What can science tell us about the immense mystery that surrounds us? To what extent can science reveal that reality is not at all what it may appear to us humans in the midst of our everyday practices? Can the science of very small quantum and large cosmic scales provide a new foundation for social sciences too? In this essay, I review and employ two recent books to explore these questions.
Rovelli, Carlo. 2016. Reality is Not What It Seems. The Journey to Quantum Gravity. Trans. by S.Carnell & E.Segre. London: Allen Lane.
Wendt, Alexander. 2015. Quantum Mind and Social Science. Unifying Physical and Social Ontology. Cambridge: Cambridge University Press.
Italian physicist Carlo Rovelli is the author of the bestseller Seven Brief Lessons on Physics that has been translated into some 40 languages; and Alexander Wendt is one of the best known International Relations (IR) theorists. Rovelli’s Reality is Not What It Seems and Wendt’s Quantum Mind and Social Science are two very different books, written for different audiences and with different purposes in mind, but it is useful to read them side by side. Rovelli’s book can be found at the airport bookshops and is an Amazon bestseller, whereas Quantum Mind and Social Science is meant for academics in IR and in social sciences more generally.
Rovelli tells stories and popularizes quantum theory (QT), and in so doing he argues that time and space do not exist; whereas Wendt makes an argument for panpsychism and for seeing human beings as walking wave functions. In what follows, I discuss these apparently rather radical claims in the context of wider philosophical debates about reality and our knowledge about it. Moreover, I am also interested in teasing out the ethics and politics of different readings of QT and its possible wider implications. As Rovelli stresses, the process of science “intersects with the game of power and is affected by every sort of social and cultural influence” (p.184).
In the first part of this review essay, I focus on Rovelli’s book and loop quantum gravity that has taken some preliminary steps toward unifying relativity and QT. In the second part, to be published in a few days, I discuss Wendt’s quantum mind thesis and whether it can really provide a new foundation for social sciences.[i]
Reality is Not What It Seems?
Rovelli’s book is beautifully written: “All of this takes us to the edge of what we know, to the vantage point from which we look upon what we definitely don’t know, the immense mystery that surrounds us.” (p.173) The book is made lively by stories that combine human interest with accounts of advances in science. Rovelli’s great hero seems to be Democritus (c. 460 – c. 370 BC), who is associated with the doctrine of atomism. Rovelli highlights Democritus’ modern understanding of space (in reality fairly little is known of Democritus’ ideas as all his texts have been lost).
Mostly, Rovelli’s overall tale accords with the conventional Eurocentric story about the progress of modern science, built on the basis of “the majestic cathedral of ancient atomism” (p.7), going through the Copernican revolution, and ending in the on-going project of unifying the general theory of relativity and quantum mechanics. But this story includes some less familiar, captivating details. For one, already Dante (c. 1265 – 1321) managed to describe a 3-sphere – “appearing to be enclosed by those that it encloses” – which is a possible contemporary scientific understanding of the geometry of the universe. A finite but immensely large universe without boundaries, like the surface of a 4-dimensional “sphere”. We may find this geometry difficult to visualise, but Dante described it already in his Divina Commedia (1320).
Another fascinating substory is about Einstein giving a weekly lecture on general relativity in Berlin in late 1915, during the First World War, “each time presenting a different equation, anxious that Hilbert would not get to the solution before him” (p.75). Rovelli dramatizes the story by underlining that “the equation was incorrect every time”, even though by that time Einstein had already calculated the correct perihelion advance for Mercury, using covariant field equations. What I find especially fascinating about this story is how Einstein, who was soon to be socially constructed as a “genius”, made a series of systematic errors and mistakes publicly, and then finally stumbled upon those beautifully simple equations that we now know as the theory of general relativity. It is also disconcerting to think how this happened in the midst of the Great War (Rovelli does not discuss the war but Einstein wrote an anti-war manifesto in response to German scientists’ pro-war “Manifesto of the Ninety-Three”: he could get only three fellow scientists to sign it).
The main claims of Rovelli’s book Reality Is Not What It Seems concern time and space, particularly in the light of recent advances in QT – especially loop quantum gravity that has taken some preliminary steps toward unifying relativity and QT. But first we need a bit of a context. Loop quantum gravity is currently the main alternative to string theory, which has reigned in theoretical physics in spite of being to a large degree a speculative strand of mathematics. Rovelli explains that string theory is not really concerned about space and time but rather tries to write “a unified theory of all known fields, an objective that might be premature given current knowledge” (p.137).
