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Dance of the Octopus Electron: What Quantum Tunneling Says About the Nature of Reality

Original: "Field emission tunnelling as a window onto fundamental issues in quantum mechanics"
· Richard G. Forbes
arXiv:2505.00872v4 · 2025-05-01 · CC BY · ⏱ 4 min · Quantum Physics
How electron emission from a tip sheds light on the reality of the wave function, the limits of quantum mechanics, and even the nature of the arrow of time.
Abstract

The article raises fundamental questions of quantum mechanics that are important for field emission (the emission of electrons by a field) and ionization technologies. Among them: whether the electron is a point or a distributed object, how language influences understanding, and why accurate calculation of exchange and correlation effects remains a challenge. These topics touch on fundamentals — from the uncertainty principle to the arrow of time. The authors call for rethinking textbooks: perhaps we've been talking about electrons incorrectly for decades.

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A tiny tungsten tip with a radius of less than a hundred nanometers is the perfect stage for watching a quantum performance. Apply an electric field of a few volts per nanometer, and electrons start flying out of the metal—that’s field emission. It seems like an effect as old as quantum mechanics itself, predicted back in 1928. But beneath the thick layers of established formulas lie unresolved paradoxes. It turns out that during tunneling, the electron doesn’t flick like a point but spreads out in space, like an octopus trying to squeeze through a narrow gap. Its tentacles penetrate the potential barrier while its body still squirms on the other side. Why don’t the electron’s “tail” and “front” get torn apart by the immensely strong electrostatic field? After all, the field pulls them in opposite directions, yet the octopus electron stays intact. This question has haunted theorists for decades.

Two classic approaches to calculating tunnel emission—the tunneling integral method and the overlap integral method—each see the situation differently. The first, rooted in the Schottky–Nordheim barrier, likens tunneling to climbing over a hill: the octopus electron scrambles over the ridge, and the stronger the field, the lower and narrower the pass. The second approach focuses on the overlap of wave functions of the initial and final states—as if the octopus must simultaneously occupy positions in both the metal and the vacuum. Experiments in the field ion microscope deliver harsh assessments. Atoms at the corners of a crystal facet glow brighter—this results from local field enhancement and a shift in the critical surface. The tunneling integral qualitatively reproduces this pattern, while the overlap integral predicts the wrong direction of contrast. As a researcher with half a century of experience noted, neither method accounts for the density of final states in both media, and the fundamental paradox remains: the electron’s front doesn’t detach from its tail even under extreme fields, as if an invisible shell prevents it from disintegrating.

In a field electron microscope, magnifications of around 100,000,000× can be achieved. At room temperature, you can make out chemical bonds in a carbon ring—it’s like examining a cherry the size of Earth and seeing its pit.

The solution, perhaps, lies in abandoning the point-like image of the electron. If we interpret the square of the wave function’s modulus Ψ not as the probability of finding a particle, but as the concentration of “electron substance,” everything falls into place. The equation Ψ(r)Ψ*(r) = n1·ψ(r)ψ*(r), where n1 = 1 electron—a fundamental atomic quantity of matter—tells us directly: the electron is a distributed entity. The octopus wholly fills space, and its “tentacles” are the high-density regions. Then tunneling ceases to be a mystical jump: part of the substance simply seeps through the barrier, like water through a sieve. The transparency coefficient D ≈ exp[–(√(8mₑ/ħ²))∫ M^(1/2)(φ,F,z) dz] quantitatively describes how easily the octopus squeezes through the gap: in the exponent is the integral along the “ridge” of the barrier, where M is the energy difference. The lighter and more energetic the octopus (small mass mₑ, large ħ), the quicker it ends up outside.

This view forces us to revisit the holy of holies—the uncertainty principle. The author proposes replacing the standard constraint on simultaneous measurement of position and momentum with a relation between the minimum kinetic energy and the localization length. This echoes the forgotten ideas of Schrödinger, who initially considered the wave function a real distribution of matter but backed down under criticism. Later, David Bohm and John Stewart Bell sought alternatives to the Copenhagen dogma but never turned to the idea of a distributed electron. Here, however, it emerges from the analysis of field emission. And there’s another bonus: the statistical irreversibility of the tunneling path choice provides a mechanism for the emergence of the arrow of time—a simple alternative to quantum decoherence and the measurement problem.

The brightest atom in a tungsten ion image—the corner atom—shines like a lighthouse because it accumulates a greater positive charge, and the local field more effectively pulls electrons from the gas. The crystal’s geometry turns it into a natural amplifier of quantum signals.

The coming years promise a breakthrough. Advances in ultrafast laser technology promise a real movie of tunneling—frame by frame, we’ll see the octopus seep through the barrier. But the most intriguing part is applying the refined theory to living systems. Tunneling of protons in DNA could explain mutations, and the behavior of helium ions—radiation damage. Carbon nanotubes (carbon) serve as model objects here: images of their chemical bonds, obtained at record magnifications, await direct numerical simulation with the new formalism. If it all works out, we’ll enter the era of quantum biology—where the collapse of the wave function becomes not a philosophical paradox but an engineering tool.

🎯 An image of chemical bonds in a five-membered carbon ring was obtained at room temperature with a magnification of about 100,000,000×. It’s like examining a cherry the size of Earth and seeing its pit!

🎬 This is reminiscent of both the stargate from 2001: A Space Odyssey and the sentient ocean of Solaris—the quantum world never ceases to amaze with its sci-fi nature.

D\approx\exp\left[-\sqrt{\frac{8m_{e}}{\hbar^{2}}}\int_{z_{1}}^{z_{2}}M^{1/2}(\phi,F,z)dz\right]
Barrier transparency coefficient: the lighter the octopus electron and the narrower the mountain pass M, the higher the probability of leakage.
\Psi_{n}(\mathbf{r})\Psi_{n}^{*}(\mathbf{r})=n_{1}\psi(\mathbf{r})\psi^{*}(\mathbf{r})
Density distribution of electron substance; n1 = 1 electron—the fundamental portion of matter, pointing to reality rather than probability.
Scientists
Niels BohrPascual JordanWerner HeisenbergCharles-Augustin de CoulombJames Clerk MaxwellErwin Schrödinger
Tags
wave-particle duality uncertainty principle Wave Function Collapse quantum measurement quantum decoherence electromagnetism hydrogen helium carbon
Laws
Heisenberg uncertainty principleCoulomb's lawPlanck–Einstein relationde Broglie formulaCompton effectRydberg formula
Original: arXiv:2505.00872v4 · CC BY · bridge42worlds