The problem of heat was one that perplexed mid-nineteenth century physicists. One way of understanding it was to think of it as a kind of fluid, ‘caloric’ fluid. I guess that’s where we get the term calorific value. Food equals a certain amount of energy. But in the mid-nineteenth century there was thought to be two kinds of heat: hot and cold. Wrong, of course, but not for the reason we think. James Maxwell and the Austrian physicist Ludwig Boltzmann showed that heat moves in a gradient from hot to cold because atoms when heated oscillate more rapidly and are therefore more likely to collide with each other and create and lose energy. A cold teaspoon placed in a hot cup is therefore more likely to become hot. In quantum physics this is not fixed, but more highly probable than the alternatives, which are also in flux.
Heat changes the past and the future, but where does time go if it cannot flow? The answer is it does not go anywhere. It remains a position, a function, a variable, a location, a quantity. It is coterminous with space, having the same boundaries as space. Space equals time. But it also deictic. Sharing common but not the same boundaries, in the same way that Scotland and England share boundaries. And although you can heat up space, how can you heat up time?
See you next Thursday is dependent on context. Speak so I can hear you. Think of the Big Bang. Time and Space simultaneously radiating in the now. But what is now? A collection of forces interacting and pushing against each other in the Big Bounce and creating the probability of the Big Bang. Reductio ad absurdum. Einstein suggested that the distinction between the past present and future is nothing but a persistent, stubborn illusion.
Contrast with the more familiar idea of the German philosopher Martin Heidegger with the emphasis on ‘dwelling in time’. Physics becomes for some of his more extreme follower a discipline that is incapable of describing reality.
Let us look back and forward to the idea that heat is god. There is only a detectable difference between the past and future and different states when there is a flow of heat. Probability is king. But some of his subjects are subject to revolt.
Quantum gravity is a blurred vision of physics. But Stephen Hawkins has demonstrated that black holes are always ‘hot’. Hot space creates time in flux. The quanta of space, the vibrating ‘molecules’ that heat the surface of the black hole and are heated by the black hole generate change. Time in flux. Flux in time.