By Kumar David –
“Most theorists working in particle physics are in a state of confusion”
A wonderful thing about science is that the greatest and best take time off to write popular books and articles, conduct seminars, or go on lecture tours to take science to the people, especially school and college kids. Einstein and Edington popularised Relativity from early days. The former’s “Relativity: The Special and General Theory”, was in the words of the author, “intended to give an exact insight into the Theory of Relativity to readers who, from a general scientific and philosophical point of view, are interested in the theory, but not conversant with the mathematical apparatus” and was written in December 1916 just 13 months after presenting General Relativity to that historic meeting of the Prussian Academy in Berlin. From 1920 to 1927 Edington wrote five popular books with titles like “Space, Time and Gravitation”, “Stars and Atoms” and his acclaimed “The Theory of Relativity and its Influence on Scientific Thought”.
More recent was a wonderful series of popular essays in the magazine Natural History, later published as books by W.W. Norton Co. and Penguin Books, by palaeontologist and neo-Darwinian evolutionary biologist the late Stephen Jay Gould, who has done so much to captivate readers to an amazing diversity of topics relating to evolutionary biology, fossils, the panda’s thumb, flamingo’s smile and ‘A Dullard Named Darwin’. He will always be remembered as the stoutest defender since bulldog-Huxley of Darwin and his impeccable methodology.
Quantum physics is more difficult to simplify because its results are hidden in the realms of probability (No one can be sure where a particle is, but there is such and such a probability that it may be in such and such a location!). More confusing is the wave-particle duality; an elementary particle can’t make up its mind; it moves like a wave on a lake or a bullet from a gun, it all depends on when, how and how many of them you look at. Such oddities aside, quantum physicists have brought out hundreds of popular books and videos – from the excellent to the mediocre – to explain concepts, sans mathematics, to non-specialists. “Schrodinger’s Cat” by John Gribbin tops my list of popular quantum books while Hawking’s “Brief History of Time”, a best seller, deals with cosmology (Hawking’s “Theory of Everything” is, comparatively, second class).
The point I am making is that whether it is the physical or the life sciences (I have not given examples from medical science and genetics but very readable non-specialist accounts exist) there has been this fruitful sharing between leading scientists and millions of science interested readers.
Has modern physics flummoxed itself?
The last time the term crisis in physics was used was at the end of the Nineteenth and early Twentieth Century when attempts to gauge the movement of the earth through the ‘celestial aether’ and to measure the speed of light relative to moving bodies confounded everybody. Finally, Hendrik Lorentz got the equations right in the late 1890s, but it was a mathematical gimmick called a Transformation. Einstein in 1905 overthrew the paradigms of classical physics and proposed a new space-time framework (Special Relativity); a new view of space and time which transformed the conceptualisation (meaning) of the Lorentz Transformation. It was a paradigm shift, not a gimmick; a philosophically consistent new physics. The crisis seemed happily resolved.
But soon there were hiccups; the wave-particle duality I mentioned, and quantum uncertainty (Heisenberg says you cannot observe the location and motion of a particle – conjugate quantities – with 100% certainty at the same time; the more precise one measurement, a fundamental law called the Uncertainty Principle says the less certain the other). More recently there has been what I call the subjectivity canard. (I am in good company, Einstein said the same thing; “God does not play dice with the universe”). To put it in extreme solipsist terminology, the canard declares that the material universe exists only if a conscious observer is taking a peek at it; otherwise one can’t be sure it exists at all! Did the dinosaurs exits; does Haley’s comet exist after it goes beyond all possible observation; when did Kepler’s Supernova, first spotted in 1604 but 20,000 light years away, actually explode – only when Kepler looked up? Search me, I don’t know how the solipsists will respond, but it will be eerie and unreal. (If you are a fanatic, ask Gamini Kulatunga; I have but can’t fathom his profundities, or make head or tail of his reference sources). But leave all this to one side; we have managed to get along for some time despite these unresolved conundrums.
But things seem to have gone hugely out of control in the last decade both in particle physics and cosmology. South African born Neil Turok (his parents were white liberation fighter members of the ANC) is a distinguished academic physicist. He has been professor at Princeton and Cambridge, won awards and collaborated with Hawking and Roger Penrose, and is now Director of the Perimeter Institute in Waterloo where Canada hopes to match the world’s best physics research. This is what he says.
- Theoretical physics is at a crossroads right now. In a sense we’ve entered a very deep crisis.
- You may have heard of some of these models. There’ve been grand unified models, there’ve been super-symmetric models, super-string models, loop quantum gravity models. Well, nature turns out to be simpler than all of these models.
