Jd. Gibbon, A CONJECTURE REGARDING LOCAL BEHAVIOR OF VORTICITY IN THE 3D INCOMPRESSIBLE NAVIER-STOKES EQUATIONS, Physics letters. A, 203(4), 1995, pp. 181-188
Using the 3d incompressible Navier-Stokes equations, it is conjectured
how the L(2)-norms of the vorticity omega and its derivatives within
a local volume of fluid may be dynamically related to, and finitely co
ntrolled by, multifractal properties of this volume. To achieve this,
the idea of time dependent average ''stretching'' and ''contracting''
exponents, respectively s(1) (t) and s(2)(t), is introduced, where s(1
) + s(2) = 3. When natural length scales related to omega acid its der
ivatives are rapidly decreasing in a time interval, it is conjectured
how a fluid volume may deform into a set of spatial ''dimension'' s =
s(1) - s(2), where s satisfies s < 0 in this interval. A plausibility
argument produces the uniform bound of s(1) < 2.5 and s(2) > 0.5, indi
cating that the final state is a quasi two-dimensional pancake-like ob
ject which possesses a fractal-like structure supported by many length
scales.