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Everyday science

Everyday science

A demon of a puzzle

25 Sep 2021
Taken from the September 2021 issue of Physics World. Members of the Institute of Physics can enjoy the full issue via the Physics World app.

In 1871 James Clerk Maxwell proposed a puzzle now known as “Maxwell’s Demon” in his book Theory of Heat. We celebrate its 150th anniversary in this thermodynamics-themed cryptic crossword compiled by Ian Randall

If you’d like a PDF of the crossword to print out and complete, please click on this download link.

Cryptic crossword grid


1 A limo cat, writhing, is concerned with the smallest matters (8)
5 Robotic prostheses created by bishop from charged integrated circuit with sulphur (7)
9 Trendy machismo, in a tizzy, has energetic focus (14)
12 A Copernican revolution? That’s one in the eye, archdeacon (4)
13 A-level physics comes in form that gives Saturn its place (5)
14 In taking the last of the Rolos, craving leads to rush of power (5)
15 Mr Astaire, doing the twist, blows at a high altitude (9)
16 TV’s O’Connor went around coral island to find origins of radiation (6)
18 Wrapped up man was Marie’s relationship to Ève and Irène (5)
19 Partial fan? British lady adores dear Einstein, initially (5)
20 Maxwell’s establishment part of lovemaking scandal (5)
23 Imperial rival encountered the head of Richard (6)
26 Stiff card is material for passing through grating (9)
27 Satyr, aimless, is skilled outside of the sciences (5)
28 Power supply ultimately charges keen jacuzzi yoga team the wrong way (5)
29 Student paper caught in vortex, amazingly (4)
30 Strongmen, ergo a distorted set of radiographs (14)
31 Saturn’s fourth visitor? SI unit gained when gambling palace loses nothing (7)
32 Maltreats, sounds like the young lady is taking them to court, stupidly (8)


2 Physical quantity locates ancient city in clement clime (11)
3 Old US measure of work is a newly formed gamer term (9)
4 Fossil-fuel preserver found in confused eco store (8)
6 Venerated, without origin, acquired charge (7)

7 Nice rum scrambles one type of code (7)
8 Ideal from Carnot is a penny-farthing (5)
10 Not the first law breaker? At the most, a healthy fiend (8,5)
11 Worshipping as a god has steamy action for getting rid of unwanted liquid (13)
17 From Tesla’s birth state, but later on? You, we hear, go to Prague football team with force (11)
21 Entropy always does this! Clothes before you iron them (9)
22 Ordered structures? Weep, heavenly bodies, as right becomes left (8)
24 League tables wrap can in trashy newspapers (7)
25 Sob, love, for short information? Low-temperature provider (7)
27 Keck greeting fractures a halo (5)

Answers will be published in the October issue of Physics World. Please note that this crossword is just for fun; there are no prizes.

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