What are the odds we'll find a collision by the time the last bitcoin gets mined?

[TiagoTiago]

And can we add somthing on the clients to keep an eye for that?

[Jered Kenna (TradeHill)]

And can we add somthing on the clients to keep an eye for that?

Are you just curious or because it could have a really bad effect?

What would be the outcome anyways? Double spend?

[theymos]

A collision of what? Transaction hashes, block hashes, addresses?

The result will depend on how many items are created in that time. In any case, it's so unlikely that adding a check for it is a waste of time.

[SteveB]

I think that the remote possibility of address collision and the ever increasing need for fees are the two biggest obstacles to the wide acceptance of bitcoins. No one will trust bitcoin with any large transactions if there is even the slightest chance of an address collision.

[FreeMoney]

No one will trust bitcoin with any large transactions if there is even the slightest chance of an address collision.

False. I trust it.

I understand math though ymmv.

[SteveB]

No one will trust bitcoin with any large transactions if there is even the slightest chance of an address collision.

False. I trust it.
I understand math though ymmv.

Not everybody understands (or has the desire to understand) the math. I know that the chances of a collision is so small that it probably will never happen in a billion years. But try to tell that to some non geek.
Would you trust your money to a bank were the clerk just makes up an account number without checking if the number is already in use?

[theymos]

There are currently 329,993 addresses in the Bitcoin network. Say that this number of addresses are created every day for the next 140 years. That's 16,862,642,300 addresses.

The chance that at least two of those addresses collided is about 9.7x10^-29, using the formula here. Calculation.

[Dude65535]

Would you trust your money to a bank were the clerk just makes up an account number without checking if the number is already in use?

No but only because humans are really bad at producing truly random numbers.

[SteveB]

There are currently 329,993 addresses in the Bitcoin network. Say that this number of addresses are created every day for the next 140 years. That's 16,862,642,300 addresses.

The chance that at least two of those addresses collided is about 9.7x10^-29, using the formula here. Calculation.

I get that the chance is very, very, very  small. But unless there is no chance at all there is still a chance. All I am saying is that there should be a check to make sure that a new address does not exist already.

[FreeMoney]

No one will trust bitcoin with any large transactions if there is even the slightest chance of an address collision.

False. I trust it.
I understand math though ymmv.

Not everybody understands (or has the desire to understand) the math. I know that the chances of a collision is so small that it probably will never happen in a billion years. But try to tell that to some non geek.
Would you trust your money to a bank were the clerk just makes up an account number without checking if the number is already in use?

I can think of plenty of safe methods that don't involve checking all previous account numbers. One of them would be using really long random strings. Another would be adding 1 to the last issued number. I'd actually be fairly concerned about a bank who's procedure was to compare new numbers to a complete list of old numbers.

People who don't care enough to learn whether the system is sound or not won't be refusing to use it because it isn't sound. They'll make the decision the same way they make their other decisions, asking: What are successful people doing?

[theymos]

I get that the chance is very, very, very  small. But unless there is no chance at all there is still a chance. All I am saying is that there should be a check to make sure that a new address does not exist already.

There's also a chance your dollars will spontaneously combust... Checking is a waste of time, and if the address already exists when you generate it, then you're the one who gets to steal the previous balance of the address.

[Cryptoman]

I get that the chance is very, very, very  small. But unless there is no chance at all there is still a chance. All I am saying is that there should be a check to make sure that a new address does not exist already.

The chance is probably way less than the chance that a bank's computers and all of their backups will get destroyed and there will be no way of recovering bank deposits.  Has that prevented people from using banks?

[FreeMoney]

Would you trust your money to a bank were the clerk just makes up an account number without checking if the number is already in use?

No but only because humans are really bad at producing truly random numbers.

There are currently 329,993 addresses in the Bitcoin network. Say that this number of addresses are created every day for the next 140 years. That's 16,862,642,300 addresses.

The chance that at least two of those addresses collided is about 9.7x10^-29, using the formula here. Calculation.

I get that the chance is very, very, very  small. But unless there is no chance at all there is still a chance. All I am saying is that there should be a check to make sure that a new address does not exist already.

This is ridiculous. Do you apply the zero chance rule to anything else in your life?

The check is impossible. I don't know if you've used the software, but you can generate addresses offline. Even if this wasn't the case having more people making ever larger numbers of comparisons to protect against one person losing the coins in one address less than one time before the heat death of the universe is crazy.

[SteveB]

Checking is a waste of time, ...

I guess we will have to disagree on that one.

... and if the address already exists when you generate it, then you're the one who gets to steal the previous balance of the address.

I'm more concerned about somebody else generating a new address that already belongs to me and stealing my balance.

[SteveB]

The chance is probably way less than the chance that a bank's computers and all of their backups will get destroyed and there will be no way of recovering bank deposits.  Has that prevented people from using banks?

That is what deposit insurance is for.

[FreeMoney]

The chance is probably way less than the chance that a bank's computers and all of their backups will get destroyed and there will be no way of recovering bank deposits.  Has that prevented people from using banks?

That is what deposit insurance is for.

You think deposit insurance is going to help you if every bank computer and backup is gone?

Buy collision insurance? I'll gladly sell it to you for a one time fee of .1% of insured funds.

[SteveB]

... I don't know if you've used the software, but you can generate addresses offline.

How does generating addresses offline help with collisions? They are still not checked if they are duplicates.

I just don't think that bitcoin has any chance of being taken seriously for big amounts as long as there is even a slight chance of a collision.

[FooDSt4mP]

The check is impossible. I don't know if you've used the software, but you can generate addresses offline. Even if this wasn't the case having more people making ever larger numbers of comparisons to protect against one person losing the coins in one address less than one time before the heat death of the universe is crazy.

What's to stop me from repurposing my miners to continuously generate new addresses?  It doesn't seem like it would take long to generate a significant chunk of the key space.

[theymos]

What's to stop me from repurposing my miners to continuously generate new addresses?  It doesn't seem like it would take long to generate a significant chunk of the key space.

There's no chance that this will ever be profitable.

[caveden]

I get that the chance is very, very, very  small. But unless there is no chance at all there is still a chance.

Don't be ridiculous. It seems you don't really "get that" actually.

There's also a chance that humanity is entirely wiped out by a super meteor falling on earth today. Do you pretend to add "checks" against that, or pass the rest of your life in a meteor-proof bunk?