In this nonsensical philosophical rambling, I’m going to use quantum mechanics and the existence of parallel universes to justify that I am the only thing that “really” exists in the universe.

Background

Quantum Mechanics

Big brain physicists have proven we live in a profoundly bizarre reality with a handful of theories backed by experiments:

1. You can’t know BOTH where something is (position) and how fast it’s going (momentum). This is Heisenberg uncertainty principle.

The more carefully one tries to measure position, the more disruption there is to the system, resulting in changes in momentum.

2. Light acts as BOTH a wave and a particle, depending on whether or not it’s being “observed.” This is “wave-particle duality” and is confirmed by double-slit experiment.

It’s as if they knew they were being spied on and decided not to be caught in the act of performing weird quantum shenanigans.

3. The speed of light is only constant in a particular reference frame: This is Einstein’s theory of special relativity.

Simultaneous events as seen by one observer could occur at different times from the perspective of another.

This highlights two foundational concepts: the very act of observing something changes it, and all conscious observers exist in their own reference frame.

Remember these concepts and stick with me: we’ll use them shortly to prove that I’m the only thing that exists.

The Multiverse

The idea that there are many parallel universes out there has been explored at length by popular culture (e.g., Rick and Morty) and in science itself as part of string theory:

String theory suggests that our universe is one of many parallel universes that float in a higher-dimensional space. String theory also suggests that these universes can interact with each other.

More recently, though, we’ve found experimental evidence that the multiverse might be the only valid explanation for absurdly complicated computations performed by quantum computers:

Willow’s performance on this benchmark is astonishing: It performed a computation in under five minutes that would take one of today’s fastest supercomputers 10 septillion years. This mind-boggling number exceeds known timescales in physics and vastly exceeds the age of the universe. It lends credence to the notion that quantum computation occurs in many parallel universes, in line with the idea that we live in a multiverse.

— Google Blog

Thus we’ll assume they exist.

Solipsism

I think, therefore I am.

While today this sounds like something your older cousin would say after selling your teenage self some crappy weed, it was actually a profound thought by Descartes at the time.

To elaborate, he states that the very act of thinking proves one’s existence: this is solipsism, which argues that the only certainty is one’s own mind and thoughts. The external world, other minds, even reality itself, can be doubted or simulated, but I can be sure that I exist somewhere (even if that may be in a vat somewhere à la The Matrix) because I can think.

Infinite Butterflies

Every action, thought, and even observation you make fundamentally alters your entire universe (per observation (1) in the QM section, above). There’s no such thing as passivity:¹ seeing something happen fundamentally changes both you (neurons) and the situation itself (measurement). We’ll go so far as to claim that your observation splits your universe² into many others: you remain in the one that opened Schrödinger’s box and observed the cat, while new ones form for the other possibilities.

Since you are the only reliable observer in the universe, and your observations irreversibly modify the universe, your subjective experience is YOUR universe. This, of course, extends to interactions with other people. You only experience the version of them you perceive and observe. Even though they continue to have their own experiences, their reality exists through their eyes and yours through yours.

Let’s get even weirder: since time is relative to the observer (per (3), above), then everyone sees everything happen at a different time. This in and of itself demonstrates that we’re all living in our own little worlds. Add in the fact that everything I observe changes reality in MY frame of reference just enhances the notion that it’s MY universe.

Main Character “Syndrome”

Since you are THE observer in your own universe, you are its main character. While everyone else may be “unplayable,” they instead become a reflection of your own character: their outcomes and actions are entirely shaped by your actions. The butterflies are in full effect here: your interactions with others may ultimately circle back to you.

This isn’t to say, of course, that those people aren’t real. They are very real, but their own actions define their own path in their own universe. Your actions define their path in YOUR universe. As Descartes said, nothing is real besides you.

The purpose of their presence is to highlight your choices: like a complicated video game with branching decisions, the choices you make shift you (and everyone in your game) into a new universe with a new ending.

Implications

With these heavy thoughts in play, we have to consider the implications. If every step through your life splits you off down an unique, irreversible path, then the universe itself exists to test you. This can be liberating in a way: the world is a sandbox for you to play in. But it’s also daunting: every action you take matters on a deeply existential level because you are your universe’s only real participant.

What happens at the end of the game? Does it fade to black and show you your stats? Do you get to watch all of the other paths you could’ve taken? Is there an Almighty to judge your final score?

Conclusion

These musings beg the question: how will I define my reality next?

One thing is clear, at least: you reading this article doesn’t really matter to me, because it’s my universe.³ And yeah, maybe it makes no sense, but my universe isn’t optimized for your reality engine. Regardless, it irreversibly affected you.

Thanks for observing!