Friday, September 19, 2014

thermodynamics - Does time freeze at Absolute Zero?



Time has many definitions per se, but the basic idea being it's "the measurement of change" so as we know, all matter looses it's ability of changing with the loss of kinetic energy. and the where it becomes zero is the absolute zero (−273.15°C). so my question would be, will time stop/freeze at Absolute zero? and does time get slow while reaching there?



Answer



You are confusing time with the flow of time.


Time is just a coordinate like the spatial coordinates, that is we label spacetime points with four coordinates $(t, x, y, z)$. Indeed, in relativity (both flavours) the time and spatial coordinates get mixed up so different observers will disagree about what is time and what is space.


But the obvious thing about time is that to us humans it appears to flow. We can stand still in space, but we have to keep moving through time at one second per second. I would guess this is what you're thinking of when you say that time is "the measurement of change". The curious thing is that the flow of time doesn't really exist in physics, and some (exactly how many I don't know) physicists believe that the flow of time is a trick of human perception and that time doesn't flow at all. Viewed in this light your question is meaningless, because you are asking about something that doesn't exist.



But even if you take the conventional view of the flow of time, motion does not stop at absolute zero. This is because quantum systems exhibit zero point energy, so their energy remains non-zero even when the temperature is absolute zero. For example helium remains fluid at absolute zero because its zero point energy is too great to allow it to crystallise. So there is no sense in which time stops as we lower the temperature to absolute zero.


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