Talk:Right-hand screw rule

Why not left?

I'll bite: do scientists have any explanation why the direction is not left? --Larry Sanger 12:25, 16 July 2008 (CDT)

The standard answer is: because the Maxwell equations say so. No doubt, the Standard Model, which unifies the electromagnetic forces with nuclear and weak forces, says so too. (I don't know much about the Standard Model, there is a small chance that I could be mistaken). However, this answer is not very satisfactory, because the fixed connection between direction of electric current and magnetic force lines was observed empirically (first by Hans-Christian Oersted), many years before Maxwell wrote down his equations. Of course, when he formulated his theory, Maxwell made sure that his equations "predicted" (were consistent with) the empirical facts that were well-known to him.

I could imagine (although I don't know it for a fact) that the directions are connected through some symmetry, like time-reversal symmetry (running the film backwards). Would that satisfy you as an explanation? Suppose, somebody (a new Einstein) develops a supertheory from which Maxwell's equations and the relation between electric and magnetic directions follow, would that count for you, as a philosopher, as an explanation?

PS. What is important is that the directions are fixed w.r.t. each other, what we humans call right and left is a convention, which could be overthrown one day without changing nature in any way.--Paul Wormer 02:26, 18 July 2008 (CDT)