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
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
The first part of the article outlines Bohr's complementary way of thinking with which he amongst others approached the solution of atomic events in his three famous articles On the constitution of atoms and molecules from 1913. It also shows Bohr not only as a physicist, but as an interdisciplinary thinker and philanthropist. The second part gives a summary of the conference commemorating the centenar of the Bohr model of the atom, which claims to at least to partially for some gaps in the perception of this remarkable figure., Výklad stability atomu podal Niels Bohr ve svých třech stěžejních článcích nazvaných O konstituci atomů a molekul v roce 1913. V nich jedinečným způsobem aplikoval na Rutherfordův model atomu dosud nespojované předpoklady (klasické předpoklady a Planckovu kvantovou hypotézu nebo Balmerovu-Rydbergovu konstantu). To mu umožnilo podat vysvětlení čárového spektra (nejenom) vodíku a v neposlední řadě ho jeho teorie dovedla až k revolučnímu pojetí struktury molekul. V české odborné a laicky zainteresované veřejnosti tak přetrvává představa Bohra především jako fyzika nebo jen strůjce modelu atomu vodíku. Takový obraz o Bohrovi je velmi zavádějící. Ve fyzice Bohr dosáhl řady dalších významných příspěvků a současně byl interdisciplinárním myslitelem, jenž se zabýval filosofií, psychologií, biologií nebo jazykem. Nárokem konference ke stému výročí Bohrova modelu atomu tak bylo alespoň zčásti zaplnit některá bílá místa ve vnímání této pozoruhodné osobnosti., Patrik Čermák, Filip Grygar., and Obsahuje seznam literatury
The Nobel prize in physics was in 2013 awarded to Belgian theorist François Englert and English theorist Peter W. Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN´s Large Hadron Collider"., Tomáš Blažek., and Obsahuje bibliografii
We summarise the important steps and breakthroughs since the first solar neutrino detection by Raymond Davis, Jr. and the subsequent confusion known as the "solar neutrino puzzle", to the two key experiments (Super-K and SNO) that made it very clear that neutrinos, the lightest and most elusive of leptons, undergo a peculiar quantum-mechanical transformation along the path from their source to the detector. To that end, we attempt to describe the basic experimental techniques that made these discoveries possible as well as the important features of the theoretical picture, which subsequently emerged during the same period. and Michal Malinský.
Družice Suomi-NPP je prototypem nové generace meteorologických družic JPSS. Jejím hlavním přístrojem je VIIRS, navazující na radiometry AVHRR a MODIS družic NOAA/POES, resp. Terra/Aqua. Jeho zcela novou součástí je vysoce citlivý přístroj DNB (Day/Night Band) určený primárně pro noční snímání Země a její atmosféry. Příspěvek dokumentuje citlivost přístroje DNB na několika vybraných příkladech., The Suomi/NPP satellite is a prototype of a new generation of weather satellites, JPSS. Its main instrument is VIIRS, a follow-up instrument of the NOA/POES and Metop AVHRR radiometer, and of the Terra/Aqua MODIS instrument. One of its main advances is a brand new Day/Night Band (DNB), designed primarily for night-time imaging of the Earth and its atmosphere. This short article documents the ultimate DNB low-light sensitivity of several selected cases., Martin Setvák., and Obsahuje seznam literatury
This work summarizes the properties of chosen new scintillation and phosphor materials which appeared in the literature during past ten years and corresponding trends in the research and development in the field of the scintillation materials. The most important applications are mentioned as well as they strongly support research activities in this area., Práce sumarizuje vlastnosti vybraných nových scintilačních a fosforových materiálů, které se objevily v literatuře v posledních deseti letech a související trendy ve výzkumu a vývoji v této oblasti, Jsou zmíněny i nejdůležitější aplikace, které výzkumné aktivity stimulují., Vítězslav Jarý, Martin Nikl., and Obsahuje bibliografii