On Sun, 5 Jun 2011 12:14:54 -0700 (PDT), the following
appeared in sci.skeptic, posted by Brad Guth
:

On Jun 5, 9:38*am, Bob Casanova wrote:
On Sat, 4 Jun 2011 12:07:23 -0700 (PDT), the following
appeared in sci.skeptic, posted by Brad Guth
:

On Jun 4, 11:40*am, Bob Casanova wrote:
On Fri, 03 Jun 2011 18:23:12 -0700, the following appeared
in sci.skeptic, posted by John Smith :

snip

...we will never know how radio waves (or any other waves, for
that matter) transverse and are propagated by the ether though space.
EM radiation doesn't require a propagation medium.
What's the all-inclusive population or average photon density per
given km3 of ISM, or better to know that of the IGM? (I'm talking of
accounting for everything from at least EIR/ELF [1km] to those
extremely hard Gamma of .001 nm)

Damfino, but Google is Your Friend.

And what's the relevance?

So, how many photons per km3 is there way out between the galaxies and
all them stars?

See my comment and question above? Did you somehow miss
their meanings?
--

Bob C.

"Evidence confirming an observation is
evidence that the observation is wrong."
- McNameless