Theism and Materialism

In Chapter 2 of Mind and Cosmos by Thomas Nagel, the author explores the typical positions held by proponents of theism and by proponents of evolution.  His focus is sharpened by analysis of the different ways that each point of view attempts to make sense of human beings who are part of the world that ought to be intelligible to us.

According to Nagel, theists appeal to a deity who is outside the natural order, but who nevertheless provides intention and directionality to the natural order and who assures us of the basic reliability of our observational capacity and our reasoning ability.  It is a reassuring position at the expense of requiring a power outside of the natural order.  It suffers from a lack of any serious attempt to make human beings intelligible from within the natural order.

Evolutionary naturalists, on the other hand, claim that humanity is intelligible from within the natural order based on science and reason.  But, again according to Nagel, the problem is that both science and reason are the products of evolution and we have no authority outside of ourselves to substantiate the reliability of our understanding of science.  In Nagel’s terminology, evolutionary naturalism undermines its own claim of reliability.  Ultimately, the evolutionary explanations fail because the science that we possess has failed to explain consciousness and therefore failed to explain why we should trust the judgments arising from our consciousness.

I think Nagel is stretching too far for a criticism of the evolutionary point of view.  Its main problem is the inability for science to explain consciousness.  To find fault for the inability of evolution to provide reassurance that our reasoning is sound is the same criticism that can be applied to the theist position.   Both positions are based on faith!  Theists have faith in God based on a religious community and Darwinian evolutionists have faith in science based on the scientific community.  If anything, the evolutionary point of view has the advantage in that the scientific community is generally more unified and disciplined than the religious community.

The primary distinction between the two points of view, then, is the position and importance that each assigns to humanity.  Theism relies on a power outside the normal purview of science to explain and give meaning to human life and consciousness while evolution relies solely on current science at the expense of diminishing any essential or transcendent importance for human life and consciousness.

Nagel is searching for middle ground.  He wants an explanation for consciousness that does not rely on a power outside the natural order.  At this point in his book, I think he fails to see that any such explanation will be relying on faith in something.  Whether that something is science or philosophy or some combination, it will still be the object of faith.  Given the constraints on his search that there can be no power outside the natural order, his explanation would not be able to claim any more authority than evolutionary materialism.

From my point of view, a form of theism that provides a way for God to work through the natural order provides the best alternative.  The importance and discipline of science is maintained and modified so that human life and consciousness have access to transcendent power for guidance and assurance.

Scientific reductionism ends at the quantum boundary, so the assumption of transcendent consciousness working at the quantum level provides for the needed adjustment to science while maintaining the entire scientific edifice based on empirical evidence and reductionist explanation.  And there is scientific evidence for an order producing power working at the quantum level.  This evidence is being developed by the nascent scientific discipline of quantum biology.

The strongest evidence to date comes from quantum action during photosynthesis, but I expect much more evidence as quantum biology matures.  After all, isn’t all of physics based on quantum action?  The only alternative besides dualism would be a view that posits new scientific principles acting at the biological level.  But, it seems to me that there is too much continuity between chemistry and biology.  That continuity leaves little room for wholly new principles to be plausible.

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The Evidence from Physics and Cosmology (Part 3)

Quantum Uncertainty

So far in my discussion of the scientific evidence for a rational power at work in the universe, I have relied heavily on the orderliness inherent in the mathematical laws of physics that model nature’s governance of the world.  I have written about the orderly application of the laws of atomic physics during the creation of the universe.  I have written about the remarkable correlation between the abstractly ordered mathematical world of theoretical physics and the empirical world of observation.  I have presented the randomness that we observe as a form of incomplete knowledge.  Though I didn’t emphasize it, that incomplete knowledge is one of the fundamental laws.  It is called the Heisenberg uncertainty principle and was itemized as Leonard Susskind’s third universal laws in my previous post.

But there was also another kind of uncertainty.  This second kind of uncertainty is based on nature’s involvement in every transfer of energy that takes place in the universe.  Quantum physics is one of Roger Penrose’s ‘SUPURB’ theories and it calls for the orderly evolution of quantum states until some final measurable state is chosen by the universe.  The mathematics is complicated, but precise.  The theory has mathematically confirmed the measured magnetic moment of the electron to about one part in one billion.  The magnetic moment measures the reaction of an electron’s magnetic field (caused by its spin) to an external magnetic field.  This effect will cause the electron’s spin to precess, like a spinning toy top.  The precision of the correspondence between theory and experiment is like measuring the distance from New York to Los Angeles to the width of a human hair!

Even though quantum theory is based on superposed quantum states (the idea that a particle can be multiple places at once, for example), we have good reason to believe that these superposed states never rise to the level of large objects (for example, Schrödinger’s cat).  This implies that some decision process is taking place in what has been traditionally called “the collapse of the wave function:” the superposed states suddenly jump to a state that conforms to the desired measurement but is based on the probabilities associated with the superposed states. And this happens even if there is no measurement being made in the scientific sense.  In the Schrödinger’s cat example, the very hypothetical superposed states of alive-cat and dead-cat carried with them each a 50% probability.  The question that I will explore in this part is to what extent that decision process can be considered random and to what extent can it be considered coherent.

