Journal Club – Black Holes Made All The Difference

Article written: 24 Mar , 2012
Updated: 23 Dec , 2015
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According to Wikipedia, a journal club is a group of individuals who meet regularly to critically evaluate recent articles in the scientific literature. And of course, the first rule of Journal Club is… don’t talk about Journal Club.

So, without further ado – today’s article is about how turning complex theory into plain English can lead to advances in science.

Today’s article:
Schutz, B. Thoughts about a conceptual framework for relativistic gravity.

This article is a bit on the philosophical side and involves some debatable historical interpretation. For example, it is claimed that Einstein’s general relativity theory, after an initial buzz in the 1920s, sat in the obscurity of backroom physics through the 1930s and up to the mid 1950s. Indeed, as an example of the maxim that you often have to wait for someone to die before the science can move on, it is claimed that only after Einstein’s death in 1955 did something of a revival take place, which then brought relativity physics back into the mainstream.

The author Bernard Schutz can claim some authority here since his thesis supervisor was Kip Thorne whose thesis supervisor was John A Wheeler. Wheeler, quoting from his Wikipedia write up was an American theoretical physicist who was largely responsible for reviving interest in general relativity in the United States after World War II. And according to Kip Thorne’s Wikipedia write up, Thorne is one of the world’s leading experts on the astrophysical implications of Einstein’s general theory of relativity. Bernard F Schutz’s Wikipedia write up just says he is an American physicist, but give him time.

In the article, Einstein is claimed to be partly responsible for keeping general relativity in the boondocks by dismissing some of its more exciting implications such as black holes and gravitational waves. Instead Einstein doggedly pursued his idea of a unified field theory which led relativity science to an apparent dead end.

Wheeler was at Princeton University at the same time as Einstein and is described as a ‘late collaborator’, although much of his earlier work was in quantum physics and he was closely involved in the Manhattan project.

But Wheeler’s later work and teaching was very focused on the implications of the curvaceous space-time geometry of general relativity, which he communicated via plain English heuristic explanations of some of the wilder implications of that geometry. For example, he was responsible for coining the term black hole as well as the term worm hole. And suddenly general relativity got sexy again. There was an explosion of papers from the 1960s on into the 1990s seeking to grapple with the concept of a black hole – which then reached a fever pitch as astronomical evidence of the existence of black holes began to come in.

Schutz’s essential hypothesis is that it was physicists schooled in quantum mechanics taking a fresh look at relativity theory that made the difference. These were physicists schooled in the approach of we have the math, but what does it mean? Suddenly people like Wheeler were back engaging with Einstein-like Gedanken (thought) experiments. This turned the math into plain-English so that non-relativist physicists suddenly got what it was about – and wanted a piece of the action.

So… comments? Was Einstein inadvertently responsible for delaying the incorporation of relativity into mainstream physics? Or is this article just about a bunch of quantum physicists trying to stake a claim in the development of ‘the other side’ of physics? It’s a story of rivalry, jealousy and curvaceous sexiness – I welcome suggestions about an even more controversial article for the next edition of Journal Club.

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6 Responses

  1. lcrowell says

    Schutz does indicate that World War II “got in the way.” The war had a major impact on the trajectory of physics, and not just gravitation. The war not only further displaced research on general relativity, it also delayed progress in quantum field theory.

    Areas of science become “hip” at various times. During Einstein’s glorious years from 1905 through the 1920s the theory of relativity was developed and benchmarked against some observations. These include computing the perihelion advance of Mercury, gravitational lensing of light around the sun (Eddington 1919), and gravitational redshift. I think the eclipse of general relativity came from quantum mechanics, which had a far larger applicable basis. The domain of possible research was far larger. It was a far more attractive area of research to engage in than relativity.

    Einstein did not like the Schwarzschild singularity. He also did not like the idea of gravity waves. Also Einstein could not tolerate the implications of quantum mechanics. By the 1930s Einstein was relegated to an intellectual cul de sac, and relativity theory followed him there.

    LC

    • Member
      Steve Nerlich says

      Yes, that seems to be the story. Probably a lot more money in quantum research for the applicability reason.

      I don’t think anyone much likes the Schwarzschild singularity then or now. Infinite density in zero volume doesn’t seem likely – although it seems untestable anyway.

      • lcrowell says

        It can be looked at another way, which is the Schwarzschild singularity is a blessing. It points to a very deep question that is much more interesting than what is known.

        We seem to be at a unique stage where these founcational questions can be addressed. There has been a bit of a flowering in astronomy the last 20 years, which should continue for at least another 10 years. Particle physics is in a good position as well. Maybe some of these deep questions can be answered in the next 20 years.

        LC

  2. serve_vaessen says

    Apart from the perihelium advance of Mercury and the bending of starlight by the sun (observed by Eddington in 1919), general relativity seemed to be just theory, until major advances were made in relativistic astrophysiscs in the 1960s and 1970s. The first pulsar was discovered in 1967 and Cygnus X-1 as the first candidate black hole in 1971. I think, those discoveries put general relativity in the frontline. Of course, the spendid work of John Wheeler, ans his catching term black hole, played also a major role in promoting general relativity among a wider audience. But observations showed that general relativity is more than just theory.

  3. newSteveZodiac says

    Theory is building a model of the universe in your head and to get it into our collective heads it needs to be communicated. Because everybody’s heads work differently, new ideas only gain traction when they have a common base of old ones, for example the car started life as literally a horseless carriage because nobody yet had the concept of a car in their heads and the carriage industry couldn’t change overnight just because the IC engine had arrived. Similarly computers have indexes, files and folders because people can relate to them better than the alien concept of delineated non-corporeal objects composed of binary encoded characters.

    I have only a tiny insight into the mathematical logic of Einstein’s theories of space-time but it seems almost inexorable to me so I guess it passed quickly into academic acceptance but the idea base simply wasn’t there and it stayed a horseless carriage. Newton’s laws still worked on a practical level and at the same time Planck’s quantum hypothesis was yielding practical applications and explaining well-observed phenomena, if you like QT was a better material to make carriages from.

    Einstein looked at QT and then spent his time trying to invent a car using the new material at the same time, very difficult when nobody had yet got the idea of the car. Add to this WWII which drove Jewish academics out of Germany and non-Jewish ones to the front. The focus of allied physics was developing an atomic weapon so no wonder it took a while before the people who understood the new materials started using them to make the horseless carriage lower, longer, added a steering wheel and put Einstein’s engine under a hood/bonnet to make a car.

    Personally I hate Einstein’s speed limit. It puts us in a cage in this vast wilderness universe. Although there would be huge problems colliding with just 1 hydrogen atom per cm^3 at multiples of C it somehow seems more surmountable than a wormhole or a warp drive. I look forward to the flying car version, or is that the aeroplane version?

    • Member
      Steve Nerlich says

      It’s not really a speed limit since if you are in the spacecraft travelling at 99.9999%c then time dilation/distance contraction mean you could cross the universe in your lifetime – even though thousands/millions/billions of years pass by outside. Of course the hydrogen atom collision scenario is a major problem. You would need a main deflector.

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