Tag Archives: Bohr

Copenhagen: at the nexus of drama, science and history

“History is what you remember as having happened, not what actually happened.” It was this thought, shared by Michael Frayn in a recent discussion with the Director of the Science Museum, that that lies at the heart of Copenhagen, the most famous work of the playwright and novelist.

Michael Frayn has a long-held interest in philosophy and the sciences, notably in his book The Human Touch: Our Part in the Creation of the Universe. However, he is best known for his Tony-award winning play, which was staged at the National Theatre in London and later on Broadway in New York.

Copenhagen is an enduring example of how the history of science can inform dramatic work, and vividly demonstrates the power of drama to explore history, bringing scholarly discussions to the attention of a wide audience.

Ian Blatchford, Director of the Science Museum, in conversation with Michael Frayn

Ian Blatchford, Director of the Science Museum (right), in conversation with playwright Michael Frayn

The play examines the uncertainties surrounding the 1941 meeting between two Nobel prize winning physicists in German-occupied Copenhagen at the height of World War II.

Physicist Werner Heisenberg, head of the German nuclear energy project, and his Danish counterpart Niels Bohr, who later worked on the Manhattan Project, discussed the possibility of building an atomic bomb.

There was no accurate record of what was said at the meeting, and there are conflicting recollections made years later in unsent letters and transcripts from Heisenberg’s internment shortly after the war at Farm Hall, a bugged house near Cambridge. As a consequence, Frayn’s dramatisation of the meeting has itself become part of the historical record.

Those listening to Michael Frayn in the audience, included his wife, the biographer Claire Tomalin, Tony award-winning director of Copenhagen, Michael Blakemore, and Niels Bohr’s great grand-daughter, Esme Dixon. Prof Jon Butterworth of University College London, science biographer Graham Farmelo, Science Museum Trustee Howard Covington, Jean M Franczyk, Director of the Museum of Science & Industry and Andrew Nahum, Principal Curator of Technology and Engineering, were also present for the fascinating discussion.

You can watch the full conversation between Michael Frayn and the Science Museum Group’s Director, Ian Blatchford, here.

A hundred years of the quantum atom

Alice Lighton, content developer for our Collider exhibition, writes about the history of quantum physics. Colider: step inside the world’s greatest experiment opens in November 2013 with a behind-the-scenes look at the famous CERN particle physics laboratory. 

A few years ago, a friend asked a question that took me somewhat by surprise. “Alice,” he said, “is quantum physics right, or is it just a theory?”

At the time I was in the midst of a physics degree, so my initial response was “I hope so!” Quantum physics matches up to experiment extraordinarily well – it is often called the most accurate theory ever. But the question, and subsequent conversation, made me realise how little many people know about the subject, despite its profound impact on modern life and the way we think about the universe.

This year is the centenary of the publication of one of the theories that laid the foundation for our understanding of matter in terms of quanta – packets of energy. According to quantum mechanics, light is not a wave, but lump of energy called photons. Max Planck came up with the idea at the end of the 19th Century, though he considered his light ‘quanta’ a useful model, rather than reality.

Niels Bohr

Niels Bohr, one of the founders of modern physics.

One hundred years ago, in 1913, the young Danish researcher Niels Bohr sent a paper to the Philosophical Magazine in London that used these quanta to solve a serious problem with theories about the atom. At the time, scientists thought the atom was like a solar systems; electrons orbit a nucleus of protons and neutrons. But anything that moves in a circle gradually slowly radiates energy, and so moves closer to the centre of orbit. Eventually, electrons should fall into the nucleus of the atom.

But they blatantly don’t, otherwise everything in the Universe would collapse, and we wouldn’t exist. Bohr proposed that electrons could only sit in discrete orbits or distances from the nucleus – and therefore when electrons change orbit transitions between orbits emit only emit energy in discrete packets (quanta), not gradually. The electrons therefore stay put in their orbits, and don’t fall into the nucleus of the atom.

A hydrogen atom is made from one electron orbiting a proton. Photo credit: flickr/Ludie Cochrane

Bohr was the first to show that packets of energy could successfully explain and predict the behaviour of atoms, the stuff that makes up you and me. His results were only approximately correct, but a big improvement of previous theories.

Generations of scientists have built on Bohr’s insight to understand and create the modern world. When my friend asked whether quantum physics worked, I pointed at his laptop. Computers, nanotechnology, and the Large Hadron Collider owe their existence to the physics that began with Bohr’s generation.

The CMS experiment at the Large Hadron Collider tries to work out the rules governing the sub-atomic world. Photo credit: CERN

Bohr’s original papers are clear and comprehensible, a beautiful read for physicists. The mathematics involves nothing more difficult than multiplication and division, yet the philosophical implications are immense. Max Planck never fully accepted quantum physics; neither did Albert Einstein, despite winning a Nobel Prize for his work on the subject.

Bohr also won a Nobel Prize for his quantum theory, but his work did not stop. He founded the Niels Bohr Institute, a centre of theoretical physics in Copenhagen, worked on the Manhattan Project developing the atomic bomb, and continued to make contributions to quantum mechanics.

And he has a lovely link to the exhibition I’m currently working on, about the Large Hadron Collider. Bohr was influential in the founding of CERN, the Geneva laboratory that is home to the LHC. If he had his way, the LHC would be in Denmark, but other scientists objected – Northern Europe was too cloudy, and had too few ski resorts, for Italian tastes.