Physics is...

Questions answered by Andreas Bauch, PTB Working Group "Unit of Time"

1. What were your reasons for studying physics? I had expected that for my studies, and even more my later working life, knowledge, proper judgement, patience and staying power would be necessary, whereas communication, appearance and spontaneity would be of lesser importance. At school I inwardly envied those of my classmates who could speak incessantly without having to say something. I often felt that – before opening my mouth - I first had to think. Today I am somewhat disillusioned.
2. What university did you go to? To the university in Mainz on the beautiful Rhine.
3. Did you know a physical experiment at school which particularly impressed you? What are the physical experiments which impress you? We had an air-cushion path for experiments on linear momentum / elastic and inelastic impact etc. We also let spheres, hollow spheres, cylinders etc. roll on inclined planes and determined the ultimate velocities. We were allowed to lay out and evaluate the experiments ourselves. And in most cases our results agreed with those of the textbook!!
4. Your physical aha-experience? For my thesis I constructed a thermocouple to measure the temperature of a GaAs crystal in its support. The temperature indicated was always too high. This impeded us in our experiment for one year. Then someone had the courage to replace my thermocouple by his own thermocouple which measured correctly. I meanwhile had started work at the PTB to learn how measurements are made. In Mainz they mocked me for a rather long time, but fortunately, the world is forgetful.
5. Do you have a favourite experiment? Every now and then I try to push the shot (7.25 kg) more than 8 m.
6. Are you also interested in a completely different speciality? I was on the point of studying archaeology.
7. What profession did you aim for as a child? Engine driver
8. Have you ever had a chemical kit? No
9. By what do you recognize a physicist? I hope they do not recognize me!! I first of all am a human being, Christian, father and a husband - and then a physicist.
10. Your recommendation for future students of physics? Do not specialize too early, take many subsidiary subjects even if you cannot see the benefit in the short run.
11. Do correct measurements require a healthy amount of ambition? Not more than other activities one wants to handle well and correctly.
12. Those who measure a lot, measure a lot of rubbish... Do you think this saying contains a grain of truth? Sounds funny, but it doesn’t mean a thing to me. It is possible that you lose track when you have floods of measurement data and information at your disposal. Cf. question 22.
13. Do you understand quantum mechanics? “I think I can safely say that nobody today understands quantum mechanics.” (Richard Feynman, The Character of Physical Law 1965). I am not presumptuous...
15. A trip to the moon – would you like it? No
16. Your favourite measuring instrument? An analog volt/ampere/ohm multimeter (see below).
17. Do you master a musical instrument? No, my piano is mastering me... It never plays what I want it to play.
18. What measuring instrument would you least be able to dispense with?My favourite measuring instrument. It helps me to repair defective bicycle lights etc.
19. What measuring instrument is in your opinion useless? A bath water thermometer
22. What is in your opinion most important in a measurement? You must have good knowledge of the measurand (not of the result) and make sure that the boundary conditions allow the desired measurement to be carried out. To establish, characterize and document these boundary conditions often is more difficult than to find the appropriate measuring instrument.
23. Correct measurement – a mechanical art or a science? A little of both
24. Would you tell us three important events of your biography? A carefree childhood (1957 foll.) – I learnt a lot during two years of work on my thesis during my studies of physics (1976-82) (we were still allowed to play and take two years of time) – father of three children, who again and again cause surprise (1986 foll.).
25. Do you think there are things which cannot be measured? In the affirmative, what? Beauty (I suppose “things” need not be taken literally).
26. Did you ever see the primary kilogram in Paris? Yes
27. As you know, the Internet was invented by physicists to communicate in virtual terms. Would you have liked to be among the team of the “first Internet hour?” No
28. Which physicist do you admire? Jens Simon, as he also has a doctorate of German philology.
29. Complete the sentence: “A life without measurements is... unimaginable today.”
31. Do you remember the most important measurement of your life? It was on the 24th of November 1986, when, for the very first time, I weighed a new-born baby.
32. There was a time when certain physical experiments were suddenly regarded as politically undesired. How political can physics be in your opinion? A young physicist once visited me. I had invited him to write a doctoral thesis here. He declined, saying that atomic clocks are needed for warfare – which without any doubt is true. The Global Positioning System, for example, would not work without atomic clocks. I can, however, live and work with this knowledge.
Other fields of physics which influence politics are energy production, energy storage, supervision of disarmament measures – not to mention nuclear physics.
33. Is it possible to still discover something new in the field of physics? As soon as I completely understand what is going on in our atomic clocks, I will change my field of work.
34. Is nature really as physics, biology and chemistry describe it? The question suggests that there is something beyond the scientific description of nature. That is surely true – see question 25.
35. Try to find a definition for coincidence. Coincidence is always involved. And most surely when I lose.