11 papers
Quantum information loss
James Fullwood, Wu-zhong Guo, Boyu Yang
We introduce a measure of information loss for any quantum process that may be modeled by a prepare-evolve-measure scenario: Alice prepares an ensemble of states that gets sent via…
Operational time-reversal symmetry for unital qubit channels
Ouyang Ting, James Fullwood, Zhen Wu
The Bayesian inverse of a quantum channel is a channel in the reverse direction of that yields time-symmetric correlations for sequential…
On Lorentzian symmetries of quantum information
James Fullwood, Vlatko Vedral, Edgar Guzmán-González
A foundational result in relativistic quantum information theory due to Peres, Scudo, and Terno, is that von Neumann entropy is not Lorentz invariant. Motivated by the "It from Qub…
The Born rule as a natural transformation of functors
Boyu Yang, James Fullwood
In this work, we show that the quantum mechanical notions of density operator, positive operator-valued measure (POVM), and the Born rule, are all simultaneously encoded in the cat…
The spatiotemporal Born rule is quasiprobabilistic
James Fullwood, Zhihao Ma, Zhen Wu
Contrary to general relativity, quantum theory treats space and time in fundamentally different ways. In particular, while joint probabilities associated with spacelike separated m…
On small perturbations of coherent information
Zhen Wu, Zhihao Ma, James Fullwood
Quantum capacity quantifies the amount of quantum information that can be transmitted by a quantum channel with an arbitrary small probability of error. Mathematically, the quantum…