Blog Post

The Real Science Behind the Multiverse and Parallel Realities

December 29, 2024

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What if every choice you made split your life into countless parallel realities, creating infinite versions of you living entirely different lives?

This mind-bending concept, known as the multiverse, is increasingly being employed as a plot device in popular shows and movies, where parallel or alternate universes intersect or become interwoven.

In the Marvel Cinematic Universe, Dr. Strange navigates between disparate realities to prevent the Scarlet Witch from destabilizing the multiverse with dark magic as she searches for alternate versions of her children. In Rick and Morty the duo accidentally ruins Earth in their primary reality. To escape the consequences, they flee to another, replacing versions of themselves who have just died. In the film Everything Everywhere All at Once, Evelyn discovers infinite versions of herself in parallel universes, each living a different life shaped by alternate choices she made.

My novel, The Subtle Cause, is also heavily predicated on the multiverse concept. But more than just using the multiverse as a creative backdrop, The Subtle Cause dives deep into the principles of quantum mechanics that portend its existence while exploring the philosophical questions it raises about choice and randomness.

This might surprise most people, who likely assume that the multiverse concept is pure fiction, or pseudoscientific conjecture at best—an imaginative narrative device to provide entertaining fodder for sci-fi thrillers. But the idea is scientifically grounded. Some of the world’s leading quantum and theoretical physicists are proponents, insisting that it offers the best framework to explain many of the most elusive mysteries of our universe.

In this article, we will explore the scientific principles and justifications behind the multiverse, and how it is even more mind-blowing than popular imagination makes it out to be. If anything, it is being understated and undersold.

To understand the multiverse, we first need a clear definition.

What Exactly Is the Multiverse?

Even to define the multiverse is complicated because there are many ways of thinking about it. I have found Max Tegmark’s Four Levels of the Multiverse to be the best conceptualization:

Level I: Distant regions of space that are beyond our current observational capabilities—an extension of our own universe where infinite space gives rise to infinite configurations which in turn give rise to infinite possibilities. If cosmological inflation extends space infinitely, then every variation will be realized, since configurations inevitably repeat themselves. This means that there is a copy of you that made a different decision at every potential datapoint.

Level II: Distant regions of space that are forever unobservable to us because space keeps inflating to keep them out of reach of the speed of light. Because different pockets of space have varying densities and compositions, these pockets develop unique cosmological constants as inflation continues to expand space itself, resulting in entirely different types of matter, chemistry, and even life.

Level III: This is based on the Many Worlds Interpretation (MWI) of quantum mechanics, introduced by physicist Hugh Everett in 1957. It stems from the idea that every quantum event leads to a branching of the universe, where all possible outcomes occur across the infinite array of separate, parallel realities.

The Level III multiverse will be the focus of this article since it is the version that tends to inspire sci-fi plots, The Subtle Cause included. MWI is the most philosophically compelling because our alternate versions are not just statistical reproductions in contiguous space. Instead, they are distinct versions of ourselves—each living out a different possible life. The connection to these variations of ourselves is more personal because we were at one time literally one and the same. It also happens to be the most scientifically interesting conceptualization of the multiverse, since it is the version most steeped in quantum mechanical principles.

By the way, I did mention there were four types. Level IV is merely an ensemble of the first three, which is hard to argue with since there is a strong case to be made that all three apply.

The “Everettian” Many-Worlds Interpretation (MWI)

Essentially, MWI seeks to take the mathematical foundations of quantum mechanics at face value. This stance is justifiable given that quantum mechanics produces predictions that are more accurate than any other branch of science. Even its most counterintuitive implications, like quantum entanglement, quantum tunneling and wave-particle duality, have been consistently validated in experiments and transformational technologies that power the modern world.

