In 1994, Peter Shor invented an algorithm that using Quantum Computers, can break asymmetric cryptography algorithms like RSA, ECDSA. The elliptic curve based cryptosystems that are used to secure Bitcoin, Ethereum and most of the other blockchains are vulnerable to quantum computers. Because of this, user accounts are no longer secure and can result in forged transactions or account take-over. The same applies to validator accounts in proof-of-stake systems. Doge Protocol will support multiple quantum-resistant algorithms like Falcon, Dilithium which are candidates for standardization as of NIST round 3. https://csrc.nist.gov/Projects/post-quantum-cryptography/round-3-submissions

Detailed information on how quantum computers can break current blockchains and how Doge Protocol can secure is given in whitepaper at https://dogeprotocol.org/whitepapers/Doge-Protocol-Blockchain-Quantum-Resistance-Whitepaper.pdf.