“‘So,’ said Hector, ‘does looking at the stars teach us anything about time?’
‘It should perhaps teach us inner peace,’ said Hubert, ‘but, as you know, it doesn’t really.’
They went for a walk along a little path not far from the huge telescope, under a magnificent starry sky which could put you in mind of God. Hector remembered that the philosopher he liked, Pascal, when faced with these same infinitely far-off stars, had said: ‘The silence of these eternal spaces terrifies me.’ And yet Pascal believed in God.
Hubert explained different things to Hector. For a start, everything in the universe was so far away that even at the speed of light it would take for ever and a day to go from one place to another.
‘For example,’ said Hubert, ‘if the sun went out all at once, we wouldn’t even notice until eight minutes later. That’s the time it takes the sun’s light to reach us. And yet it’s the closest star to us!’
‘And what about the others, the ones that are further away?’
‘Some died out millions of years ago,’ said Hubert. ‘But by the time the light reaches us, we see them as they were back then.’
My, my, thought Hector, so we’ve found a way to turn back time.
‘So if you travelled a very long way from earth faster than the speed of light, you’d see earth as it was hundreds or thousands of years ago?’
‘Yes, but that’s impossible. Because you can’t go faster than light. At best, if you could zoom off at the same speed as light, you’d still see the earth exactly as it was when you left it, so you wouldn’t have got much out of going.’
‘Why can’t we go faster than light?’
‘There are several answers to that. We are made of fairly heavy atoms. So we can’t go faster than light, which itself has neither mass nor weight. You could also say that the faster a body goes, the more energy is needed to make it go faster, according to the general theory of relativity. So, when you approach the speed of light, you’d need infinite energy to go faster, and nothing and no one has infinite energy.’”
— François Lelord, Hector and the Search for Lost Time