MWI aims to resolve one of the most perplexing aspects of quantum mechanics, which is the measurement problem. The measurement problem refers to the enigma of how and why a quantum system’s many possible states, as described by its wavefunction, appears to arbitrarily collapse to a single, definite outcome when observed or measured. The closely related observer effect suggests that the act of measurement or observation, whether by a human or instrument, fundamentally alters the state of the quantum system by interacting with it.

To dispel some of the mystery of this, it is important to understand what is meant by “wavefunction”.

What is the Wavefunction?

Wavefunction refers to a complex mathematical function that encodes all the information and degrees of freedom describing a quantum object or system, including every possible state and the probability of being found in each of these states.

Metaphorically, we can think of the wavefunction as a map that shows all the possible places an electron could be, with probabilities acting like 'heat spots' indicating where it is most likely to be found.

Every quantum object or quantum system has its own wavefunction. This could be a single particle such as an electron or photon, or a composite system such as two or more entangled particles. In theory, even macroscopic objects such as a cat—or the entire universe, including every branch or alternate version—could be described by a unified wavefunction succinct enough to fit on a t-shirt.

A quantum object or system described by a wavefunction exists in a state of superposition, which is another fundamental feature of quantum mechanics. Every interpretation of quantum mechanics acknowledges that before a measurement or observation, quantum objects and systems appear to reside in a multiplicity of potential states simultaneously. This applies to variables such as position, momentum, spin, energy, polarization, angular momentum, phase, and potentially many others, depending on the object.

To summarize, the wavefunction represents all the possible states of a quantum object or system, and superposition is the state where the reality appears to be a direct manifestation of the mathematical description.

For example, the wavefunction might tell us all the potential locations an electron could inhabit, which can be ascertained by applying the Schrodinger Equation to the wavefunction. If we take the math literally, then the electron inhabits multiple positions at a given time. Clever experimental setups that enable us to observe the electron indirectly, such as the double-slit experiment, prove that this is indeed the case. But then if we observe the electron directly, it assumes a position that is more precise, although not perfectly precise (see Heisenberg Uncertainty Principle).

One of the earliest attempts to explain this effect remains the conventional approach to this day. Known as the Copenhagen Interpretation, it suggests that the quantum object or system exists in a superposition of states until the wavefunction spontaneously collapses upon measurement. At this point, the object or system “chooses” a single, defined state.

This has raised a number of vexing questions: What constitutes a measurement? Is consciousness required, and if so, how is it defined exactly? Why does pure randomness seem to play a role in observed outcomes? What mechanism is ultimately “choosing” if higher probability outcomes are not consistently occurring over lower probability outcomes?

Since its formulation nearly a century ago, the Copenhagen Interpretation has left these questions unanswered. Furthermore, there is nothing in the mathematical framework to suggest that measurement, observation, consciousness, or mysterious randomness should impact quantum objects or systems at all.

Hugh Everett rightly noted that this interpretation attributes an undeserved and unexplainable role to measurement and observation in the process. The mathematical equations that govern quantum mechanics do not imply that there is a mechanism which should cause a superposition of possibilities to spontaneously narrow to a single value only, effectively destroying all others.

Hugh Everett’s epiphany was to take seriously the wavefunction and its formulism. He hypothesized that the wavefunction does not collapse but instead continues to exist in all its possible states. What we perceive as "collapse" is simply the appearance of a single outcome from a limited perspective. By treating the wavefunction as a universal and literal description of reality, we are forced to grapple with the implications of its multitudinous nature.

All is Quantum

Everything we observe in the universe—from the smallest particle to the largest galaxy and to the laws that govern them—is built on the strange and counterintuitive principles of quantum mechanics which seem to contradict those we observe at the larger scales familiar and comfortable to us. We know this with certainty because our most advanced technologies, like semiconductors and lasers, rely on these quantum principles, demonstrating their undeniable connection to reality.

