Impossibilities
This is a collection of impossibility results for decentralized/permissionless systems. The focus here is on math- or CS-style results.
Trustless cross-chain bridges are impossible: SoK: Communication Across Distributed Ledgers, 25th International Conference on Financial Cryptography and Data Security, 2021
Trustless escrow impossibility: Irrationality, Extortion, or Trusted Third-parties: Why it is Impossible to Buy and Sell Physical Goods Securely on the Blockchain, IEEE International Conference on Blockchain, 2021
You can ony have two of correctness, decentralization & cost efficiency: Blockchain Economics, Princeton University Economics department working paper, 2021
UTXO and account-based system decomposition impossibility: A Unifying Theory of Electronic Money and Payment Systems, TechRxiv, 2022
Scaling impossibility: Asset Transfer Ordering Under A No-Negative-Balance Requirement Is NP-Complete, SSRN, 2024
See also The Consequences Of Scalable Blockchains, blog post, 2022
See also Sharding Is Also NP-Complete, blog post, 2022
Decentralized risk-free yield is impossible: Risk-Free Interest Rates in Decentralized Finance, IEEE Fifth International Conference on Blockchain Computing and Applications, 2023
Capital-efficient decentralized stablecoins are impossible: Computer Science Abstractions to Help Reason About Decentralized Stablecoin Design, IEEE Access, 2023
Decentralized trustless oracle impossibility: An impossibility theorem on truth-telling in fully decentralized systems, BIS working paper, 2023
See also The oracle problem and the future of DeFi, BIS Bulletin, 2023
Trustless protocols cannot guarantee price stability: Can Trustless Protocols Guarantee Price Stability?, SSRN, 2023
Compliance impossibility: Tradeoffs in automated financial regulation of decentralized finance due to limits on mutable turing machines, Scientific Reports, 2025
See also The Compliance-Innovation Trade-off, blog post, 2022
Compliance Impossibility Intuition, blog post, 2025
Other collections
This blog has a slightly different focus and covers some economic-equilibrium-focused papers as well. For example a paper proving that full decentralization is incompatible with a broad class of standard economic assumptions about market participants.
And a limited selection of other economic-equilibrium papers that have come up over the years:
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