  The three condensate wavefunctions of a spinor BEC on a spherical shell can
map the real space to the order-parameter space that also has a spherical
geometry, giving rise to topological excitations called lump solitons. The
homotopy of the mapping endows the lump solitons with quantized winding numbers
counting the wrapping between the two spaces. We present several lump-soliton
solutions to the nonlinear coupled equations minimizing the energy functional.
The energies of the lump solitons with different winding numbers indicate
coexistence of lumps with different winding numbers and a lack of advantage to
break a higher-winding lump soliton into multiple lower-winding ones. Possible
implications are discussed since the predictions are testable in cold-atom
experiments.
