Abstract
In this paper, I discuss the possible relations between Fritz London’s account of the status of the observer in quantum physics and transcendental phenomenology. Firstly, I discuss Steven French’s interpretation of London’s thesis as a phenomenological account of the status of the observer, along with the objections Otávio Bueno has brought forward. Secondly, refusing in part both French’s and Bueno’s theses for several reasons, I propose another way of reading London’s thesis in the framework of transcendental phenomenology. Namely, I put London’s account of the observer against the backdrop of Husserl’s analyses of the objectifying acts and objectual constitution. Finally, I end this article with some criticisms of what seems to me the ontological indigency of the Copenhagen interpretation of quantum physics, to whose “spirit” London also belongs.
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Notes
I suppose that by “orthodox solution” French is referring himself to von Neumann’s construal of the measuring apparatus as entering in a superposition with the quantum system. Bohr had doubts about this approach. The issue is normally presented as a distinction between the micro and macro realms, to which Bohr, contrary to von Neumann, was adamant. However, Bohr’s real insistence was about the necessity of using the concepts of classical physics in order to extract information from the physical experiences. While quantum entities and apparatuses are entangled, for getting information one must establish a “cut” between them, so that one proceeds as if the apparatus and the measured entity were not entangled. The question is not that the measuring apparatus is a macro physical entity, but rather that one is obliged to rely on the “classical” physical distinction between measured system and measuring apparatus (see Howard 2004, 674–675). As Bohr also belongs to the quantum “orthodoxy,” later (in the 1950’) named the “Copenhagen interpretation,” one must recognize that there were at least two tendencies and not a uniform, monolithic trend. Namely, von Neumann’s approach, and the complementarity-approach by Bohr, which never spoke of a “collapse” of the wave function and always insisted in physicalizing the observer, taking it as a physical apparatus submitted to a “classical-like” separation from the measured phenomena. As far as I can see, given his later works on the covalent bond from a quantum perspective, London is more in keeping with von Neumann’s construal.
French (2002, 468).
See London (1923); for details, see Gravoglu (1995, 11–14). Gathering information from Husserl's correspondence, several facts can be established. First, London’s essay was pointed to Moritz Geiger for revision. However, he declined because it was an urgent task and he was not available at the moment, so that the revision was assumed by Pfänder himself (“Londons Arbeit hat Pfänder übernommen, da die Sache drängte, und ich gerade damals verschiedene Doktorarbeiten zu korrigieren hatte und gleichzeitig einige Gutachten für die Fakultät anzufertigen waren”; Husserl 1994-II, 109). Second, Geiger also informed Husserl in the same letter that, given the new strictures for the doctoral exams at the University, only Fritz London obtained a summa cum laude in Philosophy (“Wir haben seit zwei Semestern eine sehr erschwerte Promotionsordnung, nach der summa cum laude wirklich ein ganz besonders seltenes Prädikat ist. So hat z.B. seit Bestehen dieser Verschärfung in Philosophie nur London summa cum laude promoviert, und in Kunstgeschichte ist Dr. Rosenberg der erste”; Husserl 1994-II, 110). Third, Pfänder later told Husserl that London’s work was initiated with him and, while he did not agree with everything, it was sent to the publisher of the Jahrbuch (“Vom Jahrbuchband VI höre ich gar nichts mehr. Die Arbeit von Dr. London habe ich selbst durchgesehen, da Herr Kollege Geiger damals gerade keine Zeit dazu hatte. Die Arbeit hatte Dr. London bei mir angefangen; ich bin nicht mit allem einverstanden, habe sie aber doch damals gleich an den Verlag geschickt. Sie ist wohl inzwischen längst gedruckt”: Husserl 1994-II, 173). Finally, Husserl informed Ingarden that a new issue of the Jahrbuch wil soon appear with valuable contributions, namely two “mathematical-philosophical”; clearly, he was referring himself to the essay “Beiträge zur phänomenologischen Begründung der Geometrie und ihrer physikalischen Anwendungen,” by Oskar Becker, which studied under Husserl and Hermann Weyl, and to Fritz London’s own work (“Jahrbuch VI ist fertig und erscheint in diesen Tagen, mit wertvollen Beiträgen, besonders auch 2 philosophisch-mathematischen”; Husserl 1994-III, 217). As far as I know, there are no other references to Fritz London in Husserl’s correspondence. London’s passage through Husserl's inner phenomenological circle was brief and seems to have left no marks on the latter. The other way around, London’s acquaintance with phenomenology was to a great extent a result of his contacts with Aron Gurwitsch in Paris in the thirties. At that time, Gurwitsch was deeply interested in Gestalt psychology, phenomenology of science and, important enough, in the phenomenological theory of constitution, preparing an essay that was a result of his lectures at the Sorbonne titled La phénoménologie constitutive: Une esquisse. Later, I will develop the bond between theory of natural science and phenomenology of constitution in London’s essay on the measurement problem.
