You are 'observing' it in the same everyday, trivial sense as you would observe anything in the world. If you start with five atoms, and you hear three CLICKS, then there are two atoms left. Every time a particle decays, the computer goes 'CLICK'. Decays can often be measured with a Geiger-MГјller tube. (The last one is strange, the Boolean algebra article says nothing about quantum.) But I don't think any of these links should be there. Have a nice week-end! Maurice Carbonaro ( talk) 08:24, 20 July 2012 (UTC) Maurice just put a link to observer (quantum physics), and before that (but I deleted them) links to Measurement in quantum mechanics#Philosophical problems of quantum measurements, SchrГ¶dinger's cat, and ']'. Please note that this article has been rated as Start-Class on the project's quality scale and as 'High-importance' on the project's importance scale. I suspect that also recent changes performed by people with 'UNI physics papers' haven't fully understood its relation with quantum physics even if there is a very interesting wikipedia article about various interpretations of quantum mechanics not to mention the minority ones. How the heck do you know that half sample has 'decayed'? You have to measure it! And doing so are you sure that 'the moon will still be there'? Please take a look at SchrГ¶dinger's cat article first. 7 How Does Half-Life Decay Stay Constant?.

5 Move Section - Probabilistic Nature of Half Life.

4 Proposing section on application of half life to chemistry.

3 The acceptance of the Copenhagen interpretation among physicists.

Half life in a sentence