24-Hour Relativistic Bit Commitment.

Area of Science:

• Quantum Cryptography
• Information Security
• Relativistic Physics

Background:

• Bit commitment is a core cryptographic primitive essential for secure transactions.
• Perfect security in bit commitment is unattainable with asynchronous classical or quantum communication.
• Previous relativistic protocols achieved only millisecond-level commitment times.

Purpose of the Study:

• To implement and demonstrate a significantly extended duration for secure bit commitment.
• To explore the feasibility of long-duration cryptographic protocols under relativistic constraints.
• To validate recent theoretical advancements suggesting longer durations are secure.

Main Methods:

• Implementation of a relativistic multiround protocol using timed high-speed optical communication.
• Utilized fast data processing techniques for real-time security verification.
• All agents were located within Geneva, adhering to strict relativistic timing and location constraints.

Main Results:

• Successfully demonstrated a 24-hour secure bit commitment, a duration over six orders of magnitude longer than previously achieved.
• The protocol relies solely on optical communication and rapid data processing.
• The system's design suggests potential for even longer durations (e.g., one year) and greater agent location flexibility.

Conclusions:

• The 24-hour bit commitment implementation proves the viability of long-duration secure cryptographic protocols.
• This work overcomes previous limitations thought to restrict commitment durations.
• The developed solution is practical for applications like digital signatures, secure voting, and auctions.