Entangled States

The most beautiful equation ever

It is said that one day, when the great German mathematician Leonhard Euler was at the Court of Catherine the Great, a friend asked him for a proof of the existence of God. Euler is supposed to have replied with what is now called the Euler Identity and then essentially said Q.E.D.

Adam Frank explains the Identity and detail and points out just why it's both profoundly surprising, and to a numbers and relationship sort of person, beautiful, in a post over on the NPR Cosmos and Culture blog:

"The best equation ever - the incomparable and glorious Euler's Identity.  Here is it:

e^i(π)+1 = 0

 
Why are so many mathematically inclined folks sent into paroxysms of delight over this string of symbols which seem like gibberish to others.  Let me quote from Paul Nahin's wonderful Dr. Euler's Fabulous Formula: Cures Many Mathematical Ills -

I think [Euler's Identity] is beautiful because it is true even in the face of enormous constraint.  The equability is precise: the left hand is not 'almost' or 'pretty near' or 'just about' zero, but exactly zero.  That five numbers each with vastly different origins, and each with roles in mathematics that can not be exaggerated, should be connected by such a simple relationship, is just stunning.  It is beautiful.  And unlike the physics or chemistry or engineering of today which will surely appear archaic to technicians of the future, Euler's equation will still appear, to the arbitrarily advanced mathematicians ten thousand years hence, to be beautiful and stunning and untarnished by time.

So to begin with, its the appearance of those five magic numbers that starts things off.  Lets go down the list.

• Zero (0) which can be added to any number and the number is unchanged
• One (1) which can be multiplied to any number and the number is unchanged
• Pi which appears everywhere from trigonometry on to the most abstract domains of mathematics
• e which is the base of natural logarithms.  It is also a number which 'just shows up' again and again in the exploration of mathematics
• i which is the fundamental imaginary number.  There is no number which when multiplied by itself gives a negative result i.e. 1*1 = 1; (-1)*(-1)=1.  So someone just invented a new number: i = Square Root(-1).  They called it imaginary (cause it is) and so much mathematical magic suddenly appeared as to almost defy imagination.  How can an imaginary number be so central to mathematics?"

Read the full article here.

Seems like a profitable reflection for Labor Day.

String Theory makes a prediction. Scientists shocked.

The bigggest rap against String Theory till now has been that while it successfully can explain lots of interesting things, it doesn't actually predict anything. And if it doesn't predict anything, then according to Popper's ideas of Science, it isn't actually scientific.

But today comes surprising news that a group of theorists have managed to massage a prediction out of the spaghetti mathematics that is String Theory. And the prediction actually has something to say about the phenomenon of quantum entanglement. Specifically, it makes predictions about the behavior of 4 qubit entangled systems:

"'If experiments prove that our predictions about quantum entanglement are correct, this will demonstrate that string theory 'works' to predict the behavior of entangled quantum systems,' said Professor Mike Duff, lead author of the study.

[...]Duff and his colleagues realized that the mathematical description of the pattern of entanglement between three qubits resembles the mathematical description, in string theory, of a particular class of black holes. Thus, by combining their knowledge of two of the strangest phenomena in the universe, black holes and quantum entanglement, they realized they could use string theory to produce a prediction that could be tested. Using the string theory mathematics that describes black holes, they predicted the pattern of entanglement that will occur when four qubits are entangled with one another. (The answer to this problem has not been calculated before.) Although it is technically difficult to do, the pattern of entanglement between four entangled qubits could be measured in the laboratory and the accuracy of this prediction tested.

The discovery that string theory seems to make predictions about quantum entanglement is completely unexpected, but because quantum entanglement can be measured in the lab, it does mean that there is way – finally – researchers can test predictions based on string theory"

Read the full article here.

Or drop the theory all together, if the tests indicate that String Theory is unable to make correct predictions regarding 4 qubit behavior.

Hate to give up the brane model of the multiverse though if this doesn't verify. I really like saying "The Brane Multiverse".

Fine Structure Constant ain't constant?

What an interesting week so far! First a suggestion that we need to relax the Copernican Principle. Then a scientific test for the existence of Free Will. Now experimental evidence that a fundamental constant of Physics changes with time and location in the Universe.

The Fine Structure Constant is a measure of the coupling strength of the Electo-Magnetic field. It's roughly equal to 1/137. It's been measured to less than one part in a billion. It's very well observered. It's been of interest to physicists for a long time because of its nearly integer form. That fact has been linked often to Dirac's Large Number Hypothesis.

So the news this morning that research into the fine structure constant at the cosmological scale is showing a spread of values is a big deal. Apparently a telescope in the northern hemisphere looking at one side of the Universe is seeing one value and another telescope looking in another direction is seeing a different value.

"This means that in one direction, the fine structure constant was once smaller and in exactly the opposite direction, it was once bigger. And here we are in the middle, where the constant as it is (about 1/137.03599...)

That's a mind blowing result. One of the biggest conundrums that cosmologists face is explaining why the fundamental constants of nature seem fine tuned for life. If the fine structure constant were very different, stars and atoms wouldn't form and the universe as we know it couldn't exist. No theory explains why it takes the value it does which leaves scientists at a loss.

The implication from Webb and co's data is that the fine structure constant is continuously varying throughout space and is merely fine-tuned for life in this corner of the cosmos: the universe's habitable zone. Elsewhere, presumably well beyond the universe we can see, this constant is entirely different."

Read the full article here.

There's another implication. If the value is different in one direction than another, it mean's this is an experimental proof that the Copernican principle needs to be redone. Because, the fact that we happen to live in a region of space-time in which the fine structure constant is tuned to allow life to arise, then we can legitimately claim to be "special".

Ugh. It's fine to be special and all, but if physics doesn't work the same everywhere, it means there's going to have be some fundamental philosophical reevaluations made.

Where's Karl Popper when we need him?

Entanglement a measure of Free Will?

So do human beings have free will or not? That's not just a theological or philosophical question, it's also a scientific one. In a completely deterministic world as envisioned by Newton and his followers, every action is pre-determined by the conditions which lead to it. (Biology has a version of this question in its nature vs nurture debate.) Quantum effects, with their fundamental unpredictability are usually invoked to counter a deterministic world view, and create the space for free will actors in the Universe.

So here's something interesting today involving an idea that would seem to backdoor a way to explain away the results of Bell's Theorem which has confounded many for years. The issue is whether or not the randomness and unpredictability of the quantum regime is not actually fundamental. It arises because there's a deeper physics we don't understand. (This was Einstein's suggestion, and its line of reasoning is what led to Bell's work and the experimental verification of the non-locality of quantum effects.)

