I’ve written a paper in which I put into perspective the media catchphrase “time does not exist”. Below you’ll find the introduction to my paper and a link to the whole thing. Enjoy!
Many popular-science books state that time does not exist, while physics textbooks are usually silent about the nature of time – about what they regard as philosophical questions. But one only has to look up to see that the statement that time does not exist is problematic. We see time all around us: from the rise of the sun to the change of the seasons, and from falling stones to decaying trees. Considering all this, how can one ever argue that time does not exist?
Questions about time
We are looking at the problem from the scientist’s perspective, so we focus on the empirical (that which can be observed). What we observe in the case of falling stones and decaying trees is change, not time itself.
Rather than stating that time does not exist, we address the following two questions:
- Is time more than change?
- Does time have a direction, and, if so, is the direction of time an objective matter?
The setup of my paper is as follows. First, we will discuss Newton’s ideas about time and see how he answers the questions above. In this context we will encounter the ideas of presentism, the direction of time, entropy and probability. After having acquainted ourselves with Newton’s views, we will see how Einstein’s relativity seems to wreak havoc with these ideas – lending credence to the idea of eternalism. In the subsequent chapter about quantum theory we will find, perhaps surprisingly, that the standard interpretation of quantum theory brings us closer to Newton’s view. In a concluding section we’ll briefly discuss the consequences of unifying the two pillars of modern physics: what is the role of time in quantum gravity?