Bitcoin Forum

Let's think big.

Can you think of better interplanetary payment system than just sending bits rather than material representations (which is long and costly)? And most importantly - you do not depend on "the base" since there is no one.

If Mars colonization takes place and grows to self-dependence like states of america did - bitcoin is the only thing that will allow it to turn from colony to independence peacefully (I hope). Thus fertilizing relatively smooth human kind expansion to space.

What you think?

I wonder if block-chain design can handle big latencies and big propagation times. Anyone did such studies or seen it covered?

There was a thread on this a few months ago.

Bitcoin is designed to acheive near realtime concensus between nodes.  In any hypothetical future where interplanetary commerce occurs it is unlikely that the interplanetary commerce is large relative to the intraplanetary commerce.  It is also unlikely that commerce between planets would need to be done in near real-time.   There is no free lunch, to enable consensus where communication latency is measured in minutes not seconds requires some compromises.  The current blockchain wouldn't work or at least it wouldn't work efficiently.   Baring some exotic tech like low cost, high bandwidth FTL communication it is likely that communication between planets will be costly, slow, and have bandwidth limitations not encountered by intraplanetary communication.    

It simply wouldn't make sense to "degrade" the 99%+ of transactions which are intra-planetary in order to fit multiple planets in the same chain.

Likely you would see the emergence of planetary coins (MarsCoins, LunaCoin, etc).   Transfer of wealth between chains could be done via brokers.  A broker could hold reserves in multiple planetary coins and profit via a spread in exchange rates.  If you are on Mars and need to conduct business on earth you could deposit coins at a broker who would exchange them for Bit/Terra coins that you then could use for commerce on Terra.  Companies which deal in interplanetary trade likely would directly accept multiple coins (likely at a higher confirmation requirement) and exchange them with brokers or hold them (and possibly hedge against them).

A more robust system would be a slower interplanetary blockchain (say avg block time of 4 hours) designed to facilitate trade between planetary chains.  It would even be possible to see a single "coin" and multiple chains with a mechanisms in the protocol which allow permanently transferring a coin from one chain to another.  That process would be relatively slow as it would require multiple confirmations in the interplanetary blockchain (at least a day, possibly days).  Under that scenario there never would be more than 21 million bitcoins but the Terra chain for example might only have 14.8 million of them, the rest having been moved to other planetary chains.   It is unlikely end users would interface with such a system but major corporations, trading partners, nations, and banks could settle accounts between chains daily using this chain.

I found out that it takes 10 minutes to send data between Earth and Mars. More infos on interplanetary data transfer (http://deepspace.jpl.nasa.gov/dsn/faq-data.html#q6)

It actually depends on how far Mars is from Earth at the time of transmission.

Seem like I was too optimistic of bitcoin abilities ;)

I think it is more like a "round peg, square hole" scenario.  If you absolutely HAD to use Bitcoin where communication latency was 10+ minutes between nodes it would be possible however it wouldn't be efficient.  Trying to make Bitcoin efficient under such a scenario would also be possible however it would make low latency communication sub-optimal.  Either one "could" be done however there are better options and it is likely those better options would "out compete" bitcoin.

Imagine you are living on Mars and the most common currency is Bitcoin.  Except 99.9% of hashing power and transactions are on Earth, and you will never need 99.9% of those unspent outputs.   While you could start listening to broadcast blocks, and at huge cost in bandwidth synchronize your chain with Earth's chain you would also need to rely on Earth's hashing power.  Having a minority of hashing power and a long latency to the rest of network any blocks you produced would simply be ignored by Earth miners.  Due to the latency you would need to increase the number of confirmations you wait for.

So you could keep using Bitcoin at high cost, and high latency, and forever remain dependent to Earth miners OR you simply start your own chain.  Which do you think will happen?  Which option do you think will be more popular among users, and merchants.  The local chain would be superior (for local commerce) to the far away earth chain.  It would simply be a case of "may the best chain win".

Yes but with merged mining there could be a slow chain alongside all the individual planet's chains, to which all the hashing of all the planets can contribute by all merging it alongside their local chain(s).

Martian BotCoins (MBC) were actually running as a chain some time back but due to lack of sufficient hashing power to secure them they have retreated for the time being to an Open Transactions server, pending sufficient transaction volume for transaction fees to be able to attract enough miners to make the blockchain format secure enough to seem reasonable again. Maybe by that time there will be settlements on Mars so that that eventual move back to blockchain format can happen on Mars.

