My theory: The Back to the Future film series only makes sense if you apply the multiverse theory to time travel. Essentially, Doc Brown did not invent a time machine, but a Ghaldron-Hesthor field-generator that allowed Marty McFly and others to move travel through the multiverse, but without realizing it, mistakenly referring it to time travel. I promise to break down each film to explain why it makes sense, starting with the first one.
The movie begins by introducing us to Marty McFly. Marty is a teenager who lives with his disfunctional family in Hill Valley, California. His father, George McFly, is constantly bullied by his supervisor, Biff Tannen, and his alcoholic mother, Lorraine Baines McFly, is very unhappy with her decision to marry George. Meanwhile Marty's brother Dave is a unambitious delivery boy and his sister Linda is likely the inspiration for Meg Griffin. Marty's life is not much better: his band failed in their audition to perform at the high school dance (for being too loud) and Biff crashed his car. Marty's girlfriend, Jennifer Parker, is the only bright spot for Marty despite his mother's dislike for her. If I were Marty I too would want to escape this reality.
At dinner, Lorraine recounts how she and George first fell in love when her father hit George with his car (sadly not killing him). On the morning of October 25, 1985, Marty meets his friend, scientist and Einstein-impersonator Dr. Emmett "Doc" Brown, at Twin Pines Mall (remember the name of the mall, it is very important) at 1:15 am at Doc's request. Doc reveals a DeLorean DMC-12 which he claims he has modified into a "time machine", but as I will prove to you he actually invented a Ghaldron-Hesthor field-generator.
The car's ability to travel through time/multiverse is powered by nuclear fission. Using plutonium as fuel, 1.21 gigawatts of power is generated into a device Doc calls the "flux capacitor". Doc also explains that the car travels to a programmed date upon reaching 88 mph. To test to make sure his device works, Doc places his dog, Einstein, into the car and uses a remote control to drive the car up to 88 mph, supposedly sending the dog forward in time by one minutre. Now ignoring the fact that Doc is willing to test his experimental, nuclear powered car on his beloved furry companion; this is the first time we see the DeLorean used to travel through "time". In fact, one theory on time travel suggests that it is impossible to travel back to before the time machine was actually made. So theoretically the DeLorean is working perfectly as a time machine.
Do not be fooled however by this correct application of time travel. What you need to understand is that what comes back is not the real Einstein. If we accept the multiverse theory as true, than we live in a reality composed of infinite number of infinite universes. Consider that for a second, Marty's home universe is infinite in size. That means that any divergences between his universe and neighboring universes could exist galaxies away from each other. That means that there is likely an uncalculable number of Earths where everything is happening the same way as it is happening on Marty's Earth. Trillions of Martys and Docs could have sent trillions of Einstiens into another universe and they would think it was time travel.
In reality, the Einstein and the DeLorean that appeared a minute after the original Delorean was activated were from another timeline. This other timeline was so similar, however, that neither Marty, Doc nor Einstean could tell the difference. I realize that you may be thinking that I am overcomplicating things, but keep this in mind as I continue to breakdown the film.
Now back in Marty's reality, Doc is about to make his first trip, but he is interrupted by Libyan terrorists from whom he stole the plutonium from. They proceed to gun him down, while Marty can do nothing but watch. Marty attempts to escape in the DeLorean, but, in the process, reaches the speed of 88 mph and is transported back to November 5, 1955, a date Doc programmed into the DeLorean as an example destination. Marty finds himself without the plutonium needed for the trip back, and the car shuts down, leaving him stuck in 1955. Of course, he is not stuck in his 1955, but in the 1955 of another universe.
In the first minutes following Marty's arrival into this other universe, Marty commits several actions that prove he is not in his own timeline anymore. He crashes into a barn, awakes and is shot at by the family who owns the barn and while fleeing runs out of gas forcing him to ditch the DeLorean, but not before trying to flag down an old couple in a car who fearing that they are in danger of radiation, due to Marty's hazmat suit, flee. As alternate historians, we recognize these as points of divergence and we know that due to the butterfly effect/jonbar hinge these divergences can (and should) cause massive, unpredicatable changes to history, even if the divergences themselves are rather minor changes in the grand scheme of things.
In fact, if Marty really was from the 1985 of this timeline, we should see him changing (or cease to exist) to reflect his own alternate future. We should have seen him act differently, wear different clothes or have a different hair cut. He might even come to look like this:
Heck, he may even start speaking Russian (due to the fact that because Marty stopped the old couple they were in time to run over the guy whose death would eventually lead to the United States losing the Cold War). Yet we do not see these changes. Marty's personality and even his appearance should change due to his interactions in the past, but he continues to exist as he did before he entered the DeLorean. This fact will become more pronounced later in the film.
