Thursday, August 17, 2017
The secret behind feather iridescence lies in how tiny structures interfere with light. These structures are fine enough to produce color through the warping of light rather than pigmentation.
Understanding how color works at a structural level could be useful for the development of sensors in medical and security applications.
With all of this in mind, we can expect the world to become a lot more colorful in the next few years.
"We are on the threshold of a new era of color science, and the interdisciplinary nature of this collaborative enterprise holds enormous promise," the authors conclude.
The research is published in Science.
The old textbooks might make handy paperweights...
(Phys.org)—In quantum mechanics, it's impossible to precisely and simultaneously measure the complementary properties (such as the position and momentum) of a quantum state. Now in a new study, physicists have cloned quantum states and demonstrated that, because the clones are entangled, it's possible to precisely and simultaneously measure the complementary properties of the clones. These measurements, in turn, reveal the state of the input quantum system.
More information: G. S. Thekkadath, R. Y. Saaltink, L. Giner, and J. S. Lundeen. "Determining Complementary Properties with Quantum Clones." Physical Review Letters. DOI: 10.1103/PhysRevLett.119.050405, Also at arXiv:1701.04095 [quant-ph]
Tuesday, October 11, 2016
I recently received an email from what sounded like a very bright young person, talking about machine consciousness, qualia, and essentia.
Then that email rather mysteriously disappeared.
So this is a 'message in a bottle,' whereby I hope to reach that individual and ask that they try again.
Saturday, October 01, 2016
Watched this on PBS the other night.
There's nothing here you likely haven't known for a long time.
Except for the fact that they state, quite explicitly, that color is a feature of light itself.
Did our civilization just do a 180 on the subject?
And did no one bother to tell me?
Oooh, that makes me so mad.
Thursday, May 19, 2016
Of the many counterintuitive features of quantum mechanics, perhaps the most challenging to our notions of common sense is that particles do not have locations until they are observed. This is exactly what the standard view of quantum mechanics, often called the Copenhagen interpretation, asks us to believe. Instead of the clear-cut positions and movements of Newtonian physics, we have a cloud of probabilities described by a mathematical structure known as a wave function. The wave function, meanwhile, evolves over time, its evolution governed by precise rules codified in something called the Schrödinger equation. The mathematics are clear enough; the actual whereabouts of particles, less so. Until a particle is observed, an act that causes the wave function to “collapse,” we can say nothing about its location. Albert Einstein, among others, objected to this idea. As his biographer Abraham Pais wrote: “We often discussed his notions on objective reality. I recall that during one walk Einstein suddenly stopped, turned to me and asked whether I really believed that the moon exists only when I look at it.”
But there’s another view — one that’s been around for almost a century — in which particles really do have precise positions at all times. This alternative view, known as pilot-wave theory or Bohmian mechanics, never became as popular as the Copenhagen view, in part because Bohmian mechanics implies that the world must be strange in other ways. In particular, a 1992 study claimed to crystalize certain bizarre consequences of Bohmian mechanics and in doing so deal it a fatal conceptual blow. The authors of that paper concluded that a particle following the laws of Bohmian mechanics would end up taking a trajectory that was so unphysical — even by the warped standards of quantum theory — that they described it as “surreal.”
Nearly a quarter-century later, a group of scientists has carried out an experiment in a Toronto laboratory that aims to test this idea. And if their results, first reported earlier this year, hold up to scrutiny, the Bohmian view of quantum mechanics — less fuzzy but in some ways more strange than the traditional view — may be poised for a comeback.
Disclosure: I've long argued for a similar POV.