New evidence for quantum Darwinism found in quantum dots

May 10, 2010 By Lisa Zyga feature
These images show a recurring scar found in simulations that bears a strong resemblance to experimental images. Scars were found to replicate and produce offspring states in agreement with quantum Darwinism. Image credit: A.M. Burke, et al. ©2010 APS.

(PhysOrg.com) -- Physicists have found new evidence that supports the theory of quantum Darwinism, the idea that the transition from the quantum to the classical world occurs due to a quantum form of natural selection. By explaining how the classical world emerges from the quantum world, quantum Darwinism could shed light on one of the most challenging questions in physics of the past century.

The basis of almost any theoretical quantum-to-classical transition lies in the concept of decoherence. In the , many possible quantum states “collapse” into a single state due to interactions with the environment. To quantum Darwinists, decoherence is a selection process, and the final, stable state is called a “pointer state.” Although pointer states are quantum states, they are “fit enough” to be transmitted through the environment without collapsing and can then make copies of themselves that can be observed on the . Although everything in our world is quantum at its core, our classical view of the universe is ultimately determined by these pointer states.

Since quantum Darwinism was first proposed in 2003 by Wojciech Zurek of Los Alamos National Laboratory, several studies have found evidence to support the idea. Most recently, a team of physicists and engineers from Arizona State University and the Naval Research Laboratory in Washington, D.C., has performed experiments using scanning gate microscopy to image scar structures in an open quantum dot. Their results have revealed the existence of periodic scar offspring states that evolve and eventually contribute to a robust state, much in the way that the derivation of pointer states is predicted by quantum Darwinism.

The “scars,” as the researchers explained, are actually scarring on the quantum wave functions, which cause the wave functions’ amplitudes to be highly concentrated along classical trajectories. Scars are traditionally thought to be unstable, where any small perturbation could break up the connection to the classical trajectory. However, when scar states replicate and evolve through quantum Darwinism, becoming a family of mother-daughter states, they can become coherent and eventually stabilize into multiple pointer states.

To detect this scar replication, the researchers used scanning gate microscopy to scan a conductive tip over the scar structures at a constant height. The tip acts as a local perturbation by causing a change in electrical conductance proportional to the sample’s electron density at that location. By measuring the change in conductance at different locations, the technique revealed that the scar structures have a periodic magnetic field that fits well with the idea of periodic offspring states.

“The magnetic periodicity, which we used to get the experimental data results, is the ‘smoking gun’ for quantum Darwinism,” coauthor David Ferry of Arizona State University told PhysOrg.com.

The agreement of the experimentally derived patterns and simulation patterns during variations in conductance also supports the idea that these periodic patterns represent offspring states. As the scientists explain, when the magnetic field increases, these offspring modes “push through” an energy level called the Fermi level and emerge as pointer states, which are detectable.

The ability of pointer states to make copies of themselves and produce descendants, as shown in these observations, is a key requirement of quantum Darwinism. By demonstrating this pointer state evolution in the scar structures of an open quantum dot, the physicists’ discovery provides evidence for the theory of quantum Darwinism - and, in turn, why we live in a classical world that is free from quantum effects such as superposition and uncertainty. Still, as Ferry explained, more work is needed before the theory becomes widely accepted.

“It is a theory, and our data provides support,” he said. “But, the experiments have to be confirmed by other groups, perhaps many times if the theory is to be fully accepted.”

Explore further: Attack on classical cryptography system raises security questions

More information: A.M. Burke. “Periodic Scarred States in Open Quantum Dots as Evidence of Quantum Darwinism.” Physical Review Letters 104, 176801 (2010). Doi:10.1103/PhysRevLett.104.176801

4.6 /5 (51 votes)

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ZeroX
May 10, 2010
This comment has been removed by a moderator.
ZeroX
1.7 / 5 (11) May 10, 2010
The dispersion of objects by CMB noise works in the way, all smaller objects are dispersed by this noise into radiation, while all larger ones are condensed by their gravity. In my theory it's a consequence of geometry of nested random fluctuations of aether.

The more interesting question may be, why more animals are larger, then the CMB wavelength? The above model works not for creatures as such, but for their brain waves, which such creatures are hosting. The true observers of universe are just the clusters of solitons inside of our brains - our bodies are just envelopes, providing safety for these virtual organisms and it enables to survive longer.

