Skip to main content



From Wikipedia, the free encyclopedia
Superfluidity is a state of matter in which the matter behaves like a fluid with zero viscosity; where it appears to exhibit the ability to self-propel and travel in a way that defies the forces of gravity and surface tension. While this characteristic was originally discovered in liquid helium, it is also found in astrophysics, high-energy physics, and theories of quantum gravity. The phenomenon is related to Bose–Einstein condensation, but neither is a specific type of the other: not all Bose-Einstein condensates can be regarded as superfluids, and not all superfluids are Bose–Einstein condensates.
Fig. 1. Helium II will "creep" along surfaces in order to find its own level—after a short while, the levels in the two containers will equalize. The Rollin film also covers the interior of the larger container; if it were not sealed, the helium II would creep out and escape.
Fig. 2. The liquid helium is in the superfluid phase. As long as it remains superfluid, it creeps up the wall of the cup as a thin film. It comes down on the outside, forming a drop which will fall into the liquid below. Another drop will form—and so on—until the cup is empty.


Superfluidity of liquid helium

Main article: Superfluid helium-4
In liquid helium, the superfluidity effect was discovered by Pyotr Kapitsa and John F. Allen. It has since been described through phenomenological and microscopic theories. In liquid helium-4, the superfluidity occurs at far higher temperatures than it does in helium-3. Each atom of helium-4 is a boson particle, by virtue of its integer spin. A helium-3 atom is a fermion particle; it can form bosons only by pairing with itself at much lower temperatures. This process is similar to the electron pairing in superconductivity.

Ultracold atomic gases

Superfluidity in an ultracold fermionic gas was experimentally proven by Wolfgang Ketterle and his team who observed quantum vortices in 6Li at a temperature of 50 nK at MIT in April 2005.[1][2] Such vortices had previously been observed in an ultracold bosonic gas using 87Rb in 2000,[3] and more recently in two-dimensional gases.[4] As early as 1999 Lene Hau created such a condensate using sodium atoms[5] for the purpose of slowing light, and later stopping it completely.[6] Her team then subsequently used this system of compressed light[7] to generate the superfluid analogue of shock waves and tornadoes: "These dramatic excitations result in the formation of solitons that in turn decay into quantized vortices—created far out of equilibrium, in pairs of opposite circulation—revealing directly the process of superfluid breakdown in Bose-Einstein condensates. With a double light-roadblock setup, we can generate controlled collisions between shock waves resulting in completely unexpected, nonlinear excitations. We have observed hybrid structures consisting of vortex rings embedded in dark solitonic shells. The vortex rings act as 'phantom propellers' leading to very rich excitation dynamics."[8]

Superfluid in astrophysics

The idea that superfluidity exists inside neutron stars was first proposed by Arkady Migdal.[9][10] By analogy with electrons inside superconductors forming Cooper pairs due to electron-lattice interaction, it is expected that nucleons in a neutron star at sufficiently high density and low temperature can also form Cooper pairs due to the long-range attractive nuclear force and lead to superfluidity and superconductivity.[11]

Superfluidity in high-energy physics and quantum gravity

Superfluid vacuum theory (SVT) is an approach in theoretical physics and quantum mechanics where the physical vacuum is viewed as superfluid.
The ultimate goal of the approach is to develop scientific models that unify quantum mechanics (describing three of the four known fundamental interactions) with gravity. This makes SVT a candidate for the theory of quantum gravity and an extension of the Standard Model. It is hoped that development of such theory would unify into a single consistent model of all fundamental interactions, and to describe all known interactions and elementary particles as different manifestations of the same entity, superfluid vacuum.


Popular posts from this blog

Hidden Wiki

Welcome to The Hidden WikiNew hidden wiki url 2015 http://zqktlwi4fecvo6ri.onion Add it to bookmarks and spread it!!!
Editor's picks Bored? Pick a random page from the article index and replace one of these slots with it.
The Matrix - Very nice to read. How to Exit the Matrix - Learn how to Protect yourself and your rights, online and off. Verifying PGP signatures - A short and simple how-to guide. In Praise Of Hawala - Anonymous informal value transfer system. Volunteer Here are five different things that you can help us out with.
Plunder other hidden service lists for links and place them here! File the SnapBBSIndex links wherever they go. Set external links to HTTPS where available, good certificate, and same content. Care to start recording onionland's history? Check out Onionland's Museum Perform Dead Services Duties. Introduction - Clearnet search engine for Tor Hidden Services (allows you to add new sites to its database). DuckDuckGo - A Hidden S…

Explainer: The nico-teen brain

Explainer: The nico-teen brain The adolescent brain is especially vulnerable to the addictive effects of nicotine BY  TERESA SHIPLEY FELDHAUSEN 7:00AM, AUGUST 19, 2015 Nicotine (black triangle towards center left) tricks the nerve cell (neuron) into sending a message to release more dopamine (yellow dots). Those molecules enter the space (synapse) between one nerve cell and the next. When they get picked up by neighboring cells, this gives users a feel-good high. It also creates the risk of addiction and other health problems.  EMail Print Twitter Facebook Reddit Google+ NATIONAL INSTITUTE ON DRUG ABUSE, ADAPTED BY J. HIRSHFELD Nicotine is the addictive chemical in tobacco smoke and e-cigarette vapors. And doctors say the teenage brain is no place for it to end up. Nicotine can reach the brain within seven seconds of puffing on a cigar, hookah, cigarette or electronic cigarette.
The area of the brain responsible for emotions and controlling our wild impulses is known as the prefrontal c…

fix idm integration on chrome

Chrome Browser IntegrationI do not see IDM extension in Chrome extensions list. How can I install it? 
How to configure IDM extension for Chrome?Please note that all IDM extensions that can be found in Google Store are fake and should not be used. You need to install IDM extension manually from IDM installation folder. Read in step 2 how to do it.

1. Please update IDM to the latest version by using "IDM Help->Check for updates..." menu item

2. I don't see "IDM Integration module" extension in the list of extensions in Chrome. How can I install it?

Press on Chrome menu (arrow 1 on the image), select "Settings" menu item (arrow 2 on the image) and then select "Extensions" tab (arrow 3 on the image). After this open IDM installation folder ("C:\Program Files (x86)\Internet Download Manager" by default, arrow 4 on the image) and drag and drop "IDMGCExt.crx" (arrow 5 on the image) file into "Extensions" page opened in…