[bmalicoat]

Can someone explain why the zero g scenes didn't cascade down through each dream level? They were feeling forces in the first dream in the van and those would go to the hotel but those sleeping there would not feel the same forces (eg lack of gravity) the next level down.

I did really love the idea behind the totem though, very clever.

[forkandwait]

The totem reminded me of passing a reference down a series of recursive calls. Hehe.

[nhnifong]

The root layer reads acceleration from a real sensor (the inner ear) while each successive layer reads acceleration from a virtual sensor provided by the layer above it. That virtual sensor reports the parent layer's acceleration minus a vector taken when the layer was initialized, plus gravity.

[chc]

They didn't talk about it explicitly, but in my mind it was connected to how the guy who got injured felt progressively better each time he went down a dream level. Dreams are affected by what happens above them, but it's sort of passed through a filter.

[Scriptor]

Exactly, the dreamers in the van are feeling 0g, so they're dreaming in 0g as well. However, it's still a dream so when you reach the dream-within-a-dream level, the brain probably defaults to what it's more used to.

[greenlblue]

There are a lot of inconsistencies and you just noticed another one but it's still a really good movie because the inconsistencies are all subtle enough that you are willing to overlook them when you are watching the movie.

[aditya]

Why doesn't the totem work if someone else touches it, though?

[bjg]

The point of the totem is that only you know how it behaves, and how it feels and how it's weight is distributed.

If someone else has held and seen your totem, they can possible recreate it exactly in a dream. If they can recreate it then they can trick you into thinking you aren't dreaming when you actually are.

[AngryParsley]

The totems seem to be pretty vulnerable to trickery, but the film didn't explore that much. For example, (spoiler alert) replace Joseph Gordon-Levitt's loaded die with a fair one. He'll think he's in a dream and kill himself. Making an ever-spinning top would be harder though.