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Inside physics, absolute zero is a fundamental lower attached on the temperature of a macroscopical body. Around practice these are believed to exist as unrealizable however its being has been inferred from either extrapolation from observed physical phenomena and from kinetic theory. Now these are defined when a temperature at which completely motion of particles would theoretically prevent.

A Kelvin and Rankine temperature scales are defined and then that absolute zero is Cypher kelvins (K) or even Nought degrees Rankine (°R). A Celsius and Fahrenheit scales are defined thus this is −273.Xiv °C or even −459.67 °F.

History
The state of absolute zero was number one proposed by Guillaume Amontons in 1702. Amontons was investigating a relationship between pressure & temperature in gases though he lacked exact and exact thermometers. Though his effects were at better semi-quantitative, he established that a pressure of the flatulency increases by about 1-third between the temperatures of "cold" & a boiling point of h2o. His act led him to speculate that the sufficient reduction within temperature would lead to the disappearance of pressure.

Though absolute zero may be defined therein way, such the definition hwhen practical & conceptual limitations as any real gas will liquefy before attaining a temperature of Nought °R.

Inside 1848, William Thomson, 1st Baron Kelvin proposed an absolute temperature scale within which equal reduction in measured temperature produce to equal reduction in the heat of a immune system. This emancipated a conception from either a constraints of the gas laws and established an absolute zero as the temperature at which there are no farther heat can be transfered from either a system. Absolute zero has never been reached.

Kinetic theory
Based on data from kinetic theory there would exist as there is no movement of single particles at absolute zero, & so any poop at this temperature would be solid. This contradicts experimental grounds to believe. a farther practical definition of absolute zero is when the temperature in which there is no further energy may be extracted. For your needs of loose atoms at temperatures approaching absolute zero, virtually all of a energy is inside the form of translational motion & the temperature may be measured in terms of the distribution of this motion, by having slower speeds corresponding to cold.

In point of fact because of quantum mechanical effects, a speed at absolute zero is non exactly zero, however depends, when does a energy, on the volume inside which the atom is confined. At absolute zero, a molecules and atoms in the models come everthing in the ground state (i.e., a last-place imaginable energy level) & a patterns has a least imaginable total of kinetic energy allowed per laws of physics. This minimal energy corresponds to the zero-point energy encountered in the quantum mechanical particle in a box problem. Equally emphasised above, a moo conceivable energy is non necessarily zero energy, owing to the ramifications of quantum theory.

Cryogenics
It may be shown from either a laws of thermodynamics that absolute zero can never exist as achieved, though these are imaginable to achieve temperatures randomly more or less it through the utilise of cryocoolers. This is the equivalent principle that ensures there is no formulas can be 100% effective.

At super great temperatures in the locality of absolute zero, matter exhibits numbers of unusual properties including superconductivity, superfluidity, and Bose-Einstein condensation. Sequentially to survey such phenomena, man of science use worked to obtain ever frigidity.

As of 2005: The frigidness Bose-Einstein condensation achieved was 450 pK, or Quaternity.Five × 10-10 K. This was performed by Wolfgang Ketterle and colleagues at the Massachusetts Institute of Technology.

The Boomerang Nebula, with the temperature of Single K, is the coldest place known outside the laboratory. A nebula is 5000 light-years from Earth and is in the constellation Centaurus.

The coldest temperature ever produced was C pK when you took an experiment in nuclear magnetic ordering in the Helsinki University of Technology's Low Temperature Lab.

Absolute temperature scales
Absolute or even thermodynamic temperature is conventionally measured in kelvins, and nowadays seldom around degrees Rankine.

An object's absolute temperature so describes how else very much warmer a object is than absolute zero. When temperature occurs as measure of the heat of an object, heat itself is simply the extremely abstract consideration of the kinetic energy of the molecular particles of the object. At absolute zero, i have reached a baseline. A absolute temperature measures a movement among a particles of an object by comparing it to the state of an object at absolute zero.

Negative temperatures

Certain situations may bring about to "negative" temperatures, though this phenomenon is much an artefact of the definition of thermodynamical temperature, like than the models "colder" than absolute zero.

BEC (Bose-Einstein Condensation) Homepage
"A new form of matter at the coldest temperatures in the universe." Simplified, surprisingly clear explanation. Includes cartoon illustrations.

What is absolute zero?
An answer from the Lansing State Journal in Michigan, January 29, 1992.

Steven Chu, former Bell Labs researcher, wins 1997 Nobel in physics
Using lasers to trap and cool molecules for study. Nobel Prize for Chu, Phillips, and Cohen-Tannoudji.

NIST - Atomic Physics Division - Laser Cooling and Trapping Group
This department of the National Institute of Standards and Technology studies the physics of laser cooling, electromagnetic trapping, and other radiative manipulation of neutral atoms and dielectric particles. Home of 1997 Nobel Prize winner William D. Phillips, whose team has cooled atoms to less than a millionth of a degree above absolute zero.

BEC: Bose Einstein Condensation of Sodium
A summary of the NIST project.

Computer Simulation of laser cooling and trapping
Download page for free copies of several "Cool Simulations."

Research groups involved in atom trapping and cooling
A detailed links list of about 50 research groups around the world, with an immense list of subject links, as well. From the Laser Physics Group at Umeå University, Sweden.

Cornell and Wieman Share 2001 Nobel Prize in Physics
Press releases from the National Institute of Standards and Technology and explanations of the work on Bose-Einstein condensates which won the Nobel Prize.

Below Absolute Zero -- What Does Negative Temperature Mean?
Can you really make a system which has a temperature below absolute zero? From the Usenet Physics FAQ.

USC Physics & Astronomy: Physics 151 Lab Manual
Click on: "Experiment X: Ideal Gas Law and the Absolute Zero of Temperature." Requires Adobe Acrobat Reader. The experiment uses liquid nitrogen.






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