Other mistake: At the welcome home party, Peter/Luke is at the piano with the female piano teacher. She is helping him remember how to play a song. Problem is, she is playing the keys right in front of her, and he is playing the keys right in front of him (you can tell by their hand placement and where their eyes are looking), but they are both playing in the same octave. His notes should have sounded at least an octave higher. Furthermore, when he starts playing the jazzy sounding tune, the keys we hear are very low and would have been to the left of the teacher. He would have had to reach across her to reach those keys, but instead he is playing the keys right in front of him.
The Majestic (2001)
1 other mistake
Directed by: Frank Darabont
Starring: Jim Carrey, Martin Landau, Hal Holbrook, Bob Balaban, Jeffrey DeMunn, Laurie Holden
Factual error: The film is set in 1951 but Peter and Adele have their first dance to the tune "Stranger On The Shore" which was first released in 1961.
Adele: You remember movies but you don't remember your life?
Trivia: The voice of Luke during the reading of the letter is Matt Damon.
Question: Why didn't Peter retaliate against Bob for punching him and letting the town know what a jerk he is?
Answer: Two possible reasons. 1. Hitting him back and telling everybody about Bob being a complete jerk would make him no better then Bob. 2. Bob actually knew the real Luke and if Peter had hit him, Bob could retaliate by telling everybody the truth.