Koperski, Jeffrey. 2026. 'Quantum Mechanics and Theology', St Andrews Encyclopaedia of Theology. Edited by Brendan N. Wolfe et al. https://www.saet.ac.uk/Christianity/QuantumMechanicsandTheologyKoperski, Jeffrey. "Quantum Mechanics and Theology." In St Andrews Encyclopaedia of Theology, edited by Brendan N. Wolfe et al. University of St Andrews, 2022–. Article published May 12, 2026. https://www.saet.ac.uk/Christianity/QuantumMechanicsandTheology.Koperski, J. (2026) Quantum Mechanics and Theology. In: B. N. Wolfe et al., eds. St Andrews Encyclopaedia of Theology. University of St Andrews. Available at: https://www.saet.ac.uk/Christianity/QuantumMechanicsandTheology [Accessed ].Jeffrey Koperski , 'Quantum Mechanics and Theology', in St Andrews Encyclopaedia of Theology, ed. by Brendan N. Wolfe et al. (University of St Andrews, 2026) <https://www.saet.ac.uk/Christianity/QuantumMechanicsandTheology>
1 Introduction
Quantum mechanics is one of the principal achievements of twentieth-century physics. It replaced the intuitive framework of classical mechanics with a theory whose basic features challenge our understanding of reality. Quantum mechanics tells us that systems can exist in classically incompatible states (superposition), that matter has both particle and wavelike properties (duality), that distant particles are sometimes part of a single system (entanglement), and that not all events are uniquely determined by the laws of nature and antecedent conditions (indeterminism). These quantum phenomena not only brought about changes to physics, but to the underlying metaphysical picture of the world.
This radical departure from classical physics attracted theological attention almost from the beginning. Within five years of its founding, James Jeans said that the quantum mechanical ‘universe begins to look more like a great thought than like a great machine’ (1930: 136–137). But quantum mechanics was both mathematically difficult and philosophically unsettled in its early years. Theologians interested in science instead turned most of their attention to Big Bang cosmology and evolutionary biology.
Theologians have more recently found that quantum mechanics opens new avenues of thought, particularly for theories of divine action. As Jeans suggested, physicists no longer conceived of nature as the closed, mechanistic system of classical mechanics. This shift prompted significant attention, including a series of influential volumes published jointly by the Center for Theology and the Natural Sciences and the Vatican Observatory. Notable among these were Chaos and Complexity: Scientific Perspectives on Divine Action (1996) and Quantum Mechanics: Scientific Perspectives on Divine Action (2001).
More recently, attention has shifted away from divine action toward extracting insights from quantum mechanics to address theological puzzles (Wegter-McNelly 2011; Harris 2023). Phenomena like wave-particle duality provide resources for understanding classical paradoxes, and quantum entanglement suggests models for divine omnipresence and trinitarian relations. On the other hand, new theological challenges have emerged from quantum cosmology regarding traditional formulations of creation ex nihilo and the problem of evil.
Not all applications of quantum mechanics to theological questions have been well received. Beginning in the 1970s, popular works such as Fritjof Capra’s The Tao of Physics (1975) and Gary Zukav’s The Dancing Wu Li Masters (1979) drew parallels between quantum mechanics and Eastern mysticism. These and similar efforts are now widely regarded as pseudoscientific – what physicist Murray Gell-Mann called ‘quantum flapdoodle’ (Shermer and Stenger 2009: 7). The concern is not that quantum mechanics has no broader implications, but that such works exploit superficial similarities of language rather than genuine conceptual connections. Avoiding this pitfall requires attention both to the physics itself and to philosophical questions about models, metaphors, and analogical reasoning.
This article will proceed as follows. Section 2 examines how particular quantum phenomena have been used to illuminate classical doctrines by way of analogy and metaphor. Section 3 turns to the epistemic limitations imposed by quantum mechanics. Section 4 considers two aspects of quantum cosmology: first, how quantum fluctuations might provide insight into creation ex nihilo; second, the challenge that the many-worlds interpretation presents for the doctrines of creation and theodicy. Section 5 discusses indeterminism and models of divine action, considering how God might act through indeterministic quantum events without violating the laws of nature. Section 6 explores the relation between quantum measurements and consciousness. Section 7 looks at two broad perspectives for further thinking about physics and theology.
The framing of many issues in this entry presupposes or is most naturally suited to the orthodox or ‘Copenhagen’ interpretation of quantum mechanics. Other interpretations will not agree on every point, and where differences are particularly relevant, they will be noted.
2 Analogies and metaphors
Theologians discuss complex concepts about a transcendent domain, while knowledge about that domain is far from complete. This often makes direct, literal language unavailable, inapplicable, or inaccessible to the intended audience. Theologians therefore make use of analogies and metaphors, often drawn from other disciplines.
It is worth pausing over the distinction between analogies, metaphors, and models, since these terms are often used interchangeably. Janet Martin Soskice (1985: 101) has argued that a model involves viewing one thing in terms of its resemblance to another. When such a model is expressed linguistically – for instance, ‘the brain is a computer’ – it becomes what Soskice calls a theory-constitutive metaphor. Such metaphors then generate further theoretical vocabulary derived from the model: terms like ‘programming’, ‘input’, and ‘feedback’. This distinction matters because, on Soskice’s account, metaphorical language in science can describe reality, providing partial access to entities and relations not yet fully understood. The question is whether quantum-theological metaphors refer to real features of the divine or whether they function merely rhetorically.
In ancient times, agricultural imagery was common in theological discourse across traditions. Jesus’ parables frequently use farming analogies (sowing seeds, separating wheat from chaff; see, for instance, Mark 4; Luke 3:17), while monastic traditions often describe spiritual formation as cultivation. The Qur’an compares the growth of faith to a ‘goodly tree, whose root is firmly fixed, and its branches reach to heaven’ (14:24). Economic concepts also frequently appear in theological discourse (cf. Economics, section 5). Salvation is often described using transactional language drawing from the marketplace, such as redemption, ransom, debt forgiveness, and investing in the afterlife. (For more on this theme, refer to Debt and Redemption in Soteriology.)
