Another contributed explanation

The next scene sees Abe on the roof of a building, he's looking out over the park bench where Aaron is sitting. He's in the power position denoted by him looking down over the world. He knows how this day will pan out. This is the first time Abe has returned from the future. Let's call him Abe_1. As we'll see in a few seconds, there are now 2 Abes in this timeline.
The other thing to notice here is the sound of the ocean and waves as Abe enters the roof. This is an audio cue signifying time travel. We'll learn this later when Aaron and Abe discuss the dream they each experience whilst in The Box.
Abe_1 approaches Aaron who's sitting on the bench with a radio earpiece in his ear. He's listening to NCAA basketball. In the next few scenes Aaron continues to wear this earpiece.
I took note of the neckties they're wearing to ensure they stayed consistent and we didn't switch from Abe_1 back to Abe at any point.
Abe wants Aaron to ditch work and go visit Bradshaw, an engineer. On the way out of the office, they split up and Aaron goes to inform Will that a meeting has been cancelled. We learn later that Will is Rachel's ex-boyfriend's cousin.
In the next few scenes, Aaron learns that a protein has grown on their weeble. Normally this protein takes a long time to grow, theirs has grown in a short time.
The entire time, Aaron is wearing his radio earpiece in his left ear, the same ear which will later begin bleeding.
It's 2:05pm when Abe_1 describes to Aaron what's happening to their Weeble in the small box.
it's experiencing the same second, over and over again.
We also learn that the original purpose of The Box was to "degrade gravity". This is not important except that when this audio of Abe talking is played, it sounds distant like it might be on Aaron's earpiece. This hints, as we'll learn later, that this might not be Aaron but it might be an Aaron from the future!!! I don't buy this though as Aaron's writing (on the pad) is normal. He's not writing like a baby (we learn later that time travel degrades your handwriting).
Time between the A and B ends of The Box represents 1 minute. If the Weeble enters at the A end spends 1 minute realtime in The Box and leaves at the A end, it'll experience an even number of minutes, i.e. 1334 minutes in the movie. If it enters at the A end, spends 1 minute in The Box and leaves at the B end it'll experience an odd number of minutes in The Box. i.e. 1347 minutes in the movie.
They've accidentally discovered time travel here and the description is somewhat reminiscent of some of the Quantum mechanics books I've come across.
So in the next few scenes, they decide to build a bigger Box so that they can go in and control which end they get out of The Box. Abe_1 plants this idea in Aaron's mind, a classic "time-travel movie paradox". So far this is typical Marty-McFly time travel stuff. The basketball scene in the yard ends with Aaron saying "we're going to have to move it", Abe_1 responds "We will".
Next up they're sitting on the truck bed beside the storage facility. Abe_1 continues to plant the idea of how the machine will be built into Aaron's mind.
When Aaron says "You know what we could use", Abe_1 switches from pretending like he's Abe into the mode of being Abe_1. He knows Aaron is about to see regular Abe  enter the facility and he must brace Aaron for what he's about to see.
Aaron is NOT wearing an earpiece at this point. Again, this indicates he's regular Aaron, and not an Aaron from the future.
Aaron sees Abe enter the facility. The camera switches to a view of Abe_1 and Aaron watching the facility. This shot hints that they might be being watched by another version of themselves but I think this is another red-herring.
Abe_1 and Aaron enter the facility and wait until Abe has entered The Box. They sit beside The Box in a very poignant moment.
Aaron says "What did you do all day, the first time through", indicating that this is not Abe_1's first time coming back and hence he's technically not Abe_1, he might be really Abe_n. We can't know what revision he is though and it's not important.
Aaron wonders what he did that day and it's interesting that Abe_1 doesn't know either although after thinking about this, I don't think this matters.
During this conversation, the phone rings and Abe_1 answers. It's Rachel. The fact that the phone rings and he answers is OK as since Abe has entered The Box, then there's no loop.
Also, at this point, there's only 1 box in the storage room. I assume though that since this is not Abe_1's first time through, that he must have built the failsafe device and it must already be running in it's own storage room.
FAILSAFE SAVE POINT!!!
In the next few days they build a second box (Aaron still doesn't know about the failsafe) and then prepare for them both to make a trip.
So The Boxes work like this. The second you start The Box (8:45am in this scene) is the time you'll exit, regardless of when you enter. You must shut The Box off before entering and you must enter before The Box fully winds down. You must also exit The Box right when it's started, hence the stopwatches and alarms. If you exit too soon, you might go into a coma (I assume). To avoid being at The Box when your double exits, they use timers to give themselves time to leave. The time is set for 15mins and started at 8:30am. When 15mins is up, The Box starts up.
Abe_1 says "There are always leaks". Not sure what this means but it might be a hint of things to come. Fractures in their relationship and trust.
They drive to Russelfield to check into a hotel. This is to avoid affecting the world whilst they're traveling back in time. In the hotel they play Scrabble and Aaron tries to use all his letters and place a word that does not exist "Evacipate".
On the way back to the storage facility, for their first trip, Abe_1 checks the lock on a storage locker. Then moves to the real storage locker. Is this the locker holding the failsafe device? We learn later that the failsafe is in a locker upstairs from this one. Another diversion from Shane.
Right before Aaron enters The Box for the first time, he reads a piece of paper. It roughly reads:
"Rules to Follow to Evade Causality Paradoxes or Generally Screwing Your Life Up"
1. Do not disturb The Box after you exit as you or your double is in it.
2. When re-experiencing time, stay away from your double until he/she has started his/her journey backwards.
3. Worry about yourself first. Now is the only moment that has to make sense.
They enter The Box and we hear faint hint of waves in the distance along with the hum of The Boxes.
They get out just as the machines are starting up, at 8:50am. Abe says he left the machine on since he or his double or "someone" was on the way back. Who's "someone"?, why would he say that? Did he tell Granger about The Boxes in order to get funding and did he have Mr Granger try one out?
They decide to trade some stock and make some money using mid-cap funds to avoid getting caught. Later that day they drive back to the facility, park and watch their double's going into the facility, just for kicks.
In the next scene, Aaron's wife Kara complains about rats in their attic. Aaron claims they are birds and to leave them alone. He must know at this point that the noise in the attic is actually his drugged double. If he hadn't been up in the attic he'd be supportive of getting the exterminator. I mean, who wants rats? This means Aaron at this point MUST be an Aaron from the future.
