Today is the anniversary of Einstein's death on April 18, 1955, in Princeton, New Jersey, and of the 1991 official opening of the Hong Kong Science Museum.

Hong Kong is the third stop on the exhibition's tour of China, which began in 2005 to celebrate 60 years of Chinese-Swiss diplomatic relations. The exhibition attracted 400,000 visitors in Beijing and Guangzhou, and may go on to other Chinese cities.

The Hong Kong exhibition is the largest to date, with displays added to explain the scientific achievements of the 1921 Nobel physics laureate, such as his theory of relativity.

Regula Wyss, curator of the Berne museum, originally wanted to bring the entire Berne display to Hong Kong, but a few elements could not be transported for technical reasons.

Visitors will still get a full picture of Einstein's life by viewing many of his original documents. They include a Swiss passport he got in 1923, which cost the Berne museum about 100,000 Swiss francs (HK$870,000) - the most expensive item in the collection.

Several weeks ago, Einstein's relatives gave Wyss a letter he wrote to his son, Hans Albert Einstein. 'It's very interesting because Einstein instructed his son how to deal with his marriage issues, and it was written several years after Einstein's divorce from [first wife] Mileva Mirac,' Wyss said. The letter will be on display.

The programmes on offer include six public lectures by world-famous scholars, including one by the 1991 Swiss Nobel laureate in chemistry, Professor Richard Ernst. Visitors to the exhibition will find details about Einstein's so-called miracle year, 1905, when he published four groundbreaking papers - on the photoelectric effect, Brownian motion, special relativity and the equivalence of matter and energy - which catapulted him to the notice of academic world.

That achievement was all the more notable because Einstein was holding down a regular, 48-hours-a-week job at a patent office, Ott said. 'But in a way, that might have been a good thing,' Ott said. 'He might not have been so successful had he not been a patent officer, because he couldn't find an academic job and was hopeless. That job gave him academic freedom because no academics were above him. I think, in retrospect, he profited from it.'

Einstein's work was reflected in our daily lives, said Dr Gary Shiu, a professor of physics at the University of Wisconsin-Madison and visiting fellow at the Institute of Advanced Study at the Hong Kong University of Science and Technology.

Einstein's theories of relativity had been critical in the development of many technologies such as GPS and medical accelerators, he said. GPS relies on precisely timed signals travelling at the speed of light between devices on the ground, like smartphones, and satellites orbiting thousands of kilometres above earth.

At those distances and speeds, said Shiu, a timing error of one microsecond translates into a distance error of 11 kilometres. Without using Einstein's theories of relativity, GPS calculations would be off by roughly 38 microseconds over the course of a day, making GPS effectively useless.

Medical accelerators, used in radiation therapy for cancer treatment, also rely on relativity. They use beams of electrons travelling close to the speed of light to target tumours with radiation while avoiding excessive damage to healthy surrounding cells. Medical accelerators have been in use for more than 50 years.

Shiu said he hoped that by grounding Einstein's work in its day-to-day applications, the exhibition would show people the value of fundamental scientific research.