Quantum Computing and Bitcoin

[drb0n3z]

Excellent picture and explanations folks.

[lindatess]

That picture is misleading... Especially the counting part. You could go through all the numbers 2^256 across a lifetime if you wanted to with a computer that was fast enough. I think it would have to assume some kind of minimum period between the counts.

I don't believe it has anything to do with the total number of atoms or matter in the world. I'm pretty sure there are more than 2^256 atoms just on earth. Many times more in the universe.

[Bitcoinpro]

That picture is misleading... Especially the counting part. You could go through all the numbers 2^256 across a lifetime if you wanted to with a computer that was fast enough. I think it would have to assume some kind of minimum period between the counts.

I don't believe it has anything to do with the total number of atoms or matter in the world. I'm pretty sure there are more than 2^256 atoms just on earth. Many times more in the universe.

you could easily fill the entire universe with that many atoms the number is almost infinite in size

[Bono]

lol @ misleading

http://crypto.stackexchange.com/questions/1145/how-much-would-it-cost-in-u-s-dollars-to-brute-force-a-256-bit-key-in-a-year

https://i.imgur.com/pJcgpal.jpg

[Karasugoi]

That picture is misleading... Especially the counting part. You could go through all the numbers 2^256 across a lifetime if you wanted to with a computer that was fast enough. I think it would have to assume some kind of minimum period between the counts.

I don't believe it has anything to do with the total number of atoms or matter in the world. I'm pretty sure there are more than 2^256 atoms just on earth. Many times more in the universe.

you could easily fill the entire universe with that many atoms the number is almost infinite in size

While 2^256 is unthinkably large, I'm not sure we could "fill" the universe with this many atoms. 

Isn't 2^256  about 1.1579E +077 ?   

"Universe Today"  has the number of atoms in the entire observable universe estimated to be within the range of 10E +078 to 10E +082,  this doesn't even include the dark matter mass....

Read more: http://www.universetoday.com/36302/atoms-in-the-universe/#ixzz2pJVB892V
 

[greenlion]

Commercial quantum computers have been in use for a while: http://www.forbes.com/sites/alexknapp/2011/10/31/lockheed-martin-installs-quantum-computer/

The NSA probably have quite a few of the more advanced ones.

The D-Wave is not really a "quantum computer" in the conventional sense, it uses quantum annealing.

The practical problems related to actually implementing computational entanglement are absolutely ridiculous in scope, and at the end of the day, we really don't even know if the universe actually works in such a way to allow for this technology to exist as we envision it in the first place.