Luigi Caselli wrote:

"Bjoern Feuerbacher" ha scritto nel
messaggio ...
Luigi Caselli wrote:

But "rushing away" does cause a Doppler shift, does it not?

In the standard big bang theory Doppler shift is the reason for "rushing
away".

Sorry, but this makes no sense. Did you want to say:
"In the standard big bang theory 'rushing away' is the reason for
Doppler shift"?

If yes: that would make sense, but would be wrong nevertheless..

You're right (is the "rushing away" that creates Doppler shift), but why is
wrong?

That's a popular misconception about the cosmological red shift. It
isn't called by galaxies actually moving - it is caused by the space
between galaxies expanding.


In other less popular theories this is not so sure...

But big bang is so fascinating that almost noone has doubts about
strange
facts as a galaxy formed only 750 millions years after the big bang (a
bit too young)...

This is, AFAIK, consistent with the current view on galaxy formation.
Not a trouble for the current hypotheses.

I'm not so sure. See for example
http://www.cnn.com/2004/TECH/space/0...ind/index.html
Noone seems to have answer to a young galaxy supercluster like this one.

The crucial word here is *supercluster*, not "galaxy".

And IIRC, there was even an explanation for this find - the formation of
such large clusters at such an early time is not impossible, simply very
unlikely. We have found only one such big cluster so far at that early
time - only time will tell if there are more like that one. Only *if*
there are more, the current theories of galaxy and galaxy cluster
formation will be in trouble.


If there are problems to explain galaxies of 10,8 billion years ago how can
explain a so young galaxy (13 billions years ago).

The problem is not with explaining the galaxies. The problem is with
explaining how a *cluster* of galaxies (a big structure) could have
formed so early.


Maybe superultraspeed inflation?

No, that makes no sense. Are you sure you know what inflation means?


seen using gravitational lens...

Yes. So what?

No problem, only it's a bit funny to see multiple copies of the same object
due to gravitational lens...

Yes, that's kind of funny. Sorry if I misunderstood you - it seemed to
me if you thought this were some kind of problem.


some sort of great
illusionism like dark everything (matter, energy, holes, etc.) that we
discover day after day...

What's your problem with those?

I don't like claiming forces from nowhere to save any theory.

Dark Matter wasn't postulated simply because of cosmology - there were
several lines of evidence for it (galactic rotation curves and galaxy
clusters). For Dark Energy, there are two lines of evidence, too
(supernovae and CMBR); additionally, it is expected to be there based on
QFT.

And Black Holes weren't ever postulated to save any theory, so why did
you include them above?


But if I can believe Italian politicians I can believe everything...

One should never "believe" a physical theory. One should study it and
accept its validity based on the evidence.

There's no more evidence in cosmology, only indirect effects that you can
explain as you like...

Please present any other theory than the Big Bang which explains all the
observations. *Quantitatively*. Not with some vague hand waving.


For example:
Strange galaxy rotation? Introduce dark matter of the right quantity to
justify it (very easy).

First, galaxy rotation has nothing to do with cosmology. Second, as
mentioned above, there are several lines of evidence for the existence
of dark matter - not just one, as you seem to propose here.


Ultraspeed galaxy "rushing away"? Introduce dark energy of the right
quantity to justify it (very easy).

See above.


Search some less dark solutions? Too difficult and risky...

If you think this is possible, why don't you do it?

Hint: not all cosmologists accept the Big Bang theory (there was Hoyle,
there still is Narlikar, and so on). They have searched for
alternatives. So far, they haven't succeeded in finding one which
describes the observations so good as the BBT.

The argument "The BBT looks strange to me, I don't like it - surely
there is a better explanation somewhere, although I don't know which!"
doesn't look very convincing...


Bye,
Bjoern