Re: Dark Matter, dark eneggy, & conservation

From: Joao Leao <jleao.domain.name.hidden>
Date: Sun, 2 Nov 2003 22:05:51 -0500

On Nov 2, 2003, at 5:16 PM, Ron McFarland wrote:

> Greetings list members. This is my joining post.
>
> Recent headlines indicate that there is empirical evidence now that
> our known universe is about 13 billion years old, it is essentially
> flat, and that space/time continues to be inflationary (we are in a
> continuing big bang state) after experiencing an initial expansion
> phase originating from a singular point -- followed a few billion
> years later by some sort of phase change that cause the universe to
> change from a slowing down expansion rate to a speeding up expansion
> rate. The properties of "dark energy" are postulated now to be the
> cause of continued and ever increasing in rate expansion of
> space/time, the continuing big bang state.
>
> The properties of dark matter are postulated to be the cause of
> observed gravitational interactions within the universe as a whole
> and where there is insufficient observable "normal" matter to account
>
> for the observations. Dark matter is now said to greatly exceed the
> amount of matter that we are able to measure and verify as existent.

Ron

I am sorry but you seem to contradict yourself below!
You state, quite correctly as far as I can tell, what the
outcome of the most recent cosmic observations on
our universe is. But them you state that

>
> Neither dark energy nor dark matter has been proven by experiment or
> measurement to exist. Both seem as pure postulates at this writing.

Both "dark matter" and "dark energy" express little more than our
puzzling
with two sets of consistently observed effects which we aren't able to
accommodate in the so-called "concordance model" of standard
cosmology. What these terms designate are not (yet) definite entities
so it is a bit early to even call them postulates. Theorists have sought
to explain these effects along several distinct hypothetical lines but
the word is still out on which one of those will prevail.

>
> To me, dark energy seems to be the more important postulate. It
> appears to me that if the universe will forever keep expanding at an
> ever increasing rate then within a non infinite time period no
> elementary particle of matter will be able to interact with another.

What makes you think so?

> That condition seems to indicate that relativity would thus be
> meaningless when that point in time occurs. To my logic this argument
>
> appears to violate conservation of energy law. If the argument is
> nonetheless true, then it follows that said law is not a real law and
>
> that our entire theory structure is faulty at a fundamental level.

That may very well be the case but it is again, to early to tell. As you
have probably heard General Relativity has always had an "open
place" for something like Dark Energy, namely the cosmological
term. So it may be worth our while to re-examine its implications.
If our Universe is already dominated by Dark Energy as it seems
than the continued acceleration may very well express the peculiar
de-localization of energy that made GR suspect for so many years.

>
> I would be most pleased to here read comments from the list members.
>
> Ron McFarland

Thanks for a very lucid and current question, though. Not many of
those pop up here...

Kindly

-Joao
Received on Sun Nov 02 2003 - 22:05:37 PST