Post Tagged with: "physics"

There Is No Way to Stop Space Rocks From Hurtling to Earth and Killing You

There Is No Way to Stop Space Rocks From Hurtling to Earth and Killing You

I just finished a new Psychetect track last night. Hopefully I’ll be able to share it with you before Space Kills Us All:

Space is out to kill you. There is no way to stem its aggression. But it’s usually an incompetent killer, so don’t freak out. [...]

All the advanced air defenses that humanity has invested in? The interceptor missile that are (sometimes) able to stop an adversary missile from impacting? The early-warning monitoring systems that are supposed to give humanity enough time to plan a response? They are useless, useless against a meteorite onslaught. Do not believe the stories about the Russians shooting the cosmic rock down. [...]

But there’s good news. Space rocks are lousy shots. The Earth is mostly ocean and uninhabited areas. The frequency of meteorite impacts is correlated with size, Weeden explains, and the smaller the meteorites, the more often they land. “But the places where people are is actually pretty small,” he says. Even the injuries that occurred at Chelyabinsk were mostly concussions and accidents from shattered glass, not from the meteorite itself. Close but no cigar, space: “Your odds of dying by a meteor are pretty damn small. You’re thousands of times more likely to die by car on way to work.”

Full Story: Wired Danger Room: There Is No Way to Stop Space Rocks From Hurtling to Earth and Killing You

Man, Space must really hate Siberia.

February 15, 2013 1 comment
Scientists Cast Doubt On Heisenberg’s Uncertainty Principle

Scientists Cast Doubt On Heisenberg’s Uncertainty Principle

Science Daily reports:

Werner Heisenberg’s uncertainty principle, formulated by the theoretical physicist in 1927, is one of the cornerstones of quantum mechanics. In its most familiar form, it says that it is impossible to measure anything without disturbing it. For instance, any attempt to measure a particle’s position must randomly change its speed.

The principle has bedeviled quantum physicists for nearly a century, until recently, when researchers at the University of Toronto demonstrated the ability to directly measure the disturbance and confirm that Heisenberg was too pessimistic. [...]

The findings build on recent challenges to Heisenberg’s principle by scientists the world over. Nagoya University physicist Masanao Ozawa suggested in 2003 that Heisenberg’s uncertainty principle does not apply to measurement, but could only suggest an indirect way to confirm his predictions. A validation of the sort he proposed was carried out last year by Yuji Hasegawa’s group at the Vienna University of Technology. In 2010, Griffith University scientists Austin Lund and Howard Wiseman showed that weak measurements could be used to characterize the process of measuring a quantum system. However, there were still hurdles to clear as their idea effectively required a small quantum computer, which is difficult to build.

Full Story: Science Daily: Scientists Cast Doubt On Heisenberg’s Uncertainty Principle

December 10, 2012 1 comment
Higgs Boson Discovery May Not Be So Exciting After All

Higgs Boson Discovery May Not Be So Exciting After All

From the Guardian a couple weeks ago:

Scientists working at the Large Hadron Collider have found no evidence that the new particle discovered earlier this year is anything but the simplest – and most boring – variety of Higgs boson.

Staff at Cern, the particle physics lab near Geneva, celebrated in July after they found what looked like the elusive boson amid the debris of scores of high-energy collisions inside the huge machine.

At the time, preliminary results from the two main experiments, Atlas and CMS, hinted that the particle might be something more exciting than the singular beast originally described in equations nearly 50 years ago. A more exotic Higgs could pave the way to a profound new understanding of nature.

But fresh data released by both teams at a conference in Kyoto today show that – so far at least – there is nothing peculiar about the particle’s behaviour. The results do not completely rule out a more exotic Higgs particle, though. Some versions would look so much like the so-called Standard Model Higgs boson they could take years to identify.

