Information Causality without Concatenation

Information causality is a physical principle which states that the amount of randomly accessible data over classical communication channel cannot exceed its capacity, even if sender and receiver have access to source nonlocal correlations. This can be used bound nonlocality quantum mechanics without resorting full formalism, with notable example reproducing Tsirelson's Clauser-Horne-Shimony-Holt inequality. Despite being promising, latter result found little generalization other Bell inequalities because limitations imposed by process concatenation, in several nonsignaling resources are put together produce tighter bounds. In this work, we show concatenation successfully replaced limits on capacity. It allows us rederive and, some cases, significantly improve all previously known results simpler manner apply information unapproachable scenarios.