Photoelectric Effect

The photoelectric effect, which Einstein explained
as a quantum phenomenon, entails photons
kicking out electrons from the surface of a metal.
The photovoltaic effect entails photons kicking up
electrons into an excited state within the surface of
a semiconductor. Although the two phenomena
share similarities, McEwan might be stretching
things a bit to have his fictional physicist tie them
together in a quantum field theoretic framework,
the Beard–Einstein conflation of the novel.
That stretch aside, the Beard–Einstein conflation is
plausibly invoked in the novel to describe quantum
coherence in photosynthesis. The conflation is
also, plausibly, the theoretical basis of a new and
efficient way to catalytically split water with solar
energy (hence the novel's title).
Given that Beard's life, past and present, occupies
so much of the novel, how convincing a physicist
is he? Before addressing that question, I should
point out that most of the plot's action takes place
after Beard has all but retired from doing research.
McEwan is free therefore to explore his main
character's other qualities, which are mostly
loathsome.
Besides being lazy, Beard is duplicitous, venal,
gluttonous, and philandering. At best he's pitiable;
at worst, despicable. If the novel weren't satirical
and funny, reading about Beard and his exploits
would be trying.
But McEwan does manage to weave in
observations and plot elements that are consistent
with Beard's profession. For example, while an
undergraduate at Oxford, he bones up on the 17th-
century poet John Milton to woo and bed Maisie, a
student of English literature. Smugly, the young
Beard observes that while he could pass off as
literature maven after a month's study, humanities
students could never pass off as physicists no
matter how hard they tried.
If you can stomach a physicist behaving badly,
Solar is well worth reading.