Quantum mechanics has proven to be quite fruitful in this regard. We begin with the idea of wave-particle duality.
2.1 Duality and Niels Bohr’s complementarity
One might think of light as a wave with properties like frequency and wavelength, and photons as discrete particles that compose that wave. However, this description fundamentally misrepresents the quantum picture. Electrons, which are paradigmatically particles, also exhibit both wavelike and particlelike properties. They interact discretely with photographic film, leaving individual dots upon impact; yet they also produce distinctively wavelike phenomena such as interference patterns.
This wave-particle duality is exemplified in the ‘two-slit experiment’. Electrons are shot through a barrier that has two slitted openings. The film on the far side shows where each electron passing through the slits lands. When the electron is first emitted, it is a particle. That is what the electron gun produces. When it hits the film, it is also a particle with an observable position on the screen. Between the two, however, it displays wavelike characteristics, including the ability to pass through both slits at once and produce constructive and destructive interference (the dark and light areas that emerge from a large number of hits on the screen).
While experiments show that quantum entities can exhibit characteristics of waves (such as interference and diffraction) and also of particles (such as localized interactions), no single experiment can measure both simultaneously (Carroll 2024: 39–41). The choice of measurement apparatus dictates which of the two is detected. Niels Bohr, one of the fathers of quantum theory, described this as one example of ‘quantum complementarity’: some pairs of physical properties of quantum systems cannot be simultaneously observed, but both must be included in the mathematics to produce a complete description of the system (Bohr 1928). Complementarity was uncontroversial as a description of wave-particle duality. But Bohr’s application of the idea expanded throughout the 1930s and 40s to become an overall principle of epistemology, one that garnered more attention than it merited due to his stature (Becker 2018: 38–41).
Duality is paradoxical. Waves are spread out across space. Particles are in a specific place at any given time. It doesn’t seem that a single entity can be both, but that is what the data indicate. Theologians have noted a similar conceptual tension in several theological doctrines. John Polkinghorne believes duality is analogous to the puzzling description of Jesus having two natures, one human and one divine (2007: 16–17, 24, 92–93). The Chalcedonian Creed (451) states that Jesus is fully God (the second person of the Trinity) and fully human. However, Jesus of Nazareth died in the first century. God is immortal and cannot die. Jc Beall (2021) argues that saying a person is both human and divine is a contradiction, one that requires the rejection of classical logic. Polkinghorne argued instead that more nuance is needed (2007: 92–93). In the wave/particle case, a deeper reality is revealed by quantum field theory, which describes particles themselves as manifestations of fields. Once the underlying theory is understood, we see that there is no conceptual tension and certainly no contradiction. Likewise, there may be a way to resolve the God-human relation within Jesus, although we do not have the intellectual capacity to fully grasp it. It is paradoxical from our limited epistemic position but could be resolved if only we understood the full picture.
Other pairs of doctrines are likewise in tension (Russell 1988: 360–363; Russell 2015: 45–47): God’s immanence and transcendence, divine justice and grace, human freedom and providence, and humans as beings of both body and soul. Any sort of deep dichotomy might be a variety of complementarity/duality. If physics, much of which is highly confirmed, must live with irreducible dualities, we should not be surprised to find the same in theology. The evidential bar for physics is far higher, and still the tensions remain. The main objection to such analogies is the concern that they are simply appeals to mystery. Consider the doctrine of the two natures of Christ again. Perhaps the two claims are contradictory, and invoking duality masks the contradiction (MacKay 1974: 225). While we now understand the physics underlying wave-particle duality, there is no guarantee that analogous tensions in theology can be similarly resolved.
2.2 Entanglement and nonlocality
The oddest phenomenon in quantum theory may well be entanglement (Carroll 2024: ch. 3). This is when particles become linked in such a way that they must be described as a single physical system, even when separated by vast distances. Physically and mathematically, entangled particles constitute one system with a single quantum state. Treating the particles as independent of one another yields the wrong predictions.
As a somewhat simplified example, consider a pair of entangled photons, Alpha and Beta, and say that they travel in opposite directions. One of their properties is (linear) polarization, which refers to the orientation of electromagnetic oscillations as they travel through space. If we test each photon by itself with a polarizing filter (vertical or horizontal), the result looks random: half the time it’s vertical, half horizontal. But if both photons are measured using the same kind of filter, the results are always the same: if Alpha is horizontal, Beta is horizontal; if Alpha is vertical, Beta is vertical. If the two tilt their filters to different angles, the match rate changes in a very specific way. The crucial point, supported by Bell’s Theorem (Myrvold, Genovese and Shimony 2024), is that these outcomes are not dictated by the (local) properties of the photons prior to measurement. Under the standard Copenhagen Interpretation, the travelling photons do not possess a specific polarization. Instead, they exist in an entangled, nonseparable state. Consequently, the measurement of Alpha does not ‘signal’ Beta, but rather instantaneously collapses the single wave function governing both, ensuring their properties are perfectly coordinated across a distance.
The fact that the measurement of one particle has simultaneous consequences for the other no matter how far apart they are means that entanglement involves nonlocal interactions (Albert 1994: ch. 3; Polkinghorne 2010: 6–7). Locality is the idea that an object is directly influenced only by its immediate surroundings. In local systems, there can be no action-at-a-distance, whereby one object influences another without any connection between them. While the influences of a magnet on iron filings might appear nonlocal, there is a field between the two mediating their interaction. In contrast, the influence of one entangled particle on another is genuinely nonlocal. Measurement of Alpha puts immediate constraints on measurement of Beta, even if the two are separated by light-years. This influence, however, is not causal in that Alpha cannot be manipulated in order to send a message to Beta. Any attempt to do so would destroy the entanglement relation.
