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Silk is a semidilute solution of randomly coiled associating polypeptide chains that crystallize following the stretch-induced disruption, in the strong extensional flow of extrusion, of the solvation shell around their amino acids. We propose that natural silk spinning exploits both the exponentially broad stretch distribution generated by associating polymers in extensional flow and the criterion of a critical concentration of sufficiently stretched chains to nucleate flow-induced crystallization. To investigate the specific-energy input needed to reach this criterion in start-up flow, we have coupled a model for the Brownian dynamics of a bead-spring-type chain, whose beads represent coarse-grained Gaussian chain segments, to the stochastic, strain-dependent binding and unbinding of their associations. We have interpreted the simulations with the aid of analytic calculations on simpler, tractable models with the same essential physical features. Our simulations indicate that the associations hamper chain alignment in the initial slow flow, but, on the other hand, facilitate chain stretching at low specific work at later, high rates. We identify a minimum in the critical specific work at a strain rate just above the stretch transition (i.e., where the mean stretch diverges), which we explain in terms of analytical solutions of a two-state master equation. We further discuss how the silkworm appears to exploit the chemical tunability of the associations to optimize chain alignment and stretching in different locations along the spinning duct: this delicate mechanism also highlights the potential biomimetic industrial benefits of chemically tunable processing of synthetic association polymers.

A personal recollection of gratitude reports on the way that the writings of John Polkinghorne inspired and guided the author’s own thinking in science and theology since meeting him as a graduate student. Themes of both agreement and disagreement are selected from the many to be found in Polkinghorne’s corpus. Closer attention is paid to two of his books, Science and Christian Belief and Faith, Science and Understanding. A running theme is the creative tension of a ‘bottom-up thinker’, one of whose salient and influential arguments was that of ‘top-down causation’. Although there is disagreement over Polkinghorne’s exegesis of divine character in Job, thinking the argument through did bear fruit.

In his treatise On the Rainbow (De iride), composed nearly four hundred years before the first known telescope, the English polymath Robert Grosseteste identified three striking optical effects: distant objects can be rendered close by; close-by large objects can be rendered small; and distant small objects can be rendered large. In the context of the history of optics, the first effect is especially striking. Grosseteste did not give details of the mechanisms underlying these effects but did mention the passage of rays through refraction in “diaphanous” or transparent bodies. While making no final claim that Grosseteste himself necessarily knew of or used lenses, this essay examines the coherence between the three optical effects described in Grosseteste’s treatise and two candidate proposals for the deployment of a single convex lens. A convex lens, deployed in different ways, is shown to produce all three of Grosseteste’s optical effects, in a manner strikingly aligned with the language that he uses to distinguish changes in the location and size of objects. The implications of this coherence for interpretations of On the Rainbow are discussed throughout the essay.