Back to the story: Marty accidentally meets his father, George, who even as a teenager was bullied by Biff. Marty follows George and finds him in a tree watching a woman (presumably Marty's mom) undress. George falls from the tree and is about to be hit by Lorraine's father's car, but Marty pushes him out of the way and takes the impact. As a result, a teenage Lorraine becomes infatuated with Marty instead of George. Now this is a major point of divergence. From this point on the relationship between his parents is inevitably altered. Yet Marty still does not reflect the changes he is making to reality. Now you might counter by saying that you cannot change the past and all of this was meant to happen and that is why Marty is not turning into a different person right in front of his mother, grandparents, uncles and aunts. If I may jump ahead, however, we know (if you have seen the film) that Marty will arrive back to 1985 and find everything different...so that argument is out the window.
Marty, finding himself in an Oedipul-like nightmare, leaves to find the younger Doc of 1955. Marty convinces Doc that he is from the future (right after Doc has a nervous breakdown) and asks for help returning to 1985. Doc explains that the only available power source capable of generating the required 1.21 gigawatts is a lightning bolt. Marty then shows Doc the "Save the Clock Tower" flyer he had received from 1985, indicating that lightning will strike the courthouse clock tower the following Saturday at 10:04 pm. Doc makes plans to harness the lightning strike to power the DeLorean's flux capacitor.
At this point, the pair discover a complication when observing a fading photograph of Marty with his siblings: Marty has prevented his parents from meeting and has jeopardized his siblings' and his own existence. Now I admit this event makes my argument look weak. How exactly do I explain the vanishing picture? I admit that it is a problem, but is likely an individual timeline will correct itself as travellers from the multiverse interact with it. Essentially as the probability of some object or person from outside the universe actually existing decreases, the timeline will delete it. Now why this deletion does not happen immediately is a mystery. Perhaps the changes being made by Marty have not yet reached the probability limit where the universe will begin correcting itself. Whether this correction happens naturally or is done by an intelligent being is also unknown, but it happens and we have to accept that for the time being.
Back to the story again: Marty attempts to set George up with Lorraine, but she only shows romantic interests in Marty. In order to make his parents fall in love, Marty plans to have George "rescue" Lorraine from Marty's overt sexual advances (remember this is his mom...gross) on the night of the school's Enchantment Under the Sea dance. However, the plan goes awry when a drunk Biff unexpectedly shows up, pulls Marty from the car, and attempts to force himself on Lorraine. Now it is never established whether or not Biff ever raped Lorraine in Marty's original history. Regardless, history has changed even more drastically from Marty's original timeline, yet he continues to act just as if that timeline never changed. Why is he not changing? The logic of time travel states that he should be changing in front of our very eyes and yet he is still the Marty we met from the beginning of the film.
Before things get much farther with Biff and Lorraine, George arrives. Expecting to "rescue" Lorraine from Marty, George finds Biff instead. Biff subjugates George, but George stands up to him for the first time and knocks him out with one punch. A smitten Lorraine (apparently turned on by the near rape and violence) follows George to the dance floor where they kiss for the first time, assuring Marty's existence. Marty celebrates by playing his rendition of Chuck Berry's "Johnny B. Goode", three years before it would be performed. Of course Chuck Berry's cousin would hear it and call Chuck himself so he could listen to his own song. Why Berry did not go insane after hearing this is beyond me.
What is this event telling us? Chuck Berry obviously wrote this song in Marty's timeline, but as we already know, it was in a timeline where Marty did not interfere in his parents' courtship or for that matter play "Johnny B. Goode" in 1955. Yet this movie seems to imply that Berry was not inspired to write his song until a teenager from the future came and played it for him in 1955, the same time OTL Berry wrote the song. So does that mean in Marty's reality Chuck Berry was not inspired to write the song until later? "Johnny B. Goode" is one of the most recognizable rock songs in music history. It being produced later could and probably would have changed the cultural history of the 20th century.
Now I think we all realize that Marty's reality is not our own, but this fact means that his reality is more divergent from our timeline than we realize. It also explains why Huey Lewis (famous musician OTL but apparently a meek civil servant in Marty's reality) rejects Marty's band earlier in the film for being to loud. I think we narrowed a major POD for Marty's universe: because Chuck Berry released "Johnny B. Goode" later than he did in OTL, Huey Lewis was never inspired to go into music.
Still with me? Well back to the story: Marty arrives at the scene of the anticipated clock tower lightning strike where Doc is making the final preparations. Marty attempts to warn Doc of his murder in 1985 in a letter, but Doc indignantly tears up the letter without reading it, for fear he will alter the future. Of course we now realize that is not true, but Doc and Marty have yet to realize it due to the drama they have been through the last week. Things get even worse when the storm disconnects Doc's wiring setup that will capture the lightning, but the two repair the connections just in time for the lightning strike to send Marty and the DeLorean back to 1985...but not Marty's 1985. He has been sent to an alternate timeline.