First of all, we can dispense with one kind of randomness quickly.  This is the randomness due to incomplete knowledge and, as mentioned above, all of our knowledge is incomplete due to the uncertainty principle.  There will be, in any experimental situation, quantum states in the environment that the calculations cannot consider, either because they are too numerous or because we are theoretically limited in what states can be measured accurately.  I see no power in this type of randomness to create the kind of order that we observe in the universe.

One might think that this would be the end of the discussion, but there are natural quantum processes that demonstrate coherence and order.  We are aware of these powerful natural processes because of two scientific discoveries.  Let’s see if those discoveries will give us some clue as to how to proceed.

One of the surprising discoveries of the twentieth century based on quantum physics was the laser.  Today, lasers are used in many everyday applications.  They are used to record and playback compact discs of various types; they are used to read bar codes on products purchased at retail stores; they are used to measure distance and speed; they are used as pointing devices, surgical instruments and even as potential military weapons.

The surprising property of lasers on which I want to focus is that they produce coherent light; that is, light of a single color or frequency with all light particles (photons) in synchronization with each other.  This is highly ordered light, with entropy near zero.  The ability of lasers to produce highly coherent light is due to a special quantum physics property that only bosons possess.  Light particles are one of a number of elementary particles called bosons.  You may have heard of the Higgs boson for which evidence has recently been discovered at the Large Hadron Collider (LHC) near Geneva, Switzerland.  All other ordinary matter – matter that makes up virtually all of the stuff necessary for life, for example electrons, protons and neutrons – are fermions.

Aside from the major distinction between light and matter, there is another very important difference between bosons and fermions.  The distinction is related to another fundamental law of physics called the Pauli Exclusion Principle.  This principle states that two fermions cannot share the same quantum state.  Without this law, ordinary chemistry would not be possible; life would not be possible.  The Pauli Exclusion Principle is the explanation for why electrons exist in different orbits in atoms. Because electrons are in different orbits, the elements have different chemical properties, mostly due to the electrons that are in the outermost orbit.  This is why 2 atoms of hydrogen combine with one atom of oxygen to form water.  Hydrogen has one electron and one open slot in its outer orbit whereas oxygen has two open slots available in its outer orbit.  The two electrons from the two hydrogen atoms exactly satisfy the one oxygen atom’s tendency to fill up the outer orbit.  Water is highly stable with both hydrogen and oxygen sharing electrons to fill each other’s open slots for electrons.

Light particles (photons), like all bosons, do not obey the Pauli Exclusion Principle and they can share the same quantum state.  And that is why lasers are possible.  Lasers work because photons actually prefer to be in the same quantum state as other photons.  It is very important that the photons are produced synchronously. If photons are produced by heat, for example in an incandescent light bulb, they are produced at different energy levels.  Different energy levels mean different colors and different frequencies – hence incoherent light.  Lasers work because they use partially silvered mirrors to reflect light photons back and forth across a suitable material until all the emitted photons are synchronized.  The mirrors allow time for synchronization to happen.

If energy transmitted by light particles can be synchronized, what about energy transmitted through matter?  Since fermions are prohibited from being in a synchronized state, they cannot transmit coherent energy.  Or can they?  Consider the phenomenon of superconductivity.  Superconductivity does not yet have a household application, but it is very useful in certain areas where very strong and concentrated magnetic fields are needed.  Superconductivity is the free flow of electricity through a conductor which is usually cooled to a very low temperature.  Electricity flow is accomplished by electrons (fermions).  So how do low temperatures produce coherent electron flow?

The beginning of the answer is that electrons have a property called spin.  Spin is the property responsible for magnetism in permanent magnets.  Iron has three filled orbits of electrons with the outer orbit containing two electrons.  Those two electrons in the outer orbit are allowed to have the same spin.  The spin of the electrons in the inner orbits will cancel each other, leaving the total spin effect to the outer orbit electrons.  If iron is placed in a magnetic field, the spin of all the outer orbit electrons will align and the whole iron atom will have a net magnetic field.  Iron will retain the magnetism because of its crystalline structure.  Heating will generally cause iron to lose its magnetism through the strong molecular vibration caused by heat energy.

It is one of those strange quantum physics rules that measured spin has only two values.  Let’s say we want to measure electron spin in the “up” direction.  The answer will always be either yes or no.  That is, the spin will always be up or down.  This will be true no matter what actual direction we call “up.”  If we first measure spin in the up-down direction and separate all spin up electrons from all spin down electrons, we can perform another measurement on, say, the spin up electrons.  If we measure them again for spin up then the answer will always be up.  100% of the time the second measurement will agree with the first.  But if we measure the spin in the left-right direction, then we find that half will have spin left and half will have spin right.   This strange property of spin is shared by all fermions.

Bosons, on the other hand, do not share this spin property.  Fermions have what is called “half spin” and bosons have “integer spin.”  The measured spin of fermions is stated in units of one-half whereas the boson spin is stated in units of integers.  Photons, in particular, have spin one.  They do not divide into spin up and spin down.  Light can be polarized, but that is another story for another time.  So perhaps a way to cause electrons (fermions) to behave like bosons (light) is to cancel out their spin property.

