Re: Exact value of Hydrogen line?

Ulf Torkelsson wrote:
Richard Saam skrev:
Ulf Torkelsson wrote:
Richard Saam skrev:
Are any electromagnetic astrophysical waves observed below 5 E-5 Hz ?

The typical plasma frequency of the interstellar medium is on the order of some kHz, which means that electromagnetic waves of lower
frequency will be rapidly damped out. Of course, any observatory that we build will at least be located inside the solar wind, and usually even inside the Earth's ionosphere, where the plasma frequency is even higher (MHz in case of the ionosphere), which sets the lower limit on the frequency of astrophysical electromagnetic waves that we can
observe.

Ulf Torkelsson

Yes, there are these plasma frequencies as you describe but:
What is the 'rapidly damped out' time of other incident frequencies
and can this dampening be used as an observational tool?

The electromagnetic waves become evanescent below the plasma
frequency and are damped out within at most a few wavelengths or periods
if you prefer to think in terms of the time scale. For that reason
there is no way of observing these waves from an astrophysical source.
Having said this though one should keep in mind that there are other
forms of waves that can propagate through a plasma at a frequency below
the plasma frequency, for instance Alfven waves. Such waves can be
measured in situ in the magnetosphere and the solar wind.

One should also keep in mind that although one cannot have an
electromagnetic wave at a frequency below the plasma frequency it is
possible to observe slow modulations in waves with higher frequencies,
which is the way a radio works.
Assuming there is some type of ~1E-5 hz astrophysical generator
(dark matter and/or energy as in post 'hypothesis for dark matter'),
do we see these plasma frequency damping out effects
on a complementary frequency order of 1E-5 hz (or harmonics thereof)
in accordance with the following observations:

Assuming some new physics you can always explain any observation that
you want to explain, but most of the time the same phenomenon can also
be explained by more mundane mechanisms that are based on established
physics. As far as I can tell essentially all of the observations that
you list can be explained in the latter way, and sometimes it is even
possible to find more than one explanation based on conventional
physics, because there is insufficient data.

***D. Saul Davis, Paul Hickson, Glen Herriot, Chiao- Yao She Temporal variability of the telluric sodium layer Science 24 http://arxiv.org/abs/astro-ph/0609307

***K. Pounds , R. Edelson, A. Markowitz, S. Vaughan X-ray Power Density Spectrum of the Narrow Line Seyfert1 Galaxy Akn 564, http://arxiv.org/abs/astro-ph/0101542

***Kotov V.A., Lyuty V. M., Haneychuk V. I. :
"New evidences of the 160-minute oscillations
in active galactic nuclei", 1993,
Izv. Krym. Astrofiz. Obs., Tom 88, p. 47-59.

***Interstellar scintillation of AGN
http://www.jive.nl/science/iss.html

***Kiwamu Nishida, Naoki Kobayashi, Yoshio Fukao Resonant Oscillations Between the Solid Earth and the Atmosphere Science 24 March 2000 Vol. 287. no. 5461, pp. 2244--2246

and perhaps these damping effects result in tidal forces
of a magnitude to affect planetary flybys:

***John D. Anderson, James K. Campbell, Michael Martin Nieto,
The energy transfer process in planetary flybys http://arxiv.org/abs/astro-ph/0608087

and cause the anomalous Gravity Probe B Polhode motions of superconductor
supercurrents:

***Gravity Probe B Gyro #1 Polhode Motion Animations
http://einstein.stanford.edu/Media/Polhode_motion-animation.html

The last two examples illustrate another problem. These are small
effects in highly complex experiments, which are also influenced by the
environment in a number of different ways, which might not even be
completely understood by the experimentalists themselves, since they
only have a limited knowledge of and control of the environment
surrounding their instruments.

Ulf Torkelsson


On the subject of Alfen_wave:

http://en.wikipedia.org/wiki/Alfven_wave

"The ion mass density (ni mi) provides the inertia
and the magnetic field (B) line tension
provides the restoring force."
such that:

v = B / sqrt(4 pi ni mi)

v = velocity
B = magnetic field
ni = ion number concentration
mi = ion mass
mu = magnetic permeability
then:

mi v^2 ~ B^2 volume / (4 pi)

To which Enrico Fermi in 1949 nodded his head exclaiming "of course".

Eugene Parker
"Conversations on Electric and Magnetic Fields in the Cosmos
(Princeton Series in Astrophysics)"
does not say 'of course' could be applied
to an analogous argument for
an electric field (E) and its displacement (D) in that same 'volume'

mi v^2 ~ D E volume / (4 pi)

But if electric fields (E & D) as well as (H & B)
were involved as restoring forces,
all of the examples could be explained
in terms of gravitational tidal effects related
to a significant portion
of the observable universe critical mass (~1E56 g)
(dark energy dark matter?)
oscillating in accordance with these restoring forces
at ~1e-5 hz with a related van Alfen wave mechanism

As an aside, Eugene Parker makes a strong case
for the cgs system use in research analysis
because dimensional units are the same for E,D,H & B
(g ^ (1/2) cm ^ (-1/2) sec ^ -1)
and can be compared on that basis,
an attribute that does not exist in the SI system.

Richard D. Saam


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