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- It described how electronic and assorted chemical waste dumped into a pond begins to organize itself into a neural net.
- I recommend this intriguing novel in spite of its few shortcomings. The central idea is fascinating.
And here comes the latest news on how 'lifeless stuff' behaves like living matter.
Physicists at Emory University have shown how a system of lifeless particles can become "life-like" by collectively switching back and forth between crystalline and fluid states -- even when the environment remains stable.
Physical Review Letters recently published the findings, the first experimental realization of such dynamics.
"We've discovered perhaps the simplest physical system that can consistently keep changing behavior over time in a fixed environment," says Justin Burton, Emory assistant professor of physics. "In fact, the system is so simple we never expected to see such a complex property emerge from it."
Many living systems -- from fireflies to neurons -- switch behaviors collectively, firing on and then shutting off. The current paper, however, involved a non-living system: Plastic particles, tiny as dust specks, that have no "on" or "off" switches.
"The individual particles cannot change between crystalline and fluid states," Burton says. "The switching emerges when there are collections of these particles -- in fact, as few as 40. Our findings suggest that the ability for a system to switch behaviors over any time scale is more universal than previously thought."
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This article appeared on Science Daily
https://www.sciencedaily.com/releases/2017/11/171102124927.htm
Story Source:
Materials provided by Emory Health Sciences. Original written by Carol Clark. Note: Content may be edited for style and length.
Contrary to what his colleagues thought, Ilya Prigogine was convinced that life arose out of chaos. He saw signs of this in the Bernard Instability, which occurs when a liquid is heated from below.
The Burton lab studies the tiny, plastic particles as a model for more complex systems. They can mimic the properties of real phenomena, such as the melting of a solid, and reveal how a system changes when it is driven by forces.
The particles are suspended in a vacuum chamber filled with a plasma -- ionized argon gas. By altering the gas pressure inside the chamber, the lab members can study how the particles behave as they move between an excited, free-flowing state into a jammed, stable position.
The current discovery occurred after Emory graduate student Guram "Guga" Gogia tapped a shaker and slowly "salted" the particles into the vacuum chamber filled with the plasma, creating a single layer of particles levitating above a charged electrode.
"I was just curious how the particles would behave over time if I set the parameters of the chamber at a low gas pressure, enabling them to move freely," Gogia says. "After a few minutes I could see with my naked eye that they were acting strangely."
From anywhere between tens of seconds to minutes, the particles would switch from moving in lockstep, or a rigid structure, to being in a melted gas-like state. It was surprising because the particles were not just melting and recrystallizing but going back and forth between the two states.
"Imagine if you left a tray of ice out on your counter at room temperature," Gogia says. "You wouldn't be surprised if melted. But if you kept the ice on the counter, you would be shocked if it kept turning back to ice and melting again."
Gogia conducted experiments to confirm and quantify the phenomenon. The findings could serve as a simple model for the study of emerging properties in non-equillibrium systems.
"Switching is an ubiquitous part of our physical world," Burton says. "Nothing stays in a steady state for long -- from Earth's climate to the neurons in a human brain. Understanding how systems switch is a fundamental question in physics. Our model strips away the complexity of this behavior, providing the minimum ingredients necessary. That provides a base, a starting point, to help understand more complex systems."
This article appeared on Science Daily
https://www.sciencedaily.com/releases/2017/11/171102124927.htm
Story Source:
Materials provided by Emory Health Sciences. Original written by Carol Clark. Note: Content may be edited for style and length.
Journal Reference:
- Guram Gogia, Justin C. Burton. Emergent Bistability and Switching in a Nonequilibrium Crystal. Physical Review Letters, 2017; 119 (17) DOI: 10.1103/PhysRevLett.119.178004
RELATED
PHYSICS AND BALLET - And how PHYSICS can teach us lessons for a happier personal life
There is hidden life lesson in the following excerpt from the book Beyond the Quantum (page 135). To know what it is, just click on this link:
Contrary to what his colleagues thought, Ilya Prigogine was convinced that life arose out of chaos. He saw signs of this in the Bernard Instability, which occurs when a liquid is heated from below.
As the temperature rises, at a certain point molecules in the liquid suddenly "self-organize," arranging themselves in hexagonal cells resembling stained glass windows.
In the late sixties Russian biophysicist Anatoli Zhabotisnky discovered that when certain chemical substances were mixed together in a liquid state, instead of becoming murky and dispersed, they oscillated back and forth with clocklike precision between two different and distinct states.
Given that most systems we know of are open and constantly exchanging energy of matter and, perhaps most importantly, exchanging information with their environment, Prigogine observed that all such systems should be viewed as fluctuations.
At times such fluctuations may become so powerful that a pre-existing level of organization in a system cannot withstand the fluctuation. Prigogine called this moment of crisis for a system a "bifurcation point" and believes that when such a point is reached, a system has two options.
Either it will be destroyed by the fluctuation and disintegrate into chaos, or it will suddenly leap to an entirely new level of organization, a new internal order that Prigogine called a "dissipative structure" (because it dissipates the influx of energy, matter and/or information responsible for the disabling fluctuation).
It was for this theory of such dissipative structures that Prigogine won the 1977 Nobel Prize.
In short, in self-organizing phenomena such as the Zhabotisnky Reaction we have evidence of an entirely new property of matter. Not only can people and protozoa join hands to take part in the dance, but molecules can also. (End of book quotes.)
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