At the heart of quantum mechanics is the wavefunction, governed by the Schrödinger equation, which forms the foundation of everything. According to its calculations, the universe is fundamentally probabilistic, and experiments consistently confirm this. But there is not a mechanism by which probabilities terminate. Even if a single probability is observed by measurement, all probabilities persist indefinitely in Hilbert Space, which is an infinite-dimensional mathematical framework that contains all possible quantum states of a system.

If we take this literally, it means that every quantum outcome branches into its own parallel universe, governed by the same fundamental laws, and that this process continues endlessly. Superposition does not end at measurement or observation. Instead, it extends into a conceptual, yet indelible, global structure that immortalizes all possible states. This is the “Multiverse” at its very essence.

If all is quantum, then all is mathematical. But how does that work?

Any system in a state of superposition has, by definition, a shared wavefunction. According to the branch of mathematics known as wave mechanics, this means its real and imaginary components combine to create interference patterns, represented by waveforms superposed over one another.

Wave mechanics are widely used in quantum mechanics because they provide an elegant and compact framework for describing and predicting quantum states. Unlike matrix mechanics, which rely on representing quantum systems through arrays of equations, wave mechanics offer a holistic and manageable way to describe a system's probabilities and dynamics.

In the case of an electron, the amplitude of the waveform corresponds to the probability density of finding it in a particular location when measured. The frequency reflects its intrinsic energy, encompassing both potential and kinetic components. The wavelength is directly related to the electron’s momentum, or velocity. Each waveform represents a potential quantum state consisting of combinations of all these variables and others, including spin state and angular momentum.

The phase of each waveform determines how they are aligned, which relates to interference behavior. Constructive interference (phase coherence) occurs when wave peaks align, amplifying their amplitude, while destructive interference occurs when peaks and troughs cancel each other out, reducing or nullifying the amplitude. Constructive interference corresponds to regions of higher probability density, while destructive interference results in regions of zero probability density.

As it relates to an electron’s position, regions of constructive interference represent locations where the electron is most likely to be observed, while regions of destructive interference indicate where the electron cannot be observed. This phenomenon is reflected in the electron orbitals around an atomic nucleus. The solutions to the Schrödinger equation define discrete orbitals that the electron can occupy, with no probability of existing in the spaces between. When an electron gains or loses a certain amount of energy, it undergoes what we have coined a “quantum jump” to suddenly appear in another orbital without traversing the intermediate space. It is yet another example of pure mathematics superseding our human intuition, no matter how bizarre it strikes us.

It would be like having a fundamental equation that specifies: “One Human + One Banana = Human + Banana at the Equator.” According to this hypothetical rule, if a human touched a banana, they would instantly and mysteriously appear at a random location along the equator, regardless of where they started. Although this analogy is deliberately whimsical, it highlights the counterintuitive nature of certain quantum phenomena. Just as this imaginary rule might seem to override classical notions of space and motion, the Schrödinger Equation governs quantum systems in ways that defy our intuition. While it doesn't violate classical laws, it operates within a framework that redefines our understanding of concepts like location, motion, and causality, challenging the assumptions we typically hold as foundational and absolute.

The Schrödinger Equation

The Schrödinger Equation governs the evolution of the quantum wavefunction. It is a Partial Differential Equation (PDE), meaning it involves multiple independent but interrelated variables. This is true in even relatively simple situations, such as predicting an electron’s position. When applied to the wavefunction, this equation doesn't "terminate" or collapse to a singular solution or state when interacting with its environment, but continuously evolves over time. Each possible state influences the wavefunction and the cloud of possibilities it represents, leading to further evolution in accordance with the same mathematical principles. This process is influenced by factors both intrinsic and external. Intrinsic factors include position, momentum, spin, polarization, energy, etc., all of which are inherently probabilistic and can change spontaneously. External factors include magnetic fields, ambient temperature and radiation.

And this is just for a simple quantum system. If we extend this concept to an entire universe, or even multiple universes (as in the Many Worlds Interpretation), the complexity becomes staggering.

