Re: Dark matter/energy - is it real?


"Erik Max Francis" <max@xxxxxxxxxxx> wrote in message
news:cMqdnQYmbPxU-6zZRVn-pA@xxxxxxxxxxxxxxxx


As I pointed out, the dark matter hypothesis is really no different from
Fermi concluding that neutrinos existed. Were neutrinos fantasy too?



Neutrinos had an origin- they were created by the missing energy from
reactions.

Where does dark matter come from? It wasn't created in the big bang nor is
it created by any physical process we know of.



Dark matter is non-baryonic. Which is to say it isn't made of baryons.
Since protons and neutrons are baryons, dark matter isn't made up of
protons and neutrons.

That _is_ all that dark matter is. It's simply matter that is not glowing
that we assume is there because our gravitational theories are very good.


Except that our theories don't actually, you know, work.




There are reasons from the Big Bang model for thinking that this dark
matter is not baryonic, as you've pointed out above (and which I pointed
out in detail in the message you're responding to). But that is further
analysis, not based on a direct observation of the properties of dark
matter.


There are no direct observations of the properties of dark matter. No one
has seen even the smallest iota of any





We know it's non baryonic because we know approximately how many baryons
the big bang made. For baryonic matter to be the missing mass there
would have to be about ten times as many as the theory predicts.

I think it's interesting that you have absolute faith in our understanding
of particle physics, baryogenesis, and nucleosynthesis, but apparently
absolutely no faith in our theories of gravity.


We have observations that all confirm our theories of particle physics and
we have observations that contradict relativity.



Since you seem to think the nail in the coffin is that dark matter must
be non-baryonic, why not conclude that perhaps it's our understanding
baryogenesis that's wrong and maybe it's baryonic after all?


I have no reason to disbelieve particle physics. I *do* have reasons to
doubt relativity.




You can't have it both ways.


So our observations don't agree with the theory of relativity, but it's some
innocent bystanding theory that is actually at fault, via a mechanism of a
class of matter that has no properties but that shim the errors in
relativity?




That leaves another form of matter. But there's a huge hole in the
theory of dark matter- if the universe is mostly made up of it, where is
it? Why don't we see any on Earth? Why do no known physical processes
create it? It's not that it's undetectible- we would notice that energy
was missing from reactions (which is how we found the neutrino).

There is a perfectly good hypothesis to explain this; namely, that it is
composed of weakly-interacting particles.


Nope, the energy it is made of would be detected by it's absence.



Neutrinos, for instance,
behave exactly as you describe, and although they're quite weird compared
to normal matter, do not present any great difficulty to our theories of
particle physics.


Because we know where they come from. There's no place for dark matter to
come from.




Dark matter, if it exists and judging by the ways galaxies rotate, isn't
distributed right either. It would have to itself be unaffected by
gravity while affecting non-dark matter, but organize itself into halos
around galaxies for some unknown reason.

Dark matter is _obviously_ affected by gravity; why else would it be in
halos around galaxies if it weren't affected by gravity?



Why isn't it draw to the core of galaxies like other matter?





If it weren't
affected by gravity, then there would be a uniform distribution of this
dark matter throughout the Universe without respect to where the galaxies
are, which is not what we observe.


And if it were afftected by gravity it would be concented in the core of
galaxies, not in halos around them.



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