Galilean transformation equations
in [Relativity]
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From: PD on 26 Jun 2010 15:11 On Jun 26, 1:26 pm, rbwinn <rbwi...(a)gmail.com> wrote: > On 26 June, 07:31, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jun 26, 8:26 am, rbwinn <rbwi...(a)gmail.com> wrote: > > > > On 25 June, 18:06, eric gisse <jowr.pi.nos...(a)gmail.com> wrote: > > > > > rbwinn wrote: > > > > > [...] > > > > > > I know a psychologist who was trying to drill through a board with an > > > > > electric drill, and he was having great difficulty. He said to > > > > > himself, This drill bit is obviously very dull, so he applied more > > > > > pressure, and after a long difficult time he was able to get the hole > > > > > drilled completely through the board, although it was more burned than > > > > > drilled. > > > > > Then he discovered that he had drilled completely through a > > > > > board with the drill running in reverse. > > > > > Compare and contrast with Robert B. Winn, the welder by trade, who has spent > > > > 15 years discussing concepts he does not understand. > > > > > Observe as he struggles mightily with the basic question of 'what is t'?'. > > > > > > College graduates are certainly interesting people. > > > > > As opposed to people like Robert B. Winn who are proud of not knowing > > > > things. > > > > I know there is no length contraction. > > > Well, Robert, you claim to KNOW something but without the benefit of > > direct observation in cases where the length contraction is advertised > > to be easily measurable. Thus you are claiming to KNOW something you > > really don't know anything about. This would be like claiming to KNOW > > all about somebody without ever having met them. It would be ... > > idiotic. > > > > That means that t' is time on > > > a clock in S. Nothing to struggle with there that I can see. > > Well, you are certainly welcome to your opinion, PD. Yes, I certainly am, Robert. I wouldn't be a bit surprised if it's a common perception about what you claim. You are certainly welcome to your own opinion, too, Robert. But an opinion is different than claiming to KNOW something, especially if it's a claim about knowing something you don't know anything about. PD
From: PD on 26 Jun 2010 15:14 On Jun 26, 1:26 pm, rbwinn <rbwi...(a)gmail.com> wrote: > On 26 June, 07:29, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jun 25, 7:00 pm, rbwinn <rbwi...(a)gmail.com> wrote: > > > > On 25 June, 08:50, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Jun 24, 10:59 pm, rbwinn <rbwi...(a)gmail.com> wrote: > > > > > > On 24 June, 07:24, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > They agree within the precision of the measurements you make. That's > > > > > > because theGalileantransformation are an excellent *approximation* > > > > > > to the real thing, especially at the low speeds that welders like to > > > > > > work with. As I told you before, Robert, feel free to use theGalilean > > > > > > transforms if they work for you and your needs. Physicists, on the > > > > > > other hand, sometimes work in domains where theGalileantransforms > > > > > > don't work well at all, because they don't always agree with > > > > > > measurments. It's in those cases that they're more careful, where > > > > > > you're happy to be simple and sloppy. > > > > > > > PD > > > > > > Well, I have noticed that with regard to people who subscribe to > > > > > disciplines. In any event, you may have noticed that I only apply the > > > > >Galileantransformation equations to two frames of reference at a > > > > > time. > > > > > And depending on the precision of your measurements of x, y, z, t, x', > > > > y', z', t', and how big v is, those transformations will provide you > > > > sufficient accuracy to work well enough. After all, 1.002 inches +/- > > > > 0.003 inches and 1.004 inches +/- 0.002 inches are EQUAL to the > > > > precision of those numbers. > > > > > But in other cases, you will find that those transformations do not > > > > work well at all, and there is no way the equality can be believed. > > > > > > When I say t'=t, I am not talking about all clocks in the > > > > > universe, just to the two references to time that are measuring these > > > > > equations: > > > > > > x'=x-vt > > > > > y'=y > > > > > z'=z > > > > > t'=t > > > > > > Consequently, if I say that t' is time on a clock in S, the equations > > > > > are satisfied, regardless of what a clock running at a different rate > > > > > may say. > > > > > Well, you can say that all you want, Bobby, but then you aren't using > > > > theGalileantransformations, because theGalileantransformations are > > > > more than algebraic equations. In theGalileantransformations, the > > > > variables actually have a specific meaning, otherwise they are no > > > > longer theGalileantransformations. (This is what marks the > > > > difference between physics and algebra. In algebra, you can say the > > > > variables stand for anything you want them to stand for. In physics, > > > > you cannot.) > > > > > > As a scientist, you may not like this, but if so, prove it > > > > > wrong. Just complaining about an equation does not prove anything. > > > > > I'm not complaining about anything, Bobby. I'm just making a simple > > > > statement that the variables in the transformation mean something > > > > specific in physics, and that those transformations turn out not to > > > > work so well in a variety of circumstances, and so I'm not inclined to > > > > use something that does not work well. I would not use a hammer to > > > > drive a deck screw, either, even if there were nothing wrong with the > > > > hammer. > > > > > PD > > > > I know a psychologist who was trying to drill through a board with an > > > electric drill, and he was having great difficulty. He said to > > > himself, This drill bit is obviously very dull, so he applied more > > > pressure, and after a long difficult time he was able to get the hole > > > drilled completely through the board, although it was more burned than > > > drilled. > > > Then he discovered that he had drilled completely through a > > > board with the drill running in reverse. > > > College graduates are certainly interesting people. > > > So are welders attempting to useGalileantransformations where they > > do not work at all well. > > > So you see, some welders seem to have the same foibles and goofball > > tactics that you've sometimes observed with college graduates. This > > should caution you about being prejudicial about classes of people, > > no? > > > PD > > The Galilean transformation equations seem to me to work just fine. > What problem were you having with them? I've already told you, Robert. They may work just fine with the measurements you wish to do, at the precision with which you measure them. Physicists often use them too as a handy approximation. But they also have to deal with many situations where they do not work at all well. On the other hand, you seem to be ok just as long as they appear to be legitimate algebraic equations and just as long as they fit your preconceived notions about the world. You don't seem to worry much at all about whether measurements play a role in their usage or not. This is where what you do with them becomes barely discernible from whittling a stick with a pocket knife. PD
From: YBM on 26 Jun 2010 15:29 PD a �crit : > On Jun 26, 1:24 pm, rbwinn <rbwi...(a)gmail.com> wrote: >> On 26 June, 07:25, PD <thedraperfam...(a)gmail.com> wrote: >> >> >> >> >> >>> On Jun 25, 6:42 pm, rbwinn <rbwi...(a)gmail.com> wrote: >>>> On 25 June, 08:42, PD <thedraperfam...(a)gmail.com> wrote: >>>>> On Jun 24, 10:48 pm, rbwinn <rbwi...(a)gmail.com> wrote: >>>>>> On 24 June, 07:19, PD <thedraperfam...(a)gmail.com> wrote: >>>>>>> On Jun 23, 7:39 pm, rbwinn <rbwi...(a)gmail.com> wrote: >>>>>>>> On 23 June, 07:01, PD <thedraperfam...(a)gmail.com> wrote: >>>>>>>>>> Well, I do not flog horses. I don't need to. Generally, I walk >>>>>>>>>> wherever I go. One thing is obvious to me, scientists are >>>>>>>>>> perpetrating a flim-flam. So I give them an example, easy to >>>>>>>>>> understand, marks every ten meters on S and marks every ten meters on >>>>>>>>>> S', and they pretend they do not understand how that could be. >>>>>>>>> Oh, it COULD be, Robert. Except it isn't so in reality. Measurement >>>>>>>>> shows this. >>>>>>>> Well, there is the difference between science and reality. Reality is >>>>>>>> more than a flim-flam. >>>>>>>> It actually exists. >>>>>>> Measurement reveals what exists, Robert, not your head. You rely too >>>>>>> much on your head and are too suspicious of measurements. This is how >>>>>>> you lose touch with reality. >>>>>>> PD >>>>>> I was not the one who lost touch with reality. I am not the one who >>>>>> believes in a length contraction. >>>>> It's not a matter of belief, Robert. It's a matter of *measurement*. >>>>> Now you may *choose* to say, "To hell with measurements if >>>>> measurements suggest I should believe in something I don't want to >>>>> believe." This is the approach that is taken by many creationists, who >>>>> choose what to believe first and then sift through the measurements to >>>>> select the ones that support what they want to believe. That's fine if >>>>> you want to act like a creationist, Robert. To a scientist, though, >>>>> that is intellectual dishonesty of the worst kind. >>>>> PD >>>> I just follow the math, PD. >>> I've already told you, Robert, that algebra can prove or disprove >>> nothing about the physical nature of the universe. One needs to attach >>> the math to *measurements* to test whether what you're doing with the >>> math has any connection to reality or not. >>> "Just following the math" is a pointless exercise in physics. >>> PD >> Not as pointless as scientists might believe. > > So says a welder who wants to play with mathematics. Go ahead and play > with high school algebra if that's your hobby, Robert. I'm sure it's > fulfilling. You're just missing the pieces that would make it relevant > to physics. BTW, Robert's skills in algebra are as bas as his skills in physics. His whole bunch of formulas with GT and n' fails at the basic algebraic level, as I've shown him numerous times.