But Bell's analysis of the situation depends in a fundamental way on the observer in the system having free will. So what happens if the observer doesn't?

This is on the ArXiv blog today:

"Jonathan Barrett from the University of Bristol and Nicolas Gisin from the University of Geneva provide us with an interesting new take on this problem. They assume that entanglement does occur as quantum mechanics proscribes and then ask how much free will an experimenter must have to rule out the possibility of hidden interference.

The answer is curious. Barret and Gisin prove that if there is any information shared by the experimenters and the particles they are to measure, then entanglement can be explained by some kind of hidden process that is deterministic.

[...]In fact, if an experimenter lacks even a single bit of free will then quantum mechanics can be explained in terms of hidden variables. Conversely, if we accept the veracity of quantum mechanics, then we are able to place a bound on the nature of free will."

Read the full article here.

So, if this idea turns out to be broadly accepted, does this mean we can finally answer the conflict between supralapsarianism and infralapsarianism? Will we be Calvinist or Arminian as a result?

Radioactive decay rate influenced by the Sun?

Yesterday there was news that the Copernican Principle might need to be reexamined. Today there's news that radioactive decay rates aren't nearly as constant as we've thought. They appear to seasonally speed up and slow down - and increase when there's a solar flare.

That's sort of big deal because all of our time keeping is now based on the assumption that radioactive decay (at the macro level) occurs at a constant rate. It's an issue in medicine where anti-cancer drugs and treatments are administered assuming a constant rate, and if that's different during the year, then we're going to need to change things. I suppose radio-carbon dates might be adjusted too, but it might well be that the seasonal variations has the effect of canceling themselves out.

The effect was discovered, interestingly enough given my post yesterday about the Copernican Principle, by a researcher who was trying to verify another researcher's data regarding a sample array of radioactive decay rates. Observing the discrepancies, the scientists didn't just explain them away as mechanical problems, instead they looked closer and discovered, over a period of years, that the rates were seasonal.

"Going back to take another look at the decay data from the Brookhaven lab, the researchers found a recurring pattern of 33 days. It was a bit of a surprise, given that most solar observations show a pattern of about 28 days – the rotation rate of the surface of the sun.

The explanation? The core of the sun – where nuclear reactions produce neutrinos – apparently spins more slowly than the surface we see. 'It may seem counter-intuitive, but it looks as if the core rotates more slowly than the rest of the sun,' Sturrock said.

All of the evidence points toward a conclusion that the sun is 'communicating' with radioactive isotopes on Earth, said Fischbach.

But there's one rather large question left unanswered. No one knows how neutrinos could interact with radioactive materials to change their rate of decay."

Read the full article here.

How much fun is this? An excellent bit of scientific sleuthing. Even more fun because we don't understand why neutrino flux should change decay rates. More science to learn!

The end of the Copernican Principle?

One of the most important philosophical ideas in science, particularly in Astronomy and Cosmology, is the "Copernican Principle". In its shortest form it states "We are not special". The idea that human beings are not in a privileged reference frame was the underlying idea behind the Copernican revolution (in which science came to understand that the Earth is not the center of the Universe.)

Much of modern science depends on this idea, often in unspoken ways. We assume that physics works the same in all labs here on earth for instance when we expect scientific results to be reproducible and verifiable. If the Gravitational constant was different in China than it is in Brazil this wouldn't be the case. We assume that fusion works the same on the Earth as it does in Sun. And the same in the Sun as it does in Alpha Centari and as it does in giant blue and uv stars formed right after the big bang. We assume that galactic dynamics are the same in all galaxies...

Break this chain of reasoning and suddenly everything becomes questionable and our ability to explain phenomenon starts to fail. So it's never been really challenged since it was broadly accepted as a result of Kepler's and Galileo's use of Copernicus' ideas.

Except there's a problem. The application of the strict Copernican principle, which would say that physics works the same everywhere and at every era of cosmological history, is taking us to a place in Cosmology where we're inventing all sorts of complicated ideas to explain observations that seem to indicate the Universe is accelerating in its expansion, that it's primarily made of some sort of Dark Matter that we can't yet detect, and that Dark Energy automatically seems to violate a fundamental conservation law.

Seems sort of epicyclical in its complexity doesn't it?

Now apparently some cosmologists looking at this scandalous structure (and more than that) have asked the question "What if the Copernican Principle isn't as strict as we've insisted?"

They specifically decided to test the consequences of this idea by seeing what happens in one of the scandals of modern cosmology, the prediction of elemental abundances. Right now the standard models of the big bang predict that there should be about 3x as much lithium in the Universe as we observe.

" Marco Regis and Chris Clarkson from the University of Cape Town in South Africa say they can explain this shortfall in lithium. What's extraordinary, however, is that the same thinking also explains the supernova observations without any need for an accelerated expansion or dark energy.

Their new idea is that the lithium abundance can be explained by abandoning one of the fundamental assumptions of modern cosmology: the Copernican principle. This is the notion that humans have no privileged position in the universe. For cosmologists, this means that the universe must be more or less the same everywhere and on all scales.

Various cosmologists have pointed out that if we abandoned this principle, it would be straightforward to explain the supernova data. It simply means that the universe is not homogeneous on the very largest scale. Instead, we must be sitting at the centre of some kind of giant void in a much larger universe."

Read the full article here.

This is a rather breath taking idea for scientists. To some extent Relativity, which states as one of its fundamental assumptions that there can be no privileged or special reference frame is a systematic codification of the Copernican Principle. Relativity theory works pretty darn well and it's been repeatedly verified, but not necessarily at the Cosmic scale.

There are interesting philosophical problems associated with this idea too I imagine. I wonder what Karl Popper would make of it.

Any rate, this is a particularly interesting idea. It's much more elegant than having to modify newtonian gravity and other methods that have been suggested for fixing the scandalous observations of experimental cosmology. Elegance is often a sign that something is worth following up on in scientific circles. I expect we'll be hearing more about this...

How fast is the Beacon of Gondor? : Dot Physics

It's been a long summer already. How long? Physics professors, waiting around for classes to start, have enough time on their hands to answer important (to me) for questions about events in the Lord of the Rings.

In the film there's a beautiful cinematic sequence that shows the signal beacons being lit in Gondor and then the signal fires being lit along the tops of the mountains until the alarm is raised in Rohan:

Video here.

So, a professor in Louisianna asks the same question I did when I saw it: "How long does it actually take to alert the Rhoridiim?"

