What Happened at the End of Avengers: Endgame with Captain America’s Time Travel?

A pivotal moment in Avengers: Endgame revolves around Captain America's (Steve Rogers) decision to travel back in time to reunite with Peggy Carter, his love interest. This choice has sparked considerable debate among fans and critics, leading to two primary interpretations of the events. Let's analyze both perspectives and delve into the implications of each.

Option 1: Maintaining the Prime Timeline

According to this theory, Steve returned to the past but did not change the course of the primary timeline as we know it. He married Sharon Carter, kept a low profile, and allowed many terrible events to unfold, including Hydra's control of SHIELD and Bucky's brainwashing. The main issue with this theory is that it raises ethical questions. Would Steve really ignore the suffering of his friends and darkest days of history for the sake of maintaining the timeline's continuity?

HYDRA grew inside of SHIELD, Bucky being brainwashed, the assassination of the Starks... In a timeline where Steve chose to live a normal life as a marine in the future, would the course of the MCU as we know it really remain the same without intervention?

Option 2: Creating a New Timeline

Alternatively, the theory of creating a new timeline suggests that Steve and Peggy's time travel resulted in a spontaneous branching of the timeline. In this new timeline, Steve was free to rescue Bucky, prevent Hydra's rise, and make the necessary sacrifices to change the course of events. However, there are several inconsistencies in this theory. For instance, when Steve returned, he appeared on a bench in the distance, far from the time travel device. This raises questions about how he managed to jump back into our timeline without being present in the correct location.

How could Steve travel to the past and create a new timeline if he didn’t reappear on the time travel stand like the other characters? This puzzle adds weight to the theory that there's a separate continuity at play.

Belief in Separate Timeline

Considering the extensive efforts of the Avengers to return the Infinity Stones to their exact locations, it's plausible that Steve's journey aligns with a separate timeline parallel to the prime one. This theory suggests that Steve could fit into a continuity blind spot, where his actions do not interfere with the established narrative.

In a quantum observation situation, if Steve's reality never intersects with the prime timeline's observer (i.e., a version of himself or another character), his presence could remain undetected. This is akin to a reverse Back to the Future scenario, where one cannot change their prime timeline's present but can alter the past leading to their present without contradicting the prime timeline's established events.

It's Back to the Future in reverse: Steve cannot taint his own past, but he can modify the timeline that led to his present so long as he does not cross paths with his prime timeline’s present. His actions fit a causality loop, allowing the timeline to loop back onto itself just like it did when the Infinity Stones were placed.

This interpretation aligns with the broader continuity of the Marvel Cinematic Universe (MCU), where timelines are fluid and interconnected. Steve Rogers, being a central character, can navigate through these complex timelines with minimal interference, ensuring that his love and actions remain a catalyst for change in the broader narrative.

Conclusion

The events of Avengers: Endgame involving Captain America’s time travel are intricate and multifaceted. Whether maintaining the prime timeline or creating a new one, the outcome of Steve’s journey remains a testament to the interconnected and sometimes fluid nature of the MCU. Fans and critics alike continue to ponder the implications of these actions, enriching discussions and theories about the intricacies of this grand cinematic universe.