![]() Selected sentences from this rich discussion will have to suffice here. Molecules merge to form proteins, proteins merge to carry out organic functions, functional parts converge to form organs, neural cells form brains, brains merge to create mass behavior, language, ideas, cities, the Web.įinally, Goodenough and Deacon describe the place of emergence in the view of nature and biology as sacred. The whole point of life is to generate emergent properties that, if successfully executed, have the additional feature of permitting transmission of genomes.” It is the organism and its emergent properties that must survive and reproduce if the genome is to make it through to the next generation.Īs organic entities increase in number and complexity, examples of emergence abound. “Genomes are in fact the handmaidens of emergent properties, not the other way around…. Goodenough and Deacon emphasize, interestingly, that it is not this coded recipe, the genome, that is driving the system. Energy (food) would be needed, along with an internal recipe for the proper sequence (DNA), and a living things could emerge. At that point a cycle was created, the basis of the self-sustaining quality that is characteristic of life. The pivotal moment, according to Goodenough and Deacon, occurred when the sequence happened to create over again one of the first chemicals in its chain. In the same way, a sequence of atoms, molecules and complex compounds, merging and emerging one from the other, may have created life. When, in turn, two or more water molecules come together, they again display characteristics as a solid, liquid, or gas that the single water molecule doesn’t possess. Two gasses merge to form a very different molecule of water. Emergence, in contrast, runs the movie forwards to show atoms forming compounds which then form structures, and even how life may have begun and developed. In short, as the authors put it, reductionism is running the movie backwards. Though it tells us much about what a substance is made of, reductionism tells us little about how the parts came together in the first place and how properties emerged. Goodenough and Deacon emphasize that emergence is the counterpart of reductionism, the process of breaking entities down into their parts. The common example is water: it combines hydrogen and oxygen but is like neither of those gases. Emergence occurs when a combination of entities has characteristics that are unlike the characteristics of its components. The adage that “the whole is more than the sum of the parts” conveys a rough idea of the principle of emergence. As the title suggests, the authors not only describe emergence but also discuss its place in the perspective of religious naturalists. So a helpful source that I will summarize here has been “The Sacred Emergence of Nature” by Ursula Goodenough and Terrence Deacon (2008). But apart from the obvious sense that something arises, the meaning of the term-and what the excitement is all about-haven’t been clear to me. They can be applied to any phase separated system to probe regions resistively hidden to transport measurements.I’ve been seeing the word emergence more and more in the last few years. While the manganites will be the primary focus throughout this dissertation, the spatial confinement techniques presented here are not limited to only these materials. This has led to observations of several new phenomena such as a reemergent metal-insulator transition, ultra-sharp jumps in resistivity at the metal-insulator transition, and the first high resolution observation of single domain electronic phase transitions in the time domain. Unlike transport measurements done on bulk or thin films where the electrons follow only the metallic path of least resistance, this configuration forces electrons to travel through both the metallic and insulating regions residing in the material. I reduce single crystal thin films of an electronically phase separated manganite to the scale of their inherent electronic phase domains near the metal-insulator transition. The purpose of my research is to answer fundamental questions about the specific role of PS in complex oxides. However there is debate as to its precise role. This phase separation (PS) is of particular interest, as it has been suggested that it is the central feature that leads to CMR in manganites, the Mott transition in VO 2 and may play a role in high-TC superconductivity in cuprates. There is evidence that alloyed single crystal materials in this class can display electronic inhomogeneity in which areas with vastly different electronic and magnetic properties can form and coexist in phase separated domains ranging in size from a few nanometers to micrometers. Rare earth manganites exhibit colossal magnetoresistance (CMR).
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