Re: Superluminal Quasar Jets : The Beaming "Explanation" Appears Inadequate

From: George Dishman (george_at_briar.demon.co.uk)
Date: 02/27/05 

Date: Sun, 27 Feb 2005 10:56:06 -0000

<jgreen@seol.net.au> wrote in message
news:1109461004.939277.271580@f14g2000cwb.googlegroups.com...
>
> N:dlzc D:aol T:com (dlzc) wrote:
>>
>> Maxwell provides the conundrum I describe, since light travels at c for
>> all
>> observers, yet light leaves "forward" from an object travelling at c. He
>> seems to be running towards Fizeau next...
>
> Then wasn't Maxwell saying c'=c+v

David said "light travels at c for all observers"
hence c'=c.

http://www.fnal.gov/pub/inquiring/more/light/light_page9.html

> , and thus in direct conflict with AE?

See section 6 of Einstein's original paper:

http://www.fnal.gov/pub/inquiring/more/light/light_page9.html

> How is the increasing length per time (velocity) of these jets measured?

Length isn't too meaningful as the jets are a
continuous flow so there is no clear end to the
jet. Measuring the speed depends on non-uniformity
in the flow by following the progress of 'knots'
of matter. For example:

http://www.stsci.edu/ftp/science/m87/m87.html

and in particular this set of frames:

http://www.stsci.edu/ftp/science/m87/bw3.gif

Or look at the attached radio map here:

http://www.phy.duke.edu/~kolena/superluminalmotion.html

You might also practice your maths by trying
to answer the questions on that page ;-)

> SR believers might claim that the only legitimate measurement would be
> that of a traveller on the jet!

SR provides a set of rules for converting
measurements in one frame into another frame.
Both measurements are "legitimate" in their
respective frames.

> Otherwise, SR is decapitated right
> here, with the obvious and trivial observation that velocity has NOT
> shrunken the moving body!

It has. Someone riding on the jet would measure
a greater distance between the same knots than
an observer at rest wrt the source and viewing
the jet perpendicular to its motion.

George

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