Justin Riddle explores the nature of consciousness from the perspective of recent breakthroughs in neuroscience, biology, computer science, and physics. Quantum computers and quantum biology are revolutionizing technology and science. What can these new advances teach us about ourselves?
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Knightian Freedom: Can a quantum computer swerve from determinism?
Episode 42
Sunday, September 7, 2025 • Duration 46:51
In this episode of the Justin Riddle Podcast, Justin dives into the concept of Knightian Freedom where large enough computational spaces become intractably complex to the point where maybe freewill is possible. The focus of this episode is a paper put out by Hartmut Neven (of Google’s Quantum AI Lab) and colleagues from 2021 entitled “Do robots powered by a quantum processor have the freedom to swerve?” This paper discusses how the exponentially large spaces that quantum computers evolve into are so large that they cannot be represented or simulated on digital computers. The size is so vast that it would take a computer the size of the universe computing for trillions of years to simulate even a few femtoseconds of the quantum computers that are about to be commonplace. Similar to modern AI, we will won’t be able to understand why a quantum computer generated the output that it did and perhaps this is the essential ingredient that leads to freewill. Rampant incomputable complexity is freewill. Second, Hartmut and colleagues propose a simple experiment to reveal whether or not there are additional factors that play into what output is generated by a quantum computer. Assume you run a quantum circuit that generates a perfect uniform distribution between many different possible outputs. Then, you observe that the quantum computer does not behave as if there was a uniform distribution, but instead selects one of those possible outputs more often. This is the ‘preference’ of the quantum computer. Next, you develop a circuit to amplify these deviations from uniformity with the intention of amplifying the probability of entering into that preferred state. Now, we have essentially created a ‘happy circuit’ which embraces the quirky preference of our quantum computer. Finally, you can correlate deviations from this happy state to psychological data in an effort to build up a taxonomy of subjective experiences that the quantum computer can enter into. Finally, you embed the quantum computer with its happy circuit into an artificial neural network such that errors produced by the AI push the quantum computer away from happiness and this unhappiness is fed back into the AI. Now we have created an AI system with quantum feelings! Will this newfound sense of subjectivity enable more effective AI systems or will the AI get bogged down by a spiral of despair and refuse to compute?! All of these questions and more are explored here. Enjoy!
Three Dimensions of Time: reconciling experienced time with physics
Episode 41
Sunday, September 7, 2025 • Duration 51:11
In this episode of the Justin Riddle Podcast, Justin explores a novel conceptualization of time as comprised of three distinct dimensions in an attempt to make sense of our subjective experience. Traditional physics does not account for the experience of always being in the present moment, time flowing from the past into the future, and the openness of the future versus the locked in events from the past. Often times we are told that our subjective experience of time is an illusion: that there is no validity to our experience of time and these are just made-up constructs in biology. We are skeptical of this dismissive approach to thinking about time. First off, there are sparse descriptions of the flow of time in physics with many descriptions viewing time as simply the fourth dimensions and being completely time reversible. The concept of entropy in physics accounts for some change through time because entropy (chaos) is described as always increasing from the past to the future. However, entropy is generated by simple laws of physics and yet when these time-reversible laws are run backwards – systems are seen to magically jump into alignment with each other. In sum, the description of time from simple physics forces does not provide a satisfactory explanation of our experience of time.
Our solution to the problem of time is to propose additional “dimensions” of time that go beyond physicalist framing. The dimensions are objective time, subjective time, and alternative time. We describe how subjective time is derived from our biological systems and represents the rate of information processing of the brain. Alternative time provides the various different options that a system could evolve into. Finally, objective time provides a universal frame for synchronizing all the various biological and physical clocks. Note, that there is a “three dimensions of time” theory from physics that emerged coincidentally around the same time that this video was posted. This theory differs in that our three dimensions of time are not akin to physical dimensions and possess qualitative differences from each other.
Finally, we discuss how the fundamentals of quantum physics and quantum computation provide a novel framing of time in that the measurement (or collapse of the wave function) produces a time-irreversible change that progresses the system into the future. We can conceptualize the evolution of the wave function of a quantum system as an exploration of the alternative time dimension and the rate of collapse of this system as some description of its subjective time dimensions. Objective time might correspond to Roger Penrose’s description of a Platonic realm where mathematical objects enter into the quantum computation and produce an objective progression via tapping into a universal frame of reference.
