The document proposes using authenticated dynamic dictionaries to improve the efficiency of validating transactions in cryptocurrencies. It describes how storing the balance of each public key (PK) in an authenticated data structure like an AVL+ tree, along with a proof of the sender's balance included in each transaction, allows lightweight validation of transactions and blocks. Batching multiple proofs together can further reduce the proof size for validating multiple transactions, improving efficiency and allowing full validation on low-end hardware. This approach avoids the need to store the full state locally and enables light clients and SPV mining.