4 papers · 1 filter
Quantum Coin Tossing
Won Young Hwang, In Gyu Koh, Yeong Deok Han
We show that a secure quantum protocol for coin tossing exist. The existence of quantum coin tossing support the conjecture of D.Mayers [Phys.Rev.Lett. 78, 3414(1997)] that only as…
The quantum cryptography and the unambiguous measurement of quantum nonorthogonal states
Won Young Hwang, In Gyu Koh, Yeong Deok Han
We discuss the unambiguous measurement of quantum nonorthogonal states in connection with the quantum cryptography. We show that checking a ratio of null one to signal is essential…
Quantum Cryptography without Public Announcement of Bases
Won Young Hwang, In Gyu Koh, Yeong Deok Han
This paper provides a simple variation of the basic ideas of the BB84 quantum cryptographic scheme leading to a method of key expansion. A secure random sequence (the bases sequenc…
Running Inflation
Jae-weon Lee, In-guy Koh
A first order inflation model where a gauge coupling constant runs as the universe inflates is investigated. This model can solve the graceful-exit problem within Einstein gravity…