That is in fact what happens in the phenomenon called superconductivity.  In the right material and at very cold temperatures, electrons can pair up so that one spin-up electron associates with a spin-down electron giving an overall spin of zero.  The electron pair can act like a boson and flow coherently and without resistance through a conductor.  The conductor must remain cold enough to prevent thermal molecular motion from splitting up the electron pair.  These pairs of electrons are called “Cooper pairs.”

As long as I’m writing about coherent light and electrons, I should mention one other interesting phenomenon: lasers can be used to cool atoms to a very low temperature.  Thus, the low entropy of the laser can be used to reduce the entropy of matter.  This does not violate any laws of thermodynamics since entropy must be increased elsewhere in order to decrease entropy in a specific location.  However, the ability for a process to decrease entropy at a particular location is very important to life.  Both the efficient concentration of energy for fuel and the remarkable ordering of the genome are key factors in the evolution of life.

Therefore, in the example of lasers, superconductivity and laser cooling, nature has given us a hint of where to look for processes that are essential for life.  The place to begin looking involves light interacting with matter.  Particularly, we should be looking for evidence that coherence in the light / living matter interaction will result in some concentration of energy or increase in order beyond what we might expect for inert matter.  Not surprisingly, that points us to photosynthesis.

For comparison, we should consider what happens when sunlight interacts with ordinary inert matter.  Consider a particle of light, a photon, traveling from the sun to earth.  That trip takes about 8 minutes.  The peak energy emission from the sun is propagated by photons in the green color range with a wavelength about .5 micrometers.  For comparison, the width of a human hair is about 25 micrometers or 50 times larger.

When the photon strikes a surface and is absorbed, it will cause the molecules to vibrate slightly faster resulting in heat.  Over the course of a day, the direct sunlight will heat up materials significantly.  But at night, the heated material will cool by emitting infrared photons.  If the heated material is about 70 degrees Fahrenheit, the emitted radiation will have a wavelength of approximately 10 micrometers.  The emitted wavelength is about 20 times longer than the sunlight arriving from the sun, so it will require about 20 times as many photons to dissipate the same energy as was absorbed.  The increased number of photons required to dissipate the sun’s energy results in an increase in entropy.

Now, what happens when a photon of sunlight is absorbed by the chlorophyll in a plant?  First of all, some of the highest energy photons are reflected because chlorophyll is green and therefore reflects green light.  Chlorophyll does not absorb green light, but strongly absorbs blue and red light.  The real surprise is that the transport of the blue or red photon through the Chlorophyll molecules is done with near 100% efficiency.  Virtually no energy is lost as heat.  I wrote about this capability in a previous post (see https://quantumveil.wordpress.com/2012/03/06/quantum-coherence-in-photosynthesis/).  I overstated the efficiency in that post since I included food production, but the essential point is that the transport of the photon’s energy from initial point of contact in the chloroplast to a molecular structure called the “reaction center” is accomplished without heat loss.  The reaction center is where the process of using sunlight energy to convert water and carbon dioxide into food begins.

The experiments that have been done to confirm this photosynthetic process also show that the efficient conduction of sunlight to the reaction center is associated with quantum coherence.  The strong implication is that quantum coherence assists the lossless transfer of energy to the right location for food production.  Without such effects, the normal expectation would be for some of the sunlight energy to escape as heat energy.  By keeping the chlorophyll as cool as possible, the chlorophyll is able to efficiently convert sun energy into food.  That keeps entropy low.  There are other processes that aid in cooling as well, but the evidence for quantum coherence in this process is a significant fact.

Because quantum coherence is involved in the transport of sunlight energy in photosynthesis, it is not out of the question that it is involved in other life processes.  All biochemical reactions involve both photons and electrons, the key components of quantum process.  The overall conversion of sunlight into food involves a local decrease of entropy.  Water is split apart to form hydrogen and oxygen and the hydrogen combines with the carbon from the carbon dioxide to make carbohydrates for food.  This is a concentration of energy and an increase in order that can be described as negative entropy.  It does not violate the law of increasing entropy because entropy rises elsewhere to compensate.  But the local decrease in entropy means a great deal to life processes.  Without the sugars and oxygen that plants produce, life on earth as we know it would not be possible.  We should all thank a plant for its miracle of negative entropy.

Analysts of the photosynthesis / quantum coherence experiments have described the phenomenon as a kind of quantum calculation.  Continuing with the computer analogy, any calculation, if it is to be useful, requires the result to be reported.  In the case of photosynthesis, the “report” is an actual decision on the path the photon should take to its destination.  I have generalized this understanding: any transfer of energy requires a decision by the universe.  That decision process is not random.  Energy must be conserved.  Momentum must be conserved.  Charge must be conserved.  Even quantum states must be preserved if the same state is measured again.  In the case of photosynthesis, there may be multiple paths to the reaction center, but it would not matter which path is chosen as long as the chosen path did not result in heat loss.  This is what I mean by “not random.”  There is uncertainty but not randomness.  Pure randomness results in increased entropy and all living organisms rely on an inherent ability to reduce or conserve entropy, or minimize entropy increase.