French (2002, 470).
London and Bauer (1983, 218–219).
French recognizes this; see French (2002, 469–470).
Bueno (2019, 130).
Bueno (2019, 138).
Bueno (2019, 136).
See, for instance, Wigner (1995, 257).
Bitbol (2000, 47) drew attention to the curious case of Darwin’s work in wave mechanics. Darwin’s fundamental issue regards the corpuscle-wave dualism that plagued quantum mechanics since its very beginning. The article tries to put together a wave-like physical, objective description of the quantum systems and a particle-like interpretation when they came to be observed. Rejecting the prevailing “philosophy of modern physics that our theories should only contain observable quantities,” i.e., a kind of scientific positivism professed by Heisenberg and so many others, his proposal amounts to consider, at an ontological basis, “the wave function ψ as the central feature of the quantum theory” (Darwin 1929, 391). The main idea is that the wave description is enough, and that the physicist can postpone indefinitely the account of the physical behavior of the system by the language of particles and trajectories, needing to introduce it only when, and if, a measurement is finally made. The measurement entails a gain of information concerning the system, and the particle-like representation is an interpretation introduced by the conscious observer. As he expresses himself in the final part of his essay, which is worth quoting at length, “[…] there is no need to invoke particle-like properties in the unobserved parts of any occurrence, since the wave function ψ will give all the necessary effects. […] The observed result is given by interpreting the effect of the original system […] If we are considering the scintillations of α-particles, we usually think of the stopping of the α-particle as the observation. The scintillation is due to the bursting of a small zinc sulphide crystal, and we might include the atoms of the crystal in our ψ along with the α-wave. We might go further by including the emitted radiation and take as the observation the intensity of light in the retina eye. Even this is not all, for we might include the photoelectrons emitted from the retina, and the optic nerve also, but somewhere in the brain we are absolutely compelled to stop. We can say that all occurrences right up the brain are non-committal, in that they contain no definite implication where and when the α-particle came; it is only after our consciousness has animated the proceedings that it is possible to infer back and describe what happened in the familiar language of particles. If these ideas are admissible, we can put the inexplicable feature of the quantum theory, the irreconcilability of wave and particle, in exactly the place where we have got in any case to have an inexplicability, in the transfer from objective to subjective.” (Darwin 1929, 392–393, my emphases).
See Wigner (1995).
Wigner apud Bueno (2019, 132).
London and Bauer (1983, 258, 1939, 186). I have slightly altered the English translation, namely, translating regard by look, instead of scrutiny, and altering the content of the text put into parentheses. Indeed, the English text says the opposite of the original: where London and Bauer write “mais, bien entendu, après leur couplage,” the English translation reads, “but of course after the coupling is turned off”—the question is not whether one knows the state of the object after turning off its coupling with the apparatus, but that one knows the state of the object and of the measuring apparatus after their coupling.
As I stressed, the English translation erases systematically this phenomenological key concept, rendering it by “creation,” which is a term that Husserl expressly avoids because it is incapable of expressing from the transcendental point of view the dependence-relation of the objectual correlate. For instance, „Ich bin es, der diese für mich seiende Welt und mich selbst als Menschen mit dem ganzen Geltungssinn geschaffen hat, oder, wenn man das arge Wort „schaffen“ vermeiden will, in mir hat es diesen ganzen Sinn und sein „Es ist und ist so und so“ gewonnen durch meine Bewusstseinstätigkeiten, durch meine Vermögen, durch meine verborgenen assoziativen Sinnbildungen. […] Ich und Andere als die Welt konstituierende Subjektivität […] heißen „transzendentale“ und danach die konstituierenden Leistungen selbst transzendentale.“ Husserl (2002, 286 and 289).
