Emergence in Materials

Emergence in Materials

May 25-27, IHPST Paris

13 rue du Four, Paris (metro stations: Mabillon or St. Germain de Pres)

For practical information, scroll to the end of this page.

The study of materials presents us with a range of phenomena, some of which are interesting also from a philosophical point of view. Many of these phenomena have been called “emergent”. They include phase transitions (Batterman 2002), superconductivity (Anderson 1972, Morrison 2012), ferromagnetism and antiferromagnetism (Cox and Pines 2005), the quantum Hall states (Laughlin and Pines 2000). From a theoretical standpoint, emergent phenomena have been associated with symmetry breaking (Anderson and Stein 1988, Anderson 2004), mathematical singularities (Berry 1994, Batterman 2002), multiple realizability (Cunningham 2001, Bedau 2008), computational irreducibility (Bedau 2008, Wolfram 1985).

This workshop aims to address the topic of emergent phenomena in materials. We aim to bring together scientists and philosophers to examine the various ways in which emergent phenomena can be said to occur in materials, and to discuss what features make these phenomena emergent. This conference will be a landmark for the nascent field of philosophy of materials science. It will help shape philosophy of materials science – one of the newest branches of philosophy of science – as a truly interdisciplinary field.

The workshop will take place at the IHPST (Institute for History and Philosophy of Science and Technology) in the center of Paris.

 

Tentative schedule:

May 25th

10:00-11:00 Thomas Vogt: Towards a philosophy of materials science
11:00-11:15 Coffee break
11:15-12:15 Margaret Morrison: Turbulent Flows, Universality and Emergence
12:15-2:00 Lunch (everyone on their own)
2:00-3:00 Jean-Pierre Llored: Chemical Materials and Emergence
3:00-3:15 Coffee break
3:15-4:15 Karim Thebault: The Hawking Effect as an Emergent Phenomenon?

May 26th

10:00-11:00 Alexandre Guay & Olivier Sartenaer: Emergent quasiparticles: the case of the fractional quantum Hall effect
11:00-11:15 Coffee Break
11:15-12:15 Alex Manafu: Piezoelectricity as an Emergent Property?
12:15-2:00 Lunch at the University Restaurant
2:00-3:00 Michael Berry: The singularities of light: intensity, phase, polarization
3:00-3:15 Coffee break
3:15-4:15 Sorin Bangu: When causation is not the point: Individualism v. Collectivism on Explanation
7:00pm Conference Dinner at Restaurant Bouillon Racine (3 Rue Racine, 75006 Paris)

May 27th

10:00-11:00 Shaul Katzir: Macro and microphysical explanations of piezoelectricity before WWII
11:00-11:15 Coffee break
11:15-12:15 Robert Batterman: Asymptotics, Minimal Models, Multiscale Techniques
12:15-2:00 Lunch at the University Restaurant
2:00-3:00 Olimpia Lombardi: From reduction to emergence: distinguishing between intratheory and intertheory emergence
3:00-3:15 Coffee break
3:15-4:15 Joachim Schummer: Material Emergence in Chemistry: The Standard Case

 

 

Titles and abstracts:

 

Sorin Bangu: When causation is not the point: Individualism v. Collectivism on Explanation

The distinction between causal v. non-causal explanations is a traditional one in the philosophy of science. Although intuitive enough, I suggest that it should be set aside, and the focus should be shifted on another distinction, between (what I call here) individualistic explanations v. collectivistic ones. The motivation for introducing this new distinction is the concern for the very reason of offering scientific explanations, namely achieving understanding (of a natural phenomenon). Thus, the claim is that such an understanding is, in many cases, not provided by an individualistic approach, but has to involve collectives (of entities), with the explanatory power originating in the demonstration of how the phenomenon emerges from its collective causal basis. Thus, although present in the background, the phenomenon’s causal basis is simply not the point of interest for an understanding-seeking explanation. A number of examples, some from materials science, will be discussed in order to support the main claim.

 

Robert Batterman: Asymptotics, Minimal Models, Multiscale Techniques

Much of applied mathematical modeling involves appeal to simple, “toy” or “minimal” models. A minimal model is one that “most economically caricatures the essential physics.” [N. Goldenfeld]  The requirement of economy is important and it is what allows one to draw (at least some) comparisons between various examples from across the sciences.  A paradigm instance is the Ising model.  I will discuss what justifies the use of such minimal models in statistical physics, materials science, and briefly in certain (developmental) biology contexts.

