Clipmarks | Particle spin Clips

Large Hadron Collider to Have "Practical" Spin-Offs?

Sat, 13 Sep 2008 21:01:12 GMT

clipped by: A53GG4

Clip Source: news.nationalgeographic.com

Large Hadron Collider to Have "Practical" Spin-Offs?

September 12, 2008

A multibillion-dollar atom smasher on the Franco-Swiss border may help scientists treat diseases, improve the Internet, and open the door to travel through extra dimensions, according to physicists.

On Wednesday scientists cheered and champagne flowed as the first beam of protons lapped around the Large Hadron Collider's (LHC) 17-mile (27-kilometer) underground tunnel at the European Organization for Nuclear Research.

The collider, the world's largest particle accelerator, was designed to solve big mysteries in science, such as the nature of dark matter and what the universe was like just after the big bang.

The massive machine could also lead to medical and technological advances, some experts argue.

Continued on Next Page >>

Tags: science

'Grid' Could Make Internet Obsolete

Wed, 09 Apr 2008 06:20:14 GMT

clipped by: misterboh

Clip Source: www.foxnews.com

The Internet could soon be made obsolete. The scientists who pioneered it have now built a lightning-fast replacement capable of downloading entire feature films within seconds.

At speeds about 10,000 times faster than a typical broadband connection, “the grid” will be able to send the entire Rolling Stones back catalogue from Britain to Japan in less than two seconds.

The latest spin-off from Cern, the particle physics centre that created the web, the grid could also provide the kind of power needed to transmit holographic images; allow instant online gaming with hundreds of thousands of players; and offer high-definition video telephony for the price of a local call.

Tags: internet, web 3.0, cern

'The Grid' Could Soon Make the Internet Obsolete

Mon, 07 Apr 2008 10:54:05 GMT

clipped by: Newfman

Clip Source: www.foxnews.com

The Internet could soon be made obsolete. The scientists who pioneered it have now built a lightning-fast replacement capable of downloading entire feature films within seconds.

At speeds about 10,000 times faster than a typical broadband connection, “the grid” will be able to send the entire Rolling Stones back catalogue from Britain to Japan in less than two seconds.

David Britton, professor of physics at Glasgow University and a leading figure in the grid project, believes grid technologies could “revolutionise” society. “With this kind of computing power, future generations will have the ability to collaborate and communicate in ways older people like me cannot even imagine,” he said.

Evolution of the Internet

Mon, 07 Apr 2008 01:35:27 GMT

clipped by: Lara Nieberding
clipper's remarks: Jonathan Leake at Times Online explains "the grid."

Clip Source: www.timesonline.co.uk

Coming soon: superfast internet

Jonathan Leake, Science Editor

THE internet could soon be made obsolete. The scientists who pioneered it have now built a lightning-fast replacement capable of downloading entire feature films within seconds.

At speeds about 10,000 times faster than a typical broadband connection, “the grid” will be able to send the entire Rolling Stones back catalogue from Britain to Japan in less than two seconds.

By contrast, the grid has been built with dedicated fibre optic cables and modern routing centres, meaning there are no outdated components to slow the deluge of data. The 55,000 servers already installed are expected to rise to 200,000 within the next two years.

Tags: times online, jonathan leake, internet, grid

Physicists Discover How Fundamental Particles Lose Track of Quantum Mechanical Properties

Thu, 13 Mar 2008 22:52:11 GMT

clipped by: arifsali

Clip Source: www.ia.ucsb.edu

In today's Science Express, the advance online publication of the journal Science, researchers report a series of experiments that mark an important step toward understanding a longstanding fundamental physics problem of quantum mechanics.

The problem the physicists addressed is how a fundamental particle in matter loses track of its quantum mechanical properties through interactions with its environment.

The research was performed by scientists at the California NanoSystems Institute at the University of California, Santa Barbara and the U. S. Department of Energy Ames Laboratory in Iowa.

At the quantum level things like particles or light waves behave in ways very different from what scientists expect in a human-scale world. In the quantum world, for example, an electron can exist in two places at the same time, what is called a "superposition" of states, or spin up and down at the same time.

