The evolution of open quantum systems is a fundamental topic in various scientific fields. During time propagation, the environment occasionally makes measurements, forcing the system’s wave function to collapse randomly. The von Neumann density matrix incorporates the statistics involved in these random processes, and its time development is often described by Markovian quantum master equations that incorporate a dissipator. For large systems, the complexity of the dissipator grows with the increasing number of possible measurements, posing conceptual and severe computational challenges. This article introduces a stochastic representation of the dissipator, using bundled measurement operators to address this complexity. Taking the Morse oscillator as an example, we demonstrate that small samples of bundled operators capture the system’s dynamics. This stochastic bundling is different from the stochastic unraveling and the jump operator formalism and offers a new way of understanding quantum dissipation and decoherence.
Neta Kligler-Vilenchik, Tenenboim-Weinblatt, Keren , Boczkowski, Pablo J. , Hayashi, Kaori , Mitchelstein, Eugenia , ו Villi, Mikko . Submitted.
“Youth Political Talk In The Changing Media Environment: A Cross-National Typology”. The International Journal Of Press/Politics.
תקציר While political communication scholarship has long underscored the importance of political talk—casual conversations about news and politics that occur in everyday situations—as a way for citizens to clarify their opinions and as a precursor for political engagement, much of this literature tends to depict political talk as uncomfortable and difficult for citizens. Yet, this focus on the challenging aspects of political talk has been informed predominantly by the US context. To what extent may a different picture emerge when looking across different cultural contexts? And how are these dynamics shaped by the affordances of the multi-platform social media environment? This paper explores these questions through a unique dataset of 122 qualitative interviews conducted between 2016 and 2019 with young people (ages 18–29) from five countries: Argentina, Finland, Israel, Japan, and the United States. Rather than solidifying the avoidance of controversial political talk as the key strategy at the disposal of young people, our findings point at a five-pronged typology of young people, with each type representing a different approach toward political talk. Our typology thus contributes to a more comprehensive and nuanced picture of various approaches towards political talk employed by young people across different countries and in relation to different digital media affordances.