The best current theory is that quantum coherence enables calculations regarding the energy landscape of the molecules involved.  In photosynthesis, the thinking is that quantum coherence allows the photon to follow a “downhill” energy path to the reaction center.  This would strongly imply that quantum coherence makes calculations about the laws of physics.  We shall see more evidence of this type when we cover the phenomenon called “protein folding” where biological proteins fold into a shape that minimizes their energy.  I am using computer terminology because this is possibly the best way for people to think about the power of rational agency.  But, like any analogy, it can be stretched too far.

What kind of power could be responsible for this type of activity?  I think the evidence points to a rational power that transcends time and space.    I describe it as transcending space and time because quantum phenomenon is non-local:  it instantly affects widely disbursed particles.  The non-local properties of quantum theory have been established by several tests.  One such experiment was Alain Aspect’s 1981 test of Einstein’s EPR paradox in which Einstein attempted to show that quantum theory was incomplete.  He described the phenomenon, which he clearly thought was impossible, as “spooky action at a distance.”  Another recent test confirmed John Archibald Wheeler’s delayed choice experiment.  This 2007 test was also performed by a French team that included Alain Aspect.  The tests performed by the French teams were done using polarized light photons, but the results have been confirmed by additional experiments.

Since both the quantum phenomenon and the tests are complicated, perhaps the best way for me to describe the results is through analogy.  Let’s recall the ability of electricity to flow without resistance through a wire that has been cooled to near absolute zero.  Recall that under these special conditions, two electrons with opposite spin associate with each other and form a composite particle that has boson-like properties.  The composite particle, called a Cooper pair, can act like a boson in sense that that the pairs of electrons prefer to be in the same state as other Cooper pairs.  That means that the Cooper pair of electrons can be in a coherent state with other pairs and can move synchronously through the conductor.  The two electrons in a Cooper pair are called “entangled.”

Now, imagine that we can separate the entangled pair of electrons without disturbing their entangled state.  Progress has been made on actually performing this trick.  One of the quantum rules is that the spins must be in opposite direction, even after separation.  Suppose that a measurement of spin is done on one of the two electrons.  That measurement will cause the other electron to immediately jump to the opposite spin direction.  That will always happen, no matter what direction is chosen.  According to quantum theory, this will happen no matter how far the electrons are separated, though in the experiments with photons, the photons are generally only separated by a few meters.

This quantum trick is like a magician who puts three colored balls into one box and three balls of a different color into a second box.  Let’s say he puts a red, green and white ball into box one and he puts a blue, yellow and black ball into box two.  The boxes are separated; maybe even placed in different rooms, or even at great distance from each other.  A ball is drawn at random from box one and a ball is drawn at random from box two.  In every case, if a red ball is drawn from box one then a blue ball is drawn from box two; if a green ball is chosen from box one then the yellow ball comes out of box two; similarly for the white and black ball.  Every time the trick is performed, the ball drawn from box one appears to cause a particular ball to be drawn from box two.  Imagine the same trick with 100 balls or 1000 balls; that is the power of quantum entanglement.

Entangled particles have the power to instantly communicate a change in state to other particles.  This communication can cover great distances and occurs instantaneously.  This has led some to claim that the instantaneous communication violates the spirit of relativity.  While there is some truth to that claim, it is nevertheless impossible to use this quantum ability to instantaneously communicate to actually send a coded message.  Causality is not violated.  This appears to be another situation where the universe has an apparent ability to bypass causality, but we are prevented from using that ability to alter history.

Nor can we claim that entanglement is a rare event.  It is the norm.  This has led some to say that the entire universe is entangled.  I don’t know if that can ever be confirmed, but if entanglement can affect particles a few meters apart, then it can certainly affect biological molecules at much closer range.

This is why I think that scientific evidence supports a conclusion that a decisional, rational power is at work in the universe, a power that is conducive to life.  That power is at work in every transfer of energy because a decision must be made as to which of the quantum possibilities will be chosen.  That decision is not random; it follows certain well established rules that are the foundation of physics.  The best characterization of the decision process is that it is a quantum calculation.  It appears random to us because we do not and cannot know all the variables that affect any given particle.  In particular, we cannot know all the quantum entanglements by which any given particle is constrained.  I think this is the best explanation as to how life and consciousness can develop from ordinary matter: protons, neutrons, electrons and photons.  There is no alternative explanation as to how the forces of electromagnetism, the strong and weak forces, and gravity can accomplish the amazing reduction in entropy that exists in living organisms.

The Evidence from Physics and Cosmology (Part 2)

My previous post describes the evidence for a rational agent based on an ordered universe created by the “Big Bang”.  But if the laws of nature are so orderly, where does unpredictability come from?  Where does uncertainty come from?  We will need to know more about what we mean by “laws,” and why some of those laws might allow for some sort of non-deterministic behavior.  Might some non-deterministic activity be evidence for an ongoing role for a rational power in the universe?  But first, what are our most certain assumptions about nature?  What is it that all of physics depends on?  Leonard Susskind specifies three unconditional laws of nature (from The Black Hole War):

  1. The maximum velocity of any object in the universe is the speed of light, c. This speed limit is not just a law about light but a law about everything in nature.
  2. All objects in the universe attract each other with a force equal to the product of their masses and the Newton constant, G. All objects means all objects, with no exceptions.
  3. For any object in the universe, the product of the mass and the uncertainties of position and velocity is never smaller than Planck’s constant, h.