Tags: quantum mechanics, science

Entanglement Art: Dawn Meson

Sun, 13 Jan 2008 18:51:54 GMT

clipped by: abailart

Clip Source: www.symmetrymagazine.org

Entanglement I,

Entanglement II

Meson was attracted to the subject of particle entanglement and action at a distance because it poses a mystery. "Wacky things do happen and have mathematical bases," she says. Each of the two canvases shows a particle; similar in their coloration to show that they are the same type of particle, for example both electrons. Painting unseen particles at such detail presented challenges. Meson had to devise visual analogies to such abstract concepts such as spin. "Spin has nothing to do with visual reality." She painted the particles to spiral in opposite directions as a symbol for having opposite spin. Like entangled particles, the paintings began physically joined, but the two canvases can be placed far from each other in a room and still maintain a connection.

Collision II

"Spin has nothing
to do with visual reality."
Dawn Meson

Tags: art and science, representation, quantum entanglement

Quantum Entanglement

Sun, 13 Jan 2008 17:11:02 GMT

clipped by: abailart

Clip Source: searchcio-midmarket.techtarget.com

Entanglement is a term used in quantum theory to describe the way that particles of energy/matter can become correlated to predictably interact with each other regardless of how far apart they are.

Entanglement is a real phenomenon (Einstein called it "spooky action at a distance"), which has been demonstrated repeatedly through experimentation.

Quantum entanglement allows qubits that are separated by incredible distances to interact with each other immediately, in a communication that is not limited to the speed of light. No matter how great the distance between the correlated particles, they will remain entangled as long as they are isolated.

Knowing the spin state of one entangled particle - whether the direction of the spin is up or down - allows one to know that the spin of its mate is in the opposite direction.

measured particle has no single spin direction before being measured, but is simultaneously in both a spin-up and spin-down state

Tags: quantum entanglement

Spinning particles hold the promise of almost unlimited computing power

Wed, 08 Aug 2007 10:07:52 GMT

clipped by: JohnWaterman

Clip Source: news.bbc.co.uk

When engineers flick the switch to turn on the world's fastest supercomputer later this year it will be capable of chewing its way through 1,000 trillion calculations every second

But this speedy number cruncher could soon look like the equivalent of a dusty abacus if scientists who have gathered in York deliver on their promises.

explore the future of spintronics (spin-based electronics), an area that could have profound effects

With quantum computing you are able to attack some problems on the time scales of seconds, which might take an almost infinite amount of time with classical computers,

Spintronics, also known as magnetoelectronics, is an emerging technology that harnesses the spin of particles.

by harnessing the twist and turns of particles - detected as a weak magnetic force - scientists hope to unlock almost infinite computing power and storage, without the heat

"You can store an almost infinite number of bits of information in one particle space," he added.

Tags: technology, science, computing, quantum, particle spin

Old-School Hi Tech

Wed, 11 Jul 2007 19:25:23 GMT

clipped by: bidwell
clipper's remarks: Nice work, young man....

Clip Source: www.emergetrends.com

Kartik Madiraju- in a move that's at once innovative and reminscent of an era of innovation that seemed far behind us- has invented a new source of ecologically benign energy. In contrast to the complex sorts of experiments going on night and day at particle accelerators around the world, Madiraju, a 16-year old student from Montreal, happened across an amazingly simple way to generate electricity. His solution, with potential applications ranging from clean-running powerplants to micro-power sources for nanotechnologies?

Magnetic bacteria.

Madiraju has found a way to generate roughly half the power of a standard AA battery with about an ounce of the bacteria- which is commonly found in water- for 48 hours. The magnetotactic bacteria, which he learned about reading Nature, are placed free-floating into tiny plastic bottles with metal strips on the sides serving as electrodes, causing crystals of magnetite inside the bacteria to spin and generate a magnetic field and electrical current.

Tags: science, invention, energy

Quantum Mechanics the Easy Way

Mon, 15 Jan 2007 00:48:42 GMT

clipped by: destino
clipper's remarks: A great overview of quantum mechanics from.

