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swissy_fit

Sacrosanct Laws Of Thermodynamics Not Quite So Sacrosanct....

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What are the implications of this? It mentions that there are implications for various fields of research but doesn't say what they are....

And (excuse my ignorance) what about the energy in the laser light used to trap the particle?

http://www.gizmag.com/nanoparticles-violate-law-thermodynamics/31491/

Nanoparticles found to violate second law of thermodynamics

By Heidi Hoopes

April 3, 2014

It may be a little late for April Fool’s, but some skepticism is nonetheless warranted when reading that researchers have shown nanoparticles to disobey a fundamental law of physics which dictates the flow of entropy and heat in, it was believed, any situation. Specifically, researchers from three universities theoretically proposed then demonstrated that a nanoparticle in a state of thermal non-equilibrium does not always behave as larger particles might under the same conditions, with implications for various fields of research.

The second law of thermodynamics is the one that makes perpetual motion machines impossible. It states that the entropy – the measure for the disorder of a system – of any isolated system cannot decrease spontaneously, with the system evolving towards the state of maximum entropy (favoring disorder). The team has shown that a nanoparticle trapped with laser light temporarily violates this law. This seeming violation of universal law is transient, something that the researchers first derived as a mathematical model of fluctuations expected at the nanoscale.

To test their theorem, scientists at the University of Vienna, the Institute of Photonic Sciences in Barcelona and the Swiss Federal Institute of Technology in Zürich trapped a nanosized silica sphere with a radius of less than 75 nm in a laser "trap." Not only was the particle held in place, but could be precisely measured in three different directions, important when your particle is so small that 10,000 of them could line the width of a pinhead.

The nano-sphere was cooled lower than the temperature of the surrounding gas, creating a state of nonequilibrium. At a macro scale, a state of thermal non-equilibrium is what dictates that a snowman melts in a suddenly warming environment by absorbing heat from its surroundings, rather than growing more frozen by losing heat. A blindingly obvious example, yet at the nanoscale, such real-life observations are not without exception.

Indeed, by measuring the oscillations in the particle, the researchers were able to determine that the nanoparticle would, at times, effectively release heat to its warming surroundings rather than absorb heat.

Nanoparticles could range from natural parts within cells to man-made devices being developed in medicine and electronics. All of these particles experience random conditions due to their tiny scale. Both this experimental setup and the fluctuation theorem represent new ways to assess how nanoscale technology might fare when exposed to random environmental buffetings. Further studies are planned to further explore this phenomenon.

The research was originally published in Nature Nanotechnology.

Source: University of Vienna

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What are the implications of this? It mentions that there are implications for various fields of research but doesn't say what they are....

And (excuse my ignorance) what about the energy in the laser light used to trap the particle?

http://www.gizmag.com/nanoparticles-violate-law-thermodynamics/31491/

Nanoparticles found to violate second law of thermodynamics

By Heidi Hoopes

April 3, 2014

It may be a little late for April Fool’s, but some skepticism is nonetheless warranted when reading that researchers have shown nanoparticles to disobey a fundamental law of physics which dictates the flow of entropy and heat in, it was believed, any situation. Specifically, researchers from three universities theoretically proposed then demonstrated that a nanoparticle in a state of thermal non-equilibrium does not always behave as larger particles might under the same conditions, with implications for various fields of research.

The second law of thermodynamics is the one that makes perpetual motion machines impossible. It states that the entropy – the measure for the disorder of a system – of any isolated system cannot decrease spontaneously, with the system evolving towards the state of maximum entropy (favoring disorder). The team has shown that a nanoparticle trapped with laser light temporarily violates this law. This seeming violation of universal law is transient, something that the researchers first derived as a mathematical model of fluctuations expected at the nanoscale.

To test their theorem, scientists at the University of Vienna, the Institute of Photonic Sciences in Barcelona and the Swiss Federal Institute of Technology in Zürich trapped a nanosized silica sphere with a radius of less than 75 nm in a laser "trap." Not only was the particle held in place, but could be precisely measured in three different directions, important when your particle is so small that 10,000 of them could line the width of a pinhead.

