Instead, Dirac interpreted it as antimatter and, four years later, it turned up in a real experiment.

ECONOMIST: Fundamental physics

The existence of anti-matter was first suggested by the theoretical physicist Paul Dirac in the 1930s.

BBC: The problem with anti-matter

Monopoles were first predicted in 1931 by Paul Dirac, the man who also predicted antimatter.

ECONOMIST: Magnetic monopoles: Absence of evidence | The

Theoretical physicist Paul Dirac, scientist Dorothy Hodgkin and science lecturer Richard Feynman have also been honoured with road names.

BBC: Building at Science Park

In his equations Dirac strove for an orderly beauty above all else, believing that nature prefers elegance and simplicity.

ECONOMIST: Modern scientists: Physical presence | The

Sudarshan will be giving the 2010 Dirac Medal lecture at ICTP in Italy.

UNESCO: Science Policy and Capacity-Building

But, tantalisingly, Dirac's theory says nothing about the masses of his particular monopoles.

ECONOMIST: Magnetic monopoles: Absence of evidence | The

The reason this is important is that Dirac's equation is misleading.

ECONOMIST: Fundamental physics

On Wednesday 10 November 2010 to mark the celebration of World Science Day for Peace and Development and the 25th anniversary of Dirac Medal lecture, Professor E.

UNESCO: Science Policy and Capacity-Building

Paul Dirac was a shy, lonely character, who almost refused the 1933 Nobel prize for his famous equation because he feared it would incite too much publicity.

ECONOMIST: Modern scientists: Physical presence | The

So when, in 1928, a British physicist called Paul Dirac solved such an equation relating to the electron, the fact that one answer described the opposite of that particle might have been brushed aside as a curiosity.

ECONOMIST: Fundamental physics