For the past decade, Netflix’s hit show “Stranger Things” has captivated viewers hooked to the relationships, characters and most importantly, the interdimensional sci-fi background of the narrative. In an epic three-part finale that aired at the end of 2025, the questions, plot holes and twists finally came together. While the idea of Demogorgons and flesh-made mind-flaying monsters may be a stretch from reality, the foundation of physics and parallel universe theories are actually grounded in real scientific thought.
Quantum mechanics governs much of the show, including the presence of the Upside Down and eventually Dimension X, or The Abyss. The Upside Down is an alternate realm that the characters uncover throughout the show – identical to their town but filled with monsters, toxic air and deadly vines. In the fifth season, it is revealed that the Upside Down is in fact a bridge to another dimension entirely, which the characters refer to as The Abyss. Quantum rules have baffled scientists and theorists for years, as they disobey all means of logic by telling us that a particle can be in two places at once. If you have heard of the famous Schrödinger equation, a wave equation that predicts the probability of a particle being in a specific place at a specific time, then you know that physicist Erwin Schrödinger had an influential role in understanding quantum mechanics. Schrödinger was uncomfortable with the idea of the wave function collapse – the notion that a quantum system suddenly changes state upon measurement – and instead hoped that the wave function would evolve smoothly according to Schrödinger’s equation, without being altered by observation. He illustrated the problem with this idea through Schrödinger’s cat experiment, which highlights the paradox that, if a system can exist in multiple possible states at the same time, a cat could be both alive and dead until observed. Later interpretations propose that all these outcomes happen simultaneously in separate, non-interacting versions of reality.
Years later, physicist Hugh Everett proposed the “many-worlds theory,” which introduced the concept of the universe splitting into different versions of itself. In an effort to avoid confusion about the metaphysics of our universe: It is as if every quantum choice rips apart our world into opposing dimensions of itself. Sound familiar?
The first four seasons of “Stranger Things” operated on this idea that there was an identical, opposite universe, or “Upside Down,” mirroring Hawkins, Indiana. The actual science behind alternative universes and multiple simultaneous outcomes of life and death almost makes the show more terrifying and unsettling — the show presents the idea that something similar could be brewing in real life. Imagining a dimension where everything is the same, yet different, and the universe splits at every quantum state, makes one question: what is truly real? In reality, however, quantum physics does not allow the possibility for anything in our dimension to reach another one, much less rip open portals and go on a casual stroll. It’s safe to say that we do not need to worry about the Upside Down.
In the fifth and final season, the characters unearth the truth about wormholes and the bridge between their world and The Abyss. This new dimension completely changes everything previously known about the Upside Down. In “Stranger Things,” the universe is a wormhole, a theory based on physicist Albert Einstein’s general theory of relativity. This concept states that the universe consists of a space-time continuum and has the ability to form a bridge connecting two distant worlds — an Einstein-Rosen bridge. It is revealed that a large mass of exotic matter with negative energy existed in the Upside Down’s Hawkins Lab. This exotic matter stabilized the Upside Down, acting as a bridge between dimensions. Eventually, the characters plan to blow up the exotic matter, therefore crumbling the bridge and destroying the Upside Down, sealing their dimension indefinitely.
Foundations in science and physics exist at the very core of this hit show. The plot intricacies, shocking twists and grand reveals would be meaningless if not backed by very real concepts. Perhaps, this is part of the reason why the show can be so terrifying. It reminds us how little we know about our universe and the intangible laws that govern the matter surrounding us. Particles existing in two places at the same time, worlds colliding and splitting instantaneously and bridges connecting dimensions is not all fiction, but are backed by the theories and ideas that physicists have pondered upon and studied for centuries.
Our universe may be “stranger” than we care to admit. That is, if there is only one universe…