Susskind emphasizes, “There is no dispute . . . .  They apply to any and all things – everything.  These three laws of nature truly deserve to be called universal.”  For the really picky reader, there are some additional qualifications that probably need to be added, but I’ll ignore those now to keep things as simple as possible.

To these three unarguably fundamental laws, Susskind would probably add the conservation of energy (energy is neither created nor destroyed; mass being a form of energy due to Einstein’s famous equation, E = MC2); the conservation of charge (charge is neither created nor destroyed; electrons and protons are examples of charged particles); and surprisingly, time reversibility or conservation of information.   Susskind maintains that it is fundamental to the laws of physics that, in addition to predicting the future, the laws do not allow for an ambiguous past.  In other words, information about the prior states of a system is never lost.  He has successfully argued this point with Steven Hawking and apparently won. Roger Penrose appears to be a lone holdout in this debate about conservation of information.   Time reversibility will prove to be a paradoxical factor in the laws of physics.

Speaking of Roger Penrose, he would probably add to this list as well.  He rates our best scientific theories as ‘SUPERB’, ‘USEFUL’, or ‘TENTATIVE’.  In the ‘SUPERB’ category, he places Einstein’s theory of relativity (both special and general relativity), quantum theory, Newton’s laws of motion and law of gravity, and Maxwell’s theory of electromagnetism.  Into the ‘USEFUL’ category go the standard model of particle physics and the Big Bang theory.

Let’s look at some of the implications of these fundamental laws of physics for an orderly, rational world.  The first fundamental law stating that the speed of light is the maximum speed for any observer is included in Einstein’s special theory of relativity.  There are some remarkable features of the special theory of relatively.  The constancy of the speed of light for all observers leads to conclusions that distances along the direction of motion must contract and time must slow down for any system that is moving with respect to another system.

This effect is symmetric with respect to two systems that are moving past each other at a uniform speed so that observers in each system will conclude that the other system is measuring shorter distances and slower times.  However, if one system reverses direction, this implication of the special theory of relativity will have permanent consequences.

For example, if identical twins are born on earth and one of them is placed on a rocket to a nearby star and that rocket is moving at a speed close to the speed of light, then the space traveler twin will return to earth younger that his or her sibling.  The effect of time slowing down is made permanent by the reversal of direction of the rocket.  The space traveler twin will experience acceleration and deceleration that will break any motion symmetry between the two twins.  This is called the twin paradox.

The surprise is that each observer in motion has his or her own time frame.  With the twin paradox, it is possible for anyone who is willing to travel fast enough to move forward in time.  The space traveler will return to earth at a time in the future compared to the traveler’s own clock or calendar. If one is willing to travel fast enough and far enough, one could actually return far into the future.

This effect has been measured in particle accelerators and in the effects of cosmic rays that strike earth’s upper atmosphere.  The high energy cosmic rays that strike high altitude molecules will create exotic particles (muons) which normally decay so quickly that few would reach the earth.  However, some of these particles are moving so fast that time is slowed down to the point where more of them can be detected at a lower altitude.

You might wonder if it’s possible to travel forward in time, is it also possible to travel back in time?  The answer is no.  Backward time travel world require traveling faster than the speed of light which is prohibited by the Einstein’s special theory of relativity, and Susskind’s first fundamental law above.  That is a good thing because if one could travel back in time, causality could be violated: it would be possible to alter history (for example, think of the movie, “Back to the Future”).  It is not even possible to send a specified signal at a speed faster than light.  If one miraculously had such a device that could send a signal at greater than light-speed, and if that signal could be relayed back to its source, then a report of a future event could be received in the past thereby providing the option of avoiding the future event!

Even though special relativity makes time relative to each moving observer, it guarantees that time will always move forward, never backward.  It thereby guarantees causality:  causes will always precede effects.  Causality is one of the fundamental guarantees of a rational universe.

From time to time, there are scientific theories or experiments that appear to show that the universe has the possibility of violating causality.  One such possible implication arises in general relativity in the theory of black holes – stars so massive that not even light can escape.  Another implication of a possible violation of causality arises in the quantum theory of entangled particles.  Both of these situations imply that the universe has capabilities that are not made available through any normal activity.  But even if the universe has the ability to violate causality, that ability is not available to its inhabitants and it is still not possible to send any message back into the past.

In fact, the mere possibility of a violation of causality in relation to black hole singularities led Roger Penrose to propose a cosmic censorship hypothesis which states that it is not possible to observe any physical process that will lead to a violation of causality.  The sort of determinism in which time always flows forward is a key property of this universe.  Yet this property is in direct conflict with Leonard Susskind’s assertion that the laws of physics must be able to be reversed.  How will this tension be resolved?

Susskind’s law concerning the conservation of information is based on a fundamental assumption that the laws of physics are unambiguous with regard to the past.  This is sometimes stated that the laws of physics are still true whether time runs forward or backward.  This feature of scientific theory is necessary if we are to project events backwards to arrive at a beginning point.  The obvious question then is why don’t we ever see time running backward?

