arab mathematicians

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Hundreds of years before solar viewing glasses were readily available, scientists and casual spectators could still enjoy these rare celestial events without frying their eyeballs. They’d use a combination of pinholes and mirrors to redirect the sun’s rays onto a screen.

It took a while to figure out how to build the so-called camera obscura. Ancient Chinese and Greek scholars puzzled over pinholes for centuries before an Arab mathematician and scientist came up with a design.

You can rig up your own version with simple household items. It’s easy. Skunk Bear’s latest video shows you how.

And remember, never look directly at the sun without appropriate eye protection.

Make Your Own Eclipse Viewer

Video: NPR’s Skunk Bear

anonymous asked:

Islam is backwards and needs to be removed. Muslims have never contributed anything to the progression of society.

I’m just going to leave this for you…

“… There was once a civilization that was the greatest in the world.

It was able to create a continental super-state that stretched from ocean to ocean, and from northern climes to tropics and deserts. Within its dominion lived hundreds of millions of people, of different creeds and ethnic origins.

One of its languages became the universal language of much of the world, the bridge between the peoples of a hundred lands. Its armies were made up of people of many nationalities, and its military protection allowed a degree of peace and prosperity that had never been known. The reach of this civilization’s commerce extended from Latin America to China, and everywhere in between.

And this civilization was driven more than anything, by invention. Its architects designed buildings that defied gravity. Its mathematicians created the algebra and algorithms that would enable the building of computers, and the creation of encryption. Its doctors examined the human body, and found new cures for disease. Its astronomers looked into the heavens, named the stars, and paved the way for space travel and exploration.

Its writers created thousands of stories. Stories of courage, romance and magic. Its poets wrote of love, when others before them were too steeped in fear to think of such things.

When other nations were afraid of ideas, this civilization thrived on them, and kept them alive. When censors threatened to wipe out knowledge from past civilizations, this civilization kept the knowledge alive, and passed it on to others.

While modern Western civilization shares many of these traits, the civilization I’m talking about was the Islamic world from the year 800 to 1600, which included the Ottoman Empire and the courts of Baghdad, Damascus and Cairo, and enlightened rulers like Suleiman the Magnificent.

Although we are often unaware of our indebtedness to this other civilization, its gifts are very much a part of our heritage. The technology industry would not exist without the contributions of Arab mathematicians… ”

- CARLY FIORINA, CEO of Hewlett Packard 1999-2005

npr.org
Make Your Own Eclipse Viewer
No eclipse glasses? No problem. Make your own solar viewer; (almost) no tools required.

Hundreds of years before solar viewing glasses were readily available, scientists and casual spectators could still enjoy these rare celestial events without frying their eyeballs. They’d use a combination of pinholes and mirrors to redirect the sun’s rays onto a screen.

It took a while to figure out how to build the so-called camera obscura. Ancient Chinese and Greek scholars puzzled over pinholes for centuries before an Arab mathematician and scientist came up with a design.

You can rig up your own version with simple household items. It’s easy. Skunk Bear’s latest video shows you how.

And remember, never look directly at the sun without appropriate eye protection.

“Zero” and “Cipher”

I’ve been looking for some more non-Indo-European-origin words, but unfortunately there are not very many instances where a non-IE word has been borrowed multiple times.  These two words are one such case, however.

The word zero derives from Italian zero, via French, from the Medieval Latin zephirum, a borrowing from Arabic صِفْر  ṣifr “empty”, the zero representing an blank in place-notation, a relatively recent concept introduced to Europe by Arabic mathematicians, and originally developed in India.

“Cipher” comes from the same Arabic form, through Old French cyfre, first appearing in the late 14th century.  It originally meant “zero”, but soon developed a more generic meaning of “Arabic numeral”.  Around the 1520s the sense of “encoded message” developed from the use of numbers to replace letters in early ciphers.

Western understanding of Arab history ignores Arabic math and science, including algorithmic reasoning, derived from the name of the ninth-century Arab mathematician Al-Khwarizmi (from whose book Al-Jabr wa al-Muqabalah the term algebra is derived)
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