Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Quantum Studies Mathematics and Foundations

Theoretical derivation of Planck’s constant based on brownian motion model and uncertainty relation

Hideo Nagasaka, Takahiro Mori

Published May 3, 2024• 1 citation
Publisher

Abstract

Abstract In stochastic mechanics, one of the interpretations of realistic quantum mechanics, the Schrödinger equation can be derived by assuming the Brownian motion (BM) of minute particles. In this study, we theoretically derive Planck’s constant (h), a fundamental constant of quantum physics, by assuming same BM. Einstein investigated the BM of a resonator caused by photons in a black body; meanwhile, in this study, BM is considered to be caused by the particle and wave natures of light. As a result, as the functional form of h, $${h}_{N}=\frac{4\pi {e}^{2}}{c{\varepsilon }_{0}}\frac{1}{\beta }$$ h N = 4 π e 2 c ε 0 1 β (e: elementary charge, $${\varepsilon }_{0}$$ ε 0 : permittivity, c: speed of light) was derived, where the undetermined coefficient $$\frac{\beta }{2}$$ β 2 represents the probability that the interaction between electrons and electromagnetic waves becomes particle-like absorption in one cycle of oscillation. The theoretical value of h was calculated to be $$\frac{4\pi {e}^{2}}{c{\varepsilon }_{0}}\pi \sqrt{3}$$ 4 π e 2 c ε 0 π 3 by obtaining β from the transition conditions of the BM model and uncertainty relation. This theoretical value is within 0.3% of the most recent value of h. Besides, Nelson’s assumed diffusion coefficient in the stochastic mechanics, which is essential in obtaining Schrödinger’s equation, was proved to be obtained from the BM model and the uncertainty relation. This finding and the conclusion that the Planck’s constant can be mathematically derived, provide support for Nelson’s stochastic mechanics.

DOI
10.1007/s40509-024-00334-7

Related papers

Can Schroedingerist Wavefunction Physics Explain Brownian Motion? III: A One-Dimensional Heavy and Light Particles Model Exhibiting Brownian-Motion-Like Trajectories and Diffusion

Leonardo De Carlo, W. David Wick

In two prior papers of this series, it was proposed that a wavefunction model of a heavy particle and a collection of light particles might generate ``Brownian-Motion-Like" trajectories as well as diffusive motion (displacement proportional to the square-root of time) of the heavy particle, but did not exhibit a concrete instance. Here we introduce a one-space-dimensional model which, granted a finite perturbation series, fulfills the criteria for BML trajectories and diffusion. We note that Planck's constant and the molecular mass of light particles make an appearance in the diffusion coefficient, which further differentiates the present theory from the work of Poincar{é} and Einstein in the previous century.

arXiv:2412.08764•Dec 11, 2024•0 citations

Quantum Mechanics Derived from the Coulomb Field

Fusao Ishii

Quantum mechanics is defined here as the theoretical framework crystallised at the fifth Solvay Conference of 1927, comprising five postulates: the wavefunction, the canonical commutation relation [x, p] = iℏ, the Born rule, the Schrödinger equation, and the transition probability rule. We present a complete derivation of all five Solvay postulates from purely classical foundations, starting from the directly observable Coulomb field of the electron. The single empirical input is ℏ—measured from pre-Solvay experiments (Planck 1900–1911, Einstein 1905, Casimir 1948/Lamoreaux 1997) without quantum mechanical interpretation, in the same way G was measured by Cavendish (1798) without general relativity. By Einstein’s photoelectric theory (1905) generalized to all electromagnetic fields, the Coulomb field energy is carried in electromagnetic quanta, each carrying both electric and magnetic fields with energy density ϵ0E^2. Lorentz invariance uniquely determines the ZPF spectral energy density u(ω) ∝ ω^3 (Boyer 1969, 1975). The Casimir force measurement gives the total ZPF energy per mode B = ℏ; classical E/B equipartition from Maxwell’s equations gives the electric energy per mode ℏω/2. The central original contribution is the physical justification of the Compton frequency cutoff ωc = mc^2/ℏ: an electron cannot emit an electromagnetic quantum with energy exceeding mc^2, because the residual electron would require negative mass, never observed in nature. By equating two independent expressions for the momentum variance of the ZPF-driven harmonic oscillator—one from the Abraham–Lorentz equation, one from Nelson’s osmotic velocity formula—D = ℏ/2m is derived without any quantum assumption. The ZPF-driven motion is then proved to be Brownian motion in the precise sense of Wiener (1923): all four Wiener conditions are verified from the properties of the ZPF established in Sections 3–4. This answers the question Nelson (1966) explicitly left open: “We do not attempt to give a physical explanation of why the electron should undergo Brownian motion.” The physical explanation is that the electron cannot escape its own Coulomb field. By Itô’s stochastic calculus and Nelson’s theorem, this gives the Schrödinger equation as an effective description valid for timescales Δt ≫ ℏ/mc^2. The transformation ψ = √ρe^(iS/ℏ) linearises the nonlinear Fokker–Planck equation, explaining why superposition holds. All five Solvay postulates emerge as consequences of classical physics plus the single measured constant ℏ. No Solvay postulate is assumed anywhere.

