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  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.


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