Rhett Allain writes:

"Can I get an estimate of these three parameters from that movie clip? Oh, yes I can. Will it be realistic? Who knows. Here is the stuff I found.

• When Pippin lights the first signal, it takes about 12 seconds from the time he puts the fire on it until it is mostly lit.
• After the first signal is on fire, Gandalf sees the next signal only 6 seconds later. WHAT?
• The guys (or gals) at the next station must have just been sitting there staring and waiting for a signal. Oh, it was probably like 40 years since the last time it was used. I guess you can do stuff like that if you don't have youtube. But wait, the more I think about this, the more upset I get. I am ok with invisible rings, flying dragons, glowing swords and stuff. However, it is beyond the bounds of reason to expect me to believe that some guys are sitting way on the other mountain with a hair-triggered lighting mechanism. Six seconds. Seriously.
• The next time to light is 12 seconds. That is reaction plus light time.
• The next one is at night and has a total time of about 6 seconds. At night! Don't these guys even sleep?
• 3 seconds for the next one. Come on man.

In this last one, Aragon notices the signal in under 2 seconds. Luck or skill?"

Read the full article here to see what he gets for an answer.

Spoiler: The film sequence isn't too over the top fanciful at all.

Thanks to David Simmons for the heads up about the post.

From organic entanglement to synthetic solar cells

There have been a number of papers recently which have suggested that amazing efficiency of the photosynthesis stems from its exploitation of quantum entanglement in the conversion from light to energy. Now some investigations into the details of the mechanism are beginning to give us a hint about how to move forward exploiting that knowledge to be build much more efficient solar cells:

"In a paper in The Journal of Chemical Physics, which is published by the American Institute of Physics, these ideas are put to the test in a novel computer simulation of energy transport in a photosynthetic reaction center. Using the simulation, professor Shaul Mukamel and senior research associate Darius Abramavicius at the University of California, Irvine show that long-lived quantum coherence is an 'essential ingredient for quantum information storage and manipulation,' according to Mukamel. It is possible between chromophores even at room temperature, he says, and it 'can strongly affect the light-harvesting efficiency.'

If the existence of such effects can be substantiated experimentally, he says, this understanding of quantum energy transfer and charge separation pathways may help the design of solar cells that take their inspiration from nature."

Read the full article here.

Imagine a solar energy farm that would comprised of leaves, small mechanical ones, instead of large southern facing panels. Certainly the HOA's of the world would be much happier. But more importantly, this may represent the big break-through we've all been waiting for in solar energy that will make it much more financially viable as a local energy source.

This is of no small interest in a place like Arizona where the sunshine in the desert state, if harnessed, could really turn us into the OPEC of solar power in the US. (Assuming we can upgrade the nation's electric grid into the hoped for smarter next generation one that is in development.)

Entanglement and DNA

I apologize for the extended silence on this blog. My family and I have been traveling; looking at colleges for our daughter who's a rising High School senior. I was back in the eastern US for much of the past month, living out of a suitcase and learning more about liberal arts colleges than I've ever known. It was all worth it. Even if our daughter doesn't attend one of the schools we visited, getting a chance to just hang out with her for one last long trip before she starts the process of leaving home and going off on her own was priceless. Plus we had some wonderful conversations and experiences that I'll treasure the rest of my life. (And which make the sticker shock of this whole thing more palatable...)

I've not been neglecting to keep up with my reading though. I've got pile 'o links to articles that were published over the past couple of months and I expect it's going to take me the rest of the summer to work through the backlog. I've been traveling with my new iPad, a truly wondrous device if you're traveling by air, and it makes staying current really quite easy. So sit back and enjoy the stream 'o news for the next few weeks or so.

A number of the articles that I've been reading and marked for posting have to do with the location of the effective boundary between classical and quantum mechanical behavior. Classical physics is fixedly deterministic. Mostly. Except when things go non-linear or chaotic. But mostly deterministic. Quantum physics just isn't. It's probabilistic. Most of the time this isn't a problem because the probabilism occurs at a regime far distant than the one which we experience.

But every so often an important part of our world turns out to depend totally on a quantum effect. Like solid-state transistors. Without the possibility of quantum tunneling, all the keen electronics we play with today wouldn't be possible. The computer I'm writing this upon, and the one you're using to read these words? Totally dependent on quantum physics. In a perfectly deterministic Universe, where "yes" was always "yes" and "no" was always "no", and where we could just use plain sense reasoning to work out what was going on around us, computers such as we use right now couldn't exist.

Neither too could we apparently.

Ever wonder what makes DNA able to create such magical, replicable, sequences of information? Scientists have. Simple chemical bonds don't have the reliability apparently - and will break down too easily for the DNA coding to be able to last very long.

So, now:

"a group of physicists say that the weird laws of quantum mechanics may be more important for life than biologists could ever have imagined. Their new idea is that DNA is held together by quantum entanglement.

That's worth picking apart in more detail. Entanglement is the weird quantum process in which a single wavefunction describes two separate objects. When this happens, these objects effectively share the same existence, no matter how far apart they might be.

[...]The question of course is how to prove this. They say that one line of evidence is that a purely classical analysis of the energy required to hold DNA together does not add up. However, their quantum model plugs the gap. That's interesting but they'll need to come up with something experimentally convincing to persuade biologists of these ideas.

[...]Speculative but potentially explosive work."

So, it's apparently theoretically tenable, solves a significant problem in biology, and nw needs to verified. It's not terribly surprising to me. Quantum entanglement apparently allows birds to literally see magnetic field lines and thus perform their amazing navigational feats. Perhaps biology is much more quantum than we've ever imagined.

Full article here.

So, if the probabilistic world is critically important to life, shouldn't we be thinking about how to talk about God using the same sorts of thinking? I mean, God makes life possible...

Stay tuned.

Protons a bit smaller than thought. Scientists world over gasp aloud.

An article in Nature (a very prestigious refereed journal) announced on Wednesday that a team of researchers have measured the radius of a proton and found it to be 4% smaller than expected.

Now, for me speaking from an astronomical view point, this is a pretty great result. In Astronomy we're often happy to get a measurement within a factor of 10 or so of what is predicted. But in elementary particle physics this small miss is a pretty big deal.

It could likely spell trouble for the Standard Model - which is the very successful description of interactions of the quarks and gluons that make up the internals of a proton. It's such big trouble that the first instinct of many, including the editorial board of Nature, that the researchers messed up their calculation somehow.

