The concept of randomness has fascinated humans for centuries, from the flip of a coin to the roll of a dice, and in modern times, to the algorithms that generate random numbers for our computers.
At first glance, randomness seems like a simple idea—it’s what we call events that we cannot predict or that seem to occur without pattern. But when we dig deeper, randomness becomes far more complex and elusive, especially when we consider the deterministic nature of the universe.
Is randomness truly random? Or is what we perceive as randomness simply the product of ignorance—our lack of complete information about the universe?
To explore this question, we need to look at randomness in both the classical physical world and the quantum realm and consider the implications of space-time on our understanding of events.
Modern Digital Randomness
You may have used a random number generator for lotto numbers or shuffled a playlist to play songs in random order. These tasks are common, and they rely on the idea that computers can generate random numbers. But in the world of computers, the randomness we rely on is often not truly random.
When you ask a computer to generate a random number, it uses an algorithm, and algorithms, by definition, are deterministic. This means that, if you knew the exact algorithm and the initial conditions (called the seed), you could predict the next "random" number.
But does that make these numbers less random in practice? For example, if you generated your lotto numbers using a computer’s random number generator, does it mean you have a lower chance of winning? Not really. For most people, if they don’t know the algorithm or the seed, the sequence of numbers will appear unpredictable—indistinguishable from true randomness.
This is where pseudorandom number generators (PRNGs) come into play. They simulate randomness through sophisticated algorithms that make predicting the numbers extremely difficult—impractically impossible in many cases—but not impossible.
In fact, they behave as if they are random and don’t necessarily reduce your chance of winning a jackpot. However, the problem remains that these numbers are still not truly random.
For example, Cloudflare, a company that handles internet security and encryption, famously uses lava lamps to generate randomness. A camera records the movement of the lava lamps, and the constantly shifting blobs of wax introduce unpredictability into their encryption processes. This randomness is used as entropy, or chaotic input, to make cryptographic keys harder to predict.
So, if you can’t predict the numbers, does it make them random enough? Or is this "randomness" simply a product of our inability to comprehend the hidden patterns?
Why Can’t We Generate True Random Numbers?
The fundamental reason we can’t generate true random numbers on a computer is that computers are deterministic machines. They follow strict instructions (algorithms) designed by humans. Every step is predictable if you know the inputs and the program’s logic. When a computer generates random numbers, it uses a pseudorandom number generator (PRNG), which is based on mathematical formulas. These PRNGs rely on an initial input, called a seed, to produce a sequence of numbers that appears random. But if you knew the seed and the algorithm, you could predict the entire sequence.
This kind of randomness is what we call pseudorandomness. While pseudorandom numbers work well for most purposes—like simulations, video games, or simple shuffling—they are not random in the truest sense. They are deterministic. If you were to restart the generator with the same seed, you would get the same sequence of numbers every time.
However, predicting pseudorandom numbers in practice can be incredibly difficult, especially if the algorithm is sophisticated or if the seed is unknown. In these cases, even though the numbers are not truly random, they may be "random enough" for most applications.
When Is Pseudorandomness Enough?
For most of us, randomness is just a matter of perceived unpredictability. If you can’t guess the next number in a sequence and it looks random to you, that’s often good enough. This is especially true when it comes to things like shuffling music playlists, generating random opponents in games, or randomly assigning tasks.
However, in security and cryptography, the stakes are much higher. If the numbers used to encrypt data can be predicted, even with a small chance, the entire system can be compromised. That’s why companies like Cloudflare go beyond traditional PRNGs and look for truly random sources of entropy. Using physical processes like lava lamps or measuring quantum fluctuations, they gather input that is not only impractically impossible to predict but also influenced by unpredictable real-world factors.
While true randomness is hard to achieve on a computer, when combined with external inputs like environmental noise, it can get close enough to secure critical systems.
But let’s step back. If you don’t know the algorithm behind a PRNG or if predicting the next number is nearly impossible, does that make it truly random? Or does it mean that randomness is simply a reflection of our ignorance of the underlying system? And what if randomness itself isn’t as random as we think?
The Deterministic Universe Hypothesis
At the root of this discussion lies the age-old question: Is the universe deterministic? In a deterministic universe, every event is the inevitable consequence of prior conditions. From the behavior of the smallest particle to the orbit of planets, everything is governed by cause and effect, operating under the immutable laws of physics. If this is true, then nothing is truly random; it only seems that way because we lack the full picture.
Let’s begin with a simple example—rolling a die. On the surface, it seems random. But in a deterministic universe, the outcome of that roll isn’t random at all. It is fully determined by a number of variables: the initial position of the die, the force applied when it is thrown, the angle at which it leaves your hand, the friction of the surface it lands on, the air resistance, and even the gravitational pull of the environment.
