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

System, Surroundings, and State01:24

System, Surroundings, and State

261
Thermodynamics studies the relationship between heat, work, temperature, and energy. A key concept in this field is a "system," the macroscopic part of the universe under observation. Systems can interact with their surroundings, leading to three types: open, closed, and isolated systems.Open systems permit the exchange of both matter and energy with their surroundings, like a boiling pot of water.In contrast, closed systems only allow the transfer of energy, restricting the movement of matter...
261
The Entropy as a State Function01:14

The Entropy as a State Function

125
Consider an arbitrary process that moves between two specific states (A and B) in a cyclic manner. This process is reversible and broken down into smaller parts that each follow a Carnot cycle. A Carnot cycle has two isothermal (constant temperature) processes. During these processes, the ratio of the amount of heat transferred to their respective temperature remains constant. The other two processes in the Carnot cycle are also reversible but adiabatic, which means they occur without any heat...
125
Thermodynamic Systems01:06

Thermodynamic Systems

9.3K
A thermodynamic system is a set of objects whose thermodynamic properties are of interest. The system is considered to be embedded in its surroundings or the environment. The system and its environment can exchange heat and do work on each other through a boundary that separates them. However, the immediate surroundings of the system interact with it directly and therefore have a much stronger influence on its behavior and properties.
Consider an example of  tea boiling in a kettle. The...
9.3K
Thermal Sigmatropic Reactions: Overview01:16

Thermal Sigmatropic Reactions: Overview

2.7K
Sigmatropic rearrangements are a class of pericyclic reactions in which a σ bond migrates from one part of a π system to another. These are intramolecular rearrangements where the total number of σ and π bonds remain unchanged.
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
2.7K
Path Between Thermodynamics States01:21

Path Between Thermodynamics States

5.1K
Consider the two thermodynamic processes involving an ideal gas that are represented by paths AC and ABC in Figure 1:
5.1K
State Space Representation01:27

State Space Representation

754
The frequency-domain technique, commonly used in analyzing and designing feedback control systems, is effective for linear, time-invariant systems. However, it falls short when dealing with nonlinear, time-varying, and multiple-input multiple-output systems. The time-domain or state-space approach addresses these limitations by utilizing state variables to construct simultaneous, first-order differential equations, known as state equations, for an nth-order system.
Consider an RLC circuit, a...
754

You might also read

Related Articles

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

Sort by
Same author

Phase Space Fractons.

Physical review letters·2026
Same author

Intermuscular Xanthoma between the abdominal oblique muscles mimicking soft tissue neoplasia in a dog.

BMC veterinary research·2026
Same author

The moving Born-Oppenheimer approximation.

Proceedings of the National Academy of Sciences of the United States of America·2026
Same author

Symmetry Rebreaking in an Effective Theory of Quantum Coarsening.

Physical review letters·2026
Same author

Reevaluating the Potential of a Vanilla Transformer Encoder for Unsupervised Time Series Anomaly Detection in Sensor Applications.

Sensors (Basel, Switzerland)·2025
Same author

Quantum Turnstiles for Robust Measurement of Full Counting Statistics.

Physical review letters·2025
Same journal

Tension on dsDNA bound to ssDNA-RecA filaments may play an important role in driving efficient and accurate homology recognition and strand exchange.

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Amplitude-phase coupling drives chimera states in globally coupled laser networks [Phys. Rev. E 91, 040901(R) (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Erratum: Shapes of sedimenting soft elastic capsules in a viscous fluid [Phys. Rev. E 92, 033003 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Erratum: Attenuation of excitation decay rate due to collective effect [Phys. Rev. E 90, 022142 (2014)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Role of connectivity and fluctuations in the nucleation of calcium waves in cardiac cells [Phys. Rev. E 92, 052715 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Lattice Boltzmann approach for complex nonequilibrium flows [Phys. Rev. E 92, 043308 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
See all related articles

Related Experiment Video

Updated: Apr 19, 2026

Characterization of Thermal Transport in One-dimensional Solid Materials
05:20

Characterization of Thermal Transport in One-dimensional Solid Materials

Published on: January 26, 2014

19.7K

Eigenstate thermalization and representative states on subsystems.

Vedika Khemani1, Anushya Chandran2, Hyungwon Kim1

  • 1Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2014
PubMed
Summary
This summary is machine-generated.

Researchers show that pure quantum states can describe subsystems, even when entangled. This simplifies quantum mechanics calculations by avoiding reduced density matrices, using representative states derived from the eigenstate thermalization hypothesis (ETH).

More Related Videos

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

9.1K
High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings
09:01

High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings

Published on: April 16, 2017

8.3K

Related Experiment Videos

Last Updated: Apr 19, 2026

Characterization of Thermal Transport in One-dimensional Solid Materials
05:20

Characterization of Thermal Transport in One-dimensional Solid Materials

Published on: January 26, 2014

19.7K
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

9.1K
High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings
09:01

High-resolution Thermal Micro-imaging Using Europium Chelate Luminescent Coatings

Published on: April 16, 2017

8.3K

Area of Science:

  • Quantum Mechanics
  • Quantum Statistical Mechanics

Background:

  • Quantum systems are often described by reduced density matrices when subsystems are entangled.
  • This traditional approach can be computationally intensive.

Purpose of the Study:

  • To investigate if pure states can effectively describe entangled quantum subsystems.
  • To explore alternative methods for calculating expectation values in quantum systems.

Main Methods:

  • Utilizing insights from the eigenstate thermalization hypothesis (ETH).
  • Developing the concept of "representative states" for quantum subsystems.

Main Results:

  • Demonstrating that expectation values of typical operators can be computed using pure states on subsystems.
  • Showing these computations can be done with controlled error.

Conclusions:

  • Pure "representative states" offer a viable alternative to reduced density matrices for describing entangled quantum subsystems.
  • This approach simplifies quantum mechanical calculations and is supported by quantum statistical mechanics principles.