Weekly Papers on Quantum Foundations (14)

Authors: T.N.Palmer

Hardy’s axiomatic approach to the quantum theory of discrete Hilbert Spaces reveals that just one principle distinguishes it from classical probability theory: there should be continuous (and hence infinitesimal) reversible transformations between any pair of pure states – the single word `continuous’ giving rise to quantum theory. This raises the question: Can one formulate a finite theory of qubit physics (FTQP) – necessary different from quantum theory – which can replicate the tested predictions of quantum theory of qubits to experimental accuracy? Here we show that an FTQP based on complex Hilbert vectors with rational squared amplitudes and rational phase angles is possible, provided the metric of state space, $g_p$, is based on $p$-adic rather than Euclidean distance. A key number theorem describing an incompatibility between rational angles and rational cosines accounts for quantum complementarity in this FTQP. Dynamical evolution is described by a deterministic mapping on the set of $p$-adic integers and the measurement problem is trivially solved in terms of a nonlinear clustering of states in state space. Based on $g_p$, causal deterministic analyses of quantum interferometry, GHZ, the sequential Stern-Gerlach experiment, Leggett-Garg and the Bell Theorem are described. The close relationship between fractals and $p$-adic integers suggest the existence of a primal fractal-like ‘invariant set’ geometry $I_U$ in cosmological state space, from which space-time and the laws of physics in space-time are emergent.

Authors: Shiva Meucci

The need for revolution in modern physics is a well known and often broached subject, however, the precision and success of current models narrows the possible changes to such a great degree that there appears to be no major change possible. We provide herein, the first step toward a possible solution to this paradox via reinterpretation of the conceptual-theoretical framework while still preserving the modern art and tools in an unaltered form. This redivision of concepts and redistribution of the data can revolutionize expectations of new experimental outcomes. This major change within finely tuned constraints is made possible by the fact that numerous mathematically equivalent theories were direct precursors to, and contemporaneous with, the modern interpretations. In this first of a series of papers, historical investigation of the conceptual lineage of modern theory reveals points of exacting overlap in physical theories which, while now considered cross discipline, originally split from a common source and can be reintegrated as a singular science again. This revival of an older associative hierarchy, combined with modern insights, can open new avenues for investigation. This reintegration of cross-disciplinary theories and tools is defined as the Neoclassical Interpretation.

Wuthrich, Christian (2018) The emergence of space and time. [Preprint]
We thought only fools messed with the cast-iron laws of thermodynamics – but quantum trickery is rewriting the rulebook, says physicist Vlatko Vedral

Abstract

We review connections between the metric of spacetime and the quantum fluctuations of fields. We start with the finding that the spacetime metric can be expressed entirely in terms of the 2-point correlator of the fluctuations of quantum fields. We then discuss the open question whether the knowledge of only the spectra of the quantum fluctuations of fields also suffices to determine the spacetime metric. This question is of interest because spectra are geometric invariants and their quantization would, therefore, have the benefit of not requiring the modding out of diffeomorphisms. Further, we discuss the fact that spacetime at the Planck scale need not necessarily be either discrete or continuous. Instead, results from information theory show that spacetime may be simultaneously discrete and continuous in the same way that information can. Finally, we review the recent finding that a covariant natural ultraviolet cutoff at the Planck scale implies a signature in the cosmic microwave background (CMB) that may become observable.

Abstract

The Horizon Quantum Mechanics is an approach that allows one to analyse the gravitational radius of spherically symmetric systems and compute the probability that a given quantum state is a black hole. We first review the (global) formalism and show how it reproduces a gravitationally inspired GUP relation. This results leads to unacceptably large fluctuations in the horizon size of astrophysical black holes if one insists in describing them as (smeared) central singularities. On the other hand, if they are extended systems, like in the corpuscular models, no such issue arises and one can in fact extend the formalism to include asymptotic mass and angular momentum with the harmonic model of rotating corpuscular black holes. The Horizon Quantum Mechanics then shows that, in simple configurations, the appearance of the inner horizon is suppressed and extremal (macroscopic) geometries seem disfavoured.

Pitts, J. Brian (2017) Underconsideration in Space-time and Particle Physics. [Preprint]

From meat to mind: the root of consciousness

From meat to mind: the root of consciousness, Published online: 04 April 2018; doi:10.1038/d41586-018-03920-z

Douwe Draaisma enjoys Michael Gazzaniga’s exploration of the biological basis of consciousness.

Abstract

I show why old and new claims on the role of counterfactual reasoning for the EPR argument and Bell’s theorem are unjustified: once the logical relation between locality and counterfactual reasoning is clarified, the use of the latter does no harm and the nonlocality result can well follow from the EPR premises. To show why, after emphasizing the role of incompleteness arguments that Einstein developed before the EPR paper, I critically review more recent claims that equate the use of counterfactual reasoning with the assumption of a strong form of realism and argue that such claims are untenable.

Abstract

The hypothesis (Sparenberg et al. in EPJ Web Conf 58:01016, [1]. http://sci-hub.tw/10.1051/epjconf/20135801016) that the particular linear tracks appearing in the measurement of a spherically-emitting radioactive source in a cloud chamber are determined by the (random) positions of atoms or molecules inside the chamber is further explored in the framework of a recently established one-dimensional model (Carlone et al. Comm Comput Phys 18:247, [2]. http://sci-hub.tw/10.4208/cicp.270814.311214a). In this model, meshes of localized spins 1/2 play the role of the cloud-chamber atoms and the spherical wave is replaced by a linear superposition of two wave packets moving from the origin to the left and to the right, evolving deterministically according to the Schrödinger equation. We first revisit these results using a time-dependent approach, where the wave packets impinge on a symmetric two-sided detector. We discuss the evolution of the wave function in the configuration space and stress the interest of a non-symmetric detector in a quantum-measurement perspective. Next we use a time-independent approach to study the scattering of a plane wave on a single-sided detector. Preliminary results are obtained, analytically for the single-spin case and numerically for up to 8 spins. They show that the spin-excitation probabilities are sometimes very sensitive to the parameters of the model, which corroborates the idea that the measurement result could be determined by the atom positions. The possible origin of decoherence and entropy increase in future models is finally discussed.

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