Changes in the structural dynamics of double stranded (ds)DNA upon ligand binding have been linked to the mechanism of allostery without conformational change, but direct experimental evidence remains elusive. To address this, a combination of steady state infrared (IR) absorption spectroscopy and ultrafast temperature jump IR absorption measurements has been used to quantify the extent of fast (∼100 ns) fluctuations in (ds)DNA·Hoechst 33258 complexes at a range of temperatures. Exploiting the direct link between vibrational band intensities and base stacking shows that the absolute magnitude of the change in absorbance caused by fast structural fluctuations following the temperature jump is only weakly dependent on the starting temperature of the sample. The observed fast dynamics are some two orders of magnitude faster than strand separation and associated with all points along the 10-base pair duplex d(GCATATATCC). Binding the Hoechst 33258 ligand causes a small but consistent reduction in the extent of these fast fluctuations of base pairs located outside of the ligand binding region. These observations point to a ligand-induced reduction in the flexibility of the dsDNA near the binding site, consistent with an estimated allosteric propagation length of 15 Å, about 5 base pairs, which agrees well with both molecular simulation and coarse-grained statistical mechanics models of allostery leading to cooperative ligand binding.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which caused the COVID-19 pandemic, has no vaccine or antiviral drugs available to the public, at the time of writing. The virus’ non-structural proteins are promising drug targets because of their vital role in the viral cycle. A significant body of work has been focused on finding inhibitors which covalently and competitively bind the active site of the non-structural proteins, but little has been done to address regions other than the active site, i.e. for non-competitive inhibition. Here we extend previous work on the SARS-CoV-2 Mpro (nsp5) to three other SARS-CoV-2 proteins: host shutoff factor (nsp1), papain-like protease (nsp3, also known as PLpro) and RNA-dependent RNA-polymerase (nsp12, also known as RdRp) in complex with nsp7 and nsp8 cofactors. Using open-source software (DDPT) to construct Elastic Network Models (ENM) of the chosen proteins we analyse their fluctuation dynamics and thermodynamics, as well as using this protein family to study convergence and robustness of the ENM. Exhaustive 2-point mutational scans of the ENM and their effect on fluctuation free energies suggest several new candidate regions, distant from the active site, for control of the proteins’ function, which may assist the drug development based on the current small molecule binding screens. The results also provide new insights, including non-additive effects of double-mutation or inhibition, into the active biophysical research field of protein fluctuation allostery and its underpinning dynamical structure.

Soft Matter: A Very Short Introduction explores the field of soft matter, looking beneath the appearances of matter into its inner structure. Drawing on physics, chemistry, mathematics, and engineering, soft matter science links fundamental scientific ideas to everyday phenomena such as ‘inkiness’ and ‘stickiness’, with a rich history and philosophy. It studies materials such as polymers, colloids, liquid crystals, and foams. This VSI shows how Brownian Motion—the random molecular motion underlying ‘heat’—is an underpinning principle of soft matter. From hair conditioners to honey, it discusses how common characteristics of these materials shape their behaviour and applications.

‘Pearliness’ focuses on the soft matter class of ‘liquid crystals’ and considers a new ‘phase’ of matter: the ‘nematic’ state. The liquid crystal molecules are built of many atoms; they are mesoscopic objects. Their essential structure lies therefore in their overall rod-like shape, not in their specific atomistic constituents. In consequence, nematic behaviour is universal—there are many examples of molecules which form a nematic state. How do ideas from superconductivity and particle physics theory provide a conceptual framework for the theoretical physics of liquid crystals? There is another class of liquid crystals known as ‘smectic’ which are important to consider in this topic.

‘Milkiness, muddiness, and inkiness’ discusses the phenomena of ‘muddiness’ and ‘inkiness’, which are both examples of ‘colloids’—the fundamental class of soft matter constituted by dispersing very small particles of solid matter in a liquid environment. The colloidal state provided the final evidence that atoms existed. Michael Faraday gave a well-known lecture on the ‘Brownian Motion’ and he also researched gold colloids which show how small particles disperse. Albert Einstein came up with a theory of thermal noise, and Charles Perrin carried out a famous experiment in 1908 on this topic. Both Einstein and Perrin showed that colloidal particles can do everything that molecules do, but at a thousand times the size, and equally more slowly.

‘Liveliness’ studies the new biologically inspired field of active soft matter. Almost any type of soft matter possesses an active form. Using myosin corresponds to making the cross-links of a polymer gel active. However, polymerization itself can be actively driven, as well as the cross-linking between polymers. Bacteria are, within this perspective, an active form of colloid—nanoparticles that can swim. As their shape becomes highly anisotropic, they generate the notion of ‘active liquid crystals’.

‘Gelification and soapiness’ looks at the third class of soft matter: ‘self-assembly’. Like the colloids of inks and clays, and the polymers of plastics and rubbers, ‘self-assembled’ soft matter also emerges as a surprising consequence of Brownian motion combined with weak intermolecular forces. Like them, it also leads to explanations of a very rich world of materials and phenomena, such as gels, foams, soaps, and ultimately to many of the structures of biological life. There is an important distinction that needs to be made between one-dimensional and two-dimensional self-assembly.