But this never-ending state of superposition does not reconcile with our direct experience. Our tendency is to trust in what our senses are telling us, while dismissing the oddities of quantum mechanics as something too cryptic to be properly understood. Certainly, as some vehemently insist, it is not something to be taken literally!

But we’ve been down this road many times before, where the math tells us that the microscopic world is behaving in some counterintuitive way, and we casually wave it off as something not to be believed. But then these counterintuitive concepts eventually prove to be correct after exhaustive testing is performed and new technologies are developed, reinforcing the fact that quantum mechanics is the most accurate description of the microscopic world, consistently outclassing every other area of science in terms of predictive power.

The list of examples is long: quantum tunneling, superposition, entanglement, wave-particle duality, Heisenberg’s Uncertainty Principle, and the Pauli Exclusion Principle. These seemingly bizarre and implausible phenomena have given us MRI’s, lasers, GPS, and many other technologies vital to the modern world.

So, if math is telling us that the wavefunction maintains all its probabilities, each one of them continuing to evolve in an ever-proliferating web of possible universes, past experience tells us that we should take it very seriously. But why do we experience only a single, well-defined thread through this eternally expansive web?

The answer is decoherence.

The Decoherence Contagion

Decoherence occurs when a quantum particle or system in a state of superposition interacts or exchanges information with an external environment. In doing so, a version of it becomes entangled to that environment (a.k.a. a branch in the multiverse). Other versions of this same quantum particle or system continue to evolve with other versions of the external environment in other branches of the universe or parallel realities. This splitting or branching happens constantly, at every point in space and every moment in time. The number of branches is incomprehensibly vast, evolving continuously as the universe unfolds. What we think of as the one, well-defined reality is actually just one contiguous web of information being continually exchanged out of an infinite many separate, contiguous webs. A contiguous web in this context can be thought of as an individual, continuous branch, or a self-contained sequence of events within the multiverse. Strictly speaking, they are large-scale, composite mathematical structures. A self-aware substructure (i.e. sentient lifeform) within this structure would think of it as the observable universe.

But the question is, what constitutes an exchange of information?

Even a single photon can register information about a quantum particle or system, locking an aspect of it into the contiguous web to which it belongs. But there will still be an aspect of this quantum object that remains in a state of superposition, exploring all its other potentialities. Superposition is its true nature though, and from a global perspective, it eternally remains in this state.

From the perspective of the observable universe to which an aspect of it “decoheres”, its wavefunction appears to collapse into a single, narrowly defined and randomly chosen state where it is no longer in superposition. In reality, the quantum object does not just decohere to a single observable universe, but to all possible variations of a given observable universe at a given juncture where it exchanged information. For every possible state the quantum object could inhabit (e.g. position, momentum, spin, polarization, energy level, etc.), it mathematically necessitates a splitting of a universe into separate, noncommunicable branches to accommodate each.

Spacetime is beholden to the wavefunction, not the other way around.

In which case, there is an aspect of the same quantum object that is decohered to every possible variation of the universe and an aspect where it remains in a state of superposition of every possible state—not decohered to any single, narrowly defined universe.

For this reason, we must think of “superposition” as relational in nature. A quantum object is not objectively and universally in a state of superposition or decohered. Instead, the degree to which it is or is not in a state of superposition is based on a particular perspective.

It is not the “observable universes” that are fundamentally real, but rather the virtual superposition of infinite possibilities that animate them to life—represented by inherently mathematical concepts.

And it is by the very idea of this mathematical function (the theorized “universal wavefunction”)—somehow manifested from within an interminable void—that every potential universe at every stage in its evolution simply “exists”, and therefore every version of “you” at every point in conceptual time simply “exists”. The sensation of evolving in time is simply a means by which something so unfathomably vast and manifold can be experienced.

