# Maths and the infinite universe.

Gold Member

## Main Question or Discussion Point

mathematics describes the universe.
in mathematics there are infinities.
therefore the universe is described by infinities- therefore the universe is infinite.

what is the flaw?

i think that the flow is that in mathematics there arent just infinities but it also has finite answers.

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Eh
Premise 1 is the problem. Math describes the universe, but also a countless number of worlds that don't actually exist. IOW, math can tell us about logically consistent universes, but not the actual universe we live in.

There has never been logical proof the universe is infinite.

FZ+
Amendment:

mathematics describes the universe. {imperfectly and incompletely}
in mathematics there are infinities. {as far as we know.}

Pick one of the curly brackets.

Gold Member
Originally posted by Eh
Premise 1 is the problem. Math describes the universe, but also a countless number of worlds that don't actually exist. IOW, math can tell us about logically consistent universes, but not the actual universe we live in.

There has never been logical proof the universe is infinite.
we dont know for sure that these worlds dont actually exist (there is multiverse interpetation of quantum theory which implies that these worlds actually do exist now if it's correct [i dont how you can proove it] then the maths that describes them is correct and therefore so is the multiverse is described by infinity]).

btw, im not a believer in multiverse idea.

Gold Member
Originally posted by FZ+
Amendment:

mathematics describes the universe. {imperfectly and incompletely}
in the brackets do you refer to the mathematics or to the universe?

i think you refered to the former, and in reply to that who are we to think that the universe should be perfect or complete (our understanding of the universe may be incomplete and so is the maths).
if maths describes the universe and it's incomplete it's because our knowledge is thus incomplete.

Gold Member
here's another try to proove that the universe is infinite (i think the flaw in here is that he cant disproove that the the universe is finite he just says it cant be proove for all we know the universe finite's is unconcluded).

the webpage with the proof:
http://www.micromike.com/cosmology/cosmosargument.htm

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Eh
Originally posted by loop quantum gravity
we dont know for sure that these worlds dont actually exist (there is multiverse interpetation of quantum theory which implies that these worlds actually do exist now if it's correct [i dont how you can proove it] then the maths that describes them is correct and therefore so is the multiverse is described by infinity]).

btw, im not a believer in multiverse idea.
Even if the MWI, not all logically consistent universes would exist. Only universe consistent with QM would.

Eh
Originally posted by loop quantum gravity
here's another try to proove that the universe is infinite....
the webpage with the proof:
http://www.micromike.com/cosmology/cosmosargument.htm [Broken]
All I can say is YIKES.

P1: There are two choices: The cosmos is infinite or it is finite.

Good so far.

P2: If I can prove that it can't be finite, then logically it must be infinite.

Good. No all one has to do is disprove the finite case...

P3: From set theory, for any set to be finite, the set must have a boundary.

Things are starting to fall in the toilet, because he's confusing sets with the geometry of space. In terms of geometry, one does not need a boundary or edge to define a finite volume. But even if we were to give him this by pretending to live 5000 years ago in the time of Euclid, the argument still falls apart below.

P4: Thus to prove a finite cosmos, one must be able to prove there is a boundary.

False, since P3 is invalid. But let's assume it's correct to this point.

P5: The cone of knowledge concept from philosophy and physics shows that we can never know all that exists.

Fine.

P6: Since we can't know all that exists we can never prove the cosmos has a boundary.

Ok...

Conclusion 1: Since we can't prove a boundary, we can never prove the cosmos is finite.

That follows.

Conclusion 2: Thus, the cosmos is infinite.

Conclusion 2 does not follow from conclusion 1, because all that has been established is that we cannot prove the universe is finite, not that the universe cannot actually be finite. Because a premise can not be proven, does not mean it's negation is automatically true.

I would seriously have to question the intelligence of someone capable of putting together such poorly reasoned drivel and thinking it to be valid.

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