Effects of superfluidity including the existence of quantized vortices and the reduction of the moment of inertia are discussed, as well as the consequences of coherence such as the Josephson effect and interference phenomena.
Keeping the gas at sufficiently low density can prevent this from occurring.
For the purpose of answering, I assume this refers to the relatively recent phenomenon of Bose-Einstein Condensation in dilute atomic vapors first produced in in Colorado. See Boltzmann statistics Criterion for Bose-Einstein condensation in a gas of weakly interacting particles Bose-Einstein condensation can be described intuitively in the following way: Nearly years ago, Albert Einstein and Satyendra Nath Bose predicted that quantum mechanics could force a large number of particles to behave in concert as if they were only a single particle.
In particular it has been found that many Understanding the phenomenon of bose einstein condensation networks have universal features like the small world property and a scale-free degree distribution. The other really hot area of BEC research is in looking for ways to use BEC systems for quantum information processing.
BEC research has yielded new atomic and optical physics, such as the atom laser Ketterle demonstrated in Other areas that people are working on actively include ultracold chemistry— sticking atoms from a BEC together to make molecules, or trying to directly condense a gas of molecules— and the study of strongly-interacting systems— there was a paper not long ago about some sort of black hole analogue in a BEC system, and if you crank the interaction strength up, you can apparently get into some interesting many-body physics.
BEC is a purely quantum effect, having to do with the way particles relate to one another. For fermions, the Pauli exclusion principle prevents two particles from occupying the same quantum state; whereas for bosons, quantum statistics in this case, Bose-Einstein statistics dramatically increases the probability of finding several particles in the same quantum state.
The review also assesses the accuracy and limitations of the mean-field approach. As a result, there is a great deal of work in using BEC systems to explore condensed matter physics, essentially making cold atoms look like electrons. There is also a good deal of interest in BEC for possible applications in precision measurement.
Potential applications include more-accurate atomic clocks and enhanced techniques to make electronic chips, or integrated circuits. The thermodynamic limit exhibits a scaling behavior in the relevant length and energy scales. The main hurdle in acquiring proof of the new kind of condensate is that it comes into being extremely quickly.
Background[ edit ] In physicsa Bose—Einstein condensate is a state of matter that occurs in certain gases at very low temperatures. Trento Submitted on 3 Jun v1last revised 12 Oct this version, v2 Abstract: Macroscopic wave function In superconductors and liquid helium, the existence of coherence and of a macroscopic wave function is impressively demonstrated through the Josephson effect.
This is how we can turn distance into time," explains staff scientist Tommi Hakala. This is not the same as cooling everything to absolute zero, where you would also have everything in the lowest energy state— at the temperatures where BEC occurs, if you ignored their quantum character, you would expect the particles in the BEC to be distributed over a bunch of different states, moving with different amounts of energy.
A large class of networks that describe real complex systems like the Internet, the world wide webairport networks or the biological networks of molecular interactions, are described by random networks. If you want to build a quantum computer, you need a way to start with a bunch of qubits that are all in the same state, and a BEC could be a good way to get there, because it consists of a macroscopic number of atoms occupying the same quantum state.
In quantum mechanicsthe energy of a bound particle is limited to a set of discrete values, called energy levels. Nevertheless, a similar type of condensation transition can occur also in off-equilibrium classical systems and in particular, complex networks.
Interference pattern of two expanding condensates, demonstrating the coherence of Bose-Einstein condensates Bose-Einstein Condensation a quantum phenomenon in a system of bosons which consists of the fact that at a temperature below a certain critical value called the degeneration temperaturea portion of the particles is aggregated in a state with zero momentum if the system as a whole is at rest.
For example, in the world wide web each web page has a different content, in social networks different people might have different social skills, in airport networks each airport is connected to cities with unevenly distributed economic activity, etc.
These results have implications for any real situation involving random graphs, including the world wide web, social networks, and financial markets. Despite the dilute nature of the gases, interactions profoundly modify the static as well as the dynamic properties of the system; the predictions of mean-field theory are in excellent agreement with available experimental results.
The concept[ edit ] The result of the efforts of Bose and Einstein is the concept of a Bose gasgoverned by the Bose—Einstein statisticswhich describes the statistical distribution of identical particles with integer spin, now known as bosons such as the photon and helium Typical number densities of atoms between and cm3 imply transition temperatures for Bose-Einstein condensation in the nanokelvin or microkelvin regime.
What are the main practical applications that a Bose-Einstein condensate can have? Basic phenomenon in ideal gas In a simplified picture, particles in a gas may be regarded as quantum-mechanical wavepackets which have a spatial extent on the order of a thermal de Broglie wavelength, given by Eq.paper strives to advance our understanding of how this equation captures the phenomenon of Bose– Einstein condensation through the study of a model equation.
For this model we prove existence and uniqueness theorems for global weak solutions. In some cases a Bose–Einstein condensate will.
Abstract: The phenomenon of Bose-Einstein condensation of dilute gases in traps is reviewed from a theoretical perspective. Mean-field theory provides a framework to understand the main features of the condensation and the role of. The author presents a tutorial review of some ideas that are basic to our current understanding of the phenomenon of Bose-Einstein condensation (BEC) in the dilute atomic alkali gases, with special emphasis on the case of.
Bose-Einstein condensates. created a new kind of atomic matter called a Bose-Einstein condensate (BEC). The phenomenon is not only providing new insights into quantum theory – which underpins our understanding of the Universe at the microscopic level – but also opens the door to a host of applications such as.
The phenomenon of Bose-Einstein condensation is responsible for the superfluidity of helium and for the superconductivity of an electron gas, which involves Bose-condensed electron pairs. However, these phenomena happen at high density, and their understanding requires a detailed treatment of the interactions.
A Bose-Einstein condensate forms when an energy minimum of the lattice is reached. Credit: Aalto University / Tommi Hakala and Antti Paraoanu. Researchers at Aalto University, Finland, have created a Bose-Einstein condensate of light coupled with metal electrons, so-called surface plasmon polaritons.Download