This is a polite way of expressing the trouble with string theory. A rather intolerant community of string theorists have come to dominate many physics departments, where their intolerance seems to be correlated with the haphazard nature of their assumptions and high level of abstraction of their mathematical models.[ii] Critics claim that string theory is not even wrong, because it is really about nothing (or because it can be tautologically used to explain absolutely anything).[iii] String theory may generate some expectations about observable things or effects, but as Rovelli points out at the end of the book, the new particle accelerator at CERN in Geneva has failed to find supersymmetric particles required by typical versions of the string theory. My sympathies lie on the side of those, like Rovelli, who try to solve real-world puzzles rather than to develop excessively speculative mathematical models, attaching an undeserved sense of certainty to them. Rovelli champions the virtues of doubt, open mind and learning as the basis of science.
Rovelli’s ontological claims about time and space may seem disturbing and for some perhaps simply wrong, yet they include genuine insights. But it is also telling that his main claims are represented in an ambiguous manner. Time is not real, but at the end of the book it re-emerges, and so on. Rovelli writes about our limitations as humans:
I think the obscurity of the theory is not the fault of quantum mechanics but, rather, is due to the limited capacity of our imagination. When we try to ‘see’ the quantum world, we are rather like moles used to living underground to whom someone is trying to describe the Himalayas. Or like the men imprisoned at the back of Plato’s cave. (p.120)
Rovelli declares that Kant was definitely mistaken in assuming that Newtonian space and time constitute a priori forms of knowledge, something that we must accept to understand the world. Space is neither a container nor continuous; nor is space divisible ad infinitum. There are atoms of space in quantum fields, though they are a billion billion times smaller than the smallest of atomic nuclei. It is gravitation that constitutes space. The quanta of the gravitational field are quanta of space, the granular constituents of space. Their location is constituted by links and relations to other quanta. What is more, within the boundaries of process there is no definite spacetime or trajectory of quanta. “There is a quantum ‘cloud’ in which all the possible spacetimes and all possible trajectories exist together.” (p.161)
Rovelli is even blunter with regard to time: it does not exist. Even in our everyday world, we never measure or observe time itself. We measure movements or processes in terms of other movements and processes. Things change only in relation to one another; at a fundamental level, there is no time. The flow of time is a useful conception at the macroscopic level of reality, but fundamentally the world is made entirely of quantum fields. At that level time melts into the quantum foam of spacetime. As time disappears from the fundamental equations, it does not exist.
Why it is thanks to quantum mechanics that matter is stable
The mathematics of the basic QT works well – the expectations of QT have been confirmed in numerous experiments – and the models of loop quantum gravity theory may well be confirmed as well. When it comes to understanding what these theories mean, however, we depend on metaphors and philosophy. Rovelli discusses the problem of understanding, but he relies on Plato’s cave metaphor instead of theorising the role of metaphors. We draw on metaphors from our everyday experiences in trying to understand something unfamiliar or strange. This is the origin of the wave/particle duality: two familiar but non-compatible metaphors were needed to account for the evident properties of the quantum world (as revealed already by the early experiments).[iv] But it does not follow that this duality is a good description about what is going on at that level of reality; nor does it mean that particles could really be in two or more states at once.
The simplest and perhaps also clearest version of QT is David Bohm’s realist rewriting of it, providing a theory that accords with our macroscopic world. Known also as de Broglie-Bohm theory (although subsequently developed further by Bohm to address the problems and limitations of earlier versions)[v], it involves determinate sub-quantum-scale processes and a three-dimensional world populated by particles which move according to a non-Newtonian law of motion. This theory holds that the wave-like characteristics of quantum phenomena stem from a real field of quantum potential. The quantum potential depends only on the form, and not in the intensity of the quantum field. The motion of particles produces the overall material structures and processes we happen to recognize in the world we live in.[vi] Although in most ways mathematically equivalent with the standard QT, Bohm’s realist theory, especially in its later versions, is explicit about novel experimental predictions it can yield and which can be tested (although adequate equipment may not yet exist).[vii]
Similarly, the recent and related but different theory of quantum evolution developed by Wojciech Zurek and others revolves around the idea that decoherence is a real process. Through decoherence quantum becomes stable and macroscopic. It is a structured and evolutionary process of selection. Out of the many possible quantum states are selected those that accord with a stable pointer state. Pointer states spread and evolve in a continuous, predictable manner. Successive interactions between pointer states and their environment enable only those states to survive which both produce multiple informational offspring and conform to the predictions of classical physics within the macroscopic world.[viii]