Nonlocality runs contrary to our typically classical intuitions, and it is worth noting that not all interpretations of quantum mechanics accept it. It was the apparent lack of locality in quantum mechanics, not its indeterminism, that caused Albert Einstein to believe that the theory was incomplete (Becker 2018: 51).
One theological analogy that has been drawn with entanglement is the Buddhist notion of interdependence (pratītyasamutpāda, dependent arising) (Ricard and Thuan 2001: 68–69). On this doctrine, nothing exists on its own and all phenomena arise in dependence upon others. Things are not autonomous entities that precede their relations. Their very being consists in their relationships.
Another analogy has to do with the doctrine of the Trinity. According to the First Council of Constantinople (381), the Trinity involves two claims. First, there is only one God. Any sort of polytheism is rejected. Second, there are three distinct divine persons (hypostaseis in Greek, personae in Latin): the Father, the Son, and the Holy Spirit. While the Trinity is subject to a variety of interpretations (Tuggy 2025b), they tend to emphasize one of these claims at the expense of the other (Polkinghorne 2007: 101–102). For example, modalism takes the Father, Son, and Holy Spirit to be different modes, roles, or manifestations through which the single divine person reveals himself or acts in history. Modalism denies the credal claim that there are multiple persons within the Godhead, preserving monotheism but not the distinctness of the three persons. Arianism, in contrast, holds that there is an essential or ontological inferiority of the Son to the Father (Tuggy 2025a: section 3.2). It implies that the Son is not fully equal in divine essence with the Father. The view upholds the individuation of persons in the Trinity but is in tension with absolute monotheism. Simply put, there appear to be three gods, not one.
Some believe that entangled particles are analogous (Wegter-McNelly 2011: section 6.1). There is distinctness – we can talk coherently about Alpha or Beta, for example – but there is also indivisibility. In a quantum system, entanglement shows how particles that seem to be separate entities have an underlying wholeness. According to the analogy, the individual persons within the Trinity are likewise fundamentally distinct and yet are simultaneously indivisible in their essential nature and relational dynamics. Again, if such a relation is found in physics, then a similar one in theology is not sui generis.
One might worry, however, that the analogy is drawn too quickly: entanglement is mysterious and the Trinity is mysterious; are they the same sort of mystery? Whether they are or not is difficult to say. It may be that entanglement sheds some light on the Trinity, but such an appeal may simply create a permission structure to live with a contradiction rather than being forced to articulate a more precise (and perhaps more controversial) position.
There is a second analogous relation with entanglement to be considered. If I create a work of art, I am distinct from the artwork. God is commonly taken to be both Creator and immanent/omnipresent in the work of God’s creation (Wierenga 2023).
Where can I go to escape Your Spirit? Where can I flee from Your presence? If I ascend to the heavens, You are there; if I make my bed in Sheol, You are there. If I rise on the wings of the dawn, if I settle by the farthest sea, even there Your hand will guide me; Your right hand will hold me fast. (Ps 139:7–10)
He is with you wherever you are. (Qur’an 57:4)
Omnipresence is a straightforward matter for pantheism, which takes God and nature to be coextensive. It is harder for traditional monotheism to make sense of both immanence and transcendence. Panentheism lies somewhere between the two, maintaining that while everything is in God, God is more than the world.
The question has roots in classical mechanics. Isaac Newton famously drew an analogy between absolute space and the ‘sensorium’ of God (Opticks, Query 28). This suggests that God perceives all things within space directly and immediately, much like we perceive mental images (Leibniz and Clarke 1956: 21–22; first published 1717).
Nonlocality and entanglement provide more recent analogies for how God can be both present and transcendent:
Quantum entanglement, understood through the lens of relational holism, can broaden and deepen our awareness of the world’s relationality by helping us to appreciate more deeply the unfathomable interdependence, ubiquitous relationality, and immeasurable reciprocity of the universe. (Wegter-McNelly 2011: 134)
Much as Beta is intimately related to Alpha, even at a distance, God can be related to every aspect of nature without having an observable presence. If God is in some sense entangled with creation, then God can remain both transcendent Creator and immanently present within that creation.
More traditional theists may object that such a relation is far too close to maintain the creator–creation distinction. God and nature are not one system. Panentheists, in contrast, will have no such objection (Simmons 2014: 153–157).
One final concern is that the physical details of entanglement make it less apt as an analogy than it appears at first glance. Entanglement does not characterize every object in the universe at all times. While in the standard interpretation of quantum mechanics ‘measurement’ is a vague term, it includes the interaction of quantum systems with human agents. Among the effects of a measurement are the collapse of the wave function (more on this in section 4.2) and breaking of entanglement (Barrett 2001: 22–30). That is not what theologians using this analogy claim. Neither God’s transcendence nor immanence ‘collapses’ from time to time. Hence, the analogy can only be pressed so far.
3 Quantum mechanics and epistemology
Critics of religion often contrast the empirical basis of science with the speculative nature of theology. Science, they argue, deals with observable phenomena and testable hypotheses, while religious claims are beyond empirical verification (for more detail on this tension, see Theology and Naturalism). But quantum mechanics introduces new limits to scientific knowledge that complicate this stark (and overly simplistic) dichotomy. These limits are most readily apparent in Heisenberg’s uncertainty principle. The principle states that it is impossible to simultaneously know the precise values of specific pairs of properties, e.g. the exact position and momentum of a particle. The more precisely one of these properties is measured, the less precisely the other can be determined. The uncertainty principle represents a new, fundamental feature of quantum mechanics. No matter what technological breakthroughs come to pass, the principle cannot be circumvented.
This was not the case in classical mechanics. Any imprecision about a particle’s position or momentum was thought to be due strictly to the limitations of the experimentalist’s instruments or techniques. There is no theoretical reason in classical physics why all atomic properties cannot be known with arbitrary precision.
