference, the Concord is stretched by gamma for me but not > for you. I have no idea why my cigar is now longer, because I have no > idea that you are down there. > > It seems odd, doesn't it. Perhaps Androcles will explain it to us. You confused coordinate length with proper length; on this point Androcles was right (surprise!). Regards, Harald
From: harald on 4 Aug 2010 06:27 [Correction, as I had overlooked a "phi":] On Jul 30, 9:10 pm, Uncle Ben <b...(a)greenba.com> wrote: > An apology to Androcles > I had thought that the Einstein Expansion, proclaimed by Androcles in > sci.physics.relativity, was an error of confusing > frames of reference. But I was wrong. I had not followed that particular discussion, but it's about a known topic. See below, you may be surprised! > In his 1905 relativity paper, Einstein showed that x' = xi/gamma, > where x' is the length of a moving rod with respect to a stationary > frame of reference K and xi is the length of the moving rod with > respect to a frame k comoving with it. Note: In that paper, x' is a *value* that corresponds to a *point* co- moving with the moving system, as measured with the stationary coordinate system. However, that value x' also corresponds to a moving *distance* with respect to the stationary system, that has the endpoints O' and xi on the moving system. Similarly the value of xi corresponds to a length as measured with the moving system. > My difference with Androcles > was that I claimed that xi is the proper length L of the rod and the > shorter x' is a contracted length L/gamma. x' is a value that corresponds to a moving distance along X as measured in the stationary system K. Einstein does not designate a rod with length L to such a distance; instead he does designate a rod with length L/phi for a similar measurement along Y. > I thought that Androcles had these two backward. But no, he has > persuaded me otherwise; He agrees that x' is shorter than xi, but he > insists that x' is L and xi is an expanded length Lgamma. No, L is used by Einstein for the "proper" length of a stationary rod as measured in a co-moving system. That differs from common, modern practice in textbook derivations in which the proper, co-moving length is indicated with L0, and L is used for the moving length as measured in the stationary system. > The proper > length of the rod in k increases because of the existence of another > frame of reference K moving with respect to it. I beg you pardon? The proper length of a rod cannot be affected by another reference frame, but it is clear from what follows that you are joking. > (This other frame K is > called the "stationary" frame in Einstein's paper, but it can be > considered moving the other way with respect to the > rest frame k of the rod.) > This startling fresh idea would never have occurred to > me without Androcles's guidance. > It seems strange that a nearby frame of reference K, by its relative > motion, can expand a rod with respect to the rod's own proper frame k, > while the rod maintains a constant length with respect to K itself. With a contracted ruler you measure a length L as gamma*L; that can be confusing but there is nothing strange about it! Textbooks such as by Alonso&Finn put L=L'/gamma, so that the co-moving length L'= L*gamma. Einstein did not use that notation, but there is nothing wrong with it (nor is it a "fresh" idea). > Imagine me in a Concorde (k) flying over you on the ground (K) sucking > on my cigar that had length L when I bought it. It seems strange that > to you the cigar has length L, but because I am flying within your > frame of reference, my cigar is Lgamma long. In fact, because of your > frame of reference, the Concord is stretched by gamma for me but not > for you. I have no idea why my cigar is now longer, because I have no > idea that you are down there. > It seems odd, doesn't it. Perhaps Androcles will explain it to us. Androcles doesn't need to explain what textbooks already explained (surprise!). Regards, Harald
From: Uncle Ben on 4 Aug 2010 09:14 On Aug 4, 6:27 am, harald <h...(a)swissonline.ch> wrote: > [Correction, as I had overlooked a "phi":] > > On Jul 30, 9:10 pm, Uncle Ben <b...(a)greenba.com> wrote: > > > An apology to Androcles > > I had thought that the Einstein Expansion, proclaimed by Androcles in > > sci.physics.relativity, was an error of confusing > > frames of reference. But I was wrong. > > I had not followed that particular discussion, but it's about a known > topic. See below, you may be surprised! > > > In his 1905 relativity paper, Einstein showed that x' = xi/gamma, > > where x' is the length of a moving rod with respect to a stationary > > frame of reference K and xi is the length of the moving rod with > > respect to a frame k comoving with it. > > Note: In that paper, x' is a *value* that corresponds to a *point* co- > moving with the moving system, as measured with the stationary > coordinate system. However, that value x' also corresponds to a moving > *distance* with respect to the stationary system, that has the > endpoints O' and xi on the moving system. Similarly the value of xi > corresponds to a length as measured with the moving system. > > > My difference with Androcles > > was that I claimed that xi is the proper length L of the rod and the > > shorter x' is a contracted length L/gamma. > > x' is a value that corresponds to a moving distance along X as > measured in the stationary system K. Einstein does not designate a rod > with length L to such a distance; instead he does designate a rod with > length L/phi for a similar measurement along Y. > > > I thought that Androcles had these two backward. But no, he has > > persuaded me otherwise; He agrees that x' is shorter than xi, but he > > insists that x' is L and xi is an expanded length Lgamma. > > No, L is used by Einstein for the "proper" length of a stationary rod > as measured in a co-moving system. That differs from common, modern > practice in textbook derivations in which the proper, co-moving length > is indicated with L0, and L is used for the moving length as measured > in the stationary system. > > > The proper > > length of the rod in k increases because of the existence of another > > frame of reference K moving with respect to it. > > I beg you pardon? The proper length of a rod cannot be affected by > another reference frame, but it is clear from what follows that you > are