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10.06.2008 10:56

Conversing with Luminaries of Cosmology: In Lindau, Top Talented Young Scientists Listen to the Echoes of the Early Universe

Christian Rapp Communication and Organisation
Kuratorium für die Tagungen der Nobelpreisträger in Lindau e.V.

    Cosmology - the scientific study of outer space - is a relatively young branch of physics that began to boom after World War II, when rockets and measuring instruments became available to record cosmic rays other than visible light. Since then, it has fundamentally changed our view of the world. When they come to Lindau in early July of this year, up and coming scientists from around the world will have an opportunity to gain a deeper understanding of the significant stages of this development in personal conversations with its protagonists. During the 58th Meeting of Nobel Laureates - this time dedicated to physics - they will, amongst others, meet Riccardo Giacconi and George F. Smoot, who decisively helped to turn the once-speculative cosmology into an exact science.

    Cosmology - the scientific study of outer space - is a relatively young branch of physics that began to boom after World War II, when rockets and measuring instruments became available to record cosmic rays other than visible light. Since then, it has fundamentally changed our view of the world. When they come to Lindau in early July of this year, up and coming scientists from around the world will have an opportunity to gain a deeper understanding of the significant stages of this development in personal conversations with its protagonists. During the 58th Meeting of Nobel Laureates - this time dedicated to physics - they will, amongst others, meet Riccardo Giacconi and George F. Smoot, who decisively helped to turn the once-speculative cosmology into an exact science.

    When Albert Einstein framed modern cosmology with his general theory of relativity in 1915, our universe was considered an unfathomably large yet static extension of space and time, without a beginning and without an end. Under today's Standard Model of cosmology, however, we must assume that our universe emerged around 14 billion years ago from a so-called 'Big Bang' and has been expanding at an increasing velocity every since. Things in outer space are incredibly dynamic, as it became clear after 1962, when Riccardo Giocconi successfully recorded x-rays from outside our solar system. With this, he opened a new window for cosmology. In 1981, Giacconi was appointed founding director of the Space Telescope Science Institute and hence became a driving force for the shuttle launch of the Hubble Space Telescope (http://www.hubblesite.org).

    The space telescope is named after astronomer Edwin Hubble, who laid the foundation for the theory of the 'Big Bang' already in 1929. That year, he demonstrated that the outer galaxies of the universe are drifting apart from each other like dots on the surface of a balloon in the process of being inflated. This expansion, however, did not necessarily permit the conclusion that the universe had originated in a 'Big Bang' - just as plausible was a steady-state scenario in which the universe appeared to observers to remain the same, as would a current flowing by, as it formed new galaxies and stars while the old ones passed out of sight. Both the Big Bang and the Steady State models of the universe found convinced proponents in disagreement with one another, until the tide began to turn in favour of the Big Bang model in 1964. With a discarded radio telescope, the two young American astronomers Penzias and Wilson received background interference from all directions that they were initially unable to explain. The more surprising it was to discover that with this signal they had probably picked up a late echo from the Big Bang, a signal the existence of which other astrophysicists had already predicted.

    This prediction presumed that if the universe had begun with a Big Bang from an infinitely dense and hot singularity, then it must have consisted primarily of perfect radiation. The wavelength of such black body radiation is a function of temperature alone. For the most part, this roaring sea of energy gradually transformed into matter. Yet a remainder of this radiation, dramatically cooled, can still be measured today and bears witness to the beginnings of our world. If this assumption is true, cosmic background radiation cannot be distributed totally equally but must display very tiny, direction-dependent differences in temperature. Otherwise, there would be no way to explain the emergence of clusters of matter such as galaxies from that field of energy. These differences, however, are not observable from the surface of our earth as its atmosphere absorbs too much cosmic radiation.

    To circumvent this, in 1974 the American space authority NASA started its CO(smic) B(ackground) E(xplorer) Project, directed by John Mather and George F. Smoot. In November 1989, the COBE satellite was finally launched into orbit (http://lambda.gsfc.nasa.gov/product/cobe/). Nine minutes later, it sent its first pictures back to earth, providing a precise demonstration of the predicted perfection of the echo of the Big Bang. Charting the COBE pictures, Smoot effectively succeeded in detecting tiny, direction-dependent variations. Aided by these variations, he could identify the coordinates where clusters of matter had begun to develop in the beginning of spacetime. Smoot described the significance of his findings for the biography of our universe 'In human terms, it's like looking at an embryo that's a few hours old",. Generally, the results of NASA's COBE mission are widely regarded as almost irrefutable proof of the Big Bang model. The results of COBE ultimately transformed cosmology into a precise field of science.

    A more detailed version of this press release is available at http://www.lindau-nobel.de (Communications/Press Release).

    _________________________________________

    The annual Meetings of Nobel Laureates in Lindau are organised by the Council for the Meetings of Nobel Laureates in Lindau under the presidency of Countess Sonja Bernadotte (Isle of Mainau). The Foundation Lindau Nobelprizewinners Meetings at Lake Constance, whose Founders´ Assembly includes more than 185 Nobel Laureates, supports the Meetings. The natural-scientific Meetings of Nobel Laureates in Chemistry, Physiology or Medicine and in Physics have been held since 1951. Since 2004, the holders of the Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel, have also held biannual meetings on Lake Constance.


    Weitere Informationen:

    http://www.nobelprize.org
    http://www.aip.org


    Merkmale dieser Pressemitteilung:
    Mathematik, Physik / Astronomie
    überregional
    Buntes aus der Wissenschaft, Forschungs- / Wissenstransfer, Wissenschaftliche Tagungen
    Englisch



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