Aaron also suggests using the time machine to punch out Platt. Another Paradox! He wants to go to see Platt, punch him and then enter The Box, go back in time, go visit his double before punching him and then convince him not to do it. The problem with this is even if he manages to convince himself not to punch Platt, he must also convince his double to go enter The Box. It's basically an experiment to see what would happen. He'd have punched out Platt and yet not punched him out. There's no point other than curiosity and the idea has been planted by an Aaron from the future.
The gas-pump scene is when Aaron breaks down a little to Abe, he's talking about life, the way things have worked out, what if this is your first or second time through etc. One of the great lines in the movie: "What's worse? Thinking you're paranoid or knowing you should be?". I presume he's talking like this as he's secretly from the future.
Abe is beginning to suspect Aaron.
In the next scene, they've been back through obviously, they're trading stocks again and discussing telling Aaron's wife. They decide to not tell Roger and Phillip.
After a few more trips through together and a discussion about Aaron's dream, Aaron begins bleeding, presumably from excessive time travel or being awake for so long. He's been traveling through with Abe and also on his own.
In the next scene, Abe is in the garage when Roger and Philip come in. Roger thanks Abe for the present. We learn later on that Abe bought Roger a vinyl record of the "Best of Bread". Roger states "you guys make fun, but there's a difference", implying the superior quality of records over CDs. Roger refers to Aaron as "Hero". Abe doesn't notice at first but then realizes. What follows is an explanation of the events of Roger's birthday party when Aaron rushed Rachel's ex-boyfriend.
NOTE: Abe wasn't at the party in this timeline, so he needs Roger to explain the "hero" incident.
Abe didn't know about the party as Aaron didn't tell him. The birthday party was on the night when Abe_1 first explained everything to Aaron. Abe_1 and Aaron did NOT go to the party originally. This re-inforces the idea above that Aaron is an Aaron from the future. I'm going to refer to him now as Aaron_x as I'm not sure which revision he is. We learn later that it took more than 1 try to get the Birthday party incident correct. We also learn that even when Aaron_x wasn't there noone was hurt. Aaron still desires praise so he figures he'll reverse engineer it by changing how the party plays out.
In the waterfall/garden scene, Aaron_x says "things are different right now". He's referring to the power to revise that they now have.
Aaron_x and Abe are in the hotel room when Aaron_x's cell goes off. He answers the phone and it's Kara.
They go back. There's a great line in next scene. They're sitting in a room, Abe is meticulously slicing a cupcake and Aaron_x says "Are you hungry? I haven't eaten since later on today". It's also interesting that although Abe and Aaron_x are watching a sports game, they both know the outcome. They're clearly not following the original rules of switching everything off and unplugging stuff.
They go for food and are walking down the street at the same time when the original phone call was placed by Kara. Aaron_x took the phone with him (by mistake) and it goes off again. Thus, the question, did it really go off in the hotel room? And did he answer it? Another paradox.
Next things get sketchy. Abe is woken by a car alarm. He decides to do an experiment, to go back in time with Aaron_x and prevent himself being woken by preventing the alarm going off. Thus creating another paradox.
He tries to tempt Aaron_x into going along with this by offering him the Platt face-punch. Abe also reveals he's been turning The Boxes on at 5pm. This is bad as he's didn't tell Aaron_x and he's potentially using the boxes without Aaron_x's knowledge.
They leave and notice Granger is following them. They call Granger's house, he's there! This means that Granger has gone back in time and the future Granger (Granger_1) is in the car. They give chase and Granger_1 falls in to a coma when Abe gets near him.
Something has happened between Abe and Granger. They're asking "what did he change?" They might be referring to Granger here or the might even be referring to a revision of Abe!. Abe decides he must use the failsafe machine. The failsafe's been running for 3 days 22hours when Abe uses it.
Let's now call Abe from the future Abe_2. The next few scenes are pivotal.
Abe_2 goes back and gases Abe_1 whilst Abe_1 is asleep!!! Abe_2 then attempts to meet Aaron on the parkbench as Abe_1 originally did. He passes out as he's just spent 4 days in The Box.
Aaron is no a revision from the future. We know this as Aaron is listening to a tape and responding according to the tape.
"At this point there would have been some...discussion".
Abe want to know "how". The how here is how everything has happened, here's my take:
After originally meeting Abe_1 on the parkbench, Aaron saw the manifest and found out about Abe's failsafe. Aaron decided to take a box with him through the other box thus creating 4 boxes and his own failsafe. In order to get back to a point before the parkbench, he must have used the failsafe, hence breaking the original assumption that they are single use only.
At this point he had lost trust in Abe and was operating alone.
Aaron then went into a loop of trying to be a hero at the birthday party. He recorded the days events just in case his first attempt at the party failed, attended the party by himself (without Abe), tried to rush the ex-boyfriend but things went wrong. So he had to try again.
In order to try again, it meant going back to that morning, then playing things out just perfect so that the party would still have a scuffle. He'd use the audio tape for this.
The problem was that the party was on the same day that Aaron originally met Abe at the bench. It wasn't a day when Aaron had been stuck in a hotel as with the other days. So Aaron had to somehow take his own place that day.
The second time through, he meets the "Hooded Aaron" who is the one who has used the failsafe. This failsafe was setup when Aaron took a box back through the other box (after finding Abe's failsafe).
The hooded Aaron has already drugged his double and put him in the attic. We know he came through one of the failsafes as his beard has a few days growth on it. Hooded Aaron leaves as his whole intent was to record the days events and become the hero at the party.
So things play out from here. Abe is now Abe_2 from a few days in the future and Abe_1 has been gassed and is stuffed in a room adjoining a bathroom. Abe_2 doesn't know that Aaron0 is in the attic!
Original Aaron0 is up in the attic.
Aaron in the white-shirt has been looping through this day for a while, trying to get the hero thing to work. He knows Aaron is in the attic and hence tells Kara that the rats in the attic are really birds.
There's also hooded shirt revision of Aaron who has just left! I guess he's gone off somewhere.
They both continue repeating this day until it comes off just fine. We even see Abe with his own recording at the party. The best part is that nothing happened originally when they weren't there, or maybe it did, we don't know.
In the end, we see a version of Aaron talking to Abe_2 at the airport. Abe2 has found out about Aaron in the attic. He's pissed. He decides to send Aaron on his way and stay and watch over Aaron and Abe to ensure they never build these boxes.
We later see either Aaron or hooded Aaron in France building a room-sized box.

