Step two) Within this infinite universe, where is Earth located?
We know the universe is vast, but has science proven the cosmos is infinite?
When I asked this question I had "no" as the answer simply because the universe is made up of real matter and all real matter is finite.
Is the cosmos infinite? well it doesn't really have any choice, it has to be! If there was a barrier of some kind, then what is beyond the barrier? nothing? oh wait, there is already plenty of that on this side!!
I am afraid it doesn't. Everyone I know of is in agreement that the universe is expanding and until it decides to stop, it is infinite.
Check out this website: http://www.thekeyboard.org.uk/What%20is%20infinity.htm
Here are a few of the first paragraphs...
We often here the terms 'infinite' and 'infinity', sometimes used in connection with the size of the universe, such as an infinite universe for example. The terms more properly belong in the world of mathematics, where for example we may have an infinitely long string of numbers as the result of a calculation, such as pi. The terms are very real to mathematics, but can anything real, not theoretical, be infinite?
Naturally in mathematics we can have infinity, numbers go on for ever, but numbers are not real, they are abstract. I cannot imagine anything 'real' that we could apply an infinite number to.
Strictly speaking, according to Einstein's Theory of Relativity, a singularity does not contain anything that is actually infinite, only things that MOVE MATHEMATICALLY TOWARDS infinity. A black hole is formed when large stars collapse and their mass has been compressed down to a very small size and the powerful gravitational field so formed prevents anything, even light, from escaping from it. A black hole therefore forms a singularity at its centre from the concentrated mass of the collapsed star itself and from the accumulated mass that is sucked into it. A singularity's mass is therefore finite, the 'infinity' refers only to the maths.
Can we have an infinite universe for example? The answer is no, the universe is finite. Stephen Hawking in 'A Brief History of Time' (1989 page 44) describes the universe as being "finite but unbounded". The simplest answer is that as the universe is known to be expanding, it cannot possibly be infinite. To be precise, the dictionary definition of the word universe is "all that is. The whole system of things." In this sense the universe is not expanding into anything other than itself, for whatever it is expanding into is part of the universe, there being nothing else but the universe. However, for the sake of simplicity, I am referring only to our Big Bang expanding universe as 'the universe'. (Even if you happen to disagree with the Big Bang theory, the term 'universe' will still have the same meaning here, as it refers to 'our' universe only, and does not include whatever may or may not exist outside of it.) I will try and explain a finite universe as some people understandably have problems with it.
A good place to start is to understand the very real difference between infinity and a large number.
Because infinity is not a number, large numbers are no 'nearer' to infinity than small numbers. Number 1 billion for example is no nearer to infinity than number 1, because the two, numbers and infinity, are in no way related. It is then impossible to approach infinity, a thing is either infinite and immeasurable, or finite and measurable, it cannot be part way towards infinity. Imagine running up a 'down' escalator, never moving forward. If you run for a week you are no nearer reaching the end of the escalator than if you run for a minute, you cannot get any closer to something that has no end.
An infinite universe for example would exist in every direction forever, there could be nothing else, ONLY the universe. It is then very easy to understand why our universe cannot be infinite, it is because it is expanding. It cannot be both infinite and expanding. It could be infinite OR expanding, but CANNOT possibly be both, that is a contradiction in terms, and we do know it is expanding.