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The 13 Most Important Numbers in the Universe - James D. Stein's Cosmic Numbers

The 13 Most Important Numbers in the Universe - James D. Stein's Cosmic Numbers
In the 17th century, scientists understood three phases of matter—solids, liquids and gases (the discovery of plasma, the fourth phase of matter, lay centuries in the future). Back then, solids and liquids were much harder to work with than gases because changes in solids and liquids were difficult to measure with the equipment of the time. So many experimentalists played around with gases to try to deduce fundamental physical laws. Robert Boyle was perhaps the first great experimentalist, and was responsible for what we now consider to be the essence of experimentation: vary one or more parameter, and see how other parameters change in response. Boyle discovered the relationship between the pressure and volume of a gas, and a century later, the French scientists Jacques Charles and Joseph Gay-Lussac discovered the relationship between volume and temperature. Related:  Topics - matiereScientific Representation

Scientists Find a Population of Butterflies That Appears to Be Splitting Into Two Species Nov. 5, 2009 AUSTIN, Texas — Breaking up may actually not be hard to do, say scientists who've found a population of tropical butterflies that may be on its way to a split into two distinct species. Polymorphic mimicry in Heliconius cydno alithea in western Ecuador, where the white form (middle left) mimics the white species Heliconius sapho (top left) and the yellow form (middle right) mimics the yellow species Heliconius eleuchia (bottom right). Image: Marcus Kronforst and Krushnamegh Kunte The cause of this particular break-up? In a paper published this week in the journal Science, the researchers describe the relationship between diverging color patterns in Heliconius butterflies and the long-term divergence of populations into new and distinct species. Heliconius butterflies display incredible color pattern variation across Central and South America, with closely related species usually sporting different colors. Heliconius provides a model for a different kind of study.

The History of Encryption The History of Encryption 700 BC Scytale The Spartan military used scytales to send sensitive missives during times of battle. Both sender and recipient had a wooden rod of the exact diameter and length. To encrypt a message, the sender tightly wound a piece of leather or parchment around the stick and wrote a message on it. The unwound leather was sent to the recipient, who could only read a message once it was tightly wound around his own scytale. 1467 Alberti cipher Leon Battista Alberti invented and published the first polyalphabetic substitution cipher, changing the course of encryption forever. 1797 Jefferson wheel Invented by Thomas Jefferson while he was George Washington's secretary of state, the wheel consisted of 26 cylindrical wooden pieces threaded onto an iron spindle. 1943 Enigma machine 1961 First computer password Developed by MIT's CTSS (Compatible Time-Sharing System), when computer time was scarce, extremely expensive and limited to research institutions. 1995 "Hackers"

Vertical Farms Sprout into Reality | Dickson Despommier NEW YORK — Seven billion humans need farms that cover a land mass equal to South America, but tomorrow's farmers may need even more space to grow food for hungry mouths. Such urgency has given root to a new agricultural idea in the past few years — building vertical farms that climb toward the sky or burrow beneath the Earth. Vertical farming got a big boost from a class taught by Dickson Despommier, a microbiologist and ecologist at Columbia University, in 1999. "There are now real vertical farms," Despommier said. Vertical farms offer the vision of growing whatever people want, wherever they want. Still, many people thought vertical farms were crazy even up to three years ago, Despommier said. The most futuristic farms exist in Asian countries such as South Korea, Japan and Singapore where crowded cities and scarce land make vertical farming most appealing. Even the U.S. has begun sprouting a few vertical farms.

FAQ on Vedic Mathematics (From Georges Ifrah's The Universal History of Numbers) FAQ in Ancient Indian Mathematics If you have questions on Vedic Mathematics or related topics, don't be bashful, send them to Aryabhatta@indicethos.org. No question will be deemed too simple or obvious. Contents Answers What were the strengths of the ancient Indian Mathematicians The Indian Mathematicians of the ancient era were primarily number theorists. ax + by = 1: this is a linear Diophantine. Another field or approach which the ancients favored was algebraic geometry, where geometry was studied predominantly using algebraic equations. The use of concise mathematical symbolism (<,>,=,*,(), inf., sup., the integral sign, the derivative sign, the sigma sign etc is a relatively recent revolution in mathematics, When calculus was invented by Newton and Leibniz independently, they used different notations. Ironically it was the Indian place value notation that triggered the advance in Europe. Later texts were known as Siddhantas

What Is the Speed of Sound? | Wired Science Image: Red Bull Stratos This seems to be the most common discussion regarding the recent Red Bull Stratos Jump. Unless you have been living under a rock lately, you have probably seen the awesome jump from 128,000 feet. Here is a great summary video to get you pumped up. The official fastest free fall speed was reported as 373 m/s. What Is a Sound Wave? First, let me talk about just sound in air. What happens if you take a whole bunch of these particles and push them all at the same time? Another great example of this is the wave in a football stadium. What goes around the stadium? Actually, now I am curious. OK, back to sound waves in air. Speed of Sound vs. If you put this together, you can get a plot of the speed of sound as a function of altitude. At sea level, the value is right around the 340 m/s mark. Speed vs. the Local Speed of Sound I don’t know if “local speed of sound” is an official term, but I like it. Mach Number I guess I was right (at least according to Wikipedia).

The 6 Most Mind-Blowing Things Ever Discovered in Space #3. A Cold Star Here's the very first lesson you learned about the cosmos: The sun is hot. When you get into the science of it, you realize that you were even more right than you thought: The surface of the sun is about 10,000 degrees Fahrenheit, and several thousand times hotter than that at the core. Photos.comThough you could pretend you were that Nazi guy from Raiders of the Lost Ark. But, scientists have recently discovered that's not always the case. Photos.comYou could be the first prostitute to work a star. How is This Even Possible? WISE 1828+2650 is part of a small group of cold stars known as brown dwarfs. Via Earthsky.orgNo, you're doing great, little guy. #2. Via Wikimedia Commons The hardest part of understanding anything about space is trying to grasp a sense of scale. Via VJkrishna.com"Y'all ain't shit." But now imagine a star that is as big compared to the sun as the sun is to the Earth. Via WikipediaFatass. That's the star VY Canis Majoris. How Is This Even Possible? #1.

Secouchermoinsbete.fr : le site qui permet de briller en soirée Why Humans Prevailed NEW YORK — One hundred thousand years ago, several humanlike species walked the Earth. There were tribes of stocky Neanderthals eking out an existence in Europe and northwest Asia, and bands of cave-dwelling Denisovans in Asia. A diminutive, hobbitlike people called Homo floresiensis inhabited Indonesia. What were essentially modern humans roamed Africa. Then, about 60,000 years ago, a few thousand of those humans migrated out of Africa. Why did we prevail? First, although Neanderthals had as big a brain as anyone, the shapes of their fossilized skulls indicate humans had slightly larger frontal lobes, said Chris Stringer, a paleoanthropologist at the Natural History Museum in London. This would suggest brains won out over brawn, and that rather than destroying our enemies in some epic battle, our ancestors may simply have been savvier survivors, steadily growing our numbers while our burlier brethren met their demise. Braininess helped us broaden our diets, for example.

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