Are you really a realist?

David K. Holbrook

Raoni Wohnrath Arroyo, Christian DE RONDE

Much has been discussed in the philosophy of science about how we should understand the scientific enterprise. On the one hand, scientific realists believe that empirically adequate theories can be supplemented by interpretations that can mirror reality-as-it-is; on the other hand, anti-realists argue that this is not the case, as long as scientific theories make sufficiently accurate experimental predictions the addition of narratives is irrelevant for the scientific enterprise, and regarding narratives, it is preferable to remain agnostic. In this paper, we argue that realism was never really at stake in this debate.

Alexandru Paler, Daniel Herr, Simon J. Devitt

The reliable resource estimation and benchmarking of quantum algorithms is a critical component of the development cycle of viable quantum applications for quantum computers of all sizes. Determining resource bottlenecks in algorithms, especially when resource intensive error correction protocols are required, is crucial to reduce the cost of implementing viable algorithms on actual quantum hardware.

Meinard Kuhlmann

Benjamin Eva

Topos quantum theory (TQT) is standardly portrayed as a kind of ‘neo-realist’ reformulation of quantum mechanics.1 In this article, I study the extent to which TQT can really be characterized as a realist formulation of the theory, and examine the question of whether the kind of realism that is provided by TQT satisfies the philosophical motivations that are usually associated with the search for a realist reformulation of quantum theory. Specifically, I show that the notion of the quantum state is problematic for those who view TQT as a realist reformulation of quantum theory. 1. Introduction2. Topos Quantum Theory 2.1. Phase space2.2. Hilbert space2.3. Beyond Hilbert space2.4. Defining realism2.5. The spectral presheaf2.6. The logic of topos quantum theory3. Interpreting States in Topos Quantum Theory4. Interpreting Truth Values and Clopen Subobjects in Topos Quantum Theory 4.1. Interpreting the truth values4.2. Interpreting Subcl(Σ̲)5. Neo-realism 5.1. The covariant approach6. Conclusion

L. W. Friedrich