I am intimately familiar with the interaction of light with matter as a result of having been an avid Amateur Telescope Maker [geometricvisions.com] and Amateur Astronomer since the tender age of twelve.
This led to my acceptance to study Astronomy at Caltech in the Fall of 1982, where I was privileged to attend a non-credit class called "Physics X" that was taught by The Immortal Richard Feynman. You could ask him any question you wanted - it didn't have to be about Physics even - but the ensuing discussion had to be purely conceptual. Questions that would require Feynmen to work out equations on the chalkboard were not permitted.
One afternoon I pointed out to him that the phenomenon that light slows down as it passes through a medium just had to be wrong. When one examines any medium at a subatomic scale, it is mostly empty vacuum with some rare particles that have all been either proven or are suspected to be geometric points. (While Protons and Neutrons have a non-zero diameter, they are each composed of three quarks, which themselves are thought to be point particles.)
"Surely," I pointed out to Feynman, "When light passes through all this vacuous space inside a piece of glass, it always travels at precisely C! How could Snell's Law" - which yields the angle of refraction when light passes through the surface of a medium - "possibly be correct!"
I knew damn well that Snell's Law was correct, as Snell himself experimentally demonstrated the law hundreds of years ago. While he did not measure what the Speed of Light had to do with refraction, we have been able to measure light's speed for over a century.
Feynman replied that when light passes through matter, the charged particles in that matter oscillate in sympathy with the oscillations of the light's electomagnetic field. But because they are all in a bound state, and because accellerating charged particles causes them to emit light of their own, thereby carrying away energy and so dampening their sympathetic oscillation, the movements of the charged particles in matter is not quite in phase with the waves in the light passing through the medium.
Feynman concluded, "The light emitted by the charge particles in matter interferes with the light passing through the medium" - that is, wave peaks add to wave peaks, and so with troughs, while peaks and troughs together cancel each other - "so that the resulting combination of light waves only appears to move slower than C."
Thus the Photons are always moving at a constant velocity of C, but all the Photons in the medium interact so that passing a Photon through the medium will result in the exit Photon being delayed from the timing you would expect from when the entrance Photon entered the front surface. They key to understanding all this is that the entrance and exit Photons are NOT THE SAME PHOTON!
Feynman discusses this in a really lucid way, with rigorous mathematics, in Volume II of The Feynman Lectures on Physics. Volume II covers Electricity and Magnetism, Volume I covers Classical Mechanics - Newton's Laws of Motion and such - while the third volume does Quantum Mechanics. The set of three is expensive but are easy to read, even if you don't know much Calculus, and would be a good investment for any Slashdotter.
I was mortally embarrased to realize years later that I had asked Feynman a really basic, purely conceptual question whose completely rigorous answer led to him sharing the 1965 Nobel Prize with Tomanaga of Japan! Their Quantum Electrodynamics describes the interaction of light with electric charge with complete precision.
Feynman's formulation uses a conceptual drawing called a Feynman Diagram as a calculational and explanatory device. I don't know how Tomanaga formulated his Quantum Electrodynamics, but my understanding as that at first no one could understand why the two theories seemed quite different but always yielded the same numerical results. Some time later Freeman Dyson - Esther Dyson's father - published a paper that demonstrated that their two theories were in fact equivalent. I expect that it was Dyson's paper that clinched their Nobel.
Everyone who knew anything about Dick Feynman - not just us Tech students, as he was at Cornell before Caltech - considered him a heaven-sent deity because throughout his life he considered it far more important to teach Physics than to understand it. The Feynman Lectures resulted from a year he spent teaching Freshman Physics. Some of his lectures were filmed; I expect you could buy DVDs, or maybe find them on YouTube.
Over the West entrance of the Dabney Student House at Caltech is an elaborate, fantastical sculpture of Heaven. God's face looks just like Feynman's!
Some of the happiest memories of my whole life are of the times I spent not just being taught by Dick Feynman, but getting to know him as a person. Such an opportunity doesn't come to many. For having had that opportunity I am truly priveliged.
Friday, September 30, 2011
Comment on slashdot about speed of light by MichaelCrawford
Wednesday, September 28, 2011
Friday, September 23, 2011
A Retrospective of Woody Allen Surrogates
If you have liked woody allen movies, you will like this
A Retrospective of Woody Allen Surrogates from FilmDrunkDotCom on Vimeo.
