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Banquet Speech. Read David J. Gross's speech at the Nobel Banquet and see the video at http://www.nobel prize.org. Questions
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Banquet Speech
Read David J. Gross's speech at the Nobel Banquet and see the video at http: //www. nobel prize. org.
Your Majesties, Your Royal Highnesses, Ladies and Gentlemen.
For more than 100 years the Nobel Foundation has handed out these generous prizes and hosted these magnificent banquets. All of this was made possible due to the generosity and vision of Alfred Nobel. But can it continue?
To continue having such splendid parties two things are required. First, an inexhaustible supply of money, but also, equally important, an inexhaustible supply of great scientific discoveries.
The first requirement seems to be guaranteed, since the Foundation spends only the interest and wisely invests the capital of Nobel's bequest.
The second requirement might appear harder to satisfy. As knowledge increases, could the pace of scientific discovery slow; as more and more problems are solved?
Fortunately Nature is as generous with its problems as Nobel with his fortune. The more we know, the more aware we are of what we know not. Indeed, the most important product of knowledge is ignorance.
The questions we ask today are more profound and more interesting than those asked years ago when I was a student. Many of those were answered. But back then we did not possess enough knowledge to be intelligently ignorant — and to ask the wonderful questions we ask today.
Some wonder whether some day we will arrive at a theory of everything, and run out of new problems to solve — much as the effort to explore the earth ran out of new continents to explore.
While this is conceivably possible, I am happy to report that there is no evidence that we are running out of our most important resource — ignorance.
How lucky for science.
How lucky for scientists.
And, how lucky for the Nobel Foundation.
(http: www. nobelprize. org/nobel_prizes/physics/laureates/2004/gross-speech. html)
Questions
1) Do you agree that ignorance can be the most important resource as D. J. Gross puts it?
2) Do you believe humanity might one day run out of physics problems to solve?
Unit 5
The Quantum Theory of Optical Coherence
The Nobel Prize in Physics 2005 — Press Release
October 4, 2005
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2005 with one half to Roy J. Glauber, Harvard University, Cambridge, MA, USA, " for his contribution to the quantum theory of optical coherence" and one half jointly to John L. Hall, JILA, University of Colorado and National Institute of Standards and Technology, Boulder, CO, USA, and Theodor W. Hä nsch, Max-Planck-Institut fü r Quantenoptik, Garching and Ludwig-Maximilians-Universitä t, Munich, Germany, " for their contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique".
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Read the text and say in what way Roy J. Glauber, John L. Hall and Theodor W. Hä nsch cast new light on optics.
New light on modern optics
As long as humans have populated the Earth, we have been fascinated by optical phenomena and gradually unravelled the nature of light. This year's Nobel Prize in Physics is awarded to three scientists in the field of optics. Roy Glauber is awarded half of the Prize for his theoretical description of the behaviour of light particles. John Hall and Theodor Hä nsch share the other half of the Prize for their development of laser-based precision spectroscopy, that is, the determination of the colour of the light of atoms and molecules with extreme precision.
Just like radio waves, light is a form of electromagnetic radiation. Maxwell described this in the 1850s. His theory has been utilised in modern communication technology based on transmitters and receivers: mobile telephones, television and radio. If a receiver or a detector is to register light, it must be able to absorb the radiation energy and forward the signal. This energy occurs in packets called quanta and a hundred years ago Einstein was able to show how the absorption of a quantum (a photon) leads to the release of a photoelectron. It is these indirect photoelectrons that are registered in the apparatuses when photons are absorbed.
Thus light exhibits a double nature — it can be considered both as waves and as a stream of particles. Roy Glauber has established the basis of Quantum Optics, in which quantum theory encompasses the field of optics. He could explain the fundamental differences between hot sources of light such as light bulbs, with a mixture of frequencies and phases, and lasers which give a specific frequency and phase.
The important contributions by John Hall and Theodor Hä nsch have made it possible to measure frequencies with an accuracy of fifteen digits. Lasers with extremely sharp colours can now be constructed and with the frequency comb technique precise readings can be made of light of all colours. This technique makes it possible to carry out studies of, for example, the stability of the constants of nature over time and to develop extremely accurate clocks and improved GPS technology.
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