#40 – Nested Observer Windows: the case for hierarchical consciousness
Episode 40
Saturday, June 8, 2024 • Duration 01:23:45
In episode 40 of the Justin Riddle Podcast, Justin provides an update of the Nested Observer Windows (NOW) Model. The paper describing this theory was recently published in the open-access Neuroscience of Consciousness journal (link below) and this video is an extended version of the Plenary talk that Justin gave at the Science of Consciousness conference in April of 2024 in Tucson, AZ (link below to conference recording). The NOW Model describes the mind as a nested hierarchical system in which there are many different cognitive systems within the brain at multiple scales. We are familiar with neuron-centric theories of consciousness, and yet why are we so fixated on the level of the neuron. There are synapses that comprise the neuron, there are microtubule systems within the neurons that appear to be electrically active, and there are neuronal population dynamics above the neuron which display prominent electrical properties. The cellular level is one level within a multi-scalar system. Evidence from cognitive neuroscience is suggesting that the low-frequency macroscopic electrical activity in the brain is closest correlated to cognition and brain stimulation techniques that drive these neural oscillations can reproducibly create changes in cognition. Therefore, it appears that these macroscopic scales are “causally” relevant to cognition. How then do all of these multiple levels connect to each other?
Observations from neuroscience show us that these multiple scales are electrically coupled to each other, a phenomenon called cross-frequency coupling. With coupling across these multiple scales, there is a mechanism for how information processed at different scales can be communicated up and down the nested hierarchy of the brain. The NOW Model essentially takes cross-frequency coupling very seriously. Your mind is at the apex, the top, of the brain hierarchical system and there are nested cognitive processing systems within you. A model by which there are nested cognitive systems explains a whole range of psychological phenomena that are not current explainable under single-level neuron theories of consciousness. For example, the fact that we are only aware of a high level of abstraction of our experience and yet can interact with a rich perceptual landscape and initiated complex motor movements can be explained by an interaction between ourself at the slow apex and the lower levels. Another explanation is how slow our cognition really is: the NOW Model suggests that we are operating in the time range of 1 cycle per second or even slower. Our thoughts are sluggish and filled with abstraction (perhaps a key to intelligence) but contain the richness of the faster systems. Beyond capturing a deeper range of every day experiences, the NOW Model also readily accounts for dissociative identity disorder and new psychotherapy techniques that conceptualize the self as a family (internal family systems). This is just the tip of the iceberg from changing our self-conceptualization from singular into a multiplicity of nested systems. There is a lot of work to be done in this space to validate the potential cognitive reality of the NOW Model!
#39 – The Problem with Natural Selection: exploring modern mechanisms for evolution
Episode 39
Sunday, March 31, 2024 • Duration 42:09
In episode 39 of the quantum consciousness series, Justin Riddle explores the mechanism behind natural selection in evolution. This is not a question about humans evolving from animals, but instead is raising the question about what is the driving force behind the process of evolution. Charles Darwin described evolution as a random expression of features that are then selected by the environment. The animals that are able to reproduce will preferentially spread their features to next generations. Gradually, species will change based on these survival pressures. The problem with this model is that the random expression of features and then reproduction is an extremely slow process. While including the expression “then add millions of years” appears to be sufficient at first glance to account for such slowness, a truly random process that is this slow will never build anything sufficiently complicated. Humans are notoriously terrible at appreciating exponentials and combinatorics: a deck of cards will likely never be shuffled into the same pattern twice even if billions of people frantically shuffled decks of cards across the planet for a million years. If the core force of evolution is “randomness,” then the probability of repeatedly creating novel stable biological structures such as the liver or the immune system is vanishingly small. Luckily, there is no reason to be stuck in 1800s ways of thinking since we live in the modern information age with advanced digital computers and quantum computers on the horizon. A simple update to natural selection is to acknowledge a domain of algorithms and “Platonic” / mathematical forms that are being carried out in evolution. The creation of a novel organ could arise through the combination of novel algorithms rather than combing “physical” parts in a random manner. However, a core hurdle of digital computer models of life is the need for a programmer. Without a programmer, digital computers are just more random physical elements unlikely to create anything. While we are just at the emergence of quantum computer technology, quantum computers might express a naturally occurring form of computation that does not require explicit programming. Quantum computation at the core of evolution would not be random and would further emphasize the importance of a single processing unit in the organism – the mind. Consciousness as a quantum computer would be critical to the evolution of the species. Your choices and thoughts are the evolution of your body and by extension the human species. Finally, the goal of evolution might not just be the furthering of your life, but if we take human knowledge to actually be real, then using your life to contribute to education, science, and medicine actually makes a difference to the human species. An expanded view of evolution includes expanding the domain of collective human knowledge, the experience of the individual, and the creation of a flourishing society.