‘Sliminess and stickiness’ examines the molecular origin of ‘stickiness’. It details Hermann Staudinger’s research on ‘double bonds’ and ‘macromolecules’. Understanding the unorthodox properties of the polymer liquid and gel state turned out to be one of the first successes of soft matter science. Staudinger faced a challenge: how much space would a polymer molecule occupy when in solution? Many of the mathematical techniques that had been developed to deal with the quantum mechanics of electrons, photons, and their interaction in solids could be translated into tools for solving polymer problems such as this one. The properties of rubber, and the sticky sliminess of rubbery liquids, are topics which relate to the notion of stickiness.

‘The science of softness’ provides a brief history and overview of soft matter science. The development of soft matter science was propelled by a combination of communication within the scientific community; intrinsic conceptual overlap and commonality; and visionary leadership from a small number of pioneering scientists. Chemistry proved as essential an ingredient to the new science of soft matter as ideas and techniques from physics. The characteristics of soft matter include motion; structure on intermediate length scales; slow dynamics; and universality. Microscopy is the most obvious and direct example of experimental tools applied across the gamut of soft materials.

The Conclusion looks at the topics that haven't been covered in this VSI. There is so much more to the topic to be learnt: recent developments in rheology at the single molecule level through atomic force microscopy, and the single polymer imaging of confocal microscopy to name but a few. It is an undisputed truth that, through evolution, life itself has recruited the structures of soft matter for its own purposes. Polymers, membranes, liquid crystallinity, self-assembly form its fundamental constituents, from the humblest bacterium to the most complex multicellular creature. The tree of life has taken these materials and combined them in vast complexities of such intricacy that the student of simple systems is easily bewildered by the questions of life.

We consider the polymer physics of a possible molecular mechanism for disentangled melt states observed recently. We find that the route from molten, but only marginally-overlapping single crystals to the equilibrium state must pass over a free-energy barrier that becomes large at high molecular weights. The penalty arises from elastic distortions of the entanglement network as the chains diffuse. A critical molecular weight arises naturally from the competition of elastic distortion and the free-energy of confinement. We calculate the barrier and critical molecular weight at both a simple single-chain level, and at a “one-loop” level of co-operative motion, finding that many-chain effects alter the physics quantitatively, but not qualitatively. Several new experiments are suggested.

The metaphor of nature as a book, and its reading, has arisen in many forms in theological discussions of natural philosophy from ancient to modern periods. It is far less fixed in form than often assumed, however, but reflects cultural contextual shape. It is also too often recruited without challenge, although the implied analogies of authorship, narrative shape, and hermeneutic contain many pitfalls. I explore four flaws in the ‘Book of Nature’ narrative, finding that they are connected with two related and troublesome tensions – that of ‘methodological naturalism’ within a theistic framework, and the redundancy of ‘natural theology’ in its nineteenth century form. Approaching a theology of science from the perspective of the Wisdom tradition offers a fresh conception of who does the writing, and reading, of nature’s living book.

Spontaneous liquid-liquid phase separation is commonly understood in terms of phenomenological mean-field theories. These theories correctly predict the structural features of the fluid at sufficiently long time scales and wavelengths. However, these conditions are not met in various examples in biology and materials science where the mixture is slowly destabilised, and phase separation takes place close to the critical point. Using kinetic Monte Carlo and molecular dynamics simulations of a binary surface fluid under these conditions, we show that the characteristic length scale of the emerging structure decreases, in 2D, with the 4/15 dynamic critical exponent of the quench rate rather than the mean-field 1/6th power. Hence, the dynamics of cluster formation governed by thermodynamically undriven Brownian motion is much more sensitive on the rate of destabilisation than expected from mean-field theory. We discuss the expected implications of this finding to 3D systems with ordering liquid crystals, as well as phase-separating passive or active particles., Comment: 8 pages, 9 figures

