CNP talk on 2nd Law
Questions:
- Why are certain systems actually irreversible when basic physics is formally reversible?
- Why is there an Arrow of Time?
- Why is Entropy S never decreasing?
- What is Entropy?
- Boltzmann Statistics S = k log W with W number of microstates
- Statistics is not physics. Statistics is something done by Insurance Companies.
- Classical 2nd Law: TdS = Q > 0
- New 2nd Law: Q = Turbulent Dissipation = Loss > 0
- Turbulent Dissipation: Large scale kinetic energy K transformed to small scale K = Heat Energy E from increasing gradients created by reorganizing convection (instability).
- Irreversible because small scale K cannot be organized to large scale K because of finite precision.
- Competition: Increase Difference vs Decrease Difference.
- dE + W = Q with W = pdV work < 0 in compression
- dK - W = - Q
- Classical: Q=TdS not needed. Q > 0 and dS > 0 same thing.
- Summary: Finite Precision Computation + Instability
- Applications: Joule experiment. Newtonian cosmology. Life: anabolism vs metabolism.
- Reality = formal laws of physics + finite precision computation = Computational Euler Equations.
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