But, as an article in the LA Times says:

"If the startling results are confirmed, a possibility that at least some physicists think is unlikely because the calculations involved are so difficult, they could have major ramifications for the so-called standard model on which most modern physics is based.

In an editorial accompanying the report in the journal Nature, physicist Jeff Flowers of the National Physical Laboratory in Teddington, England, said there were three possibilities: Either the experimenters have made a mistake, the calculations used in determining the size of the proton are wrong or, potentially most exciting and disturbing, the standard model has some kind of problem.

If the theory turns out to be wrong, 'it would be quite revolutionary. It would mean that we know a lot less than we thought we knew,' said physicist Peter J. Mohr of the National Institute of Standards and Technology in Gaithersburg, Md., who was not involved in the research. 'If it is a fundamental problem, we don't know what the consequences are yet.'"

Read the full article here.

More here.

Neat! Stay tuned... (as Steve Jobs is wont to say of late.)

Literal human entanglement

I've been posting a number of stories this past week or so on advances made in exploiting the quantum entanglement phenomenon so that it has a macroscopic effect. But there's a paper this week which is arguing that we can actually use entangled photons to entangle human beings.

The idea is pretty straightforward. The human eye is sensitive enough to be able to detect a single photon. So, in a dark enough room, if you send out a pair of entangled photons and both are seen by human beings. Effectively you have "entangled" the wave functions of the human detectors as a result...

"But there's a problem: the number of photons needed to trigger detection, which is about 7 in humans. How do you reliably entangle at least this number of photons and still carry out the necessary tests?

Today, Sekasti and co lay out the various methods for transferring or cloning the entanglement from one of a pair of entangled photons to an ensemble of at least 7 photons, which would be large enough for a human to see. In such an experiment, a human eye would detect this handful of photons while a conventional single photon detector spots the other photon.

The question is whether the entanglement between the original pair of photons is preserved in this new ensemble in a way that allows a measurement that can only be explained in terms of a superluminal influence.

Their conclusion is that such a measurement is still possible but within certain limits. Sekatski and co say that the data only allows conclusions to be drawn about the initial 2-photon pair. But the bottom line is that it is definitely possible for a real person to see quantum correlations with the naked eye."

Read the full article here.

Heh. Not much use, but it's a neat idea. And it pushes the expected boundary between macroscopic and microscopic physics further into the human realm than most other experiments have imagined doing.

LEDs that create entangled pairs!

Well! This is just cool on so many levels. A team of optical-engineering types have found a way to create a specialized LED (light emitting diode) that will create a stream of entangled state photons on demand.

From the report on the Discovery Blog:

"Entangled photons have previously been made using a crystal to split laser light into photon pairs. The trouble with such ‘parametric down conversion’ is its unpredictable nature. ‘Sometimes you get two pairs of photons, sometimes one, sometimes zero,’ says Stephenson [sic]. ‘That’s not exactly reliable if you want an error-free quantum computer’ [New Scientist].

The team’s device, which produces these particles just in pairs, is a indium arsenide quantum dot connected to a little LED. (A quantum dot is semiconductor that measures only nanometers in size—small enough that weird quantum behaviors arise.)

When the researchers supply the LED with electric current, two electrons hop into two positively charged ‘holes’ in the quantum dot’s lattice, releasing energy in the form of a photon pair. Crucially, the nature of this process means that the polarization of one generated photon is determined by the other, so the pair is entangled [Nature]."

Read the full article here.

It's a small output device right now, and it's not commercially available, but when it is, it means that one of the key promises of quantum computing - impossible to intercept communications - will be much closer to reality.

And it's just fascinating to me that this will represent another macroscopic use-case of a quantum phenomenon. (Transistors are another.) The basic premises of classical and relativistic physics say this is impossible. And yet they not only exist, in the case of solid-state transistors, they make it possible for you to read these words right now.

In physics we always expect that if you want to find new science, you have to start by re-examining the basic premises of the old science. Topple an axiom and you're likely to get yourself to something interesting very quickly. (Like what Riemann did in geometry when he wondered what would happen in a space in which parallel lines actually did eventually meet...)

Entanglement, with the support of the Bell Thm that this is fundamental to nature, seems to me to be another one of the axiom toppling mechanisms.

Can the Ansible be far behind?

Last week there was a report that scientists in China have managed to keep particle states entangled out to a distance of 10 miles. That means that changes to an entangled particle in the lab should be instantly transmitted to the particle 10 miles away. But this doesn't mean that we can now send a signal faster than the speed of light. At least not yet...

The problem in entanglement is that while the particles change state instantly, any attempt to observe the state destroys the entanglement. Which then means that while the information travels faster than the speed of light, the observation of the information is lightspeed limited, because the lab has to signal to the external observer that the state has changed so that the correlation can be measured.

But there's a paper today that reports that there is hope that not all quantum properties are destroyed when observed. In particular researchers in Finland are publishing a paper this week that shows that a certain class of quantum correlations propagate out to classical length scales. The claim that these represent the transitional cases between quantum decoherence and macroscopic classical behavior:

"This particular correlation can be found, for example, in quantum systems comprising of two qubits. ‘These qubits, each with different properties, such as different polarizations, have to interact with a type of noise that doesn’t change the energy of the qubits,’ Maniscalco explains. ‘Instead of changing the energy, the noise just changes the phase, such as flipping polarizations. The type of noise that we have considered is one that contains all frequencies in a way that is very similar to white noise.’

While this discovery is theoretical, Maniscalco says that it has an experimental basis as well. ‘A very recent experiment has confirmed a type of quantum correlation that is not affected by the environment. And this is not a weird type of environment; it’s a natural environment that we could work in right now.’ (For more on this experiment, see Jin-Shi Xu, et. al., ‘Experimental investigation of classical and quantum correlations under decoherence,’ Nature Communications (April 2010). Doi:10.1038/ncomms1005.)

In the last 20 years, Maniscalco points out, technology has advanced to the point where it is possible to use single atoms or photons to build quantum logic gates for future quantum computers, or perform communication, measurement and cryptography tasks. ‘We’ve learned that it is possible to exploit the quantumness of the microscopic state, but in order for us to succeed, the quantum properties have to remain intact for a long time. That is a challenge, since once the properties are lost through interaction with the environment, a device can’t exploit quantumness.’

This discovery that certain quantum correlations are not lost in presence of the environment could lead an increased ability to exploit the quantum world for use in technological devices. Maniscalco points out that the idea that all quantum properties need not be lost through interaction with the environment presents more than interesting fundamental implications. ‘While this work has a surprising fundamental aspect,’ she says, ‘it opens up a whole range of possibilities with applications in quantum technology, including computing, communications, metrology and cryptography.’"

