The Impossible Observed

Thomas Breuer

It is shown that it is impossible for an observer to distinguish all present states of a system in which he or she is contained, irrespective of whether this system is a classical or a quantum mechanical one and irrespective of whether the time evolution is deterministic or stochastic. As a corollary, this implies that it is impossible for an observer to measure the EPR-correlations between himself or herself and an outside system. Implications of the main result are discussed for how we have to conceive of universally valid theories.

Vladimir Khomyakov

This paper demonstrates that objective measurement in finite systems is impossible without an explicit observer-relative operator. The observer operator is derived as a structural necessity from finiteness, thermodynamic constraints, and reproducibility principles. The result is independent of interpretational frameworks, numerical simulations, or specific applications.

Himanshu Tyagi, Shun Watanabe

We derive impossibility (converse) bounds for the efficiency of implementing information theoretically secure oblivious transfer and bit commitment using correlated observations. Our approach is based on relating these problems to that of testing if the observations of the parties are conditionally independent given the adversary's observation. The resulting bounds strengthen and improve upon several previously known results.

NAPOLEON CAMUS M. HERMOSO