The nano-sphere was cooled lower than the temperature of the surrounding gas, creating a state of nonequilibrium. At a macro scale, a state of thermal non-equilibrium is what dictates that a snowman melts in a suddenly warming environment by absorbing heat from its surroundings, rather than growing more frozen by losing heat. A blindingly obvious example, yet at the nanoscale, such real-life observations are not without exception.

Indeed, by measuring the oscillations in the particle, the researchers were able to determine that the nanoparticle would, at times, effectively release heat to its warming surroundings rather than absorb heat.

Nanoparticles could range from natural parts within cells to man-made devices being developed in medicine and electronics. All of these particles experience random conditions due to their tiny scale. Both this experimental setup and the fluctuation theorem represent new ways to assess how nanoscale technology might fare when exposed to random environmental buffetings. Further studies are planned to further explore this phenomenon.

The research was originally published in Nature Nanotechnology.

Source: University of Vienna

When you look at quantum systems stuff gets weird. Here's an example of weirdness in a system I use where QM conspires to produce a result that is somewhat at odds with basic classical thermodynamics.

http://en.wikipedia.org/wiki/Negative_temperature

This system may well be exhibiting the same effect (I haven't checked in detail). It's no big deal.

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If you make your snowmen really small, you may be able to use them to heat your shed.

I like the way you thought about snowmen instead of demons. It shows that you're a happy person.

wiki Maxwell's Demon

In the philosophy of thermal and statistical physics, Maxwell's demon is a thought experiment created by the physicist James Clerk Maxwell to "show that the Second Law of Thermodynamics has only a statistical certainty".[1] It demonstrates Maxwell's point by hypothetically describing how to violate the Second Law: a container of gas molecules at equilibrium is divided into two parts by an insulated wall, with a door that can be opened and closed by what came to be called "Maxwell's demon". The demon opens the door to allow only the faster than average molecules to flow through to a favored side of the chamber, and only the slower than average molecules to the other side, causing the favored side to gradually heat up while the other side cools down, thus decreasing entropy.

which strikes me as classical physics equivalent of medieval theologians supposedly debating how many angels can dance on a pin*

(* ans =

8.6766×10^49)

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The 2nd law of thermodynamics is only a statistical law. On average, a hot object will lose energy to colder surroundings. It may, however, do it in a rather haphazard way, if it is sufficiently small, that statistical noise becomes relevant (i.e. the processes of energy transfer don't get smoothed out because there are so few of them).

A casino makes money year after year, and gamblers lose money year on year. However, an individual gambler may temporarily gain money.

My reading of this article (the original paper seems to be "DDoS"ed and paywalled) suggests that in a sufficiently small system, this statistical fluctuation shows up. In the long term, energy always gets lost - but there may be short term gains.

This is not a new idea, experiments demonstrating this have been performed over 10 years ago My link. The theory behind it is also not new. Maxwell wrote about the statistical nature of the 2nd law in 1878.

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The 2nd law of thermodynamics is only a statistical law. On average, a hot object will lose energy to colder surroundings. It may, however, do it in a rather haphazard way, if it is sufficiently small, that statistical noise becomes relevant (i.e. the processes of energy transfer don't get smoothed out because there are so few of them).

A casino makes money year after year, and gamblers lose money year on year. However, an individual gambler may temporarily gain money.

My reading of this article (the original paper seems to be "DDoS"ed and paywalled) suggests that in a sufficiently small system, this statistical fluctuation shows up. In the long term, energy always gets lost - but there may be short term gains.

This is not a new idea, experiments demonstrating this have been performed over 10 years ago My link. The theory behind it is also not new. Maxwell wrote about the statistical nature of the 2nd law in 1878.

life is a short-term gain.

... or perhaps the universe represents a short-term loss.

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