Star Trek has created a great many talking points over its 50+ years, both positive and negative. One of the most puzzling points is the fact that Guinan can somehow recognize Jean-Luc Picard in the Nexus, even though she was pulled from it some 78 years prior. Many believe this to be a plot hole or writer error. But there is a plausible explanation, albeit a bit of a brain-bender, and partly theoretical.
The trick to understanding this issue is to be found in a little concept known to Physicists as Quantum Entanglement. This is a concept that even the most learned of us has a little trouble reconciling.
Theories suggest, unlike Captains Picard and Kirk, Guinan was ripped from the Nexus, causing a piece or echo of her to remain in the Nexus. Since the Nexus exists outside of conventional reality, it is in a way connected to every point in time and space.
To explain further, let’s have a look at a brief explanation of the Quantum Entanglement Theory.
Quantum entanglement is a physical phenomenon that occurs when pairs or groups of particles are generated, interact, or share spatial proximity in ways such that the quantum state of each particle cannot be described independently of the state of the others, even when the particles are separated by a large distance. – Quantum Entanglement explained for the layman.
Using the Quantum Entanglement theory, we assume that regardless of the distance between them, the echo of Guinan and her physical self are connected. El Aurians have been known to display varied ranges of empathic abilities. This would allow Guinan to be aware of her ‘other self’ to some degree, and vice versa. Just as she was aware that the timeline had been altered during The Next Generation episode, “Yesterday’s Enterprise”.
With Veridian III destroyed, the Enterprise and its crew were lost, along with Guinan.
In the aftermath, her echo, having felt her ‘other self’s” passing, then became aware of Picard’s presence in the Nexus. At the moment of her death, all Guinan’s memories and emotions would have been lost too. Through her connection, it can be hypothesized that these are shared with her Nexus counterpart as well. There is no other way that Guinan would have such intimate knowledge of Picard to recognize him or find her way into his Nexus dream.
What happened to Guinan’s Nexus counterpart following the Veridian III disaster was averted, remains a thing of mystery. Whether she is still in The Nexus or ceased to exist, we may never know. Hopefully we will see her again someday.