If we could measure all these factors with absolute precision, we could theoretically predict the outcome of each roll before the die lands. What appears to be random is simply the product of a complex interplay of forces, which, if known, would lead to a predictable result. This highlights a crucial point: randomness, in this sense, is a reflection of our limited knowledge or inability to calculate all influencing factors in real time.
Determinism in Nature: The Chain of Events
Now, consider more complex natural events, like a lightning strike, a sudden thunderstorm while you’re preparing for a beach day, or a shooting star streaking across the night sky. On the surface, these events seem like unpredictable surprises. But in a deterministic universe, each of these occurrences is the outcome of an unbroken chain of cause and effect.
For instance:
- A lightning strike could be traced back to complex atmospheric conditions involving temperature, pressure, and humidity interacting in ways that, with enough data, we could predict.
- A sudden downpour as you’re heading to the beach might feel random, but meteorologists could explain it as the result of air currents, moisture levels, and climatic interactions that began hours or even days prior.
- Even a shooting star could be predicted, as it results from a small chunk of debris entering Earth’s atmosphere at a specific angle and speed, which itself was determined by the debris’s trajectory through space and its interactions with gravitational fields over millions of years.
From this viewpoint, even the most seemingly spontaneous events are nothing more than the unfolding of physical laws. Their “randomness” only exists in our minds, as we are incapable of knowing all the variables leading up to them. But a universe governed by deterministic laws means that, given enough data and computational power, these events could be predicted just as easily as the outcome of a coin toss or a roll of the dice.
The Universe’s Seed Value: Tracing Everything to the Big Bang
If the universe is deterministic, then everything that has happened and will happen, from the formation of galaxies to your decision to read this article, could be traced back to a single point: the Big Bang, the "seed" of the universe. Just as a computer’s pseudorandom number generator (PRNG) uses an initial seed value to determine the sequence of numbers it produces, the universe could be seen as having a similar "seed"—the state of the universe at the very beginning of time.
Imagine a PRNG in a computer, where a number sequence is generated based on a simple seed, such as the current time. If you knew the algorithm and the seed, you could predict the entire sequence of numbers, even though they might appear random at first glance. Similarly, in a deterministic universe, if you knew the exact conditions of the universe at the moment of the Big Bang—the original seed value—you could, in theory, predict everything that would follow. Every event, every thunderbolt, every moment of human experience could be calculated based on the unfolding of that initial state.
From this perspective, nothing is truly random—not even the most chaotic or unpredictable events. What we perceive as randomness is merely an illusion, a reflection of our incomplete knowledge and our inability to measure or calculate the infinite variables that govern each event. The universe is like an enormous PRNG, with the Big Bang as its seed, and every moment of history as part of its sequence.
Quantum Mechanics: The Last Bastion of Randomness?
Quantum mechanics seems to challenge the deterministic worldview. At the quantum level, certain processes—like the decay of radioactive atoms or the behavior of particles in a superposition state—appear to be inherently probabilistic. According to the mainstream interpretation of quantum mechanics, we cannot predict the outcome of a quantum event with certainty; we can only describe the probability of different outcomes.
But is this truly random, or are we simply missing something? Some physicists propose that quantum mechanics might involve hidden variables that, if understood, would reveal the underlying determinism behind what we currently see as randomness. In this view, quantum uncertainty is not a fundamental feature of reality but simply a reflection of our incomplete knowledge of the system.
If this is true, then even quantum events—long considered the purest example of randomness—are not truly random but just another example of deterministic chaos beyond our comprehension.
Space-Time and the Context of Events
Let’s take this idea even further. If every event occurs in a specific space-time context, then that context itself influences the event in ways we may not fully understand. This leads to the intriguing idea that randomness is always tied to space-time. Every event that we call random—whether it’s a die roll, a coin flip, or a quantum fluctuation—is shaped by the exact moment and place in the universe in which it occurs.
If we think of randomness this way, we realize that no event could ever happen exactly the same way twice. Each moment in time is unique, each arrangement of particles in the universe is one-of-a-kind, and thus the conditions surrounding the event will never be perfectly replicated. This means that what we call random may just be the outcome of complex processes within the fabric of space-time, where no two moments are alike.
Under this view, randomness becomes relative: while events might appear random to us, they are always deeply connected to the specific conditions of the universe at that exact time and place. In this way, randomness might simply be the product of extreme complexity rather than the absence of order.
Complexity vs. True Randomness
This brings us to a key distinction between complexity and true randomness. A coin flip might seem random because we can’t account for every tiny interaction—the initial force, air resistance, and minute imperfections in the coin. But in principle, if we had perfect knowledge of every variable, we could predict the outcome. The complexity of the system hides the fact that it is deterministic.