Traditional theological responses to our limited epistemic access to the divine vary. Apophatism is one end of the spectrum. While all theists believe that God is to some extent beyond our understanding (Isa 55:8–9), strict apophatism says that knowledge of the divine can only come via negativa, that is, we can at most say what God is not (e.g. God is not corporeal; the divine is not temporal). In Christian theology, Pseudo-Dionysius’ Mystical Theology (c. 500) is a key example of such a position (Pseudo-Dionysius the Areopagite 1987).
Some make the connection between the epistemological limits in theology and quantum mechanics explicit, arguing that ‘quantum mechanics seems to contain its own apophatic element’ (Mooney 1993: 384). Stoeger (2001) repeatedly refers to our ‘veiled reality’, which applies to both quantum phenomena and to everything that God does to some degree or other. At the very least, our limited access to God should promote a strong sense of epistemic humility among theologians and philosophers of religion (Bondi 2024: section 3).
While it is universally acknowledged that quantum phenomena present difficulties that classical mechanics did not, one must take care in drawing lessons from Heisenberg’s uncertainty principle. The name itself is misleading. While ‘uncertainty’ sounds epistemic, the concept is not (Padgett 2009: 179). What it actually refers to is the fact that some pairs of quantities do not have precise values (Lewis 2016: ch. 4). There is no fact-of-the-matter to be known about such quantities. By analogy, that you do not know the name of the present king of Poland is not due to a lack of knowledge on your part. It is because Poland does not have a king. Likewise, there is no precise truth about position and momentum that is somehow hidden from experimentalists. The intrinsic fuzziness of these quantities is more aptly referred to as ‘indeterminacy’, rather than ‘uncertainty’.
Unfortunately, ‘indeterminacy’ itself is often conflated with ‘indeterminism’, which is a distinct concept. Indeterminacy refers to quantities that do not have precise or determinate values. Determinism says that from a given state, a system will evolve according to the laws of nature in precisely one way. Each state of the system has its own unique evolution over time. Indeterminism is a denial of this: the state of a system at a given time plus the laws of nature do not determine a unique outcome. This will be an important idea in section 5.
Taken ontologically, indeterminacy is about the intrinsic imprecision of properties like momentum at a point in time. It is not that there is an actual value that we cannot detect. There is no precise value. In terms of the epistemology of science, Heisenberg uncertainty shows that some questions we might wish to pose in physics, ones that make perfect sense from a classical point of view, have no answer from a quantum mechanical point of view. Forcing nature to answer questions in familiar, classical terms only leads to confusion.
Similarly, there are theological questions we might want to pose for which there are no determinate answers. God is transcendent and to some degree incomprehensible. We should be careful not to demand that answers to every theological question fit within the categories that make sense from our point of view (Polkinghorne 2004: 77).
4 Quantum cosmology
4.1 Creation ex nihilo
While the doctrine of creation ex nihilo has biblical support (2 Mac 7:28; Heb 11:3), it was first articulated in the second century CE in opposition to Greek philosophical views of an eternally existing universe. The doctrine denies both that physical reality was organized from preexisting material and that it is an unconscious emanation from a divine substance. Creation ex nihilo instead emphasizes both divine omnipotence and the absolute contingency of the created world. It is one answer to the longstanding philosophical question about why physical reality exists rather than nothing at all.
Several research programs in quantum cosmology suggest that physics now has the resources to provide its own answers. Quantum fluctuations can look very much like the appearance of something from nothing. Applying the concept to the universe itself was first proposed in a two-page paper in the journal Nature (Tryon 1973). It begins with the idea of a quantum ‘vacuum state’, in which there are no particles. Heisenberg’s uncertainty principle allows for random fluctuations in energy, typically in the form of so-called ‘virtual particles’ (matter/antimatter pairs). Edward P. Tryon posited that an unusually large quantum fluctuation could produce the beginning of an expanding universe: the Big Bang was a fundamentally quantum event.
This idea was developed by Alexander Vilenkin using the phenomenon of quantum tunnelling (1982; 2006). In the quantum world, particles sometimes pass through barriers even when those particles do not have the energy to overcome such barriers. For example, consider an electron gun pointed at a mountain. The momentum imparted to an individual electron is not nearly enough to launch it over this obstacle. From time to time, however, the particle will simply appear on the other side of the mountain, apparently tunnelling through. Vilenkin applied this idea to the origin of the universe (technically to its scale factor or overall size). From a quantum vacuum state with no space, time, matter, or energy, an entire spacetime tunnels into existence.
Other proposals allow for a universe that comes into being without a clear beginning in time. James Hartle and Stephen Hawking’s ‘no boundary’ model says that at a point very close to the Big Bang, time was not linear (Hartle and Hawking 1983; Hawking 1988: 135–141). It was instead complex (in the mathematical sense), having both a real component and an imaginary one – more like a sphere than a line. (Note that the terms here are not intuitive: there is nothing imaginary about imaginary numbers.) For our purposes, the key is that the material, temporal universe of our experience simply comes into being.
Physicist Lawrence Krauss (2012) argues that these scenarios provide naturalistic alternatives to creation ex nihilo. There is no need for a creator if the universe can spontaneously emerge. Hawking made similar remarks:
The idea that space and time may form a closed surface without boundary also has profound implications for the role of God in the affairs of the universe. […] So long as the universe had a beginning, we could suppose it had a creator. But if the universe is really completely self-contained, having no boundary or edge, it would have neither beginning nor end: it would simply be. What place, then, for a creator? (Hawking 1988: 140–141)
Physics seems to have removed the need for a miraculous creation.
Such claims are, however, philosophically naive. The fundamental problem is that the quantum vacuum is not ‘nothing’ (Albert 2012). Each quantum cosmological proposal mentioned here begins by assuming a universal wave function that describes a pre-material state. However, none of them explain where the wave function itself comes from. Consider Vilenkin’s tunnelling proposal. Even if we grant that it correctly describes how spacetime and matter emerge, we still need an explanation for the quantum fields that undergo tunnelling in the first place. If the explanatory story begins by presupposing the existence of quantum fields and their associated laws of nature, then they have not explained creation ex nihilo in any meaningful sense (Stoeger 2010).
