13 декабря 2017 г.

Astrophysics-Philosophy — MSU-Helsinki

Philosopher of astrophysics Anastasiia Lazutkina on the philosophical traditions of Moscow and Helsinki and the contemporary philosophy of physics

Graduated from Lomonosov Moscow State University, Faculty of Philosophy, exchange with a grant at the Department of Theoretical Philosophy of the University of Helsinki. Currently studies theoretical physics at Leipzig University, Germany.

Русская версия

Date Palm Compote: What is the difference between philosophical education in Moscow and in Helsinki? What is the difference and similarities between our philosophical communities?
Anastasiia Lazutkina: At the University of Helsinki, as in the Moscow State University, there has always been a strong logical school. Three semesters of studying logic at the Faculty of Philosophy of Moscow State University give a student a good background for the application of the logical apparatus in the analysis of other problem areas. In Helsinki, in addition to having a large number of specialized courses in logic, the logical apparatus itself is widely used in other courses that are not directly related to logic.

However, the main difference is that the philosophical education in Moscow State University focuses on the study of the history of philosophy, while in Helsinki the main emphasis is on the problems of philosophy, not its history. In this way, the curriculum is differently constructed. In addition, primary sources are utilized somewhat different. In MSU, the student must read the works of, for example, Aristotle, Kant, Heidegger, etc. While in Helsinki the history of philosophy is not the main part of the curriculum, as already mentioned, the emphasis is on the problems of philosophy. During my training in the philosophical department in Helsinki, I came across a situation that surprised me when students cannot say anything about Hegel, except that he is a German idealist, and Thomas Aquinas, in addition to being a commentator of Aristotle. At the same time they are surprised by the fact that at MSU more attention is paid just to Thomas Aquinas and Hegel, and not to Hilary Putnam, David Lewis, Saul Kripke, John Rawls, etc. This situation is explained by the fact that teaching at the philosophical department in Helsinki begins with the texts of modern analytic philosophers. And the basis for all discussions will be the ideas of Russell, Frege and Moore. Moreover, the knowledge of their ideas is necessary for admission. Here are some of the topics on which you need to write an essay on the entrance exam: “Boolean algebra”, “The Russell’s Paradox and his theory of descriptions”, “Wittgenstein’s philosophy of mathematics”, “Moore’s ethical intuitionism”, “Ethical anti-realism: logical positivism, emotivism”, “Frege’s philosophy of language”.
Also, an important difference of the University of Helsinki from the Moscow State University is a non-fixed training program, in which the student himself chooses a list of courses that he plans to pass, but he has the opportunity to change his choice at any time. In addition to the main specialization (for example, philosophy, economics, chemistry), the student must choose a complementary specialization, according to which he will take the exam as well. Philosophy students often choose biology, mathematics, or physics as such specializations. As a result, a synthesis of sciences and philosophy takes place.

DPC: How is the concept "philosophy of science" understood at Moscow State University and in Helsinki?
A.L.: This question is a continuation of the previous one. Due to the fact that students acquire additional specialization, it allows them to carry out a philosophical analysis within the chosen additional discipline. Thus, this additional specialization in any of the sciences, allows the philosopher to keep abreast of modern scientific discourse.
Therefore, in my opinion, at the University of Helsinki, more emphasis is placed on the philosophy of specific sciences in their current state, while at Moscow State University — on the philosophy of science in general (general philosophy of science), the history of science and the history of the philosophy of science.

DPC: What is the role of logical positivism in contemporary philosophy of physics?
A.L.: The best part about logical positivism is the strict logical and methodological methods for the analysis of science. Thanks to the logical positivists, the philosopher of science in our days has the opportunity to be heard by scientists. Due to my personal experience in participating in international conferences on astrophysics I can say that it is much more productive to work with scientists using the language of formulas. Therefore, it is justified to assert that logic serves as a link between philosophy and science.
Many contemporary philosophers of physics are ready to engage in the kind of metaphysical speculation that the logical positivists would have considered meaningless. As an example, one might mention the debate between substantivalists and relationalists regarding the nature of space, which is quite active nowadays. However, there are philosophers of physics (and philosophers of science, more generally) who attempt to carry on the spirit of logical positivism and logical empiricism in their work. An influential example would be the collaboration of James Ladyman and Don Ross, who are proponents of a verification principle. They argue that unverifiable statements are unknowable, although not meaningless, and this has generated plenty of discussion regarding the status of analytic metaphysics. Although my approach to philosophy of physics is also partially inspired by the work of Carnap (etc...), I am perhaps more permissive with regard to my attitude toward other kinds of philosophical projects. As long as a philosopher does not try to equate the kind of epistemic progress achievable in metaphysics and science, I do not see why he could not engage in a philosophical project that disregards the verification principle.