 

Michael Berry: The singularities of light: intensity, phase, polarization

Geometry dominates modern optics, in which we understand light through its singularities. These are different at different levels of description. The coarsest level is geometrical optics, where the singularities are caustics: focal lines and surfaces: the envelopes of ray families. These singularities of bright light are classified by the mathematics of catastrophe theory. Wave optics smooths these singularities and decorates them with rich and ubiquitous interference patterns. Wave optics also introduces phase, which has its own singularities. These are optical vortices, a.k.a nodes or wavefront dislocations. Geometrically these singularities of dark light are lines in space, or points in the plane. They occur in all types of quantum or classical waves. Incorporating the vector nature of light leads to polarization singularities, also geometrical, describing lines where the polarization is purely circular or linear. As well as representing physics at each level, these optical and wave geometries illustrate the idea of asymptotically emergent phenomena. The levels form a hierarchy, leading to predictions of new phenomena at the quantum level.

 

Shaul Katzir: Macro and microphysical explanations of piezoelectricity before WWII

In this talk I will discuss the ways physicists viewed and practice the relationships between the atomistic-molecular level and the phenomenological – macro level, and the possibility of explaining one by the other in the case of piezoelectricity before 1940. Molecular model of crystals led to discovery of the phenomenon in 1880. Yet, to account for the observations the researchers abandon the microscopic model for a phenomenological theory a decade later. Later molecular models were designed to deduce the laws of the macroscopic laws. Yet, they suggested only an imperfect kind of emergence for two main reasons: 1) they were speculative and built specifically to agree with piezoelectric theory; 2) leading concepts in those theories, like the molecular symmetry were inferred from the macro rather than the micro level. Later micro-physical explanation followed developments in the understanding of matter and molecules and had, therefore, the potential of showing how the macroscopic phenomena emerge from molecular structure. Yet, physicists employed macro-physical observations and rules in their suggestion of atomistic structure, including in spelling out a lattice structure of crystals based on x-rays diffraction techniques. Thus, although some physics believed that the lattice structure should explain piezoelectricity (and it partly did it in one case) in the methodology the microstructure followed the knowledge of macro-physical effects.

 

Jean-Pierre Llored: Chemical Materials and Emergence

Starting from the careful study of various chemical practices, the first part of the lecture highlights: (1) The mutual dependence of the levels of organization; (2) the codefinition of relations and relata; and (3) the constitutive role of the modes of intervention in the definition, always open and provisory, of chemical “individuals.” A return to the history of philosophy is then envisaged so as to study how the British emergentists connected chemistry with emergence. We then consider the formal definitions of emergence, and especially Kim’s work, by showing that the ceteris paribus clause on which all those (nomo)logical strategies rest takes another meaning within chemical metrology. In doing so, we stress the role and the importance of two kinds of mereology that enable us to think about emergence from a formal standpoint. We then widen and deepen our investigation by exploring how quantum chemists specifically negotiate a chemical whole, its parts, and the surroundings, within a calculation. A connection is eventually tried and opens several perspectives concerning emergence such as: (1) an ontological and pragmatic approach adapted from Peirce’s concept of habits or from Rom Harré’s affordances; (2) a relational king of emergence adapted to chemistry; and (3) a reconceptualization of the concept of emergence which addresses the consequences of the chemical bodies on humans and non-humans by integrating the pragmatic, socio-political, technological, and institutional conditions of chemical activities into the philosophical reflection about emergence.

 

Olimpia Lombardi: From reduction to emergence: distinguishing between intratheory and intertheory emergence.

I will begin by considering the problem of the relationship between physics and chemistry from the anti-reductionist perspective given by a Kantian rooted ontological pluralism. From this perspective I will analyze a neo-reductionist approach and its treatment of bridge laws, in particular those that do not express identity relations. This task will lead me to consider emergence and its essential features. On this basis, I will distinguish between intratheory emergence, in which the emergent and the base properties correspond to states defined in the context of the same theory, and intertheory emergence, which is a relationship between properties theoretically and empirically characterized in the context of different theories. I will accept the fist form of emergence but will argue against the second one from an ontological pluralist perspective.

 

Margaret Morrison: Turbulent Flows, Universality and Emergence

Turbulent flows are paradigm cases of complex systems where multi-scale modelling is required. The fundamental problems in the field are strong fluctuations and couplings – problems that are also present in condensed matter physics (CMP) and field theory. Like the latter two areas of physics, renormalization group methods have been used to treat some of the theoretical difficulties with turbulent flows. However, unlike CMP where universality is reasonably clearly understood, it is less than straightforward in cases of turbulence. I examine some of these issues in an attempt to clarify how we might understand emergence in the context of turbulent flows.