In a previous post, I have framed my discussion of rational agency in terms of a contradiction between two concepts.  One idea is that the universe is fundamentally governed by deterministic laws which include a provision for random action. I have called this concept materialism, but its main determining factor is a randomness which accounts for any observational results that are not strictly predictable.  The other concept I have called a rational agent, but its main determining factor is directed, rational action that conforms to the deterministic laws.  I have stressed that these are two extremes and that the truth might lie somewhere in between.  So far in my discussion on science, I have described the Big Bang creation of the universe and special relativity.  Both of these narratives intimately involve matter.  Even if the rules governing matter are rational and rigorous, why does that imply a rational agent?  And how do rational laws result in uncertainty?

All of the theories listed above – from relativity to quantum theory – are models of physical reality.  That is, they describe physical reality using mathematical equations along with constraints or principles that are applied to the analysis of physical reality.  The mathematics associated with each theory is an integral part of the narrative that explains why the theory is true.  Without such a narrative, doubts would immediately set in if there were anomalous observations.  For a well-tested and mathematically consistent theory, there are strong reasons to doubt the anomalous data.

For example, not too long ago some observations suggested that neutrinos could travel faster than light.  There was an experiment associated with the Large Hadron Collider (LHC) near Geneva, Switzerland in which neutrinos were timed at about 60 nanoseconds faster than a light beam going a distance of 450 miles.  If that observation had proved true, it would have been a significant violation of special relativity.  The problem was eventually traced to a GPS synchronization issue between the two clocks used to time the trip, but resolution took several months.  This episode illustrates both the confidence generated by a mathematically consistent, well tested theory and the provisional nature of any theory.  The provisional nature of scientific evidence is one reason for looking at a gestalt of the evidence rather than relying too much on any one result.

As mentioned above, the special theory of relativity describes the way that different observers, moving at different speeds will view the same events.  Mathematical equations define how clocks and rulers change when moving at high speed.  These changes have been observed in particle accelerators:  particles accelerated to high speed flatten out, like a pancake, and particle lifetimes increase in accord with special relativity.

The naïve question won’t go away:  how is it that matter in the form of very small particles knows how to obey the laws of special relativity?  Unless one thinks that the real world is a computer simulation (and some actually do think this), how do ‘inert’ particles know how to behave under the laws of physics?  Either the particles are not so ‘inert’ or there is a rational power that enforces the laws of physics, or both.  This is part of my evidence for panpsychism.  Matter and consciousness are intimately bound together.  Matter is knowledge made manifest.  Our mathematical theories hint at the connection.

What our best theories don’t tell us is how physical reality really works, or as Stephen Hawking says (quoted by Jim Holt): “What is it that breathes fire into the equations and makes a universe for them to govern?”  Or as someone once asked, “How does the electron know to follow the rules defined by the equations of magnetic force?”  Holt adds, “How do they [the equations] reach out and make a world?  How do they force events to obey them?”  Our scientific theories are rational models of how the universe works.  As such they are evidence for a rational process at work in the universe.  But they are not the actual power that enforces the physical laws.  That power lies outside our knowledge, but our best theories are pointers or signposts that indicate that the power is real.

My answer to these questions is that it is a rational agent that breathes the fire into the laws of physics and makes out of them a coherent world in which to live.  In order to understand how that happens without recourse to any supernatural power, I will need to describe two kinds of uncertainty or unpredictability that are present in our empirical view of the universe.

The first kind is easily dispensed with.  It is what Leonard Susskind calls experimental “sloppiness.”  I think that is a bit unkind because what he means is the inability to keep track of all the minute details that are necessary for the prediction of a result.  Think of a drop of ink placed into a glass of water and how it spreads out with apparent randomness.  Theoretically, if we knew the positions and velocities of all the particles we could predict the spreading.    Not only that, but we could reverse the spreading so that the dispersed ink coalesced into a drop and popped out of the water!  This is what Susskind means by “time reversal” or conservation of information.  But before information can be conserved, we have to know what that information is, and in complex systems, it is impossible to know all the variables that we would need to know.

What is important in the conservation of information is that it be theoretically possible to reconstruct the past, not that it ever be practical to do so.  This type of unpredictability is caused by the observer’s lack of complete knowledge.  But, as far as I can tell, there is no ordering power in lack of knowledge.  So this type of uncertainty is not very interesting.  (But I don’t mean to denigrate such useful scientific tools as stochastic modeling!)

Much more interesting from the perspective of conservation of information is the uncertainty that comes from quantum physics.  This is a completely different kind of uncertainty.  It is an unpredictability caused by the universe’s direct intervention in the outcome of any transfer of energy.  If you’ve heard of Schrödinger’s cat or the “collapse of the wave function,” you already know what this is.

Schrodinger’s cat is the archetypal and somewhat hackneyed example.  A live cat is placed in a box with a poison vial which can be broken by a single well-aimed photon that passes through a half-silvered mirror.  A photon passing through a half-silvered mirror has a 50% chance of being reflected and a 50% chance of transmission.  So there is a 50% chance that the vial will be broken and the cat poisoned and a 50% chance that cat will live.  The example concludes by speculating that we won’t know if the cat is alive or dead until we look in the box.  But, more dramatically, the story raises the question of whether the cat exists in a quantum superposed state of half-dead and half-alive!  This is what distinguishes the quantum example from the first type of uncertainty which is due to lack of complete information:  Schrodinger’s cat would be both dead and alive.