Read the full article here.

An ansible is a tool that allows for a faster than light communication. The term was coined by Ursula K. Le Guin but it's appeared in numerous novels since. It's a pretty obvious concept assuming that you actually measure an entangled quantum state without destroying the entanglement. Call the up-state a 1 and the down-state a 0. It's a relatively simple project then to use a field on one end of the entangled state to flip the states up and down, and then use fields on the other end to measure the result. Since the states are entangled, the signal travels instantly - faster than the speed of light. You have a superluminal modem. Which means that we can talk to people in orbit around Saturn in real time, with out any light-flight induced delay.

Sub-space radio, here we come!

The faith of scientists

I've fallen a little behind on my blogging this past Easter season, so I'm just now getting around to posting this piece based on a tip from Paul M. Back around Easter time the results of the third major study of American scientists and their religious beliefs was released. The results are not terribly surprising to me at least, though they might be to some outside the scientific and/or religious communities:

"It turns out that nearly 50 percent of scientists identify with a religious label, and nearly one in five is actively involved in a house of worship, attending services more than once a month. While many scientists are completely secular, my survey results show that top scientists are also sitting in the seats of our nation's churches, temples and mosques.

Unfortunately, because of the controversy and conflicts surrounding the evolution-creation debate, stem cell research and other topics related to science and faith, most religious scientists do not feel comfortable talking about their scientific lives within their faith communities. They think discussing science within their house of worship might offend fellow parishioners who are not scientists. So they do not bring it up. Instead, they practice what I call 'secret science.' And everyone in the community loses out.

The most dangerous result of this reticence is a lack of role models for youth who might want to go into science but fear science might lead them away from faith. According to a recent report from the National Center for Education Statistics, U.S. schoolchildren receive poorer science education than do students in most other industrialized nations. Other research shows that how students experience science in elementary and secondary school--as well as how well their science abilities evolve--helps predict not only whether they'll enter a career in science, but also whether they'll attend college and enter higher-status fields (like engineering). Better science skills and understanding often correlate with greater overall success and socioeconomic stability."

Read the full report here.

This study strikes me as being very accurate in its depiction of the reticence of scientists to talk openly of their faith in secular settings. And I suppose some of that does have to do with the typical primitive way that the creation/evolution debate is framed by the loudest voices. (Voices which strike me as really using their positions in the debate for political or monetary gain in other areas.)

But some of it has to do with the fact that many scientists are not theologically literate enough to feel comfortable talking about their faith, the reasons for it, or what they gain by it. And many theologians are reticent taking about science because they don't really feel like they understand it and they have experienced only the certainty of scientific claims of commonly accepted theories and not the much more common uncertainty of theories proposed at the cutting edges of research. The two effects taken together means that unless you have someone with formal training in both fields, like a John Polkinghorne or the Presiding Bishop, you don't have much opportunity for real discourse.

It's the lack of real discourse that I worry is contributing to the danger listed in the third quoted paragraph above. Young people really don't see many role models in their everyday life. Honestly, it was out of my desire to fill that lack as much as anything else that I agreed to take a position as an adjunct at Lehigh University for five or six years teaching Physics and Astronomy. When I was talking about the job with the chair of the department back in 2000 *my* big question was whether or not they would allow me to teach in my clericals. I argued that I didn't have time to change between the mornings in the parish and the afternoons in the lecture halls. But I was really sort of hoping that by appearing before a science classroom in a secular university dressed as a priest, I could give a sort of silent witness that faith and science don't have to necessarily be seen as being at odds with each other.

I don't know if I was as successful as I would have liked to have been, but over the years I did have a small number of students (10 or so?) show up in the parish either for a special teaching series or just to come to church on Sunday morning to see me in that context. I did end up baptizing two of my former students. And I think because I was sort of "exotic" in my dress, I was asked to be a faculty scholar for one of the nicer fraternity houses on campus - which afforded me the opportunity of extensive informal conversation with the brothers and their friends.

The one thing I can point to that did show me I was making a difference came at the end of one of the astronomy courses that I regularly taught. I had just collected the final evaluations from the students (and important tool in judging the quality of their educational experience) and was gathering up my things to leave the lecture hall. One of the students, someone who I can't recall ever raising his hand before, suddenly shot up his hand and called out "Professor? You're religious right?"

I allowed as how I was.

"You've been lying to us all semester then."

I was sort of taken aback. The class left in the room all seemed to inhale at the same time. "What do you mean?"

"You keep telling us the Universe is almost 15 billion years old. You keep telling us the solar system is something like 5 billion years old and the Earth is like 4.5 billion years old. But you're religious. So you don't believe that. You're lying to us."

"Ah", I thought. "He can't imagine any other way of being religious than being a young earth creationist because I suppose that's what he's seen in the movies..."

I responded, "Well, you know, there's more than one way to understand what the Scriptures teach about creation. I'm Episcopalian. We use the Bible differently than most of the people you seem to think of when you think of religious people."

The class sort of chuckled. I guess my answer satisfied them as well as the student who had asked the question. (By this point the Episcopal Church had moved from being a word they didn't know how to pronounce, to a denomination most of them were familiar with. I suppose that can be attributed to the consecration of Bishop Gene Robinson and the dustup that resulted in American christianity.)

That was the end of the encounter. No matter what the young people in the class thought about the actions of the Episcopal Church, they now knew a few new things that were unrelated to anything else I had been talking about during the semester. One, that not all Christians interpret the Bible in the same way. Two, it was possible to talk about religion without having someone rise to the bait or react defensively. And three, it was possible to believe that science and religion can live with one another.

That seems enough to me. At least let the seed get planted. Hopefully they'll work out the answers themselves. I find that the answers to important questions have more staying power in the long run that way anyhow. Both as a teacher and as a preacher.

I haven't taught again since I've come to Phoenix. I just don't have the time right now. But perhaps I be given the opportunity again. If I do, hopefully I can strike the same deal. I'll teach for not much money, but I do want to be allowed to present myself to the class as I really am. A Christian who believes in Jesus and an Episcopal priest who tries again and again to make decisions based on that faith.

And if not me, I hope that other people will. It would give me hope that there will be answer to the concern listed in the article above.

Can two opposing ideas be true at the same time? Science seems to say "yes" once again.