This historical paper examines a pioneering theory of speech production and perception from the thirteenth century. Robert Grosseteste (c.1175—1253) was a celebrated medieval thinker, who developed an impressive corpus of treatises on the natural world. This paper looks at his treatise on sound and phonetics, De generatione sonorum [On the Generation of Sounds]. Through interdisciplinary analysis of the text, this paper finds a theory of vowel production and perception that is notably mathematical, with a formulation of vowel space rooted in combinatorics. Specifically, Grosseteste constructs a categorical space comprising three fundamental types of movements pertaining to the vocal apparatus: linear, circular, and dilational-constrictional; these correspond to similarity transformations of translation, rotation, and uniform scaling, respectively. That Grosseteste's space is categorical, and low-dimensional, is remarkable vis-a-vis current theories of phoneme perception. As well as his description of vowel space, Grosseteste also sets out a hypothetical framework of multisensory integration, uniting the production, perception, and representation in writing of vowels with a set of geometric figures associated with “mental images.” This has clear resonances with contemporary studies of motor facilitation during speech perception and audiovisual speech. This paper additionally provides an experimental foray, illustrating the coherence of mathematical and scientific thinking underpinning this early theory.

Allosteric regulation plays an important role in many biological processes, such as signal transduction, transcriptional regulation, and metabolism. Allostery is rooted in the fundamental physical properties of macromo-lecular systems, but its underlying mechanisms are still poorly understood. A collection of contributions to a recent interdisciplinary CECAM (Center Européen de Calcul Atomique et Moléculaire) workshop is used here to provide an overview of the progress and remaining limitations in the understanding of the mechanistic foundations of allostery gained from computational and experimental analyses of real protein systems and model systems. The main conceptual frameworks instrumental in driving the field are discussed. We illustrate the role of these frameworks in illuminating molecular mechanisms and explaining cellular processes, and describe some of their promising practical applications in engineering molecular sensors and informing drug design efforts.

Personal accounts of the creative process in science tell us that there is no ‘method’ to the conception of a new scientific idea. Stories from physicist Richard Feynman, the author’s own scientific experience, an example of physics and biology working together, and a conversation of scientists assembled in Cambridge by The Imagination Institute, all give different accounts of the ways that imagination can play out in science. Themes emerge from these raw accounts that will shape the subsequent chapters: especially the experienced typology of imagination into visual, textual and abstract forms. The subtle interaction of conscious and non-conscious thought raises questions of the link between cognition and aesthetic response in mental creative acts.

The third mode of imagination is the abstract—the world shared by mathematics and music. Once held together in the ‘quadrivum’ of medieval liberal arts, they have now lost their obvious connection. This chapter explores their deeper commonalities, starting with Andrew Wiles’ proof of Fermat’s last theorem, and Shostakovich’s eighth string quartet, the shared role of number in rhythm, volume, and pitch leads to a deeper world of multi-layered structure and the unconscious imagination. The writing of, and writing about music of Robert Schumann, including a detailed examination of his Konzertstück for four horns and orchestra, is contrasted with writing about mathematical creativity by Hadamard. The collision of beauty, structure, and universality is illustrated by a close encounter with the Fluctuation–Dissipation Theorem. In both cases of mathematics and music, notation is explicitly displayed in an exploration of how it serves as an extension to imaginative thought.

This first chapter surveys the landscape of the book, and the questions it will seek to explore. By listening to the verbal associations we bring to arts and to science, we observe that one reason for the differences is that artists and scientists are private and public about different aspects of their work. Science only speaks of the creative, inspirational moments, more familiar in the arts, in hushed tones, while artists are less forthcoming about the arduous journey from concept to creation through experiment, trial, and error, an essential process closely shared with science. By listening to Einstein, Shakespeare, Wordsworth, Keats, and the biblical Book of Job, we conceive of the commonality of imagination within constraint that connects the work of art and science alike.

