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

Entropy02:39

Entropy

35.0K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
35.0K
Entropy01:18

Entropy

3.5K
The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
3.5K
Standard Entropy Change for a Reaction03:00

Standard Entropy Change for a Reaction

24.1K
Entropy is a state function, so the standard entropy change for a chemical reaction (ΔS°rxn) can be calculated from the difference in standard entropy between the products and the reactants.
24.1K
Entropy and Solvation02:05

Entropy and Solvation

8.3K
The process of surrounding a solute with solvent is called solvation. It involves evenly distributing the solute within the solvent. The rule of thumb for determining a solvent for a given compound is that like dissolves like. A good solvent has molecular characteristics similar to those of the compound to be dissolved. For example, polar solutions dissolve polar solutes, and apolar solvents dissolve apolar solutes. A polar solvent is a solvent that has a high dielectric constant (ϵ...
8.3K
Entropy within the Cell01:22

Entropy within the Cell

12.7K
A living cell's primary tasks of obtaining, transforming, and using energy to do work may seem simple. However, the second law of thermodynamics explains why these tasks are harder than they appear. None of the energy transfers in the universe are completely efficient. In every energy transfer, some amount of energy is lost in a form that is unusable. In most cases, this form is heat energy. Thermodynamically, heat energy is defined as the energy transferred from one system to another that...
12.7K
Entropy and the Second Law of Thermodynamics01:20

Entropy and the Second Law of Thermodynamics

4.8K
The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
The relation  between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...
4.8K

You might also read

Related Articles

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

Sort by
Same author

Invariance under quantum permutations rules out parastatistics.

Nature communications·2026
Same author

Noise-induced shallow circuits and the absence of barren plateaus.

Nature physics·2026
Same author

Quantum Superpositions of Conscious States in a Minimal Integrated Information Model.

Entropy (Basel, Switzerland)·2026
Same author

Measurement-Driven Quantum Advantages in Shallow Circuits.

Physical review letters·2026
Same author

Uniqueness of Purifications Is Equivalent to Haag Duality.

Physical review letters·2026
Same author

Theory-independent monitoring of the decoherence of a superconducting qubit with generalized contextuality.

Nature communications·2026
Same journal

Erratum: Bacterial Turbulence at Compressible Fluid Interfaces [Phys. Rev. Lett. 136, 138301 (2026)].

Physical review letters·2026
Same journal

Unveiling Light-Quark Yukawa Flavor Structure via Dihadron Fragmentation at Lepton Colliders.

Physical review letters·2026
Same journal

Adaptable Route to Fast Coherent State Transport via Bang-Bang-Bang Protocols.

Physical review letters·2026
Same journal

Topological Transition and Emergence of Elasticity of Dislocation in Skyrmion Lattice: Beyond Kittel's Magnetic-Polar Analogy.

Physical review letters·2026
Same journal

Pound-Drever-Hall Method for Superconducting-Qubit Readout.

Physical review letters·2026
Same journal

Coupling a ^{73}Ge Nuclear Spin to an Electrostatically Defined Quantum Dot in Silicon.

Physical review letters·2026
See all related articles

Related Experiment Video

Updated: Jan 22, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
08:30

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation

Published on: August 14, 2017

11.8K

Von Neumann Entropy from Unitarity.

Paul Boes1, Jens Eisert1, Rodrigo Gallego1

  • 1Dahlem Center for Complex Quantum Systems, Freie Universität Berlin, 14195 Berlin, Germany.

Physical Review Letters
|July 9, 2019
PubMed
Summary
This summary is machine-generated.

We introduce a new way to understand von Neumann entropy, a key quantum information measure. This method characterizes single-shot state transitions without needing many copies or randomness, offering new insights into quantum thermodynamics.

More Related Videos

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
11:15

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy

Published on: June 27, 2013

34.4K
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
09:41

Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides

Published on: May 29, 2018

10.0K

Related Experiment Videos

Last Updated: Jan 22, 2026

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation
08:30

Investigating von Willebrand Factor Pathophysiology Using a Flow Chamber Model of von Willebrand Factor-platelet String Formation

Published on: August 14, 2017

11.8K
Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy
11:15

Applications of EEG Neuroimaging Data: Event-related Potentials, Spectral Power, and Multiscale Entropy

Published on: June 27, 2013

34.4K
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
09:41

Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides

Published on: May 29, 2018

10.0K

Area of Science:

  • Quantum Information Theory
  • Quantum Thermodynamics
  • Quantum Mechanics

Background:

  • The von Neumann entropy quantifies quantum information in asymptotic regimes using many identical and independent (i.i.d.) states.
  • Existing characterizations often rely on i.i.d. limits or explicit randomness, limiting their applicability to single-shot scenarios.

Purpose of the Study:

  • To provide a new operational characterization of von Neumann entropy that does not require i.i.d. limits or randomness.
  • To explore the connection between von Neumann entropy and single-shot state transitions in unitary quantum mechanics.
  • To formulate and provide evidence for the catalytic entropy conjecture.

Main Methods:

  • Demonstrating that von Neumann entropy characterizes single-shot state transitions with a reusable catalyst and a dephasing environment.
  • Formulating the catalytic entropy conjecture, extending this characterization to scenarios without decoherence.
  • Analyzing the implications for operational single-shot interpretations of entropic quantities.

Main Results:

  • A novel operational characterization of von Neumann entropy is established for single-shot state transitions.
  • Evidence is presented for the catalytic entropy conjecture, suggesting a broader applicability of von Neumann entropy in single-shot scenarios.
  • The study challenges the conventional wisdom regarding the necessity of asymptotic limits for entropy characterizations.

Conclusions:

  • The von Neumann entropy plays a crucial role in characterizing single-shot state transitions, even without i.i.d. assumptions or decoherence.
  • The catalytic entropy conjecture, if proven, would establish a profound link between unitary quantum mechanics and entropy.
  • These findings open new avenues for understanding quantum thermodynamics, the third law of quantum thermodynamics, and potentially holography.