The glyphs for this episode spell out: HEARTS
The glyph for the S has a small heart in place of the usual small circle.
The apartments where the initial fringe event occurs is called the Rosencrantz Building. Walter shows that the building is a site of anomalous disruption of the laws of physics because he flips a coin and it lands on heads ten times in a row, a statistical improbability. These are references to Tom Stoppard's 1966 play "Rosencrantz and Guildenstern Are Dead," which opens with its two main characters (who are also two minor characters from Shakespeare's Hamlet) betting on coin flips. Against the laws of probability, Rosencrantz bets heads--and wins--ninety-two times.
Stevie Wonder's "For Once In My Life" is playing the background when Olivia and Peter kiss in the pub. This is the same song that Olivia sings to Peter in Brown Betty (2010).
The Observer is seen walking past the couple while they are talking in front of the apartment building.
In Alice Merchant's apartment, next to a framed photograph of Alice with her late husband, there is a vase of white tulips. White tulips are a recurring motif throughout the series, representing forgiveness and hope.