•Jun 16, 2026•0 citations

Quantum-Mechanical Description of a Brownian Particle

L. de la Peña-Auerbach, Ernest Braun, L. S. García Colín

It is shown that the motion of a Brownian particle in the Smoluchowski approximation may be described by a Schrödinger-like equation defining a complex probability amplitude whose norm is the same as the stochastic probability density. Furthermore, the quantum dynamical operators have a physical meaning which arises in a natural way, from the stochastic nature of the process. These operators satisfy the usual commutation relations and thus the uncertainty principle. Here the constant ℏ is replaced by a parameter depending on the characteristics of the system. In particular, the potential-energy operator for a Brownian particle subject to no external forces can be interpreted as a Rayleigh dissipative function.

Journal of Mathematical Physics•May 1, 1968•12 citations

Physical interpretation of Planck’s constant based on the Maxwell theory

Donald C. Chang

The discovery of the Planck relation is generally regarded as the starting point of quantum physics. Planck’s constant h is now regarded as one of the most important universal constants. The physical nature of h , however, has not been well understood. It was originally suggested as a fitting constant to explain the black-body radiation. Although Planck had proposed a theoretical justification of h , he was never satisfied with that. To solve this outstanding problem, we use the Maxwell theory to directly calculate the energy and momentum of a radiation wave packet. We find that the energy of the wave packet is indeed proportional to its oscillation frequency. This allows us to derive the value of Planck’s constant. Furthermore, we show that the emission and transmission of a photon follows the all-or-none principle. The “strength” of the wave packet can be characterized by ζ , which represents the integrated strength of the vector potential along a transverse axis. We reason that ζ should have a fixed cut-off value for all photons. Our results suggest that a wave packet can behave like a particle. This offers a simple explanation to the recent satellite observations that the cosmic microwave background follows closely the black-body radiation as predicted by Planck’s law.

arXiv:1706.04475•Chinese Physics B•Apr 1, 2017•21 citations

Derivation of the Schrödinger Equation from Newtonian Mechanics

EDWARD B. NELSON

We examine the hypothesis that every particle of mass $m$ is subject to a Brownian motion with diffusion coefficient $\frac{\ensuremath{\hbar}}{2m}$ and no friction. The influence of an external field is expressed by means of Newton's law $\mathbf{F}=m\mathbf{a}$, as in the Ornstein-Uhlenbeck theory of macroscopic Brownian motion with friction. The hypothesis leads in a natural way to the Schr\"odinger equation, but the physical interpretation is entirely classical. Particles have continuous trajectories and the wave function is not a complete description of the state. Despite this opposition to quantum mechanics, an examination of the measurement process suggests that, within a limited framework, the two theories are equivalent.

Physical Review•Oct 28, 1966•1,717 citations

A new look at the derivation of the Schrödinger equation from Newtonian mechanics

L. Fritsche, M. Haugk

We present a modified version of Nelson's seminal paper on the derivation of the time-dependent Schrödinger equation which draws on the equation of motion of a particle that moves under the influence of a classical force field and additional stochastic forces. The emphasis of our elaboration is focused on the implication of allowing stochastic forces to occur, viz. that the energy E of the particle is no longer conserved on its trajectory in a conservative force field. We correlate this departure Δ E from its classical energy with the energy/time uncertainty relation where Δ t is the average time for Δ E to persist. The stability of atoms, the zero-point energy of oscillators, the tunneling effect and the diffraction at slits are shown to be directly connected with the occurrence of such energy fluctuations. We discuss and rederive Nelson's theory entirely from this point of view and generalize his approach to systems of N particles which interact via pair forces. Achieving reversibility in a description of particle motion that is akin to Brownian motion, represents a salient point of the derivation. We demonstrate that certain objections raised against Nelson's theory are without substance. We also try to put the particular worldview of this version of stochastic quantum mechanics into perspective with regard to the established Copenhagen interpretation.

