I ask some of the stars – the audience celebrities – how much of Brian Cox's A Night With the Stars (BBC2, Sunday) they understood. None, but this was due to Prof Cox's strong northern accent, says Paul Foot, who's a comedian. Nine hundred percent, says Charlie Brooker, who's a liar. Maybe 10%, replies Sarah Millican, but she still weirdly enjoyed it. Good question, says Al Murray (thank you, Al). At the time it felt like a lot, he goes on, but it's faded fast.
Some of the stars I ask (via Twitter) don't even get back to me. So rude – James May, Simon Pegg, Dr Christian off Embarrassing Bodies, Jonathan Ross. Who the hell do you think you are? Well it's pretty clear from the show that Ross doesn't understand a word. "I have no idea what you're doing to me," he says miserably, standing by a blackboard which is covered in bewildering calculations. "This is the worst thing that's happened to me as an adult."
If it wasn't for Ross's self-deprecating good humour, it might be a bit awkward. I think sometimes people who get complicated maths and physics don't really get how hard it is for those of us who don't really get it.
The calculation has something to do with the time you'd have to wait to have a reasonable chance that a diamond will jump out of a box. And the answer is enormous: 3 x 1029 seconds. Or 600bn times the current age of the universe. Prof Cox has done it again, come up with another staggeringly huge number, to leave us gasping with awe, even if a lot of us don't really understand what it means. Well, what it means – I think – is that the diamond's not going to jump anywhere. "I could have told you that's not going to happen without any of this," says Ross. Perhaps then we have some kind of innate subconscious built-in understanding of quantum theory. That's what this is – celebrity quantum mechanics.
I'd put myself round about Millican's 10% mark. I'm fine with the waves, and the double slit experiment she helps with, and even the emptiness of atoms. But then Coxy takes it one step beyond that, comes up with his enormous numbers and covers his board with Heisenberg's Uncertainty principle and what have you (if Heisenberg wasn't sure, how the hell are we supposed to be?). My brain looks for that extra gear needed to keep up, and it's simply not there. Once you've lost him, that's it, he's gone. And you're left with the jokes of Ross and Millican to hang on to. Which, it must be said, are much better than Prof Cox's. Hey, people end up doing what they're good at. That's reassuring.
I briefly re-engage, at the mention of white dwarves – very dense stars. I remember them from Cox's last series. He loves his white dwarves. No sign of Warwick Davis in the audience – they missed a trick there. Or Jon Snow. They could have turned it into a nice festive celebrity Christmas panto. Maybe with Professor Heinz Wolff too ... no, I'm wandering again.
Otherwise Sunday was a day of undemanding, mediocre, nostalgic, sentimental family drama. Just Henry (ITV1) was probably the hardest to sit through, as it very quickly became clear where it was going to end up two hours down the line. All Creatures Great and Small prequel Young James Herriot (BBC1) was witless and unlovely, a drab little film (actually a three-part series over consecutive nights) that convinced only that some things are best left alone.
Lost Christmas (BBC1), a modern-day fairy tale, was probably the pick of the bunch. But perhaps also the most disappointing because this is not Eddie Izzard at his enigmatic best. He plays a kind of angel character, who can find what's lost and puts this power to good use, to change the past and to right wrongs.
There was a worthiness, almost a preachiness, about it. The incessant, meandering piano score was intrusive to the point that I wanted to scream. And I was cross about how the fireman walked over the ice, to try to rescue the little girl. No fireman would do that, walking along on two feet. He'd lie down, put a ladder down probably, spread the load. Physics, innit?