We never observe half-dead cats; so most physicists believe that quantum superposition never rises to the level of cats or anything else as big as a cat.  That means that the photon wave function must collapse to a definite state before whole cats get involved.  Most people believe that the cat is either dead or alive before the box is opened.  (Lest anyone be troubled as to why the universe might get involved in choosing life or death for a cat, remember, it was the hypothetical scientist who set up the experiment!)

Oddly enough, science has not been able to resolve this deep puzzle about quantum physics.  Lee Smolin, in The Trouble with Physics, calls it one of the “five great problems in theoretical physics.”  Roger Penrose has written at least two books to put forward his theory that there must be some objective reduction in the wave function based on the laws of physics.  The main reason that this problem has resisted solution is that attempts to test when the wave function collapses typically cause the wave function to collapse.  There may be indirect evidence, however.

The indirect evidence to which I am referring is that the universe, by choosing an outcome in every transfer of energy, is actually adding knowledge to an observable process.  We shall need to look for processes at the quantum level that concentrate energy or concentrate information that would not be expected from the law of increasing entropy.  Some of this evidence will be found in my next post dealing with quantum coherence and quantum entanglement.  The remaining evidence will be described under the topic of evolution when I look at biological processes that increase order and concentrate energy.

Supplementing and partially compensating for the lack of direct evidence is the philosophical perspective of objective realism.   There are strong reasons to believe that the wave function does collapse even if there is no observer.  This is the quantum physics version of the conundrum, if a tree falls in the forest and no one hears it, did it really fall?  There are strong reasons to believe in the reality of quantum states and strong reasons to believe that the universe picks one of the possible quantum outcomes, but the evidence is circumstantial.

If one takes the point of view that the collapse of the wave function is a real event that is initiated by the universe (whether or not there are governing rules) then one has taken the position that the universe chooses one particular outcome among all the possible outcomes that are predicted by quantum theory.  That means that anytime energy is transferred, at least one choice is involved and more often many choices are required.  This is the basis for a fundamental ‘decisionality’ in the universe that underlies all activity.  It is this fundamental decision process that prohibits any backwards movement in time.  It is the reason that we only observe time moving forward.  And ‘decisionality’ is evidence for rational agency.

Leonard Susskind confirms this position by insisting that, in order for time to be reversed, the quantum state must not be disturbed:

“Take the photon. When we run the photon in reverse, does it reappear at its original location, or does the randomness of Quantum Mechanics ruin the conservation of information? The answer is weird: it all depends on whether or not we look at the photon when we intervene. By “look at the photon” I mean check where it is located or in what direction it is moving. If we do look, the final result (after running backward) will be random, and the conservation of information will fail. But if we ignore the location of the photon—do absolutely nothing to determine its position or direction of motion—and just reverse the law, the photon will magically reappear at the original location after the prescribed period of time. In other words, Quantum Mechanics, despite its unpredictability, nevertheless respects the conservation of information.”

In Susskind’s narrative about information conservation, I sense an underlying agreement with Roger Penrose.  It is the decision process associated with the collapse of the wave function that prevents time from running backwards and it is also part of the basic mystery of the law of increasing entropy.  In order for the fundamental ‘decisionality’ of the universe to lead to rational agency, it must demonstrate the ability to perform activities that minimize entropy.  We will see some of that evidence in my next post regarding lasers and superconductivity.

The inescapable conclusion is that the collapse of the wave function does indeed discard information: it concentrates information about the state of the universe; it eliminates possible energy states; it sets a limit on the increase of entropy.  Quantum physics began by solving a profound puzzle about the energy spectrum.  In the nineteenth century, the energy spectrum was considered continuous.  If the energy spectrum was continuous, then there would be an infinite number of energy states and any heated object would radiate infinite energy.  Everyone knew this wasn’t true, but it was Max Planck who postulated in 1900 that radiation energy was quantized in units that now bear his name.  This one simple change limited the number of energy states and reduced the hypothetical infinite energy to a finite energy that was confirmed by experiment.

If we are to truly understand how the universe works in all of its magnificence, how it is able to produce both deterministic order and adaptable life, then we need to understand any process that limits entropy or has the potential of reducing entropy.  That physical process is quantum physics.

These topics will be explored in my next post.

Quantum Coherence in Photosynthesis

Human beings are profoundly affected by quantum physics.  I have asserted this in my previous post and have used this as evidence for God who is an intelligent power behind the Quantum Veil.  So, what is the actual scientific evidence that such quantum effects occur in living organisms?  The most striking evidence to date comes from analysis of plant photosynthesis.  The amazing thing about plant photosynthesis is that it converts sunlight into food with almost 100% efficiency.  The theoretical limit for currently designed solar panels is about 40% efficiency. The solar panels that you can buy and put on your roof do no better than 15% efficiency.  In this case, learning how nature does this remarkable conversion of sunlight could help us solve our energy problem.  Go outside on a hot summer day and feel a leaf from a typical tree.  It will feel cool to the touch when other things in direct sunlight such as concrete, metal, and wood planks will feel hot.