One of the most wonderful aspects of scientific thought in the 20th century was the realization that light had both a particle and a wave aspect. (So, it turns out, does everything.) There's no way logically that you can be a particle (localized) and a wave (which is found everywhere) at the same time. And yet, as Einstein theorized, and DeBroglie in his steps, that's exactly what the Universe does.

For a long time philosophers and scientists assumed that this inherent duality was an artifact caused by imperfect understanding. But the more we look at the situation, the more stubbornly the data indicates that it's not an approximation of reality. It is reality. We may not be able to completely conceive it. But it's what *is*.

There appears to be a new frontier that we're going to be working to get our heads around another dualistic paradox. For many years now physicists have been trying to understand whether the data about the expanding and accelerating edge of the Universe needed to be explained by modifying the classical understanding of Gravitation -"modified Newtonian dynamics" or MOND (which would include General Relativity too), or by positing an entirely new sort of matter that gravitates but does not emit photons (Dark Matter).

Both ideas have proponents, with the majority of people of late coming down on the "Dark Matter" side of the solution.

But a new team has suggested that maybe the answer isn't either/or but rather both/and once again. The same group of physicists who have been suggesting that perhaps Gravity is really an entropic phenomenon, being related to information flow in the Universe rather than a fundamental force, are now seeing that their idea can be extended.

An article on the ArXiv Physics blog explains how the model has been modified to be more accurate, and what the results where when that was done.

"So far, [the new model] has assumed a simple universe. But cosmologists know that our Universe is not only expanding but accelerating away from us. What Chui and co. have done is derive gravity as an emergent force using the same entropic approach but this time in a universe that is accelerating.

The result is a form of gravity in which parameters for acceleration and mass share a strange kind of duality: either the acceleration term can be thought of as modified as in MOND; or the mass term can be though of as modified, as in the dark matter theory.

In effect, Chui and co are saying that dark matter and MOND are two sides of the same coin.

Interestingly, the effect of each type of modification seems to be scale dependent. In this theory, the MONDian interpretation works at the galactic scale while the dark matter interpretation works best at the scale of galactic clusters."

From here.

That's really quite lovely. This approach has the benefit of explaining all sorts of seemingly unrelated phenomenon like why gravity resists quantization and now why we have two contradictory but equally successful paradigms.

Perhaps our human need to find clarity is just a human need. Perhaps the Universe doesn't have a single way of doing things, but instead conjoins paradox in a way that is wholly unsatisfactory to the enlightenment mind.

Actually, my gut feeling about this is that there's no maybe about it. Reality is paradoxical and does not lend itself to clarity at all. I think the reason for that has to do with our creature-ly-ness and our finitude as human beings.

I was thinking about this today when I read David Anderson's latest letter.

He is criticizing the Episcopal Church for its decision to ordain Mary Glasspool as a bishop in California and in the middle of his letter he writes:

The difficulty is that the two opposing viewpoints are based on non-compatible reference systems: one is based on human reasoning and feelings, the other on the revealed Word of God. One is right, the other is not, and you can't compromise and cut the baby in half, so that each belief system has half of what they wanted.

Leaving aside any response on the situation which gives birth to his statement, it's the idea that two opposing viewpoints can not coexist which bothers me.

Why not? Isn't that just what we do in the Episcopal Church's liturgical formulation of the Elizabethan compromise: "The Body of Christ, The Bread of Heaven"?

Since Anglicanism has no strong tradition that believes the biblical witness is literally word, for word from God, human beings must have had a non-trivial part to play in its writing and editing. And if that's the case, how do we tease out where the human emotions and reason leave off and the inspiration of God begins?

I'm not asking this to score rhetorical point against Bishop Anderson here, I'm writing because I think the idea that we can separate one strand from another in the creation of the Canon is likely an over-reach on our part. Like the particle and the wave, like MOND and Dark Matter, it's both/and AND either/or depending on the situation.

I've cautioned against binary thinking that arises from overly appreciating the enlightenment before. I suppose this is just another of those notes.

But perhaps someone will read this and hear my point anew this time.

Teleportation at distance of 10 miles

Some rather exciting news today. A team of scientists in China announced that they've been able to extend the distance that a photon's state was able to be instantly teleported to just about 10 miles (16km).

The idea behind quantum teleportation is that you take two entangled state objects (like a pair of electrons, or in this case a pair of photons) and then make use of the non-classical behavior of entanglement which means that changes to one object instantly modify the other. (Instantly is faster than the speed of light...) So this is really more about the creation of something like sub-space radio from Star Trek than it is the Teleporter that Mr. Scott used so artistically.

From the report on the methodology used:

"In previous experiments the photons were confined to fiber channels a few hundred meters long to ensure their state remained unchanged, but in the new experiments pairs of photons were entangled and then the higher-energy photon of the pair was sent through a free space channel 16 km long. The researchers, from the University of Science and Technology of China and Tsinghua University in Beijing, found that even at this distance the photon at the receiving end still responded to changes in state of the photon remaining behind. The average fidelity of the teleportation achieved was 89 percent.

The distance of 16 km is greater than the effective aerosphere thickness of 5-10 km, so the group's success could pave the way for experiments between a ground station and a satellite, or two ground stations with a satellite acting as a relay. This means quantum communication applications could be possible on a global scale in the near future.

The public free space channel was at ground level and spanned the 16 km distance between Badaling in Beijing (the teleportation site) and the receiver site at Huailai in Hebei province. Entangled photon pairs were generated at the teleportation site using a semiconductor, a blue laser beam, and a crystal of beta-barium borate (BBO). The pairs of photons were entangled in the spatial modes of photon 1 and polarization modes of photon 2. The research team designed two types of telescopes to serve as optical transmitting and receiving antennas."

Read the full article here.

This will have some interesting immediate application in quantum computing and, if the distance can be extended, information transmission.

Neat. Another macroscopic manifestation of Entanglement.

Is reality only real?

The question of the fundamental nature of reality is tackled today on the NPR Cosmos and Culture blog. A very long time ago Democritus suggested that reality is fundamentally made up of indivisible identical chunks which he called "atoms" (for un-cuttable). The atomic world view was a minority position in greek philosophy and relegated to a backwater in enlightment science for quite some time. It was only in the 18th and 19th century, as people began to recognize the scientific roots of alchemy, that atomism began to be studied seriously.

When I was a child, atomism had ceased to be about the elements and instead was taught to us in a philosophical sense in the statement that all matter was made up of protons, neutrons and electrons. That's not exactly true, and our teachers probably sort of knew that, but the idea that there was a relatively small number of fundamental entities in the Universe was commonly held. I suppose it's an echo of the physics idea that we should ultimately be able to reduce all of motion, etc. to a simple unified theory.