DPC: What, in your opinion, is now the mainstream of the philosophy of physics? Who is a living classic? What problems attract the most attention?
A.L.: There are no living classics! But, nevertheless, several key figures can be identified: M. Lange, J. Ladyman, D. Albert. These scientists work in the still mainstream areas of the philosophy of physics: the philosophy of quantum mechanics, the philosophy of space and time. Unfortunately, the philosophy of astrophysics is not as popular as I would like. However, astrophysicists are increasingly trying to be philosophers in connection with the growing need for philosophical analysis. Such an imitation of the philosophy may be one of the reasons why now there are so many "bad" books on the philosophy of astrophysics.

DPC: In your work you use the ideas of Soviet logician E.K. Voishvillo. What is the relevance of his work to contemporary philosophy of physics?
A.L.: Voishvillo is widely known for his work on logic, but in addition he offered a methodological scheme for the analysis of science. For example, he developed a classification of theoretical objects and theoretical terms of scientific theory, which is applicable to modern science and makes possible its methodological analysis. The classification is based on the method of introducing objects into a theory. These theoretical objects can be divided into several classes, one of which is the class of hypothetical objects. Hypothetical objects are objects that are introduced into theory when constructing an explanation of certain phenomena. When such objects are postulated, they are not observed, but with the development of science they can be discovered, and thus acquire the status of real objects, or, being fictitious, are deleted from theories. The history of science knows a lot of such objects: phlogiston, elementary neutrino particle, Higgs boson, etc. Voishvillo’s classification is well applicable to modern scientific theories, so in my research I analyze the standard cosmological model ΛCDM (Lambda-Cold Dark Matter), according to which two theoretical objects: dark matter and dark energy (the existence of which was not independently confirmed by any experiment) constitute 95.1% of the mass-energy of the universe. These objects, according to Voishvillo, are hypothetical. But physicists do not distinguish between two types of existence: the existence in the universe of theory and the existence in the universe of real physical objects. This leads to an incorrect interpretation of the status of such hypothetical objects as dark matter and dark energy. Thus, the logical and methodological scheme of E.K. Voishvillo explains the structure of scientific theories and helps to reveal the status of the objects of the theory. In addition, this scheme provides a good basis for possible extensions and adaptations. Based on the classification of Voishvillo, in my work I propose a refined classification of hypothetical objects to modern astrophysics.
The introduction of hypothetical objects is not the only way to explain the discrepancy between the empirical data and the predictions of the theory. An alternative way is to modify the theoretical postulates. Such a modification involves changing the old theory to a new theory. This continuity of theories in the methodology of science can be considered proceeding from Niels Bohr’s correspondence principle. A philosophical formulation of this principle was suggested by I. V. Kuznetsov, and later specified by Voishvillo. The implementation of the correspondence principle scheme is one of the necessary requirements for accepting a new theory. Thus, the failure of a new theory of this scheme is a formal reason to discard it. In my work, I apply this scheme to alternative theories of gravitation: Modified Newtonian dynamics (MOND) and tensor-vector-scalar gravity (TeVeS). I managed to show that MOND and TeVeS satisfy the principle of correspondence, therefore, they pass a methodological test.

DPC: You have been working with Finnish philosopher of science Ilkka Niiniluoto, who is known for his work in scientific realism and for explicating the notion of truthlikeness. What is the relevance of his ideas for your research?
A.L.: The basic idea of Niiniluoto's critical scientific realism is that science approximates reality. Scientific theories have always contained both truth and falsity in some sense, and generally the progress of science consists in adding true information and reducing false information. The better a theory approximates reality, the more truthlike it is. In contemporary philosophy this was first suggested by Karl Popper, but his approach (the content approach) has been proven to be formally insufficient. Niiniluoto's approach is known as the likeness approach, which is a mathematically well founded and exact way of comparing the truthlikeness of different theories relative to some concrete cognitive problem. An example of a cognitive problem in astrophysics is the functional relation of some physical quantities, such as the dependence between the distance of an object from the center of the galaxy and the rotational velocity of this object. I applied Niiniluoto’s method for evaluating the predictions of alternative theories: Modified Newtonian Dynamics (MOND) and standard cosmological model (Lambda-CDM). This was the first application of Niiniluoto’s method to contemporary physics. By assuming that our measurements of the relevant physical quantities are accurate, we can calculate the truthlikeness of various proposed theories relative to this cognitive problem.
We find that the predictions of Milgrom's Modified Newtonian Dynamics is more truthlike that the post hoc simulations of the Lambda-CDM regarding the dynamics of most galaxies.
This is a significant result in favor of MOND, which puts pressure on the proponents of Lambda-CDM to come up with a better model or to take MOND more seriously.