Full Story: The Guardian: Higgs particle looks like a bog Standard Model boson, say scientists

Previously: New Particle Resembling Long-Sought Higgs Boson Uncovered at Large Hadron Collider

November 30, 2012 0 comments
How An Anti-Feminist Screed Ended Up In a Physics Journal

How An Anti-Feminist Screed Ended Up In a Physics Journal

Zen Faulkes explains how an issue of the Canadian Journal of Physics dedicated to chaos theory ended up running an anti-feminist screed that reportedly claimed that “half the children of working mothers suffered ‘serious psychological damage.’”

The article was penned by Gordon Freeman (pictured), who was the guest editor of this one issue of the journal. It was pretty obvious what had happened, in broad strokes: he abused his editorial power to get his poisonous opinion piece into the pages of the journal.

The details of exactly how this happened were a little more complicated. Freeman organized a conference on chaos theory, and was assembling papers that had been presented at a conference for publication in the Canadian Journal of Physics. Apparently, the deal was that the journal would publish all the papers Freeman compiled, provided that they were presented at the conference, and that they were peer-reviewed.

Full Story: Neurodojo: Retraction classic: Physics and feminism

October 17, 2012 0 comments
XKCD Creator Randall Munroe On Making Physics Fun

XKCD Creator Randall Munroe On Making Physics Fun

XKCD creator Randall Munroe on his work, including his new What If? series.

First things first: Why did you create What If?

It actually started with a class. MIT has a weekend program where volunteers can teach classes to groups of high school students on any subject you want. I had a friend who was doing it, and it sounded really cool — so I signed up to teach a class about energy, which I always thought was interesting, but which is a slippery idea to define. I was really getting into the nuts and bolts of what energy is, and it was a lot of fun — but when I started to get into the normal lecture part of the class, it felt kind of dry, and I could tell the kids weren’t super into it. And then we got to a part where I brought up an example — I think it was Yoda in Star Wars. And they got really excited about that. And then they started throwing out more questions about different movies — like, “When the Eye of Sauron exploded at the end of The Lord of the Rings, and knocked people over from this far away, can we tell how big a blast that was?” They got really excited about that — and I had a lot more fun doing it than I did just teaching the regular material.

So I spent the second half of the class just solving problems like that in front of them. And then I was like, “That was really fun. I want to keep doing it.”

Full Story: The Atlantic: A Conversation With Randall Munroe, the Creator of XKCD

September 28, 2012 0 comments
Researchers Propose A Way To Build The First Space-Time Crystal

Researchers Propose A Way To Build The First Space-Time Crystal

Imagine a clock that will keep perfect time forever, even after the heat-death of the universe. This is the “wow” factor behind a device known as a “space-time crystal,” a four-dimensional crystal that has periodic structure in time as well as space. However, there are also practical and important scientific reasons for constructing a space-time crystal. With such a 4D crystal, scientists would have a new and more effective means by which to study how complex physical properties and behaviors emerge from the collective interactions of large numbers of individual particles, the so-called many-body problem of physics. A space-time crystal could also be used to study phenomena in the quantum world, such as entanglement, in which an action on one particle impacts another particle even if the two particles are separated by vast distances.

A space-time crystal, however, has only existed as a concept in the minds of theoretical scientists with no serious idea as to how to actually build one – until now.

ECN: A clock that will last forever

(Thanks Bill)

September 26, 2012 0 comments
Quantum Encryption Becomes A Little Less Impractical

Quantum Encryption Becomes A Little Less Impractical

From Bob McMillan at Wired Enterprise:

Sharing encryption keys the quantum way is exciting because it promises to be an incredibly secure way of doing encryption. In quantum cryptography, the encryption key is read by measuring the polarization of the photons being sent between computers. And according to Heisenberg’s uncertainty principle, anyone listening in on the communications would have to start messing with that polarization. And that would be detectable.

Up until now, the photons used to exchange quantum keys have been built using external lasers. But this new laser-free technique would be cheaper to mass-produce, says Sven Höfling, a group leader with the applied physics department at Würzburg University. “We can make Quantum key distribution with electrically driven sources,” he says. This is really compatible with standard semiconductor technology, meaning it could be, in principle, very cheap.”

