“But the greatest error of all is mistaking the ultimate end of knowledge. For some men covet knowledge out of a natural curiosity and inquisitive temper; some to entertain the mind with variety and delight; some for ornament and reputation; some for victory and contention; many for lucre and a livelihood; and but few for employing the Divine gift of reason to the use and benefit of mankind.” Francis Bacon: On the Dignity and Advancement of Learning (1605).

Are physicists useful to industry? To clear the decks, it might be pertinent to distinguish between two sorts of physics. There is one sort that might possibly be useful, and another sort – glorious though it may be – that certainly is not. Some 100 years ago, this distinction would have made no sense. Physics was a unity. The results of research into electromagnetism, relativity and quantum processes affected the whole. Out of it was born an understanding of materials, of plasmas, of the atom and its nucleus, and of some esoteric elements of space travel.

One has only to look at present-day information technology (which emerged from semiconductor physics), nuclear technology (atomic and plasma physics) and medical physics to see three of the powerful spin-offs from modern physics. We should also not forget aerospace engineering (fluid mechanics), motor engineering (thermodynamics), and telescopes and cameras (optics), which are all the products of classical physics. All of this – modern plus classical – is “mainstream physics”, and physicists who specialize in mainstream physics are surely going to be useful in industry, aren’t they? At least there is a prima-facie case.

Big science: esoteric and extravagant?

But what about high-energy physics and cosmology? A different case has to be made for the usefulness of physicists in these fields. Undoubtedly fascinating though they are, these topics seem to dwell in a different realm that is esoterically mathematical. In high-energy physics there are quarks, there are gluons, and there is a mathematical structure called “quantum chromodynamics” (or QCD) to describe them. Whatever is discovered in this realm may be fundamental, and even elegant and delightful, but it is almost certainly commercially useless.

Of course, there have been some notable spin-offs from accelerator technology (see Particles for profits Physics World April pp44-45). Hospitals can now buy cyclotrons to make radioisotopes for nuclear medicine. Medical physicists routinely use positron emission tomography, while the defence industry is even using QCD software to determine the best locations to place antennae on ships. And who could imagine a world without the CERN-inspired Web?

But these advances are themselves not high-energy physics and are not why high-energy physics is pursued. Discounting serendipitous spin-offs, particle physics is economically useless. With the cost of experiments rocketing into the stratosphere, the subject is in crisis. And without experiment, the investigation can no longer be physics. Some experiments can be done in astrophysics that bear on cosmology, and – insofar as that is the case – cosmology is physics.

Since space and time, after Einstein, have both condensed into a malleable space-time continuum with properties determined by what Newton knew as gravity, an esoteric activity has focused on the mathematical peculiarities of general relativity. This theory shares with quantum theory the problem that neither appears to be complete.

Theorists in these fields revel in time-travel scenarios in general relativity and in many-worlds extravagances in quantum theory. Cosmologists, latching on to the statistical nature of the world as revealed by quantum theory, invent ensembles of universes. Whatever the status of all this – much of it is applied mathematics bordering on mathematical theology and is certainly distinct from physics as an empirical science – it is impossible to see any material benefit of the kind that Francis Bacon had in mind.

So physicists specializing in these fields are not immediately useful even though their creations are fascinating. Nevertheless, any exposure to physics of whatever sort cannot be bad. There is nothing more intellectually wonderful than physics, and familiarity with the work of genius creates an awareness of the highest standards. So industry need not write off high-energy physicists and cosmologists even if they write off high-energy physics and cosmology.

Expertise and engineering

Given the possibility and will to retrain erstwhile devotees of what might be termed “hyperphysics”, the difference between particle physicists and cosmologists on the one hand and mainstream physicists on the other becomes unimportant. So we come back to the question: are physicists useful to industry? Surely the answer is, of course! The burgeoning fields of optical communications and display technology, to mention but two, certainly need the solid-state and quantum-theoretic expertise that physicists possess.

However, expertise is not enough. It is one thing to carry out theoretical or experimental work to elucidate the physics, it is really quite another to make a device work. To get a device to operate efficiently and economically is engineering. That is to say, it is the deployment of not only knowledge (physics) but also of judgement and intuition, which are essential in the inevitable absence of certain knowledge.

Device engineering is not academic physics. All practical engineering structures – transistors or whatever – are nearly always fiendishly complicated. The basic physics is not usually in doubt. The relevant fundamental equations are in place, but applying them to the problem in hand and obtaining solutions that can be used in practice is rarely straightforward.

Delicate choices of approximations and idealization have to be made. As often as not, it is necessary to resort to intense numerical computation, so theoretical physicists must become number crunchers. Where some details of the physics are unclear, experimental work can attempt to clarify the situation – for example, by illuminating the role of some impurity that it would be nice if it was not there in the first place.

Experimental physics here has to do with the contingent rather than the fundamental. It is rare to encounter new physics – so theorists must develop the art of idealization, and experimentalists must embrace contingency. Being a physicist is just the beginning. Applying physics is the challenge. Physics is simple, engineering physics is not.

Wanted: soft skills

So are physicists useful? Well, they could be. But it does need a phase change. In addition to hard technical competence, there must be an array of “soft” skills. What these are has been defined in the recent report Employers’ Views of Postgraduate Physicists, which the Institute for Employment Studies carried out for the Engineering and Physical Sciences Research Council (see Physics and work Physics World July p15). Creativity is highly desirable, but it is no use inventing something that nobody wants or can afford, so there must be business awareness. Inventing something or getting something useful to work or spotting a possible modification is no good if nobody knows about it, so there must be communication skills along with other desirable skills – flexibility, working in a team, leadership and so on.

Apart from communication skills, very little of this can be usefully taught, so universities should not waste time trying. What can be done will be best left to the employer and osmosis in the workplace. As Wittgenstein once remarked: “What a lot of things a man must do in order for us to say he thinks.” What a lot of things a physicist must do for us to say he is useful.

* Editor’s note: there is still time to enter the Physics World survey What’s your philosophy? (see October p18). Responses can be submitted on line on the Brookhaven National Laboratory’s site at www.bnl.gov/bnlweb/physq