-MarkM-

When those plucky Martian rovers finally lose the ability to roam about the red planet, can we reprogram them to start off the MarsCoin blockchain ?

And can the Voyager probes hash StarCoin ?

The same issue (in the other direction) occurs just on earth in a future where people are spending BTC from their phones like cash + a potential massive increase in individual transfers due to micropayments (or "milli"-payments).

If the bitcoin protocol evolved into a fractal blockchain, where the larger, slower, blockchains do not verify every transaction of the smaller, faster ones it will solve both interplanetary (extremely slow) and regional (high frequency) transactions.  Note that on a single planet, "regional" would not have to refer to a physical region -- it could be any social network; in fact "regional" blockchain membership could be created automatically by looking at transaction history of the parent blockchain.

Essentially we'd end up creating blockchains both slower and faster then the current one. 

It would be possible to do this with multiple independent "coin" chains but then you'd have the friction of independent markets that trade these different coins.  Just like we have today with gold -> USD.  This is what "litecoin" is attempting to do.  A "better" solution would be to allow the same bitcoin commodity to transfer into and out of the slower and faster blockchains and have the greater blockchain verify some invariants (such as total quantity) of the lesser blockchain -- but not verify every transaction on it.  An additional advantage is that periodically the leaf (final state) of every account in the lesser blockchain could be "committed" to the greater chain, and then that entire chain (the entire history of transactions within that chain) could be restarted.

If you are confused, imagine a "tree" of blockchains...

This architecture relies on the premise the the network has the "scale" property.  That is the premise of localization of payments (i.e. that the majority of payments happen locally); if the average user paid randomly across the entire network (a "scaleless" network), the largest blockchain would see more traffic then the local ones and there would be little point in a fractal design.  I think that bitCoin is "scaleless" as used today, but will become very scaled if mobile payments take off.

A big problem with shoehorning this into the existing system today is the BTC mining award.  There is no way today's blockchain could recognize coins "mined" on other blockchains... so the lesser and greater chains would have to rely entirely on transaction fees.

By the time we get to colonize the Mars, we should have quantum entanglement effect studied in deep, so all communication, no matter how far will be instantaneous.
Btw, research shows that quantum entanglement is part of photosynthesis process, and the entanglement 'lives' much longer in organic, living things. This might lead to organic communication devices. I bet everyone is just too lazy to learn telepathy, so yeah, we'll have to use devices.

Actually it looks like the purported "spooky action at a distance" in the quantum realm might well simply arise from a failure to take into account the topology of space. Joy Christian has written quite a bit on that and seems to have a pretty good point.

-MarkM-

sci-fi much?

Perhaps some sort of exchange from separate bitcoin networks? I.E. Earthcoin - Mooncoin - Marscoin.

All I care about is that I can use my BTC to gain the services of the three-breasted mutant prostitutes that will no doubt be present on Mars.

hint:  total recall.

I would assume their would be its own block chain on each planet and communications between planets would be done within an organization that has set up a their own communication lines to change balances your trust would be in the organization hands by that point though

Separate blockchains or coins is the obvious solution with exchanges. Might also be p2p exchanges by then so you could issue Marscoin asset back securities redeemable for coins. Then you just sell your shares when you get to mars after the trip :)

Unless I misunderstand this aspect of quantum mechanics, there is a "spooky action-at-a-distance" called entanglement that may one day allow for FTL data something like "sub-space" communications. Perhaps an intergalactic blockchain already exists for those miners equipped with the latest quantum computers with Photon-Net modems.

My understanding of quantum entanglement is there is no known method of using it to transmit information faster than light.

Yes, sorry, I realise now I did not phrase my earlier post in such a way as to make clear that Joy Christian's work not only debunks spooky action at a distance as merely a natural reflection of the topology of space (as a two-sphere not a binary scalar) but also leaves it fully non-spooky as in not violating the speed of light.

(The failure to realise that the correct topology is a two-sphere, whose topology naturally correlates points differently from points of scalar binary values, results in imagining some spooky cause must be causing the effects that simply were not understood due to not taking into account the topology of the domain space.)

-MarkM-