Wired Enterprise: Quantum Crypto Takes Practical Step With Photon Breakthrough

Bob also notes that this may never actually be a practical technology.

Disclosure: I work for Wired Enterprise

August 7, 2012 0 comments
New Particle Resembling Long-Sought Higgs Boson Uncovered at Large Hadron Collider

New Particle Resembling Long-Sought Higgs Boson Uncovered at Large Hadron Collider

As you’ve likely heard, both the ATLAS and CMS teams at the Large Hadron Collider believe they’ve found the Higgs Boson:

Crucially, both teams’ findings appear exceptionally robust. In physics terms, evidence for a new particle requires a “3-sigma” measurement, corresponding to a 1-in-740 chance that a random fluke could explain the observations, and a claim of discovery requires a 5-sigma effect, or a 1-in–3.5 million shot that the observations are due to chance. In December representatives of the two experiments had announced what one called “intriguing, tantalizing hints” of something brewing in the collider data. But those hints fell short of the 3-sigma level. The new ATLAS finding met not just that level of significance but cleared the gold standard 5-sigma threshold, and CMS very nearly did as well, with a 4.9-sigma finding. [...]

The newfound particle fits the bill for the Higgs boson, but the researchers cautioned that more work is needed to compare the properties of the particle to those predicted for the Higgs. After all, the LHC’s detectors cannot identify the Higgs directly. The LHC accelerates protons to unprecedented energies of four trillion electron-volts (4 TeV) before colliding a clockwise-traveling proton beam with a counterclockwise beam. From the smash-up new particles emerge, some of them existing for just an instant before decaying to other particles.

Full Story: Scientific American: New Particle Resembling Long-Sought Higgs Boson Uncovered at Large Hadron Collider

Previously: CERN May Have Found the Higgs Boson Particle, but Don’t Get Too Excited Yet

July 4, 2012 0 comments
Huge Solar Flare’s Magnetic Storm May Disrupt Satellites, Power Grids

Huge Solar Flare’s Magnetic Storm May Disrupt Satellites, Power Grids

solar flare march

A coronal mass ejection is headed for earth:

A massive solar flare that erupted from the sun late Tuesday (March 6) is unleashing one of the most powerful solar storms in more than five years, a solar tempest that may potentially interfere with satellites in orbit and power grids when it reaches Earth. [...]

“When the shock arrives, the expectation is for heightened geomagnetic storm activity and the potential for heightened solar radiation,” Kunches said.

This heightened geomagnetic activity and increase in solar radiation could impact satellites in space and power grids on the ground. Some high-precision GPS users could also be affected, he said.

“There is the potential for induced currents in power grids,” Kunches said. “Power grid operators have all been alerted. It could start to cause some unwanted induced currents.”

Airplanes that fly over the polar caps could also experience communications issues during this time, and some commercial airliners have already taken precautionary actions, Kunches said. Powerful solar storms can also be hazardous to astronauts in space, and NOAA is working close with NASA’s Johnson Space Center to determine if the six residents of the International Space Station need to take shelter in more protected areas of the orbiting laboratory, he added. Huge Solar Flare’s Magnetic Storm May Disrupt Satellites, Power Grids

(via Jon Mitchell)

March 7, 2012 0 comments
Timeline of the Far Future

Timeline of the Far Future

Wikipedia entry of the day: Timeline of the Far Future. Excerpt:

>50 billion: Assuming both survive the Sun’s expansion, by this time the Earth and the Moon become tidelocked, with each showing only one face to the other.
100 billion: The Universe’s expansion causes all evidence of the Big Bang to disappear beyond the practical observational limit, rendering cosmology impossible.
450 billion: Median point by which the Local Group, the collection of ~47 galaxies to which the Milky Way belongs,[42] will coalesce into a single large galaxy.

(via Substack)

See also: Earth May Exist Forever and Matrioshka Brain.

February 15, 2012 0 comments