But quantum processes are not time dependent since spacetime emerges from the virtual operations of their quantum functions, and not the other way around. The universal wavefunction, by its very conception, portends every possible state of every possible universe and thus, every possible sequence of events. As the self-aware substructures arising from the illusory, dimensional construct which is spacetime, we can only think about it and experience it in a time-evolution way. This is why we apply the terminology of “branching” to every possible variation of the contiguous threads that weave their way through the endlessly proliferous fabric of all that is possible. It is because our minds are wired to attribute precisely defined “causes” to every event.

What precipitates branching in the multiverse?

In other words, what constitutes a valid or allowed variation of a given state? Imagine that you can freeze time right now as you are reading this sentence as part of a Laplace’s Demon-like thought exercise. Your immediate state is intricately connected to your immediate environment which in turn is connected to the entirety of the universe through a contiguous exchange of information and interaction. All that is hypothetically frozen comprises a single, unified state, which we’ll call the “Right Now Slice”. The “Right Now Slice” refers to a hypothetical snapshot of the universe frozen at a single moment in time, capturing all its properties and relations across every constituent part. But this is just a single slice in an endless sequence—each only minutely varied from the one immediately preceding (past) and following (future).

*Note: For the sake of this thought experiment, ignore the fact that there is no such thing as a universal clock, because simultaneity is not a shared fabric across the cosmos. From a global, omniscient perspective, the threads of causal connection fray over distance. The farther apart two locations are, the more their timelines diverge into ambiguity, until the very notion of “when” one thing happened relative to another becomes not only undefined, but fundamentally unknowable.

As we’ve established, everything is quantum at its most fundamental level. In which case, each of these slices is an elaborate quantum state unto itself. This means the next slice in the sequence is probabilistically determined since quantum phenomena are probabilistic in nature, as dictated by the mathematical functions and equations by which they are governed.

There will be numerous, and perhaps an infinite many, slices that branch from the Right Now Slice into separate sequences, each corresponding to one of multiple solutions to the Schrodinger Equation for every quantum sub-system comprising the larger, composite state. In which case, “branching” is simply a natural consequence for every quantum process that occurs.

For example, radioactive decay is a purely probabilistic quantum process. At every given moment, the nucleus of an unstable atom has a certain probability of spontaneously emitting a particle. Until an unstable nucleus interacts with its environment (or until it is measured), it is in a superposition of “decayed/not decayed”. For every unstable nucleus, there is the possibility of decaying or not decaying at every possible increment in time down to the smallest scale (“Plank Time”).

Inside the core of a single star, there are about 10²⁰ decay events per cubic cm per second, along with many more potential decay events that don’t happen—an incomprehensible number. Even in a uranium-rich mine on Planet Earth, there are thousands of radioactive decay events per cubic cm per second.

But even with this staggering number of branches happening every Plank Time on earth alone, it is fair to wonder if they are making any appreciable difference at the macroscopic level. The probabilistic nature of individual nuclear events tends to "average out" over large scales, resulting in highly consistent overall decay rates when observed in large quantities. This stability and predictability over large numbers of atoms means that on a macroscopic level the rate of radioactive decay is consistent and doesn't typically cause abrupt, chaotic changes in the world we perceive around us. This is why radioactive dating methods are generally very reliable.

If this is the case, wouldn’t most of our parallel universes evolve identically from nearly every branching?

While this might be true in most cases, the difference between “decayed/not decayed” in a single or small number of radioactive atoms can produce divergent outcomes and cascading effects that accumulate to produce vastly different eventualities. A slight difference in radioactive decay events in a star’s core, well within reasonable statistical variance, could affect the balance of forces, influencing the timing or intensity of a supernovae explosion. Supernovae explosions play a critical role in seeding the cosmos with the elements necessary for life and complex chemistry. Radioactive atoms within a star’s core are subject to quantum rules, which means they exist in a superposition where virtually every type of supernovae explosion occurs and does not occur at every Plank Time. Think about the sheer number of branching events within the multiverse that are configured a little differently as a result. Think about the sheer number of different planets and solar systems and even galaxies—and every minute variation between—that take form at some point within the multiverse. Think about all the different kinds of life and histories and everything else. This alone produces a mind-boggling number of possible environmental settings, lifeforms within those settings, and individual beings within these lifeforms.

