One of the greatest triumphs of the natural sciences is Einstein’s theory of general relativity. Combining spectacular creativity, brilliant reasoning, bold conjectures and dramatic experimental confirmation, it seems to be all that science should be. But what if Einstein was wrong? The history of science is full of theories that once seemed ‘right’, but which we now know are ‘wrong’. Famously, the Sun does not revolve around the Earth, atoms are not the smallest particles, and Mars has no canals on it. Some of today’s science seems so outrageous that surely it is just a matter of time before today’s beliefs are superseded and discarded. So why shouldn’t Einstein be wrong?
Well, most scientists believe that eventually Einstein will be proven ‘not right’. But ‘not right’ does not mean ‘wrong’, as we realized when we considered the way that models work in science. This can lead to confusion because we tend to think of science as black and white. We can argue about shades of grey in the arts, or perhaps the social sciences, but we tend to think of ‘truth’ and ‘certainty’ in physics. However, this may be incorrect. Dividing the scientists into the ‘bad guys’ (who tried hard, but got it wrong) and the ‘good guys’ (who got it right) is a little too simple.
by Nicholas Alchin, Carolyn P. Henly
Chapter 3 The natural sciences
‘Right’, ‘wrong’ and scientific ‘truth’
One of the greatest triumphs of the natural sciences is Einstein’s theory of general relativity. Combining spectacular creativity, brilliant reasoning, bold conjectures and dramatic experimental confirmation, it seems to be all that science should be. But what if Einstein was wrong? The history of science is full of theories that once seemed ‘right’, but which we now know are ‘wrong’. Famously, the Sun does not revolve around the Earth, atoms are not the smallest particles, and Mars has no canals on it. Some of today’s science seems so outrageous (chaos theory tells us that a butterfly flapping its wings can cause a hurricane on the other side of the world!) that surely it is just a matter of time before today’s beliefs are superseded and discarded. So why shouldn’t Einstein be wrong?
Well, most scientists believe that eventually Einstein will be proven ‘not right’. But ‘not right’ does not mean ‘wrong’, as we realized when we considered the way that models work in science. This can lead to confusion because we tend to think of science as black and white. We can argue about shades of grey in the arts, or perhaps the social sciences, but we tend to think of ‘truth’ and ‘certainty’ in physics. However, this may be incorrect. Dividing the scientists into the ‘bad guys’ (who tried hard, but got it wrong) and the ‘good guys’ (who got it right) is a little too simple.
Of course, Einstein is the archetypal ‘good guy’. He managed to solve problems that even the great Newton got wrong. Strange, then, that Newton’s ‘wrong’ ideas are still used by NASA for satellites and space shuttles. Why do all our daily experiences (apples falling and the like) obey his rules? Why does the moon still orbit according to Newton’s formulas? Newton’s laws work. How can they be wrong?
The answer to the apparent contradiction between Newton and Einstein is surprisingly simple. Einstein generally agrees with Newton; in fact, the only point of disagreement is over issues that Newton never considered (such as speeds extremely close to the speed of light, or near objects with intense gravitational fields). That is, Einstein built on Newton’s theories, added to them and took them to new levels of complexity and sophistication. If Newton had been completely wrong, Einstein could not have been right. To say that Einstein ‘disproved’ Newton is to miss the point of the process – without Newton, there could not have been Einstein.
‘Right’ and ‘wrong’ therefore may not be useful ways to describe scientific theories. Physicist David Bohm puts it well: ‘The notion of absolute truth is shown to be in poor correspondence with the actual development of science. Scientific truths are better regarded as relationships holding in some limited domain.’
New ideas rarely mean abandoning old ideas completely. Rather they stretch, expand and build upon old ideas. Scientists used to argue about whether light was a wave or a particle. It turns out (so we now think) that it is both. The new theory of light does not disprove either old theory, rather it unites and enlarges them. Our model has expanded to explain more data.
This simple point is often lost in the very human desire to categorize ideas as ‘right’ or ‘wrong’. We like clarity and easy answers and we tend to shy away from more complex notions if we can. This means that we sometimes see a ‘scientific revolution’ when there was really a slow evolution of scientific theory. Physicist Hendrik Casimir writes: ‘The gradual evolution of new theories will be regarded as revolutions by those who, believing in the unrestricted validity of a physical theory, make it the backbone of a whole philosophy.’
‘Right’ ideas are ideas that lead to other ideas and that seem to make deep and unexpected connections to other areas of knowledge. Sometimes they lead to a new explanation of a familiar phenomenon. ‘Wrong’ ideas, by contrast, do not lead anywhere.