Hard Science

My formal education and former career were in the so-called “hard science” of physics. I also taught college physics for a brief stint, and was taken aback by how many students came to the course apprehensive—if not downright fearful—about surviving the experience. Physics, it seems, has acquired a frightful reputation. I soon took it as a challenge to demonstrate that this most basic of sciences is remarkably straightforward and even engaging. I tried to make it fascinating... with modest success at best. Within the department that I taught, there were other science classes in biology and chemistry. I don't think that their instructors dealt with students who were as intimidated as I did—and I never quite understood why.

In contrast, biology is not a “hard” science—although when put that way, the contrast makes it seem as if biology is easier... or even “soft,” whatever that means. Whatever the descriptive terms used, physics and biology are two contrasting sciences—the former is far more basic. One of the fundamental differences in the two sciences is that most researchers in the so-called hard science of physics have a pretty good idea of what things they are looking for in their research. As an example, a major effort in physics for decades now has been the so-called “grand unified theory,” that integrates the four fundamental forces of nature: gravity, electromagnetism, and the strong and weak nuclear forces. Physicists know pretty much where they are headed (to realize that unification)—the struggle is deciphering the fierce mathematics to get there. Another example: last year a huge team of physicists demonstrated the existence of the Higgs boson—a particle that had been predicted to exist for decades. Its discovery had to wait for a powerful enough machine to expose it.

Biology, however, is neither elegant nor straightforward, like physics. Biology deals with the messy living world—a domain rife with variety and unpredictable complexity. Life is the result of a long process of historical accidents—unpredictable events that have brought about species that responded well to those random historical incidents. For example, the ascendancy of mammals began about 65 million years ago, in the wake of an unlikely collision that brought a massive meteorite to impact Earth and did away with the dinosaurs. No one could have seen that impact coming. Sudden and haphazard climate changes have similarly caused many species to evolve in manners that no “grand unified theory” could ever have anticipated.

As a result, biologists are often left hanging as to why certain organisms developed the way they did. They are often forced to project back in time, surmising causal factors for the observations they make. At times these factors are discovered through a process of complex scientific sleuthing. At other times it seems as if they might never fully be understood.

Biology is a frustratingly complex and difficult science. At least it seems that way to me—having been trained in what is considered a more basic science. In recent years I have become increasingly fascinated with biology, but struggle with its complicated and manifold divisions. It seems as if I have to memorize hundreds of terms and all of their relationships, in order to get anywhere with it. I'm glad I'm not a college student sitting in a biology class—trying to understand such a difficult subject.

Digital or Analog?

Is the fundamental nature of the universe continuous or discrete? Does matter come in lumps or waves? Is the material universe intrinsically a digital or an analog thing?

It's an ancient debate that has relentlessly been waged for over two millennia in the Western world. (I can't speak for the Chinese; they may have been arguing about it for 5,000 years or so.) The pendulum periodically swings toward the discrete side, as scientists view the natural world as made up of particles: discrete elements like atoms. Then it will swing the other way for a period of time, as those who view nature as continuous will gain the upper hand. The dispute carries on today.

The ancient Greeks were among the first to draw opposing sides on the issue. Aristotle and his camp saw the world as continuous, while the atomists saw it as discrete. Long before technology advanced to the point that the existence of atoms could be demonstrated, their actuality was presciently posited by Democritus and his followers.

Look at a river. The flowing water looks continuous. No matter how much you subdivide it—down to a trickle or even a drop—it appears to the naked eye to be the same thing: a clear, unbroken liquid. So Aristotle and his buddies reasoned. And yet we moderns know that water is composed of discrete molecules of H₂O; tiny discontinuous entities. Modern chemistry shows us that the water molecule is further composed of atoms of hydrogen and oxygen—which are themselves made up of protons and electrons...just finer, discrete lumps of matter. 

But wait: we don't need to stop at these particles. Protons and electrons are made up of quarks and leptons...still finer particles. But wait again: modern particle physics knows that another way of looking at these most fundamental building blocks is that they are apparently composed of continuous energy fields. Some physicists call the newly-discovered Higgs boson a particle, some call it the Higgs field. So these most fundamental particles can also appear to be like “ripples” in continuous energy fields. 

Now we seem to be back to the analog. And so it goes: Is the universe continuous or discrete? Analog or digital? It seems to depend on how fine you look at it and your preference. The debate goes on.

Another conundrum of this type can be encountered when one considers light. Ever since Newton's time (18^th century) one scientific camp has considered light to be made up of particles (photons) and another camp views light as waves. Quantum mechanics entered the fray in the early 20^th century and added its weight to both sides of the argument. Is light particles or waves? Discrete or continuous? Well, the discomfiting thing about quantum mechanics is that the answer is never definitive. The answer always seems to be: depends; could be both. Depends on how you look at it. That's no help!

So here we are in the 21^st century—still not sure if nature, at its heart, is analog or digital. The debate rages on. Will we ever find an answer? Maybe a more pertinent query is: Are we even asking the right question?