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STEPHEN HAWKING: How to build a time machine. By STEPHEN HAWKING Created: 18:47 GMT, 27 April 2010 All you need is a wormhole, the Large Hadron Collider or a rocket that goes really, really fast 'Through the wormhole, the scientist can see himself as he was one minute ago.

STEPHEN HAWKING: How to build a time machine

But what if our scientist uses the wormhole to shoot his earlier self? He's now dead. Hello. Time travel was once considered scientific heresy. To see how this might be possible, we need to look at time as physicists do - at the fourth dimension. But there is another kind of length, a length in time. To see what that means, let's imagine we're doing a bit of normal, everyday car travel. Let's indulge in a little science fiction for a moment. Physicists have been thinking about tunnels in time too, but we come at it from a different angle. Enlarge Nothing is flat or solid. SMN_NEW_Daylight09MAR09.gif from - StumbleUpon.

Cell Size and Scale. Some cells are visible to the unaided eye The smallest objects that the unaided human eye can see are about 0.1 mm long.

Cell Size and Scale

That means that under the right conditions, you might be able to see an ameoba proteus, a human egg, and a paramecium without using magnification. A magnifying glass can help you to see them more clearly, but they will still look tiny. Smaller cells are easily visible under a light microscope. It's even possible to make out structures within the cell, such as the nucleus, mitochondria and chloroplasts. To see anything smaller than 500 nm, you will need an electron microscope. How can an X chromosome be nearly as big as the head of the sperm cell? People.htm from Perpetual Futility A short history of the search for perpetual motion. by Donald E.

people.htm from

Simanek Popular histories too often present perpetual motion machines as "freaks and curiosities" of engineering without telling us just how they were understood at the time. They also fail to inform us that even in the earliest history of science and engineering, many persons were able to see the futility and folly of attempts to achieve perpetual motion. Sometimes a particular device comes to us with a label, such as "Bishop Wilkins' magnetic perpetual motion machine. " Popular articles leave the impression that the inventor believed it was a perpetual motion machine. Bhaskara's Wheels. Villard de Honnecourt was born in the late 12th century and probably lived and worked in the north of France from 1225 to 1250.

Tesla: Master of Lightning. The Elegant Universe: Pt 1. The Elegant Universe: Part 3 PBS Airdate: November 4, 2003 NARRATOR: Now, on NOVA, take a thrill ride into a world stranger than science fiction, where you play the game by breaking some rules, where a new view of the universe pushes you beyond the limits of your wildest imagination.

The Elegant Universe: Pt 1

This is the world of "string theory," a way of describing every force and all matter from an atom to earth, to the end of the galaxies—from the birth of time to its final tick, in a single theory, a "Theory of Everything. " Our guide to this brave new world is Brian Greene, the bestselling author and physicist.

BRIAN GREENE (Columbia University): And no matter how many times I come here, I never seem to get used to it. NARRATOR: Can he help us solve the greatest puzzle of modern physics—that our understanding of the universe is based on two sets of laws that don't agree? NARRATOR: Resolving that contradiction eluded even Einstein, who made it his final quest. S. Physical Quantities. Scientific Curiosity Captured in Photos. Caleb Charland is a Maine-based photographer who combines a love of scientific experiments and photographs into wonderful and amazing photographs.

Scientific Curiosity Captured in Photos

If Isaac Newton or Benjamin Franklin were into photography, their photographs might look something like these: Heavy Boots - StumbleUpon. Editorial note: I received this as an email from a friend who got it from a friend who ...

Heavy Boots - StumbleUpon

I do not know who the original author is, but I do believe this to be true. Who could possibly make it up? Heavy Boots About 6-7 years ago, I was in a philosophy class at the University of Wisconsin, Madison (good science/engineering school) and the teaching assistant was explaining Descartes. He was trying to show how things don't always happen the way we think they will and explained that, while a pen always falls when you drop it on Earth, it would just float away if you let go of it on the Moon. My jaw dropped a little. "No it wouldn't. " the TA explained calmly, "because you're too far away from the Earth's gravity. " I countered, "why didn't they float away? " "Because they were wearing heavy boots. " he responded, as if this made perfect sense (remember, this is a Philosophy TA who's had plenty of logic classes). As we left the room, my friend Mark was raging.

Non-Newtonian Fluid on a Speaker Cone. How to turn "water" into marbles. Rubens Tube. Imagining the Tenth Dimension - A Book by Rob Bryanton.