I'm not sure this explanation works, but it seems the movie is left open to interpretation. It's a puzzle.

An explanation contributed

Primer plot summary

Aaron, Abe, Philip and Robert work by day at some major firm and sell home-made electronic products in their spare time. But while they've had some interesting patents, they haven't made major money from the side projects. (In fact it's implied that a man named Joseph Platts stole one of their patents and/or some of their money.) It's been agreed that each guy can put something forward to work on when their turn comes. Robert's idea is to build a strange piece of hardware which can theoretically reduce the mass of an object inside it. This is just after Christmas time (hence Aaron's new refrigerator).
The box requires superconductivity. They can't generate the low temperatures they need, so in the brainstorm session they throw out an idea or two for doing it at room temperature. They cannibalize a catalytic converter for palladium, and build the thing in Aaron's garage.
Later, Aaron and Abe realize that much of the design is extraneous because the device they've built appears to work perfectly. While fiddling with the device, Aaron pokes his hand right the way into the field and Abe puts his hands over it to drop punched holes into the field. This becomes significant later. The box has to be hermetically sealed to outside observation. They flood the box with argon and register the decrease in mass of a blue weeble put inside. Then the box seemingly malfunctions in some way.

*

We then jump forward a little. Now Aaron has done something to the box to make it work properly. In fact, it appears to be putting out more power than is even being put in. After the power is shut off it continues to run for a few minutes. This could be due to the superconductivity in the machine but Aaron and Abe seem to think that it is something else. Aaron and Abe instantly recognize the potentially gigantic applications of the device they have built and decide to cut Robert and Philip out of the loop entirely, saying that the garage has to be fumigated.
Several months pass. They get funding from a Thomas Granger, while Abe establishes a relationship with his daughter, Rachel. (Aaron is of course happily married to his wife Kara, with a daughter, Lauren.) Abe tries and fails to figure out how, exactly, the device does what it does.
Then, in quick succession, quite a lot of things happen. After repeated experiments on the weeble, Abe realizes that a weird fungus is growing on it. He takes it for analysis and is told that the fungus is perfectly ordinary, but the amount of growth he has seen is consistent with years of time passing, not days. He then tries it with his watch and concludes that what they have built is a time machine.
Abe figures out how to build a coffin-sized time machine. He builds what we shall call Box A and places it in a unit at a self-storage facility.
This is now March.

Monday

At 08:30 Monday, Abe primes Box A to activate itself in fifteen minutes. He drives away from the self-storage facility and isolates himself at a hotel in Russelfield. The box activates at 08:45 and is completely powered up at 08:49.
At 15:15, he returns to Box A and switches it off. It takes another four minutes to power down completely. As it powers down, he climbs inside. He waits for what is repeatedly stated in the movie as being six hours - actually it is six and a half. At the correct time, he climbs out of the box just after it was activated (i.e. just after his other self walked away), at 08:45. While his double is sequestered, he goes to Aaron, who is listening to March Madness on an earphone (and continues to do so for the rest of the day). This is the first bench scene.
Abe walks Aaron through the precise series of evidence that led him to the conclusion that the box is a time machine - the fungus and the watch experiment. Finally, at about 15:15 Monday, he brings Aaron to the self-storage facility and they watch just as Abe's double arrives, gets into the box and disappears entirely.
Aaron is now also convinced.

