Is the world flat?
That question was posed by popular rap musician B.o.B. on his Twitter account this past week, prompting angry, but comical video and rap responses by popular science communicator Neil deGrasse Tyson and his musician nephew.
What do we really know?
A few thousand years ago, Greek philosophers and Phoenician explorers began to cast doubt on the flat-earth model. They noted differences in star visibility and the sun’s trajectory that depended on the observer’s location, leading them to propose the earth was a sphere. Convinced by this data, as well as the roundness of earth’s shadow cast on the moon during a lunar eclipse, the Greek astronomer Eratosthenes went a step further to estimate the earth’s circumference in 240 BCE. Using trigonometry and shadows cast during the solstice, he came to within a few percent of the actual value. Not bad.
Evidence backing the round-earth model grew through time and was sufficient five centuries ago to convince sailors they would not fall off earth’s edges. Magellan was the first we know of to circumnavigate the globe and to live to tell about it. Even more convincing were the famous earthrise photos sent down from lunar orbit a few hundred years later. The evidence is overwhelming. So, what’s up with B.o.B.?
Yesterday evening, I had the privilege to discuss the science of the Large Hadron Collider at CERN with a group of 13 and 14 year-olds from Seward, Alaska, USA. They connected via the ATLAS Virtual Visit system to see the experiment and to ask questions about our research. As usual, there were a lot of excellent questions, and fellow CMS physicist, Dave Barney, and I did our best to answer them all. Then we got to:
“How do you understand things you can’t see?”
Only youth can ask a question so profound.
This started me thinking about our friend B.o.B., and it occurred to me that his skepticism is not so different from that of the student nor even of the scientists at CERN who hunted for the Higgs boson.
More than fifty years ago, an idea was formed by a group of theorists, including François Englert, Robert Brout, and Peter Higgs, essentially describing how fundamental particles attain mass. The proposed mechanism requires the existence of a pervasive, non-directional (we call it scalar) force field and its associated particle, now known as the Higgs boson. It became central to a new theory, called the Standard Model, used by physicists to describe the fundamental particles that make up matter and the forces that act upon them.
The Standard Model, much like the round-earth model, proved itself over time. Just as sailors bet their lives that the earth was a sphere before seeing photos from space, physicists included the Higgs field in their theory and were able to make accurate predictions of the existence (and even the mass) of new particles before seeing images of the Higgs boson. But, we still asked:
Does the Higgs boson exist?
Yes, the empirical evidence was convincing, but just like Magellan, the astronauts, and B.o.B., we scientists wanted our photos. These finally came in 2012, in the form of high-energy proton collisions in the ATLAS and CMS detectors at CERN. Yes, there is something reassuring in seeing it with our own eyes (or detectors).
So, what’s the problem with B.o.B.? If scientists, explorers, and students have the right to be skeptical, why not a musician?
I don’t think Neil deGrasse Tyson is complaining that B.o.B. posed a question. Skepticism is key to the scientific process and questions should be asked. It is far better to ask questions than it is to blindly believe the authoritative figures who present “facts”. If you have doubts, by all means, ask!
But, B.o.B. went further. He presented a theory (in this case, a very old one) as fact. And he did this without any serious evidence to back it up. This is irresponsible for anyone, but especially for someone who is seen as an authoritative figure by his fans, and moreover for someone who has the means and ability to know better.
We can take comfort in the fact that science is based on uncovering the truth and that truth ultimately reveals itself. But human progress depends on our ability to build upon well-established bricks of knowledge. Sure, we should check the solidity of those bricks from time to time, but let’s not waste effort trying to break them for no good reason.
As a physicist, I am often challenged by friends and family to explain the relevance of our work. So, when the opportunity came last fall to speak at TEDxTUM in Munich, I happily responded to that very question with a simple answer: We have no choice. Human survival depends on basic research. Without our drive to explore and to understand the world, our species would not still be here. We would have starved, been eaten, or died of disease, a long time ago. Hence the threat of B.o.B.
And B.o.B. is not alone.
Powerful people who would like to be world leaders are acting similarly or worse, attacking evidence-based science for the sake of political gain. And while a flat-earth conspiracy might be innocuous or even silly, those who deny important measurements, such as those of climate change, threaten our survival much more directly.
So, when scientists react to B.o.B. with words, images, or even song, they are not just defending their turf, they are expressing primal instincts. They are defending our species. And when individuals like B.o.B. threaten human survival, I suggest they watch their back. They might just get pushed off the edge of the earth.
A question of survival: Why we hunted the Higgs. (Video: TEDxTUM)