In theory, absolute zero is the temperature at which the particles of matter (molecules and atoms) are at their lowest energy points. It is a common misconception that at absolute zero particles lose all energy and stop moving. This, however, is false. In quantum physics there is something called zero point energy, which means that even after all the energy that can be extrapolated from particles is extrapolated, particles still have some energy. This is due to the Heisenberg Principle of Uncertainty, which states that the more you know about a particles position, the less you know about it's momentum, and vice versa. Therefore, you cannot have a particle that is stopped, because then you would know both its exact position and momentum. In practice, it is impossible, because, much like reaching the speed of light, the amount of energy required is too vast. Some people have created temperatures very close to absolute zero: the record temperature was 100 pK (one hundred picokelvin, equal to 10-10 kelvin) above absolute zero. Even getting close to absolute zero is difficult because anything that touches an object being cooled near absolute zero would give heat to the objects.

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