[Dave Fangrow (OP)]

Across the range of string theories I'm wondering how the observation of gravity warping space-time is described?  Is it suspected that the graviton string is actually 'attached' or looped through our Calabi-Yau shaped space/time fabric, as opposed to the other force/particle strings that do not stretch space-time?

[Vern]

My understanding is that neither string theory nor Quantum theory explain why gravity warps space-time. Both seem to have abandoned the notion of cause and effect, so they do not entertain "why" type questions.