Italian theoretical physicist Carlo Rovelli is telling a packed classroom of 15- and 16-year-olds that science is about not believing what your teachers tell you.
While it might seem like a counter-intuitive stance, it’s all part of today’s lesson.
Rovelli, the author of the best-seller Seven Brief Lessons in Physics, has come to Sydenham School, a girls’ comprehensive in south-east London, to open the eyes of students to a world of physics beyond their classroom walls.
With its clear elucidation of complex physics, Seven Brief Lessons tells the story of our universe in fewer than 80 pages. More than half a million copies of the book have been sold in 41 languages worldwide.
Surely Rovelli deserves the title “world’s most inspiring physics teacher”? For the man himself, there is no question that it is teachers, not authors, who are responsible for bringing the subject alive.
“What matters is not what you learn, you can learn the same thing reading a book, but rather it is about seeing a real person talking about it and getting excited. Teaching in my opinion is not an intellectual thing, it’s an emotional thing.
“If it was an intellectual thing, you could replace teachers with books,” he says.
The pupils and teachers are certainly excited to have him here; Sydenham was one of 141 schools that applied to have Rovelli visit ahead of the publication of his new work, Reality is Not What it Seems: the Journey to Quantum Gravity.
Jason Ronson, head of physics at the school, says: “To have someone so well-known in the field who is working on the next big discovery is a real opportunity.”
Ronson originally planned for only the school’s 15 physics A-level students to take part, but after being swamped with requests from girls doing their GCSEs, he decided to let them attend, too.
Given that the number of students taking A-level physics is falling (down 2.7% since last year, with girls, in particular, opting out of the subject), it’s heartening to see so many students filing into the class.
Before he begins, Rovelli asks all 35 students to introduce themselves and explain what they hope to study in the future.
The result clearly gladdens Rovelli’s scientist heart, with everything from physics, astrophysics and research mathematics among the subjects mentioned, and engineering the most popular.
Introductions over, Rovelli takes the students back 26 centuries to the time of the Greek philosopher Anaximander, who dared to question his teacher’s assumption that the sky was up and the earth down. Instead, he suggested the sky was all around us.
“How could he prove this?” Rovelli asks and a few hands are raised tentatively.
One student hits upon the idea that the sun rising in the east and setting in the west day after day could prove his theory. She’s on the right track and to further help the students visualise the idea, Rovelli leaves the classroom from one door and emerges soon afterwards from another, turning himself into the setting sun.
He draws the first half of the lesson to an end with perhaps the most important piece of advice for any budding scientist: advances in science inevitably mean accepting that current thinking may turn out to be incorrect.
“It took a couple of centuries for people to be convinced by Anaximander’s theory,” says Rovelli. “So what you learn at school might in fact be wrong.”
For the second part of his lesson, Rovelli turns to another revolutionary, Albert Einstein.
“He did a similar change in the way we think about the world as Anaximander. He took something that seemed universal and fixed, and showed that it wasn’t.
“We have this idea that the present is the same for everyone.”
Turning to one of the students on the front bench, he asks: “Do you see me now?”
The student duly nods. Wrong.
Rovelli explains how light takes nanoseconds to reach our eyes, so the image of him she is seeing is actually from the past.
“You see me from a nanosecond earlier,” he says. “We don’t see just the present, but something in the past. And the more something is far away, the more I see it in the past.”
Addressing the students, Rovelli employs the same poetic expressions from his books.
The effect is that physics feels less intimidating and more engaging. At the end of the class, the students surround Rovelli and bombard him with more questions about black holes, the Big Bang, gravitational waves …
GCSE students Abisha Arulrajah, 15, and Rebecca Ranjit, 16, are smiling. “You don’t get that opportunity normally,” says Abisha. “We all want to pursue physics – it was really insightful about what we can do.”
“We feel so lucky,” says Rebecca. “It would be such a good way to get a younger generation interested in physics if everyone could have this class.”
Later, Rovelli appears equally inspired by the experience.
“I was surprised by how they already know what they want to be,” he says. “I was also surprised by how clear- minded and knowledgeable they are.”
So what is the key to making sure more students engage with the world of physics?
“There’s beauty in mathematics, but you need a good teacher to show it and drive kids to open their worlds,” he says.
“Science is a continuous process of rethinking what we know in order to try to get a bigger picture. So if you want to communicate the beauty of a subject, you have to do it in person, and you have to remember that what you are really communicating is passion.” – The Daily Telegraph