These proposals conflate two distinct questions: (i) how did space-time and ordinary matter begin? and (ii) why does anything exist at all? At best, quantum cosmological models address the first question while leaving the second untouched. They show how material entities might emerge from quantum processes, but they cannot explain the ontological origin of those processes themselves. The quantum vacuum, with its fields and fluctuations, is already ‘something’ rather than ‘nothing’. Any explanation that starts there has simply pushed the ultimate question of existence back one step rather than answering it.
4.2 Many-worlds interpretation
Up to this point, there has been no need to distinguish between different interpretations of quantum mechanics. All the phenomena mentioned so far can be accommodated by each of them with slight adjustments. Discussions of quantum mechanics, including this one, are typically couched in terms of the Copenhagen Interpretation. The idea that there ever was such a single, unified position by this name, however, is false from a historical point of view (Becker 2018: 49; Harris 2023: 189). The view that many now think of as the Copenhagen Interpretation was most clearly formulated by John von Neumann (1955; first published 1932), who gives a mathematical description of two distinct evolutions. First, there is the normal quantum state changing over time according to Erwin Schrödinger’s wave equation. It describes, for example, how the state of the electron evolves in the two-slit experiment between its source and the photographic plate. Such changes of state are completely deterministic. Second, there is the probabilistic ‘collapse’ of the wave function during a measurement, like the individual dots produced on the film in the two-slit experiment. This second process is indeterministic. Only the probability of any given outcome can be inferred, via the Born rule, from the quantum state as it evolves according to the Schrödinger equation.
From the beginning, there was a persistent vagueness about what counts as a ‘measurement’. According to some, like Eugene Wigner (1961, republished 1983), measurements are performed by conscious beings. Hence, consciousness is a necessary condition for a measurement event. In other interpretations of quantum mechanics, such as Ghirardi–Rimini–Weber (GRW), the collapse of the wave function happens spontaneously rather than by measurement (Lewis 2016: section 3.2). Every interpretation with a collapsing wave function is at least in part indeterministic. Other interpretations preserve determinism. According to Bohmian mechanics, for example, particles possess definite positions at all times and are guided by a ‘pilot wave’ that is responsible for their wavelike behaviour (Albert 1994: ch. 7; Maudlin 2019: ch. 5).
The many-worlds interpretation is also deterministic. It says that whenever a collapse of the wave function would have happened under the standard interpretation of quantum mechanics, each possible outcome of a measurement event actually occurs in its own universe. This interpretation is sometimes called ‘Everettian’ after Hugh Everett, who first proposed its underlying mathematics in an unpublished draft of his doctoral dissertation (Everett 1957; Becker 2018: 127). Bryce DeWitt (1970) later introduced the idea of splitting worlds or universes.
Consider how this works in the famous Schrödinger’s cat thought experiment. The device in the room along with the cat amplifies quantum effects into the macroscopic realm. One of these effects is known as superposition, in which distinct classical states are held at the same time. The way the experiment is set up, there are two such classical outcomes: the cat is either dead or alive. Prior to a measurement, the cat remains in a superposition of both states. In the Copenhagen Interpretation, once someone looks into the room, a measurement has been made, the wave function collapses, and superposition is destroyed, leaving one classical state: cat dead or alive. In the many-worlds interpretation, in contrast, a measurement event does not cause a collapse of wave function. Instead, the different possible outcomes all occur, but within their own newly-created universes – hence ‘many worlds’. (More recent formulations of this interpretation speak of ‘branches’ within one global wave function, rather than separate ‘worlds’; see Wallace 2012.) In one such universe, the cat lives, in another it dies, with everything else remaining the same. This means that over time there will be a large, perhaps infinite, number of copies of each one of us across the quantum multiverse.
Theologically, this presents at least two problems. First, an Everettian multiverse threatens to make the problem of evil far more challenging (Mann 2015; Lougheed 2015: 484; Qureshi-Hurst 2023). Such a multiverse would contain worlds in which there are far worse kinds of evil than in our own. Some would be truly dystopian universes featuring not just more instances of familiar evils but suffering of a fundamentally different character and magnitude, ‘worlds in which the emergence of the human race proves to be an unmitigated tragedy’ (Zimmerman 2017). Against such scenarios, standard theodicies appealing to free will and the like appear woefully inadequate. The conceptual resources available to theists seem insufficient to explain how an omnipotent, omniscient, and perfectly good deity could permit the actualization of such worlds.
A second theological problem has to do with God’s relation to one’s counterparts in other universes. Could seventy percent of them go on to a happy afterlife, and the other thirty percent be damned? If the difference between the two is merely a matter of one’s contingent circumstances, that would seem to introduce a significant component of luck into the question of salvation (Zagzebski 1994). Moreover, as Emily Qureshi-Hurst asks, what happens in those universes that lack some key figure, such as Jesus of Nazareth or Muhammad? The very possibility might be a reason to believe in universalism, the view that all people can achieve salvation regardless of their specific religious beliefs (Qureshi-Hurst 2023: 240–243).
One theistic response is to take these compounding theological problems as reasons to reject the many-worlds interpretation. After all, other interpretations are available, many of which are more popular among physicists (Gibney 2025). If, on the other hand, the many-worlds interpretation is correct, theism has ways of addressing the problem.
One is that God destroys those branches/worlds that would lead to unacceptably evil universes. Another involves adding a mechanism so that not all worlds are ontologically on a par. Perhaps, as philosophers of physics David Albert and Barry Loewer first suggested (Albert and Loewer 1988), persons have minds, but minds do not undergo Everettian splitting. Minds are understood here in some sort of dualistic sense in which they are related but not identical to the brain. Given that Everettian splitting is a physical process, there is no reason to believe that process will necessarily affect immaterial minds. If not, then there will be many branches that contain physical replicas of people, but most will be mindless husks (what the philosophy of mind literature refers to as ‘zombies’) rather than persons. If all minds travel along the same branch together, then there is only one branch at any instant that contains minds and therefore, on a dualist view of personhood, only one branch with people (Barrett 2001: 191; Pruss 2014). (Robert Koons gives an Aristotelian variant of this idea: only one branch contains substantial forms/essences [2017].)