But these days, both of these ideas, that there's a small set of indivisible chunks of reality, and that we can reduce reality to a "simple" systematic mathematical model is looking less and less likely. Elementary particles are now thought to live in a spectrum of energy families (like the up and down quark, the electron and the electron neutrino or the charm and strange quarks, the muon and muon neutrino...). Physicists are starting to talk more and more about complexity theory and less about unified theories.

But there's still a philosophical question that needs to be answered. Is it even proper to talk about the experience of reality in terms of what is "real" or do we need to extend our search to include things like "potential" (or even "order/information")?

Stuart Kaufmann writes, in part:

"Monism is the view, shared by virtually all scientists, that the world is made of one kind of ‘stuff,’ the Actual world of matter and energy and with some question marks, space and time and information.

There are very good grounds to accept monism. And it has an ancient history. No less an ancient philosopher, Empedocles said, ‘What is real in the universe is what is actual.’

Aristotle was less sure, he toyed with the idea that both the Actual and the Possible were ‘Real.'  He called the Possible ‘potentia’ and meant a variety of things by Potentia. And no less a mathematician and philosopher than Alfred North Whitehead, he of Principia Mathematica in the early 20th Century, written with Bertrand Russell, moved on to think of both Actuals and Possibles as ‘real,’ or ‘ontologically real,’ meaning two kinds of ‘stuff’, Actuals and Possibles in the universe.

I’m beginning, to my surprise to think Aristotle and Whitehead may have been right. If so, the implications seem pretty radical.  I’m beginning to think of a dualism, Res Extensa and Res Potentia.  It cannot kill us to think about it, and it may be important."

Full article here.

Kaufmann goes on to trace the development of classical physics and the triumph of Newtonian reductionism as a paradigm as the underlying driver of the widespread adoption of the monistic worldview. But he points out that even early on, Newton was not without his challengers. Descartes, and to some extent the French physics school typified by LaGrange, talked about an alternative view based in part on potentiality, which we today think of as an energy treatment. It's that potentiality view that underlays the Schroedinger equation, the Heisenberg model and large chunks of quantum reality.

He writes on toward the end of his musings:

On this new dualism, Res Extensa and Res Potentia, what is then waving in the mathematical formalism of Quantum Mechanics is exactly what physicists say, but don’t mean, the waves are waves of “possibilities” (wink wink), and when you square the amplitudes of the waves you get probabilities, Born’s rule, and thank goodness Probabilities obey the law of the excluded middle. We are back on safe turf.

Maybe, just maybe, we have an ontological dualism. We have Res Extensa, the Actual. And we have Res Potentia, the Possible. Both are real as Aristotle hinted and Whitehead insisted.

If you think about it, our entire awake lives are guided by the Possibles we live with and act to create. (See my blogs: Toward a Responsible Free Will, and The Hard Problem Consciousness.) I begin to suspect that what I call the “Adjacent Possible” that grows forever out of the nexus of what is Actual, as in technological evolution, cultural evolution and history, is an ontologically real Possible.

Do read the whole thing. It's quite an interesting way of explaining the dilemma and it's easily accessible to the lay reader.

Quantum Darwinism and Ecclesiology: Gamaliel revisited

I've been a little quiet here lately, partly because I've been busy and partly because I've been thinking through some ideas about science and religion during Easter seaon. Hopefully as my ideas gel I'll find time to post them so that y'all can shoot at them and help me vet them. (I also have quite the backlog of articles that I've wanted to point to and I'm planning on getting them posted over the next couple of weeks.)

I saw news that an important new test of the idea of Quantum Darwinism was announced the middle of last week, and I've been thinking about that and the larger concepts all week since. Quantum Darwinism is a relatively recent attempt to make sense of how nature and phenomenon exist in both a quantum regime and a classical regime. Actually, more specifically, it's an attempt to explain how the observations of classical physics can arise from the non-intuitive world of quantum physics.

The idea in a nutshell is that quantum states that are suited to propagate at classical length scales are naturally selected over the states that are not. It's called Quantum Darwinism because this idea of natural selection obviously evokes the simple yet profound similar insight that Charles Darwin had when observing biological systems.

The idea was first proposed by Wojciech Zurek, a physicist at Los Alamos back in 2003. A simple summary can be found here.

How does it work? Zurek's way into this problem is to think about the role of the environment in quantum mechanics. For other quantum physicists, the environment has never been anything more than a nuisance. Consider a quantum object in isolation and the quantum information it contains can survive forever. But place it in the real world and this quantum information leaks into the environment, destroying the system under study.

Zurek takes different view. He thinks of the environment as an information channel and the properties of this channel are the key to understanding quantum darwinism.

All macroscopic measuring machines get their information through this channel. For example, at this very moment you are intercepting a fraction of the photons emitted by a screen. But we can never observe all of the environment, only a small fraction of it which reveal systems of interest.

This is the essence of quantum darwinism, says Zurek. Only quantum states that can be transmitted through the environment in the right kind of way and with multiple copies, can be observed on the macroscopic scale. That rules out various kinds of quantum information. What's left are what Zurek calls "pointer states". These are what we observe classically.

So the classical view of the universe is determined by the states that survive transmission through the environmental information channel. Hence the darwinism: it is only possible to observe the states that are fit enough to survive this process of transmission.

It's a sort of self-evident idea once it occurs to you, but it has the gift of giving a sort of intuitive basis to the idea of de-coherence (an idea I've always struggled to get my mind wrapped properly around).

Of course all lovely models need to be tested to see if they're useful for making predictions. (String theory is one of those lovely models that has yet to actually make a prediction that can be tested.) The news from last week is that researchers have managed to find a mechanism to test Quantum Darwinism to a stronger physical footing:

"[R]ecently, 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.

[...]‘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."

From here.

So, assuming this published result survives peer-review and other tests, we may actually have something exciting here.

What I personally find so interesting is this idea that it the states which propagate to the classical realm are the ones that are suited to do so. The ones that don't, don't.

Science (at least since the writing of Popper) is based on the idea that claims made by ideas are adjudicated in the lab. What the lab test supports is what is accepted. In other words the lab bench becomes the referee between competing theoretical world-views of the Universe. Once the lab bench has spoken, we know which branching path to choose to be able to push the boundary of knowledge further out.

In the Church, we have a similar situation with many different bodies making competing claims about God and about the nature of Truth. How can we decide which one is worth investing in? Which one is right?