In the same vein, a specific radioactive decay event—or comparatively small number of them—could precipitate a cosmic ray traveling in any number of directions, each with the potential of influencing planetary atmospheres or impacting biological systems.

Even if we narrow our focus to the confines of our own planet, the cumulative effect of individual radioactive decay events could lead to variations in heat distributions in the earth’s mantle, driving movement of tectonic plates and affecting volcanic activity and mountain formation. In which case, it could be said that our own planet exists in a superposition of every possible state where every possible geothermal event occurred at every possible moment in time, giving rise to every possible geographic feature and geothermal dynamic.

But these are big picture events. It gets even more interesting if we narrow our focus to probabilistic quantum processes that could affect human lives on a personal, day-to-day basis.

Consider the example of uranium mines where radon gas, a decay product of uranium-238, is present. Radon emits alpha particles that, if inhaled, can damage lung tissue and potentially lead to cancer. The probabilistic nature of radon decay means the amount of gas released fluctuates randomly, varying from one branch of the multiverse to another. In one branch, a worker might be exposed to enough radiation to develop cancer, while in another, they are exposed to a lesser amount, sparing them from this unfortunate fate.

This is not due to some causal process that could be potentially calculated if all the information was known. Instead, it is an inherently probabilistic process in which the underlying equations imply multiple possibilities where each is just as valid or “real” as any other. Due to pure chance, one version of the worker could be exposed to enough to develop cancer while another version is spared.

Similar examples could be envisioned for hot particles and radiation spikes in nuclear waste facilities or factors that affect yield and reliability of nuclear weapons.

As Einstein once fretted could not possibly be true, it seems that God (i.e. math) does play dice with the universe—and with our very lives.

But what about quantum processes that can directly impact all humans and other neurologically centralized organisms, and not just those directly exposed to potential radioactive sources?

The Quantum Brain

In The Mathematical Universe, Max Tegmark offers one particularly astute example of a quantum process that commonly occurs within the brain which has the ability to influence macroscopic events and the trajectory of our individual lives. Within the brain, a single calcium atom can exist in a state of superposition, occupying multiple positions simultaneously. In one of these positions, it enters a particular synaptic junction in the prefrontal cortex, which determines whether a given neuron fires at a given time, triggering an electrical signal that in turn triggers a cascade of activity by other neurons in the brain. In the other position, it does not enter the synaptic junction, and this cascading effect does not materialize. Whether or not the calcium atom enters the synaptic junction can influence decision-making, potentially setting a person on two divergent courses in two separate branches of the multiverse.

Another intriguing theory that connects quantum mechanics to cognition is Orchestrated Objective Reduction (OOR). OOR is a theory developed by renowned physicist Sir Roger Penrose and anesthesiologist Stuart Hameroff in which they postulate that consciousness originates at the quantum level inside the neurons rather than being a product of neural connections. Critics of OOR argue that quantum coherence cannot be sustained in a wet, warm and noisy biological environment such as the brain. However, examples from nature, like magnetoreception in birds, suggest otherwise.

Magnetoreception is the leading theory for how migratory birds orient themselves and navigate during migratory season. It is the only credible theory explaining how a bird could sense the earth’s magnetic field, which is extremely weak. All evidence suggests it must be a radical pair mechanism that enables this capability, based on a quantum process where electrons in the cryptochrome proteins of their eyes become quantum entangled. This allows them to “see” the earth’s magnetic field. If quantum effects can be sustained within a bird’s eye—which is also wet, warm and noisy—then it must be possible that they could also be sustained within the brain.

Similarly, studies have linked quantum effects with photosynthesis, helping to explain how plants convert sunlight into energy with such remarkable efficiency. These examples suggest that quantum coherence can persist in biological systems, despite the chaos inherent in biological environments.