Tuesday

Abe shows Aaron that he cunningly made a single excellent stock trade during the Monday too.
Abe goes through the same routine but this time Aaron insists on following along. By now, Aaron already has his own box built.
They switch on the boxes at 08:30 Tuesday, hide at the hotel all day and then return to the boxes at 15:15. Abe departs the box at 08:45 Tuesday as expected, but Aaron gets jumpy towards the end of the ride, and exits a minute or two early (or, from Abe's perspective, a minute or two late), suffering a severe physical reaction. The time is 08:50 Tuesday morning.
The dialogue during these scenes reveals a few more noteworthy facts.

• Abe and Aaron are both operating under the assumption that there is most likely a single paradox-free timeline. They isolate themselves at the hotel solely in order to prevent the possibility of paradox. In particular, anything that could prevent their doubles from departing the timeline as scheduled would be a major problem since it would result in multiple Aarons/Abes running around, permanently.
• The other important line is "the boxes are one-time use only". What Aaron means by this is that after you have climbed out of a box, you CANNOT go back to it later, switch it off and climb in a second time - because that's what your past self did. You CANNOT use the same box to continuously loop through the same day.
  After a great deal of thought, I have come to the conclusion that this is not actually true. For the purposes of this plot summary, however, all we need to know is that Aaron and Abe both believe this is true and operate under this assumption.
  

They make some more money on the stock market and that evening they have a slightly drunken conversation with Aaron's wife Kara about the prospect of having unlimited money. Aaron raises the hypothetical of punching Joseph Platts in the face, then going back in time and making it so it never happens. Abe says they "can't do that", not because it's morally wrong to punch Joseph Platts in the face, or because Aaron can't tell Kara about the time machine, but because at the moment they are both operating under the assumption that history cannot be changed.
"But the idea had been spoken. And the words wouldn't go back once they had been uttered aloud."
Kara also mentions a mysterious noise in their attic. Birds? Rats?

Wednesday

The same routine again.
They argue at the supermarket and the gas station that morning about paradoxes, free will, paranoia and predestination - specifically, the problems of living in a predestined universe which was made that way by somebody else. At the hotel, and then later on Wednesday afternoon at the library, Abe and Aaron discuss the problem that Aaron is keeping the time machines secret from Kara. They also discuss the problem of keeping them secret from Robert and Philip, and agree to give them a certain amount of patent rights and/or equipment and/or cash in order to salve their consciences instead.
They loop back in time as normal. At 08:15 Wednesday, shortly after getting out the machine, Aaron is bleeding from his ear.
That day, make their successful trades. In the afternoon, they finally admit that the garage has been "sprayed", and work at the garage with Robert and Philip resumes. Robert and Philip have now received their gifts from Aaron and Abe.
Robert reports an interesting story. It seems that Monday night was Robert's birthday party. Abe wasn't there, but his girlfriend Rachel was there. So was Rachel's ex-boyfriend, who walked into the party brandishing a shotgun. So was Aaron, who by all accounts risked his life to defuse the situation safely.
On Wednesday evening, while Aaron and Abe are outside looking for Aaron's missing cat, Abe is angry that Aaron, a family man, risked his life in such a way, and genuinely confused that Aaron acted so uncharacteristically irresponsibly. Aaron makes excuses and claims that since the discovery of the time machines he is seeing the world differently, referencing their conversations of earlier in the day. But this does not fully explain his actions.

Thursday

The same routine again.
During the day spent at the hotel, Aaron's cell phone rings. It is Kara, asking about dinner. This is a mistake, since Aaron is supposed to be sequestered. Abe tells Aaron not to bring the cell phone back in time with him - this is a perfectly sensible way to avert the possibility of a paradox.
They loop back in time as usual. On the second time through Thursday, Aaron watches a sports match (whose outcome they already know) while Abe eats a muffin. Then, on the way to a restaurant, Aaron's cell phone (which he has foolishly brought back in time with him) rings again.
This is a problem, and a critical turning point in the movie. There are two Aarons at this point (one at the hotel), and, due to Aaron's clumsiness, two of his cell phones (one at the hotel). If the phone in Aaron's hand is ringing then, so Aaron and Abe reason, the phone in the hotel cannot be ringing. Symmetry is broken and history has changed. History can be changed.

