Thursday, 19 March 2015

Not all PhDs are created equal

There appear to be a lot of people, most of them with PhDs, who seem to think that the possession of said PhD endows them with superior intellect, or greater worth. I'll let you in on a little secret though - not all PhDs are created equal. I've never met a PhD candidate yet who hasn't worked their arse off to achieve their PhD, but for an unfortunate number of them, the receipt of the PhD appears to be little more than some kind of long-service award. Working hard as a general factotum, dogsbody and second pair of hands for your professor; undertaking tedious rounds of experiments dictated by your supervisor; writing up the conclusions drawn by your head of department; these are not the qualities that should earn you a PhD. New ideas, interesting research, and most of all thinking should be prerequisites.

You may think that this is sour grapes since I'm merely PhysicsBear and not DrPhysicsBear, but though I'd like to have got a PhD it would only be as a defensive shield against all the academics I work for and with who assume that my lack of PhD makes me somehow lesser. It doesn't take most of them long to realise that they may have assumed wrong.

You may think that I can't possibly know that many people in possession of a PhD who are frankly woefully under-endowed with little grey cells. You'd be wrong. Bear in mind I've been in this job for 16 years, and almost every customer I work with has a PhD as a minimum qualification. I've also interviewed people to come and work for us, and most of them (a) had PhDs and (b) were hopeless.

Oh the tales I could tell... actually, go on then, I will...

Exhibit A

One of our customers, let's call him DrS, has a mass spectrometer. Not altogether surprising, as we sell mass spectrometers. He rather confrontationally accosts one of my colleagues and insists "your instrument is broken!" Being the concerned and diligent people that we are, colleague takes a look:

Colleague: So, what seems to be wrong?
DrS: It's broken. There are all those peaks that shouldn't be there.

Hmmm. Let's pause for a moment there. A mass spectrometer does one thing. It analyses the composition, by mass, of the chemicals that you put in. You get one peak per chemical. Sometimes it can go wrong and you get horrible peak shapes. Sometimes it can go wrong and you have tiddly small peaks. Sometimes it can go wrong and you have no peaks at all. Never can it go wrong and invent peaks out of some kind of malice or twisted sense of humour.

Colleague: Um, let's see, those peaks seem to be at masses, um, 18, 28, 32, 40 and 44.

The astute amongst you, or perhaps just the chemists, will notice that those are the molecular masses of water, nitrogen, oxygen, argon and carbon dioxide. Looks a bit like air that does.

Colleague: So, I'd say you have an air leak
DrS: No, that's not possible. Your instrument is broken.
Colleague: OK, well, this is a mass spectrometer, and the spectrum is showing the presence of air, so I think we have to assume the air's getting in there somehow.

This conversation continues for some time in this vein until one of DrS's colleagues comes over and agrees that it must be an air leak. DrS has a chemistry PhD and works as a researcher in an extremely reputable university.

Exhibit B

This time it's the turn of DrB. DrB has been having persistent trouble with the detection system in his mass spectrometer. He keeps reporting to me that it's not detecting any ions at all. Greatly concerned by this development, I have him return all of the detection equipment to us for me to test. To my surprise, it works perfectly in our lab. I return his equipment to him but he continues to report the same problem. I request that he return the timing electronics and PC so I can check over all the hardware and software that actually gathers the data. That too is fine. As are all the cables and interconnections. Eventually, bewildered and slightly worried, I phone him again.

Me: DrB, we can't find anything wrong here. How certain are you that you're actually generating ions? Do you have any way of independently checking if the ion source is working?
DrB: Oh no, I took the ion source off weeks ago.
Me: Erm, if you don't have an ion source, what were you expecting the detector to detect?
DrB: Oh, I thought it might detect cosmic events or something.

I guess it's worth pointing out at this point that we go to great lengths to make sure our instruments don't detect anything other than the ions generated in the instrument. That's rather the point. DrB has a PhD in chemistry, and again, works at at a very respectable university. And yet he had me spend weeks and weeks trying to debug a non-existent problem.

Exhibit C

We make a piece of portable equipment. When I say portable, I mean it's the size of a small suitcase, battery-powered and weighs about 20kg. One person can carry it around, but they end up quite a tired person quite quickly. And despite being portable it's still a delicate piece of scientific equipment. One of our customers, DrH, wanted to know how robust it was and decided to do a series of experiments to determine how rugged it was, and therefore what improvements he might be able to get us to make to improve its ruggedness. When I say "series of experiments", as it turns out I mean "one experiment". He dropped it from a metre. Onto a concrete floor. It broke. To be honest, we could have told him that without smashing a £30,000 scientific instrument. We'd rather imagined he might start at 10cm and work his way up and then he'd at least have had a couple more data points before trashing the whole thing. But no, this engineering-PhD holding expert just dropped it. From a metre. Onto concrete.

Exhibit D

We needed to employ someone new. We wanted either a physicist with strong electronics skills or an electronics engineer with strong physics skills. Almost everyone who had a CV good enough to even consider inviting for interview had a PhD, and all of them from very good universities. We set them all the same little challenge on a white board to see how they coped with thinking on their feet.

If an ion gun produces 20nA of ion current, all of which consists of singly charged ions, how many ions are being emitted per second? (If you need to know the charge on an electron, we can tell you). 

Now, if that gun is pulsed such that it is only on for 40ns in every 100μs, how many ions are being emitted per second? 

And if the ion gun is scanning over a 100μm x 100μm square, what's the dose rate in ions/s/cm2?

Now, I'm happy to accept that not everyone reading this will be able to do that calculation, but it should, quite frankly, be a walk in the park for any science student, never mind someone with a PhD in physics or electronics. The biggest challenge is in handling exponents properly. Even taking into account interview nerves does not excuse the number of candidates who responded "I'm sure I've known this once, but I'd have to look it up" or variations upon that theme. No! Don't look it up, use your bloody brain and think about what current is and what ions are.

The only person to successfully undertake that calculation is now my colleague. Like me, he does not have a PhD.

The prosecution rests its case.


I am only talking about science PhDs here, who knows what those weirdos over in the humanities get up to.

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