Light Years book review

Light is utterly fascinating. Recently, I've developed the sneaking suspicion that reality is just light. Although physicists talk extensively about subatomic particles such as neutrons, protons, neutrinos, muons, electrons etc, as far as I can tell, none of these subatomic particles can be directly detected or observed. All we ever see are light patterns. Although subatomic particles could still exist, their existence is actually only inferred from light phenomena; it is hypothetical. According to the strict rules of science, the existence of subatomic particles should therefore only regarded as an idea, not as a fact, which is a fascinating idea in itself.

Brian Clegg doesn't mention this idea in his book. Instead, he takes the reader on a historical journey, tracking the development of our understanding of light from Ancient Greece all the way to the latest manipulations of light in the laboratory. It's a fun journey and Clegg writes very well. I'd personally liked to have read about light on a galactic scale more, and the Big Bang. I'd also liked to have seen more diagrams - there are only a smattering of them in the book - and the book sometimes feels like a long string of light (as in potted) descriptions of famous scientists, from Newton to Feynmann, but it's still an enjoyable read. I especially enjoyed Clegg's description of Quantum Electro-Dynamics or QED, the theory that won Feynmann a Nobel prize (pg234 onwards in the book). Richard Feynmann is famous partly for his diagrams that visually describe the physics of quantum interaction.


As Clegg's book succinctly points out, Feynmann's QED produces a new and interesting way to look at the atom. The traditional depiction of the atom is electrons orbiting a nucleus, but this is completely untrue, as the components of an atom aren't 'physical things moving' in the normal sense. Instead, the atom is a quantum pattern of elements. QED shows us that it is more accurate to view the atom as an intense pattern of light paths connecting its constituents. It is this light activity in the atom, according to Feynmann, that prevent the electrons from 'spiralling into the nucleus', attracted by the positive charge of the nucleus's protons.

But if this is true, then there is another way of looking at the atom. If subatomic particles don't truly exist, then atoms are actually intense light patterns whose nodes - the event points connecting those light paths - are being called 'particles' when they are no such thing; they are only quantum connections or nodes in that light pattern. In this way, the idea of particles is purely a mental legacy of Classical Physics. Clegg writes in his book:

"In all of light's behaviour, except for flying along in a straight line, it's interacting with matter. To be specific, it's thanks to a charged particle like an electron that a photon of light begins or ends its life."

But this description can be flipped around. It is just as valid to say that: 'an electron is the name we give to a type of quantum connection or end-event in the light-path pattern.'

I'm going off on a tangent here; apologies! Returning to the book review, I definitely enjoyed Brian Clegg's 'Light Years' and I heartily recommend it.