Friday

At about 02:00 on Friday morning some kids set off car alarms outside Abe's home. Abe goes to Aaron's house and gets him out of bed. Abe reveals that he has been routinely turning the boxes on at 17:00 and turning them off the following morning.
Abe then puts forward a confusing and potentially dangerous plan to visit Joseph Platts at his home, punch him in the face, then, around 03:00 Friday, to use these boxes to go back in time to 17:00 Thursday and make sure that neither the car alarms nor the punching happen. In theory, as a result, both Aaron and Abe's doubles would stay in bed all night, get into their boxes at 15:15 Friday as normal, and leave this timeline permanently, leaving just one of each of Aaron and Abe behind.
It is not clear whether this plan would work or not.
As they climb into the car, however, they realize they are being followed by Thomas Granger, Abe's girlfriend's dad and the project's main source of funding. Granger has several days' growth of beard on his face - but Aaron last saw him at 18:00 Thursday, when he was clean-shaven. Abe phones Thomas Granger's number and the guy who answers is indeed Thomas Granger... but he's not the guy who is following them. Something really weird is going on. This man is a different Thomas Granger who has come back in time using one of the boxes, probably exiting the box at 17:00 Thursday when Abe switched them on. Aaron runs after Granger and when they get close to one another, Aaron trips and falls while Granger falls completely unconscious. They put Granger to bed at Abe's house; Aaron cannot approach him with actually somehow knocking him unconscious. They check that the boxes are indeed turned on. Aaron proposes shutting them off to see if Granger is inside, an act whose consequences would be exceedingly difficult to guess at. They do not do this.
Why has Granger come back in time? Obviously at some point in the future, Aaron or Abe told Granger about the boxes. Then, something happened to prompt Granger to head backwards in time to this point (the earliest he can go) and start observing them. They conclude that the situation would have to have been a real emergency but they have no clue what it could possibly be. "The permutations were endless." History has definitely changed now that Granger has come back, but they have no way of guessing whether the emergency in question has been fully averted by his brief interactions with them and the rest of the universe - he has only been out of the box for about eight and a half hours.
And so Abe loses his nerve.
It is now revealed that there is a failsafe box, built by Abe, in a second storage unit. This box has been running for 3 days 22 hours - in other words, since early on Monday morning. Abe started the box at about 05:00 Monday, then went back to bed until 08:30 when he returned to start Box A. At roughly 03:00 Friday, Abe returns to the failsafe box, with four days' oxygen and water and a small tank of medical-grade nitrous oxide, enters it and travels all the way back to 05:00 Monday.

Monday again

Abe (now Abe Two) exits the failsafe box at 05:00 and gasses his double in bed with the nitrous oxide. He stashes his double in his bathroom.
Now we come to the second bench scene. As in the first bench scene, Aaron is listening to what is supposedly basketball on his earpiece. Abe Two is ill, after four days of very little food, and in shock, after violently gassing his double. Aaron, however, repeats most of the same lines as last time.
In fact, when Abe faints, it is revealed that Aaron is not listening to basketball. He is listening to a recording of that very conversation. How can this be? The recording must have been made in some previous timeline. This is not the original Aaron. This is not the original timeline. It never was. This Aaron has come back in time from the future.
"At this point there would have been some... discussion."
Aaron and Abe confront one another and explain everything that has happened. This is the most difficult sequence in the movie to follow, partly because of the complexity of the plot but mainly because, due to the lack of CGI, it was impossible to put more than one Aaron on the screen at the same time. The two major discussion points are:

1. How?

   Aaron's line, "They are not one-time-use only. They are recyclable," means that although you cannot re-enter a box you climbed out of, you can bring another box with you, activate it once you climb out, and later use it instead, traveling back to the same moment in time again - or a few minutes later, at any rate.
   In some previous timeline, Aaron discovered Abe's failsafe box, anchored 05:00 Monday. He then got inside the failsafe and used it to go back in time, taking with him a second, folded-up time machine. This is the Aaron with the hood.
   On arriving home at 05:00 Monday, Hooded Aaron set up his second time machine as Failsafe Box B, let's say at 05:15 Monday. Hooded Aaron then went to his home and drugged his double's breakfast cereal milk, then stashed his comatose double in the attic. This is the noise that Kara mentioned on Wednesday night. This means that there are now two Aarons in this timeline, permanently. Hooded Aaron assumed his double's identity and recorded all of the week's conversations.
   Then, he used Failsafe Box B (remember: he cannot re-use Failsafe Box A since he already climbed out of it once) to go back in time to 05:15 Monday yet again. He took yet another time machine with him, which he set up as Failsafe Box C (05:30 Monday). He becomes Aaron Three, with the white jumper, no hood. Aaron Three arrives at his house just as Hooded Aaron has finished drugging and stashing Aaron Prime. Aaron Three tries to subdue Hooded Aaron in turn, but this time he is too exhausted, and Hooded Aaron wins. After a conversation, however, Aaron Three persuades Hooded Aaron to leave. There are now three permanent versions of Aaron: Aaron Prime, who is drugged in the attic; Hooded Aaron, who has left town; and the Aaron we have been looking at since the beginning of the first bench scene, with the headphone in his ear feeding him lines, is Aaron Three and always has been.
   Aaron Three has had a LOT of exposure to the boxes. This is why he began bleeding from his ear on Wednesday, and it also why his contact with Thomas Granger nearly killed him.
   It is Hooded Aaron who is the narrator of the story, or rather the person making the phone call.
   So which box did Abe use to come back in time? Logically, Abe must have used Failsafe Box C, since Failsafe Box A contained Hooded Aaron and Failsafe Box B contained Aaron Three. How did that happen? Aaron must have SWAPPED Failsafe Box A and Failsafe Box C. The box that Abe believed was Failsafe Box A (anchored 05:00 Monday) was actually Failsafe Box C (anchored 05:30 Monday). This is not seen or even alluded to in the film, but it is necessary to resolve this plot hole.
   