- If you ask most theorists working on particle physics, they’re in a state of confusion.
- The extensions of the standard model, like grand unified theories, they were supposed to simplify it. But in fact they made it more complicated.
- The number of parameters in the standard model is about 18. The number in grand unified theories is typically 100. In super-symmetric theories, the minimum is 120. And as you may have heard, string theory seems to predict 10 to the power of 1,000 different possible laws of physics. It’s called the multiverse.
- It’s the ultimate catastrophe: that theoretical physics has led to this crazy situation where the physicists are utterly confused and seem not to have any predictions at all.
- We have to get people to try to find the new principles that will explain the simplicity.
I will not attempt to rephrase, I am not a theoretical physicist, but I will add that a web search threw up opinions sympathetic to Turok’s critique but I could not find a single top ranking scientist rubbishing it. To quote from the May 2014 issue of Scientific American.
“It is not an exaggeration to say that most of the world’s particle physicists believe that supersymmetry must be true—the theory is that compelling. These physicists’ long-term hope has been that the LHC would finally discover these super-partners, providing hard evidence that supersymmetry is a real description of the universe. Indeed, results from the first run of the LHC have ruled out almost all the best-studied versions of supersymmetry. The negative results are beginning to produce if not a full-blown crisis in particle physics, then at least widespread panic”.
Supersymmetry remains experimentally unverified, but physicists hang to it in a desperate attempt to resolve the bewildering confusion of particles and mediate between arrays of incompatible theoretical models. Simply stated the assertion is that a super-partner MUST exist for every known basic particle and force. But the first run of experiments on the $10 billion Large Hardon Collider (LHC) in Geneva, which it was hoped would produce them, drew a blank. No super-partners were found. The physics of the infinitesimally small has been thrown into crisis; physicists panic and hang their heads in confusion.
Trouble at the Big End
Cosmology is the science behind astronomy, the observational side, and considers the really big. Here too advances in recent decades have been spectacular but the deeper they probe the more confusing it gets. Some of it simply flies in the face of stout fellow and good companion of everyday life, common-sense. They tell us that 85% of matter in the universe is Dark Matter which no telescope can see or ordinary bloke like you and I experience. They call it a mysterious form of matter – their words, not mine. But how are they so sure it exists? Well the motion of observable stars and galaxies cannot be fully explained unless something additional, something mysterious, is also pulling. What to do? Hey presto postulate “an ineffable effable, effanineffable, deep and inscrutable singular” matter. The Greeks and the Hindus gave the names of gods to stuff they couldn’t make head of tail of, now physicists call it Dark Matter and Dark Energy; why not lump them together and call it a Dark God?
Dark Matter is inferred from the aforesaid mysterious gravitational effects on visible matter, but it I also inferred from what is known as gravitational lensing. Gravitational lensing is known to laymen as the bending of light by huge masses when it passes by. Light from distant galaxies or pulsars is bent (actually blurred) more than can be accounted for by visible matter on the wayside on the road to here. Something else is doing that extra bit; gravitational lensing is the second piece of evidence to postulate the existence of Dark Matter. It must also be the case that Dark Matter is not uniformly distributed throughout the universe (if so it could have no net effect) but is lumpy, being heaped up in just the places cosmologists need to heaped it up so as to demystify their observations!
The story doesn’t end there; hold your breath! Fully 95% of the mass+energy content of the universe is Dark Stuff; 85% Dark Matter and the other 10% a bloke called Dark Energy. You would have heard of the expanding universe; it’s getting bigger all the time. In the 1990s cosmologists got another shock (they seem to be getting shocks every few decades starting from what Galileo did to the Church) when they discovered that it was expanding faster and faster (accelerating expansion). The way to juggle the equations to get round this distemper was another piece of Black Magic. If a mysterious form of energy with appropriate properties could be conjured up, it could be made to take the blame for the acceleration. Eureka, thus was born Dark Energy! (Cosmologists dispute details; some say the ratio is 68% Dark Matter to 27% Dark Energy. Whatever, they are determined to keep us in the dark).
It gets weirder and weirder; Stephen Hawking has from the grotesque wisdom of his equations now proposed a multiverse; an infinity of parallel universes of which ours is just one. Stout fellow common-sense will scoff, and I ask, at what point does counter intuitiveness demand that we mistrust theoretical extravagances? True, we can’t see electromagnetic waves but every one of us puts a mobile phone to an ear blissfully unschooled in Maxwell’s Equations. True, Pasteur was laughed at for the germ theory; “Whoever saw a germ crawling up the wall!” But still, there are limits aren’t there? Nice topic for a chat over two fingers of single malt.