Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

2D NMR: Overview of Homonuclear Correlation Techniques01:16

2D NMR: Overview of Homonuclear Correlation Techniques

450
Homonuclear correlation spectroscopy (COSY) is a powerful technique used in Nuclear Magnetic Resonance (NMR) spectroscopy to study the correlations between nuclei of the same type within a molecule. It provides information about scalar couplings between adjacent nuclei, which helps determine connectivity and structural information. There are several COSY variants, each with its unique strengths and experimental parameters.
COSY90 is the standard two-dimensional (2D) COSY experiment that...
450
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals01:17

Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals

3.0K
Ideally, an unpaired electron shows a single peak in the EPR spectrum due to the transition between the two spin energy states. However, coupling interactions can occur between the spins of the unpaired electron and any neighboring spin-active nuclei. This hyperfine coupling results in hyperfine splitting, where the EPR signal is split into multiplets. The signals split into 2nI + 1 peaks, where n is the number of equivalent nuclei and I is the nuclear spin. These splitting patterns provide...
3.0K
¹H NMR: Interpreting Distorted and Overlapping Signals01:02

¹H NMR: Interpreting Distorted and Overlapping Signals

1.3K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.3K
2D NMR: Homonuclear Correlation Spectroscopy (COSY)01:06

2D NMR: Homonuclear Correlation Spectroscopy (COSY)

1.6K
Homonuclear correlation spectroscopy, or COSY, is a 2-dimensional NMR technique that provides information about coupled protons. Typically, the geminal and vicinal coupling are observed. For example, consider the COSY spectrum of ethyl acetate, where its 1D proton NMR spectrum is plotted along the vertical and horizontal axes with their corresponding chemical shift scale. Three spots on the diagonal corresponding to the three peaks in the 1D proton spectrum are called diagonal peaks. The COSY...
1.6K
Trigonometry of Right Triangles01:29

Trigonometry of Right Triangles

72
In a right triangle, trigonometric functions establish specific ratios that describe the relationship between the lengths of the triangle's sides and its acute angles. These relationships are foundational in understanding the structure of right-angled geometry. The sine function quantifies the proportion of the side opposite a given angle compared to the triangle's hypotenuse. In contrast, the cosine function expresses how the side adjacent to the angle relates to the hypotenuse in terms of...
72
Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule01:10

Interpreting ¹H NMR Signal Splitting: The (n + 1) Rule

2.1K
In the AX proton spin system, proton A can sense the two spin states of a coupled proton X, resulting in a doublet NMR signal with two peaks of equal (1:1) intensity. When proton A is coupled to two equivalent protons (AX2 spin system), the spin states of each X can be aligned with or against the external field, creating three possible scenarios. This results in a 1:2:1  triplet signal, where the central peak corresponds to the chemical shift of A and is twice as large or intense as the...
2.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Schrödinger's Cat Meets Occam's Razor.

Entropy (Basel, Switzerland)·2022
Same author

Gull's Theorem Revisited.

Entropy (Basel, Switzerland)·2022
Same author

Comment on 'Quantum correlations are weaved by the spinors of the Euclidean primitives'.

Royal Society open science·2022
Same author

Correction: Gill, R.D. Does Geometric Algebra Provide a Loophole to Bell's Theorem? <i>Entropy</i> 2020, <i>22</i>, 61.

Entropy (Basel, Switzerland)·2021
Same author

Pearle's Hidden-Variable Model Revisited.

Entropy (Basel, Switzerland)·2020
Same author

Does Geometric Algebra Provide a Loophole to Bell's Theorem?

Entropy (Basel, Switzerland)·2020
Same journal

Research on a Regional Availability Evaluation Model for Road-Area High-Entropy Energy Based on Synergy Factors.

Entropy (Basel, Switzerland)·2026
Same journal

Atmospheric Turbulence Channel Modeling and Performance Analysis of a CO-ZP-OFDM Coherent Optical Communication System for UAV Air-to-Ground Scenarios.

Entropy (Basel, Switzerland)·2026
Same journal

Information Geometry and Asymptotic Theory for SMML Estimators.

Entropy (Basel, Switzerland)·2026
Same journal

Correlation Entropy and Power-Law Kinetics.

Entropy (Basel, Switzerland)·2026
Same journal

Research on the Contagion of Systemic Financial Risk Under the Impact of Climate Risks-From the Perspective of Complex Networks and Machine Learning.

Entropy (Basel, Switzerland)·2026
Same journal

The Statistical-Mechanical Meaning of the Wave Function of Quantum Mechanics.

Entropy (Basel, Switzerland)·2026
See all related articles

Related Experiment Video

Updated: Nov 27, 2025

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
11:19

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels

Published on: July 4, 2016

10.9K

The Triangle Wave Versus the Cosine: How Classical Systems Can Optimally Approximate EPR-B Correlations.

Richard David Gill1

  • 1Mathematical Institute, Leiden University, Niels Bohrweg 1, 2333 CA Leiden, The Netherlands.

Entropy (Basel, Switzerland)
|December 8, 2020
PubMed
Summary
This summary is machine-generated.

Classical physics can reproduce quantum correlations, challenging the notion that quantum mechanics is inherently more extreme. This study introduces classical EPR-B correlations and a "spinning bi-coloured disk" model, demonstrating classical systems can exceed quantum correlations.

Keywords:
Bell’s theoremEPR-B experimentslocal hidden variablessimulation modelssinglet correlationsspinning coloured ball modelspinning coloured disk modeltwisted Malus law

More Related Videos

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
10:34

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow

Published on: April 24, 2014

11.1K
Generation and Coherent Control of Pulsed Quantum Frequency Combs
06:42

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

9.4K

Related Experiment Videos

Last Updated: Nov 27, 2025

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
11:19

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels

Published on: July 4, 2016

10.9K
Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
10:34

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow

Published on: April 24, 2014

11.1K
Generation and Coherent Control of Pulsed Quantum Frequency Combs
06:42

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

9.4K

Area of Science:

  • Quantum mechanics
  • Foundations of physics
  • Classical and quantum correlations

Background:

  • Singlet correlations in composite quantum systems exhibit certainty relations and symmetries.
  • Existing research often focuses on specific experimental settings and continuous rotations.

Purpose of the Study:

  • To investigate classical correlation functions satisfying symmetries and certainty relations.
  • To challenge the idea that quantum correlations are exclusively more extreme than classical physics allows.
  • To introduce a heuristic model for classical EPR-B correlations.

Main Methods:

  • Studied classical correlation functions generated by classical physical systems.
  • Investigated continuous, planar rotations and binary symmetries.
  • Developed a heuristic "spinning bi-coloured disk" model.
  • Employed a search procedure involving random generation of classical models and Monte Carlo simulations.

Main Results:

  • Identified classical EPR-B correlations that satisfy certainty relations and rotational symmetry.
  • Demonstrated that imposing certainty relations and rotational symmetry allows other symmetries to be obtained "for free".
  • Provided a concrete example of a classical correlation exceeding quantum correlations over a range of settings.

Conclusions:

  • The widespread idea that quantum correlations are more extreme than classical physics is inaccurate.
  • Classical physics can reproduce and even exceed certain quantum correlations.
  • Further mathematical investigation is needed for transitions between discrete and continuous cases.