The story of how the universe has evolved is somewhat long and I've discussed some of the details previously on d2jsp; for now it will probably suffice to point anyone curious to one of Stephen Hawking's or Brian Greene's books on the subject
If anyone has any questions about it, please feel free to PM me. I will touch on some leading ideas below.
Quote (Wacko @ 3 May 2012 16:33)
inb412pagethreadofheatedreligionbattles
on topic: agnostic...waiting for proof of why im here
I actually wanted to post to address this post. The idea of proof of why any of us exist is somewhat odd, if only because it asks a 'why' question when a 'how' question is probably a better investment. Presumably the
meaning of lif eis whatever we make it--we have a choice about what purpose we may ascribe to our own lives. How we got here is a question that begins to be resolved by followed the human genome backward in time as humans generally moved out of Africa just before mixing with Neatherthal and another species to the East. Before that we were basically huddles in Africa for quite some time, evolving from simpler forms of the genus
homo. Before that, our much earlier relatives included lemur-like creatures; and, much earlier than that, we descended from fish. Actually, our lungs evolved from gills, and or arms and legs evolved from fins. All creatures with spinal columns have a common ancestor, hence the phylum
chordata. Alas, even such complex creatures as early fish and fish-like creatures evolved from stuff that practically oozed out of the cambrian period--it's likel ythat virtually all animals came from sponge-like creatures. And, as we devolve backward in time, our older and older ancestors came from simple organisms, which in turn emerged out of a primordial stew, made up of mixed amino acids and tar-like susbtances. Proteins and chemicals combined to form this early muck.
The rest of the short version of our history is essentially lost in space. First, it seems there were quantum fluctuations that eventually caused the Big Bang, from which incredible energy blasted into (and creating) space and time; initially, even time was so compressed that it was essentially a spatial dimension. The three-dimensionality of our (experienced) universe is due to the Big Bang, but we could have had a different type of universe altogether. We just got lucky, and luckier still that our universe enables the stable formation of certain elements, including hydrogen, helium, lithium, and carbon (some of the oldest elements). We're also lucky that forces developed early on, and that our universe has a relatively (but not perfectly) balanced density. This enables the formation of stars, and, consequently, the formation of heavier elements and even planets ... and, eventually, the conditions required for life.
I hope that was somewhat helpful, even if it's just a very brief summation of a rather complex story. And yes, of course, I know about M-theory and how we don't have just 3-D space and time. My point is that our particularly human story requires 3-D, because otherwise the stuff that makes us wouldn't hold together.
This post was edited by RewtheBrave on May 4 2012 04:54pm