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Riemann Zeta Function
Kyono has two Chinese characters tattooed on her left upper arm. The upper one is pronounced "meng" and means "dream". However, the tattoo is upside down. The lower one is pronounced "xiao" and means "laughter."
Ethan says he attended one of Charlie's lectures on the "P vs. NP" problem. This was as a reference to show that Charlie was a well-known professor, as well as delving back to the episode "Uncertainty Principle".
As Charlie discusses the Riemann Hypothesis, and its relation to very large prime numbers, The onscreen graphics depict what he is talking about. One of the large numbers shown has "10" for its final two digits. This cannot be a prime number.
Watch the light outside when Don and Terry are in the basement compared with when they walk out. The sun is setting when they're in the basement, but it's late afternoon when they leave.
The door to the room in which Emily was held was locked from the outside. We know this because the FBI agent had to unlock it. So how did Ballard get in?
How was Atwood trying escape through a window that obviously had bars on it?
Watch closely when Ethan tosses the books. There are three different camera angles in which they film this. All three show him throwing the books at different points in the room.
The kidnappers have the little girl tell her parents to call 818-555-0175. However, the last four digits of the number on the close-captioning are 4275.
To draw the 200 kilowatts the show speculated, the criminals would probably have to have over 500 computers. While they wouldn't have to be huge (physically), where exactly were these?
If the kidnappers asked for an algorithm to implement uses of Riemann's Hypothesis in integer factorization, they would be given an algorithm, not the 'fake key' that the FBI made up.
Charlie: (about the Riemann hypothesis) You- you've just asked me to solve one of the world's biggest mysteries in a few hours.
Don: Charlie, you got me thinking you can do anything with numbers.
Charlie: No. What do you think we should do now?
Don: Well, the same thing I did when I was in school, and I didn't know the answer. Fake it.
Alan: How is it I always end up loading the dishwasher?
Charlie: You were the one that wanted to flip a coin.
Alan: Yeah, I know, but I lost the last five times. Now what's the odds of that happening? Never mind, don't tell me.
Don: Relax, I got a great apartment in a great neighborhood... you'll find one, too.
Charlie: Then why are you over here all the time?
Alan: I just don't think you realize what you're getting yourself into.
Charlie: Yeah, how's that? I've lived here pretty much my whole life. I think I'm used to it by now.
(The furnace begins to rumble in the background.)
Alan: (smiling) Ah, that would be the furnace in your newly acquired home. There's a wrench in the basement... I'm sure you can figure it out.
Charlie: Okay, what's the biggest number you can think of?
David: A gazillion? Is that a real number?
(Charlie chuckles, and then suddenly stops.)
Due to time, a short scene was cut where Terry was expressing her anger over having Ballard slip through her hands twice, and not letting it happen again. It was supposed to happen while they're inside the van outside the house.
This episode was meant to play 6th, but was pushed up to 5th by CBS.
This episode was rated TV-PG (V).
Crew Clarifications: Walter 'Bud' Scott (1st Company Grip), Blake Smith (Assistant to Brooke Kennedy), Liz Radley (Video & Computer Playback Supervisor).
Czech Republic: June 23, 2008 on TV Nova
Slovakia: October 8, 2009 on JOJ
International Episode Titles:
Czech Republic: Základní okruh podezřelých (Principal Circle of Suspects)
Riemann's Hypothesis: First formulated in 1859, this is an unsolved math conundrum dealing with the number of zeros in Riemann zeta function.
367 Dahlia Avenue
The kidnappers' address is a subtle reference to one of Los Angeles' most notorious unsolved murders. Elizabeth Short, a young woman known as the Black Dahlia, was murdered in 1947 and her body was dumped in a vacant lot in downtown Los Angeles. The crime has generated a lot of speculation as well as many books, movies, and articles.
The Clay Mathematics Institute is dedicated to increasing, disseminating and supporting mathematical research. They fund a $1 million prize for a solution to each of seven major as yet unsolved problems in Mathematics, including the proof for the Riemann Hypothesis. So far only one of these problems have been solved, the Poincare Conjecture was proved by Grigoriy Perelman who was awarded the prize in 2010. The P vs. NP problem Charlie was working on is another of the Millennium Problems.
The Challenge Of Large Numbers
Charlie refers to a 1977 article printed in Scientific American where three mathematicians issued a challenge to factor a 129-digit number. The answer didn't come until 1994.