2013 Physics Nobel

This time the pundits were right. The 2013 Nobel Prize in Physics was indeed awarded to the discovery of the Higgs boson. Peter Higgs and François Englert shared the prize for suggesting the mechanism that gives subatomic particles their mass.

The Higgs boson is a key part of the Standard Model, which is by far the best theory we have to explain how the universe works at the basic level. If the Higgs boson were not to exist, physicists would have had to go back to the drawing board.

The easiest way to understand the importance of the Higgs boson is to go back to the beginning of the universe. After the Big Bang, for a short time, all particles were massless. But soon after, when the temperature fell below a trillion degrees, the Higgs field switched on. Some particles interacting with this field slowed down and others did not. Those that did such as protons and neutrons gained mass, while others like photons and gluons remained massless. Only when this happened did matter, as we know it now, come to existence in the form of atoms.

This is what Englert and Higgs suggested independently. But others at the time were involved too. In 1964, six physicists came up with similar ideas. First was Englert at the Université Libre de Bruxelles who did it with Robert Brout. Then Higgs at the University of Edinburgh did it on his own. And finally it was a group of three researchers from Imperial College – Thomas Kibble, Gerald Guralnik and Carl Hagen.

These others, many lament, deserved credit too. That though would not have been possible. “It is no surprise that the Swedish Academy felt unable to include us, constrained as they are by a self-imposed rule that the Prize cannot be shared by more than three people,” Kibble said of him and his colleagues. Another candidate would have been Robert Brout, Englert’s colleague, were he still alive.

Still others decried the prize-awarding committee’s exclusion of experimentalists who proved the existence of the Higgs boson. The Large Hadron Collider (LHC) outside Geneva, where these experiments were conducted by the Atlas and CMS teams, was acknowledged in the official citation, but the rules of the prize restrict it to be given only to individuals.

Jon Butterworth of University College London, who was involved in the Higgs experiments at the LHC, wrote:

The discovery of a Higgs boson, showing that the theoretical ideas are manifested in the real world, was thanks to the work of many thousands. There are 3,000 or so people on Atlas, a similar number on CMS, and hundreds who worked on the LHC.

Paul Newman at the University of Birmingham, who is also involved in work at the LHC, said, “At first sight, the Higgs mechanism is a very strange idea.” So it is fitting that, 50 years after the theory was suggested, it took the world’s biggest experiment, thousands of scientists and many billions of pounds to prove the existence of the Higgs boson and thus the Higgs mechanism.

However, the repeated delays in this morning’s announcement of the prize, as the committee debated over who to give the prize to, were a sign that the most-deserved prize will also remain one of the most controversial ones.The Conversation

First published on The Conversation.

Image credit: CERN

2013 Medicine Nobel

The 2013 Nobel Prize in Medicine has been awarded to Thomas Südhof, James Rothman and Randy Schekman for their discoveries of how the transport mechanism in cells works.

Cells are the basic units of life. Each of the billions of cells that make up the human body are packed with machinery to help them perform their special roles. Brain cells (neurons), for instance, need to produce and release neurotransmitters to pass important signals to other brain cells. Other key chemicals such as enzymes and hormones also need to be similarly moved.

Before the work of these pioneering scientists, others had discovered that tiny fat globules called vesicles that were involved in the transport system. But little was known about how these vesicles perform their job, delivering key chemicals at the right place and at the right time.

Fascinated by this problem, in the 1970s, Schekman, now at the University of California, Berkeley, worked with yeast cells to figure out the details. He used cells with defective transport machinery to reveal the genes responsible for causing the problems. These genes fell in three classes, each handling a different part of the tightly regulated transport system.

Kathryn Ayscough, a molecular biologist at the University of Sheffield, said, “I still work with yeast cells to understand how cells work. This recognition with a Nobel Prize shows how elegant studies based on simple organisms can reveal intricate details of how all cells work.”

Rothman, now at Yale University, wanted to investigate further. At the time it was believed that the tightly bound space within a cell was somehow responsible in helping each vesicle reach its particular target. But by isolating key proteins that he believed were involved in vesicle transportation, Rothman discovered that the transport system worked perfectly even in a test-tube.

It turned out that the genes identified by Schekman also coded for the proteins Rothman isolated. “Taking different approaches to explain the same phenomenon is often the best way of doing science,” Mike Cousin, a cell biologist at the University of Edinburgh said.

With the cell’s internal machinery somewhat understood, Südhof, now at Stanford University, was interested in finding out how neurotransmitters were released in such a precise manner in neurons. This carefully orchestrated transfer of neurotransmitters is the basis of how our brain functions.

He found that when electrical signals travel along a neuron, they attract calcium ions and enter the cell through temporarily activated channels. These calcium ions activate proteins on the surface of the vesicles, which forces them to fuse with the membrane to off-load their fill of neurotransmitters. Südhof’s work identified the proteins involved in the fusion process.

“Without his work, we would still be looking for the molecules responsible in the fusion process,” Cousin said. Instead, in the years since Südhof’s work was published, researchers have identified that many neurodegenerative diseases, such as Alzheimer’s, are caused by the malfunctioning of fusion proteins.

“The prize-winning work shows it often takes a long time for basic research to be recognised for its impact,” Ayscough said. The researchers set out to understand how a cell works, but their work is now being used to develop medicines for some of the most debilitating diseases.The Conversation

First published on The Conversation.

Image credit: neuroimages