“Or l’équation de Schrödinger présente tous les caractères d’une connexion causale: si la fonction ψ est connue à un moment donné, elle est déterminée pour tout instant ultérieur. Il semble donc difficile de concevoir que cette fonction contienne néanmoins une collection de statistiques.” London and Bauer (1939, 164, 1983, 232).
“Ainsi l’élément statistique n’interviendrait qu’à l’occasion d’une mesure et si la fonction ψ nous fournit des probabilités, elle ne le fait qu’en vue d’une mesure éventuelle. Ce ne sont donc pour ainsi dire que des probabilités ‘potentielles’ qui entrent seulement en vigueur à l’occasion d’une mesure actuelle.” London and Bauer (1939, 165, 1983, 233).
“En mécanique quantique un objet est porteur, non pas d’un ensemble défini de propriétés mesurables, mais seulement d’un ensemble de statistiques ‘potentielles’ se rapportant à ces propriétés mesurables, statistiques qui entrent seulement en vigueur à l’occasion d’une mesure effective bien définie. Si l’on fait abstraction de toute mesure, il est dénué de sens de se représenter ces propriétés mesurables comme réalisées; la forme mathématique même de ces statistiques ne le permet pas.” London and Bauer (1939, 186, 1983, 259).
In the incisive expression of Darwin, “We are led to the conception of a sub-world, which contains no mention of observation at all. In this sub-world ψ is an unthinkably complicated function of all the variables associated with all the particles of the world; nothing definite is happening at all, but it expresses simultaneously everything that could possibly happen.” Darwin (1929, 393). Max Jammer also accentuates this enigmatic aspect: “As long as the motion [of a quantum mechanical system] is described by the deterministic Schrödinger time-dependent equation, no events could be considered to take place in the system. […] In other words, if the whole physical universe were composed only of microphysical entities, as it should according to the atomic theory, it would be a universe of evolving potentialities (time-dependent ψ functions) but not of real events.” Jammer (1974, 474).
London’s phrase is a little misleading when he says that the interaction with the apparatus does not by itself conduce to a new pure state. This statement is in plain contradiction with the doctrine of section 13 concerning the Stern-Gerlach experiment, where he expressly writes that “ces deux atomes, qui ont passé la fente ont la propriété désirée et nous pouvons leur attribuer la fonction d’onde du cas pur en question.” London and Bauer (1939, 185, 1983, 257). The statement must be read cum grano salis, so to speak. What it means is that the formalism gives a statistical probability that calculates the possible outcomes of the interaction, but that is, by itself, incapable of deciding which is the value that obtains.
London and Bauer (1983, 252). This paragraph is an addition to the English text based on a handwritten note inserted by London in his own copy, as the translator explains. I have write “constitutive action” instead of “creative action” based on the fact that the translator, in other passages, writes “creation” where London’s writes “constitution,” and because “constitution,” used by London, certainly echoes the phenomenological, Husserlian concepts of Konstitution and konstituieren. I have also some doubts about the expression “making objective.” Perhaps, London is simply writing in German “zum Gegenstand machen,” or “Objektivierung,” or even “rendre objectif,” “objectivation,” if he was writing in French, terms which belong altogether to the phenomenological jargon.
French (2002, 484). French seems to me entirely right when he states that, “This separation [he refers to the “birth” of the observer by an act of reflection] should not be thought of in terms of consciousness ‘causing,’ in whatever sense, the wave function to collapse.” Contrary to this interpretation, Max Jammer states that “London found in quantum mechanics a field where he could meaningfully apply Lipps’ and Becher’s philosophy,” namely “Theodor Lipps’ psychological theory of empathy” and Becher’s “interactionism,” that is, the doctrine that “physical processes […] pervade the brain in a continuous course and produce, in addition to physical effects, psychic effects which in turn decisively affect physical events” (Jammer 1974, 482, 484). Despite Jammer’s solid interpretations of the development of quantum physics, I cannot find any trace of Becher’s theses in London’s essay, even less any productive application of Lipps’ (and Husserl’s) theory of Einfühlung.