‘I could not see any place in science for my creativity or imagination’, was the explanation, of a bright school leaver to the author, of why she had abandoned all study of science. Yet as any scientist knows, the imagination is essential to the immense task of re-creating a shared model of nature from the scale of the cosmos, through biological complexity, to the smallest subatomic structures. Encounters like that one inspired this book, which takes a journey through the creative process in the arts as well as sciences. Visiting great creative people of the past, it also draws on personal accounts of scientists, artists, mathematicians, writers, and musicians today to explore the commonalities and differences in creation. Tom McLeish finds that the ‘Two Cultures’ division between the arts and the sciences is not after all, the best classification of creative processes, for all creation calls on the power of the imagination within the constraints of form. Instead, the three modes of visual, textual, and abstract imagination have woven the stories of the arts and sciences together, but using different tools. As well as panoramic assessments of creativity, calling on ideas from the ancient world, medieval thought, and twentieth-century philosophy and theology, The Poetry and Music of Science illustrates its emerging story by specific close-up explorations of musical (Schumann), literary (James, Woolf, Goethe) mathematical (Wiles), and scientific (Humboldt, Einstein) creation. The book concludes by asking how creativity contributes to what it means to be human.

The book finishes with an examination of the human purpose of creativity and creation. The evidence and narrative gathered so far is summarized in a ‘creation narrative’—a basic story of the emotional and cognitive trajectory of the creative process. Drawing on recent work in anthropology, narratology, and theology, and on phenomenological philosophy of the human condition, the chapter develops the thesis that creativity of all kinds contributes to a healing of a broken or incomplete human relationship with the world. The story of our growing understanding of the rainbow acts as an illustration of the extreme length, but great human depth, of this process.

The dual roles of cognition and emotion in creativity that have emerged at many points in the book so far are examined in their own right. Through the lens of medieval philosophy, especially the work of Robert Grosseteste, then Kant, Spinoza, Hume, and the recent study of Iain McGilchrist, this chapter examines the structure of how the affective works in the origination of ideas, not just in response to them. Contemporary scientific testimony to the creative function of emotion leads to a detailed case study of a Caltech project to develop a polymer additive to make jet fuel safe in crashes, and other stories of scientific creation, earth the philosophical discussion in experience.

The first mode of imagination—the visual—is shared by art and science. The chapter starts with an account of the history of visual perception, working though the ancient theory of ‘extramission’, because it sheds light on the role of the mind’s active projection of visual impressions on the world in the interpretation of incoming images. The commonality of scientific and artistic visual imagination is partially to be found in mappings between spaces of three to two dimensions, exemplified perfectly by astronomy, and the work of medieval painter Giotto. Comparisons of the creative process in a recent astrophysical discovery are made with a contemporary artist (Graeme Willson) and through a detailed study of a lesser-known work by Monet.

The coincident birth of experimental science and the early English novel is followed to its underlying rationale of mimesis—the construction of small, abstracted worlds in which possibilities and constraints play out and which teach us about the wider world. The second mode of imagination is the textual. The entangled story of the textual in literature and science is followed though Newton and Milton, Boyle and Defoe, Humboldt and Emerson, and a parallel reading of Henry James’ The Art of the Novel and William Beveridge’s The Art of Scientific Investigation. Late-modern comparisons are made between Feynman’s Nobel Prize account, and the writing of Nabokov and Woolf, finding that textual imagination still displays common creative patterns in science and literature.

In this chapter, I will challenge a common background relational assumption behind all of Barbour’s categories as intrinsically unfaithful to the universal nature of both science and religion, arguing instead that it is more fruitful to ask what a ‘theology of science’ might look like. ‘What does science do, and what is it for, within a theological worldview?’ This approach works very well in a teaching context when developed in two ways: (1) historically and (2) using Biblical studies in wisdom, especially in the book of Job. Students of this approach start to think in new ways and ask new questions, suggesting an approach to science or in its more ancient form natural philosophy – the ‘love of wisdom of natural things’ – that can draw on theological and cultural roots. I suggest that deriving a human narrative for science in this way can transform the way political discussions of ‘troubled technologies’ (genetic medicine, genetically modified organisms (GMOs), fracking, etc.) are framed and the way we approach science in education and the media.

