Map of life expectancy at birth from Global Education Project.

Thursday, March 15, 2018

Stephen Hawking

Since this seems to be obituary week, I will take the opportunity of Hawking's death to comment on the relationship between physics (and particularly cosmology) and culture. As physicists have applied the tools of reason to gain understanding of the universe, fundamental knowledge has become further and further divorced from the mainstream culture and the need that ordinary people have to make meaning of the world.

Hawking was famous, and important, mostly as a popularizer. I'm not a physicist so I'm not competent to make a confident evaluation of his contribution. However it seems to me that as a physicist he was one of the leaders who helped advance cosmological theory during his career, but many of his ideas remain speculative and he was not really transformative. As I understand it he never won a Nobel prize because none of this key ideas have been subject to theoretical confirmation.

Nevertheless being the incarnation, for the general public, of the cosmic mysteries, was an important cultural role. Hawking's deep journey into cosmological science left him a fully convinced atheist. It took him a bit of a journey to get there but in 2014 he said:

Before we understand science, it is natural to believe that God created the universe. But now science offers a more convincing explanation. What I meant by 'we would know the mind of God' is, we would know everything that God would know, if there were a God, which there isn't. I'm an atheist. 
The fact is, however, that relatively few people are atheists; and for most of those who are not, the scientific understanding of the cosmos is simply unacceptable. As Steven Weinberg famously wrote, "the more the universe seems comprehensible the more it seems pointless." As he goes on to say in the linked interview:

I think it's been the truth in the past that it was widely hoped that by studying nature we will find the sign of a grand plan, in which human beings play a particularly distinguished starring role. And that has not happened. I think that more and more the picture of nature, the outside world, has been one of an impersonal world governed by mathematical laws that are not particularly concerned with human beings, in which human beings appear as a chance phenomenon, not the goal toward which the universe is directed. And for some this has no effect on their religion. Their religion never looked for any kind of point in nature. For others this is appalling, the idea that all of the stars and galaxies and atoms are going about their business, and it's just by accident that here on this solar system the peculiar chemical properties of DNA acting over billions of years have produced these people who have been able to talk and look around and enjoy life. For some people that picture is antithetical to the view of nature and the world that their religion had given them.

It is not only antithetical to religion, it is also, well, counterintuitive and bizarre. Once Edwin Hubble used a powerful telescope to discover the universe, and discover that it was expanding, people tried conceptually running the tape backward and they got the so-called Big Bang. (There was no bang, of course. I want to call it the Initial Singularity, the IS, but the name is too entrenched now.) By mixing Einstein's theory of gravitation with quantum field theory, and making more and more sophisticated observations of the cosmos using ever more powerful and sophisticated instruments, cosmologists were able to deduce the history of the universe that Hawking discusses (as of its stage of development in 1988) in A Brief History of Time. Then, the accelerating expansion, dark matter, and dark energy had not been discovered, so in a sense we know less than we thought we did.

But all of this means nothing to the average person. It just seems crazy. The universe is 13.8 billion years old (approximately)? It started as an infinitely hot, infinitely dense point and suddenly started expanding and cooling? The earth is 4 1/2 billion years old, and it condensed along with the sun from the remnants of a previous generation of exploded stars? There are 100 billion stars in our galaxy (actually probably a lot more than that) and 100 billion galaxies (ditto). Prove it to me! 

Well, you know, unless you want to take a degree in cosmology you're just going to have to trust us. It seems that many people just don't.

6 comments:

Justin Cohen said...

Reminds me of this classic "Onion" article ... almost 20 years old now!

https://politics.theonion.com/nations-experts-give-up-1819565216

Anonymous said...

Used wisely knowledge is power. But modern science is unsettling, and scary. Many of us, perhaps most, would rather feel safe than in charge.

We need to learn to understand that ignorance of reality can put us in real, scary danger.

Gay Boy Bob said...



The interesting thing about physics is the more that is discovered, the less is really known. The physical universe is a lot weirder than anyone had imagined and as one layer of the onion is peeled away, there's only more layers. Matter and energy seem interchangeable and everything seems a matter of probability rather than objective. Then there's the constants of the universe that are so finely tuned that it's hard to imagine the odds of the universe even existing.

So while Hawking may have been an atheist, other scientists see a different story.

Vera Kistiakowsky (MIT physicist): "The exquisite order displayed by our scientific understanding of the physical world calls for the divine."

Paul Davies (British astrophysicist): "There is for me powerful evidence that there is something going on behind it all....It seems as though somebody has fine-tuned nature's numbers to make the Universe....The impression of design is overwhelming".

Ed Harrison (cosmologist): "Here is the cosmological proof of the existence of God the design argument of Paley updated and refurbished. The fine tuning of the universe provides prima facie evidence of deistic design. Take your choice: blind chance that requires multitudes of universes or design that requires only one.... Many scientists, when they admit their views, incline toward the teleological or design argument."


This last quote is most interesting because the recent popular theory of the multiverse has only come about because of the tremendous improbability of our universe existing and the rejection of God so they had to make something up to explain it.





Cervantes said...

These are what are called Deist arguments. If some sentient entity created the universe, it then withdrew and let the mechanism run on its own. These physicists may have a hard time believing that there wasn't some intelligence behind the initial creation, but they see no evidence of any intervention since. So this has nothing to do with the God concept of any religion.

Mark said...

Sean Carroll (http://www.preposterousuniverse.com/blog/) talks about Hawking's scientific legacy. Carroll is a physicist who has done quite a lot of work in popularizing science. I think you'll find that Hawking's legacy was much greater than as a popularizer.

GBB is completely wrong about physics. Advances in physics do not invalidate past work. Our understanding of the physical world consists of constantly improving approximations. At this point we have a very good understanding of how the universe works. The things that physicists find they misunderstood are very interesting, and many have significant implications for things like the conditions at the big bang, but they don't change most of what we understand about most of the universe.

This is from Carroll's piece on Hawking: "In 1983, Hawking and James Hartle published a paper entitled simply “Wave Function of the Universe.” They proposed a simple procedure from which — in principle! — the state of the entire universe could be calculated. We don’t know whether the Hartle-Hawking wave function is actually the correct description of the universe. Indeed, because we don’t actually have a full theory of quantum gravity, we don’t even know whether their procedure is sensible. But their paper showed that we could talk about the very beginning of the universe in a scientific way ... Simply talking about the origin of the universe is a provocative step. It raises the prospect that science might be able to provide a complete and self-contained description of reality — a prospect that stretches beyond science, into the realms of philosophy and theology."

Most physicists believe that there is no god, or at least no necessity to appeal to a god to explain the universe. One day (I think that day has already come), the only need for a god will be to comfort people who are afraid of the truth.

Gay Boy Bob said...

@Mark

Many, including scientists, don't see science and belief in God as mutually exclusive.
A cosmologist's job is to discover the mechanics of the universe. Belief one way or the other doesn't disqualify or impede anyone from doing that.

Bottom line is you don't have to be an atheist to be a good scientist.