The neutron time-of-flight spectrometer (NEAT) at Helmholtz-Zentrum Berlin has a long history of successful application for studying dynamics and function over very broad time and space domains ranging from 10-14 to 10-10 seconds and from 0.05 up to approximately 5 nanometres, respectively. Started originally in 1995 as NEAT I, NEAT II has been fully rebuilt in order to address the needs of the user community for more powerful instruments. From the end of January 2017 researchers from all over the world will be able to investigate the structure and dynamics of substances, including under extreme conditions., Veronika Grzimek, Gerrit Günther, Margarita Russina:., and Obsahuje seznam literatury
Didaktika je teoretická disciplína, která se zabývá vzděláváním, formami, postupy a cíli vyučování. Stručně řečeno, je to teorie vyučování. Didaktika fyziky je tedy nepochybně teorií vyučování fyzice. Návodům "jak učit fyziku", tj. jak přistupovat k výkladu daného fyzikálního tématu či konkrétního problému, musí předcházet zásadní požadavek fyzikální správnosti. Ten není v didaktických textech nikdy explicitně uváděn. Proč taky? Je přece tak samozřejmý, že zmínka o něm by mohla působit až urážlivě. Praxe však ukazuje, že výukové a didaktické texty mohou mít k fyzikální správnosti i dost daleko. Jedním z doslova vousatých problémů, k nimž se tato negativní charakteristika hodí, je jednoduchý problém z mechaniky - řešení pohybu matematického kyvadla, jak uvidíme v tomto článku., Jana Musilová., and Obsahuje bibliografii
In this article basic concepts concerning "uncertainty" and their related topics are presented, explained using examples and discussed. Namely, the concept of "true value" underwent a significant evolution from the so called "Error approach" to the "Uncertainty approach". The concept of quantity value itself is consistent with the concept of uncertainty, rather than "exact value" presented by one exact real number. A particular schism with previous Czech terminology has been solved and some general rules for terminology are stated. This paper was supported by the Czech Ministry of Education, Grand agency INGO II, project LG13026. and Jan Obrdržálek.
Nekonečno ve fyzice občas vystupuje, ačkoli se přímo nejeví - není jevem. Jeho existence závisí na použitých matematicky formulovaných fyzikálních zákonech, tedy idealizovaných modelech, pomůckách k pochopení. Tyto "pomůcky" byly odvozeny ze zkušností s konečným světem a jejich rozšíření na nekonečno je riskantním podnikem. Je tedy nekonečno pojmem ontologickým, vyjadřuje něco skutečně jsoucího?, Infinity plays some role in physics although it is not a phenomenon, so it is not directly apparent in physical world. Its existence depends on our idealised mathematically formulated models, hypotheses, theories. i.e. on our instruments for understanding. These instruments were derived from our experience with a finite, limited world. Their extension to infinity is therefore a risky business. So, is infinity an ontological concept, does infinity exist in reality?, Peter Zamarovský., and Obsahuje bibliografii
O neúspěšných kandidátech na Nobelovu cenu za fyziku (NCF) v letech 1901-1956 byl publikován článek v roce 2008 [1]. Zpřístupněním materiálů Nobelova archivu ve Stockholmu o NCF do roku 1965 lze tudíž referovat o kandidátech NCF z let 1951-1965, což je obsahem tohoto příspěvku., Six unsuccessful candidates, i. e., G. E. Uhlenbeck, S. A. Goudsmit, G. P. S. Occhialini, B. B. Rossi, B. F. Lyot and G. I. Taylor, nominated for the Nobel Prize in Physics from 1951 to 1965, are briefly introduced in this article. The number of nominations was chosen as a criterion of their selection. All the above mentioned researchers were outstanding physicist with numerous great scientific achievements. It clearly indicates, that also other factors than just a scientific excellence influence winning the Nobel Prize., Jiří Jindra., and Obsahuje bibliografii
The nuclear fusion processes that power the Sun take place at such high temperatures that the nuclei of atoms are able to fuse together, a process that results in the creation of very large numbers of fundamental particles called neutrinos. Neutrinos only interact through the weak interaction and gravity and therefore can penetrate out from the core of the Sun and through the Earth with little or no interaction. It is these neutrinos from the Sun that are the subject of our measurements with the Sudbury Neutrino Observatory (SNO), 2 km underground in a mine near Sudbury, Canada. With the use of heavy water as a central element in the design of SNO it was possible to determine clearly that electron neutrinos change to one of the other active flavors before reaching our detector, a property that requires that they have a mass greater than zero. Both of these fundamental neutrino properties are beyond the predictions of the Standard Model for elementary particles. Extensions of the Standard Model to include these neutrino properties can give us a more complete understanding of our Universe at a very basic level., Arthur B. McDonald ; přeložil Ivan Gregora., and Obsahuje bibliografii
V článku názorně představujeme základy fyziky neviditelného pláště, která je založena na tzv. transformační optice., Tomáš Tyc, Ulf Leonhardt., and Obsahuje seznam literatury
The Moon is our nearest celestial body, small variations of its motion are easy to observe. Ptolemy described the ecliptic longitude inequality in lunar motion, now known as the evection. From Ptolemy to the time of Newton the motion of the Moon was determined using kinematic models. The first qualitative dynamic model was published in Principia, where Newton showed that evection is a periodic inequality caused by the attraction of the Sun., Vladimír Štefl., and Obsahuje seznam literatury