What is the largest number one could fit in the universe?

Answer 1

This question should probably be re-worded because it doesn't ask specifically what is to fit in the universe nor how we are defining the universe. However, we can define the known universe and then provide some concept of how many things can be fit into it. The following may not be entirely precise, but it can serve to help answer the question. Since the universe is expanding, the farther-away things are from us, the faster they are moving away. If they are far enough away from us, objects in the universe will be moving away at the speed of light. Since nothing can exceed the speed of light, we can define this distance as the radius of the "known universe". Now we have three other things to define, Neutrinos, goggle and googolplex. Neutrinos are so small that they have zero rest mass, for our purposes we will consider that they are the smallest particles. We all know that atoms are unimaginably small and that atoms are made-up of electrons and protons. An electron is less than one-millionth the size of a Hydrogen atom (the smallest) and a neutrino is still infinitesimally-small when compared to an electron. A goggle (not the search engine) is a large number defined as 10 to the 100th power (1 followed by 100 zeros). A googolplex is even larger and defined as 10 to the goggle power; 1 followed by 1 goggle zeros. Given all of this, the best answer I can provide to the original question is that if you were to pack neutrinos as tightly as possible (hexagonal packing) into the known universe, the number of neutrinos would be greater than a goggle, but less than a googolplex. Finally, I must mention the enormity of these numbers. If we look at numbers like 10 to the 40th and 10 to the 50th, we might feel that they are sort-of in the same ballpark--they aren't. The relationship between those numbers is the same as that between 1 and 10 billion. A goggle is so large that it is of little use for most purposes. Infinity, plus one. There is no such number. You can always add one.

Answer 2

Answer 1. Googolplex. Googolplex is googol (one hundred zeros (one hundred and one digits)) to the power of googol, googol times. If printed like an ordinary book, it wouldn't fit in the known universe. Of course it could always get bigger, googolplex to the power of googolplex, googolplex times would be rather large.

Answer 2. The largest number in the universe is inconceivable. However large you make a number you can always add 1 to it. But if you think of your universe as a sphere or an infinity ribbon, then you can imagine a sequence of numbers from some point in your universe which will end back at your starting point; regardless of how many numbers you conceive. Therefore, the largest number in the universe may also be also the smallest, i.e the next number after the largest number in your sequence, e.g. 1 or 0. Alpha and Omega.