Theoretical physics – like sex, but with no need to experiment

November 4, 2013 by Mark Jackson, The Conversation
Solving the universe’s mysteries. Credit: dullhunk

There are not many professions where people routinely ask you to justify your work, but theoretical physics one of them. In the wake of the recent Nobel Prize to Peter Higgs and François Englert for their research on the Higgs Boson, this scrutiny has intensified. Richard Feynman once quipped, "Physics is like sex. Sure, it may give some practical results, but that's not why we do it." I will attempt a more comprehensive answer.

Theoretical physicists construct theories of nature. For a theory to be true it must be both consistent with itself and consistent with nature. The first aspect can be verified with mathematics, the second with experiment. Thus physics is based on a checks-and-balance system between these two approaches. Without theorists, experimentalists would not have anything to test. Without experimentalists, theorists would not have anything to explain. I personally chose theory because experimental physics appeared too difficult.

This process of scientific exploration is like geographical exploration. There is the reward of fame for discovering the new and wonderful balanced against the risk of wasting your time (though physics contains less likelihood of a snakebite). Popular lore can be sometimes dramatically overturned, like the interdiction against sailing too far away, lest you fall off the edge of the world. We now know that the history, composition and future of the universe are vastly different than imagined only a few generations ago.

Explorers of the universe

People easily understand the benefits of geographic exploration: beside the practical benefits of obtaining new resources, there is the joy of discovering what was unknown. In most cases this might be as banal as exploring the woods behind your house but the feeling of discovery is the same. And occasionally one can discover something truly new. Isaac Newton was the first theoretical physicist (although in his own time his profession was called "natural philosophy") and likened his work to "finding a shiny pebble on the beach". In his case, the shiny pebbles formed our basis for understanding nature.

Why do people not universally share this joy of scientific discovery? Probably because the language nature speaks is mathematics - one that most people are not fluent in. Unfamiliarity breeds distrust, and I think this may be the reason society has developed a prejudice against scientists. The "mad" or "evil" scientists are staple archetypes of popular culture, yet the vast majority of physicists I know actively hope that their discoveries will benefit society.

To compound this, I sense that people often consider physics to be mathematical poetry: at best amusing, but at worst a waste of time completely removed from reality. By contrast the work of medical researchers is never questioned since we are all lamentably familiar with disease, illness and death. I believe more people will appreciate physics as they understand today's technology is based on yesterday's theory.

Sometimes an application is immediately obvious: it did not take a leap of the imagination to envisage that Einstein's equation E=mc2 (equating mass with energy) could be, and was, used to produce the weapon of mass destruction that is the atomic bomb. More often, however, the purpose is not apparent at the time of the theoretical breakthrough. "People love chopping wood. In this activity one immediately sees results," commented Einstein.

In translation

In 1850 William Gladstone, then the Chancellor of the Exchqeuer, asked British physicist Michael Faraday what the practical value of electricity was. "One day sir, you may tax it," was Faraday's retort. Electricity has obviously had a major effect on society, but so have the two pillars of modern physics - quantum theory and relativity. While each brilliantly solved problems in their respective domains, neither had any obvious practical application.

In the 1940s Bardeen, Brattain and Shockley developed the "transfer resistor," or transistor. They exploited a basic property of quantum mechanics called "tunneling" wherein electrons can travel to regions where classical physics deems not possible. In the two seconds it took you to read this sentence on your screen, you were benefited by the performance billions of transistors. When theoretical physicists in the early 1900s first realised that position and momentum could not be measured simultaneously they could hardly have forseen the digital technology revolution made possible by transistors.

The other prime example of using purely theoretical physics for something practical is the Global Positioning System (GPS). The GPS configuration consists of 24 satellites in high orbits around the Earth. The timing between your GPS receiver and these satellites can determine your position on the surface of the Earth to within a few meters. To achieve this level of precision, the clock ticks from the satellites must be known to an accuracy of billionths of a second. Einstein's theories of relativity allow us to achieve that high accuracy. If these effects were not properly taken into account, your GPS data would be wrong after only two minutes, and the errors will keep growing.

There are occasionally even unintended practical byproducts. In 1989 physicist Tim Berners-Lee proposed merging the technologies of personal computers, computer networking and hypertext into a powerful and easy to use global information system. The name of this network was the World Wide Web (WWW), and his supervisor's response was, "Vague but exciting." There is a plaque at CERN, Europe's particle-physics lab, at the exact place where Berners-Lee's server stood, a modest acknowledgement to one of the most important achievements in recent history.

Because of its lack of direct application to industry, theoretical physics is often underrepresented in the awarding of government and private grants. Recently there have been positive developments with the introduction of the Kavli Foundation, the Yuri Milner Fundamental Physics Prize Foundation, the Foundational Questions Institute and the Simons Foundation - all of which financially support research in . I hope that other benefactors follow their example and support such investigations - what better publicity than to claim that you sponsored the next Einstein?

