I am reading now a book "Erwin Schroedinger and the Quantum revolution" written by John Gribbin and published from Black Swan.
From when I was a student, I have been enchanted by the strange concept of entropy.
We were all taught that the physical system evolves so as to increase its entropy in one direction only.
I have been believing that it is a strict law of nature until today.
But what a surprise to find on page 60 of Gribbin's book!
The Boltzmann himself confessed like this:
"As Boltzmann emphasized in a paper published in the science journal Nature in 1894, the second "law" of thermodynamics is actually only a statement of probability."
Then may we abandon or ignore the inequality dS=dQ/T>0, since it is not an absolute order of nature? The seemingly irreversible process can actually proceed along the reverse direction if we observe it consuming long enough time? In microscopical scale, can each physical process fluctuate among the courses of dS>0 and dS<0?