#38 – Reject the Multiverse: taking wave function collapse seriously
Episode 38
Sunday, March 31, 2024 • Duration 42:10
In episode 38 of the quantum consciousness series, Justin Riddle takes on the concept of the multiverse and provides arguments for why he thinks we live in a single universe. The concept of the multiverse arose from the recognition that at the fundamental level quantum systems are splitting into different possible futures. This split in space-time reality if taken at face value implies that the universe is splitting into multiple parallel universes in which slightly different events take place. However, quantum mechanics is also faced with a measurement process by which these parallel universes are destroyed and “collapsed” down to a single reality of what actually happens. This duality between a superposition of multiple possible realities and a measurement that reduces the probability space down to a single universe is the fundamental mystery at the heart of quantum mechanics. The tricky bit is that we live in a culture that more readily accepts the multiverse interpretation of quantum mechanics and is hesitant to dive into the murky depths of wave function collapse theories. For example, Roger Penrose describes a mechanism why which wave function collapse occurs at a specific threshold because these parallel universes in possibility space are unstable and collapse. This “objective reduction” theory of wave function collapse is still mostly considered as a fringe and unsubstantiated theory (although the times are slowly changing). To assert the universe and reject the multiverse is to take wave function collapse seriously!
As we enter the quantum information age, society will start to get used to thinking about a digital information state that is chosen as input into a quantum computer, then from this state a wave function evolves and these possible realities interfere with each other. Finally, the system is measured again and digital information is extracted from the system. Computation in the future will be a hybrid of digital and quantum computation in a dualistic interplay. From this perspective, the idea that each of those possibilities is dissociated from each other into a multiverse just does not fit with the idea of interference patterns and quantum computation. If all the suboptimal solutions of a quantum computation are different parallel universe that never interact, then this undermines the concept of quantum computation.
Finally, at the core of the multiverse is the idea that everything is random and nothing happens for a reason. We just happen to be in the universe that worked out despite countless failed universes all around us. This mechanism of action at the core of the idea is a bit too overly simple and reverts into more nihilistic physicalism. From a human outlook, the multiverse is another tenant of nihilism that challenges the idea that your choices matter, you are real, and there is something meaningful occurring in the universe.
#37 – Decorated permutation in conscious agents: an interview with Donald Hoffman
Episode 37
Friday, August 4, 2023 • Duration 01:13:23
In episode 37 of the quantum consciousness series, Justin Riddle takes a deep dive into Donald Hoffman’s conscious agent model and relates it to the leading theories of quantum consciousness. The structure of this episode is an introduction to Hoffman’s model of conscious agents, then an interview with Don Hoffman in November 2022, and finally some reflections on the implications of this model. Hoffman begins by describing the interface theory of perception: we have mistaken the external “physical” world to be fundamental reality. But this external world that we see around us is an evolved interface that was created through billions of years of evolution and cannot be trusted. The world you experience is like a video game – with icons, side quests, and abstract motivations to win victory points. The “real” world is not directly accessible to us through our perceptual systems and there is a great illusion at play. Hoffman then proposes his Conscious Agents theory, in which the universe is comprised of conscious beings interacting with each other. He describes these conscious agents as Markov Chains – probabilistic systems that move through a set of possible experience and action states while learning from their interactions with the world at large. Finally, he proposes that conscious agents are composed of conscious agents resulting in a fractal nested hierarchy of beings from the scale of the entire universe down to the Planck scale. This nested hierarchy is fundamental and now just needs to be mapped into modern particle physics in order to complete his theory of everything. Here, he introduces “decorated permutations” which are a way to map the Markov Models of his conscious agents into geometric structures. With this mapping, he claims to connect his agents to fundamental geometric forms at the core of reality, such as the amplituhedron, and then that amplituhedron can derive space-time, particle physics, and quantum mechanics. His theory is very Platonist in its essence and relies on a geometric depiction of reality. At the end of the episode, I praise the ability of Hoffman’s theory to connect the nested hierarchies of beings into a substrate for mathematical forms to arise, but also caution that his model throws away the physical world and mental world to some degree to focus exclusively on the Platonic world of forms. Living within a hyperdimensional geometric form may result in the same nihilistic conclusions that our lives are just unfolding as sub-projections of this universal form. Can we salvage the human spirit from unmoving crystalline geometry? I hope you enjoy!