Even though Marty reset the time machine to arrive before Doc gets shot, Marty still arrives too late to prevent the shooting. Standing by the Lone Pine Mall (remember Marty ran over the pine tree earlier in the film), Marty is helpless to prevent the Libyans from gunning down Doc and later chasing the other Marty into the past (we assume who knows what time this alternate Doc set in the DeLorean). Marty cries over Doc's dead body, but surprise, Doc reveals he had taped the letter back together and was wearing a bulletproof vest...thus proving that Doc has a "do as I say, not as I do" mentality in his relationship with Marty and others.
Doc drops Marty off at home and leaves in the time machine for the future. Marty awakens the next morning to find his home and family significantly improved and happier. Lorraine is physically fit, George has become a self-confident and successful science fiction author, Marty's brother Dave is now a businessman, and his sister Linda no longer has trouble finding boyfriends. Most notably, George and Lorraine now have the close relationship they never had, while Biff has become an auto detailer/washer and is now very deferential towards George (and no one mentions that this sex offendor once tried to rape Lorraine).
The above paragraph is very important to my theory. This version of Marty's family are the exact opposites to the version of Marty's family we were first introduced to. Consider what it would be like to be raised by both families, do you think you would be the same person in each situtation? The Marty we know has his personality and memories due to his disfunctional family. Yet the Marty that this new and improved McFly family loved and raised would have a completely different personality and memories than the original Marty. Why does our Marty not reflect this? In fact he faints when he realizes how different everything is. His family reacts with worry and concern, which are probably alien concepts to this original Marty.
The alternate McFly family already thought something was wrong with Marty, and if they (including this reality's version of Doc whom would have befriended a very different Marty) spent more time with Marty they would have eventually realized that he was not their son. He might look like him and talk like him, but he would not have shared the same experiences and lack knowledge of important moments in their lives. It is probable that Marty would have admitted that he time travelled back to 1955 and changed how his parents fell in love. If given the chance, George (being a successful science fiction author who may have stumbled on some alternate history tomes during his career) would have speculated that it was impossible for him to have been a time traveller or else Marty would have changed as well to reflect the changes he was making to the time stream. Perhaps it would be this alternate George who would express the theory I am writing now on this blog.
This epiphany, however, never comes about. Just as Marty reunites with his girlfriend Jennifer, Doc arrives, insisting that they accompany him to the future to sort out a problem with their children. With Doc at the wheel, Marty and Jennifer enter the upgraded DeLorean, now a flying hovercar powered by nuclear fusion, and they go back to the future.
So the movie ends and we are left with the realization that this does not make sense as a time travel film. I am here to tell you, again, that this had nothing to do with time travel. Instead it was all about multiverse travel. We saw evidence of five different timelines in action:
1) Earth 0: The timeline where the dog Einstein was sent from during Doc and Marty's original test of the DeLorean.
2) Earth 1: The timeline of the original Marty, set in 1985. Here the McFlys are a disfunctional family, Chuck Berry released his song "Johnny B. Goode" later than OTL and Huey Lewis never became a musician. My guess is that after Marty disappears and Doc is found dead, the McFly family disentegrates over the pain of Marty's loss.
3) Earth 2: The timeline where the original Marty arrived in 1955. Here he altered the events of his parent's courtship and inspired Berry to release his famous song earlier and ensured that Lewis would have a career in music. Exactly how this timeline turned out by 1985 is unknown, but my guess is that Biff would end up in jail for his attempted rape of Lorraine.
4) Earth 3: The timeline Marty arrived in when he thought he was returning to 1985. Here the McFly family is successful and supportive of each other and also keep Biff around as a servant. This is probably not a timeline based on the changes Marty made to Earth 2, as it is unlikely any sane person would allow a rapist to be around their family. It is likely that this was the closest analog that the DeLorean could reach based on the timeline they were leaving. Why the DeLorean does not go to a random timeline is unknown, but the movies seem to suggest there is only so many places it can or is allowed to reach.
5) Earth 4: The timeline that future Doc arrives from to take Marty and Jennifer back on another trip...eventually reaching Earth 5.
So there you have it. A saner (for my standards at least) explanation of what exactly happened to Marty McFly when he got into Doc's DeLorean. I will breakdown the next two films in the coming weeks, so stay tuned for more examples about why the multiverse theory allows for the illusion of time travel. I will also be posting a review of After America by John Birmingham later this week.