Medium or large amplitude oscillatory shear (M/LAOS) is sensitive to polymer chain structure, yet poses unsolved challenges for 'a priori' structural characterisation. In this letter, we present a MAOS protocol applied to near-monodisperse linear polymer melts, from which chain-stretch relaxation, a key structural feature, is clearly discernible. The third harmonics of MAOS frequency sweeps are decomposed into real and imaginary components and found to obey time-temperature superposition. The GLaMM molecular tube-based model of linear entangled melt rheology and structure, which has no free parameters, closely follows the form of our experimental results for the third harmonics and contains discriminatory features which depend only on the polymer's chain stretch relaxation time. Significantly, these third harmonic features occur at low frequency and are readily accessible with standard rheometers. For materials where phase transitions restrict the use of time temperature superposition, this method greatly increases the scope of rotational rheometry for structural analysis of polymers. Although the theory shows good qualitative agreement with experimental data, we find fundamental differences in magnitude and the frequency dependence of the third harmonics which must be resolved in order to fully understand the molecular basis of the stress response., Comment: V2 - Accepted version: 6 main pages with 4 figures + 8 supplemental pages with 8 figures

Using the simple ‘allosteron’ model, we show that it is possible, in principle, to elicit pathways by which fluctuation allostery affects self-assembly of protein complexes. We treat the cases of (i) protein fibrils and nucleation, (ii) n -mer protein complexes, and (iii) weakly attractive allosteric interactions in protein-like soft nanoscale objects that can be tuned to define exclusive self-associating families. This article is part of a discussion meeting issue ‘Allostery and molecular machines’.

We examine the contrast between mechanisms for allosteric signaling that involve structural change, and those that do not, from the perspective of allosteric pathways. In particular we treat in detail the case of fluctuation-allostery by which amplitude modulation of the thermal fluctuations of the elastic normal modes conveys the allosteric signal, and address the question of what an allosteric pathway means in this case. We find that a perturbation theory of thermal elastic solids and nonperturbative approach (by super-coarse-graining elasticity into internal bending modes) have opposite signatures in their structure of correlated pathways. We illustrate the effect from analysis of previous results from GlxR of Corynebacterium glutamicum, an example of the CRP/FNR transcription family of allosteric homodimers. We find that the visibility of both correlated pathways and disconnected sites of correlated motion in this protein suggests that mechanisms of local elastic stretch and bend are recruited for the purpose of creating and controlling allosteric cooperativity.

This paper describes the theoretical prediction, finite element simulation, and experimental studies of extrudate swell in monodisperse and bidisperse polystyrenes. We present a molecular approach to understanding extrudate swell using the tube-model-based Rolie-Poly constitutive equation within a Lagrangian finite element solver. This yields theoretical predictions of swelling which show a close universality: The molecular weight dependence of the swelling can be removed when the flow speed is scaled by the Rouse Weissenberg number. The roles that both chain orientation and stretch play in determining extrudate swell are clearly identifiable from plots of swelling ratio against each Weissenberg number. We also present isothermal extrusion experiments on the same polymers and can obtain good predictions well into the strong chain stretching regime. The predictions for swelling ratios match those from experiments up to Rouse Weissenberg numbers of ∼7, above which swelling is overpredicted by the Rolie-Poly equation.

