Page 39 of Who’s That Girl?

‘I said, “I don’t care if it’s made of crushed pearls from the Adriatic—”’

“No, not that bit,’ I say quickly.

Beatrice frowns. ‘Gosh, I can’t remember.’

‘You said something about being twenty-one again,’ I prompt, my stomach fluttering.

‘Oh, yes, I was talking about time travel.’ She nods matter-of-factly. Putting the products back in the bag, she takes a swig of champagne. ‘Though strictly speaking if you were to travel back through the frontiers of time, you wouldn’t look like you were twenty-one; you’d meet yourself when you were twenty-one.’

I suddenly feel really light-headed, dizzy almost.

‘But you know Stephen Hawking once said time travel isn’t possible,’ she continues, and then laughs. ‘Otherwise we’d all be overrun by tourists from the future.’

‘Well, of course it’s not possible,’ I scoff, quickly recovering. It must be the champagne, I tell myself, using a pamphlet to fan myself. And it is really stuffy in here.

‘However, the theory of general relativity does suggest scientific grounds for thinking time travel could be possible in certain unusual scenarios,’ she adds as an afterthought.

I stare at her in disbelief. ‘What? You’re saying you believe in time travel? You’re joking, right?’

‘Actually, no, I’m not joking,’ she refutes stiffly, pursing her lips. ‘According to the rules of physics, there are several ways it could be theoretically feasible. For example, there are some quantum physicists who believe every historical event spawns a new universe for every possible outcome, resulting in a number of alternate histories.’ She pauses to take a swig of champagne. ‘This is most likely based on the many-worlds interpretation of quantum mechanics formulated by the physicist Hugh Everett in 1957, an alternative to the Copenhagen interpretation originally formulated by Niels Bohr and Werner Heisenberg around 1927.’

Er, hello?

‘Can you say that again, but in English this time?’ I ask, completely lost.

‘Think of it like this.’ Putting down her champagne glass, she reaches over to a passing waitress. ‘Excuse me.’ She smiles, grabbing a handful of mini-quiches, before turning back to me and spreading out her napkin on a nearby table. ‘Rather than a universe,’ she explains, placing a mini-quiche in the middle, ‘it’s a multiverse.’ She continues dotting several more mini-quiches around it. ‘And together these multiverses comprise all of physical reality. The different universes within a multiverse are called parallel universes.’ She picks up a mini-quiche and waves it at me. ‘Imagine this is a parallel universe,’ she suggests, her face serious.

‘Um … OK.’ I nod dubiously.

‘It’s existing at the same time as all these other parallel universes.’ She gestures to all the other mini-quiches. ‘And you can travel between them, see?’

I stare, bewildered, at the mini-quiches, trying to grapple with the information. For someone who dropped physics in favour of creative writing it’s all rather confusing. Actually, make that very confusing.

‘But then of course there’s the other theories that include travelling faster than the speed of light, moving large amounts of physical matter, which releases energy and can cause a crack in time, or the use of cosmic strings or traversable wormholes,’ she says nonchalantly, helping herself to a parallel universe. Sorry, I mean a mini-quiche.

‘A wormhole?’ I repeat, my mouth twitching.

Well, I’m sorry, but I can’t take this seriously. What next? Dr Who’s Tardis?

‘You know, like a portal.’ She shrugs. ‘Or some kind of tunnel that allows you to travel from one time’ – with her finger she traces a line across the napkin – ‘to another.’

Suddenly I get that weird fluttering feeling again in my stomach and a cog in my brain turns. No, but that’s just crazy, I tell myself firmly, dismissing the thought before it’s even fully formed. In fact it’s more than crazy. It’s totally ludicrous.

‘I know. Even I don’t understand it properly,’ she soothes, misinterpreting my silence and patting my arm in consolation. ‘And if I try to explain it in more detail, I’m afraid your head will explode, or implode, depending on what universe we are currently in and the particular wave-function collapse laws,’ she adds, frowning. ‘Saying that, I loved Back to the Future, didn’t you?’ Draining her glass, she smiles brightly. ‘Another glass of bubbly?’

Chapter Twelve

Making my excuses, I leave Beatrice drinking champagne and sneak out of the launch party early. I drive home feeling unsettled, like on a hot summer’s day, just before a storm, when the air gets all charged and seems to prickle with electricity and anticipation, and you’re filled with a strange mixture of excitement and apprehension, knowing something is going to happen. Waiting. Watching. Wondering.

Which is ridiculous, as nothing is going to happen, I think sharply. Nothing at all.

It’s another warm evening and as usual the rush-hour is in full swing. Motorists with their windows wound down and elbows sticking out jostle for every inch of tarmac, while on the pavements pedestrians hurry and scurry like worker ants towards the tube. Following the signs for the diversion, I turn on the radio. A DJ’s chirpy banter wafts out of my speakers, filling the space around me with jokes and jingles and call-ins, and I listen, glad of the distraction.

For about thirty seconds.

Then before I know it my mind is wandering back to the launch like a guest reluctant to leave, sidling over to my earlier conversation with Beatrice. Her words start playing in my head: ‘… be possible in certain unusual scenarios … parallel universes … moving large amounts of physical matter … tunnel that allows you to travel from one time to another’.

My mind flicks back to yesterday – driving past the diggers moving all that earth, being diverted, turning down that side street and going under the underpass, which I suppose is sort of like a tunnel …