From: PD on 26 Jun 2010 15:46 On Jun 26, 2:29 pm, YBM <ybm...(a)nooos.fr.invalid> wrote: > PD a crit : > > > > > > > On Jun 26, 1:24 pm, rbwinn <rbwi...(a)gmail.com> wrote: > >> On 26 June, 07:25, PD <thedraperfam...(a)gmail.com> wrote: > > >>> On Jun 25, 6:42 pm, rbwinn <rbwi...(a)gmail.com> wrote: > >>>> On 25 June, 08:42, PD <thedraperfam...(a)gmail.com> wrote: > >>>>> On Jun 24, 10:48 pm, rbwinn <rbwi...(a)gmail.com> wrote: > >>>>>> On 24 June, 07:19, PD <thedraperfam...(a)gmail.com> wrote: > >>>>>>> On Jun 23, 7:39 pm, rbwinn <rbwi...(a)gmail.com> wrote: > >>>>>>>> On 23 June, 07:01, PD <thedraperfam...(a)gmail.com> wrote: > >>>>>>>>>> Well, I do not flog horses. I don't need to. Generally, I walk > >>>>>>>>>> wherever I go. One thing is obvious to me, scientists are > >>>>>>>>>> perpetrating a flim-flam. So I give them an example, easy to > >>>>>>>>>> understand, marks every ten meters on S and marks every ten meters on > >>>>>>>>>> S', and they pretend they do not understand how that could be. > >>>>>>>>> Oh, it COULD be, Robert. Except it isn't so in reality. Measurement > >>>>>>>>> shows this. > >>>>>>>> Well, there is the difference between science and reality. Reality is > >>>>>>>> more than a flim-flam. > >>>>>>>> It actually exists. > >>>>>>> Measurement reveals what exists, Robert, not your head. You rely too > >>>>>>> much on your head and are too suspicious of measurements. This is how > >>>>>>> you lose touch with reality. > >>>>>>> PD > >>>>>> I was not the one who lost touch with reality. I am not the one who > >>>>>> believes in a length contraction. > >>>>> It's not a matter of belief, Robert. It's a matter of *measurement*.. > >>>>> Now you may *choose* to say, "To hell with measurements if > >>>>> measurements suggest I should believe in something I don't want to > >>>>> believe." This is the approach that is taken by many creationists, who > >>>>> choose what to believe first and then sift through the measurements to > >>>>> select the ones that support what they want to believe. That's fine if > >>>>> you want to act like a creationist, Robert. To a scientist, though, > >>>>> that is intellectual dishonesty of the worst kind. > >>>>> PD > >>>> I just follow the math, PD. > >>> I've already told you, Robert, that algebra can prove or disprove > >>> nothing about the physical nature of the universe. One needs to attach > >>> the math to *measurements* to test whether what you're doing with the > >>> math has any connection to reality or not. > >>> "Just following the math" is a pointless exercise in physics. > >>> PD > >> Not as pointless as scientists might believe. > > > So says a welder who wants to play with mathematics. Go ahead and play > > with high school algebra if that's your hobby, Robert. I'm sure it's > > fulfilling. You're just missing the pieces that would make it relevant > > to physics. > > BTW, Robert's skills in algebra are as bas as his skills in physics. > His whole bunch of formulas with GT and n' fails at the basic algebraic > level, as I've shown him numerous times. Yes, so I've seen. And I'm quite confident that Robert blames college- educated people for his poor algebra skills. He's already blamed college-educated people for his being a sucker for a self-publication scam. Robert's not to blame for any of his troubles, you see. PD
From: rbwinn on 26 Jun 2010 17:52
On Jun 26, 12:14 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Jun 26, 1:26 pm, rbwinn <rbwi...(a)gmail.com> wrote: > > > > > > > On 26 June, 07:29, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Jun 25, 7:00 pm, rbwinn <rbwi...(a)gmail.com> wrote: > > > > > On 25 June, 08:50, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Jun 24, 10:59 pm, rbwinn <rbwi...(a)gmail.com> wrote: > > > > > > > On 24 June, 07:24, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > They agree within the precision of the measurements you make. That's > > > > > > > because theGalileantransformation are an excellent *approximation* > > > > > > > to the real thing, especially at the low speeds that welders like to > > > > > > > work with. As I told you before, Robert, feel free to use theGalilean > > > > > > > transforms if they work for you and your needs. Physicists, on the > > > > > > > other hand, sometimes work in domains where theGalileantransforms > > > > > > > don't work well at all, because they don't always agree with > > > > > > > measurments. It's in those cases that they're more careful, where > > > > > > > you're happy to be simple and sloppy. > > > > > > > > PD > > > > > > > Well, I have noticed that with regard to people who subscribe to > > > > > > disciplines. In any event, you may have noticed that I only apply the > > > > > >Galileantransformation equations to two frames of reference at a > > > > > > time. > > > > > > And depending on the precision of your measurements of x, y, z, t, x', > > > > > y', z', t', and how big v is, those transformations will provide you > > > > > sufficient accuracy to work well enough. After all, 1.002 inches +/- > > > > > 0.003 inches and 1.004 inches +/- 0.002 inches are EQUAL to the > > > > > precision of those numbers. > > > > > > But in other cases, you will find that those transformations do not > > > > > work well at all, and there is no way the equality can be believed. > > > > > > > When I say t'=t, I am not talking about all clocks in the > > > > > > universe, just to the two references to time that are measuring these > > > > > > equations: > > > > > > > x'=x-vt > > > > > > y'=y > > > > > > z'=z > > > > > > t'=t > > > > > > > Consequently, if I say that t' is time on a clock in S, the equations > > > > > > are satisfied, regardless of what a clock running at a different rate > > > > > > may say. > > > > > > Well, you can say that all you want, Bobby, but then you aren't using > > > > > theGalileantransformations, because theGalileantransformations are > > > > > more than algebraic equations. In theGalileantransformations, the > > > > > variables actually have a specific meaning, otherwise they are no > > > > > longer theGalileantransformations. (This is what marks the > > > > > difference between physics and algebra. In algebra, you can say the > > > > > variables stand for anything you want them to stand for. In physics, > > > > > you cannot.) > > > > > > > As a scientist, you may not like this, but if so, prove it > > > > > > wrong. Just complaining about an equation does not prove anything. > > > > > > I'm not complaining about anything, Bobby. I'm just making a simple > > > > > statement that the variables in the transformation mean something > > > > > specific in physics, and that those transformations turn out not to > > > > > work so well in a variety of circumstances, and so I'm not inclined to > > > > > use something that does not work well. I would not use a hammer to > > > > > drive a deck screw, either, even if there were nothing wrong with the > > > > > hammer. > > > > > > PD > > > > > I know a psychologist who was trying to drill through a board with an > > > > electric drill, and he was having great difficulty. He said to > > > > himself, This drill bit is obviously very dull, so he applied more > > > > pressure, and after a long difficult time he was able to get the hole > > > > drilled completely through the board, although it was more burned than > > > > drilled. > > > > Then he discovered that he had drilled completely through a > > > > board with the drill running in reverse. > > > > College graduates are certainly interesting people. > > > > So are welders attempting to useGalileantransformations where they > > > do not work at all well. > > > > So you see, some welders seem to have the same foibles and goofball > > > tactics that you've sometimes observed with college graduates. This > > > should caution you about being prejudicial about classes of people, > > > no? > > > > PD > > > TheGalileantransformation equations seem to me to work just fine. > > What problem were you having with them? > > I've already told you, Robert. They may work just fine with the > measurements you wish to do, at the precision with which you measure > them. > Physicists often use them too as a handy approximation. But they also > have to deal with many situations where they do not work at all well. > > On the other hand, you seem to be ok just as long as they appear to be > legitimate algebraic equations and just as long as they fit your > preconceived notions about the world. You don't seem to worry much at > all about whether measurements play a role in their usage or not. This > is where what you do with them becomes barely discernible from > whittling a stick with a pocket knife. > > PD I don't worry at all. So you want to talk about measurements, just choose the ones you want to talk about. |