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Now you see it, now you don’t

10/08/2011

Greetings all! Two little pieces of science in the news I want to bring to your attention. Firstly the invisibility cloak is looking more clear now!

Light speed hurdle to invisibility

cloak overcome by undergraduate

(PhysOrg.com) — An undergraduate student has overcome a major hurdle in the development of invisibility cloaks by adding an optical device into their design that not only remains invisible itself, but also has the ability to slow down light.

The optical device, known as an ‘invisible sphere’, would slow down all of the light that approaches a potential cloak, meaning that the light rays would not need to be accelerated around the cloaked objects at great speeds ― a requirement that has limited invisibility cloaks to work only in a specified region of the visible spectrum.

This new research, published today, Tuesday 9 August, in the Institute of Physics and German Physical Society’s New Journal of Physics, could open up the possibility for a potential invisibility cloak wearer to move around amongst ever-changing backgrounds of a variety of colours.

Under the guidance of Professor Ulf Leonhardt, Janos Perczel, originating from Hungary and reading Logic, Philosophy of Science and Physics at the University of St Andrews, acknowledged the huge potential of the invisible sphere and was able to fine-tune it so that it was a suitable background for cloaking.

The usual approach to designing an invisibility cloak works on the basis of bending light ― using highly specific materials ― around an object that you wish to conceal, thereby preventing the light from hitting the object and revealing its presence to the eye of the observer.

When the light is bent, it engulfs the object, much like water covering a rock sitting in a river bed, and carries on its path making it seem as if nothing is there.

Light, however, can only be accelerated to a speed faster than it would travel in space under certain conditions, and this restricts invisibility cloaks to work in a limited part of the spectrum ― essentially just one colour.

Source: http://topicfire.com/share/Light-speed-hurdle-to-invisibility-cloak-overcome-by-undergraduate-18023529.html

Weird huh? Something to do with Euclidean geometry what ever that is.

Figure 1. A Euclidean cloaking device expands a single point in virtual space (blue dot in (A)) into an extended region in physical space (blue circle in (B)) through the curved transformation of the virtual coordinate grid. A light ray that is smoothly guided around the invisible region in physical space (B) appears to have passed through empty space (A), making the region within the blue circle (B) invisible. However, along the blue circle the phase velocity of light goes to infinity.

Science paper : http://iopscience.iop.org/1367-2630/13/8/083007/pdf/1367-2630_13_8_083007.pdf

Basically it involves bending light and refracting it to create the illusion of invisibility. The journal link above has all kinds of equations and stuff if that floats your boat.

Speaking of things that float, the Tsunami in Japan had far reaching implications it seems.

Japan Tsunami Broke Off Icebergs in Antarctica

New space-based images show the same tsunami that devastated Japan also caused a series of giant icebergs to break off halfway around the world in Antarctica.

On March 11, a magnitude 9.0 earthquake struck off the east coast of Japan. Combined with the tsunami it unleashed, the event led to the deaths of at least 15,000 people and inflicted damage costing upwards of $235 billion.

Yet the destructive wave didn’t just crush Japanese shores. The tsunami rippled through the Pacific Ocean, bent around New Zealand and hit Antarctica after a little more than 18 hours, according to an upcoming study in the Journal of Glaciology.

“This [is] the first observational evidence linking a tsunami to ice-shelf calving,” the authors wrote in the study, released by NASA today.

The tsunami only reached a foot high after traveling 8,000 miles to the Sulzberger Ice Shelf, but the European Space Agency satellite Envisat was able to survey the damage through thick cloud cover with its radar instruments.

In total, the tsunami liberated about 48 square miles of icebergs from a region that had remained essentially unchanged for close to half a century. The largest iceberg that calved off of the Sulzberger Ice Shelf into the Ross Sea measured about 7 miles long by 4 miles wide.

Sea ice is basically frozen sea which because it is made of salt, freezes at a little below pure water. That is it needs to be colder for sea ice to form. And there we go back to climate change. Here is another interesting article on sea ice.

Arctic Sea Ice Extent Reaches 32-Year Low

By MARK DUNPHY – Tue Aug 09, 3:31 pm

Arctic sea ice extent averaged for July 2011 reached the lowest level for the month in the 1979 to 2011 satellite record, even though the pace of ice loss slowed substantially during the last two weeks of July.

That’s according to the National Snow and Ice Data Center (NSIDC) which noted that shipping routes in the Arctic have less ice than usual for this time of year. The NSIDC also said that new data indicate that more of the Arctic’s store of its oldest ice disappeared.

Source: http://www.irishweatheronline.com/news/earth-science/glaciology/arctic-sea-ice-extent-reaches-32-year-low/31268.html

The funny thing in all this is how this relates to the debate on climate change in this country. While Tony Abbott does his all singing all dancing “scientists and economists are stupid and CO2 is weightless” routine around the country, it shames me to see that some have fallen for his illusion.

His deception.

His lie.

His use of Euclidean geometry to cloak the reality of climate change.

The science is clear. The data is in. The planet is warming. Climate change is happening. And we know why.

Still. We do get distracted so easily. Your job is to work out what is actually happening or you can prefer to go with the illusion that CO2 is weightless.

Oh by the way, here is a riddle for you.

What weighs more. A kilogram of coal or a kilogram of CO2?

Answer in the next blog! Promise! Until then, allow me to distract you some more.

A. Ghebranious 2011 (All rights preserved in a little formaldehyde. Just checking to see if anyone reads the last line much)

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One Comment
  1. Jennifer Baratta permalink

    Thanks Ash

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