The evidence for quantum effects during photosynthesis was published in 2007 in the Journal Nature (“Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems”, G. S. Engel, et. al., Vol. 446, page 782, 12 April, 2007).  This work was done by a team at the Lawrence Berkeley National Laboratory.  The reason that the efficiency is so high in living plants is that the entire process of transmitting sunlight energy inside the leaf takes place while that energy remains in a quantum state.  This is remarkable because there are many steps in the transmission of energy that had previously been thought to require an energy hopping scheme for transmission.  Quantum transmission is inherently more efficient than predicted by the energy hopping theory.

Photosynthesis takes place in two stages within Chloroplasts which are one part of some plant cells in the leaf.  Stage one is the light harvesting phase where sunlight energy is gathered by chlorophyll molecules.  Stage one takes place within Thylakoids inside the Chloroplasts and there are two main parts: the light harvesting antenna which gathers sunlight energy and a reaction center which initiates the chemical conversion of water and carbon dioxide into plant food.  Stage two is initiated by stage one and is the chemical production of plant sugars for food.  Stage two is fueled by energy in the form of free electrons from stage one and takes place in the body (Soma) of the Chloroplast.  Stage one is sometimes called the light phase and stage two, the dark phase.

Chlorophyll is the primary molecule used during stage one of photosynthesis.  This molecule has different types, each of which is sensitive to a broad spectrum of light color.  Overall, chlorophyll is more sensitive to the blue and red colors than to green and therefore green light is reflected, giving leaves their characteristic green color.  (An interesting side note is that when deciduous trees shed their leaves in the fall season, the color change is due to the absence of the green Chlorophyll which has been shielding the underlying colors during the growth season.  Leaves don’t really change color so much as reveal existing colors already present.)  Sunlight comes as a mixture of different colors, from low energy red to high energy violet; green is in the middle.

The light harvesting antenna inside the Thylakoids are densely packed Chlorophyll molecules embedded in protein scaffolding.  When a photon of sunlight energy is captured by the light harvesting antenna, it must be transported to the reaction center where it can initiate the conversion of water and carbon dioxide into plant food.  The main theory for the transport process prior to evidence for quantum coherence was based on Forster resonance energy transfer (FRET) theory.  The Forster-based theory proposed that the photon energy randomly hopped from chlorophyll molecule to chlorophyll molecule until it reached the reaction center.  This was a semi-classical description with few quantum effects because it had usually been supposed that quantum coherence could not last long enough in living systems for the complete transmission.

All that changed in 2006 when the Lawrence Berkeley team used advanced microscopy technology to capture data that unambiguously demonstrated long-lived quantum coherence in biological systems.  The actual experiments were performed on a popular target of research named the FMO (Fenna-Matthews-Olson) complex.  Although the initial experiments were done at cryogenic temperatures (77 degrees Kelvin), they were soon replicated, with little loss of quantum coherence, at room temperature (300 degrees Kelvin).  In these experiments, quantum coherence lasted up to 1 picosecond (one trillionth of a second), about 20 times longer than usually assumed for these biological systems.  (The original press release from the Lawrence-Berkeley Labs can be found here: http://www.lbl.gov/Science-Articles/Archive/PBD-quantum-secrets.html).

The demonstration of long-lived quantum coherence in plant photosynthesis proves it is possible for living system to make use of quantum effects.  It is still an active area of research how quantum effects lead to high efficiency of sunlight conversion.  But there is sufficient confidence in these findings that projects exploring artificial photosynthesis have been funded with the hope that one day we will have high efficiency solar power.

Plant life and animal life are the two main categories of life on earth.  Plants definitely use quantum effects to their evolutionary advantage when they convert sunlight into food.  It has been proposed that animal life also makes use of quantum effects through the ubiquitous microtubules.  While this has not been conclusively demonstrated, why wouldn’t evolution make use of every benefit at its disposal?

Quantum theory predicts some very remarkable characteristics such as entanglement, energy tunneling, and multiple state superposition.  These are all counter-intuitive properties.  Albert Einstein called quantum entanglement “spooky action at a distance”.  Energy tunneling allows particles to penetrate a so-called “impenetrable barrier.”   And quantum state superposition allows a particle to be in more than one place at a time. Superposition is the principle behind Schrodinger’s cat paradox, where Schrodinger’s pet cat is inside a box with a mechanism for dispensing poison that is triggered by a single particle.  Since it cannot be determined from outside the box whether the poison has been released, the cat is presumed to be in a superposition state of both alive and dead until the box is opened and the cat is actually observed.

There is a fascinating book on the strange and mysterious properties of quantum physics.  It is titled Quantum Enigma: Physics Encounters Consciousness, by Bruce Rosenblum and Fred Kuttner (Oxford University Press, 2006).  This book is written for the layperson and uses written narrative rather than mathematics to describe the strange quantum world.  Science cannot explain consciousness, but the study of quantum physics leads inexorably to an encounter with the nature of consciousness.  There are undoubtedly many surprises awaiting our discovery and we may find that the quantum world is the source of our remarkable experience of consciousness.