French (2002, 485).
More recently (French 2020) stressed the supposed phenomenological framework of London’s reference to immanent knowledge in the act of observation. I disagree with his argument. Firstly, the text by Husserl he quotes, putting “pure immanence” as a principle of authentic knowledge (Ideas-I, section 59; Husserl 1983, 136) refers to the exclusion of material-eidetic disciplines by the epoché, and not to reflection. There, “pure immanence” means reflective description of the noetic-noematic structures, i.e. both the really (reel) and the intentionally immanent, and not to the consciousness of an “I.” Husserl himself noted in a handwritten note that the expression “pure immanence” could misleadingly “look as though only real data were to be taken into account.” Secondly, transcendental reflection entails: The epoché or exclusion of any transcendency; the discovery of the new realm of being of transcendental subjectivity, given to itself in transcendental experience; the isolation of an immutable point of identity, the “I,” which is empty and given as a transcendence in immanence. Clearly, this is not what is at stake when the physicist performs an act of observation. The “immanent knowledge” that is at stake is the psychological capability for self-awareness, to which there is, to be sure, a phenomenological description at a transcendental level. But describing phenomenologically an act of self-awareness and being aware, as a physical observer, of its own sates are very different things.
As far as I can see, French ingenious insight is that the “I” will spring from the quantum superposition, so that, by means of self-awareness of its own internal states, the "I" will be capable of bring the superposition to a definite state. However, I believe that this hermeneutic strategy does not work. One faces a dilemma: Either the “birth” of the “I” is the cause of the collapse of the wave function, and in this case London is committed to a mentalistic account that is open to Putnam’s criticisms, or the “I” does not collapse the wave function, and, in such a case, the superposition will remain, at the sub-"I" quantum level, while at the "I"-level there will be a definite subjective state that has no correspondence with the quantum objective state. It is worthless to “dematerialize” the “I” by means of a transcendental account. If it emerges from the superposition, one will have a naturalistic account for the genesis of the “I” and not a transcendental one, because, for the latter, the subjectivity is the prius, which cannot be derived from a non-subjective realm. “Consciousness arrives out of consciousness,” as Husserl once remarked, even from the depths of the unconscious. However, this phenomenological “unconscious,” if there is one, is itself for consciousness, as a process of self-constitution that cannot be equated with a naturalistic account concerning the way a conscious subject arrives from an “objective,” physical quantum superposition. For a Husserlian inspired phenomenology, the question is not how there is a subject for an objective world, but rather how there is an objective world for a subject. It is not a matter of deriving subjectivity by spontaneous acts of reflection from an objective world as described by quantum physics. For Husserl, this would be Naturalism and Objectivism, thus, the “forgetting” of subjectivity. The “sitting point” of Husserl’s subjectivity is not the quantum realm but the lifeworld. The quantum realm is rather a substruction performed on the subjective-relative structure of the lifeworld. For a phenomenological theory of physical science, the issue is the description of the sense institutions that constitute the world of physics as a true world “behind” the lifeworld.
London and Bauer (1939, 187, 1983, 259). I translated this quote directly from the French text because the English translation does not follow the original in some important details. Namely, it puts a question mark at the end of the sentence, turning a statement into a question followed by a “No,” which does not appear in the French version. It seems that the English translation follows a modified text (by London himself?) I could not find.
As Robinet writes, “L’adhésion de Malebranche et du groupe des mathématiciens qui l’entouraient aux mathématiques de l’infini constitue l’un des plus spectaculaires revirements de l’histoire de la philosophie e du mouvement des idées” (Robinet 1961, 205). Leibniz fundamental role in overcoming Cartesian mathematics of finite magnitudes and in Malebranche’s conversion to the analysis of the infinite is well known. More than the algebraization of geometry, it was the “calculus of the infinite” that acted as a leading force that placed mathematics in its modern setup and prepare physics to deal with non-intuitive magnitudes (such as “evanescent quantities,” i.e., limits, or instantaneous rates of change of velocity, i.e., accelerations), accessible not through perception but only through the mathematical formalism.
See Bolzano’s posthumous work Paradoxien des Unendlichen. Leipzig: Reclam, 1851.
