Natural Selection Vs. Intelligent Design: A Physicist's Perspective

Think of a few random numbers. Numbers like 8, 12, 876, 93 ...These are random numbers in biology, and these seemingly simple numbers hold keys to the most profound mysteries of the universe--- ourselves. To be more specific (and less dramatic), not the numbers but the process through which numbers have been produced have serious implications. For example, one can ask some fascinating questions like

1. Are these numbers really random?
2. Am I likely to come up with the same numbers if asked for random numbers in the future?
3. How does our brain produce these random numbers?
4. Is it likely that the brain has just tagged a few numbers as random?
5. Is there an algorithm involving random processes like rolling dice going on unconsciously in the brain?
6. Are our thought processes free?
7. Is there such thing as free will to start with?

All of you would have rightly noticed that these are the questions for which we do not have satisfactory answers at the moment. Some of you would believe that science will ultimately find out the correct answers to these questions, and till then, there is no need to beat the bush and create hype. Most of you might not realize that science has a few answers and a few leads where a little more effort can answer some profound questions.

At the end of this post, I will propose an experiment that you can perform at home to probe your thought processes. Meanwhile, let's talk about some random processes.

Perceived randomness is not random

Let’s look for random numbers in the mechanical world out there. These are the outcome of random processes like the toss of a coin or roll of a dice. There are other random phenomena like the number of red cars crossing an interchange in a day, the number of meteorites entering our atmosphere, etc.

Then there is the output of numpy.random.rand() (or any other routine of your favorite computer language). The last one is surely not random because it is the output of an algorithm. The algorithm will produce the same numbers if it starts its calculations from the same 'seed' number. These are, in fact, pseudorandom numbers. Good for all practical purposes, but completely predictable and thus not exactly random.

Most of the randomness we experience in our lives is in fact pseudo-randomness, caused by the lack of information.

Take the other example—the number of red cars crossing an interchange. The person waiting at the interchange may find the appearance of a red car as a random process, but a person having the live traffic view of the region through a satellite will know how many red cars will cross the interchange. The process, which is apparently random for one observer, is completely deterministic for another observer with more information. This is a general feature for most of the randomness we experience in our daily life. The apparent randomness is due to a lack of information.

Now think of the toss of a coin. The result is again apparently random. But do you really think that we can fire a rocket in space and exactly determine when and where it will land on Mars but can not predict the outcome of the toss of a coin? Are the laws governing the motion of the rocket so different from the ones that determine the movement of the coin? Indeed it is not the case.

The same laws of physics prevail in two cases. The only difference is that we lack precise information regarding the dynamics of the coin when it is tossed. Not that the information is not there. We simply do not bother with the effort of retrieving it and pretend that nature has made a random decision for whatever purpose the coin was tossed. Indeed the video footage of the first few fractions of a second of a coin just tossed through a fast movie camera can decode the dynamics of the coin and can predict the outcome of the toss.

The same is true for the roll of a dice, your favorite lottery, or most of the random processes you can think of (pun intended). This is because the laws of nature we experience in our daily life ( for simplicity, Newton’s laws that we study in high school) are deterministic. If you know the initial conditions (positions, velocities) of the objects of interest and the forces acting on these objects, you can precisely determine the future dynamics of the objects. Anything appearing random in this domain is due to our lack of access to the information. The information is there. We just need better technology to record and process that information.

Casinos may run out of business in near future when our smartphones will start predicting the outcome of the dice while it is still rolling.

This means that in a couple of decades in the future, the toss of a coin and roll of a dice may not serve any more than does abacus today. We would have the required technology in our smartphones capable of resolving the dynamics of the coin in a fraction of a second and predict the outcome.

A few quick snapshots of the roll of a dice and our phones will predict the outcome of the throw. Maybe there are people making such apps right now. Maybe there are people making money in this way right now. But for more humble ones like us, a natural question is how we will play casinos in the future? Or start matches? Or win lotteries? And for those of you, I present pure naked raw randomness--- quantum mechanics.

Meet true randomness

Quantum mechanics is a theory that deals with the description of nature at the most fundamental level. This is the level where we deal with the building blocks of matter and energy, atoms, molecules, electrons, photons, etc. At this level, nature behaves very differently from how it appears in our everyday life, as we will shortly see.

