Yet another entropy paradox...

But I hope, a novel one.

We conventionally affect to be puzzled by the coexistence of microlaws
symmetric under time reversal and the noticably time reversal
asymmetric macrolaws which live with them. But what if the microlaws
were also asymmetric under time reversal -- would that make us feel any
better?

In considering a time reversal of the force law f = q v x B, the
convention is that B be flipped, so that the time reversed law has the
same form. Suppose we don't adopt this convention, so now the law has
lost its time reversal symmetry. Is this proper? We don't have to
argue whether this alternate convention is proper, we can model it!

Consider a plasma of electrons and protons in a parallel magnetic and
gravitational field, and also consider a plasma of positrons and
anti-protons in the same set-up. The charge conjugated version then
obeys the proposed dynamics of the time-reversed system (gravitation
merely defines a distinct vertical).

Well, before we seemed to be bothered that symmetric microlaws led to
assymetric macrolaws, and now we have some asymmetric microlaws, so we
should be all set, right? Well, not quite: the two systems are time
reversed models of each other, yet both stubbornly evolve towards
increasing entropy in lab time.

So besides asking how symmetric microlaws fail to produce a symmetric
macroworld, we also may ask how reversed asymmetric microlaws fail to
produce asymmetric macroscopic results.

.

Relevant Pages

  • Re: Yet another entropy paradox...
    ... > We conventionally affect to be puzzled by the coexistence of microlaws ... > convention is that B be flipped, so that the time reversed law has the ... Suppose we don't adopt this convention, ... > lost its time reversal symmetry. ...
    (sci.physics)
  • Re: Yet another entropy paradox...
    ... >> We conventionally affect to be puzzled by the coexistence of microlaws ... >> convention is that B be flipped, so that the time reversed law has the ... Suppose we don't adopt this convention, ... >> lost its time reversal symmetry. ...
    (sci.physics)
  • Re: Yet another entropy paradox...
    ... > We conventionally affect to be puzzled by the coexistence of microlaws ... > convention is that B be flipped, so that the time reversed law has the ... Suppose we don't adopt this convention, ... > lost its time reversal symmetry. ...
    (sci.physics)