Jedrska ura

Natančnost časa postaja bolj in bolj uporabna in pomembna in posledično se rojevajo novi načini merjenja časa. Do danes najbolj natančnih meritev časa in frekvence pridemo s pomočjo atomskih ur. Te so ze tako natančne, da če bi delovale več deset bilijonov let, bi bile imele dane napako manjšo od ene sekunde. Kljub tako veliki natančnosti, bi jih v prihodnosti lahko prekosile nove ure, imeneovane jedrske ure. Med tem ko atomske ure delujejo na podlagi vzbujanja elektronov atomov v višja stanja, bodo jedrkse ure delovale na podlagi vzbujanja atomskega jedra. To je zelo obetavno, saj atomsko jedro okolica ne vpliva tako močno kot na elektrone v atomski ovojnici. Za atomsko uro lahko uporabimo atome različnih elementov, a jedrska ura pa bi lahko delovala le s pomočjo enega izmed vseh 176.000 jedrskih stanj. To stanje je prvo vzbujeno jedrsko stanje $^{229}\mathrm{Th}$. Ampak do prve delujoče jedrske ure je potrebno raziskati še veliko nejasnosti.

Nuclear clock

As time precision becomes more and more useful and important, new ways of time measuring have been born. Today’s most precise time and frequency measurements are performed with atomic clocks. The most precise ones work so well, that if they worked for tens of billions of years, they would be less than a second off. However, in the future they could be even outperformed by the so called nuclear clocks. While the atomic clock is based on the excitation of the electrons in an atom, the nuclear clock would work with excitation of an atomic nucleus which is promising, because the atomic nucleus is less affected by the effects of the surroundings like the electrons in the atomic shell. For atomic clock atoms of different elements can be used, but the nuclear clock could be based only on one of the known 176.000 nuclear levels, on the first excited nuclear state of $^{229}\mathrm{Th}$. But to actually build a working nuclear clock there is still so much left to discover.