Thursday, September 22, 2011
Thin Film Transforms Any Surface Into a Massive Multitouch Screen
It would be good to have both gesture and touch integration for these screens. With larger screens it gets difficult to reach all corners, so a *minority report* style interface and touch interface together could make a great tool.
Comment about how current financial system is being run
In Ireland, there were only around 40 or so company directors amongst all the major bank, company and state boards. Most of these were also businessmen, CEOs, or managers. As you can imagine, nest padding was a primary activity. When the state property agency NAMA was created, one of the first acts of the board was to increase the chairman's salary by 70% [www.rte.ie]. I imagine similar outrages occur in the US.
The proper here isn't "doofus factors" or anything to do with individual boards. The problem is that the entire business and governance culture of the western world is no longer functioning properly. It has become mired in corruption, greed, fraud, and mismanagement. Yet still we tolerate crooks and doofuses because seemingly everyone agrees that this is the best way to run things. Our prevalent financial worldviews are unable to explain or understand why things aren't working anymore.
Personally, I feel that a "financial reformation" is needed in our society. Something literally of the magnitude of the Protestant reformation in the 1500s. We need to turn away from the corrupt established church of business and economics and find new business philosophies. We need to find a system which prevents doofuses, grubbers, and psychopaths from running our companies. We need a system in which shareholders are investors instead of gamblers.
We need a new way of doing business, and even of thinking about and understanding business. Otherwise we'll end up with companies like Yahoo, Microsoft, NASA, and Bank of America being run into the ground by directors, managers,and shareholders who at best have no idea what they're doing, and who at worst will actively destroy the company for personal gain.
Another wonderful comment http://tech.slashdot.org/comments.pl?sid=2433280&cid=37432878
What you have just described is the fundamental career philosophy behind the MBA. To state it another way, the default MBA business strategy is: "Ramp up short-term profitability by whatever means is necessary/convenient, regardless of long-term consequences for the company, because by the time those consequences arise, you will have been hired away to work at a different company, at a higher pay grade, and dealing with those consequences will have become somebody else's problem.
The problem for the Western economy is that, ever since the Reagan administration (or the Thatcher administration, or the Mitterand administration, or ... but you get the picture), MBAs have progressively grown in influence to a position of utterly dominating corporate governance in every country outside of China. It is they who are responsible for exporting the bulk of Western industrial production to developing countries, it is they who were responsible for creating and marketing poisonous mortgage-backed derivative securities (and thereby crashing the global economy - a process that is only now reaching its middle, rather than ending), and it is they who dominate corporate boardrooms.
It's not so much that they are psychopaths. It's that they have been trained to be psychopaths by the most prestigious business schools in the Western world. And this all in the name of delivering maximum value to shareholders.
The problem with the MBA philosophy is that the only shareholders that matter - because they are by far the largest shareholders - are institutional shareholders: insurance companies, pension funds, banks, and so on. And these shareholders' investment portfolios are run by - you guessed it - MBAs, who have absolutely no loyalty to anyone or anything except themselves. They'll kick a fundamentally-sound stock to the curb in a heartbeat, so long as their spreadsheets tell them that a company down the block is offering higher short-term profits, regardless of how unsound that new company's long-term outlook might be, because they don't invest for the long term.
Which, incidentally, is why Wall Street and its fraternal counterparts have been experiencing day-to-day mood swings like a bipolar teenager with PMS. In fact, that phenomenon is a result of the MBA-mediated migration to algorithmically-based automated trading systems, which, by intent completely ignore long-term value in favor of short-term gains produced by, essentially, day-trading on a massive scale.
And, short of outlawing MBAs and hanging all existing holders of the degree, I see absolutely zero chance that this utterly broken system that rewards only MBAs will - or, for that matter, can - change for the better any time in the forseeable future.
Wednesday, September 21, 2011
Tuesday, September 20, 2011
The Art of Corporate Mind Control
Just watched this video, not the best but decent. Corporate world currently controls media and lets us know exactly what they want us to know. This is similar to the religion system we had before, religious institutions controlled the content discussed among people, expressing opinions against the religion was prohibited. All the form of communication we are exposed are designed to lead us into believing something that may not be true, it was religion before, now its corporate world. We just gave control form religion -> govt -> corporates.
There are a lot of scenes from *V for Vendetta*, from one of my favourites.
There are a lot of scenes from *V for Vendetta*, from one of my favourites.
Monday, September 19, 2011
Subscribe to:
Posts (Atom)