arXiv subjects

Andrea Oldofredi

Publications and source records attributed to Andrea Oldofredi.

23 records · Page 2Linked to original sources

arXiv2018

Stochasticity and Bell-type Quantum Field Theory

This paper critically discusses an objection proposed by H. Nikolic against the naturalness of the stochastic dynamics implemented by the Bell-type Quantum Field Theory, an extension of Bohmian Mechanics able to describe the phenomena of particles creation and annihilation. Here I present: (i) Nikolic's ideas for a pilot-wave theory accounting for QFT phenomenology evaluating the robustness of his criticism, (ii) Bell's original proposal for a Bohmian QFT with a particle ontology and (iii) the mentioned Bell-type QFT. I will argue that although Bell's model should be interpreted as a heuristic example showing the possibility to extend Bohm's pilot- wave theory to the domain of QFT, the same judgement does not hold for the Bell-type QFT, which is candidate to be a promising possible alternative proposal to the standard version of quantum field theory. Finally, contra Nikolic, I will provide arguments in order to show how a stochastic dynamics is perfectly compatible with a Bohmian quantum theory.

quant-ph↗

arXiv2017

Particles, Cutoffs and Inequivalent Representations. Fraser andWallace on Quantum Field Theory

We critically review the recent debate between Doreen Fraser and David Wallace on the interpretation of quantum field theory, with the aim of identifying where the core of the disagreement lies. We show that, despite appearances, their conflict does not concern the existence of particles or the occurrence of unitarily inequivalent representations. Instead, the dispute ultimately turns on the very definition of what a quantum field theory is. We further illustrate the fundamental differences between the two approaches by comparing them both to the Bohmian program in quantum field theory.

physics.hist-ph↗

arXiv2016

A persistent particle ontology for QFT in terms of the Dirac sea

We show that the Bohmian approach in terms of persisting particles that move on continuous trajectories following a deterministic law can be literally applied to QFT. By means of the Dirac sea model -- exemplified in the electron sector of the standard model neglecting radiation -- we explain how starting from persisting particles, one is led to standard QFT employing creation and annihilation operators when tracking the dynamics with respect to a reference state, the so-called vacuum. Since on the level of wave functions, both formalisms are mathematically equivalent, this proposal provides for an ontology of QFT that includes a dynamics of individual processes, solves the measurement problem and explains the appearance of creation and annihilation events.

physics.hist-ph↗

arXiv2016

From the universe to subsystems: Why quantum mechanics appears more stochastic than classical mechanics

By means of the examples of classical and Bohmian quantum mechanics, we illustrate the well-known ideas of Boltzmann as to how one gets from laws defined for the universe as a whole to dynamical relations describing the evolution of subsystems. We explain how probabilities enter into this process, what quantum and classical probabilities have in common and where exactly their difference lies.

quant-ph↗

arXiv2015

What is matter? The fundamental ontology of atomism and structural realism

We set out a fundamental ontology of atomism in terms of matter points. While being most parsimonious, this ontology is able to match both classical and quantum mechanics, and it remains a viable option for any future theory of cosmology that goes beyond current quantum physics. The matter points are structurally individuated: all there is to them are the spatial relations in which they stand; neither a commitment to intrinsic properties nor to an absolute space is required. The spatial relations change. All that is needed to capture change is a dynamical structure, namely dynamical relations as expressed in terms of the dynamical parameters of a physical theory.

physics.hist-ph↗