Quote from: BadBear on December 02, 2013, 09:46:35 AM

Here's some good reading about address collisions/exhaustion.

https://bitcointalk.org/index.php?topic=3462.0;all
https://bitcointalk.org/index.php?topic=27277.0;all
https://bitcointalk.org/index.php?topic=26278.0;all

Quote from: theymos on February 14, 2011, 11:23:15 PM

If every person on Earth makes ten addresses per second for 20 years (2x10¹⁸ total addresses), then the probability that two of these addresses collide is about 1.57x10^-12.

Quote from: Gavin Andresen on February 19, 2011, 08:12:37 PM

Quote from: david19801 on February 19, 2011, 08:06:22 PM

A committed individual or organization could easily aquire network storage in the Petabytes. I think that would be more than enough to get a sizable operation started.

1 petabyte is 10¹⁵ bytes.

There are 2¹⁶⁰ possible BTC addresses, each of which is 160 bits == 20 bytes long.

So to store all of them you need 2¹⁶⁰x20 bytes, which is 29,230,032,746,618,058,364,073,696,654,325,660 petabytes.

Quote from: ribuck on February 19, 2011, 08:36:41 PM

Quote from: david19801 on February 19, 2011, 08:21:19 PM

Bear in mind, we are not looking for a single address among the clouds here. We are looking for -any- address containing BTC.

Suppose each of the 7 billion people in the world has 1000 unspent addresses. On average you would need to try more than 10³⁵ addresses to find each spendable one. Suppose you can check a million addresses per second, this is going to take you more than 10²¹ years.

If everyone in the world is trying to crack this at the same time, it will still take around 10¹² years. And when someone finally cracks it, after paying the electricity bill for 10¹² years, they might be disappointed to find that the key unlocks just 0.05 BTC from the Bitcoin Faucet. Even if it's ten million bitcoins, it's not going to pay the electricity bill for 7 billion computers running for a trillion years.

In short, don't worry about it.

Sorry for digging up an old thread but how can we be certain that this many bitcoin addresses exist if we are not able to generate and store them? Are most bitcoin addresses just theoretical?