Rovelli himself points out “that thanks to quantum mechanics, matter is stable”. He continues: “Without it, electrons would fall into nuclei, there would be no atoms and we would not exist”. (pp.179-80) These acknowledgements are steps forward, but Rovelli remains ambiguous. His ambiguity seems to stem from an empiricist and (implicitly) reductionist philosophy that underpins his particular interpretation of QT. Rovelli acknowledges his affinity to Bas van Fraassen’s ‘constructive empiricism’, which espouses agnosticism about the reality of unobservable entities.[ix]
On the reality of time
Empiricist philosophy is premised on the idea that only those things that can be directly measured or observed are real. Because time cannot be observed, time is not real. Causation cannot be observed, so it is not real. Only those moments or aspects of quantum processes that can be observed are real. Thus the waves of the wave function are not real either. “What happens between one interaction and the next is not mentioned in the theory. It does not exist.” (p.104) Empiricism in this sense stands in a sharp contrast to scientific or critical realism. For a realist, whatever has causal effects can be real, whether observable or not;[x] and also metaphorical abstractions such as causation and time do make references to reality, although they must be subjected to systematic critique to avoid reification and other fallacies.[xi]
Reductionism in turn means that the basic constituents of the world are assumed to be more real than other levels of reality. Thus ultimately the world would consist of quantum fields. But this seems wrong too. Characteristically the whole of interactions and composition is different from (and more than) the sum of its parts. Over long periods of time, the world is gradually evolving and new structures and forms of complexity arise from the lower level-realities. The emergent wholes can shape their parts. It is precisely the nature of quantum particles and fields that gives rise, due to their interactions, to stable matter as part of curved spacetime.
Time is real but not something that flows on its own (we should not reify our abstractions). Rather time is abstracted from causation, events and processes, many aspects of which are irreversible. In the sense that we live in a unique universe that has a long history of cosmic evolution – itself an irreversible process – it is possible to maintain that there is a preferred cosmic time. Relativity applies to all non-total world-lines, but the overall multitude of different rhythmic processes are happening within a single complex, dynamic and relational process.[xii] A physicist may imagine (human-built) clocks in every sector of the cosmos and argue that although time runs everywhere at different speeds, the universe is roughly the same everywhere and thus the time-differences are small. From the point of view of causal-historical processes, however, what matters is the process of cosmic evolution involving emergence and new forms of complexity. This is the true meaning of the claim that the universe as a whole (of which may see only a minuscule part) is 14 billion years old.
The present “now” is not a point on an abstract segment of a line, but an indefinite boundary state of a process that is happening in spacetime. A number of processes may not only occur simultaneously – subject to Einstein’s relativity – but coalesce and interact in various ways. The duration of the present depends on the event or context which is happening. Once the universe gets started and stable matter exists, new processes evolve and produce more complex forms of matter and other structures, ultimately making also biological and cultural evolution possible. All the emergent layers are real and causally efficacious, and can shape lower levels at least within the confines of the physical and chemical laws[xiii] (moreover, arguably also physical structures are malleable, however stable they may have been so far)[xiv].
The enmeshment of ontology with ethics and politics
Interpretations of QT are thus largely dependent on the metaphors we use and on our philosophical commitments. What is interesting for a social scientist is that empiricism, atomism and reductionism – the key ingredients of the modern scientific metaphysics – evolved in tandem with the historical development of capitalist market economy. From a social scientific point of view, what empiricism means is that the social world must consist only of individuals that can be directly perceived, rather than of social structures or wholes that cannot be perceived in the same way.[xv]
It can be argued that empiricism and individualism are multiply connected, which in turn makes the historical association between empiricism and liberalism understandable. There are close links between atomist social ontology and, say, the justification of private property and the related ‘fundamental’ rules of justice. A key logical connection stems from an isomorphism between philosophical atomism and liberal individualism. Although it is evident that human individuals consist of complex structures organized through multiple complex principles, a structure-preserving mapping from atomism to liberal individualism is possible. The essence of private property is separateness and exclusiveness. In liberal political theory, whenever scarcity prevails, the right to exclude others from the use or benefit of something has usually been presented as absolute, permanent and therefore inalienable, but freely alienable by consent, i.e. by contract. This line of reasoning leads to the classical liberal three principles of justice articulated for instance by David Hume: stable possession, transference of property by consent, and the obligation to fulfil promises. Hume also stressed the importance of respecting human life as a precondition for all these three (no wonder then that the first 19th century peace movements were liberal and characteristically associated with free trade-ism).
