jacob navia wrote:
BluMax wrote:

I have always wanted an answer that I can understand to the following
question.

Simply asked, "What is our Universe expannning into"?

Please explain it assuming I am an *ordinary* 13 years old.

I finally found this question and its answer, in a FAQ called
"Frequently Asked Questions in Cosmology":

http://www.astro.ucla.edu/~wright/cosmology_faq.html

It is all "%^$@^$%@^" to me. :-(

Thanks in advance to "anyone/everyone" who can explain it to
me so that I understand.

BluMax

Hi BluMax
Objects in space, in our normal space, grow by taking
*more space*.

Wrong. They do not grow *by* taking more space. It's the
other way round: *because* they grow, they occupy more space.


But for Space itself to do that, Space must take more of
Space, and in order to do that, Space must be larger than it is.

Non sequitur. Why should space behave in the same way as objects
in space?



Hence, the notion of space expansion is self-contradictory
and can't exist.

No, it isn't. Perhaps you should look at the actual equations
of GR and the math behind it (Riemannian geometry) instead of
relying on poor analogies, don't you think?


There can be no expansion of Space itself,
only of an object in Space.

Starting with a false premise, you can arrive at any conclusion
you like...



Your intuition is 100% right BluMax, do not let the talk lead you
astray.

Intuition is very often misleading in physics. My intuition tells
me also that the sun goes around the earth, that heavy things fall
faster than light ones, and that when I shoot particles at two
slits, they will go only through one of them.


Furthermore, there is no such thing as the Universe.

Ouch.


The Universe denotes no special object; in fact, it denotes no
object of any kind.

Beside "everything there is", you mean?


The fact that all things have a cause

Even that is not right. What is the cause of the decay of
an unstable particle? (please note that "its instability" is
not in any way a sufficient answer)


does not mean that the Universe has a cause any more than the
fact that all men have a mother means that Humanity has a
mother. Hence the Universe does not have a cause.

Non sequitur. The only logical conclusion you can draw is
"the universe does not need to have a cause". It does *not*
follow that the universe indeed has no cause.


The Universe does not have an age.

And that follows even less.


The universe is a short hand, comprehensive reference
to all things that exist.

Just above you said "there is no such thing as the Universe".
So you want to said that "there is no such thing as 'all things
that exist'"? Interesting statement.

Or do you want to quibble now that in one case, you wrote "Universe" and
in the other only "universe"?


And things being many, they have many ages. Hence, there is no
such thing as the age of the universe,

This is sophistry. And rather bad sophistry even.


unless we mean an
...average age. The Universe is just an inventory word, an
inventory meant to be exhaustive. And inventories have no
size. (I guess.)

You mean that we can't assign a size to the collection of
"all things which exist"? Why not?


Hence, the universe has no size either.

Again, starting from a false premise...



References:

Apeiron, Vol 10 Nr 1, January 2003
"A Bang into Nowhere"
Constantin Antonopoulos
National Technical University of Athens

Does Antonopoulos also use such strange arguments as the one
you presented above?


Bye,
Bjoern