Maaneli Derakhshani

Rutgers, The State University of New Jersey | Rutgers · Department of Mathematics

Stochastic mechanics (SM), as proposed by Edward Nelson and others in the 20th century, aims to reconstruct quantum mechanics (QM) from a more fundamental theory of classical point particles interacting with a classical-like ether, where said interaction causes the particles to undergo a diffusion process that conserves their average total energy....

This is a progress report on a preliminary feasibility study of experimental setups for preparing and probing a gravitational cat state [1].

We address a long-standing criticism of the stochastic mechanics approach to quantum theory by one of its pioneers, Edward Nelson: multi-time correlations in stochastic mechanics differ from those in textbook quantum theory. We elaborate upon an answer to this criticism by Blanchard et al. (Phys Rev D 34(12):3732–3738, 1986), who showed that if the...

In this work the spontaneous electromagnetic radiation from atomic systems, induced by dynamical wave-function collapse, is investigated in the x-ray domain. Strong departures are evidenced with respect to the simple cases considered until now in the literature, in which the emission is either perfectly coherent (protons in the same nuclei) or inco...

We construct and study the simplest universal dissipative Lindblad master equation for many-body systems with the purpose of a new dissipative extension of existing nonrelativistic theories of fundamental spontaneous decoherence and spontaneous wave function collapse in nature. It is universal as it is written in terms of second-quantized mass dens...

An assessment of how Roger Penrose's (original) argument, illustrating a clash between the principle of general covariance and the superposition principle in quantum mechanics, holds up in one of the oldest and most well-known conventional approaches to quantum gravity: quantum geometrodynamics. Presentation given for the symposium, Musing about...

Modern physics lays its foundations on the pillars of Quantum Mechanics (QM), which has been proven successful to describe the microscopic world of atoms and particles, leading to the construction of the Standard Model. Despite the big success, the old open questions at its very heart, such as the measurement problem and the wave function collapse,...

Models of dynamical wave function collapse consistently describe the breakdown of the quantum superposition with the growing mass of the system by introducing non-linear and stochastic modifications to the standard Schrödinger dynamics. Among them, Continuous Spontaneous Localization (CSL) was extensively investigated both theoretically and experim...

The experimental search of spontaneous radiation signal in the $\gamma$-Rays range produced strong bounds on the models of dynamical wave function collapse, in particular on the Continuous Spontaneous Localization and on the Di\'{o}si-Penrose. Ongoing and future experiments are moving the investigation to the X-Rays domain, also motivated by the in...

We construct and study the simplest universal dissipative Lindblad master equation for many-body systems with the purpose of a new dissipative extension of existing non-relativistic theories of fundamental spontaneous decoherence and spontaneous wave function collapse in Nature. It is universal as it is written in terms of second-quantized mass den...

Talk for the workshop, "The Hitchhiker's Advanced Guide to Quantum Collapse Models and their impact on science, philosophy, technology and biology", November 2, 2022. https://agenda.infn.it/event/32081/timetable/#all.detailed

We address a long-standing criticism of the stochastic mechanics approach to quantum theory by one of its pioneers, Edward Nelson: multi-time correlations in stochastic mechanics differ from those in textbook quantum theory. We elaborate upon an answer to this criticism by Blan-chard et al. (1986), who showed that if the (derived) wave function in...

In this paper we perform a critical analysis of the Orch OR consciousness theory at the crossroad with the newest experimental results coming from the search for spontaneous radiation predicted by the simplest version of gravity-related dynamical collapse models. We conclude that Orch OR theory, when based on the simplest version of gravity-related...

I use simple examples to illustrate a fundamental inconsistency between the textbook quantum mechanical description of how a gravitational cat state interacting with a macroscopic force probe can be dynamically prepared, and the kind of quantum-gravitational cat state considered by Roger Penrose. I point out that the textbook quantum mechanical des...

After reviewing what is known about the passage from the classical Hamilton-Jacobi formulation of non-relativistic point-particle dynamics to the non-relativistic quantum dynamics of point particles whose motion is guided by a wave function that satisfies Schr\"odinger's or Pauli's equation, we study the analogous question for the Lorentz-covariant...

I illustrate two classical physical contexts (classical Hamilton-Jacobi statistical mechanics, and classical Brownian motion in the large friction limit) in which mathematical structures identical to the "quantum potential" emerge and have straightforward physical interpretations in terms of a statistical description of classical point particles mo...

I introduce the idea of a gravitational cat state in the context of non-relativistic quantum mechanics, and sketch Roger Penrose's quantum-gravity-based argument for there being a clash between the linear superpositions principle and the principle of general covariance. I point out that how the clash can be resolved is tied to how one believe the q...

I give a pedagogical introduction to the de Broglie-Bohm pilot-wave theory of a massless, real, scalar field. The level of the presentation is aimed to be accessible to advanced undergraduates in physics, mathematics, and philosophy of physics.

A pedagogical introduction to relativistic quantum mechanics. The level is aimed at advanced undergraduates in physics, mathematics, and philosophy of physics.

