Energy and Human Ambitions on a Finite Planet, 2021a

facilitating a quick return to the text. Corrections <strong>and</strong> other feedback
can be left at https://tmurphy.physics.ucsd.edu/energy-text/.
A number of the examples (set apart in yellow boxes) are not posed
in the form of a traditional question, but rather appear as a statement
that captures a quantitative instance of the concept at h<strong>and</strong>. From this,
students can construct multiple different questions that omit one piece
of information <strong>and</strong> then solve for it using the remaining numbers. In
this way, the example becomes a versatile guide to underst<strong>and</strong>ing. Note
also the convention that ≈ is used to indicate “quantitatively very close
to,” while ∼ represents a less precise numerical value that might be read
“in the neighborhood of,” or “roughly.”
After the primary presentation of material, an Epilogue attempts to put
the tone of the textbook in context as it relates to the challenges ahead.
Appendices include supplemental information on math, chemistry,
worthy tangents, <strong>and</strong> a partial answer key for problems. The answer key
is constructed to discourage shortcuts. Rather than give direct numerical
answers, for instance, it often provides a range within which the answer
is expected to lie. In this sense, it acts more like an intuition transplant,
guiding more likely correct analysis in a manner closer to the way an
expert operates. 6 This approach allows students to at least catch any
glaring errors in approach, like dividing rather than multiplying, for
instance.
The Bibliography at the end applies to the whole book. Clicking on a
green reference number navigates to the reference entry. Each reference
indicates the (hyperlinked) page or pages on which the reference is cited.
Many of the entries contain hyperlinks to online resources. The ability
to navigate “back” from these explorations is very useful.
6: Experts often have a pretty good sense of
the answer even before a detailed analysis,
which serves as a way to identify possible
mistakes <strong>and</strong> force a closer look.
References often provide convenient links
to data collections in the form of Wikipedia
pages. Primary references are easy enough
to track from there.
A Notation section after the bibliography provides an overview of
physical constants <strong>and</strong> symbols used in the text, unit pre-factors, <strong>and</strong> a
table of Greek letters.
A Glossary provides a collection of important terms encountered in the
text. Hyperlinked words in the text (appearing blue) lead to the glossary,
whose entries are also often internally linked to other glossary items.
Additionally, page numbers where entries appear in the text are linked
to easily navigate to them. The “back” navigation feature is extremely
helpful in this context for returning from a rabbit hole of exploration.
Finally, a full alphabetical Index appears at the end to facilitate finding
information in non-electronic versions of this text.
The graphic below reflects all chapters by page count, 7 suggesting a
few different ways to approach this book. Just reading the “Upshot” for
each chapter, <strong>and</strong> possibly the first few introductory paragraphs for
each will convey a decent overview of the book’s contents. The core
message can also be picked out based on the guide below. The book has a
definite quantitative slant, so it will not be possible to avoid math-laden
7: . . . <strong>and</strong> in some cases singles out individual
sections by size <strong>and</strong> position within the
chapter