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From: Androcles on 27 Jul 2010 04:46 "Helmut Wabnig" <hwabnig@ .- --- -. dotat> wrote in message news:ma0t46ldnj8a4ms4k4afll2fncb5ajstvg(a)4ax.com... | On Tue, 27 Jul 2010 04:14:10 +0100, "Androcles" | <Headmaster(a)Hogwarts.physics_z> wrote: | | > | >"xxein" <xxxxein(a)gmail.com> wrote in message | >news:7668fbfa-d655-4b55-b298-be75f04a2a04(a)f8g2000vbl.googlegroups.com... | >On Jul 16, 9:48 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: | >> xxein wrote: | >> > Does anyone out there know how velocity addition | >> > works to describe how we measure it besides a math? What is the | >> > physical reason? | >> | >> Consider a pointlike object moving with constant velocity v along the x | >> axis, | >> and plot its x position vs time t. You'll get a straight line with a slope | >> of v. | >> Now do the same for 2v, and get a straight line with slope 2v. In such a | >> graph, | >> relative velocity is a rotation of the axes, and by considering the angle | >> related to the relative velocity, not its slope, it's clear that in | >> Galilean | >> relativity when composing relative velocities the angles merely add (when | >> plotted on a Euclidean piece of paper). | >> | >> In relativity there is also an angle associated with relative velocity, | >> called | >> rapidity. When composing relative velocities, their rapidities add. But | >> this is | >> hyperbolic geometry, and when plotted on a Euclidean piece of paper the | >> angles | >> corresponding to the rapidities do not simply add, they combine in such a | >> way | >> that the sum of angles never exceeds 45 degrees (= the invariant speed of | >> the | >> Lorentz transform = the speed of light). | >> | >> If you think this is far fetched, remember that v is the slope of the | >> relative | >> velocity, not an angle. Look up the formula for composing two Euclidean | >> rotations in terms of the slopes of lines and you'll find a formula quite | >> similar to the Lorentz addition of velocities, differing only in a sign. | >> | >> You'll also find that composing two large-enough slopes can | >> flip the sign of the line's slope. That's highly unphysical | >> when applied to relative velocities.... | >> | >> As for "why" hyperbolic geometry applies rather than Euclidean geometry, | >> that is | >> outside the realm of science. In the world we inhabit it just does. | >> | >> > I know what it is but I doubt that anyone else does. | >> | >> Such hubris! Such cowardice! | >> | >> Tom Roberts | > | >xxein: You don't understand the physic. All you understand is | >Einstein. I'm lightyears ahead of you. I can put Einstein's physical | >explanations of STR and GTR in the trash. His cumbersome math can | >somehow survive though. But NASA uses the simple form of Newton's and | >makes in-flight corrections. | > | ######################################################### | hans hanson said: | | Engineers don't need relativity. | | Androcles says: | | Engineers don't need theories, they do it all by trial-and-error. | (emphasis on the latter) | | | http://www.youtube.com/watch?v=j-zczJXSxnw | http://www.youtube.com/watch?v=_10T4UYpzV8 | http://www.youtube.com/watch?v=Qid2s89OfZU | | w. Wabnigga says: "I can write a nonsenses like xxein" | ######################################################### | | >What is the orbit velocity of any small mass around any large mass at | >3M (M = the mass in meters used as a radius)? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > It is always the same | >orbit velocity, right? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >You have a lot of math to go through to show | >this. How about: sqrt(c^2 - escape velocity^2) = orbit velocity? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >It | >gives the same velocity as Einstein, doesn't it? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >Light bends in | >gravity. It can only circularly orbit at 3M, right? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > Are you going to | >say that it's orbit velocity is c, or is light too special and doesn't | >have to follow the rules of the physic? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >This is where both Newton and Einstein made a wrong assumption. | >Newton was correct with the amount of curvature of light around mass. | >Einstein came up with twice the curvature to make the path length | >greater. Experiments verified this. Or did they? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >No! | >============================================ | > It's not an artefactual/superficially imposed yin-yang of sorts. | > | >They only verified the time that light took because of a bent | >path. It was affixed to speed c and so the curvature had to be | >doubled. | > | >Here's an interesting math playground for you that will perplex you. | >Take your spaceship to any M radius and hover there. You are not | >moving wrt the central mass but you have a gravitational time | >dilation, right? