Posted November 26, 2014
DRM_free_fan: 1. Maths/Philosophy
It is impossible to have an infinite past. Absurdities would result if you were to have an actual infinite number of things. Since an infinite past would involve an actual infinite number of events then the universe must be finite - and therefore have a beginning.
IAmSinistar: Nothing precludes an infinite number of events. Indeed, even an infinite number of unique events are plausible. Though given the fractal nature of the universe, most events are subtle variations of a subset of truly unique events. Much in the same way most sunflowers are structurally identical but minutely distinct, so too are the events. It is impossible to have an infinite past. Absurdities would result if you were to have an actual infinite number of things. Since an infinite past would involve an actual infinite number of events then the universe must be finite - and therefore have a beginning.
I am not aware of a standard argument, Aristotelean or otherwise, that requires the universe to have a fixed number of events. Please elucidate.
The idea of an actual infinity is just conceptual. It's not descriptive of what happens in the real world. I can illustrate this if you want more detail.
Or put it another way - IF the past were really infinite then that would mean we have managed to traverse an infinite past to arrive to today. That's like somebody managing to count down all of the negative numbers and to arrive at zero at this second. That's absurb. Therefore there must have been a beginning to the universe.
DRM_free_fan: 2. Science
The universe is expanding. If you were to go back in time, the universe would decrease until a point where it didn't exist.
IAmSinistar: Incorrect, as this assumes a persistent state model that conforms to current normatives, and we already know this is not the case. Indeed, the first few seconds following the Big Bang saw universal laws and constants which vary from those we now experience. There is no reason to assume that the universe did not exists as a superdense singularity for as long as one cares to measure, before whatever shift caused it to erupt. The universe is expanding. If you were to go back in time, the universe would decrease until a point where it didn't exist.
To use a simplified parallel example, take the explosion of a stick of dynamite. If you measure the outward pressure and distribution of matter, and then attempt to reverse it with no other mitigating calculations, you would erroneously trace the explosion cloud back to a simple mathematical point that sprang from nothingness. But instead we know that it does have an origin, and an measurable one, just as the universe does. And just like with the universe, our measurement of the expanding cloud of dynamite gives us no information as to how long it sat there before exploding. We only know what we can glean from that single event forward.
Being serious again - I take it you prefer the Hawking model of the Big Bang theory over the more common theory of the Big Bang having a starting point?