Scientist of the day - Brahmagupta

Brahmagupta was an Ancient Indian astronomer and mathematician, who lived from 597 AD to 668 AD. He was born in the city of Bhinmal in Northwest India. His father, whose name was Jisnugupta, was an astrologer.

Although Brahmagupta thought of himself as an astronomer who did some mathematics, he is now mainly remembered for his contributions to mathematics.

Many of his important discoveries were written as poetry rather than as mathematical equations! Nevertheless, truth is truth, regardless of how it may be written.

Quick Guide to Brahmagupta

• was the director of the astronomical observatory of Ujjain, the center of Ancient Indian mathematical astronomy.

• wrote four books about astronomy and mathematics, the most famous of which is Brahma-sphuta-siddhanta ( Brahma’s Correct System of Astronomy, or The Opening of the Universe.)

• wrote that solving mathematical problems was something he did for pleasure.

• was the first person in history to see zero as a number with its own properties.

• defined zero as the number you get when you subtract a number from itself. Identifying zero as a number whose properties needed to be defined was vital for the future of mathematics and science.

• said that zero divided by any other number is zero.

• said that dividing zero by zero produces zero. (Although, this seems reasonable, Brahmagupta actually got this one wrong. Mathematicians have now shown that zero divided by zero is undefined – it has no meaning. There really is no answer to zero divided by zero.)

• was the first person to discover the formula for solving quadratic equations.

• wrote that pi, the ratio of a circle’s circumference to its diameter, could usually be taken to be 3, but if accuracy were needed, then the square-root of 10 (this equals 3.162…) should be used. This is about 0.66 percent higher than the true value of pi.

• indicated that Earth was nearer the moon than the sun

• incorrectly said that Earth did not spin and that Earth did not orbit the sun. This, however, may have been for reasons of self-preservation. Opposing the Brahmins’ religious myths of the time would have been dangerous.

• produced a formula to find the area of any four-sided shape whose corners touch the inside of a circle. This actually simplifies to Heron’s formula for triangles.

• wrote that the length of a year was 365 days 6 hours 12 minutes 9 seconds.

• calculated that Earth was a sphere of circumference around 36,000 km (22,500 miles).

Brahmagupta established rules for working with positive and negative numbers, such as:

• adding two negative numbers together always results in a negative number.

• subtracting a negative number from a positive number is the same as adding the two numbers.

• multiplying two negative numbers together is the same as multiplying two positive numbers.

• dividing a positive number by a negative, or a negative number by a positive results in a negative number.

World Tuberculosis Day - 2015

World Tuberculosis Day - 2015

World TB Day, falling on 24th March each year, is designed to build public awareness that tuberculosis today remains an epidemic in much of the world, causing the deaths of nearly one-and-a-half million people each year, mostly in developing countries. It commemorates the day in 1882 when Dr Robert Koch astounded the scientific community by announcing that he had discovered the cause of tuberculosis, the TB bacillus. At the time of Koch's announcement in Berlin, TB was raging through Europe and the Americas, causing the death of one out of every seven people. Koch's discovery opened the way towards diagnosing and curing TB.

Background

On World TB Day, 24 March, WHO is calling for new commitments and new action in the global fight against tuberculosis – one of the world’s top infectious killers.

There has been tremendous progress in recent years, and the world is on track to meet the Millennium Development Goal of reversing the spread of TB by 2015. But this is not enough. In 2013, 9 million people fell ill with TB and 1.5 million died.

WHO strategy to end the global TB epidemic

Last May, at the World Health Assembly, governments agreed on ambitious new 20-year (2016-2035) strategy to end the global TB epidemic.

WHO’s End TB Strategy envisions a world free of TB with zero deaths, disease and suffering. It sets targets and outlines actions for governments and partners to provide patient-centred care, pursue policies and systems that enable prevention and care, and drive research and innovations needed to end the epidemic and eliminate TB.

On World TB Day 2015, WHO calls on governments, affected communities, civil society organizations, health-care providers, and international partners to join the drive to roll out this strategy and to reach, treat and cure all those who are ill today.

24 March 2015 - the day to change gear and speed up global efforts to end TB altogether.