Question

Which of the following represents the lowest temperature that can be theoretically achieved

Answer 1

where's the question?

Answer 2

The lowest temperature that can theoretically be achieved is referred to as 'Absolute Zero', and is defined as being at 273.15 degrees Celsius or 0 Kelvin. Absolute Zero is the lowest possible temperature where nothing could be colder and no heat energy remains in a substance. It is the point at which particles have minimal vibrational motion (i.e. no real movement of any form), retaining only quantum mechanical, zero-point energy-induced particle motion.

Although it is theoretically possible, I'm not actually sure whether it can ever be physically reached (i.e. we can't get to a point where we remove an infinite amount of heat energy), although scientists have got to temperatures remarkably close to it. This whole area of the behavior of atoms at really low temperatures is actually something which many researchers are trying to explore in greater depth at the moment.