#36 – Quantum Simulation Theory: the limitations of simulating a quantum reality
Episode 36
Monday, June 26, 2023 • Duration 44:39
In episode 36 of the quantum consciousness series, Justin Riddle describes the popular simulation hypothesis and discusses the implication of running the simulation using quantum computers. First off, Justin makes the argument that the foundation of the simulation hypothesis is strictly based in a digital computer framework. If the world is deterministic and digitizable, then it could in principle be simulated. But, if the world is quantum mechanical – with superposition, measurement, and entanglement – then the world might be non-deterministic or require simulation of the entire universe to capture all the necessary information to make the simulation perfect. Luckily, quantum computer scientists have been working on the concept of simulation for decades. Universal quantum simulation is the theory that if you set up a quantum computer to have the same inputs and the same quantum circuit, then you will get the same probability distribution on different quantum computers. However, when you measure that output, then you get a random digital output drawn from that probability distribution. This means that you can simulate the wave function but measurement fundamentally disrupts the simulation and creates divergence. If you were attempting to simulate a quantum system, then you simulation would start to diverge with each subsequent measurement and by the time you are multiple measurements into the future, reality might be unrecognizably different from the simulation. This massively reduced the controllability and the conclusion is reached that a quantum simulation that fully approximates the world is not sustainable for any substantial amount of time. Second is the problem of scaling. In a digital computer, you can write code that derives a more complicated world from some simple principles. However, in a quantum system, the informational complexity of the system explodes exponentially at every evolution of the wave function. Scientists running quantum simulations of molecular interactions for example are looking to create quantum computers with comparable complexity to those chemical systems in order to simulate them. This is a challenge for the simulation hypothesis because the creator of the simulation would need to have a computer as big as the universe itself in order to run the simulation – there does not appear to be any effective compression techniques for quantum computers. Third, the no-cloning theorem of quantum mechanics states that each wave function is uniquely identifiable and cannot be copied in principle. While the probability distribution of a quantum system can be approximated by other quantum computers, the array of entanglement relationships of a quantum system to the world at large cannot be simulated. This means that any quantum simulation will not be a perfect replication in principle, which could lead to an uncanny valley where the simulation is missing something and appears fake despite attempts to enhance the realism. With all of these metaphysical arguments in mind, there is still a persistent phenomenology of feeling like you are in a simulation. For example, high doses of psychedelic drugs can induce the dissociative feeling that everything around you is fake and this is the first moment of your life. If you were a quantum computer living within a physical brain, then the experience of accessing the data of your brain might be akin to the feeling of living in a simulation. Here you are in the moment collapsing the wave function and entering unique moments of time, but the data you are accessing in your brain contains the narrative construct of your life and knowledge. Hence, a removal of typical “neural access” might create the perception of living in a simulation. Lots to think about in this one! Hope you enjoy
#35 - Digital AI is not Conscious: the role of quantum computers and the mind in the AI revolution
Episode 35
Monday, June 26, 2023 • Duration 41:02
In episode 35 of the Quantum Consciousness series, Justin Riddle explores the role of quantum computers in the current revolution in digital artificial intelligence (AI). First, Justin describes some of the basics of large language models at a high level. In essence, digital AI can be conceptualized as a series of weighted matrices trained by fitting and updating the weights according to patterns found in extensive training sets of data. While these digital AI systems are indeed quite powerful as tools, it is important for us to determine what "knowledge" is being acquired. One option is that there is no universal truth, and meaning is arbitrary. This viewpoint leads to the most significant perceived risk: that this AI might start optimizing for arbitrary values that do not align with human values, the classic example being turning the planet into a massive paperclip factory. This "alignment problem" is what leads people to assert that we need a moratorium or ban on these AI systems.
However, the alternative viewpoint is that there is a universal truth at the core of reality, akin to Plato's world of forms or mathematics. If mathematics is universal, then there are two subsequent outcomes. Either the digital AI can fully map this Platonic world of math, or it can only approximate these forms. Given arguments from Gödel's incompleteness theorem and the residual mystery of quantum mechanics, it is unlikely that digital systems of formal logic will be able to map mathematics fully. Thus, we are left in the middle ground: there is a universal truth, and digital AI is approximating aspects of this universal truth.
The second topic of the episode is the role of quantum computers with respect to digital AI. Justin describes how digital computers represent the ultimate mastery of the physical aspect of reality, while quantum computers are composed of the fundamental pieces of the universe. At the very least, quantum computers will provide an exponential speedup in the training and execution of digital AI, but are also likely to deviate substantially from digital AI because there are additional aspects of their functioning that remain mysterious. How will the digital AI revolution and the quantum revolution compare?