But a 2024 study offered the strongest support yet for OOR theory. The study confirmed that quantum effects occur in tryptophans, which are amino acids found in microtubules. This is significant because microtubules play an important role in OOR. Microtubules are cylindrical polymers made of tube-like proteins. They form part of the cytoskeleton, which serves as the structural support for the neuronal network, and they are particularly abundant in the axons and dendrites of neurons where signals are transmitted and received.

The lattice-like structure of microtubules creates cavities that could in principle facilitate movement of electrons, acting as conduits for quantum coherence and quantum information processing. Studies show that microtubules respond to electromagnetic fields, binding to various charged molecules and ions, providing opportunities for quantum entanglement and superposition.

This lends credence to the theory that quantum processes play a role in cognition. If OOR turns out to be even partially correct, then these quantum processes would influence timing and synchronization of neural firing, shaping the brainwaves that control how we think, feel and act—from mood to clarity of thought to whether or not we act on an impulse. If quantum processes are continually influencing brainwaves, then brainwave activity is inherently probabilistic. This would mean that our brainwaves exist in a state of superposition where every possible mental or emotional state at every given moment is realized in separate branches of the multiverse. Therefore, every possible manifestation is realized at every possible increment of time. This would undoubtedly impact events at the macroscopic level, since differences in emotional and cognitive states would cause every person and creature to think, feel and behave in different ways at every branching of the wavefunction. Every variation would then create a new set of conditions which would each lead to divergent outcomes over time.

Think about that time when you didn’t feel at your best and didn’t perform as well as you could have at that consequential meeting or interview. There is another version of you where a neuron fired differently, and your brainwaves oscillated in a more optimal pattern. In this branching, you were on point and nailed the meeting or interview which yielded new opportunities. Think about that time when your sour mood got the better of you and you said that thing you always regretted. There is another timeline where you handled it differently. Or that important decision you felt suddenly uneasy about. Or that time when you were in a certain mood which affected how you perceived something, and it forever changed your attitude about it even if you didn’t outwardly behave any differently in the moment.

These are events that happen numerous times per second throughout our lives, and their effects can be decisive and long-lasting. Every possible decision, every possible action and resultant outcome, every possible thought and feeling at every possible junction in time—and the sets of new possibilities cascading from each—all playing out in its own pathway in the infinite-dimensional conceptual space of the multiverse. And with every action there are an exponentially greater number of reactions which further proliferate the cloud of potentiality beyond comprehension.

It affects not only those who exist in a given version of the universe, but also whether or not specific individuals with specific genomes will exist at all.

For instance, let’ s say that you or your partner have decided to conceive, but one of you is not in the mood for sex at a particular moment. Maybe you put it off for a day, or even a minute. Already, this substantially changes the way your DNA will combine and the ensemble of traits inherited by the person you create into being. But the quantum effect makes it much more chaotic than even this. Recent evidence suggests that quantum randomness also comes into play to make possible an unlimited number of potential DNA combinations, even under identical circumstances—down to the molecular level.

Quantum Randomness in DNA Recombination

Genetic recombination is the process through which reproductive cells, also known as gametes (i.e. sperm or egg cells), are formed. It begins with meiosis, where germ cells are divided to form gametes. A human germ cell starts with 46 chromosomes, organized into 23 pairs, where one chromosome from each pair is inherited from either biological parent.

During the first phase of meiosis, a phenomenon called "crossing over" occurs. Segments of DNA are exchanged between paired chromosomes, creating new combinations of genetic material. This reshuffling increases genetic diversity, enabling 46 chromosomes to carry novel genetic configurations.