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >Incidentally, it is the same time dilation you would | >compute if you were traveling at the value of your escape velocity. | >Compute it. Everything you see and measure is with a slow clock. | > | >You are on the shell wrt a sphere. Here comes some light that will | >graze the tangent point of where you are. You are in gravity and | >expect that the light was bent. Do you measure it as c? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > | > Of course. | >But how with a slow clock? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > | >There's only one physical answer. Light is not traveling at c. Just | >as it is not orbiting 3M at c. | > | >This tangent light is subject to the same vector velocities as | >anything else. Sqrt(c^2 - escape velocity^2) = it's path velocity at | >that point. It is only the square of the sums that equals c. | > | >So how did you measure it at c? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >You computed your timerate on that | >shell, right? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >What is the vector velocity of light as it grazes you? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | >The same numeric value. | > | >This means that if light came to you at a speed (x) (not it's | >velocity), you would see and meaure it as c. x/x=1=c to you. But the | >important physic to be derived from this is that c is a constant in | >the measure of it only. | > | >Be a good old boy and I might just explain how velocity addition works | >in the physic - not just a math. So simple, really. Who knows? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > I | >might even tell you what gravity is. All this will keep you decades | >to explore. | > | >Cowardice? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > Examine yourself for being a follower and not an explorer | >of the physic. Hubris? | >============================================ | > It's an artefactual/superficially imposed yin-yang of sorts. | > | > I earned mine. I didn't take it by copy and | >paste. But you are very good at that. |
From: harald on 27 Jul 2010 06:30 On Jul 27, 4:57 am, xxein <xxxx...(a)gmail.com> wrote: > On Jul 16, 9:48 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: [..] > This is where both Newton and Einstein made a wrong assumption. > Newton was correct with the amount of curvature of light around mass. > Einstein came up with twice the curvature to make the path length > greater. Experiments verified this. Or did they? > > No! They only verified the time that light took because of a bent > path. It was affixed to speed c and so the curvature had to be > doubled. No, instead Eddington and others after him measured the *angle* of displacement of the image of stars. Harald
From: Helmut Wabnig hwabnig on 28 Jul 2010 04:21 On Wed, 28 Jul 2010 09:59:38 +0200, Helmut Wabnig <hwabnig@ .- --- -. dotat> wrote: >and me did work in such a place where they said: > > >NEVER STOP THINKING ! Germans have problems pronouncing the THORN http://en.wikipedia.org/wiki/Thorn_(letter) and they pronounce it like letter s which mutated the slogan to NEVER STOP SINKING ! hehe, and look at the stock market.... hahaha, not-so-funny for many, but I did not buy shares. w.
From: Torn Rumero DeBrak on 28 Jul 2010 08:44 Helmut Wabnig wrote: > On Wed, 28 Jul 2010 09:59:38 +0200, Helmut Wabnig <hwabnig@ .- --- -. > dotat> wrote: > >> and me did work in such a place where they said: >> >> >> NEVER STOP THINKING ! > > > > Germans have problems pronouncing the THORN > http://en.wikipedia.org/wiki/Thorn_(letter) > and they pronounce it like letter s > which mutated the slogan to > > NEVER STOP SINKING ! > And what about the SINQUEEN?
From: Androcles on 28 Jul 2010 09:07
"Helmut Wabnig" <hwabnig@ .- --- -. dotat> wrote in message news:dppv4615g5tkat6i5cla9tkias8rmpl329(a)4ax.com... | On Wed, 28 Jul 2010 09:59:38 +0200, Helmut Wabnig <hwabnig@ .- --- -. | dotat> wrote: | | >and me did work in such a place where they said: | > | > | >NEVER STOP THINKING ! To be able to do that you'd have to have started. | | Germans have problems pronouncing the THORN | http://en.wikipedia.org/wiki/Thorn_(letter) | and they pronounce it like letter s | which mutated the slogan to | | NEVER STOP SINKING ! | | hehe, and look at the stock market.... | hahaha, | not-so-funny for many, but I did not buy shares. | | w. That's ok, the English-speaking people world-wide have problems with nearly all aspects of their own Celtic language. http://en.wikipedia.org/wiki/Mynydd_Mawr That "dd" in Mynydd is pronounced "d(thorn)" and the "w" in "Mawr" is literally "uu" or "double-u". The technology of printing caused the mutation (evolution) when the shape of letters (which had grown out of the Greek and Latin form) became standardised by pouring lead into moulds to make multiple copies. The spoken form of the word continued on from parent to child, the written form changed simply because the thorn letter was not part of the standard Latin text that 13th century scribes used. The word "llyn" (meaning "lake" or in German, "See") is often mispronounced "klin" because the sound "ll" is never learned in childhood by the English but soon learned by the Welsh. To say it correctly, curl the tip of the tongue backward touching the roof of the mouth and keeping the mouth slightly open, breathe out rapidly allowing the tongue to relax, flopping forward. |