A superb video explaining Maxwell’s Demon.

Physics World has chosen The Science Magpie as one of its Top 10 books of 2012!

Here’s what they say:
‘Books of science trivia are a dime a dozen here at Physics World’s reviews desk. Really good books of science trivia aren’t nearly as common. Simon Flynn’s grab-bag of stories from all branches of science exudes enthusiasm, breathing fresh life into a venerable format.’ Find out more about the award here.

It was also reviewed in the latest issue of Physics World: ‘The Science Magpie is an easy and enjoyable read, and it will surely give you a host of new jokes and tales for the pub’.

The word atom comes from the ancient Greek for ‘uncuttable’. The idea of their existence was first proposed by Leucippus of Miletus (fl. 435 BC) and Democritus (fl.410 BC). They believed there were indivisible particles of matter, atoms, that moved around a void, and that it was the different patterns these were arranged in that produced change in the world, which we then perceived.

However, the actual existence of the atom, as opposed to the attitude that it was merely a useful concept, wasn’t accepted until 1905. It was then that Einstein showed, using the relatively new mathematics of statistical mechanics, that atoms were responsible for Brownian motion – the random movement of particles suspended in a liquid named after Robert Brown, who noted the phenomenon over 70 years earlier when observing pollen particles in water.

The following video shows brownian motion being observed fat droplets in milk and the animation in the second video explains further how the random collisions of atoms on a particle (e.g. a pollen grain) produces the subsequently observed zig zag motion. And the hotter the temperature, the faster the motion of the atoms, and the greater the random motion.

First published unsigned in Punch magazine in 1885, May Kendall’s ‘The Lay of the Trilobite’ is an uncomplicated yet hugely entertaining poem that provides an irreverent counterpoint to the various heated debates regarding evolutionary theory going on at the time, particularly between the palaeontologist Richard Owen, founder of the Natural History Museum in London, a vocal opponent of Darwin’s Theory of Natural Selection who believed in the concept of fixed species, and T. H. Huxley, who publicly attacked Owen’s thinking and is specifically named by the Trilobite.

A mountain’s giddy height I sought,
Because I could not find
Sufficient vague and mighty thought
To fill my mighty mind;
And as I wandered ill at ease,
There chanced upon my sight
A native of Silurian seas,
An ancient Trilobite.

So calm, so peacefully he lay,
I watched him even with tears:
I thought of Monads far away
In the forgotten years.
How wonderful it seemed and right,
The providential plan,
That he should be a Trilobite,
And I should be a Man!

And then, quite natural and free
Out of his rocky bed,
That Trilobite he spoke to me
And this is what he said:
‘I don’t know how the thing was done,
Although I cannot doubt it;
But Huxley – he if anyone
Can tell you all about it;

‘How all your faiths are ghosts and dreams,
How in the silent sea
Your ancestors were Monotremes -
Whatever these may be;
How you evolved your shining lights
Of wisdom and perfection
From Jelly-Fish and Trilobites
By Natural Selection.

‘You’ve Kant to make your brains go round,
Hegel you have to clear them,
You’ve Mr Browning to confound,
And Mr Punch to cheer them!
The native of an alien land
You call a man and brother,
And greet with hymn-book in one hand
And pistol in the other!

‘You’ve Politics to make you fight
As if you were possessed:
You’ve cannon and you’ve dynamite
To give the nations rest:
The side that makes the loudest din
Is surest to be right,
And oh, a pretty fix you’re in!’
Remarked the Trilobite.

‘But gentle, stupid, free from woe
I lived among my nation,
I didn’t care – I didn’t know
That I was a Crustacean.*
I didn’t grumble, didn’t steal,
I never took to rhyme:
Salt water was my frugal meal,
And carbonate of lime.’

Reluctantly I turned away,
No other word he said;
An ancient Trilobite, he lay
Within his rocky bed.
I did not answer him, for that
Would have annoyed my pride:
I merely bowed, and raised my hat,
But in my heart I cried: –

‘I wish our brains were not so good,
I wish our skulls were thicker,
I wish that Evolution could
Have stopped a little quicker;
For oh, it was a happy plight,
Of liberty and ease,
To be a simple Trilobite
In the Silurian seas!’

The famous Cavendish Laboratory at the University of Cambridge, home to so many significant scientific discoveries, opened in 1874 after William Cavendish, seventh Duke of Devonshire and Chancellor of the University, gave £6,300 to pay for its construction. This was on the proviso that the university’s colleges funded a connected professorship. The celebrated Scottish physicist James Clerk Maxwell became the laboratory’s inaugural head and, upon his death in 1879, was followed by Lord Rayleigh. In 1884 J J Thompson was appointed Cavendish professor and subsequently founded the Cavendish Physical Society, which would meet regularly to discuss a scientific paper, often, but not always, connected to the speaker and who was often a research student but occasionally a member of staff. Just before Christmas each year, the research students held a dinner, with Thompson among the invites. It was traditional for songs to be sung and many were written specially for it. These were eventually collected together by mathematical physicist A. A. Robb and published as the Post Prandial Proceedings of the Cavendish Society.

The following was sung to the tune of ‘Men of Harlech’ and refers to the Planck Relation E = hv where E is energy, h is Planck’s constant and v (the Greek letter ‘nu’) is frequency.

‘hv’

All black body radiations,
All the spectrum variations,
All atomic oscillations
Vary as “hv.”

Chorus:
Here’s the right relation
Governs radiation,
Here’s the new,
And only true,
Electrodynamical equation;
Never mind your d/dt²,
Ve or half mv²
(If you watch the factor “c²“)
“‘s” equal to “ hv.“

Ultraviolet vibrations,
X and gamma ray pulsations,
Ordinary light sensations
All obey ” hv.”

Even in matters calorific,
Such things as the heat specific
Yield to treatment scientific
If you use ” hv.”

In all questions energetic
Whether static or kinetic,
Or electric, or magnetic,
You must use ” hv.”

There would be a mighty clearance,
We should all be Planck’s adherants,
Were it not that interference
Still defines ” hv.”