Failure is an option!

 

[I wrote this over lockdown and forgot to post it but here it is now!]

Failure is an option!

It is well established that social media is not an accurate reflection of the ‘real world’. Photos are retouched, successes broadcast loud and proud whilst failures are kept quiet. However, with the recent pandemic, online platforms have become an increasingly significant way to connect with others and escape the drudgery of lockdown; it has become harder to separate online life and offline life.

Since failure is rarely posted online (or talked about in general), when you experience it, it can feel like you are alone. It can feel embarrassing and alienating. But I am here to tell you that failure is an option, sometimes even the best possible outcome! Let me tell you about the world’s most famous ‘failed’ experiment.

For millennia, curious humans have been asking the question ‘What is light?’. Some supposed that light was made up of tiny particles. I like to picture it like pixie dust. Others supposed that light was a wave. If it were a wave, it would make sense that it would be a wave travelling through something: a medium. Sound waves need a medium to travel through. That is why in the vacuum of space, no one can hear you scream! So light waves would too, right? In 1678, Christiaan Huygens called this hypothetical medium ‘luminiferous aether’.

Almost 200 years later, two distinguished physicists designed an experiment to detect this aether and prove once and for all that light is a wave. They were Albert Michelson and Edward Morley, and their experiment is known (imaginatively) as the Michelson-Morley experiment. The idea was, if the aether existed, it would flow in a continuous wind through space. As the Earth rotates on its axis and orbits the sun, the direction of the aether wind would change with respect to an experiment on the Earth’s surface. Therefore, you would expect the speed of light measured on Earth to be different in different directions. Like a fish would appear to swim slower upstream than downstream to a fisher on the riverbankThe piece of kit designed by Michelson and Morley was impressive in its simplicity. Known as an interferometer, it is essentially two long arms at right angles with mirrors at the ends and a semi-transparent mirror facing diagonally at the intersection. When light enters the interferometer, half of the light passes through the semi-transparent mirror and travels down one arm and the other half is reflected down the other arm. When it reaches the end of the arm, it is reflected back to the intersection and the two beams of light ‘interfere’, creating a pattern of bright and dark regions on a screen. It is easiest to visualise with the help of a diagram.


If  the aether existed, you would expect to see the interference pattern change over time. The recombining light beams would be travelling at different speeds, depending on their direction compared to the aether wind, and so would be different amounts ‘out of sync’. Rather than wait for the earth’s rotation to change the direction of the light beams, Michelson and Morley floated the whole apparatus in a large bath of mercury. This allowed them to smoothly rotate the experiment with just a small push!

So what changes did they see when they ran their experiment? Nothing. No change when they rotated the apparatus, no change over the course of the day as the Earth rotated. The experiment to prove the existence of the aether was an embarrassing failure.

It appeared that light travelled at the same speed in every direction. Whilst this may at first seem like a non-result, it actually had profound implications. Disproving the existence of aether was, in a way, an even bigger success than proving it. It led to a complete rethink of what light is and how it behaves, eventually leading to something you will all have heard of: Einstein’s theory of special relativity. What Michelson and Morley had unintentionally discovered is now known as ‘the constancy of the speed of light’ and is one of the fundamental principles of relativity. Einstein himself wrote “If the Michelson–Morley experiment had not brought us into serious embarrassment, no one would have regarded the relativity theory as a (halfway) redemption.” [1]

What if Michelson and Morley had been too embarrassed to publish their result? Too embarrassed to admit they had proved themselves wrong? The theory of relativity may have taken longer to gain acceptance and acclaim. Without an understanding of relativity, we would have no functioning GPS satellites. In short, without Michelson and Morley,  today’s technological landscape might look very different!

The lesson of this story is that failure is not always a bad thing. Sometimes we learn more from things ‘going wrong’ than if we succeed first time at everything we try. Failure has value, failure is important, failure is an option. So next time something doesn’t turn out as you had hoped, remember that there may be unforeseen positive consequences yet to come. And if you feel like a failure, remember: you’re in good company.


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