Annalen der Physik•Jul 9, 2003•34 citations
Abstract In stochastic mechanics, one of the interpretations of realistic quantum mechanics, the Schrödinger equation can be derived by assuming the Brownian motion (BM) of minute particles. In this study, we theoretically derive Planck’s constant (h), a fundamental constant of quantum physics, by assuming same BM. Einstein investigated the BM of a resonator caused by photons in a black body; meanwhile, in this study, BM is considered to be caused by the particle and wave natures of light. As a result, as the functional form of h, hN=4πe2cε01β{h}_{N}=\frac{4\pi {e}^{2}}{c{\varepsilon }_{0}}\frac{1}{\beta }hN​=cε0​4πe2​β1​ h N = 4 π e 2 c ε 0 1 β (e: elementary charge, ε0{\varepsilon }_{0}ε0​ ε 0 : permittivity, c: speed of light) was derived, where the undetermined coefficient β2\frac{\beta }{2}2β​ β 2 represents the probability that the interaction between electrons and electromagnetic waves becomes particle-like absorption in one cycle of oscillation. The theoretical value of h was calculated to be 4πe2cε0π3\frac{4\pi {e}^{2}}{c{\varepsilon }_{0}}\pi \sqrt{3}cε0​4πe2​π3​ 4 π e 2 c ε 0 π 3 by obtaining β from the transition conditions of the BM model and uncertainty relation. This theoretical value is within 0.3% of the most recent value of h. Besides, Nelson’s assumed diffusion coefficient in the stochastic mechanics, which is essential in obtaining Schrödinger’s equation, was proved to be obtained from the BM model and the uncertainty relation. This finding and the conclusion that the Planck’s constant can be mathematically derived, provide support for Nelson’s stochastic mechanics.
In two prior papers of this series, it was proposed that a wavefunction model of a heavy particle and a collection of light particles might generate ``Brownian-Motion-Like" trajectories as well as diffusive motion (displacement proportional to the square-root of time) of the heavy particle, but did not exhibit a concrete instance. Here we introduce a one-space-dimensional model which, granted a finite perturbation series, fulfills the criteria for BML trajectories and diffusion. We note that Planck's constant and the molecular mass of light particles make an appearance in the diffusion coefficient, which further differentiates the present theory from the work of Poincar{é} and Einstein in the previous century.
Quantum mechanics is defined here as the theoretical framework crystallised at the fifth Solvay Conference of 1927, comprising five postulates: the wavefunction, the canonical commutation relation [x, p] = iℏ, the Born rule, the Schrödinger equation, and the transition probability rule. We present a complete derivation of all five Solvay postulates from purely classical foundations, starting from the directly observable Coulomb field of the electron. The single empirical input is ℏ—measured from pre-Solvay experiments (Planck 1900–1911, Einstein 1905, Casimir 1948/Lamoreaux 1997) without quantum mechanical interpretation, in the same way G was measured by Cavendish (1798) without general relativity. By Einstein’s photoelectric theory (1905) generalized to all electromagnetic fields, the Coulomb field energy is carried in electromagnetic quanta, each carrying both electric and magnetic fields with energy density ϵ0E^2. Lorentz invariance uniquely determines the ZPF spectral energy density u(ω) ∝ ω^3 (Boyer 1969, 1975). The Casimir force measurement gives the total ZPF energy per mode B = ℏ; classical E/B equipartition from Maxwell’s equations gives the electric energy per mode ℏω/2. The central original contribution is the physical justification of the Compton frequency cutoff ωc = mc^2/ℏ: an electron cannot emit an electromagnetic quantum with energy exceeding mc^2, because the residual electron would require negative mass, never observed in nature. By equating two independent expressions for the momentum variance of the ZPF-driven harmonic oscillator—one from the Abraham–Lorentz equation, one from Nelson’s osmotic velocity formula—D = ℏ/2m is derived without any quantum assumption. The ZPF-driven motion is then proved to be Brownian motion in the precise sense of Wiener (1923): all four Wiener conditions are verified from the properties of the ZPF established in Sections 3–4. This answers the question Nelson (1966) explicitly left open: “We do not attempt to give a physical explanation of why the electron should undergo Brownian motion.” The physical explanation is that the electron cannot escape its own Coulomb field. By Itô’s stochastic calculus and Nelson’s theorem, this gives the Schrödinger equation as an effective description valid for timescales Δt ≫ ℏ/mc^2. The transformation ψ = √ρe^(iS/ℏ) linearises the nonlinear Fokker–Planck equation, explaining why superposition holds. All five Solvay postulates emerge as consequences of classical physics plus the single measured constant ℏ. No Solvay postulate is assumed anywhere.