I've wondered from time to time if we might think about this question the same way as we do Quantum Darwinism. The Church with the correct understanding of reality is the one that survives and is sustainable. The one that doesn't is naturally selected out.

The most obvious objection to the idea is that it would seem to imply that the secular world is then seen as the referee of the Bible. But that's true anyhow isn't it? We believe the biblical witness to Jesus to be both true and timeless. If information comes along that (once verified as being accurate) seems to contradict the biblical teaching, we re-adjust our interpretation of the teaching. (It's not so much that we re-adjust our interpretation, but that we have to find a way to incorporate the new information into a new expanded understanding of what the Bible teaches.)

The alternative to doing this is to deny the new verified information. (Sort of like the Creation Museum does in its almost frantic attempt to hammer scientific information into a form that will not cause us to expand our understanding of the creation accounts.) In a country which is seeing the rise of more and more "Anti-Science" even to the point where it's nearly a political party, this is an attractive alternative to many.

If God is really present in reality, and the Church's life is really animated by the presence of the Holy Spirit, then this idea that the Churches which propagate in time are the ones with the correct understanding isn't terribly surprising. The closer you hew to God's revealed truth, the more ancient and more future proof you become.

I guess in a nutshell this isn't really anything new. It's just a restatement of the biblical teaching of Rabbi Gamaliel in Acts. If the Church is of God, it will survive. If it is not, it will naturally whither.

If this is true, I hope it gives us all pause.

Twitter polling data as good as traditional methods

Here's an interesting use of social media, one that seems obvious once it's suggested, but not one I would have imagined. By aggregating large numbers of Twitter "tweets" researchers are able to relatively quickly measure broad approval or disapproval of ideas or public figures.

Science Magazine reports:

"A common complaint among people sucked into the ‘Twittersphere’ is that no one reads their posts. A team led by Noah Smith, a computer scientist at Carnegie Mellon University in Pittsburgh, Pennsylvania, didn’t have time to read them either. But at least the researchers put that massive pile of verbiage to good use: With an average size of 11 words, the 1 billion tweets posted in 2008 and 2009 add up to an impressive cultural data set. The team used text-analysis software to detect tweets pertaining to various issues—such as whether President Barack Obama is doing a good job—and measure the frequency of positive or negative words ranging from ‘awesome’ to ‘sucks.’

The results, which will be presented 25 May at a computer science conference in Washington, D.C., were surprisingly similar to traditional surveys. For example, the ratio of Twitter posts expressing either positive or negative sentiments about President Obama produced a ‘job approval rating’ that closely tracked the big Gallup daily poll across 2009. The president’s approval slumped over the course of the year in both. (The correlation between the two was an impressive 79% when the Twitter data was averaged across chunks of several days.)

By tracking the frequency of positive or negative sentiments about people’s financial well-being—filtering for posts about saving and spending—the Twitter data also reproduced trends in some classic economic indicators such as consumer confidence."

Read the full article here.

Google probably has some similar sort of capability given the number of blogs, email and searches that they can data mine. I wonder if they've thought about monetizing the results and trying to compete with traditional polling agencies.

Or I wonder if traditional polling agencies have thought about reaching out and buying access to the Twitter Fire Hose feed (the full stream of posted data) as a way of supplementing their research given the difficulty in reaching young people by phone. (A common concern in the last presidential election.)

At the very least, a concurrent analysis of the twitter and social media feed could provide a useful "sanity check" of the traditional political poll; something that would be valuable when the results you find are surprising.

It would also be a relatively inexpensive way for organizations like the Church to be able to get access to broad based feedback to initiatives it undertakes. Say, for instance, you wanted to know if the Environment was a major concern for people in the geographic region of the diocese... or whether children's education outweighed concerns about the divorce rate. In a time of limited resources for evangelism research, this could really be helpful.

Of course that would suppose that someone opened up a public API to the data and/or its analysis. And on whether or not some interested programers would be willing to open source some analysis tools - and maybe a simplified front end for their use.

But that's not too far-fetched a scenario to imagine. It would be in keeping with other open-source initiatives.

Neat idea to think about. To what sorts of things would you want to put such a resource to bear upon?

Quantum Mechanics underlays muscle motion

I've become more and more interested in the macroscopic manifestations of quantum effects. Partly because I am thinking about the where we should properly place the boundary between the classical regime and the quantum regime, and what implications that scientific decision might have on the ways we do theology. (Remember that at my heart I'm a post-positivist. As such the question of how closely we can approach the truth is really quite important.)

I linked a while ago to reports about how researchers have extended the observed range of quantum correlations from the size of the typical bucky ball to now micrometer sized objects composed of trillions of atoms. When I taught physics I regularly pointed out that despite our tendency to think we can ignore quantum effects at the macroscopic level, simple electronic devices based on the transistors would be impossible without such effects. And now there is a paper that explains a common conundrum on biophysics by making use of a quantum state analysis. (Which will lead to some of the attendant weirdness of quantum physics when the model is extended or more fully developed.)

"Tieyan Si at the Max Planck Institute for Complex Systems in Dresden, Germany, has created a quantum model of muscle behaviour. His idea is that myosin, the molecular motor responsible for muscle contraction, is essentially a quantum object and that its behaviour is best described by quantum mechanics.

The business part of muscle fibre consists of actin, which can be thought of as a rope, and myosin, which is a molecular motor which works rather like a tug-of-war team. Electrical stimulation sets the tug of war teams into action, frantically pulling their ropes and causing the muscle to contract. The actual force a muscle produces is the result of many myosin motors pulling and relaxing, although not necessarily in concert.

The challenge for theorists is to work out how these molecular motors generate the force and relaxation curves that occur in real muscle. These are well studied in systems as diverse as mammalian heart muscle and insect wings and biomechanicists have long known that different types of muscle and muscle action produce different force curves. For example, contractions that are quickly released have a different force signature to slowly release ones. Explaining this with a single classical theory is not easy.

Si's approach is simply to assume that each myosin motor is a quantum object that can form two shapes and that the switch between these shapes causes a contraction. In other words, it has two states. (He also looks at a system in which myosin has three states.) Myosin switches to one state by absorbing energy and relaxes by emitting it and the combined effect of all the switchings determine the behaviour of the fibre.

A muscle fibre, then, is simply a chain of these quantum objects, for which it is possible to derive a mathematical object known as a Hamiltonian that describes the behaviour. The question that Si addresses is that what kind of force-relaxation curves does this Hamiltonian lead to."

Read the full article here.