The Earth is fla...
The Earth is fl...
The Earth is f...
Okay, I tried, and I just couldn't even jokingly say it. THE EARTH IS NOT FLAT. Sure, the North and South Poles may be slightly flattened, and the Earth is not a PERFECT sphere due to the force of its rotation, but it is NOT FLAT. Goddammit. That's like wackjobs saying the Sun and Moon are both hologram projections... Oh wait...
As for the whole Matrix idea, I don't know quite enough about it in particular to really understand exactly and specifically what it entails and implies, at the most basic level, to form a solid belief or disbelief in it, but from what I have read and learned about it, I definitely wouldn't personally instantly discredit and dismiss it as a possibility.
I personally, just for my own satisfaction and amusement, like to lean more towards the whole proposition of the Universe being a 'simulation' by a higher and more advanced being/beings. I know this particular theory has been, not necessarily flat out disproved but explained to be unlikely, but I still personally would choose this theory at least as my favorite if anything.
I also definitely like the theory/idea of the Universe being alive and conscious, and in a constant equilibrium, and in association with the Big Bounce Theory, the Universe constantly expanding and contracting like a heartbeat. At the quantum level and realm of existence, quarks also continuously 'pop' in and out of existence, and considering everything being relative, these particles could also possibly be Universes themselves in a multiverse, at such an atomically small scale relative to us they appear to be nothing more than point-like particles, but at their relative scale they could very well be universes themselves.