Phys.org July 20, 2018 When physics does not impose any direction on time, where does causal asymmetry—the memory overhead needed to reverse cause and effect—come from? An international team of researchers (Singapore, UC Davis, UK, Austria) has shown that quantum models forced to run in the less-natural temporal direction not only surpass their optimal classical counterparts but also any classical model running in reverse time. This holds even when the memory overhead is unbounded, resulting in quantum models with unbounded memory advantage. According to the researchers the models that use quantum physics can entirely mitigate the memory overhead. Doing away […]