I was waiting for someone to use the 2nd law argument, one of my favourites.
And yeah I realise Synik has already answered these with very valid arguments I just feel cheated because he got there first so I'm doing it too, not trying to steal your thunder or anything haha.
If this argument were valid, mineral crystals and snowflakes would also be impossible, because they, too, are complex structures that form spontaneously from disordered parts.

The Second Law actually states that the total entropy of a closed system (one that no energy or matter leaves or enters) cannot decrease. Entropy is a physical concept often casually described as disorder, but it differs significantly from the conversational use of the word.

More important, however, the Second Law permits parts of a system to decrease in entropy as long as other parts experience an offsetting increase. Thus, our planet as a whole can grow more complex because the sun pours heat and light onto it, and the greater entropy associated with the sun's nuclear fusion more than rebalances the scales. Simple organisms can fuel their rise toward complexity by consuming other forms of life and nonliving materials.
Because as a species moves around the world, or even just a continent, it is presented with different surroundings.
Even when the surroundings are very slight, there are variations.
Also, there is "chance evolution" which means that if there are two exact same creatures and one colony splits off to live in isolation but doesn't move to where the environment is different at all, they may, over a long period of time of course, still evolve in different ways that may or may not be beneficial to their survival, it's just change but without purpose behind it.

Of course decay rates can change according to the chemical environment, but for one thing when we look back to a billion years ago Earth wasn't much different chemically to what it is now.
Secondly, the difference in a different chemical environment isn't so significant that it would cause our data to be irrelevant. Notice that we say something is "circa 1,000,000,000 years old" not "1,435,733,005.342" years old.

I have a big problem with the idea that there are infinite universes. To me it falls victim to a fatal flaw.

That flaw is that the concept of infinity cannot be applied to finite things. There are far too many contradictions, and broken mathematical laws in trying to do so. In order to avoid these contradictions each universe would have to be infinite itself; which would only lead to further flaws, contradictions, and broken laws (of physics, mathematics, etc). Infinity is just a concept that has no real application to the finite universe we live in.

I would like to share a quote with you from a text relating to the impossibility of an infinite universe. It also applies to your question; who made God?

"None of the arguments forwarded by philosophical naturalism - (1) the universe is merely an illusion; (2) the universe sprang from nothing; (3) the universe eternally existed - satisfactorily account for the existence of the universe. Logically we can only turn to the possibility that God created [it]. If that's the case, however it immediately brings up the question - Who made God?

First, unlike the universe, which according to modern science had a beginning, God is infinite and eternal. Thus, as an infinite eternal being, God can logically be demonstrated to be the uncaused first cause.

Furthermore, to suppose that because the universe had a cause, the cause of the universe must have had a cause simply leads to a logical dead end. An infinite regression of finite causes does not answer the question of source , it merely makes the effects more numerous.

Finally, simple logic dictates that the universe is not merely an illusion; it did not spring from nothing (nothing comes from nothing; nothing ever could); and it has not eternally existed (the law of entropy predicts that a universe that has eternally existed would have died out an "eternity ago" of heat loss). Thus, the only philosophically plausible possibility that remains is that the universe was made by an unmade cause greater than itself."
Hank Hanegraaff

If one were to give any weight to the numerous new theories being released and worked on, most of which are variations on string theory and include multiple dimensions, then it would be possible to have a finite Universe that rebirths at a finite interval infinite times.
For instance one up-and-comer states that the big bang may have been caused by a collision which occurs circa every trillian years between higher-dimensional objects.
This is called the ekpyrotic model. Of course it poses serious questions toward the singularity, and many other unanswered questions, but it's one example of how there could be infinite Universes without necessarily defying basic mathematic laws.


Like I said before, this Universe can still've had a beginning, but it's more like a re-beginning. Of course cyclic Universe theories are nothing new, they've been around since at least the 1930s, but it's only since the 1990s that large advances have been made that make them possible.


Yes it would only make the effects more numerous. So instead of following these effects as best we can, we should just give up and say "God did it"?


Yes of course the Universe is not an illusion. And in this stage of re-birth it has not been infinite, roughly 13.7bn years to an accuracy of 1%.
However it's cycle may well be infinite.

Say you walked out of your house and saw a new car in your driveway with a ribbon wrapped around it. You could assume that it just happened to be there - that it just popped into existence. You can't entirely rule that out; it is still (for the severe lack of a better word) possible. But probable? Well, that's a whole different arena. You would be much more likely (and exceedingly more rational) to assume that your wife, who said she got you something special for your birthday, bought it for you and surprised you with it.

That's not a good analogy, please feel free to read more on Natural Selection to see why that analogy doesn't work.
Wikipedia is a great place to learn about all this.