Topic: Questions about the Long Term Viability of Bitcoin (Read 1499 times)

This is a valid question. If there is no more incentive to mine, then fewer people will mine, and yes, it could probably be vulnerable to a 51% attack.

But note the if there. As long as transaction fees per block are enough to incentivize miners to keep the blockchain properly protected, then there's nothing to worry about. Which means that either bitcoins need to become much more valuable than they are now, or the amount of transaction fees per block will eventually need to increase, or both need to occur to some degree. Considering we have well over 100 years before the last 0.00000001 BTC is mined, this should be addressed (or rendered moot) long before then.



Even in the face of quantum computing, bitcoins sitting in a cold storage address that has never been used before (and thus has never had its public key revealed) will still be safe.



As long as the person knows the private keys (basically just strings of letters and numbers) of the wallet, then even if the keys had to be chiseled into stone, they should still be able to type the keys into their system, import them into a client and spend the money in them.



The system can be extended to provide more decimal places as needed.

The owner of the ancient wallet would still be able to use their private keys, since extending the precision would not require any change to any keys.



Well, most of us here believe and hope that it is. However, we don't know that it is. It's something a gamble (as are most new things)... but it's a risk with an amazing potential payoff.



I think that's a fine gift. I've done the same for younger relatives, and their "savings accounts" have already grown in value quite a bit. I fully expect them to continue doing so long-term.

But keep in mind, you don't have to just rely on M-discs. Private keys can be stored anywhere that you can store letters and numbers, which means you're not limited to digital media. You could print them onto paper, engrave them in metal, chisel them in stone, or even have them stored on the inside of a solid plastic tschotske you whipped up on a 3D printer. They could be the literal numbers and letters, a QR-Code, or hidden inside of some poem that you wrote that represents the numbers and letters. The possibilities are endless; but of course, you'll want to let them know what the symbols are, and how to access them, and how important it is that they store them safely. It wouldn't be good if the system was so complex that they pull it out after 5 or 10 years, and can't make sense of how to extract the private keys (or worse, can't quite remember what it is.)

It's true that Bitcoin is an experiment, but only in the sense that the American Constitution is an experiment in democracy. It is gaining so much momentum it will be unstoppable. The risk vs rewards is very low and the rewards over time are likely to be great. I've thought about this myself for my children though my affliction is merely age. The question for me isn't how much I should leave them, but when I should allow them access to them. I will probably have them sent at the fourth block halving via my attorney. I believe the value will be quite high by then.

How about wondering about the viability of the other systems?

Anyone to think the Euro will last? That the current deficit is sustainable? What will be the price of gas in 50 years? Hey, bitcoin's not perfect, but nothing is in this world.

Yes Bitcoin isn't probably going anywhere until another virtual currency comes along that takes its place and that may not happen for some time.  Already some of the alt-coins are superior to BTC but bitcoin has first mover advantage and has become the standard and is extremely entrenched.

Of course it is very volatile and could drop to $40 in a month, which would cost you 60% of your capital if you bought now.  But there will always be another currency crisis in the future which should supercharge BTC again.

After all of the coins have been mined, it is anticipated that transaction fees will sufficiently compensate the nodes that are securing the network.


Bitcoins that are not in circulation, and remain assigned to one bitcoin address for a long time, do not pose a problem at all.  They will remain there until someone with a copy of the private key transfers them.  The private key could be handwritten on a piece of paper, printed out as a QR code, or saved electronically on a thumb drive or CD-ROM.  All that matters is that the string of letters and numbers that make up the private key can be retrieved and imported into a bitcoin wallet.  You can think of the private key as the password that is associated with a particular bitcoin address.  This private key will allow the bitcoins assigned to the associated bitcoin address to be unlocked.  The private key does not expire.  However, if the private key is lost, the bitcoins will become unspendable.


You may be interested to know that Hal Finney has also been diagnosed with ALS.  He was on the receiving end of the first Bitcoin transaction:

https://bitcointalksearch.org/topic/bitcoin-and-me-hal-finney-155054


Personally, I think it would be wise to set aside a few bitcoins for your daughters.  The peer-to-peer nature of the Bitcoin network makes it virtually indestructible.  There is no guarantee of course that Bitcoin will still be around, but I think the odds are pretty good that it will stand the test of time.

I would recommend reading more to reach your own conclusions but here are some bits to get your started.

All the Bitcoins won't be mined until ~2140 (the exact date may be sooner due to rising hashing power but not more than 30-40 years sooner).  Miners are compensated with block subsidies and fees.  Since the block subsidy keeps halving every ~4 years fees will be more important long before the last bitcoin is mined.