When we consider this, then the geometric model of Universe works well. The another question is, are the CMB waves adopted to human brains, or vice-versa, or the wavelength of both waves converges together?
ZeroX
1.8 / 5 (10) May 10, 2010
There is another evolutionary consequence of this model - if the most optimal size of all organisms corresponds the wavelength of CMB noise, shouldn't the very first organism appear like relativelly large droplets? Current theories of life evolution consider various mechanisms at molecular level, but I presume, if first organisms would be as large, as the largest protozoa, then the explanation of spontaneous formation of life could be a much easiers, because it would enable to incorporate all existing forces, including gravity.

http://www.scienc...0531.htm

From these reasons I presume, the first organisms were formed by rather large droplets (liposome coacervates), which divided by mechanical forces, probably at the interface of all three phases of matter, i.e. at coastal surf or something simmilar. In this way, the most advanced organisms were always rather close the scale of CMB radiation, which is the distance scale of the highest complexity.
ZeroX
May 10, 2010
This comment has been removed by a moderator.
ZeroX
1.4 / 5 (9) May 10, 2010
The understanding, why just wavelength of CMB noise is significant with respect to final result of quantum Darwinism we should realize, this noise is forming natural boundary between world of relativity and quantum mechanics. By this article relativity ends, where weak equivalence principle ends - and this is just a quantum scale:

http://www.physor...148.html

But the scale of quantum phenomena is substantially larger, then many people belive, because weak ekvivalence principle is broken by many common forces, like the electrostatic force, Casimir force, dispersion etc at centimeter scale. The size of magnetic domains inside of ferromagnetics could exceed many milimeters in size. And the CMB noise is the most tangible source of quantum fluctuations, which introduces extradimensions and violates equivalence principle and Lorentz symmetry in vaccum at small scales. In dense aether theory just the CMB noise is the manifestation of superluminal gravitational waves, too.
nuge
4.6 / 5 (5) May 10, 2010
The two best ideas in history just mated.
Skeptic_Heretic
2.8 / 5 (5) May 10, 2010
I'm intrigued. If all of reality is governed by evolution of state and wave form then a true ToE could be subtly peeking at us from experimental observation at the LHC. This means we're even closer to reverse engineering reality than we recognize. And once we understand the fundamentals, technological manipulation isn't far off.
ZeroX
1.6 / 5 (7) May 10, 2010
And once we understand the fundamentals, technological manipulation isn't far off.
I presume, we could create living organisms (eubionts) just by shaking of proper oil dispersion of proteins for sufficiently long time. We should give individual droplets sufficient time to collect surfactants from their neighourhood and keep them growing to sufficient size. The droplets, which would be most sufficient in collecting of their "food" will prevail in mixture less or more later. Later such dropplets could learn to produce their own proteins and to fight/dissolve another dropplets for food, etc.

I don't know, how LHC experiments could help us in evolution of these thingies, though. IMO these experiments could reverse human evolution fast, instead. Quantum Darwinism is strictly reversible process (like every quantum phenomena) - and it doesn't care about complexity of its products.
ZeroX
2.1 / 5 (7) May 10, 2010
The two best ideas in history just mated.
These ideas could be derived by using of dense particle model in more straightforward, deeper and less ad-hoced way. The process of ideas formation is similar to boiling of fluid (which is a sort of quantum Darwinism too, btw) - tiny isolated bubbles of new ideas (a new phase interface) apears a well before the more consistent model emerges.

In dense aether model the evolution of foam of living matter is just a seamless continuation of evolution of foam of nonliving matter. And the evolution of various theories and memes inside of human society is just a continuation of the evolution of living matter, too. Conceptually all these processes are the same and they're product of brane collisions (the splash of aether density gradients, during which the more and more complex foam phases gradually emerge). The success of human evolution would depend on many cosmological factors, which we cannot affect at all
JayK
2.9 / 5 (8) May 10, 2010
quantum Darwinism? Really? Is it so cool to add "quantum" to anything else that you get something better 100% of the time? Darwinism actually isn't exchangeable for "survival of the fittest" and most biologists get pretty testy when they hear "Darwinism" since it used as an epithet by creationists. I wonder that the recent origins of the term "quantum darwinism" might not be a mistake by its founders.
ralph_wiggum
5 / 5 (4) May 10, 2010
These ideas could be derived by using of dense particle model in more straightforward, deeper and less ad-hoced way. The process of ideas formation is similar to boiling of fluid (which is a sort of quantum Darwinism too, btw) - tiny isolated bubbles of new ideas (a new phase interface) apears a well before the more consistent model emerges.

