Hi Mike Pearson,
I wonder if physicists and physics students are now able to measure heat this way.
Well, there's often a gap between how we understand things and how we deal with them. As far as I can tell, a thermometer is still the best way to measure temperature without changing it much. To measure the motion of each particle would introduce too much disturbance to be useful as a measurement.
Please forgive this 8-year-old messsage from someone else at another forum:
Absolutely. Children can be quite perceptive.
"The increased complexity of the present day biosphere is
: an overall *decrease* in entropy and an *increase* in order, relative
: to the pre-biotic Earth.
I suppose that is correct, because the earth is not a closed system. The sun is constantly making the overall entropy to decrease on earth, which is why we are able to stay alive. Brilliant remark for a child.
The 2nd law doesn't apply to biology. Let's get that through our heads.
: Biological systems are not closed. They are open. The 2nd law simply
: does not have any use here. Biological systems are far from thermodynamic
: equilibrium. That means they are not equilibrium systems. They stay far
: from equilibrium because there is energy flowing through them. The energy
: is dissipated through non-linear interactions within the system, and
: patterns can form spontaneously. Again, forget the 2nd law."
Physics can be tricky sometimes. The only perfectly closed system we are aware of is the universe taken as a whole. Any portion of the universe can experience entropy decrease without violating the 2nd law. And if we find that the universe as a whole is also experiencing entropy decrease, we can always postulate the existence of some meta-universe. Like politics and religious fanatics, scientists can always find an explanation for everything.