The bottom line for this family of views is that, even if a quantum multiverse exists, it only contains one universe – this one – with beings capable of experiencing suffering. Moreover, there is only one with persons in need of repentance, salvation, or grace.
5 Indeterminism and divine action
One theological application of quantum mechanics has gotten more attention than the rest in recent decades: the question of special divine action. ‘General divine action’ refers to God’s overall upholding of the universe in existence and maintaining its order. ‘Special divine action’ encompasses all of the other interactions God has with nature (Ps 107:21). A question about special divine action has to do with divine intervention in the natural order. Once the idea that there are laws of nature ordained by God took hold in the early modern period, theologians and philosophers began to question whether God would break or suspend those laws from time to time. Some, like Isaac Newton, seemed to think so. Others, like Gottfried Wilhelm Leibniz, did not (Leibniz and Clarke 1956: 11–12; first published 1717). Leibniz took intervention to be the act of a lesser god who lacked the foresight to get things right in the first place. Even apparently miraculous violations, he thought, are in accord with the most general laws used for regulating the course of nature (Leibniz 1991: section 7; first published 1686).
Another worry about interventionist special divine action is that it would make God inconsistent, as Arthur Peacocke argued:
The very notion of God as the faithful source of rationality and regularity in the created order appears to be undermined if one simultaneously wishes to depict his action as both sustaining the ‘laws of nature’ that express his divine will for creation and at the same time intervening to act in ways abrogating these very laws—almost as if he had second thoughts about whether he can achieve his purposes in what he has created. (Peacocke 1993: 142, original emphasis)
Violating the very laws of nature that God had chosen would entail a conflict within the divine will (Russell 2008b: 584). This is a fundamental concern among theologians working on special divine action today.
Finally, many believe that divine interventions conflict with modern science. As David Friedrich Strauss wrote in his Life of Jesus (1835), a scientific worldview shows that ‘[a]ll things are linked together by a chain of causes and effects, which suffer no interruption’ (Brooke 1991: 270–271). Philip Clayton gives a more recent elaboration on the idea:
Physical science, it appears, leaves no place for divine action. To do science is generally to presuppose that the universe is a closed physical system, that interactions are regular and lawlike, that all causal histories can be traced. […] Unfortunately, the traditional way of asserting that God acts in the world conflicts with all four of these conditions. (Clayton 2008: 186)
As John Macquarrie (1977: 248) puts it, a theology that allows for divine intervention in the natural order is directly at odds with science.
Concerns over interventionist special divine action have prompted two reactions, both of which are called noninterventionism in the theology and science literature (though they should not be confused for one another). The first is to reject all forms of special divine action. While deism may be considered an extreme form of this, some theologians such as Langdon Gilkey support such a view:
Thus contemporary theology does not expect […] wondrous divine events on the surface of natural and historical life. The causal nexus in space and time which the Enlightenment science and philosophy introduced into the Western mind […] is also assumed by modern theologians and scholars; since they participate in the modern world of science both intellectually and existentially, they can scarcely do anything else. […] Suddenly a vast panoply of divine deeds and events recorded in scripture are no longer regarded as having actually happened. […] Whatever the Hebrews believed, we believe that the biblical people lived in the same causal continuum of space and time in which we live, and so one in which no divine wonders transpired and no divine voices were heard. (Gilkey 1961: 31)
Gilkey and others take all forms of intervention to be theologically suspect.
The second reaction takes strict noninterventionism to be too extreme. The issue is not, according to this position, God’s direct action in nature but those types of interventions that violate the laws of nature. Nonviolationism is the thesis that God can influence or interact with nature in any way that does not break its laws (Koperski 2020: section 1.1).
To see what quantum mechanics allows, consider a familiar narrative that, before quantum mechanics, nature was taken to be a completely closed, deterministic system (Russell 2008b: 580; Wegter-McNelly 2008: 162). (The actual history is more complicated; see Koperski 2026: ch. 3.) In such a world, the only sort of randomness allowed is epistemic, reflecting a lack of knowledge on our part. For example, we think of a coin toss or rolling dice as random, but if we knew the linear and angular momentum imparted to such systems, we could calculate how they will land according to the laws of mechanics. We don’t have access to that data and couldn’t do the calculations quickly enough even if we did. But a super intelligence, as envisioned by Pierre-Simon Laplace (1902; first published 1814), with unlimited computational capacity and infinitely precise measurements, could predict the future state of all classical systems of particles.
In contrast to epistemic randomness, the Copenhagen Interpretation of quantum mechanics involves ontologically random events. Ontological randomness corresponds to what philosophers of science and physicists call ‘indeterminism’, whereby the laws of nature do not specify a unique outcome to some events. Consider radioactive decay. Nuclides such as uranium decay over time, but if one asks when a particular nucleus will decay, there is no determinate answer. Radioactive decay is intrinsically random – there is no hidden trigger that initiates the process. According to the relevant laws of nature, there is no exact moment at which a given atom will decay. The best physics can offer is the probability of decay within a given interval, nothing more. Wave function collapse likewise involves ontological randomness. There is no physical fact of the matter that causes, say, the Schrödinger’s cat experiment to turn out one way rather than the other.