 

Olivier Sartenaer and Alexandre Guay: Emergent quasiparticles: the case of the fractional quantum Hall effect

In the proposed talk, we critically assess the claim that the fractional quantum Hall effect is a paradigmatic case – if not the case – of (a robust form of) emergence within physics itself. To this aim, we primarily explicate in which specific sense such an effect can be said to be emergent, and content that it can be considered as an instance of ontological, weak, diachronic emergence, a variety of emergence also recently called “transformational emergence”. We claim that such an account of emergence – together with a precise formal criterion to identify its empirical instances, a criterion suggested by topological Chern-Simons gauge theory – allows to account for the most striking features of the effect like, for example, the advent of new (quasi)particles – that are neither fermions nor bosons -, new “long-range” interactions, a new kind of order or a new phase of matter.

 

Joachim Schummer: Material Emergence in Chemistry: The Standard Case

In chemistry the emergence of new material phenomena and new materials is the rule rather than the exception. In fact, studying such emergences was for a long time a defining condition of chemistry, demarcating it from physics. That includes emergences both under changing composition and under changing thermodynamic, electromagnetic, and nuclear radiation conditions. The paper discusses epistemological and ontological implications of that standard view and asks whether recent examples of emergence in physics and materials science differ from that.

 

Karim Thébault: The Hawking Effect as an Emergent Phenomenon?

The Hawking effect is usually understood as a phenomenon predicted by semi-classical approaches to gravity when applied to astronomical black holes. The analogue acoustic phenomenon in condensed matter `dumb hole’ systems is then conceived of primarily as as potential means to `simulate’ gravitational Hawking radiation in the lab. Interesting questions arise, however, if we consider the potential `emergent’ status of the Hawking effect in the context of universality arguments. Here I will make use of the notion of an emergent phenomenon as a `novel and robust behaviour’, and set out two senses in which the Hawking effect might be considered emergent based upon robustness with respect to two different comparison classes. The first sense of emergence relates specifically to the Hawking effect in Bose-Einstein condensates, and is based upon the insensitivity of the Hawking flux to the breakdown of the hydrodynamical description at high frequencies. The second sense of emergence relates to the Hawking phenomenon in general, and is based upon robustness of the effect within systems that feature: i) a classical effective background and quantum field; and ii) some sort of horizon. While the first sense of emergence will be taken to be established straight-forwardly, the second will be found to be more problematic.

 

Thomas Vogt: Towards a philosophy of materials science

While efforts to develop a philosophy of chemistry have advanced over the past years important new concepts in materials science such as ‘quantum protectorates’ and emergent functionalities with multiple realizations point us to a new approach that permits emergent processes without abandoning physicalism. I will provide examples highlighting new developments in materials science that demonstrate the autonomy of chemistry and materials science.

 

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PRACTICAL INFORMATION

Workshop location

The workshop will take place at the IHPST, which is in the center of Paris. The address of the IHPST is: 13 rue du Four, Paris 75006. Map here The subway station closest to the IHPST is Mabillon (on line 10) or Saint-Germain-Des-Pres (on line 4). The entrance door is on the corner of the building (if you come with line 10, the door is one meter from the metro exit).

Some of the hotels where the participants in this workshop will be staying are within walking distance from the IHPST. Other hotels are some stations away, but still pretty close (by subway). To open the door and enter the building where the IHPST is located you need to push the big round button on the panel located at the entrance, to your right; this will open the door. The IHPST is at the third floor (or etage 2 by the French system/elevator). The door of the institute is marked “IHPST” . The workshop will take place in the Salle de Conference, immediately on your left as you enter the main door of the IHPST.

 

How to get from the Roissy Charles de Gaulle (CDG) Airport to the center of Paris

 The cheapest and easiest way to get from the CDG airport to Paris is by taking a subway train called RER B. The RER B departs right from the airport and it gets you to the center of Paris. It takes about 40-50 minutes. After you get off the plane, look for RER B indicators in the airport. They look like this:

In the airport, before you get on the escalator and descend to the RER B station, there is a lobby where you can find automated ticket machines and also an information desk. Subway employees wearing red are often there to help. A ticket to Paris for the RER B costs about 9.75 euros. Cabs are much more expensive (50-70 euros or even more).

The RER B stations in the Latin Quarter (i.e., the center of Paris where the Sorbonne and the IHPST are located) are: Saint-Michel-Notre-Dame and Luxembourg.  The subway station closest to the IHPST is Mabillon (on line 10) or Saint-Germain-Des-Pres (on line 4).

Here’s the website of the Paris public transit system: http://www.ratp.fr/en/

 

Registration

If you would like to attend the workshop please send an email with the subject “workshop registration” stating your name, position and institutional affiliation to alexmanafu*gmail.com (replace * by you know what sign). Note that the number of seats is limited and we might not be able to accommodate everyone.

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