For the duration of this discussion I'll drop my usual memetic utterances. Prepare to be bitch-slapped.>>12No, a singularity is a point in some space where some parameters become infinite or undefined.
Yes, that's because
it's another spacetime, which means those parameters are different. It's really a tautology.
Hence, our universe is a singularity. But since we can't see 'outside' of it, given the restriction of the visible universe, we don't really know. We merely
propose that our universe is expanding inside a superspace that's either truly empty or has other characteristics. Our universe may well be expanding inside an empty but similar spacetime where
fundamental constants are the same, meaning our visible universe may not be a singularity with respect to that superspace. But that just brings up the issue that that superspace
is a singularity for what contains it, and since we're essentially the same sort of space, then by extension, our superuniverse is a singularity.
You can't really get around the issue. It's not even a good try, what you're doing.
There is no physical evidence for a "Big Bang".
Utterly wrong. The universe is clearly expanding and cooling, with a lot of visible evidence thereof. Read a book for a change, idiot.
let alone explain what "dark matter" [...] is
There are a variety of perfectly reasonable (i.e. classical-physics) explanations for DM. These explanations can even be collective. The major candidates for DM are WIMPs and MACHOs; basically, huge amounts of pervasive but nearly massless particles, and massive objects populating our galactic halo. The search for DM involves
precisely those targets. We search for low-mass particles (
which by definition are hard to find, since they must mass-interact with our equipment) and we search for things like singular black holes, neutron stars and white dwarves in the galactic halo (
which by definition are hard to find, since they're solitary and only show themselves directly via collective gravitation or the occlusion of starlight).
You're out of your league, son. Give up now and I'll only let you off with a few punitive thumps.