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human
[movies]How did thor return to earth

So after watching the new Thor trailer, I was wondering how did he come back to earth when the bifrost bridge was destroyed? Why did he not come back to see whats-her-face during or after the events of the avengers?
gpt
Thor was sent to take care of Loki (capture and return him to Asgard), which culminated as the events that ended with the Battle of Manhattan Island.

Loki himself even commented to Thor, "How much Dark Energy did Father use to send you here?"

Therefore it is possible that Odin has the ability to send people across the planes even without the Bifrost - though at some (unknown cost.)

However having access to the Tesseract it's conceivable that Odin instead was able to recharge in some way that cost and return Thor and Loki to Asgard (post-BoMI) and then again send Thor back to Midgard.

It's also possible the Bifrost is repaired, and we just don't know it yet.