The idea that time is an illusion is an old one, predating any Times Square ball drop or champagne celebrations. It reaches back to the days of Heraclitus and Parmenides, pre-Socratic thinkers who are staples of introductory philosophy courses.
Something can be real - actually existing, not merely illusory - and yet not be fundamental. Scientists used to think that heat, for example, was a fluidlike substance called 'caloric' that flowed from hot objects to colder ones.
Claims that some form of consciousness persists after our bodies die and decay into their constituent atoms face one huge, insuperable obstacle: the laws of physics underlying everyday life are completely understood, and there's no way within those laws to allow for the information stored in our brains to persist after we die.
I'm trying to understand cosmology, why the Big Bang had the properties it did. And it's interesting to think that connects directly to our kitchens and how we can make eggs, how we can remember one direction of time, why causes precede effects, why we are born young and grow older. It's all because of entropy increasing.
Naturalism is a counterpart to theism. Theism says there's the physical world and God. Naturalism says there's only the natural world. There are no spirits, no deities, or anything else.
Whenever you say you're a physicist, there's a certain fraction of people who immediately go, 'Oh, I hated physics in high school.' That's because of the terrible influence of high school physics. Because of it, most people think physics is all about inclined planes and force-vector diagrams.
Among advocates for life after death, nobody even tries to sit down and do the hard work of explaining how the basic physics of atoms and electrons would have to be altered in order for this to be true. If we tried, the fundamental absurdity of the task would quickly become evident.
We ought to teach kids more about the Big Bang and entropy and particles. Every high school graduate should know that everything in the universe is made of a handful of particles. That's not a hard thing to know. But that's not what's emphasized.
Even in empty space, time and space still exist.
The fact that you can remember yesterday but not tomorrow is because of entropy. The fact that you're always born young and then you grow older, and not the other way around like Benjamin Button - it's all because of entropy. So I think that entropy is underappreciated as something that has a crucial role in how we go through life.
The arrow of time doesn't move forward forever. There's a phase in the history of the universe where you go from low entropy to high entropy. But then, once you reach the locally maximum entropy you can get to, there's no more arrow of time.
A full understanding of what happens in our everyday lives needs to take into account what happened at the Big Bang. And not only is that intrinsically interesting and just kind of cool to think about, but it's also a mystery that is not given much attention by working scientists; it's a little bit underappreciated.
The fact that the underlying laws of physics are deterministic and impersonal does not mean that at the human level we can't talk about ideas about reasons and goals and purposes and free will.
Science isn't just about solving this or that puzzle. It's about understanding how the world works: the whole world from the vastness of the cosmos to the particularity of an individual human life. It's worth thinking about how all the different ways we have to talk about the world manage to fit together.
I don't want to give advice to people about their religious beliefs, but I do think that it's not smart to bet against the power of science to figure out the natural world. It used to be, a thousand years ago, that if you wanted to explain why the moon moved through the sky, you needed to invoke God.
The particular aspect of time that I'm interested in is the arrow of time: the fact that the past is different from the future. We remember the past but we don't remember the future. There are irreversible processes. There are things that happen, like you turn an egg into an omelet, but you can't turn an omelet into an egg.
We tend to talk about the world in a myriad of ways - a microscopic world of elementary particles, a biological world of organisms and evolution, a social world of morality and meaning. But it's all the same underlying world. That's the underlying theme of 'The Big Picture.'
There's no reason to be agnostic about ideas that are dramatically incompatible with everything we know about modern science.
Naturalism says that we were not put here for any purpose. But that doesn't mean there isn't such thing as purpose. It just means that purpose isn't imposed from outside. We human beings have the creative ability to give our lives purposes and meanings.
Our conviction that green cheese makes up a negligible fraction of the Moon's interior comes not from direct observation but from the gross incompatibility of that idea with other things we think we know.