A Teaspoon and an Open Mind

By Malcolm Hardman
Reading, UK

As a child I was glued to my chair every Saturday evening for the next episode of Doctor Who on the television. It had everything, drama, suspense, horror, humour and, of course, the strange array of monsters that became its trade mark.

But what of the science of Doctor Who? Until now it's just been speculation and fantasy but now, in his new book out this month, Michael White looks at some of the reality behind the Time Lord's ideas that spanned five decades.

How can you make a working TARDIS? Could Daleks or Cybermen take over the world? Can we travel back and forward in time to anywhere we wanted? Maybe it sounds far-fetched, but White shows us that these flights of fancy are based on genuine theories many of which could be reality sooner than we think.

Many of the ideas in the program are far from being possible; most exist only as ideas, albeit well thought through ones. We first have to understand time before we can build time machines and we are only just starting to understand the mathematical principles behind such matters.

One interesting part that caused me to think regarded time. On a sub-atomic level, most physical processes can be carried out in both temporal directions, so if something happens then the reverse of this process also happens and is equally possible. We don't see that of course, we only see things that happen one way, cars don't un-crash, and cups don't re-form as we drop them on the floor, but why should these sub-atomic particles have all the fun? And if we could find out why then could we not begin to re-do some of these things in the other direction? White introduces us to the important terms of being impossible and just very unlikely, meaning that these things could happen but are just so unlikely that probability states they most probably won't.

It normally boils down to the second law of thermodynamics, which states that "the disorder of system always increases" - put simply, it means that if you want to reform that smashed cup, you'd have to put in more energy than it took for you to smash it, which is just not something that happens naturally. If it does, or if we can make it happen, then we might one day be able to control the environment around us. Maybe then we'll be able to pop out to Galifray for our dinner.