(photons hit eye) I
think we are talking about the
same thing here, in different ways. Your point about
the light from distant sources getting vanishing small
is what I am making in my discussion of infinite sums.
From what I understand, while any one light source
would vanish from long enough away, IF there was
an infinite source of them, each of the tiny points
from them would add up enough in our eyes to
make the night sky look like day.
That is, unless an assumption is wrong – the universe
isn’t infinite or isn’t infinitely old & thus light from
more distant stars hasn’t had time to reach us.
Or another way of looking at it is:
Q: Why is the night dark?
A: You just answered it
Or rather, if the night sky ISN’T dark, then we won’t
be around to wonder about it (i.e. Anthropological Cosmology).
After the big bang, for millions of years there was no dark sky
-- but it was too hot for creatures such as us. And you can
make similar arguments for possible ultimate fates of the
universe.
(dark matter) I was referring to “ordinary” matter in the
clouds between us & the center of the galaxy. As I understand
it, Dark matter does not interact with other matter (or forms
of energy such as light) except through gravitation. So if there
were Dark matter clouds between us & the center of the galaxy,
we could not tell, unless we detected gravitational affects.
Gravity is incredibly weak (it may not seem so when
stepping off a cliff, but remember the whole earth
is pulling there). Every time you lift a beer off the
table demonstrates how much more powerful other
forces are (puny muscles beat gegabazzilion tons
of the earth’s gravity!
)
In any case, light could blow through any Dark matter
without any problems, unless it was hugely massive.
(& from what I’ve read, most is thought to reside
in halos around galaxies or between galaxies in
clusters).
(fractal dimensions) “Chaos” was a great book.
I believe that is where I 1st saw the concept of
fractal dimensions.
Let me know if below is more detail than you want
to know. I will add in the next post what I understand
of fractal dimensions if you want.
I’m not sure if you ever covered multi-dimensional
spaces in your math classes (I never did till college),
but I was surprised that it was a fairly “natural” extension
of concepts of HS algebra.
The idea was that, for instance 2D you could give x & y
coordinates for anything on the plane. For 3D you
could give x, y, z coordinates for anything in ordinary
space (x could be Left-Right, y forward & back, z
up & down).
For 4D you could give w, x, y, z coordinates for anything
in the 4D space, 5D v, w, x, y, z coordinates, etc. There
is no way I can visualize higher dimensional spaces
(except maybe if I’ve had enough to drink
)
but its possible to algebraically manipulate them.