GL play in SB

[Uncle Ernie]

Fella's,

Regarding the call at the GL with Roth going in for the score. I think we all know the play and this post isn't about whether the call was right/wrong. We weren't there.

Here is my question.

When an official in an NFL game raises a hand is he declaring the ball dead? Is this the same as blowing the whistle?

The replay shows the official coming in with an arm up, then he signals touchdown a little bit later. IF this means the ball is dead, do we have an inadvertant arm?