Marshalling ontological randomness in the service of special divine action, the core idea is that those indeterministic quantum events are in fact determined by God. The thesis goes back at least as far as William Pollard (1958) and has been supported to some degree or other by Thomas Tracy (1995), Nancey Murphy (1995), George Ellis (2001), and most prominently Robert J. Russell:
If I adopt the interpretation that these quantum statistics reflect ontological indeterminism, then I may argue that God can act together with nature to bring about all events at the quantum level, and that these events give rise to the classical world. (Russell 2002)
(For related ideas in an Islamic context, see Guessoum 2016: section 3 and Altaie 2016: ch. 4.) In short, God exercises causal influence within the space of ontologically random quantum possibilities without violating the laws of nature. In the case of Schrödinger’s cat, should God want the cat to live, God need not break any laws to achieve this end. Rather, God operates within the indeterministic framework of quantum mechanics, selecting from among physically possible outcomes. Quantum randomness provides a causal joint through which God can influence nature. God determines which quantum possibility becomes actual from among those permitted by the wave function’s evolution.
Russell calls his model QM-NIODA, for ‘quantum mechanical noninterventionist objective divine action’. It is objective in the sense that it is mind-independent: God acts in nature. Calling it noninterventionist, however, is misleading. God does intervene on this view, but in a way that does not violate the laws of nature. It is instead a nonviolationist model of divine action. Under QM-NIODA, nature only provides the necessary conditions for the outcome of quantum events. God takes the role of a nonphysical ‘hidden variable’ that determines their precise outcome (Russell 2008a: 157; Russell 2009). As Murphy puts it, ‘God’s governance at the quantum level consists in activating or actualizing one or other of the quantum entity’s innate powers at particular instants’ (1995: 342). It is important to note that by ‘quantum event’, Russell et al. mean a collapse of the wave function.
Critics have three main objections. The first is that there are interpretations of quantum mechanics in which the wave function never collapses. Among them are the Bohmian and many-worlds interpretations mentioned previously. If there is no collapse of the wave function, then there are no ontologically random events in quantum mechanics for God to determine. The necessary conditions for QM-NIODA would not be met.
Second, some argue that the model is in fact highly interventionist (Saunders 2000). If God acts in nature every moment throughout the universe to determine the outcome of physical events, that would be as interventionist as one could imagine.
Third, quantum events seldom make a difference in the macroscopic realm. In order for divine action at the quantum level to register in our everyday experience, those events would need to be amplified in some way (Guessoum 2011: 337). Murphy argues instead that quantum events can have macroscopic effects by sheer accumulation (1995: 356–357). While the effects of quantum events are small, they can add up in order to influence the macroscopic realm.
Unfortunately, Murphy’s solution misrepresents the nature of the events in question, which do not accumulate like sand or snowflakes. By analogy, say that you want to throw a rock across Lake Huron. You can throw as many rocks as you want, but since you cannot impart sufficient kinetic energy to any one of them, none will reach the other shore. The number of rocks you throw is irrelevant. Likewise, the number of quantum events has nothing to do with whether those events have macroscopic effects.
One mechanism for amplifying quantum randomness is genetic mutation (Ellis 2001: 260). Point mutations can be produced by radiation, and radiation from nuclear material involves quantum events. A sufficient number of mutations could, in turn, affect the evolution of a species. QM-NIODA-controlled radiation could therefore be a mechanism for theistic evolution. (See Qureshi-Hurst and Bennett 2021: 83 for difficulties surrounding this proposal.)
Some have looked to chaos theory as another amplifier of quantum events (Murphy 1995: 349–349; Tracy 1995: 317–318; Clayton 1997: 196; Guessoum 2011: 338). Chaotic systems display sensitive dependence on initial conditions: minute changes to a system’s state can yield large downstream effects. This is what is commonly called the ‘butterfly effect’. Applied to Earth’s atmosphere, the metaphor suggests that something as small as a butterfly’s movement in Japan could in time have cascading effects so that what would have been a clear day over Miami next year becomes a hurricane. The idea, then, is that God’s making changes at the quantum level is something like the butterfly. Tiny effects at the quantum level can bring about large-scale changes within a chaotic system.
A more complete understanding of chaos theory, however, undermines the idea that sensitive dependence on initial conditions amplifies quantum events (Koperski 2020: section 3.2). One problem is that while chaotic systems are all around us, their effects are generally quite weak (Ruelle 1994). To take one example, mammalian heartbeats are chaotic, but negligibly so. Sophisticated time-series analysis is needed to detect chaos in predominantly regular heartbeats. So while chaos is found throughout nature, it is typically hard to detect. For chaos to serve as an effective amplifier of quantum special divine action, its effects would need to be more prevalent in observable systems, rather than being a kind of background noise.
Physicist-theologian John Polkinghorne held a related but distinct view of special divine action. Polkinghorne took quantum indeterminism and Heisenberg uncertainty to be indicators that the physical world is open to divine influence (2003: ch. 3). He did not believe, however, that the precise nature of this influence was currently known.
While Russell and others frame the issue of divine action within indeterministic processes, Basil Altaie (2016) develops a comparable account in Islam: quantum openness is not mere chance but a metaphysical opening for God’s perpetual re-creative governance.
6 Consciousness and theological anthropology
Another intriguing idea is that quantum mechanics is needed to understand consciousness and human nature. The relevance is not immediately obvious: quantum phenomena occur at microscopic scales, while the brain is a macroscopic organ. Nonetheless, several proposals attempt to connect the two. This section examines the most significant of these, focusing on the idea that quantum mechanics supports a nonreductionist understanding of the mind.
As discussed in section 4.2, the notion of ‘measurement’ is controversial in quantum mechanics. In the Copenhagen Interpretation, systems in superposition do not have definite, classical states until they are measured. Precisely what constitutes a measurement, however, remains contested. Eugene Wigner proposed a striking answer. Conscious experiences are determinate by their very nature. There is no superposition of mental states. Wigner (1983) argued that measurement is an act performed by conscious beings. Systems in superposition remain that way until a conscious observer interacts with them. But if consciousness is required to bring about definite outcomes from superposition, then it cannot be reduced to the physical processes described by quantum mechanics alone. Consciousness would seem to be a part of reality on a par with quantum mechanics itself.
