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Integrity - use of values or principles to guide action in the situation at hand.

Below are links and discussion related to the values of freedom, hope, trust, privacy, responsibility, safety, and well-being, within business and government situations arising in the areas of security, privacy, technology, corporate governance, sustainability, and CSR.

Cast no shadows, 26.5.06

How to weave a cloak that makes you invisible

IN NORSE mythology, a magic cloak granted invisibility to Sigurd, a demi-god and skilled warrior with superhuman strength. Millennia later, a similar garment bestowed invisibility on Harry Potter, a schoolboy wizard. In the mortal (or Muggle) realm, engineers have for years tried with varying degrees of success to build such a device. This week a team of physicists and materials scientists announced it had devised a pattern for a potentially perfect invisibility cloak.

Light is an electromagnetic wave, with a longer wavelength than X-rays and ultraviolet, and a shorter wavelength than infra-red, microwaves and radio waves. All these electromagnetic waves are governed by four mathematical expressions established almost 150 years ago by James Clerk Maxwell. These equations represent one of the most elegant and concise ways to state the behaviour of electric and magnetic fields and how they interact with matter. However, because they are so concise, they also embody a high level of mathematical sophistication.

The team—Sir John Pendry of Imperial College London with David Schurig and David Smith of Duke University in North Carolina—used the equations to devise a way to cloak an object with a material that would deflect the rays that would have struck it, guide them around it and return them to their original trajectory. Maxwell's equations conserve certain properties—the magnetic field intensity, the electric displacement field and the Poynting vector that describes the electric flux of an electromagnetic field. These properties remain the same when others are altered. The team showed how these fields could be manipulated to flow around objects like a fluid, returning undisturbed to their original paths. The findings were published online this week by Science.

Light wave basics:

www.yorku.ca/phall/ P1070W05/L11/sec1.html Copyright Pearson Education Inc.

Light can be emitted, absorbed, transmitted or reflected by matter. Metamatter alters the shall we say 'traditional' ray paths!


  Does the speed of light effect what can be 'seen' on the other side? Perhaps the diff is at least detectable.

  Metamaterial blocks visable spectrum, not other parts of the spectrum nor radar or sonar. Still interesting.

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"We shall need compromises in the days ahead, to be sure. But these will be, or should be, compromises of issues, not principles. We can compromise our political positions, but not ourselves. We can resolve the clash of interests without conceding our ideals. And even the necessity for the right kind of compromise does not eliminate the need for those idealists and reformers who keep our compromises moving ahead, who prevent all political situations from meeting the description supplied by Shaw: "smirched with compromise, rotted with opportunism, mildewed by expedience, stretched out of shape with wirepulling and putrefied with permeation.
Compromise need not mean cowardice. .."

John Fitzgerald Kennedy, "Profiles in Courage"


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