Actually, the doctrine of objectifying acts was developed in Logical Investigations before the discovery of the epoché. After Ideas-I, the term almost overlaps with the concept of a noematic sense that contains the intentional object, or the object as intended, together with a thetic character. However, the account of objectifying acts given in the Logical Investigations can be reinstated in the context of the phenomenological epoché.
Actually, Husserl introduces the epoché firstly as a universal methodical procedure whose target is the general thesis of the natural attitude: the Weltdoxa as such (Husserl 1983, 60–62). Only after introducing this universal suspension does Husserl endeavors to specify the system of reductions or particular epoches. See Husserl (1983, 131–145).
Husserl (2002, 289).
In section 90 of Ideas-I, Husserl stresses the difference between noematic statements and statements about actuality. His famous words are worth considering: “It is clear that all these descriptive statements, even though they may sound like statements about actuality, have undergone a radical modification of sense […]. “In” the reduced perception […], we find, as indefeasibly belonging to its essence, the perceived as perceived, to be expressed as “material thing,” “plant,” “tree,” “blossoming,” and so forth. […] The tree simpliciter, the physical thing belonging to Nature, is nothing less than this perceive tree as perceived which, as perceptual sense, inseparably belongs to the perception. The tree simpliciter can burn, be resolved into the chemical elements, etc. But the sense—the sense of this perception, something belonging necessarily to its essence—cannot burn up; it has no chemical elements, no forces, no real properties” (Husserl 1983, 216).
Husserl (2001, 119–122).
London and Bauer (1983, 252).
See especially the last two chapters of Ideas-I, where Husserl expressly addresses the issues of evidence, as the last but not only foundation for rational belief and positing, and the set of formal and material ontologies that form an all-encompassing phenomenology of reason (Husserl 1983, 327–370).
Actually, the theory of the horizon is only fully developed in the twenties. However, there are seeds of it in Ideas-I. See Geniusas (2012).
Bell (2004, 52).
Bell (2004, 53).
Husserl (1983, 313).
It may seem awkward to identify the object simpliciter with a fulfilling act that, in addition, is presented as determining the intending sense. Certainly, the object simpliciter is not necessarily the target of an intuitive act. It is just an identification pole that is constituted in a synthesis of identity among several different objects in the how. However, here, the object simpliciter must be accounted for as an act of perception. This is only a possible case, but it is the case that fits the situation. Regarding the determining and not only fulfilling function of the intuitive act, it is quite trivial in certain forms of partially undetermined intending sense. Suppose that I leave home thinking of “the first cat I will see.” I do not know if it will be a white cat, a brown cat, a black cat or else. When eventually I perceive a cat during my walk that actually is black, the perceptual sense does not only fulfill the intending sense, but also determines it.
Apparently, my account of the perception of gk does not fulfill the phenomenological conditions for being accounted for as the object simpliciter. As Husserl puts it, the object simpliciter is defined as an identity pole that can be intended with a multiplicity of different noematic senses. However, at a closer look, the perception of gk fulfills this condition. Indeed, gk, say the perception of the position of a pointer or of a set of dots on a plate, can be the content of perceptual acts with pretty different senses. For realizing this, one must only considerer what senses the layman would attribute to such perceptual objects.
Aerts (1999, 148).
Dirac has pointed out this situation, presenting it as mathematical approach that can be compared to Fourier’s analysis, which decomposes a continuous function in an infinite sum of sine and cosine waves: “The general principle of superposition […] requires us to assume that between these states there exist peculiar relationships such that whenever the system is definitely in one state we can consider it as being partly in each of two or more other states. The original state must be regarded as the result of a kind of superposition of the two or more new states, in a way that cannot be conceived on classical ideas. […] The procedure of expressing a state as the result of superposition of a number of other states is a mathematical procedure that is always permissible, independent of any reference to physical conditions, like the procedure of resolving a wave into Fourier components” (Dirac 1948, 12; my emphasis).
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Alves, P.M.S. Fritz London and the measurement problem: a phenomenological approach. Cont Philos Rev 54, 453–481 (2021). https://doi.org/10.1007/s11007-020-09521-w
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DOI: https://doi.org/10.1007/s11007-020-09521-w