Physics news

[Henry J]

First Matter

When the first matter came into being right after the Big Bang, what was it like? It may not have been quite as scientists have been describing it. That is one of the possibilities raised by four international teams of researchers that are about to publish important results three years into an experiment to recreate the primordial matter of the universe.

[lswot]

First Matter

When the first matter came into being right after the Big Bang, what was it like? It may not have been quite as scientists have been describing it. That is one of the possibilities raised by four international teams of researchers that are about to publish important results three years into an experiment to recreate the primordial matter of the universe.

As if.......

[Henry J]

Pi seems a good random number generator – but not always the best

If you wanted a random number, historically you could do worse than to pick a sequence from the string of digits in pi. But Purdue University scientists now say other sources might be better.

(Pi are square?)

Henry

[lswot]

Pi seems a good random number generator – but not always the best

If you wanted a random number, historically you could do worse than to pick a sequence from the string of digits in pi. But Purdue University scientists now say other sources might be better.

(Pi are square?)

Henry

Apple or Cherry?

[Henry J]

Pumpkin

[lswot]

There ya go!

[Henry J]

Pentaquark Debate Heats Up

New data from Jefferson Lab shows the θ+ pentaquark doesn't appear in one place it was expected. The result contradicts earlier findings in this same region and adds to the controversy over whether research groups from around the world have caught a glimpse of a pentaquark, a particle built of five quarks.

(Quark - not just a bartender on DS9!)

***

[lswot]

FIVE Quarks!!!!! Are we talking alternate universes here?

ummm, Pentaquark / pentagon?

quark today gon tomorrow?

[brian]

While light travels at 186,300 miles per second in a vacuum, its speed changes in different media. In February 1999, Danish physicist Lene Vestergaard Hau slowed light to just 38 miles per hour by sending it through an extremely cold cloud of sodium atoms. One year later, physicists at the N.E.C. Research Institute in Princeton, NJ, made light travel 300 times faster than its vacuum speed, so fast it seemed to exit the test chamber while it was still entering. But how can light travel faster than itself?

Light is energy given off by electrons shifting from a higher orbit around an atom's nucleus to a lower orbit. The lost energy causes electric and magnetic fields around the atom to vibrate, giving off waves with specific frequencies. These waves make up the electromagnetic spectrum, part of which appears as light. Scientists can slow down light by forcing it to collide with other waves.

The Princeton physicists used this same technique to speed up light, exposing it to waves that moved in harmony with the beam of light. Just as ocean waves will amplify each other, one wave forcing another quickly to the shore, the experiment caused some of the light waves to accelerate. Because light travels in packets, or pulses, some of the pulses were pushed faster than others, and seemed to exit the chamber while the beam was still entering.

At first, the results of the experiment seem at odds with the central idea of Einstein's Theory of Special Relativity, which holds that nothing travels faster than light. Physicists, however, point out that the news media overstated the significance of the test. Einstein meant nothing with mass travels faster than light, and because light has no mass, his theory still holds true.

[Henry J]

Re "and because light has no mass, "

Um. Light has no rest mass. It does have energy, which has mass or at least mass equivalent. (My understanding is that mass is itself a form of energy.)

But did they send actual energy faster than light, or was what they sent just a waveform? And how much distance are we talking here? I mean, if they sent it across light years we could be on the verge of subspace radio here...

Henry

[lswot]

In February 1999, Danish physicist Lene Vestergaard Hau slowed light to just 38 miles per hour by sending it through an extremely cold cloud of sodium atoms.

Um, they never heard of cloud cover?

Um, I turn on the light switch and the room brightens.

[Xjmt]

While there's nothing much happening at the site right now I thought I'd pass along a splurb from http://www.symmetrymagazine.org

PIXEL ART

Inspired by the pixel structure of far away objects in astronomical images, artist Tim Otto Roth uses live scientific data to create visions of science in action. His artwork, entitled I SEE WHAT I SEE NOT, relies on data from five laboratories in Europe and North America to illuminate a huge outdoor display of 76 individually controllable panels in Munich, Germany.

In December, he transformed images from the German KASCADE cosmic ray experiment into squaes of rapidly changing colors. Projected onto the 700 square foot array, the artwork becomes "a super-eye, looking for the causes of space and matter."

Future imagery will rely on data from particle collider experiments at FERMILAB & SLAC, as well as from two astronomical observatories.

http://www.kunstfassade.de/tor/current_e.html

[Henry J]

Underground physics: Searching for neutrinos in deep places

A new physics experiment combines thousands of tons of steel plates, a powerful particle accelerator and 450 miles of solid rock to reveal the secrets of a particle that sometimes seems to barely exist.

[brian]

Sounds like a sci-fi western song. Maybe it'll be on the Serenity soundtrack: "Looking for neutrinos in all the deep places..."

Or, "I've got neutrinos in deep places..."

[lswot]

Sounds like a sci-fi western song. Maybe it'll be on the Serenity soundtrack: "Looking for neutrinos in all the deep places..."

Or, "I've got neutrinos in deep places..."

or....."looking for neutrinos in all the deep places"