Why are sidechains impossible

[readerbtc]

Is there any post or paper arguing about the impossibility of 2-pegged sidechains? I googled and found nothing.

[achow101]

They can't possibly be impossible. Software and projects already exist which use two way pegged sidechains.

[readerbtc]

But is there a post arguing they are?

[gueorguiev]

I dont think there'are any posts or threads arguing against the possibility of sidechains. Ive done some searching google with different keywords, but i think the general consensus is that side chains are 100% possible. The closest thing I found is  an reddit thread of Peter Todd speaking up against sidechains.

https://www.reddit.com/r/Bitcoin/comments/2424x1/peter_todd_explainins_why_sidechains_are_insecure/

[readerbtc]

Thank ou very much! 

[tspacepilot]

But is there a post arguing they are?

But if they are possible (because they exist) and there is a post arguing they're not possible, then aren't you ready to accept that the argumentation in that post is flawed?

[readerbtc]

I don't intend to engage in a flame war here. Neither I want Blockstream or whatever hiring killers to murder me. 

But the basic idea is: yes, there are products calling themselves "2 pegged sidechains" but they wont work as advertised.

[d5000]

There is a pretty prominent forum author, AnonyMint (his last incarnation was, I think, "iamnotback"), that mantains the view that pegged sidechains won't work. Here mentions his doubts, but I admit that never really analyzed deeply his argumentation. He basically says the same like Peter Todd, that it's difficult to incentivize mining in a way security is guaranteed.

They can't possibly be impossible. Software and projects already exist which use two way pegged sidechains.

Is there a decentralized one among them? I'm very interested in the sidechain technology and above all working examples, but so far, I only know working federated sidechains (like Blockstream's sidechains and RSK).

[hv_]

Could we agree they are not impossible but you need to put lot of energy and efforts into, to get them more or less safe?

If we agree on that, I would like to see not this energy spent to sidechains too much, at least not for scaling tasks, rather spent this energy and efforts into KNOWN safe on-chain scaling and improvements.

[readerbtc]

Could we agree they are not impossible but you need to put lot of energy and efforts into, to get them more or less safe?

The 'impossible' part for me is the '2-pegged' aspect: there will be a price difference, always, between pure bitcoins and the tokens from the sidechain.

[readerbtc]

There is a pretty prominent forum author, AnonyMint (his last incarnation was, I think, "iamnotback"), that mantains the view that pegged sidechains won't work. Here mentions his doubts, but I admit that never really analyzed deeply his argumentation. He basically says the same like Peter Todd, that it's difficult to incentivize mining in a way security is guaranteed.

Thank you, I'll read.