ScienceDirect Publication: Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics
Source:Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics
Author(s): Simon Friederich
The paper has three main aims: first, to make the asymptotic safety-based approach to quantum gravity better known to the community of researchers in the history and philosophy of modern physics by outlining its motivation, core tenets, and achievements so far; second, to preliminarily elucidate the finding that, according to the asymptotic safety scenario, space-time has fractal dimension 2 at short length scales; and, third, to provide the basis for a methodological appraisal of the asymptotic safety-based approach to quantum gravity in the light of the Kuhnian criteria of theory choice.
Quantum teleportation, onwards and upwards
Quantum teleportation, onwards and upwards, Published online: 05 January 2018; doi:10.1038/nphys4339
As we move beyond the twentieth anniversary of the teleportation of a quantum state, it's clear that the coming years will be just as fruitful.
The Logos Categorical Approach to Quantum Mechanics: I. Kochen-Specker Contextuality and Global Intensive Valuations.
In the last 20 years or so, since the publication of a seminal paper by Watts and Strogatz (Nature 393(6684):440–442, 1998), an interest in topological explanations (Huneman in Synthese 177:213–245, 2010) has spread like a wild fire over many areas of science, e.g. ecology, evolutionary biology, medicine, and cognitive neuroscience. The topological approach is still very young by all standards, and even within special sciences it still doesn’t have a single methodological programme that is applicable across all areas of science. That is why this special issue is important as a first systematic philosophical study of topological explanations and their relation to a well understood and widespread explanatory strategy, such as mechanistic one.
We implement the entanglement harvesting protocol, in which two Unruh-DeWitt detectors become entangled through local interactions with a quantum field, for the first time in the vicinity of a black hole. Our study, focusing on the BTZ black hole, reveals that black holes inhibit entanglement harvesting. The entanglement harvested rapidly falls to zero when two detectors with fixed proper separation approach the horizon. This effect is a combination of black hole radiation and gravitational red shift, both generic properties of horizons, suggesting it is a general result for black holes.
Quantum optics and classical optics have coexisted for nearly a century as two distinct, self-consistent descriptions of light. What influences there were between the two domains all tended to go in one direction, as concepts from classical optics were incorporated into quantum theory's early development. But it's becoming increasingly clear that a significant quantum presence exists in classical territory-and, in particular, that the quintessential quantum attribute, entanglement, can be seen, studied and exploited in classical optics. This blurring of the classical-quantum boundary has opened up a potential new direction for frontier work in optics.
Snow Queen is Evil and Beautiful: Experimental Evidence for Probabilistic Contextuality in Human Choices. (arXiv:1711.00418v6 [q-bio.NC] UPDATED)
We present unambiguous experimental evidence for (quantum-like) probabilistic contextuality in psychology. All previous attempts to find contextuality in a psychological experiment were unsuccessful because of the gross violations of marginal selectivity in behavioral data, making the traditional mathematical tests developed in quantum mechanics inapplicable. In our crowdsourcing experiment respondents were making two simple choices: of one of two characters in a story (The Snow Queen by Hans Christian Andersen), and of one of two characteristics, such as Kind and Evil, so that the character and the characteristic chosen matched the story line. The formal structure of the experiment imitated that of the Einstein-Podolsky-Rosen paradigm in the Bohm-Bell version. Marginal selectivity was violated, indicating that the two choices were directly influencing each other, but the application of a mathematical test developed in the Contextuality-by-Default theory, extending the traditional quantum-mechanical test, indicated a strong presence of contextuality proper, not reducible to direct influences.
Uncovering the origin of the arrow of time remains a fundamental scientific challenge. Within the framework of statistical physics, this problem was inextricably associated with the Second Law of Thermodynamics, which declares that entropy growth proceeds from the system's entanglement with the environment. It remains to be seen, however, whether the irreversibility of time is a fundamental law of nature or whether, on the contrary, it might be circumvented. Here we show that, while in nature the complex conjugation needed for time reversal is exponentially improbable, one can design a quantum algorithm that includes complex conjugation and thus reverses a given quantum state. Using this algorithm on an IBM quantum computer enables us to experimentally demonstrate a backward time dynamics for an electron scattered on a two-level impurity.