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Physics Evolution - Text Only Version

100 AD to 1100 AD

During what was known as The Dark Ages in Europe, the Roman Empire collapsed and disease, chivalry and superstition took over in Europe. However, Chinese thought continued to develop and Islamic culture (beginning c.600) flourished, nurturing the philosophy and mathematics of the Greeks.

Hypatia, Philosopher and mathematician - Famous woman who was murdered (c. 360 AD to 415 AD)

Egyptian philosopher and mathematician born in Egypt and worked in Alexandria.

Hypatia was a thinker, who like Ptolemy, kept the tradition of Greek astronomy alive in Alexandria in the early centuries of the Christian era.

She died violently - probably because, as a pagan, she was blamed for difficulties between the authorities and Christians. She was dragged from her classroom by monks who pelted her to death in the street.

Hypatia was a well known author, inventor and letter writer. She wrote on geometry, algebra and astronomy and invented apparatus for distilling water, an instrument to measure the specific gravity of water, an astrolabe and a planisphere.

She travelled widely and corresponded with people all over the Mediterranean. Letters addressed simply to 'The Philosopher' were delivered to her and today she is regarded as science's first famous woman.

Al-Khwarizmi, Persian mathematician - We have algebra thanks to him (c. 780 to 850 AD)

Mohammed al-Khwarizmi gave us the words (and techniques of) algebra and algorithms. He was a scholar at The House of Wisdom in Baghdad and brought together ideas from Babylon, India and Greece.

Two of al-Khwarizmi's most influential books were Al-jabr wa'l Muqabalah, which gave its name to algebra, and Al-Khwarizmi on the Hindu Art of Reckoning, from which we get the word algorithm (based on his name).

He helped bring the idea of zero into mathematics; although a symbol for zero had been introduced by the Babylonians, it was Indian mathematicians who had started using it as a number in the 6th century.

Al-Razi, Doctor and philosopher - First medical user of opium (ca 841 to 926)

Persian doctor, philosopher and thinker from Rayy.

Abu Bakr al-Razi (also known as Rhazes) was born and died in Raay near Tehran.

Al-Razi worked mainly as a doctor. However, as a thinker and writer (of 184 books), he contributed to the understanding of medicine, philosophy, alchemy and chemistry.

He developed Democritus' atomic theory into something that was remarkably close to John Dalton's scheme a thousand years later. However, it was not widely adopted.

He was interested in astronomy and discovered the Andromeda galaxy.

His medical writings greatly influenced the Islamic world as well as Western Europe in the Middle Ages and he is credited with the first uses of alcohol and opium (as an anaesthetic) in medicine.

Al-Haytham, Persian astronomer and engineer - A man who pretended to be mad (c. 965 to 1040)

Abu Ali al-Haytham was born in Basra in what is now Iraq. While still in Basra, he built up a reputation as an accomplished thinker and, at some point, moved to Alexandria in Egypt.

He worked for the eccentric and dangerous Caliph, Al-Hakim and, according to one story, spent a number of years pretending to be mad to hide from him.

During this time, he wrote about optics and astronomy. His works on optics were the first since Ptolemy's nearly a thousand years earlier.

Al-Biruni, Astronomer and cartogropher - Mapped the curved world onto flat maps (973 to 1048)

Abu Arrayhan al-Biruni was born near the Aral Sea in what is now Uzbekistan. He worked on a way to project the spherical Earth onto flat maps and therefore had a great influence on the traders then travelling between the Arab and Chinese worlds.

By the age of 19, he had measured the latitude of his home town, Kath, using the maximum altitude of the Sun.

Ibn-Sina (Avicenna), Arabian physician and philosopher - Wrote 400 books, including an autobiography (981 to 1037)

Arabian physician and philosopher

Abu Ali al-Husain ibn Abdallah ibn Sina is often known by his Latin name, Avicenna. Unlike many of his contemporaries, we know quite a bit about him because he wrote an autobiography.

Ibn-Sina is best known as a physician and his book The Canon of Medicine. However, he wrote over 400 books, with 150 surviving, on philosophy. These include an encyclopedia of logic, geometry and astronomy called The Book of Healing.

Much of his work was to collect and publish existing ideas and bring them to a broader audience. However, he also made contributions to astronomy including showing that Venus is closer to the Sun than the Earth and proposing that the speed of light is finite.

Ibn Rushd, Moorish physician and philosopher - Was banished and had his books burned (1128 to 1198)

Like Anaxagoras before him and Galileo after, Ibn Rushd was a philosopher who clashed with the religious authorities - this time the Caliph.

Abu'l Waleed Ibn Rushd - also known as Averroes - was born in Cordova (Cordoba) in Spain and studied law and medicine.

His works on Aristotle brought Greek philosophy back into the mainstream and to a wider audience. He is therefore an important figure in the development of Western philosophy as well as Islamic thought.

Despite his assertion that there was no conflict between religion and philosophy, he was banished in 1194 and his philosophical books were burnt. This was on the grounds that Greek philosophy was contrary to Islam.

He was allowed to return to Morocco just before he died.

Su Song, Chinese mathematician and astronomer - Astronomical clock (c. 1050 to 1100)

Mathematician and astronomer from Bianjing (now Kaifeng in Henan)

In 1088 Su Song, the Chinese Minister of Punishments and expert in the calculation of calendars, designed and built a water driven astronomical clock.

The clock tower was over 10 metres tall and stood in the open. It had three levels that were for astronomical observations, showing the movements of the planets and, using wooden figures, struck the time of day.

It was the most advanced astronomical instrument of its day. According to contemporary records, its precision was such that it was said to have 'measured time as exactly as the sundial'.

After a number of failed attempts, historians have recently managed to build a working replica at the National Museum of Natural Science in China.

Fire arrows - Gunpowder rockets (c. 1200 AD)

Chinese alchemists had known for over a thousand years that sulphur and saltpeter were useful for starting fires. Sometime in the 8th century, they found that combining them with charcoal produced a fiery substance that they called huoyao and we call gunpowder.

At some point they realised that they could unnerve their enemies if they packed the gunpowder into bamboo tubes and launched them on an arrow - like a rocket.

Their first recorded use was in 1232 during the war with the Mongols, who produced their own rockets later and probably brought them (and gunpowder) west to Europe. Da Vinci would have been intrigued by these rockets.

Compass for navigation - The magic of metal needles (c. 200 to 1100 AD)

The Chinese had been using loadstone from early in the first millennium BC. However, it is not practical for a navigational compass because it is so bulky.

In around 200 AD, they developed compasses with iron needles. By heating the needle and letting it cool lying north-south, it becomes magnetised.

However, it wasn't until about 1100 AD that Chinese sailors used compasses for complex navigation. It is thought that Arab traders probably learned the skill from them some time in the 12th century. They then brought the practice to the Western world.