j. renns

How Einstein’s theory of gravitation experienced a Renaissance after World War II

Journey into the post-war transformation leading to the return of General Relativity within physics

Einstein’s 1915 theory of gravitation, also known as General Relativity, is now considered one of the pillars of modern physics.

It contributes to our understanding of cosmology and of fundamental interactions between particles.

But that was not always the case.

Between the mid-1920s and the mid-1950s, General Relativity underwent a period of stagnation, during which the theory was mostly considered as a stepping-stone for a superior theory.

In a special issue of EPJ H just published, historians of science and physicists actively working on General Relativity and closely related fields share their views on the process, during the post-World War II era, in particular, which saw the “Renaissance” of General Relativity, following progressive transformation of the theory into a bona fidae physics theory.

In this special issue, new insights into the historical process leading to this renaissance point to the extension of the foundation of the original theory, ultimately leading to a global transformation in its character.

Contributions from several experts reveals that the theory of 1915 was insufficient to reach firm conclusions without being complemented by intuitions drawn from the resources of pre-relativistic physics.

Or, in the case of cosmology, the theory needed to be complemented by philosophical considerations that were hardly generalizable to help solve more mundane problems.

As physicist Pascual Jordan puts it, there was a “mismatch between the simplicity of the physical and epistemological foundations and the annoying complexity of the corresponding thicket of formulae.”

A number of contributions in this special issue also explain how the theory underwent a period of successive controversies, leading by the 1960s, to the renaissance of the theory.

Subsequently, it became in the 1970s, an important, empirically well-tested branch of theoretical physics related to the new, successful sub-discipline of relativistic astrophysics.

###

References: Editorial introduction to the special issue “The Renaissance of Einstein’s Theory of Gravitation” edited by A. Blum, D. Giulini, R. Lalli, and J. Renn (2017), European Physical Journal H, DOI 10.1140/epjh/e2017-80023-3

9

We will always be partners.

I love the tender way Philip looks at Shoutarou, trying to comfort him, to assure him it’s okay, and to be strong for them both because he knows Shou’s been agonizing over this. But Philip decided that if he must leave he will do it on his own terms, using what’s left of his life for a meaningful purpose and not just gradually dissolving into nothingness. Having completed that purpose, it’s time to go. And Shoutarou is struggling so hard, refusing to look him in the eye because he knows it’ll be the end of whatever pretense of a “hardboiled” style he has left (though really, Philip’s seen through that a long time ago and it’s part of why he loves him).

7

I estimate Shoutarou’s odds of getting Philip into a tux for their own wedding to be 1:10, though they increase significantly if he can get him interested in the symbolic use of formal wear in ceremonies and other cultural functions blah blah blah good luck Shou.

7

I resisted even getting my hopes up at the green-tinted, apparently disembodied POV shots that start appearing here, because I was super-paranoid about it being just one last twist of the knife. Like, “Why do you keep trying to hurt me more, drama…”

(Also, I like to think that they left out all the green-tinted scenes of Shoutarou sleeping, Shoutarou changing clothes, Shoutarou in the shower… because you know Philip’s peeping in on that. For science.)