joking. > > > (This other frame K is > > called the "stationary" frame in Einstein's paper, but it can be > > considered moving the other way with respect to the > > rest frame k of the rod.) > > This startling fresh idea would never have occurred to > > me without Androcles's guidance. > > It seems strange that a nearby frame of reference K, by its relative > > motion, can expand a rod with respect to the rod's own proper frame k, > > while the rod maintains a constant length with respect to K itself. > > With a contracted ruler you measure a length L as gamma*L; that can be > confusing but there is nothing strange about it! > > Textbooks such as by Alonso&Finn put L=L'/gamma, so that the co-moving > length L'= L*gamma. Einstein did not use that notation, but there is > nothing wrong with it (nor is it a "fresh" idea). > > > Imagine me in a Concorde (k) flying over you on the ground (K) sucking > > on my cigar that had length L when I bought it. It seems strange that > > to you the cigar has length L, but because I am flying within your > > frame of reference, my cigar is Lgamma long. In fact, because of your > > frame of reference, the Concord is stretched by gamma for me but not > > for you. I have no idea why my cigar is now longer, because I have no > > idea that you are down there. > > It seems odd, doesn't it. Perhaps Androcles will explain it to us. > > Androcles doesn't need to explain what textbooks already explained > (surprise!). > > Regards, > Harald Harald, turn on your satire detector. Cheers! Ben
From: Androcles on 4 Aug 2010 09:48
"Uncle Ben" <ben(a)greenba.com> wrote in message news:0967ff5e-3f8a-4088-86cc-2e6e2db13454(a)d17g2000yqb.googlegroups.com... On Aug 4, 6:27 am, harald <h...(a)swissonline.ch> wrote: > [Correction, as I had overlooked a "phi":] > > On Jul 30, 9:10 pm, Uncle Ben <b...(a)greenba.com> wrote: > > > An apology to Androcles > > I had thought that the Einstein Expansion, proclaimed by Androcles in > > sci.physics.relativity, was an error of confusing > > frames of reference. But I was wrong. > > I had not followed that particular discussion, but it's about a known > topic. See below, you may be surprised! > > > In his 1905 relativity paper, Einstein showed that x' = xi/gamma, > > where x' is the length of a moving rod with respect to a stationary > > frame of reference K and xi is the length of the moving rod with > > respect to a frame k comoving with it. > > Note: In that paper, x' is a *value* that corresponds to a *point* co- > moving with the moving system, as measured with the stationary > coordinate system. However, that value x' also corresponds to a moving > *distance* with respect to the stationary system, that has the > endpoints O' and xi on the moving system. Similarly the value of xi > corresponds to a length as measured with the moving system. > > > My difference with Androcles > > was that I claimed that xi is the proper length L of the rod and the > > shorter x' is a contracted length L/gamma. > > x' is a value that corresponds to a moving distance along X as > measured in the stationary system K. Einstein does not designate a rod > with length L to such a distance; instead he does designate a rod with > length L/phi for a similar measurement along Y. > > > I thought that Androcles had these two backward. But no, he has > > persuaded me otherwise; He agrees that x' is shorter than xi, but he > > insists that x' is L and xi is an expanded length Lgamma. > > No, L is used by Einstein for the "proper" length of a stationary rod > as measured in a co-moving system. That differs from common, modern > practice in textbook derivations in which the proper, co-moving length > is indicated with L0, and L is used for the moving length as measured > in the stationary system. > > > The proper > > length of the rod in k increases because of the existence of another > > frame of reference K moving with respect to it. > > I beg you pardon? The proper length of a rod cannot be affected by > another reference frame, but it is clear from what follows that you > are joking. > > > (This other frame K is > > called the "stationary" frame in Einstein's paper, but it can be > > considered moving the other way with respect to the > > rest frame k of the rod.) > > This startling fresh idea would never have occurred to > > me without Androcles's guidance. > > It seems strange that a nearby frame of reference K, by its relative > > motion, can expand a rod with respect to the rod's own proper frame k, > > while the rod maintains a constant length with respect to K itself. > > With a contracted ruler you measure a length L as gamma*L; that can be > confusing but there is nothing strange about it! > > Textbooks such as by Alonso&Finn put L=L'/gamma, so that the co-moving > length L'= L*gamma. Einstein did not use that notation, but there is > nothing wrong with it (nor is it a "fresh" idea). > > > Imagine me in a Concorde (k) flying over you on the ground (K) sucking > > on my cigar that had length L when I bought it. It seems strange that > > to you the cigar has length L, but because I am flying within your > > frame of reference, my cigar is Lgamma long. In fact, because of your > > frame of reference, the Concord is stretched by gamma for me but not > > for you. I have no idea why my cigar is now longer, because I have no > > idea that you are down there. > > It seems odd, doesn't it. Perhaps Androcles will explain it to us. > > Androcles doesn't need to explain what textbooks already explained > (surprise!). > > Regards, > Harald Harald, turn on your satire detector. Cheers! Ben ----------------- "We imagine further that at the two ends A and B of the rod, clocks are placed which synchronize with the clocks of the stationary system"... not to be confused with the other two ends of the rod of length L, namely 0 and x, or the ends of the moving rod of length L', namely 0' and x', or the other moving rod of length lambda, namely 0 and xi. Your god seems to have plagiarised more than one paper if the way he confuses his variables is anything to go by. Lambda = L' * gamma. How amusing. I'm so glad everybody knows that is the "Lorentz contraction". EVERYBODY! So you concede defeat and have decided to shut up, don't have the integrity to admit it, yet have the cunning intelligence of the herd animal to seek the centre of the flock, knowing the wolf will take its prey from the periphery. |