2. Why?

   Problems of logistics aside, the last remaining question is why Aaron chose to come back in time so far, sacrificing so much, permanently duplicating himself twice. What is he trying to set right, exactly?
   The key to all of this is the party. It is obvious, though left largely unsaid, that when Rachel's ex-boyfriend walked into the room with a shotgun, things could have gone considerably worse. Aaron Three, we remember, risked his life to successfully defuse the situation. We now understand why he would take this risk. There are two other Aarons in this timeline, one of them being Aaron Prime. Aaron Three does not matter - he is a non-person, a walking dead man, and he has no right to Aaron Prime's family. He has no life to risk.
   If I may jump ahead in the movie slightly, the basketball scene (which takes place sometime in the middle of Monday) is also important. This scene additionally establishes that it was Aaron who originally invited Will, Rachel's ex-boyfriend's cousin, to the party - and that it was Aaron who suggested that Will should bring Rachel's ex-boyfriend with him. In other words, whatever originally happened at the party was indirectly Aaron's fault. He holds himself responsible. This is why he has done what he's done.
   

Aaron Three thought the problem permanently settled. But the fact that Thomas Granger came back in time to 17:00 Thursday indicates that it was not, and something bad was still looming in Aaron and Abe's future. However, it is Monday morning again, and both Aaron Three and Abe Two are prescient now. They decide to engineer the situation to end better this time, with Rachel's ex-boyfriend actually arrested and jailed.
By Monday afternoon, Aaron and Abe are both suffering from the effects of a great deal of time travel - they are unable to write correctly.
At this point, the narrator, Hooded Aaron, reminds us that HE, of course, does NOT come from a timeline where everything worked out perfectly. Hooded Aaron has only been to the party once, and he has only seen how it originally played out. He has no idea how long it will take for Aaron Three to "reverse-engineer a perfect moment". From what we see in the movie, though, for Abe Two and Aaron Three, it appears to work first time. The jealous ex is arrested and jailed. The End.
On Monday night Aaron Three crashes at Abe's house. Abe Two cannot sleep. And with that problem resolved, everybody lives happily ever after.
With the following exceptions.

Tuesday again

Aaron Prime wakes up in his own attic after being drugged for 24 hours by his double. Abe Prime wakes up in his bathroom after being gassed for 24 hours by his double. There are three running failsafe boxes which evidently nobody has thought to shut down, in addition to Abe Prime's original Box A, which hasn't been activated yet but is nevertheless operational. "They'll be building their own boxes in another day. And [Abe Prime] already knows what they built."
Aaron Three and Abe Two wind up at the airport. Aaron is going to steal his double's passport and leave the country, because he can never go home. He has lost Kara and Lauren to Aaron Prime. Abe, meanwhile, is going to stay behind so he can sabotage their doubles' attempts to build the time machines. And, more sinisterly, stay close to Kara and Lauren. And protect them from Aaron Three. What?
And finally, on the other side of the world, Hooded Aaron makes his phone call to Abe Prime. Hooded Aaron explains the entire story, including why they drugged Aaron and Abe, and thus "[repays] any debt I may have owed you".
"You will not be contacted by me again. And if you look, you will not find me." Hooded Aaron hangs up, and begins construction on a time machine the size of a warehouse. The End.

Credited to Sam

Back Again

I haven't posted here in a long time.
I thought I would include a few web pages from others that are respectable.
I don't want to add them at The Primer Universe because the book stands alone.
Too much additional information leads to confusion.
If you want any information on old deleted pages, drop me a line.

N's Timeline

Click to expand

Nuewanstein's Timeline

It is a little harder to dissect this theory as it is only a visual aid and not a full-blown explanation. As to its background: there is no claim or other pages tied-in with it. Which leads to belief in the rumor that it was intentionally named this and posted by one of the members of the film crew. This would explain why anyone with this much intelligence would start the action in September (when filming was completed in 2001 and edited over the next two years) rather than December or March as clearly seen in the film.

Neuwanstein refers to King Ludwig, which is German (as in this sites web address), and his castle which was the model for Disney's fantasy castle. Thus some refer to some fantasy ideas as a Neuwanstein. Is this then just pure fantasy? A constructed framework that intentionally withholds the real key to solving Primer while demonstrating the kind of action that occurs due to the constraint and freedom allowed by the time machine's in Shane's film? Very likely. That being said, we should focus more on what we can learn from this timeline diagram rather than pointing out that it fails to properly explain the Granger Incident, the recording Aaron, and the fail-safe counter-actions. There are so many actions to relate that a visual timeline would be so complicated and have so many variables or permutations that it would become nearly impossible.

In the original timeline, we truly only know that Aaron must find the fail safe and use it. Other steps can be deduced but without any guarantee. If Aaron finds the fail-safe in this Abe-controlled timeline, then he can gain control of the boxes depending on what he does upon his exit. If I were to have a timeline (like the one in my head) it would be similar to N's but I vision it as rolled into a cylinder. Now picture that each use of the time machine can land one in any timeline (not just from d to e or c but across the cylinder like e to b). In other words, when Abe fail-safes after the Granger Incident, he lands in a timeline where Aaron has control. Thus when Aaron uses the box in this timeline, this Abe is affected. With only one time traveler it remains simple; every use of the box resets the timeline or begins a new timeline. When there are two time travelers, one can never know if he lands in a timeline in his control or the other person's control. For example, if Aaron redoes the party 19 times, then Abe only lives it the 19Th time and all other 18 replays are lost. Abe is not conscious of anything except party number 19. Abe does not have anyway of knowing that Aaron redid the party 19 times. Now if Abe fail safes the next morning and goes back 48 hours, then the Aaron of this timeline is likely to repeat the upcoming party 19 times also. Unless Abe has some way to avoid or alter the events that caused Aaron to redo the party. (Perhaps he could call Rachel or her ex-boyfriend and ask him not to come, etc. Or if he finds out that Aaron repeated the party for whatever reason, go back 48 hours and instruct him how to get the party right the first time. There is also the opposite circumstance. Suppose Aaron found the party to be a bore fest. Then he travels back a day, invites the ex to liven up the party and could go back and replay the party until some major event crops up. Then Abe could be going back to try to undue the effect of the prescient Aaron.