Apart from practical applications, there is simple pleasure of understanding how the universe works. Oscar Wilde once poetically observed, "We are all in the gutter, but some of us are looking at the stars." Feynman phrased it differently. Asked by a Swedish encyclopedia for a picture of him playing a drum, to paint a more "human" portrait of the physicist, his reply is legendary:

Theoretical physics is a human endeavour, one of the higher developments of human beings—and this perpetual desire to prove that people who do it are human by showing that they do other things that a few other humans do (like playing bongo drums) is insulting to me. I am human enough to tell you to go to hell.

My favourite audience is young children. They are born theoretical physicists, insisting on repeatedly asking "why?" often to the exasperation of their parents. I have been asked all varieties of questions from children, but not a single one has asked me what the purpose of learning about nature was. There are many educational agencies currently investigating how to instill children with a sense of curiosity, but I think the more accurate question is to ask why children lose their curiosity during their transition into adulthood.

The next time I am asked by anyone what the purpose of is I will reply with the following: maybe my research in theoretical will lead to something useful, and maybe it won't. But comprise the few atoms in the universe that know where they came from.

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3.7 / 5 (7) Nov 04, 2013
Whew. At least you managed to pile all your quackery into just 2 posts huh?

But yeah, I'm often annoyed by theoretical physicists also. Then again, as an experimental physicist, I suppose that's just part of the territory.
1 / 5 (10) Nov 04, 2013
Well physicists are always trying to ketch a peek at nature naked. No one has succeeded yet, so what would happen next is still a virgin field for experimentation. The old Greek story of Orion's fate at seeing Diana in the altogether may be instructive in this regard.
4.5 / 5 (2) Nov 04, 2013
The thing as a theoretical physicist is: You can be spectacularly right or spectacularly wrong (more often that latter than the former). In the first case you'll go down in history - in the second case you'll just get passed by.

As an experimental physicist you're at least assured of getting SOME results that mix with reality and are worth entering in the annals of physics journals (unless you're completely incompetent).

Both types are needed. Without the guys and girls working on pure theory you sometimes don't even know what experiment to devise that could open up wholly new paradigms.

1 / 5 (9) Nov 04, 2013
"Physics is like sex. Sure, it may give some practical results, but that's not why we do it."
@teech2 - where do you see any reference to masturbation? (insert ad hominem reference to the masturbitory experience of teech2)
2.3 / 5 (3) Nov 05, 2013
Teech2, I'd guess that Feynman simply meant that for him, Physics deals with physical relationships in nature whereas Mathematics is a bit abstract in it's purist form. In much the same way, sex has to do with relationships and masturbation is kind of

ofc, any article titled, "Theoretical Physics--like Sex, but with no need to experiment" is bringing masturbation to the fore. Back in Feynman's day, nobody but Feynman talked about masturbation...well, maybe the musical Hair (1968), actually broke the ice...the internet took care of the rest.

Well, going to the last line of the article:
"But theoretical physicists comprise the few atoms in the universe that know where they came from." -- really? It's sort of like a physicist telling an ordinary person, "without the Higgs Field, you wouldn't exist." Forgetting that most humans already understand that gravity made existence as we know it, possible. Please explain how nonlife first turned into life. I must know this!
1 / 5 (10) Nov 06, 2013
The Higgs doesn't exist.
The mass is an electric dipole moment.

Antonio Jose Saraiva

kilogram = Coulomb meter
1 / 5 (3) Nov 09, 2013
It seems to me that Mr. Jackson constructs a straw man which he then rails against – against his own evidence. He accuses all, except himself and a small set of others, of not paying proper homage to theoretical physics. Yet he cites that we are all born physicists who always have to know "why". He also cites research which has been paid for by universal public and private support – some of it massive like CERN, atomic research, and space exploration. Science (real and fiction) is a big percentage popular publishing. And there's
He further claims that his is the only profession that must routinely justify its work. What? We all have to do that every day. But Stephen Hawking, for example, can speculate on multi-universes to explain the anthropic principle on the basis of – well?
not rated yet Nov 10, 2013
Nice little article Mike. Zapper gave it a mention on his blog:

I think though that people have become more suspicious of theoretical physicists because they haven't really delivered anything in recent decades. The world-wide-web isn't the internet, and the Higgs boson isn't E=mc², and so on. I think the tricky thing is how to do something about that. There's quite of lot of "discoveries" lying around like low-hanging fruit IMHO, but most theoretical physicists are too focused on their own particular subfield to see them.

John Duffield
not rated yet Nov 10, 2013
and the Higgs boson isn't E=mc²,

I think you don't get what that discovery means. At all.

The discovery of the Higgs boson/Higgs field puts something on a very solid basis that up to now was always taken on an "it works - but we don't know why it works" basis. This goes especially for anything related to E=mc².

We knew stuff had mass. You could measure its effects all around (from gravity to inertia to mass-energy conversions in chemical or nuclear processes).
But we never knew WHAT mass was. Until last year it was just a label on the order of "here be dragons".

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