Poetic connections to quantum physics

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        THE LOCKLESS DOOR

        by: Robert Frost (1874-1963)

        It went many years,
        But at last came a knock,
        And I thought of the door
        With no lock to lock.
        
        I blew out the light,
        I tip-toed the floor,
        And raised both hands
        In prayer to the door.
        
        But the knock came again
        My window was wide;
        I climbed on the sill
        And descended outside.
        
        Back over the sill
        I bade a “Come in”
        To whoever the knock
        At the door may have been.
        
        So at a knock
        I emptied my cage
        To hide in the world
        And alter with age.

Sublime description of two eigenstates superimposing on each other (I read it as a metaphor of life/death, of being/non-being, or just two different perspectives...) and the observation paradox of Schrödinger's cat :-P