Neu also seems to think that there are 'three' rooms at the storage center with boxes and that Aaron takes 'two' boxes with him. Then he moves the original box into another room 'without unplugging it' and sets up a new box in Abe's room. This will not work logically. First, you can't keep the box running and move it at the same time. (Carruth does not show the boxes plugged in because the storage unit that was used for filming did not have electricity in each unit. We are shown only two rooms on the manifest, not 3.) Neither is there any reason to take 'two' boxes back, nor the room to stuff it all in a box with yourself. However, in the new timeline created, the former Aaron will take a box, fold it up and disappear with it unless he is interfered with somehow. Stealing one doesn't automatically mean having an extra one as theorized by some people. ( like some guy who suggests putting money in the box. You only have twice as much until your double takes off with the original half. Bet the long shot with a perfecta or exacta at the track and you can get 100 to 1 odds. ) One must stop their earlier version from taking the box and disappearing with it in the newly created timeline. I am trying to work on a write-up of Neu's timeline, but it is tedious because I keep adding corrections and notes of errors, which is growing exponentially.

In conclusion, I feel I have demonstrated that this timeline did not come from Carruth. One thing is certain, if Shane had a clear picture of what was really going on without any plot holes; he should have filmed it and sold it as a separate film. At this point, a new commentary won't stimulate enough interest to make it worthwhile. His alleged upcoming book, an possible attempt to usurp the Primer Universe, may prove to be several years too late. True, it may contain pictures that he wouldn't allow to be used in the Universe book without cost. I only hope that he learns that it would be depreciating to produce an autobiography of his own film. Shane might not like the answers being 'thrown around for free' and especially that the book has 'gone rogue' as a free publication. Its being a taboo publication only heightens the curiosity factor. After all, there are a hundred attempts to explain what happened. Only one of them has been discussed by Shane. Only one remains.

Review of Gendler

Review of Jason Gendler's report on Primer.
Title: 'The perils and paradoxes of restricted time travel'

This discussion of Primer is generally acceptable, somewhat interesting, and admits to not understanding many key parts of Primer's secrets. It is apparent that the writer tries valiantly to impress us with extensive vocabulary. He tries very hard to differentiate the story into fabula, syuzhet, and non-chronological syuzhet. (One spelling error mentions putting a "weevil"(sic) into the time machine, rather than the Weeble.This is just a submission to a self-proclaimed intellectual internet magazine, not the New York Times.)

One thing I liked is his retelling of what we see on-screen during Primer.(although this part seems unnecessary to anyone who has already seen the film.) It is three pages long, but provides a great review of what is seen for those who haven't viewed the film recently or perhaps have had only one viewing. I am glad he agrees with me on one of the things many fans miss: during the conversation between Abe and Aaron with the small version of the time machine we hear a sentence coming from Aaron's recording playing through the earpiece. Most people claim it is just muffled dialogue, but it is nice to know it is not overlooked by everyone. (Jason marks it as 24:33).

Jason feels that the narration omits crucial details to understand everything that happens in the film. Yet, he looks to camera work(What??) to unveil his version of the story. He claims that time travelers are 'immune' from paradoxes but neglects to relate why his speculation does not apply to Granger.
A minor mistake is the frequently misidentified phone call which he states is "Aaron2 to Aaron1". It has been verified by Shane Carruth that this is Aaron2 calling Abe1 ( as in "The Primer Universe".) Carruth seldom will ever discuss these type of secrets, but I think he admitted this detail as Primer fans had already identified this correctly at the time.

Jason admits to being unclear which Aaron is seen in the film's ending. He claims that one can time travel "forward" and "backward" but clearly he just did not edit this sentence properly.( One could state that sitting in any cardboard box is 'time traveling forward'. Obviously, he just misspoke, easily forgivable. Blame the editor for not catching that error as well.)

Jason claims the bleeding ear and bad handwriting are because time travelers "shouldn't exist". This statement does not explain why this would not happen immediately to both time travelers. Jason expresses that the story is excessively complicated and clearly struggles with its difficulty. This is understandable. However, don't blame the director, blame the analyst.

Jason identifies the title Primer as the definition "a script". I think he meant to refer to: 'the elementary composition of the conversational structure' (an alternate dictionary definition), but was just a bit too quick to conclude his research of the title process.

Jason returns to his favorite subject: camera work. Due to Abe's statement that 'Parabolas are important', Jason goes to great lengths to find parabolas in the film. He focuses on Aaron with the basketball, identifying an 'elliptical path' ??? Then he describes the round water fountain as 'parabolic-shaped' ???(But a circle is not a parabola.) When the camera moves on a track, again a "parabolic manifestation"??? He overlooked Carruth's explanation for the tracks when he explained it was relatively cheap and made it easy to keep the camera in focus while moving. Jason feels that when the camera pans from left to right, time is going forward; while time goes in reverse when the camera pans from right to left. Why is left up to our imagination. This part is insane. How did this get accepted?

