Day seventeen of the ‘Blogging from A-Z Challenge’. The letter Q is always one of those difficult ones. What words in the English language could I use to convey something about handedness that begins with a Q? Quixotic perhaps but queer is definitely a not. What about Quidditch? Maybe I could weave some clever reference to Harry Potter into my blog. It turns out that it is not clear which hand he prefers. He writes a question in Tom Riddle’s diary with his right hand yet waves his wand around in his left. It’s a clear case of mixed handedness if ever there was one.
I raced my brain and dug deep into my inner thoughts and recalled something about symmetry and handedness in physics. The word spin springs to mind and so I am going to go with Q for quantum. I’m too far into this piece to regret my decision yet it turns out to be mind-bogglingly complicated. I’m indebted to Markus Ehrenfried for his description.
‘Early models of the atom used to be strongly influenced by our image of the solar system: a massive nucleus in the centre surrounded by electrons which orbit the nucleus like planets revolving around the sun. But apart from circling on their orbits the planets (electrons) have another possible motion: they can rotate around their own axis – exactly like the earth does, travelling around the sun within one year but in addition rotating around its own axis in 24 hours.’
To put it another way as in this analogy our planet has an orbital angular momentum around the sun (or the electron around the nucleus) and in addition a spin angular momentum around its own axis.
If you are still with me spin is not always the same for all sub-atomic particles. With neutrinos the spin is referred to as left-handed as it is always opposite to the linear momentum of the particle. Antineutrinos have a right-handed spin. Unfortunately though this left or right handed description doesn’t work for electrons and again I‘ve had to delve into the science literature. According to Hyperphysics:
‘An electron could have spin to the right and be traveling right and therefore be classified as right-handed. But from the reference frame of someone traveling faster than the electron, its velocity would be to the left, while its spin would be unchanged. This would mean that the electron is a left-handed particle with respect to that reference frame.’
I was hoping that there would be something at the subatomic level that would have helped me to understand handedness within the population and the apparent dominance of right over left. I’ve drawn a blank though either because it does not exist or because I don’t understand it.
I’ll finish instead with a couple of quotes which is perhaps the Q that I should have gone with in the first place:
To be hated cordially, is only a left-handed compliment – Herman Melville.
If the left side of your brain controls the right side of your body, and the right side of your brain controls the left side of your body, then left-handed people must be the only ones in their right minds. – W.C. Fields