Prev: Joan-Claude van Dirk Helps to Trivialize Special Relativity
Next: GOD=G_uv Measure your IQ in 30 seconds
From: bz on 28 Apr 2005 20:44 H@..(Henri Wilson) wrote in news:ebq27114h0j7ooce3h3vo1d6se1o4dspmn(a)4ax.com: > On Thu, 28 Apr 2005 21:11:51 +0000 (UTC), bz > <bz+sp(a)ch100-5.chem.lsu.edu> wrote: > >>H@..(Henri Wilson) wrote in >>news:b8h2719k4fhf6m6shbrsd7hqsbag8p3gh4(a)4ax.com: >> > >>>> >>>>Which is exactly what I am trying to demonatrate to the BaT people. >>>> >>>>They think that c'=c+v >>>>They think that the speed of light is dependent on the velocity of the >>>>source. >>> >>> No they don't. >>> >>> They say: >>> 1) 'speed of light' is a meaningless expression on its own. >> >>we disagree. > > The 'speed' of anything is a meaningless expression anywhere, anytime. Tell that to the policeman when he writes you a ticket. Speed is the magnitude of velocity, it is not meaningless. One may specify direction to give more information, but speed is a useful term to use when the direction does not matter. Speed of light is a commonly used and accepted term in physics. > >> >>> All speeds >>> must be defined as relative. >>we agree with the exception of things like light and sound that have >>constant velocities (assuming vacuum for light, uniform media for >>sound). > > For sound, speed is defined as relative to he medim in which it is > conveyed. Didn't you just say the "'speed' of anything is a meaningless expression anywhere, anytime"? Ah well "consistancy is the hobgobblin of small minds", as someone once said. But the shift is observable and is due to relative motion of source and observer. > For light in vacuum, there is no reference medium. So what? the shift is observable and is due to relative motion of source and observer. > The only > reference is its source. That is demonstrably false. Doppler shift of light, radar, and sound all depend on the relative velocity of the source and the observer. > The claim that light travels at 'c' wrt all observers is unsubstantiated > and nonsensical. The claim has never been falsified and makes sense to me. > >> >>> 2) Tthe speed of light happens to be 'c' wrt its source, >> >>we agree. >> >>> 'c' being a universal constant. >>> 3) Light from a moving source will move at c+v relative to the >>> observer. >> >>We disagree. >>Light moves at c wrt observer, wrt source, wrt all possible observers. > > The claim that light travels at 'c' wrt all observers is unsubstantiated > and nonsensical. The claim that light travels at 'c' wrt all observers has never been falsified. The claim that c'=c+v is unsubstatiated and seems nonsensical to me. > > >>> >>>>They actually think that the wavelength is constant and the speed >>>>varies. >>> >>> The frequency of an EM signal refers to the rate at which 'wavecrests' >>> pass a point. >> >>We agree. >> >>> Under the BaT, that rate is obviously dependent on relative light >>> speed. >> >>True, also under SR, GTR, and Newtonian physics. > > Not so under SR. > If so, it would not accommodate doppler shifts at all. It does accommodate doppler shift. The rate of passage of the wavecrests (frequency) is changed by a non zero relative velocity of source and observer. > >> >>> How could the distance between any two point be physically affected by >>> observer movement? There are lots of differently moving observers :) >> >>So? Each different observer can observe a different frequency, if their >>motion relative to the source is different. > > That has nothing whatsoever to do with the physical distance between the > points. We are talking here about 'point on the wave train', right? 'Wavecrests', right? A moving observer will see those points passing at a rate that is dependent upon the observers motion relative to the wave source. > Accept: OBSERVER MOVEMENTS DON'T AFFECT ANYTHING. I do NOT accept that. In fact, if you get a doppler lidar or radar and go riding around in your car with it, you will soon find that the relative velocity is what is measured. The observers movements certainly have an effect. >>It works that way with the doppler shift due to a moving sound source. >>Why wouldn't it work that way with light? > > Light doesn't travel through a medium. > >>> That is what you are other SRians claim...and in all seriousness!! >>> HaHa!!!! >> >>Do you agree that BaT does NOT apply to sound? > > How could it. Exactly my point. However one could argue that the moving source, when moving in the direction of wave propagation, will [and it really will] impart an additional kinetic motion to the air molecules and make them move faster. However this does not make the SOUND travel faster. > Sound is a moving disturbance in a fixed medium. We will agree that we are talking about observations taken in still air. > >>Do you agree that the speed of sound is independent of the speed of the >>source? > > Of course the speed of sound in the medium is independent of the source. Do you agree that doppler shift, of sound, can be observed by a moving observer, given a stationary source? Do you agree that doppler shift, of sound, can be observed by a stationary observer, given a moving source? Do you agree that doppler shift, of sound, is due to the relative motion between source and observer? Do you agree that multiple observers in different locations, of a moving source will each observe a different frequency? > >> >>If you don't agree, then we can easily do experiments that will show you >>are wrong. > > Where is the connection between sound and light. They both travel at constant velocities [usual disclaimers]. > > You obviously have a lot to learn. All human beings do. Life would not be much fine if that were not true. The set-of-things-I-do-not-know is an infinite set. -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+sp(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
From: G on 29 Apr 2005 00:08 bz To resolve this I have been thinking and put up a simple web page Starting from basics: A thought experiment or can we call it a computer software simulation based experiment? http://www.geocities.com/invent6620032003/anim.html "They think that the speed of light is dependent on the velocity of the source" Need to define terms carefully: the speed of light as measured by an observer who is moving relative to the source at velocity v or the speed of light as measured by an observer who is not moving relative to the source? I suspect these are different but I have to prove it. Not assuming SRT or BaT or anything except Newton and Galileo maybe and common sense G
From: G on 29 Apr 2005 00:22 They say: 1) 'speed of light' is a meaningless expression on its own. All speeds must be defined as relative. 2) Tthe speed of light happens to be 'c' wrt its source, 'c' being a universal constant. 3) Light from a moving source will move at c+v relative to the observer. Aha. We are getting to the core of the problem now 1 - agree, given that no-one agrees on absolute motion 2 - I have a problem here: subsititute the speed of light with the statement in (1) an d you get (2a) Tthe ** RELATIVE ** speed of light happens to be 'c' wrt its source, 'c' being a universal constant. Relative to whom? The observer? See my moving asteroid in empty space: If you are on the asteroid what speed does light travel from the laser? I admit I am beginning to get confused: maybe AE was as well? G
From: G on 29 Apr 2005 00:31 Henri Discussion is VERY interesting, relativistic effects of sound are something I have though much about. No time to reply maybe later See my animation for a bit and ponder http://www.geocities.com/invenÂt6620032003/anim.html G
From: bz on 29 Apr 2005 03:36
"G" <gehan(a)dialog.lk> wrote in news:1114747716.254187.268180 @z14g2000cwz.googlegroups.com: > bz > > To resolve this I have been thinking and put up a > simple web page Starting from basics: A thought experiment > or can we call it a computer software simulation based experiment? > > http://www.geocities.com/invent6620032003/anim.html > cute animation. On first readthru I noticed one typo. 'as ell as' should be 'as well as'. > "They think that the speed of light is dependent on the > velocity of the source" > > Need to define terms carefully: the speed of light as > measured by an observer who is moving relative to the > source at velocity v or the speed of light as measured by > an observer who is not moving relative to the source? > I suspect these are different but I have to prove it. > Not assuming SRT or BaT or anything except Newton and Galileo > maybe and common sense > > > > G > > -- bz please pardon my infinite ignorance, the set-of-things-I-do-not-know is an infinite set. bz+se(a)ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap |