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Wavelength, Frequency and Variable Speed of Light



 
 
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  #1  
Old April 6th 16, 08:51 AM posted to sci.astro
Pentcho Valev
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Default Wavelength, Frequency and Variable Speed of Light

Question in StackExchange:

http://physics.stackexchange.com/que...cy-wave-travel
"It is true when a wave is traveling in a constant velocity, there is an inverse relationship between a wavelength and frequency. For example, if a wavelength is increasing, frequency should decrease because it is an inverse relationship. However, what if the wave is not traveling constant? Will the formula and the concepts change?"

My answer (still not deleted by Einsteinians):

The wavelength cannot be changed by the motion of the observer, but the frequency and the speed of the waves (relative to the observer) do change:

http://physics.bu.edu/~redner/211-sp...9_doppler.html
"Let's say you, the observer, now move toward the source with velocity vO. You encounter more waves per unit time than you did before. Relative to you, the waves travel at a higher speed: v'=v+vO. The frequency of the waves you detect is higher, and is given by: f'=v'/λ=(v+vO)/λ."

Actually any interpretation of the Doppler effect (moving observer) proves, explicitly or implicitly, that the speed of light relative to the observer varies with the speed of the observer, in violation of Einstein's relativity:

http://www.hep.man.ac.uk/u/roger/PHY.../lecture18.pdf
"The Doppler effect - changes in frequencies when sources or observers are in motion - is familiar to anyone who has stood at the roadside and watched (and listened) to the cars go by. It applies to all types of wave, not just sound. (...) Moving Observer. Now suppose the source is fixed but the observer is moving towards the source, with speed v. In time t, ct/λ waves pass a fixed point. A moving point adds another vt/λ. So f'=(c+v)/λ. (...) Relativistic Doppler Effect (...) If the source is regarded as fixed and the observer is moving, then the observer's clock runs slow. They will measure time intervals as being shorter than they are in the rest frame of the source, and so they will measure frequencies as being higher, again by a γ factor: f'=(1+v/c)γf..."

That is, according to the above interpretation,

f' = (c+v)/λ

when v is low (relativistic corrections are negligible), and

f' = (1+v/c)γf = γ(c+v)/λ

when v is high. Accordingly, the speed of the light relative to the moving observer is

c' = c+v

when v is low, and

c' = γ(c+v)

when v is high. Einstein's relativity is violated in either case.

Pentcho Valev
  #2  
Old April 8th 16, 11:59 PM posted to sci.astro
Pentcho Valev
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Posts: 8,078
Default Wavelength, Frequency and Variable Speed of Light

http://phys.org/news/2016-03-optical-slower.html
"Researchers at the University of Ottawa observed that twisted light in a vacuum travels slower than the universal physical constant established as the speed of light by Einstein's theory of relativity. (...) In The Optical Society's journal for high impact research, Optica, the researchers report that twisted light pulses in a vacuum travel up to 0.1 percent slower than the speed of light, which is 299,792,458 meters per second. (...) If it's possible to slow the speed of light by altering its structure, it may also be possible to speed up light. The researchers are now planning to use FROG to measure other types of structured light that their calculations have predicted may travel around 1 femtosecond faster than the speed of light in a vacuum."

http://phys.org/news/2016-04-hanbury...ch-remote.html
"In a paper, published in Science Advances today, the researchers demonstrate that for light from a source such as the Sun, random fluctuations of intensity give rise to correlations of twisted light beams. (...) "Twisted light is all around us and occurs naturally," said Omar S. Magaña-Loaiza, first author of the study and a Ph.D. student in Boyd's team."

Do you still believe in the constancy of the speed of light, Einsteinians? If you do, here is more information for you:

http://rt.com/news/225879-light-speed-slow-photons/
"Physicists manage to slow down light inside vacuum (...) ...even now the light is no longer in the mask, it's just the propagating in free space - the speed is still slow. (...) "This finding shows unambiguously that the propagation of light can be slowed below the commonly accepted figure of 299,792,458 metres per second, even when travelling in air or vacuum," co-author Romero explains in the University of Glasgow press release."

http://www.upi.com/Science_News/2015.../1191422035480
"The speed of light is a limit, not a constant - that's what researchers in Glasgow, Scotland, say. A group of them just proved that light can be slowed down, permanently."

http://www.gmanetwork.com/news/story...ut-touching-it
"Although the maximum speed of light is a cosmological constant - made famous by Einstein's Special Theory of Relativity and E=mc^2 - it can, in fact, be slowed down: that's what optics do."

https://www.youtube.com/watch?v=NxJ7_tbbIsg
"Glasgow researchers slow the speed of light"

http://www.cbsnews.com/news/faster-t...peed-of-light/
"For generations, physicists believed there is nothing faster than light moving through a vacuum -- a speed of 186,000 miles per second. But in an experiment in Princeton, N.J., physicists sent a pulse of laser light through cesium vapor so quickly that it left the chamber before it had even finished entering. The pulse traveled 310 times the distance it would have covered if the chamber had contained a vacuum. Researchers say it is the most convincing demonstration yet that the speed of light -- supposedly an ironclad rule of nature -- can be pushed beyond known boundaries, at least under certain laboratory circumstances. (...) The results of the work by Wang, Alexander Kuzmich and Arthur Dogariu were published in Thursday's issue of the journal Nature."

http://www.nature.com/nature/journal.../406277a0.html
Nature 406, 277-279 (20 July 2000): "...a light pulse propagating through the atomic vapour cell appears at the exit side so much earlier than if it had propagated the same distance in a vacuum that the peak of the pulse appears to leave the cell before entering it."

Pentcho Valev
 




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