Related Experiment Video
Updated: Feb 2, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
10.4K
Universal dynamics in an isolated one-dimensional Bose gas far from equilibrium
Sebastian Erne1,2,3, Robert Bücker1,4, Thomas Gasenzer2,5
1Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Vienna, Austria.
Nature
|November 9, 2018
Summary
Researchers observed universal scaling in isolated quantum systems far from equilibrium. This finding in a one-dimensional Bose gas provides crucial experimental evidence for universal dynamics in quantum many-body physics.
Area of Science:
- Quantum Many-Body Physics
- Non-Equilibrium Quantum Dynamics
- Ultracold Atomic Gases
Background:
- Understanding quantum systems far from equilibrium is a major challenge.
- Theoretical models predict universal scaling in diverse systems, but experimental evidence is scarce.
- Such universality could link phenomena from the early Universe to heavy-ion collisions and cold atoms.
Purpose of the Study:
- To experimentally demonstrate universal scaling in an isolated quantum system out of equilibrium.
- To characterize the time evolution of a far-from-equilibrium Bose gas.
- To provide a foundation for universality classes in non-equilibrium quantum dynamics.
Main Methods:
- Creation of a one-dimensional Bose gas from a 3D ultracold Bose gas via a strong cooling quench.
- Observation of the time-evolving momentum distribution of the isolated system.
- Analysis of the low-momentum behavior to identify universal scaling functions and exponents.
Main Results:
- Demonstrated universal scaling in the time-evolving momentum distribution of the 1D Bose gas.
- Identified a time-independent universal function and a single scaling exponent governing the low-momentum evolution.
- Observed transport of an emergent conserved quantity towards low momenta, leading to quasi-condensate formation.
Conclusions:
- Established experimental evidence for universal scaling dynamics in an isolated quantum many-body system.
- This work is a critical step towards classifying far-from-equilibrium dynamics by universality.
- Opens possibilities for cold-atom systems to simulate high-energy phenomena like the early Universe.
Related Concept Videos
02:20Dynamic Equilibrium
62.7K
A reversible chemical reaction represents a chemical process that proceeds in both forward (left to right) and reverse (right to left) directions. When the rates of the forward and reverse reactions are equal, the concentrations of the reactant and product species remain constant over time and the system is at equilibrium. A special double arrow is used to emphasize the reversible nature of the reaction. The relative concentrations of reactants and products in equilibrium systems vary greatly;...
62.7K
01:10First Law: Particles in One-dimensional Equilibrium
8.2K
Newton's first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a net external force. It also states that there must be a cause for any change in velocity (a change in either magnitude or direction) to occur. This cause is a net external force. For example, consider what happens to an object sliding along a rough horizontal surface. The object quickly grinds to a halt, due to the net force of friction. If...
8.2K
01:18First Law: Particles in Two-dimensional Equilibrium
16.8K
Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
Newton's first law tells us about...
Newton's first law tells us about...
16.8K
02:46Calculating the Equilibrium Constant
38.0K
The equilibrium constant for a reaction is calculated from the equilibrium concentrations (or pressures) of its reactants and products. If these concentrations are known, the calculation simply involves their substitution into the Kc expression.
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
38.0K
02:56Free Energy and Equilibrium
27.3K
The free energy change for a process may be viewed as a measure of its driving force. A negative value for ΔG represents a driving force for the process in the forward direction, while a positive value represents a driving force for the process in the reverse direction. When ΔGrxn is zero, the forward and reverse driving forces are equal, and the process occurs in both directions at the same rate (the system is at equilibrium).
Recall that Q is the numerical value of the mass action...
Recall that Q is the numerical value of the mass action...
27.3K
01:59Solution Equilibrium and Saturation
21.9K
Imagine adding a small amount of sugar to a glass of water, stirring until all the sugar has dissolved, and then adding a bit more. You can repeat this process until the sugar concentration of the solution reaches its natural limit, a limit determined primarily by the relative strengths of the solute-solute, solute-solvent, and solvent-solvent attractive forces. You can be certain that you have reached this limit because, no matter how long you stir the solution, undissolved sugar remains. The...
21.9K