The same is true for computer-generated random numbers. While they might seem random to the observer, they are deterministically generated based on an algorithm and a seed. We could predict the entire sequence if we had enough information. The randomness we perceive here is not true randomness but complexity beyond our ability to process.
In a universe governed by deterministic laws, the same argument could apply to quantum events. Just because we can’t predict an outcome doesn’t mean it’s random. It could be that the complexity of space-time interactions at the quantum level makes it impossible to fully understand the causes behind each event.
Randomness as a Product of Ignorance
In this light, randomness becomes a product of ignorance. We perceive events as random because we lack the complete knowledge needed to predict them. Our inability to measure or account for every variable in a system—especially a complex or quantum system—gives rise to the appearance of randomness. But if we had perfect knowledge of space-time and the laws governing every interaction, we might see that everything is determined.
In this worldview, randomness is an illusion. There is no such thing as true randomness—only unpredictability due to our limited understanding. Even the most chaotic, unpredictable events in the universe could be predicted if we could see the entire picture.
Does True Randomness Exist?
So, does true randomness exist? If you believe in a fully deterministic universe, the answer is no. Everything, from the spin of a particle to the roll of a die, is determined by prior states and the laws of physics, even if we can’t predict it.
On the other hand, if you accept the mainstream interpretation of quantum mechanics, then true randomness might exist at the quantum level—a fundamental uncertainty baked into the nature of reality. But even here, the debate over hidden variables leaves room for doubt.
In the end, randomness might simply be a matter of perspective. To us, events appear random because we cannot see the intricate web of causes that lead to each outcome. But in the grand scheme of the universe, everything may follow a pattern—one so complex that we can never fully grasp it.
Advantages of Unrandomness
It might sound counterintuitive, but there are many cases where controlling randomness to suit specific purposes yields better results than pure randomness. One such concept is Adaptive Randomness, used in software engineering for Adaptive Random Testing (ART).
In this approach, randomness is strategically adjusted to ensure better coverage of a domain, particularly in scenarios where randomness might not evenly distribute values across a range.
Randomness, while unpredictable, may lead to clusters or gaps in generated values. For example, if you're tasked with generating 10 random numbers within a domain from 1 to 100, it’s entirely possible—under a random model—that many of the numbers could fall close together, say between 70 and 90, leaving large portions of the range unexplored.
In testing environments, this uneven distribution can be problematic. Imagine testing a complex software system where the input range is large, and the system could behave differently depending on which parts of the range are tested. If random inputs are clustered in one area, there’s a risk of missing critical failures that could occur elsewhere in the range.
Adaptive Randomness aims to mitigate this problem by ensuring that random inputs are more evenly distributed across the entire range. Instead of allowing pure randomness to dictate the distribution, adaptive randomness ensures that different areas of the input space are covered more systematically.
For example, say you need to generate 10 random numbers between 1 and 100. Using adaptive randomness, you might structure the randomness such that:
- The first number falls between 1 and 10,
- The second number falls between 11 and 20,
- The third number falls between 21 and 30, and so on.
This way, you ensure that the entire range from 1 to 100 is evenly sampled without any large gaps or clusters. The random numbers are still unpredictable within each subrange, but the approach guarantees a more comprehensive coverage of the entire domain.
Empirical studies have shown that ART can achieve better failure-detection effectiveness compared to random testing. The reason is simple: by evenly distributing test cases across the input space, adaptive randomness reduces the likelihood of missing critical failure points that could be located in under-sampled parts of the range.
By the way, in this context the randomness is technically pseudorandom, as it is generated algorithmically. However, adaptive randomness is deliberately "less random"—it is shaped to be more strategic in how it spreads test cases. This structured approach tends to deliver better results in testing because it focuses on maximizing coverage while maintaining unpredictability within each subrange.
Is Random Randomly Random?
From the dice in our hands to the stars in the sky, randomness touches every part of our lives. Yet, it seems, randomness might not always be—or need to be—truly random.
We began with a simple question: Is random truly random? The answer, as it turns out, is both yes and no, depending on how we perceive the universe. If randomness is defined as unpredictability, then many processes—such as dice rolls, weather patterns, or even quantum events—appear random because we cannot foresee their exact outcomes. However, if randomness is about true indeterminacy, the answer becomes far more nuanced.
In a deterministic universe, randomness may be nothing more than an illusion—a reflection of our incomplete knowledge of the myriad variables that govern each event. Every "random" number, every unpredictable outcome, may still be shaped by the unyielding laws of physics and the specific space-time context in which it occurs.
Whether randomness is a fundamental property of reality or merely a product of complexity and ignorance, it remains one of the most profound and intriguing mysteries of our existence.
