Posted on 11/19/2003 3:30:55 AM PST by Boot Hill
Explanation: Light is more complicated than we thought. When astronomers measure light, they are usually concerned with its direction, energy, and spin polarization (sometimes). Recently, however, it has been more broadly realized that photons can also have orbital angular momentum (OAM), an attribute classically analogous to the Earth orbiting the Sun as well as spinning on its axis. Pictured above, the wave-front of a photon with OAM is shown to be twisted, in contrast to the flat plane of zero OAM light. Light with OAM might be used to increase the information content of communication or to discern specific types of astronomical sources. Passing through a common lens, light without OAM focuses to a point, whereas light with OAM focuses to a ring. Most light bouncing around the cosmos, however, is expected to have so little (or zero) OAM that the created ring is too small to measure. Even given other promising methods for measurement, exploiting OAM for astronomical discovery might be as much an issue of observational practicality as theoretical possibility.
Holy Foot Candles Batman - Light has been taken over by the DemoncRATS!
Yes, it is amazing how all of man's discoveries about EM wave phenomena comport so exactly with Maxwell's equations.
--Boot
You know, I almost answered Buckhead that way, but then I realized I was responding less to his specific question, than to where I sensed he seemed to be heading with his query (a short lifetime universe).
While it is true that the current state of science regarding the red shift is that it is due to Doppler shift, nonetheless, one would be taking an imprudent step to translate that "understanding" to a non-scientific limit of "proven and irrefutable".
Since the phenomenon described in the thread article is so new and there is so little understanding of how it would be created in nature, or how an existing "normal" light beam could be "twisted" or how twisted light could be detected, distinguished and observed, it might be more prudent to be a bit more circumspect in regards to such answers.
For instance, in #13 above, I present one possible scenario with "twisted" light that could account for an apparent lowering of its frequency like occurs with red shift. Could this account for the observed astronomical red shift? It's possible, but while I don't think so, I also believe that it is still too early just to give a blanket "No" to the question.
--Boot
I need to look at this closer.
Your statement is incorrect. Frequency is intimately connected to the photon's momemtum because when a photon looses momentum, the result is a loss of energy. And the consequence of a photon losing energy, is a decrease in frequency, i.e., a red shift. See below.
momentum:
p = m*v
energy of a photon:
E = h*f = mc2
(where h = Planck's constant)
and by combining eq. 1 and eq. 2, we get the momemtum of a photon:
p = h*f/c
(where c = speed of light)
From eq. 3 it can be seen that if the photon's momentum (p) decreases, the frequency (f) must also decrease.
--Boot Hill
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