In dense aether model the evolution of foam of living matter is just a seamless continuation of evolution of foam of nonliving matter. And the evolution of various theories and memes inside of human society is just a continuation of the evolution of living matter, too. Conceptually all these processes are the same and they're product of brane collisions (the splash of aether density gradients, during which the more and more complex foam phases gradually emerge). The success of human evolution would depend on many cosmological factors, which we cannot affect at all


Yeah, well, you know, that's just, like, your opinion, man
Alizee
May 10, 2010
This comment has been removed by a moderator.
Alizee
May 10, 2010
This comment has been removed by a moderator.
Alizee
May 10, 2010
This comment has been removed by a moderator.
Alizee
May 10, 2010
This comment has been removed by a moderator.
croghan27
3.8 / 5 (4) May 10, 2010
quantum Darwinism? Really? Is it so cool to add "quantum" to anything else that you get something better 100% of the time? Darwinism actually isn't exchangeable for "survival of the fittest" and most biologists get pretty testy when they hear "Darwinism" since it used as an epithet by creationists. I wonder that the recent origins of the term "quantum darwinism" might not be a mistake by its founders.


JayK - now if they could just add, in there somewhere, the term (as a noun, adjective, adverb or possibly a verb) NANO - they could really have a winner ... movie rights assured.
ormondotvos
not rated yet May 10, 2010
Just keep posting. It's fascinating to follow... or think I follow. I too tripped on what the strict definers of evolution would say, but Dawkins would go for this, I think. Ask him.
Daniel_Ebbole
5 / 5 (2) May 10, 2010
It is fine to adapt 'Darwinism' as a term but do not try to mix biological meaning with non-biological phenomena. These scars may self assemble and be propagated but using biological terms isn't really useful because it doesn't make the concept more easy to visualize.
mosahlah
1 / 5 (1) May 11, 2010
I propose the entire existence of quantum phenomena is due to limitations of the matrix. Maybe its not THE matrix, but one created by some natural process.
ZeroX
May 11, 2010
This comment has been removed by a moderator.
fullbony
1.5 / 5 (6) May 11, 2010
another example of something trying to pass as science. darwinism itself is hardly a science due its open-ended nonpredictive explanations ( everything is the way it is because thats the only way it could be and will be in the future as it needs to be.) , now, we are supposed to apply this to the quantum level for added clarity !
in the context of physics, natural selection is simply a math problem : throw a zillion atoms together, shake and stir well for an indefinite amount of time and you will see human being assemble out of thin air ( with all the evolution in between ). the actual probably as computed by some physicist of this happening is longer than the lifetime of the universe as we understand it. go figure. you see, darwinism is not a theory, it is simply a belief.

ZeroX
2.9 / 5 (7) May 12, 2010
..darwinism itself is hardly a science due its open-ended nonpredictive explanations..
Evolutionary theory gives many testable predictions regarding both phenotypes, both genotypes. For example, if you're a descendant of apes, they you should have a similar genes, only these few latest ones will be changed - and this could be tested by analysis of both DNAs.

Of course, we cannot go back into history to make sure, evolution occured in the way, which corresponds the phylogenetical tree - but this falsifiability poses exactly the same problem, like at the case of creationism. But we can predict various consequences - for example in stratification of fossil layers (dinosaurs had less genes then apes, because they existed here before apes - so we will find them in deeper layers, then the ape fossils - which is testable easily). Etc.
ZeroX
1.7 / 5 (6) May 12, 2010
The evolution may not be distinguishable from creation in some cases. For example the construction of cars evolved rather spontaneously from simpler forms to more complex ones, which were tested for fitness at free market. Therefore from perspective of cars it many be not so easy to distinguish, whether their construction ocurred by creation or not. There you can read about Darwinian evolution of cooking recipes.

http://www.newsci...ion.html

Dense aether theory considers evolution as a sort of biological thermodynamics.

http://www.wired....n-as-bi/
_ilbud
5 / 5 (3) May 13, 2010
ZeroX has a penis 1.9 cm long and has gone mad trying to justify it.
Skeptic_Heretic
5 / 5 (4) May 13, 2010
Evolutionary theory gives many testable predictions regarding both phenotypes, both genotypes. For example, if you're a descendant of apes,

Great, another person completely ignorant of evolution theory. Humans are not decendants of apes, evolution has not stated that we are. Apes and us come from a common ancestor, who is no longer around. Please learn the basics of a topic before you attempt to speak on said topic.

the actual probably as computed by some physicist of this happening is longer than the lifetime of the universe as we understand it. go figure. you see, darwinism is not a theory, it is simply a belief.

