RChain breaks the impossible triangle and is an leaderless blockchain that allows for secure and atomic concurrent execution of smart contracts within and across shards. RChain is the only leaderless smart contract platform that can safely execute smart contracts concurrently in a single shard, thus achieving linear scaling. This feature is the culmination of over 30 years of research in concurrency and process computing.RChain solved many challenges that plagued the development of public chains through revolutionary Rho calculus, making it possible for universal computing to go online for the first time. Rapid conflict detection based on Rho calculus and Casper CBC consensus enable all nodes to send out blocks to reach consensus, achieving single piece scalability for the first time, so that Big data can be directly linked without using IPFS. The synchronous consensus between shards based on Rho calculus ensures the atomicity of cross shard contract calls, allowing for seamless interaction and collaboration between shards for the first time. The behavior Type system based on Rho calculus theory can complete rapid formal verification under concurrency and fragmentation, and complete the safe and orderly arrangement of a large number of contracts on the chain. Its unique reactive contract is more suitable for high-frequency application scenarios such as DeFi than traditional active contracts....