Digital AI will significantly expand our capacity to remember, access, and learn information, but this is a physical tool that will be external to our bodies and minds. However, if the mind is truly a quantum computer, then quantum computer technologies will likely need to be implanted within the nervous system to directly expand the computational capacity of your mind. At the end of the episode, Justin speculates that the expansion of the mind with quantum technology may inadvertently lead to transcendent experiences that defy our current understanding of ourselves and our place in the universe. It sure is an interesting time to be alive on this planet!
#34 - In defense of freewill: three ways that consciousness might collapse the wave function
Episode 34
Monday, March 27, 2023 • Duration 39:34
In episode 34 of the Quantum Consciousness series, Justin Riddle puts forth a defense of freewill. In a deterministic universe guided by physical principles, there is no room for freewill. Surely, we must succumb to the crushing reality that our choices do not matter, that the self is an illusion, and that the very concept of time is illusory – nothing more than a social construct or hallucinations. While this is indeed the typical mainstream opinion on the state of our consciousness, quantum mechanics offers some chance that we could escape from determinism. The Schrodinger’s equation explains that quantum systems evolve into a superposition of multiple different possible futures. Then, upon measurement, the wave function of possibilities collapses into a definitive reality. But this process is apparently random. The stochastic (random) nature of this process leaves room for something beyond pure determinism. Perhaps it is simply probabilistic, and not deterministic, or perhaps there is some chance that consciousness could impose its will on this collapse process. At the very least, if freewill is not illusion, the only apparent room for its influence is at this moment of collapse.
In this episode, we explore three different ways in which freewill could find its way into the collapse of the wave function. In the first model, the superposition provides the choices for possible futures. These choices are given to the mind, and the mind chooses which of these options to collapse into the physical world. Henry Stapp and John von Neumann postulated that this could be the case, but there must be additional checks from nature on this multiple-choice selection process. The second framing is through the quantum Zeno effect, where you have the option to pay attention to some series of thoughts or to let those thoughts go. This ability of “free won’t” could be a way by which the mind is able to influence the rate and timing of collapse of the wave function rather than the actual choice within the probability distribution. The third and final way that is presented is defined as “form will”. In this model, the human mind chooses a set of values, or forms, that are applied to a situation. Instead of choosing a particular behavior or response, the mind applies a flavor of quantum algorithms to the problem and then whatever the resulting output of that quantum computation is will determine the actual actions that are carried out. In all, each of these three manners for freewill to influence the physical world are speculative and require there to be large-scale quantum computers within the brain. In my opinion, these new models of freewill are necessary for us to escape the crushing nihilism that is inherent to a physicalist / determinist reality.
#33 – Testing consciousness causes collapse: an interview with Kelvin McQueen
Episode 33
Wednesday, February 15, 2023 • Duration 01:32:48
In episode 33 of the Quantum Consciousness series, Justin Riddle interviews Kelvin McQueen on his recent theory on how consciousness might collapse the wave function. Kelvin is a professor of philosophy at Chapman University who investigates the nature of consciousness and role it might play in quantum mechanics. The measurement problem in quantum mechanics is that there is a smoothly and deterministically evolving superposition that is abruptly “measured” and reduced to a finite physical state, but it is unclear what constitutes a measuring device. In collaboration with David Chalmers, Kelvin explores the hypothesis that the measurement device in quantum mechanics might be consciousness. However, consciousness is typically an ill-defined vague idea that does not produce any tangible upgrade to the mystery of what a measuring device is. Here, Kelvin uses the definition of consciousness from integrated information theory (IIT) by Giulio Tononi. Consciousness is the minimally reducible information state of a system, which is defined as a recurrent network of interconnected nodes that predict the next state of the system. According to Kelvin, this definition allows for testable predictions to be made regarding the role of consciousness. In the upgraded quantum IIT theory, the nodes are quantum bits (or qubits) and the edges are entanglement relationships. Thus, QIIT defines an interconnected quantum computer (of sorts…) as consciousness and this reduces the wave function. Furthermore, the collapse of the wave function is not instantaneous but instead is continuous, drawing from the continuous spontaneous localization theory of quantum mechanics. Altogether, these ideas present a picture where consciousness is integral to a fundamental description of the physical universe and might provide room for an expanded sense of self. In this interview, I interrupt intermittently to describe the relevant ideas with graphical representation and compare this model to the Orchestrated Objective Reduction model by Stuart Hameroff and Roger Penrose. There are some amazing new ideas that Kelvin McQueen describes in this episode, so be sure to check it out!
