Kolláth Zoltán
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Előadó
Több nagy szakmai szervezet javaslatára a 2005-ös évet - Einstein "nagy évének" századik évfordulóját - az ENSZ közgyűlése a Fizika Nemzetközi Évévé nyilvánította. A Fizika Évének egyik fő célja az, hogy hozzájáruljon a fizika és szélesebb értelemben a természettudományok társadalmi elfogadottságának, presztízsének javításához. Ezzel összhangban az előadásban megvizsgáljuk azt, hogy hogyan hatott a fizika a társadalom és kultúra fejlődésére.
The lecture addresses the effect of physics on the development of society and culture. This effect can be traced in two areas. Firstly, perhaps most importantly, yet less tangibly, is the decisive influence it has played on the development of the way we think. The lecture demonstrates this by reviewing the basic characteristics of physical thinking and gives examples of their presence in our everyday apparatus. The other key area the examined in the lecture is, modeling, the art of physics. The genius of those who have created something great in the field of physics lay in their recognition of the insufficient nature of a habitual model and proceed to create a new one. The correctness of modelling influences the resolution of even the simplest problem. Physical models have to be experimentally tested. The cornerstone of experiment is the accuracy of measurement - numerous breathtaking examples can be cited to demonstrate how measurement accuracy has revolutionized science and may even transform everyday life.
A csillagok óriási gázgömbjeiben hanghullámok terjedhetnek. Ezek a rezgések akkorák lehetnek, hogy a csillagok fényének változásaként érzékelhetők, így a csillagbelső hangjait "halljuk". A csillagok hangjai alapján megismerhetjük belső szerkezetüket és működésüket. A csillagrezgések külön érdekessége kapcsolatuk az akusztikus hangszerek fizikájával. A változócsillagok akár a kortárs szférák zenéjének a zenekarát is alkothatják.
Just as in the air, sound waves can travel in the huge gas spheres of stars. For a certain group of the stars, there exists a generating mechanism by which these vibrations become permanent. This pulsation can be registered from the Earth as a change in light. From the study of changing stars their inner sounds can be reconstructed. The use of seismology or ultrasound in medical diagnostics demonstrates convincingly the theory that we may map the inside of the matter examined if we pick up the waves travelling in it, and based on their characteristics we can form a picture of the medium they travel in. That is why the sounds of stars and the study of the processes in them are so important. The conditions existing in the Sun and stars cannot be recreated in a laboratory on the Earth. The study of the inner functioning of stars can reveal to us the future of our planet and the Sun. It is important that the study of certain changing stars can also help in specifying the distance scale used to measure the Universe. We cannot hear the sound of stars directly. While the sound does not travel in the interstellar space devoid of air, these sounds are much deeper than the perceptive range of a human ear. Speeding up the data obtained from observations and models can make these distant infra sounds audible. The music of the stars is varied. We can hear many interesting sounds from the simple humming sound to noise-like, strange, polyphonic booming. The beauty of the starry sky can perhaps be reflected in the music of the stars.
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Előadó
Technikai civilizációnkban egyre kifinomultabb eszközöket használunk. Az ezeket felépítő anyagok tulajdonságait egyre pontosabban kell ismerni, és képesnek kell lenni arra, hogy e tulajdonságokat az igényekhez igazítsuk. A tulajdonságokat meghatározza az alkotó atomok milyensége és térbeli rendje, azaz atomi szerkezetük, ezért ennek pontos ismerete elengedhetetlen ahhoz, hogy megbízható gépkocsikat, elektronikus eszközöket vagy éppen orvosságokat állítsunk elő. Az előadás bemutatja a röntgensugárzással való atomi szerkezet-meghatározás alapelveit, nehézségeit, és kitérünk a jövőbeli lehetőségekre is.
Increasingly sophisticated tools are used in our technical civilisation. We need to know more about the characteristics of the matter these tools are constructed from and be able to adjust these characteristics to our needs. Since the characteristics are mainly determined by the quality and particular arrangement of constituent atoms, i.e. the atomic structure, a precise knowledge of these is indispensable to the production of reliable and appropriate tools for various applications. There are several techniques to determine atomic structure, the lecture presents the principles, existing and future difficulties of the most widely spread: the x-ray measurement technique. We learn why waves are suitable for measuring atomic level distances, how to produce x-rays for measurement (traditional x-ray tube or a synchrotron) and how the structure is actually defined by x-ray. We also learn about new methods developed by researchers to resolve the theoretical and practical problems arising in the x-ray measurement technique such as the development of x-ray free electron lasers, fourth generation x-ray sources and the x-ray holography technique. The aim of the research into the structure of matter is to obtain qualitatively new information and to understand how nature works.