Jason sees 'jump cuts', but identifies them without any explanation. They are merely "bizarre". Later, he states they could be "an allusion to time travel". Yet the who, what, why and when are still a mystery. I like how detailed he is in identifying three shots out of order in the famous phone call to Abe scene. However, he fails to identify this as evidence of Aaron's time travel.

In his conclusion, Jason sees Primer as having "new and interesting ideas about the possibility of time travel". However, what fans want most, he describes as "conundrums that are open to multiple interpretations". Perhaps it takes a true fan, rather than a student from a film school to identify what needs to be explained about Primer. When this was written, Shane Carruth could at least know his secrets were still safe.(At least until 2008 when the Primer Universe book was released). This article didn't excite anyone in the Primer community (and for good reason). It lacks the depth that is needed. Even in his observations, he fails to clarify the purpose and intent behind the "mysterious movements" of the camera or basketball. It seems the film's "Byzantine nature" prevented Jason from having a clear analysis of the restrictions of time travel in Primer. Perils indeed.

Review of Goodwin

The first letter asks about reviewing other works on Primer. I will do a few over the next couple of posts.

Review of Jonathon Goodwin's report on Primer: "Sports, Repetition, and Control"

Jonathon's explanation and analysis of Primer falls woefully short. Credit him with a well-intentioned effort. His direction focuses on sports(?) as well as a mentally created reality(?) where each character rules the world as a god. This is probably the last thing any Primer fan may expect. Many will no doubt pass on this account without reading its 16 pages in any depth.

Jonathon claims that Carruth uses sports within the film as a metaphor for control. (Shouldn't the time machine itself represent a metaphor for control?) He continually returns to the subject of sports as if this was a central theme of the film.

He claims that Aaron built the first box. (Perhaps this is from misunderstanding how Aaron got control of the fail-safe from Abe.) Also, he refers to Rachel as "Abe's current girlfriend" rather than his former girlfriend. Rachel has a boyfriend at the party (the one in March). Jonathon also feels that Granger somehow created his own box. Another error is his misunderstanding of the scene where Abe2 gases Abe1. This error is common and is due to the restraints of the film's budget. This scene was filmed with David Sullivan and Shane Carruth standing in as Abe's double, so a discerning eye often sees Aaron in this shot. Carruth's commentary clarifies this situation. Finally, before returning to sports, Jonathon expresses that Aaron builds a large box to take "an army back in time". An army? Why not a football team? Where did this thought leap out from?

In his return to the 'main theme' of sports; he sees sports as "an instrument of social control." Then, in an apparent attempt to cover his bases, he adds that their interests in sports is a "simple realistic detail". What happened to the vital sports metaphor? In the next paragraph, he returns to the"greater meaning" of sports in Primer. It sheds light on "the nature of their previous friendship." Really? Apparently, Aaron is poor at sports because he not only misses one of the shots with the basketball, but also misses the wastebasket with one of his paper balls.( Oh, you may have missed this 'significant event'.) What does this tell the audience according to Jonathon? It shows that Aaron has less "material success" and "a lack of courting success." (It may appear he at times confuses Abe and Aaron)

Next, he relates that their competition in sports, including Scrabble, shows that there was an earlier struggle between the two for "Kara's favors." Another metaphor arises from their struggle with time. This metaphor represents 'unexpressed emotion'. So, to explain the "psychological conflict", the paper asserts that the use of Argon in the time machine represents the word agon.
More confusion arises from the allusion to Abe and Aaron being the same person, with Aaron being an avatar of Abe who is having an agon with himself. The plot has certainly thickened here, perhaps it has coagulated and has become unpalatable. This leads to the film's conclusion where Aaron "has hired Foreign Legion mercenaries in Africa to extend to the dawn of human evolution." Wow. I must have missed something.

Jonathon alludes to 'All the President's Men', mentioned several times by Carruth in interviews, but does little to show any link between the two films. Jonathon returns to speaking about Primer as having an unambiguous answer, but admits it lies beyond his grasp. He then misidentifies the company as "Amoeba" (sic), instead of Emiba. Also, he claims that the name Abram is significant.(He does not list its meaning which many people misquote, as Abram is a word that means 'one's father is elevated' (or his status is elevated through the birth of his firstborn, a son.). He describes Abram from the Bible as "an embodied paradox", apparently thinking that the name has meaning of self-elevating or in his words "priority". (Research , research, research: the three most important things in editorial review)

Again, we are told of the similarities of Abe and Aaron, with the exception that Aaron impregnated his girlfriend and was forced into marriage (this is stated without any basis.) After rambling off topic for a few paragraphs, we return to the film once again. There is a "metaphor" in the expression of different 'hemispheres'. This represents, in his opinion, "the emotional effect that the discovery (of time travel) has on their friendship." Was a metaphor needed for this? What evidence is there for this connection? What about the expression of Aaron's job at 'Cortex-Semi'? Shouldn't that represent something as well?
Primer leads to Abe and Aaron needing to decide if they should become the two closest friends or complete agonists. They have become gods in a self-created "private reality". Maybe he was watching the Matrix. Somehow, there is another "allusion.". This time referring to Rudyard Kipling's 'Conrad and the Heart of Darkness". The proof is that it shows that Aaron wants to fade the alternate time lines into a white sepulcher. Maybe, this draft by Jonathon should be entombed. It doesn't deserve the effort to review it. I hope you have been spared.