In a recent short communication [Read, D. J. et al., Science 333, 1871 (2011)], we showed that a computational scheme can describe the nonlinear flow properties for a series of industrial low-density polyethylene (LDPE) resins starting from the molecular architecture. The molecular architecture itself is determined by fitting parameters of a reaction kinetics model to average structural information obtained from gel-permeation chromatography and light scattering. Flow responses of these molecules in transient uniaxial extension and shear are calculated by mapping the stretch and orientation dynamics of the segments within the molecules to effective pom-pom modes. In this paper, we provide the details of the computational scheme and present additional results on a LDPE and a high-density polyethylene resin to illustrate the dependence of segmental maximum stretch variables on the flow rate.

The fact that allostery, a nonlocal signaling between distant binding sites, can arise mainly from the entropy balance of collective thermal modes, without conformational changes, is by now well known. However, the propensity to generate negative cooperativity is still unclear. Starting from an elastic-network picture of small protein complexes, in which effector binding is modeled by locally altering interaction strengths in lieu of adding a node-spring pair, we elucidate mechanisms particularly for such negative cooperativity. The approach via a few coupled harmonic oscillators with internal elastic strengths allows us to trace individual eigenmodes, their frequencies, and their statistical weights through successive bindings. We find that the alteration of the oscillators’ couplings is paramount to covering both signs of allostery. Binding-modified couplings create a rich set of eigenmodes individually for each binding state, modes inaccessible to an ensemble of noninteracting units. The associated shifts of collective-mode frequencies, nonuniform with respect to modes and binding states, result in an enhanced optimizability, reflected by a subtle phase map of allosteric behaviors.The fact that allostery, a nonlocal signaling between distant binding sites, can arise mainly from the entropy balance of collective thermal modes, without conformational changes, is by now well known. However, the propensity to generate negative cooperativity is still unclear. Starting from an elastic-network picture of small protein complexes, in which effector binding is modeled by locally altering interaction strengths in lieu of adding a node-spring pair, we elucidate mechanisms particularly for such negative cooperativity. The approach via a few coupled harmonic oscillators with internal elastic strengths allows us to trace individual eigenmodes, their frequencies, and their statistical weights through successive bindings. We find that the alteration of the oscillators’ couplings is paramount to covering both signs of allostery. Binding-modified couplings create a rich set of eigenmodes individually for each binding state, modes inaccessible to an ensemble of noninteracting units. The associated shi...

In this article the investigators of the Ordered Universe project will reflect on how a diverse range of disciplinary perspectives essential for effective research into medieval science have been identified, acknowledged and absorbed into a genuinely interdisciplinary methodology. The project operates with a radical interdisciplinary composition bridging science and humanities in particular. How to translate what might be termed current academic practices and expectations between disciplines and between colleagues is a key issue. The article explores the practices of collaborative discussion, collaborative reading and collaborative writing. Central to these issues is the notion of the “atmosphere of enquiry”: getting the best from disciplinary perspectives, respecting expertise and having the right to challenge disciplinary boundaries are integral elements within the process. Finally the experience of this project is set in the context of the wider discussion of what interdisciplinary research means. We discuss how the methods of the Ordered Universe might be used, by imitation or by analogy. This article is published as part of a collection on interdisciplinarity.

It has been a long held ambition of both industry and academia to understand the relationship between the often complex molecular architecture of polymer chains and their melt flow properties, with the goal of building robust theoretical models to predict their rheology. The established key to this is the use of well-defined, model polymers, homogeneous in chain length and architecture. We describe here for the first time, the in silico design, synthesis, and characterization of an architecturally complex, branched polymer with the optimal rheological properties for such structure-property correlation studies. Moreover, we demonstrate unequivocally the need for accurate characterization using temperature gradient interaction chromatography (TGIC), which reveals the presence of heterogeneities in the molecular structure that are undetectable by size exclusion chromatography (SEC). Experimental rheology exposes the rich pattern of relaxation dynamics associated with branched polymers, but the ultimate test is, of course, did the theoretical (design) model accurately predict the rheological properties of the synthesized model branched polymer? Rarely, if ever before, has such a combination of theory, synthesis, characterization, and analysis resulted in a "yes", expressed without doubt or qualification.