The germ cell then undergoes the first division (meiosis I), separating the chromosomes into two daughter cells, each containing 23 chromosomes. This is followed by a second division (meiosis II), where the sister chromosomes are separated into different cells, resulting in four reproductive cells (gametes) in all, each containing 23 haploid chromosomes. Haploid chromosomes represent a single set, which enables them to combine with another set (from reproductive partner) during fertilization to form a diploid cell. When a sperm cell and egg cell fuse during fertilization, the resulting zygote has 46 chromosomes (or 23 complete pairs), restoring the diploid number in the resulting offspring.

This process of DNA recombination depends on hydrogen bonding. Hydrogen bonding is an inherently quantum process where the proton is in a superposition of two locations at once, allowing it to be shared between the complementary base pairs. The base pairs are the sections of the nucleotide that form the “ladder rungs” of the familiar double-helix structure of DNA. These “ladder rungs” are actually two halves of separate base pairs that each protrude from their respective “spine”.

The hydrogen bonding connects the “ladder rungs” to form the DNA molecule. This bond is strong enough to stabilize the structure but weak enough to allow flexibility. This flexibility is essential for recombination, as it requires temporary separation and reattachment of DNA strands.

According to classical physics, a proton should either be on one side of a bond or the other, but the mathematical formulation of quantum mechanics allows the proton to exist in both places. This is known as quantum tunneling, since the particle appears to “tunnel” through the energy barrier, momentarily appearing on the “wrong” side of the bond. It seems impossible to human intuition, but it is the means by which stability is maintained between base-pair matches in DNA.

The structure of DNA is not even possible without the spooky effects of quantum mechanics. In the Many-Worlds Interpretation, each possible location of the proton corresponds to a different quantum outcome, and we’ve already established that different quantum outcomes equate to splits in the universe into parallel realities. In one branching, the proton remains in its usual position, stabilizing the expected base pair. In the other branching of the universe, the proton has “quantum tunneled”, forming a mispairing which leads to a spontaneous genetic mutation or allele coding.

The quantum tunneling effect of the proton can also determine the location of the crossover in recombination, which is the exact point on the chromosome where it is severed and changed out with the equivalent portion from its homologous pair. Quantum tunneling can subtly influence the stability of DNA at specific sequences, impacting where the DNA strand break occurs. Moreover, the enzymes involved in crossover events rely on electron and proton transfers to catalyze their reactions, also impacting crossover locations.

In every case, these quantum particles will exist in a state of superposition, splicing the chromosome at alternate points in parallel realities to give rise to an astonishing number of slightly and not-so-slightly varied versions of yourself and anyone or anything else that has ever lived. For every possible variation, there is one reality where you are born with a certain trait, or collection of them, and another reality where you are not. Perhaps the result is a metabolic difference leading to altered energy use or resistance to certain diseases; or cognitive or neurological variations that enhance or impair mental abilities. The examples are endless. These differences impact not only your own life, but also those of your descendants, where small variances accumulate into alternate histories and entirely divergent evolutionary trajectories across the branches of the multiverse.

Every gamete represents a vast number of potential variations of you, which is even more dizzying if you consider that the typical female produces a few million gametes over a lifetime, while the typical male produces trillions. Due to inherently quantum-probabilistic processes, no two possible variations are the same. To belabor the point, probabilistic processes equal branching events. Each potential reproductive cell represents a branching event in the multiverse where an exponential number of different combinations are actualized.

The evidence and the logic compel us to acknowledge that there must be an infinite, or virtually infinite, number of branching events occurring at every differentiable point in space and time. And not only this, but an infinite or near-infinite number of these alter macroscopic events to the extent that virtually every possible variation of history in every potential setting plays out along some thread in the boundless, virtual archive that is the multiverse.

The Subtle Cause is just the latest in what promises to become one of the most exciting and thought-provoking sub-genres as people continue to learn about the multiverse concept. Perhaps you will enjoy these creative explorations all the more knowing that almost everything really is possible in the quantum universe—where mathematical equations facilitate increasingly complex information processing, forming the basis for wonders such as sentient life and culture and all the enthralling stories flowing from them.