 There are two limitations regarding what we can learn about the origins of the universe based on the singularity theorems. First, although these results establish the existence of an initial singularity, they do not provide much guidance regarding its structure. The spacetime structure near a “generic” initial singularity has not yet been fully characterized. Partial results have been established for restricted classes of solutions; for example, numerical simulations and a number of theorems support the BKL conjecture, which holds that isotropic, inhomogeneous models exhibit a complicated form of chaotic, oscillatory behavior. The resulting picture of the approach to the initial singularity contrasts sharply with that in FLRW  models.[34]  It is also possible to have non-scalar singularities (Ellis &amp; King 1974).