String Theory For Dummies. Andrew Zimmerman Jones

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Chapter 4

      Putting String Theory in Context: Understanding the Method of Science

      IN THIS CHAPTER

      String theory is at the cutting edge of science. It’s a mathematical theory of nature that, at present, makes few predictions that are directly testable by empirical experiments. This brings up the question of what it takes for a theory to be scientific.

      In this chapter, we look a bit more closely at the methods scientists use to investigate nature’s structure. We explore how scientists perform science and some of the ways their work is viewed. We certainly don’t solve any big, philosophical issues in this chapter, but our goal is to make it clear that scientists have differing views about how the nature of science is supposed to work. Although we could write volumes on the evolution of scientific thought throughout the ages, we touch on these topics in just enough detail to help you understand some of the arguments in favor of and against string theory.

Exploring the Practice of Science

      Before you can figure out whether string theory is scientific, you have to ask, “What is science?”

      Science is the methodical practice of trying to understand and predict the consequences of natural phenomena. This is done through two distinct but closely related means: theory and experiment.

      Not all science is created equal. Some science is performed with diagrams and mathematical equations. Other science is performed with costly experimental apparatus. Still other forms of science, while also costly, involve observing distant galaxies for clues to the mystery of the universe.

      String theory has spent more than 40 years focusing on the theory side of the scientific equation and, sadly, is relatively lacking on the experimental side, as critics never hesitate to point out. Ideally, the theories developed would eventually be validated by experimental evidence. (See the later sections “The need for experimental falsifiability” and “The foundation of theory is mathematics” for more on the necessity of experimentation.)

      The myth of the scientific method

      In school, many of us were taught that science follows nice, simple rules called the scientific method. These rules are a classical model of scientific investigation based on principles of reductionism and inductive logic. In other words, you take observations, break them down (the reductionism part), and use them to create generalized laws (the inductive logic part). String theory’s history certainly doesn’t follow this simple model.

      The steps of the scientific method students are taught actually change a bit depending on the textbook schools use in a given year, though they generally have mostly common elements. Frequently, they are delineated as a set of bullet points:

In a way, this scientific method is a myth. You may earn a physics degree from a top college without once being asked a question about the scientific method in a physics course. (Though it may come up if you dabble a bit more in the philosophy of science or similar courses.)

      Turns out, there’s no single scientific method that all scientists follow. Scientists don’t look at a list and think, “Well, I’ve observed my phenomenon for the day. Time to formulate my hypothesis.” Instead, science is a dynamic activity that involves a continuous, active analysis of the world. It’s an interplay between the world we observe and the world we conceptualize. Science is a translation between observations, experimental evidence, and the hypotheses and theoretical frameworks that are built to explain and expand on those observations.

      Still, the basic ideas of the scientific method do tend to hold. They aren’t so much hard-and-fast rules, but they’re guiding principles that can be combined in different ways depending on what’s being studied.

      One of the best situations for a scientist to be in is to observe a pattern or trend in phenomena, and then use that to make a precise prediction about some other phenomenon that hasn’t yet been observed. This provides the basis for a new experiment or observation that, if it matches the prediction, provides an excellent foundation for thinking the line of reasoning that led to the prediction was probably СКАЧАТЬ