Related Experiment Video
Updated: Nov 15, 2025
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
9.4K
Mixing indistinguishable systems leads to a quantum Gibbs paradox
Benjamin Yadin1,2, Benjamin Morris3, Gerardo Adesso4
1School of Mathematical Sciences and Centre for the Mathematics and Theoretical Physics of Quantum Non-Equilibrium Systems, University Park, University of Nottingham, Nottingham, UK. benjamin.yadin@physics.ox.ac.uk.
Nature Communications
|March 6, 2021
Summary
Quantum mechanics allows an "ignorant" observer to extract work from mixing indistinguishable gases, challenging classical thermodynamics. This quantum effect reveals new insights into observer knowledge and its thermodynamic implications.
Area of Science:
- Quantum Thermodynamics
- Statistical Mechanics
- Information Theory
Background:
- The Gibbs paradox classically relates entropy change to gas distinguishability.
- An 'ignorant' observer, unable to distinguish gases, traditionally cannot extract work from mixing them.
Purpose of the Study:
- To investigate the Gibbs paradox in the quantum realm.
- To explore the role of observer knowledge in quantum thermodynamic processes.
Main Methods:
- Theoretical analysis of quantum gas mixing.
- Application of quantum statistical mechanics principles.
Main Results:
- An 'ignorant' observer can extract work from mixing quantum gases, even if indistinguishable.
- The quantum case allows work extraction equivalent to fully distinguishable gases in the macroscopic limit.
- Quantum mechanics leads to a revised microstate assignment for systems with limited observer knowledge.
Conclusions:
- Observer knowledge is crucial for understanding thermodynamic processes, especially in quantum systems.
- Quantum effects necessitate modifications to semiclassical statistical mechanics and thermodynamics.
- The study highlights genuinely quantum thermodynamic phenomena beyond classical descriptions.
More Related Videos
Related Concept Videos
01:10Propagation of Uncertainty from Systematic Error
1.1K
The atomic mass of an element varies due to the relative ratio of its isotopes. A sample's relative proportion of oxygen isotopes influences its average atomic mass. For instance, if we were to measure the atomic mass of oxygen from a sample, the mass would be a weighted average of the isotopic masses of oxygen in that sample. Since a single sample is not likely to perfectly reflect the true atomic mass of oxygen for all the molecules of oxygen on Earth, the mass we obtain from this...
1.1K
02:49Second Law of Thermodynamics
25.7K
In the quest to identify a property that may reliably predict the spontaneity of a process, a promising candidate has been identified: entropy. Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, a significant conclusion regarding the relation between this property and spontaneity may be reached. In thermodynamic models, the...
25.7K
00:53Second Law of Thermodynamics
66.3K
The Second Law of Thermodynamics states that entropy, or the amount of disorder in a system, increases each time energy is transferred or transformed. Each energy transfer results in a certain amount of energy that is lost—usually in the form of heat—that increases the disorder of the surroundings. This can also be demonstrated in a classic food web. Herbivores harvest chemical energy from plants and release heat and carbon dioxide into the environment. Carnivores harvest the...
66.3K
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
1.2K
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...
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...
1.2K
02:39Entropy
33.0K
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...
33.0K
01:18Entropy
3.2K
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...
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...
3.2K