I didn't get it.
Well actually, I kind of did. It had this message that it's not about how long you live but how you live - enjoy the pleasures of life.
What I didn't get was why the main girl was sleeping with the teacher. I didn't get that. Also, the ending confused me. Did the teacher kill himself?
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Don't be a hater, dear. www.youtube.com/user/dinoatcharterdotnet
I didn't take the hippie crap to be the point. I thought it was a battle for control. On the first two iterations, the teacher was manipulating the variables in the experiment to force the results he wanted. He was trying to use the experiment to convince her that her boyfriend wasn't worthy of her. On the iteration Petra ran, she basically seized control of the rules of the game. He tried to logically box her in by ensuring the only way to preserve the species was to do it his way, so she fought back by changing the goal of the experiment to something else (enjoying the time they had left to live).
She was shirking his control. It paralleled their real life situation where he was hoping to manipulate her into staying with him and her ultimately rejecting that and sticking with her own plan.