A popular Fantastic Four fan theory could explain why the Marvel universe exists on a sliding timeline. As characters age and de-age incongruently with real time and history always rushes to catch up with the present, it's possible that Franklin Richard's incredible power could be the source of one of Marvel's oldest and strangest phenomenons.

What is Marvel's Sliding Timeline?

History of the Marvel Universe #3

In essence, the "sliding timeline" refers to how the progression of time in the Marvel Universe is not what it's like in the real world. Either time passes exceptionally slow or, every number of years, Marvel picks a new year as the official "start" of their timeline (hence, the moniker "sliding"). That is why the Fantastic Four, for example, are still protecting the planet nearly 60 years after their debut.

In doing this, characters and stories are altered or changed to fit the narrative and/or to keep the heroes relatively the same age. This includes the erasure of cultural trends or historical events originally referenced in stories or characters' origins. For example, when Frank Castle, aka the Punisher, first debuted in the Marvel Universe, it was stated that he was a veteran of the Vietnam War. However, in the most recent retelling of Marvel Universe history, it has been established that Frank is now the veteran of a fictional war in Southeast Asia, the Sin-Cong conflict. Likewise, Reed Richards and Ben Grimm, who were originally said to be veterans of World War II, were also retconned to have served in the fictional war. There are numerous other examples.

As a reader, the explanation is simple: Marvel wants to keep its characters young so it shifts their origins as time goes on. However, a popular fan theory from The Fantastic Four: The Great American Novel blog has for years posited that there is an in-universe explanation: Franklin Richards.

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The Source of Franklin's Powers

Franklin Richards using his cosmic abilities, while Doctor Doom watches him from behind.

As Fantastic Four fans know, Franklin Richards is the firstborn child of Reed Richards and Sue Storm. His debut in 1968 was notable because it was one of the first times two superheroes married and had a child. More notably, however, Franklin is also a powerful Mutant (or non-Mutant if recent events of the comics are to be believed) who can alter reality and create universes. Franklin has used his powers extensively in the past and, in the last few years, has even embarked on creating an entire multiverse. He is, in essence, a god. And, if this theory is to be believed, he is the reason why Marvel's history is constantly being retconned and changed to maintain the characters' youth.

While the longtime explanation for his abilities was that he was a mutant, recent events of the Fantastic Four series have pointed to the possibility that Franklin isn't one after all. The theory points to an alternate origin for Franklin's powers -- one that has ties to his origin.

In Fantastic Four Annual #6, by Stan Lee and Jack Kirby, to save a pregnant Sue from radiation poisoning, Reed, Johnny and Ben gather Anti-Matter from the Negative Zone. In the end, Reed used the energy from Annihilus's Cosmic Control Rod to save Sue and their unborn son. The Cosmic Control Rod is known for allowing its wielder to manipulate matter and energy and slow down their aging process. In other words, the Cosmic Control Rod helps grant immortality, something that Annihilus himself states. Therefore, in doing so, it's possible that Reed may have unwittingly passed these onto his newborn son, making him nigh immortal.

If the theory is correct, Franklin isn't just prolonging his own life, he's granting everyone else in the Marvel Universe immortality as well.

As a strong piece of circumstantial evidence, consider that before 1968 -- the year that Franklin debuted -- characters in the Marvel Universe more or less aged in real-time. For example, Peter Parker graduated from high school, started college, and made the first forays into young adulthood. Other heroes also experienced normal aging as well. However, it was around the time that Franklin debuted, post-1968, that heroes became somewhat frozen in their then-current age.

In the case of Peter, he became a perpetual young adult and hasn't progressed past his late 20s or early 30s in over 50 years. This is also the case with heroes who were adults at the dawn of the modern Marvel Universe but who seemingly have not aged much since, even though Peter himself has, including people like Tony Stark or the Fantastic Four themselves.

Furthermore, Franklin may not even be aware he is using his reality-altering abilities. In fact, this has even been known to happen before, in very big ways that have also altered the lives of Marvel's heroes. In the Heroes Reborn event, for example, Franklin created an entire pocket universe, placed the Marvel heroes into that universe, and rebooted their lives, without ever being fully aware he was doing it.

Recent events have cast doubt on the origins of Franklin's powers. Despite years of being told he was a Mutant, there's now a real possibility that he is not. This could mean that the origin of Franklin's powers does indeed lie with the Cosmic Control Rod and Annihilus.

However, not only is the source of Franklin's powers in doubt, but he's also currently losing them. Franklin's powers are dissipating so fast that he's had to actively conserve them. If the theory is true, it could explain how Frankin has now aged several years, instead of remaining the child he was for decades. And, again, if this theory is true, what does it mean for the rest of the Marvel Universe? Will Peter Parker suddenly go from being a man in his late 20s to one in his late 70s? Will Reed and Sue suddenly become octogenarians or perhaps even suddenly pass away?

If so, then things might be interesting in the near future. But, again, this is just a theory. And that's half of the fun.

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