Ontology is therefore enmeshed with all kinds of ethical and political considerations. In Rovelli’s case there seems to be an ambivalence between seeing the world in relational, holistic and processual terms, involving real emergence and complexity, and sticking to the metaphysics of empiricism, atomism and reductionism. My question is whether his ambiguously stated denial of the reality of space, causation and time is in fact just a consequence of the unwillingness to take sufficient distance from the Western metaphysical tradition grounding the politics of economic liberalism?
Of course, this question is even more acute in the case of radically speculative versions of QT, such as the many-worlds interpretation, which Rovelli does not espouse.
For part II, click here
Endnotes
[i] For a series of most useful comments, I am thankful to Haider Khan (a fellow political economist and one-time student of David Bohm), Sofia Patomäki (a post-graduate particle physicist and a half-sister of mine) and Syksy Räsänen (a cosmologist who just published a book on the Israel-Palestine conflict, demanding boycotts against Israel). It goes without saying that I am alone responsible both for the remaining errors and for the ontological, epistemological and axiological views that I express and develop in this essay.
[ii] In his examination of the string theory’s and its status in physics, Lee Smolin stresses that the string theory evolved rapidly into a well-resourced but cliquish community. Interestingly for a social scientist, there is a close parallel to neoclassical economics. Many researchers in both fields are undoubtedly talented, hard-working and committed. Yet not a single general textbook statement derived from neoclassical research has obtained solid support from replicable empirical or historical studies. The literature is vast, see e.g. Hill, Rod & Myatt, Tony (2010) The Economics Anti-Textbook. London: Zed Books. In a parallel manner, most of string theory’s claims cannot be tested even in principle; and those aspects that may have at least some empirical implications, have so far failed in experiments. Smolin, Lee (2008) The Trouble with Physics. London: Penguin Books.
[iii] Woit, Peter (2007) Not Even Wrong. The Failure of String Theory and the Continuing Challenge to Unify the Laws of Physics. London: Vintage Books.
[iv] Abstract concepts are largely metaphorical and truth is mediated by our embodied understanding and imagination. Complex metaphors are built out of primary metaphors plus forms of commonplace knowledge (folk theories, widely accepted knowledge and beliefs, including scientific theories). Thus when QT emerged, ‘waves’ and ‘particles’ were not only widely accepted metaphors in physics but also based on commonplace knowledge. George Lakoff and Mark Johnson suspect that our fundamental theories of physics will remain partial and dependent on the human sphere of experience. “[I]t may be the case that the limitations of human conceptual systems will make it impossible for there to be fully general, global scientific theories. For example, general relativity and quantum mechanics are incompatible theories, each with an enormous range of converging evidence. String theorists seek a unified theory of physics, but we do not yet know and we may never know whether that is possible. All that may be possible are partial theories, theories that are what we will call ‘locally optimal’-incompatible, but widely comprehensive (though not fully comprehensive) theories supported by considerable converging evidence. Perhaps locally optimal theories are the best we can do using human minds. We don’t know. Quantum mechanics and general relativity may be locally optimal, globally incommensurable theories.” Lakoff, George & Johnson, Mark (1999) Philosophy in the Flesh. The Embodied Mind and Its Challenge to Western Thought. New York: Basic Books, p.92.
[v] See Bohm, David (2002) Wholeness and the Implicate Order. London & New York: Routledge (Classics), pp.97-140 [originally published in 1980].
[vi] Kiessling, Michael K.-H. (2010) “Misleading Signposts along the de Broglie-Bohm Road to Quantum Mechanics”, Foundations of Physics, 40 (4): 418-29. In Bohm’s theory there is no wave-particle duality or collapse of the wave function. In their stead, active information and non-locality feature centrally (it is worth noting that Rovalli too discusses positively the role of information at the end of his book). The Undivided Universe was Bohm’s final statement, with B.J.Hiley, of his theory. Bohm, David & Hiley, Basil J. (2005) The Undivided Universe. An Ontological Interpretation of Quantum Theory. Milton Park & New York: Routledge, originally published in 1993.
[vii] Perfect knowledge about the sub-quantum level may be impossible. Bohm explains that “[….] one aims only by a few crucial experiments to show that the sub-quantum level is there, to investigate its laws, and to use these laws to explain and predict the properties of higher-level systems in more detail, and with greater precision, than the current quantum theory does.” Bohm, Wholeness and the Implicate Order, p.135.
[viii] For a recent popular summary of this theory, see Ball, Philip (2017) “Quantum Common Sense”, Aeon, 21 June, available at https://aeon.co/essays/the-quantum-view-of-reality-might-not-be-so-weird-after-all. For an original scholarly statement, see Zurek, Wojciech H. (2009) “Quantum Darwinism”, Nature Physics 5 (3): 181-8.