It is shown that the motion of a Brownian particle in the Smoluchowski approximation may be described by a Schrödinger-like equation defining a complex probability amplitude whose norm is the same as the stochastic probability density. Furthermore, the quantum dynamical operators have a physical meaning which arises in a natural way, from the stochastic nature of the process. These operators satisfy the usual commutation relations and thus the uncertainty principle. Here the constant ℏ is replaced by a parameter depending on the characteristics of the system. In particular, the potential-energy operator for a Brownian particle subject to no external forces can be interpreted as a Rayleigh dissipative function.
The discovery of the Planck relation is generally regarded as the starting point of quantum physics. Planck’s constant h is now regarded as one of the most important universal constants. The physical nature of h , however, has not been well understood. It was originally suggested as a fitting constant to explain the black-body radiation. Although Planck had proposed a theoretical justification of h , he was never satisfied with that. To solve this outstanding problem, we use the Maxwell theory to directly calculate the energy and momentum of a radiation wave packet. We find that the energy of the wave packet is indeed proportional to its oscillation frequency. This allows us to derive the value of Planck’s constant. Furthermore, we show that the emission and transmission of a photon follows the all-or-none principle. The “strength” of the wave packet can be characterized by ζ , which represents the integrated strength of the vector potential along a transverse axis. We reason that ζ should have a fixed cut-off value for all photons. Our results suggest that a wave packet can behave like a particle. This offers a simple explanation to the recent satellite observations that the cosmic microwave background follows closely the black-body radiation as predicted by Planck’s law.
We examine the hypothesis that every particle of mass mmm is subject to a Brownian motion with diffusion coefficient $\frac{\ensuremath{\hbar}}{2m}$ and no friction. The influence of an external field is expressed by means of Newton's law F=ma\mathbf{F}=m\mathbf{a}F=ma, as in the Ornstein-Uhlenbeck theory of macroscopic Brownian motion with friction. The hypothesis leads in a natural way to the Schr\"odinger equation, but the physical interpretation is entirely classical. Particles have continuous trajectories and the wave function is not a complete description of the state. Despite this opposition to quantum mechanics, an examination of the measurement process suggests that, within a limited framework, the two theories are equivalent.
We present a modified version of Nelson's seminal paper on the derivation of the time-dependent Schrödinger equation which draws on the equation of motion of a particle that moves under the influence of a classical force field and additional stochastic forces. The emphasis of our elaboration is focused on the implication of allowing stochastic forces to occur, viz. that the energy E of the particle is no longer conserved on its trajectory in a conservative force field. We correlate this departure Δ E from its classical energy with the energy/time uncertainty relation where Δ t is the average time for Δ E to persist. The stability of atoms, the zero-point energy of oscillators, the tunneling effect and the diffraction at slits are shown to be directly connected with the occurrence of such energy fluctuations. We discuss and rederive Nelson's theory entirely from this point of view and generalize his approach to systems of N particles which interact via pair forces. Achieving reversibility in a description of particle motion that is akin to Brownian motion, represents a salient point of the derivation. We demonstrate that certain objections raised against Nelson's theory are without substance. We also try to put the particular worldview of this version of stochastic quantum mechanics into perspective with regard to the established Copenhagen interpretation.