A quantum coin

Think again of the toss of a coin. But this time, it is a quantum coin, for example, the spin of an electron. Electrons are part of the building blocks of matter. These are the genie we have released from the magic teapot with the difference that we can make more than three wishes. Everything around you that moves makes noises and is not a baby is running on electrons. The electrons have a property called spin. The measurement of the spin of electrons is quite easy. All you have to do is to pass the electron near a wedge-shaped magnet. The magnetic field of such magnet exerts a force on the electron, and the electron is deflected in one or the other direction depending on its spin.

When the experiment to measure the spin of an electron is performed, we find that it has only two possible values. We label them as the head (spin-up) and tail (spin down), and we have got ourselves a quantum coin.

If you now toss the quantum coin, you will again get a random output, either head or tail. But the difference from the classical (the one we discussed earlier) is that the indeterminacy is not due to any lack of information. We know everything there is to know about the electron, and still, there is no way to predict if the spin measurement will result in spin up (head) or spin down (tail).

Every event in the quantum world is a roll of dice.

This is in contrast to the classical coin, where randomness was due to a lack of information. This is the first mystery of nature at the quantum level. Nature does not allow us to know when and which fundamental interaction between the building blocks of matter and energy will take place. Every event happening at this level is a roll of dice.

In fact, this aspect of quantum mechanics has been part of a lively debate since the beginning of the theory. Many people, including Albert Einstein, were not happy with the indeterministic description of events at the quantum level. You must have heard his famous quote, “God does not play dice”. He believed that the theory was incomplete and likely missing some hidden variables that would restore the classical world, like determinism in the quantum world, when added to the description.

However, countless experiments in the last 100 years have ruled out the possibility of these hidden variable theories. And our best understanding of nature at the quantum level is the one provided by quantum mechanics, which in principle does not allow us to predict the outcome of the toss of a quantum coin.

The key point up to this point is that for a classical random process, the information is present but may not be accessible, but the quantum process is inherently random. There is no missing information.

Armed with this understanding of random processes in the classical and quantum worlds, we are ready to explore the really big questions in the biological world. First, you can appreciate that the free will absent in the deterministic world of classical laws can be restored thanks to the indeterminism in the quantum world. The only thing we have to explore is to look for quantum signatures in the brain's functioning. Many people have suggested this before, but present-day technology promises experimental verification. We might soon hear fantastic news from people doing quantum biology.

Design in disguise?

Then there is this other question that I wish to talk about. Consider life. There are two dominant theories regarding the emergence of life on this planet. Either we are part of some intelligent design, or life emerged on the planet as an accident, and through random mutations, it evolved into all the life forms we witness today (and sadly, the ones we have eradicated from the planet). Science naturally favors the second view. But most of the people who favor the scientific view do not realize that there is still the possibility of the design in their worldview. This is because we still have to determine if the processes causing mutation in a genome are governed by classical or quantum laws.

If classical laws can satisfactorily model these mutations, then these are not random. These are deterministic processes for which the information, aka design, was already present.

Whether someone had that information (The almighty God?) or not is a separate question and can be subjectively answered. What can be objectively ascertained is that a design was available. This is a unique perspective on the natural selection vs. intelligent design debate that a physicist offers. More research in quantum biology and exploration of quantum signatures in genetic mutations will tell if we are part of a design or result of truly random accidents.

Quantum biology will reveal if we are designed.

Lastly, I wish to propose an experiment to explore the thought processes as I promised. With some patience and a lot of courage, you can easily do this experiment at home. Take a piece of paper and write a few random numbers on it. Fold the paper and put it in a box. Put the box aside. Now, wait for a couple of weeks. Meanwhile, do not try to recall the numbers you have written. Obviously, do not open the box. After a couple of weeks, take another piece of paper, again write a few random numbers on it, and put it in the same box. Again wait for a couple of weeks and repeat. Over an extended period of time (say a year or six months), you would have a lot of folded papers in the box.

Now open the box and look at all the random numbers you have written over time. Are they all random? Are there some favorite random numbers? Are there patterns? Is there a design?