While this anti-reductionist conclusion is defensible (Clayton 2004), Wigner’s own proposal was never widely embraced and has no well-regarded defenders among physicists or philosophers of physics today. The main objection is that it explains one mystery by invoking another. What exactly is a ‘conscious observer’, and why should consciousness interact with physical systems in this way?
This does not mean, however, that quantum mechanics has nothing to contribute to debates about consciousness. Hans Halvorson (2011) argues that the more extravagant interpretations of quantum mechanics are driven in part by physicalist assumptions about minds. If one assumes that consciousness must be explained by physics, then the failure of quantum mechanics to do so becomes a puzzle that pushes theorists into exotic solutions. If one instead takes mind-body dualism as a theoretical posit, then the inability of quantum mechanics to explain consciousness is simply a matter of its limited scope. Physical theories describe physical phenomena; they need not explain nonphysical properties like subjective experience. On Halvorson’s view, the explanatory gap is exactly what one would expect.
The theological relevance of this debate lies in its implications for human nature. Traditional theological anthropology holds that human beings are not merely physical entities. While quantum mechanics does not establish such a view, as Halvorson’s argument shows, it does not preclude one. Neither reductionism nor physicalism are entailed by quantum physics.
7 Looking ahead
One obstacle to drawing theological lessons from quantum mechanics is the theory’s different interpretations. Theologians tend to approach physics as scientific realists, believing that mature theories reveal the truth about reality, or at least approximately so. But as Mark Harris (2023: 184) points out, Bohr’s pioneering work tended toward anti-realism: between concrete measurements, quantum mechanics tells us nothing about the micro-realm. Bohr believed that quantum mechanics allows probabilistic predictions about macroscopic observations but is silent about the nature of the quantum world. Strictly speaking, he did not believe in an unobservable quantum realm: only macroscopic events, like the results of experiments, are fully real.
This anti-realism was another indication for Einstein that quantum mechanics is an incomplete theory. He believed that physics should provide insight into the nature of reality, not merely facilitate predictions about indeterminate quantities. Nonetheless, some more recent interpretations lean more toward Bohr’s anti-realism than Einstein’s realism. For example, Quantum Bayesianism (QBism) does not take quantum mechanics to be describing an agent-independent reality. Instead, the theory provides a framework for agents to update their subjective degrees of belief (credences) about the outcomes of measurements. On this view, quantum states are not features of the physical world but tools that individual agents use to make predictions based on their experiences. The wave function represents an agent’s state of knowledge rather than an objective property of a quantum system (Ball 2018: 120–123). If this is right, then quantum mechanics tells us nothing about the deep structure of physical reality but merely codifies how agents should revise their expectations. For our purposes, the upshot is this: if any of the more anti-realist interpretations is correct, then quantum mechanics would be much less useful to theologians.
Let’s say that one instead adopts a more realist approach. There is still a fundamental division between those interpretations that involve a collapse of the wave function and those that do not. Theologians are most familiar with the Copenhagen Interpretation, which is in fact a family of views. What these views have in common is an irreconcilable discontinuity between the unobservable, purely quantum mechanical physics governed by Schrödinger’s equation and the probabilistic outcomes brought about by the collapse of the wave function. While this is often thought of as orthodox quantum mechanics, it is difficult to find defenders of Copenhagen among physicists specializing in foundations or philosophers of physics.
Non-collapse interpretations reject the idea that there are special events – measurements – to which Schrödinger’s equation fails to apply. There is no indeterminism in physics on these accounts, making them incompatible with most of the work relating quantum mechanics to divine action in the last thirty years. These differences between interpretations means there is no one body of knowledge known as ‘quantum mechanics’ available to the theologian. The lessons drawn from one interpretation may not apply in another.
Another question in terms of the theology of nature is how central quantum mechanics should be. There are currently two broad answers. The first is what Harris (2023) calls ‘quantum fundamentalism’. Everything in the universe is essentially quantum and ultimately describable by quantum mechanics, Harris argues, and so the theory has ramifications for all areas of natural science, from particle physics to chemistry and biology. Any sort of creation theology that addresses the physical universe as a whole must therefore inevitably be tied to quantum mechanics.
The second answer is based on emergence (Clayton 2006). A metaphysical understanding of emergence says that higher levels of physical reality – chemical, biological – are just as real as fundamental physics (Bishop, Silberstein and Pexton 2022; Koperski 2026: chs 7–8). Emergentists deny that quantum mechanics, or more broadly the Standard Model of particle physics, can account for all the truths of condensed matter physics, let alone those in other natural sciences. While fundamental physics is interesting and important, it is not singularly so, as evidenced by the continued fragmentation of the sciences and the failure to reduce higher levels to lower ones.
The two strategies are grounded in different ontologies of nature. Quantum fundamentalism is aligned with the assumptions of many physicists, who tacitly assume a quantum-first picture. Theology that engages quantum foundations, one might argue, is therefore better positioned to dialogue with contemporary science. Emergentists, on the other hand, worry that such an approach tacitly accepts a reductionist framework that theologians are generally opposed to. Consciousness, moral agency, and free will are genuinely emergent properties. An overemphasis on fundamental physics risks limiting natural theology to the concepts of particle physics, potentially obscuring the richness of creation at higher levels of organization.
8 Conclusion
The intersection of quantum mechanics and theology continues to generate both insights and difficulties. Quantum phenomena have proven useful for analogical reasoning and have opened new possibilities for theories of divine action, but fundamental questions remain unsettled. It is unclear which interpretation of quantum mechanics is correct, whether collapse interpretations can survive philosophical scrutiny, and whether quantum indeterminism provides genuine openings for divine action without violating natural law. Theologians must also decide how to balance insights from fundamental physics with the reality of emergent phenomena at higher levels of organization. What does seem clear is that quantum mechanics has permanently altered the landscape for natural theology. The mechanistic, deterministic universe of classical physics no longer constrains theological thinking in the way it once did. Whether this represents genuine progress or merely a shift in the terms of perennial debates remains to be seen.