Then it's a good thing that Evolution isn't random, like your suggested experiment above.

If I punch you in the face, it hurts.

If the environment changes and "punches a species in the face", particular characteristics hurt the animal that has them.
vidyunmaya
May 13, 2010
This comment has been removed by a moderator.
thales
5 / 5 (1) May 15, 2010
So I'm thinking if quantum structures can show evidence of having evolved, could the large-scale structure of the universe show something similar? You know, like a giant periodic scar. I'm already favorable to the idea of branching multiverses, so let's get some evidence for it I say.
magpies
5 / 5 (2) May 15, 2010
Ya I agree 100% quantum should be infront of anything you say to make it at least 50% better.

Quantum Awsomeness Quantum Brothers.
Alizee
May 16, 2010
This comment has been removed by a moderator.
xponen
not rated yet May 18, 2010
This ancestor was ape by all criteria, too. The ancestors of apes are dated to more than 24 million years ago, whereas ancestor of people are only 7 million years old only, when apes were already evolved and serving well....

I disagree. -Ape, Neanderthal, Cro-magnon (Humans) is 3 distinct species which evolved from a common-ancestor.
ZeroX
1 / 5 (1) May 18, 2010
I disagree. -Ape, Neanderthal, Cro-magnon (Humans) is 3 distinct species which evolved from a common-ancestor.
Yep... and this common ancestor was still an ape (superfamily Hominoidea in particular, not to be confused with family Hominidae). Read the taxonomy.
Skeptic_Heretic
3 / 5 (2) May 18, 2010
I disagree. -Ape, Neanderthal, Cro-magnon (Humans) is 3 distinct species which evolved from a common-ancestor.
Yep... and this common ancestor was still an ape (superfamily Hominoidea in particular, not to be confused with family Hominidae). Read the taxonomy.
Taxonomy is out of date and wholly inaccurate in most cases. The precursor to humans and apes was the first primate. As far as we're aware the first divergence was between great apes and human/chimps, then you have further divergence in the ape line bringing about what we see in nature while human/chimp diverged into two groups, then chimps further diversified into chimps and bonobos.

This is our current understanding and yes, I've truncated the different homonidae that either cannot be jsutified as a human precursor, or who we cannot assimilate into either line. And yes, this is a very simplistic overview.
Carl_Vilbrandt
5 / 5 (1) May 29, 2010

I'm intrigued. If all of reality is governed by evolution of state and wave form then a true ToE could be subtly peeking at us from experimental observation at the LHC. This means we're even closer to reverse engineering reality than we recognize. And once we understand the fundamentals, technological manipulation isn't far off.


The subject restated:
Space time (reality) emerges from the evolution in the state matter driven by wave forms of quantum and/to relativistic scales then manipulation of the state matter would be the creation of 3D scaffoldings, that interact with the state of matter, quantum and relativistic waves modifying or expanding the current domain of reality.
Skeptic_Heretic
not rated yet May 29, 2010
Space time (reality) emerges from the evolution in the state matter driven by wave forms of quantum and/to relativistic scales then manipulation of the state matter would be the creation of 3D scaffoldings, that interact with the state of matter, quantum and relativistic waves modifying or expanding the current domain of reality.
Precisely. That is exactly the potential rammification of this type of understanding. "Virtual" reality control.
Jigga
not rated yet Jul 02, 2010
Quantum Darwinism is one of many postmodern theories or rather ideas based on correspondence principle ("everything is somehow connected with everything"), which tend more "explain", then predict.

http://en.wikiped...arwinism

Main problem is, Darwinian theory has very wide parameter space, so that it's virtually impossible to formalize it for obtaining of some testable predictions. And theories are defined only by their postulate sets.

We can see natural evolution in nearly everything, for example in condensation and coalescence of rain droplets during their fall - but actually, what can we predict/compute from such "model"? Such perspective is good mainly for writers of esoteric books about quantum mechanics, who need to extend their manuscript by few easy pages, which contradict to anything from the previous content.

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