An introduction to Dirac constraint quantization of general relativity in the Hamiltonian picture. The presentation is aimed for graduate students in physics and mathematics. I describe the standard Hamiltonian (or 3+1) formulation of general relativity theory, along with its Dirac quantization that results in the so-called "Wheeler-DeWitt equation...

ABSTRACT: Quantum geometrodynamics (QGD), the version of quantum gravity based on the Wheeler-DeWitt equation, is perhaps the most well-known approach to canonical quantization of general relativity theory. It is known that QGD suffers from three interrelated problems [1, 2, 3]: 1) the Problem of Time, 2) the Quantum Measurement Problem, and 3) the...

A critical evaluation of the so-called "semiclassical approximation" in quantum geometrodynamics. I reveal fundamental problems that make its scope much more limited than is often claimed by proponents of quantum geometrodynamics. Presentation given at Equadiff 2019, Leiden, The Netherlands: https://www.universiteitleiden.nl/equadiff2019 https://...

A broad, conceptual introduction to approaches to quantum gravity. Given for the Philosophy of Cosmology seminar (June 3, 2019) of the Descartes Centre for the History and Philosophy of Science at the University of Utrecht, The Netherlands.

A broad introduction to the Big Bang theory and the theory of Cosmic Inflation, with emphasis on conceptual issues. Given for the Philosophy of Cosmology seminar (May 16, 2019) of the Descartes Centre for the History and Philosophy of Science at the University of Utrecht, The Netherlands.

Talk at the APS March Meeting, Boston, 2019.

I show that Hawking's semiclassical argument for black hole evaporation is inconsistent with the assumption of state-vector collapse. I then argue that the quantum geometrodynamical generalization of Hawking's argument, coupled with the many-worlds approach, doesn't work either. Finally, I point out inconsistencies between Hawking's semiclassical a...

I argue that the stochastic mechanics framework constitutes a viable foundation for quantum mechanics (despite widespread belief to the contrary). I also discuss current work extending stochastic mechanics to semiclassical gravity and non-Markovian dynamics.

Talk given at physics workshop at Dartmouth College, Gravity in the Quantum Regime, June 29, 2018 (invited by Dr. Alexander Smith), and at philosophy of physics workshop at Utrecht University, May 8, 2018 (invited by Prof. Dennis Dieks).

Invited talk for Prof. Claus Kiefer's group at the Institute for Theoretical Physics at the University of Cologne (April 2018). Also given at Gravity in the Quantum Regime workshop at Dartmouth College (July 2018).

Stochastic mechanics (SM), as proposed by Edward Nelson and others in the 20th century, aims to reconstruct quantum mechanics (QM) from a more fundamental theory of classical point particles interacting with a classical-like ether, where said interaction causes the particles to undergo a diffusion process that conserves their average total energy....

Short (10 minute) talk in which I sketch the basic idea of stochastic mechanics, the "Wallstrom criticism" thereof, and the basic idea of my proposed reformulation of stochastic mechanics to answer the Wallstrom criticism. http://meetings.aps.org/Meeting/MAR18/Session/L26.6

An experimental design to prepare and probe a gravitational cat state (hereafter, the grav-cat setup) is described, and its connection to foundational issues in quantum gravity and quantum mechanics are discussed. The grav-cat setup is first described within the standard non-relativistic quantum description of Newtonian gravity. While the standard...

Abstract: A gravitational cat state refers to the gravitational field sourced by a mass density in a quantum superposition of two position states. The first part of the talk will begin with an overview of the "grav-cat" setup proposed by Anastopoulos and Hu in [1], a setup that's based on standard Newtonian quantized gravity. The quantum measuremen...

Continuing the development of the ZSM-Newton/Coulomb approach to semiclassical Newtonian gravity/electrodynamics [1], we formulate a ZSM-Newton/Coulomb version of the large N approximation scheme proposed by Oriols et al. [2]. We show that this new large N scheme makes it possible to self-consistently describe the center-of-mass evolution of a larg...

This is the first in a two-part series in which we extend non-relativistic stochastic mechanics, in the ZSM formulation [1, 2], to semiclassical Newtonian gravity (ZSM-Newton) and semiclassical Newtonian electrodynamics (ZSM-Coulomb), under the assumption that the gravitational and electromagnetic fields are fundamentally classical (i.e., not indep...

Using as a testbed the recently proposed "gravcat" experimental scheme in [1], we compare the properties of gravitational cat states in three descriptions: (1) canonical quantum theory (CQT) combined with the Newtonian limit of GR, (2) objective collapse theories (OCTs) extended to the regime of semiclassical Newtonian gravity, and (3) OCTs extende...

Presentation given at the Fourth International Conference on the Nature and Ontology of Spacetime, organized by the Minkowski Institute and the International Society for the Advanced Study of Spacetime

Seminar talk given for the Utrecht University Foundations of Physics group.

Wallstrom's criticism of existing formulations of stochastic mechanics is that they fail to derive quantum theory because they require an \emph{ad hoc} quantization condition on the postulated velocity potential, \emph{S}, in order to derive single-valued Schr\"odinger wave functions. We propose an answer to this criticism by modifying the Nelson-Y...

Seminar talk for the University of Nebraska - Lincoln AMO physics group.