[ix] Rovelli mentions also Michael Bitbol and Mauro Dorato on p.120, complicating the picture. For example, Bitbol argues for a (neo-)Kantian interpretation of QT (which may be in some tension with Rovelli’s Kant-critique). Bitbol assumes epistemological emergence especially with regard to mind but also more generally, yet denies ontological emergence; Bitbol, Michel (2007) “Ontology, matter and emergence”, Phenomenology and the Cognitive Science, 6 (3): 293-307. Van Fraassen is, to the best of my knowledge, the best known philosopher of the three, and his ‘constructive empiricism’ seems to accord with Rovelli’s programmatically anti-metaphysical QT. According to Van Fraassen, science can make no stronger commitments than that a theory is empirically adequate if it fits what is observed; one cannot make any commitments to the truth of the unobservables. Van Fraassen’s paper on Rovelli’s interpretation of QT hinges upon arguments based on observable-dependency, and thus rely on empiricism that tends to be ontologically reductionist, although it may deny many forms of reductionism epistemologically, pragmatically or otherwise. See van Fraassen, Bas (1980) The Scientific Image. Oxford: Clarendon; and van Fraassen, Bas (2010) “Rovelli’s World”, Foundations of Physics, 40 (4): 390–417. For a critical discussion on van Fraassen, focusing on his key notion of contrast explanation, see Morgan, Jamie and Patomäki, Heikki (forthcoming) “Contrast explanation in economics: its context, meaning, and potential”, Cambridge Journal of Economics, doi:10.1093/cje/bex033.
[x] To be is not to be perceived, but rather (in the last instance) just to be able to do. The causal criterion of reality, which has been known in philosophy since Plato (“the Eleatic principle”), is also the basis of claims about the reality of emergence. Roy Bhaskar makes a sharp distinction between the perceptual and causal criterion of existence: “A magnetic or gravitational field satisfies [the causal] criterion, but not a criterion of perceivability”. Bhaskar, Roy (2011) Reclaiming Reality. A Critical Introduction to Contemporary Philosophy. London & New York: Routledge, p.194 [originally published in 1991]. However, unobservables can and often do become observable (for instance, a magnetic field can easily be seen with the aid of iron powder and piece of paper, and many social relations can be observed by means of reading), see Patomäki, Heikki (2014) “On the reality of causes: a response to Ned Lebow”, Newsletter of Qualitative and Multi-Method Research, American Political Science Association, 12 (2): 11–15; available at https://www.maxwell.syr.edu/uploadedFiles/moynihan/cqrm/ Newsletter%2012_2.pdf.
[xi] For instance, the classical Newtonian conceptions of time and space stem from a fallacy of misplaced concreteness, whereby particular metaphors – ‘time moves’ and ‘space is an empty container’ – are turned into concrete things in human imagination. About the metaphorical construction of time, space and causation, see Lakoff & Johnson, Philosophy, op.cit., pp.30-6, 137-94. The fallacy of misplaced concreteness was first mentioned and discussed by Whitehead, Alfred N. (1997) Science and the Modern World. New York: Free Press (Simon & Schuster).
[xii] This argument arises from the observation that the standard interpretation combining Einstein’s special relativity with the Friedmann-Robertson-Walker-Lemaître solutions of the field equations of the general relativity fails to exclude preferred cosmic time. Unger, Roberto M. & Smolin, Lee (2015) The Singular Universe and the Reality of Time. Cambridge: Cambridge University Press, p.188, pp.321 et.passim.
[xiii] Thus, to use a few well-known examples, water has different properties than hydrogen or oxygen and those properties are causally efficacious; life moves and produces matter in a way that mere physical and chemical processes would not do; technologically advanced and meaningful human practices not only destroy but also change life forms and their environments; and so on. There is of course no reason to deny the role of non-causal explanations and non-explanatory arguments in science. The causal criterion says only that whatever has causal effects, exists and is real.
[xiv] Laws of physics do appear very stable in the contemporary cooled-down universe, but they may not be immutable. When the relational structures change, so do laws. See Unger & Smolin, Singular, op.cit., pp.259-301, 485-6.
[xv] As Bhaskar, Reclaiming, op.cit., p.81, reminds us, a social structure is “a most peculiar kind of entity: a structure irreducible to, but present only, in its effects”. For a detailed discussion of the concept of social structure, see Patomäki, Heikki (1991) ”Concepts of ’Action’, ’Structure’ and ’Power’ in ’Critical Social Realism’: A Positive and Reconstructive Critique”. Journal for the Theory of Social Behaviour, 21 (2): 221-50.