DCP: Could you give several examples of how philosophy affected contemporary cosmology and how contemporary cosmology (or physics in general) affected philosophy?
A.L.: It is well documented that Einstein greatly appreciated and used philosophical background theories in his work, particularly those concerning the methodology of physics (my specialty!). An example of this is his use of Mach's "historical-critical" analysis of the Newtonian dogma of absolute space. He also had vivid and fruitful correspondence with Mach, as well as other philosophers, like Cassirer, Schlick, Bergson and Reichenbach, and considered a philosophical attitude indispensable for a first-rate theoretical scientist. Sadly, most later 20th century physicists, at least in the West, were not so interested in the philosophical foundations and methodology of their discipline. In contemporary cosmology and astrophysics, on which my methodological research is focused, there are some signs of an increasing methodological awareness and explicit study and citation of philosophy of science. Usually, the people engaged in this pursuit are in this sense like Einstein, trying to find philosophical arguments against a widely held dogma that they think is poorly justified. Such people are currently in the minority, but I try to see it as a good opportunity for a philosopher like myself to do some work that can hopefully influence scientific practice.
In the other direction, the influence of physics on science is also well documented. That the geometry of the actual world is Non-Euclidian was an upsetting discovery, not just for many dogmatic scientists but also some  philosophers. Arguably, this inspired the third wave of positivism (i.e. logical positivism) that featured an epistemological suspicion against any unobservables featured in theories. Other aspects of general relativity and quantum mechanics also overthrew, or at least made questionable, several a priori principles of metaphysics, such as absolute simultaneity.

DPC: Recently we released an issue of the journal focused on the proofs of God’s existence. Inside this area the Big Bang theory is uses to support the cosmological argument for the existence of God. What do you think about this idea? 
A.L.: Al-Ghazali's (and later, William Lane Craig's) Kalam cosmological argument includes the premise that the universe had a beginning. The Big Bang theory, unlike steady state cosmology, may fit more naturally with this premise, but to say that it supports it is controversial. It is not clear that any information can travel across a singular boundary, i.e. from one side of the Big Bang singularity to the other side. This seems to predict that we will never know, on physical grounds, whether the universe really had a beginning or whether it already existed before the Big Bang. On the other hand, the fact that GR predicts an infinite value for a physical quantity, i.e. the infinitely dense Big Bang singularity, has been taken as a sign that GR is incomplete. So, even if we have good evidence that the universe is expanding, and thus was smaller, hotter and denser in the past, it might be better to be more agnostic about its properties during the time when the values of these quantities were so high that we can’t even understand the relevant physics.

DPC: Our spring issue will be devoted to the problem of personal identity, which is connected with the principle of individuation. In what form does this problem arise in physics and how is it usually solved?
A.L.: One question regarding personal identity is its survival over time. Identity is a transitive relation, so if A = B and A = C, then necessarily B = C. Now, we don't currently know which one (if any) interpretation of quantum mechanics is right, but let's assume the Many World interpretation by Hugh Everett is right. Then we can imagine a person A, who splits into person B and C as the multiverse keeps expanding. Intuitively, B and C are not identical. But if B and C are not identical, then how can B or C be identical to A? Everett saw this implication and claimed that the identity or non-identity is a matter of convention, because the intuition that B and C are not identical is based on viewing the life of a person as a line. But if the quantum multiverse is actually tree-like, then instead of thinking of the life or a person as a line, we should think of it too as a tree. Everett thought that the identity or non-identity of parallel individuals would then become a matter of convention. Of course, someone who objects to Everett's conclusion might think that this is actually an argument against the Many Worlds interpretation. I don't have any favorite interpretation of quantum mechanics yet, but I think it is interesting to see how they can have relevance for other fields of philosophical research.

Комментариев нет:

Отправить комментарий