Quantum Computer capable of implementing Shor's algorithm against 256 bit keys (ECC protecting bitcoin addresses) is far beyond capabilities of current systems (we are talking about tens of thousands of qubits). It also requires the public key to be know.  A Bitcoin address is a hash of the public key, and the actual public key remains unknown until an address is used to send funds.  This is one reason why addresses shouldn't be reused.  While not bulletproof it would provide resistance to attack by QC during a transition to a stronger address type.  Bitcoin could be extended to support post-quantum cryptography.  As for QC being used to mine Bitcoins, generally speaking Shor's algorithm can't be used against hashing functions and symmetric encryption algorithms.  Lastly there is no known QC algorithm to solve the somewhat unique problem of Bitcoin mining.  Grover's algorithm can be used to reverse a single hash however it only produces a modest speed improvement and in mining Bitcoin one isn't looking for a single valid hash but rather a set which consists of quadrillions of valid hashes.  It is not a given that QC will EVER provide a superior/faster/cheaper method of solving blocks.

Old wallets are not a problem.  You wouldn't even need to keep the wallet in any particular form.  The private keys for the address(es) holding the funds is all that is needed.  Bitcoins never expire, and private keys don't go stale.  In may help to think of the Bitcoins not in your wallet but being on every copy of the blockchain spread across tens of thousands of nodes.  Your wallet doesn't contain Bitcoins it contains the keys which allow you (or your heirs) to spend those Bitcoins.  As long as the key remains uncompromised coins can be spent as long as the network exists.  I would recommend generating a set of kepairs offline (there are utilities to accomplish this and then storing the private keys and corresponding addresses on more than medium in more than one location (i.e. a MDIC in a home safe, and paper printout in a safety deposit box).

As for leaving your assets to heirs in the Bitcoin form, although I am an advocate I feel it is unethical to not point out that Bitcoin is an experiment.  This has simply has never been done before and "the test of time" is a long time.  Personally I believe on a long enough timeline (decades) Bitcoins will either be worth many magnitudes than they are today or worth nothing (or almost nothing) at all.  As long as you understand both outcomes are possible and make your plans accordingly I don't see a problem with it.

I have a few questions regarding the longevity of Bitcoin and other cryptocurrencies. My apologies if these seem basic or have been answered elsewhere, as I am still new to the subject.

My first question is what would happen in, say, 40 or 50 years, after the coins have all been mined? Will the network be vulnerable to a 51% attack after there is no more incentive to mine?

Next, what are the expected results of the advent of quantum computing on bitcoins? For instance, I believe that computing hashes should probably become trivial, which means that the distribution of rewarded bitcoins will likely shift to companies and institutions possessing such capabilities, but I'm more concerned and interested in any possible security concerns. For instance, will the hashes for transaction chain blocks be similarly compromised? In a similar note, what about wallets over that time? I expect that most people will be able to keep their clients updated in the circumstance that such a vulnerability becomes critical. But what about a bitcoin wallet that has sat around untouched for fifty years?

A related question is what happens in the case of a wallet that appears suddenly after fifty or a hundred years? And I'm not talking about any discernable effect on the economy. Let's presume that we're talking about a wallet with no more than a few bitcoins that re-enter circulation. Will it still be good, assuming for instance that it was written on, say, an m-disc? Is the network built to handle such ancient currency?

And finally, what if the decimal point is not sufficient in the long term? For example, say that in the far future, strong AI has become a reality, and it is possible to spin off a trillion sentient beings on a whim, each of whom demand payment in Satoshis? Can the system handle future divisions, if the current eight decimal points prove insufficient? And what would happen to that hypothetical wallet in that case, assuming its owner were incapable of keeping her wallet client updated through such a critical juncture?

And before you laugh off these questions as trivial or too far in the future to worry about, please understand that they are important to me. I have been diagnosed with Amyotrophic Lateral Sclerosis, or ALS, more commonly known as Lou Gehrig's Disease. I don't have much time left, as it is a terminal illness, and I am already at the point where my breathing is compromised. Respiratory failure could happen at any time. I am the latest recipient of the charity offered by the Society for Venturism, to have my body cryonically preserved after I've passed, with the hope that technology has eventually evolved to the point of making eventual reanimation a real possibility.

Thus, I am carefully weighing my options. Is Bitcoin stable enough to last the test of time? And lest you think that I'm just trying to find a way to "take it with me" after I'm gone, please understand that I will be leaving behind two precious young girls, currently nine and three, and that this damned disease has not only robbed me of a way to make a livelihood, that my government is doing its best to ensure that my family is left destitute.

I would like, as any good father would, to be able to leave something of substance to my children. As you can imagine, life insurance is completely out of reach to me now. And whatever assets remain after I'm gone, which are modest to begin with, will likely not last too long as my wife becomes a single parent, a young widow.

That's why I'm considering a gift of a couple of bitcoins to each of my daughters for their twenty-first birthdays. Assuming that the promise of the thousand year discs hold true for at least twenty years, I can imagine that it might be a bit more generous gift than the current few hundred dollars it would cost. And also assuming that bitcoins at least hold their value for that long.

Thank you for reading this essay, as it's turned into. And if you would like to help with this bequest, feel free to donate bitcoins to 15LMDcti9AfmPbBAFeoUQxR75w7RgWQzv1.

Thanks and stay strong,
Aaron Winborn