Clip Source: www.scottaaronson.com

There are two ways to teach quantum mechanics. The first way -- which for most physicists today is still the only way -- follows the historical order in which the ideas were discovered. So, you start with classical mechanics and electrodynamics, solving lots of grueling differential equations at every step. Then you learn about the "blackbody paradox" and various strange experimental results, and the great crisis these things posed for physics. Next you learn a complicated patchwork of ideas that physicists invented between 1900 and 1926 to try to make the crisis go away. Then, if you're lucky, after years of study you finally get around to the central conceptual point: that nature is described not by probabilities (which are always nonnegative), but by numbers called amplitudes that can be positive, negative, or even complex.

As a direct result of this "QWERTY" approach to explaining quantum mechanics - which you can see reflected in almost every popular book and article, down to the present -- the subject acquired an undeserved reputation for being hard. Educated people memorized the slogans -- "light is both a wave and a particle," "the cat is neither dead nor alive until you look," "you can ask about the position or the momentum, but not both," "one particle instantly learns the spin of the other through spooky action-at-a-distance," etc. -- and also learned that they shouldn't even try to understand such things without years of painstaking work.

The second way to teach quantum mechanics leaves a blow-by-blow account of its discovery to the historians, and instead starts directly from the conceptual core -- namely, a certain generalization of probability theory to allow minus signs. Once you know what the theory is actually about, you can then sprinkle in physics to taste, and calculate the spectrum of whatever atom you want. This second approach is the one I'll be following here.

Tags: quantum mechanics, physics, science

Is there a need for two measurements?

Mon, 06 Nov 2006 12:19:06 GMT

clipped by: peterclip
clipper's remarks: What if one could make only one measurement

Clip Source: www.srcf.ucam.org

Fortunately, this ‘action at a distance’ turns out to be a very unusual beast. At first sight, it might appear to be very powerful. However, that is not so: the second electron’s change in state cannot be used to transmit any sort of message. Before the experimenter measures the spin of the first electron, the second electron has no definite spin value; if its spin were to be measured at this point, there would be an equal chance of finding it to be spin-up or spin-down. After the measurement on the first electron, the second electron suddenly acquires a definite spin value, opposite to that of the first electron. However, there is no way to distinguish between these two states of affairs with only one measurement. Just as detecting a photon on a screen pins down its position, measuring the spin of a particle pins that down also, kicking it out of its previous state. Subsequent measurements will always find the same value. If we could make copies of the second electron before we measured it, we could do it — if the spins of all the copies came out the same, we would know the state of the first electron had been measured — but quantum mechanics tells us that there is no way to copy an unknown state. This is known as the no-cloning theorem, and is quite inescapable.

However, there is no way to distinguish between these two states of affairs with only one measurement. J

Tags: quantum entanglement

Massive Spider Web

Sat, 28 Oct 2006 18:36:34 GMT

clipped by: songbirdgp

Clip Source: flatrock.org.nz

Millions of Tiny Spiders Spin Mystery in a British Columbia Clover Field

Experience is never limited, and it is never complete; it is an immense sensibility, a kind of huge spider-web of the finest silken threads suspended in the chamber of consciousness, and catching every air-borne particle in its tissue.

Tags: spiders, web, creepy

the metric and its inverse

Sat, 28 Oct 2006 12:37:26 GMT

clipped by: peterclip
clipper's remarks: John Baez's article on Ted Jacobson

Clip Source: math.ucr.edu

One can imagine a world where the metric g_{ab} is

-1  0  0  0
 0  1  0  0
 0  0  k  0
 0  0  0  k

Another way to formulate general relativity uses the inverse metric g^{ab}. This is just the inverse of the matrix g_{ab}, which is indeed invertible when the metric is nondegenerate. So for example in the above case the inverse metric g^{ab} is

-1  0  0  0
 0  1  0  0
 0  0  K  0
 0  0  0  K

where K = 1/k. You can think of K as the speed of light in the y and z directions, which is different from the speed of light in the x direction.

-1  0  0  0
 0  1  0  0
 0  0  0  0
 0  0  0  0

so the inverse metric doesn't even make sense --- you can't invert this matrix. If we extend general relativity to degenerate metrics, we are allowing ourselves to study weird worlds like this. Why we'd want to --- well, that's another matter.

If we work with the inverse metric, we can't let k = 0, but we can let K = 0. This corresponds to making the speed of light in the y and z directions *zero*, so that information can't go at all in those directions: the lightcone is squashed down onto the t-x plane. Now it's the inverse metric that equals

-1  0  0  0
 0  1  0  0
 0  0  0  0
 0  0  0  0

and the metric doesn't even make sense.

Ted Jacobson's talk was about doing general relativity in weird worlds like this, where the inverse metric is degenerate. Here information flows only along surfaces, like the x-t plane in the example above, and these different surfaces don't really talk to each other very much. It's as if the world was split up (or in math jargon, foliated) into lots of different 2-dimensional worlds, which didn't know about each other. Jacobson showed that in this case, the equations of general relativity (extended in a certain way to degenerate inverse metrics) boil down to saying that there are two kinds of massless spin-1/2 particle living on all these 2-dimensional worlds.

Tags: mathy physics

"online textbook"

Sat, 12 Aug 2006 02:07:58 GMT

clipped by: skwirlinator
clipper's remarks:

This "online textbook" is designed to provide a thorough, in-depth treatment of this topic at the first-year college or advanced-HS levels, with a special focus on the underlying concepts.

Clip Source: www.chem1.com

This "online textbook" is designed to provide a thorough, in-depth treatment of this topic at the first-year college or advanced-HS levels, with a special focus on the underlying concepts.

1- Quanta: a new view of the world

The limits of classical physics

The quantum revolution

Radiation is quantized

The photoelectric effect

Matter and energy united

concept map

2- Light, particles and waves

The language of light

Light a particle: the photon

Light as electromagnetic radiation

Spectra: interaction of light with matter

Wavelength of a particle

The uncertainty principle

Spectrum of a guitar string

Standing waves in the hydrogen atom

The hydrogen spectrum explained

Emission and absorption spectrum; Fraunhofer lines

concept map

4- The quantum atom

The wave function and its physical meaning

Why doesn't the electron fall into the nucleus?

Quantum numbers of electrons in atoms

Electron spin and the Pauli exclusion principle

concept map

5- Atomic electron configurations

Atoms that have only one electron

Effects of electron-electron repulsion

The Aufbau rules

The periodic table

concept map

6- Periodic properties of the elements

How the periodic table is organized

The shell model of the atom

Effective nuclear charge

Sizes of atoms and ions

Ionization energies

Electron affinities

Electronegativity

References and periodic table links

concept map

Among the many sources the author drew upon, special mention should be made of Pimentel and Spratley’s Understanding Chemistry, S. Brush’s Introduction to Concepts and Theories in Physical Science, P. Atkin’s Quanta, P. Davies’ The Forces of Nature, and the inspired writing of Toulmin and Goodfield in The Architecture of Matter.

Click one of the six lesson titles immediately below on the left;
you can also go directly to any sub-section within a lesson.

Tags: online learning, chemestry, physics, science, knowledge, understanding

Clipmarks | Particle spin Clips

Large Hadron Collider to Have "Practical" Spin-Offs?

Large Hadron Collider to Have "Practical" Spin-Offs?

'Grid' Could Make Internet Obsolete

'The Grid' Could Soon Make the Internet Obsolete

Evolution of the Internet

Coming soon: superfast internet

Physicists Discover How Fundamental Particles Lose Track of Quantum Mechanical Properties

Entanglement Art: Dawn Meson

Quantum Entanglement

Spinning particles hold the promise of almost unlimited computing power

Old-School Hi Tech

Quantum Mechanics the *Easy* Way

Is there a need for two measurements?

Massive Spider Web

Millions of Tiny Spiders Spin Mystery in a British Columbia Clover Field

the metric and its inverse

"online textbook"

Quantum Mechanics the Easy Way