Stephen Hawking’s Ph.D. Thesis, “Properties of Expanding Universes,” Now Free to Read/Download Online

Image by NASA, via Flickr Com­mons

Imag­ine being Stephen Hawking’s dis­ser­ta­tion advi­sor? Not that most of us can put our­selves in the shoes of emi­nent Cam­bridge physi­cist Den­nis Scia­ma… but imag­ine a stu­dent suc­ceed­ing so pro­found­ly, after hav­ing over­come such remark­able dif­fi­cul­ty, to become the cel­e­brat­ed Stephen Hawk­ing? One would feel immense­ly proud, I’d guess, and maybe just a lit­tle intim­i­dat­ed. Some grad­u­ate-lev­el pro­fes­sors might even feel threat­ened by such a stu­dent. It’s doubt­ful, how­ev­er, that Sciama—who signed off on Hawking’s the­sis in 1966 and died in 1999—felt this way.

As F.R. Ellis and Roger Pen­rose write, when Hawk­ing announced a sig­nif­i­cant find­ing about black holes in 1974, Scia­ma “quick­ly rec­og­nized the impor­tance… hail­ing it as ini­ti­at­ing a new rev­o­lu­tion in our under­stand­ing.” Despite his por­tray­al by David Thewlis as “a kind of author­i­tar­i­an gate­keep­er” in the Hawk­ing biopic The The­o­ry of Every­thing, Scia­ma “was much more than that pic­ture sug­gests,” writes anoth­er of his high­ly accom­plished mentees, Adri­an Melott; “he was a superb men­tor who brought out the best in his stu­dents.” Ellis and Pen­rose, them­selves esteemed sci­en­tists strong­ly influ­enced by Scia­ma, write of his “aston­ish­ing suc­ces­sion of research stu­dents,” three of whom became fel­lows of the Roy­al Soci­ety.

I men­tion these names because they are just a few of the many peo­ple who inspired, chal­lenged, and guid­ed Hawk­ing, much of whose fame rests on his best­selling pop­u­lar cos­mol­o­gy, A Brief His­to­ry of Time. While he may be talked of as a lone eccen­tric sin­gu­lar­i­ty whose mind oper­ates above our mor­tal plane, like every sci­en­tist, he devel­oped in a com­mu­ni­ty that includes many such minds. The obser­va­tion in no way dimin­ish­es Hawking’s accomplishments–it might, ide­al­ly, spur those of us with an inter­est in his work to look at how it devel­oped in con­ver­sa­tion and debate with oth­ers, like emi­nent Cam­bridge physi­cist Fred Hoyle.

We can begin to do that now by going back to Hawking’s grad­u­ate days and read­ing his doc­tor­al the­sis, which has been made avail­able for free down­load by the Cam­bridge Uni­ver­si­ty Library. “Prop­er­ties of Expand­ing Uni­vers­es” has proven so pop­u­lar that it crashed the library web site, with more than 60,000 views yes­ter­day. By con­trast, “oth­er pop­u­lar the­ses might have 100 views per month,” says Stu­art Roberts, deputy head of research com­mu­ni­ca­tions at Cam­bridge.

In a state­ment accom­pa­ny­ing the dissertation’s release, Hawk­ing mat­ter-of-fact­ly sit­u­ates him­self in a vast com­mu­ni­ty of “great” minds:

By mak­ing my PhD the­sis Open Access, I hope to inspire peo­ple around the world to look up at the stars and not down at their feet; to won­der about our place in the uni­verse and to try and make sense of the cos­mos. Any­one, any­where in the world should have free, unhin­dered access to not just my research, but to the research of every great and enquir­ing mind across the spec­trum of human under­stand­ing.

Should we have such open access, all of us could fol­low the debates across aca­d­e­m­ic projects, learn how the most sophis­ti­cat­ed views of the universe’s nature get for­mu­lat­ed and refined. How­ev­er, we’d prob­a­bly also find that few oth­er physi­cists express them­selves with as much clar­i­ty as Hawk­ing. Whether or not we under­stand his sci­en­tif­ic expla­na­tions, we can under­stand his prose, and his direct­ness of expres­sion has won him mil­lions of read­ers who may have nev­er have oth­er­wise read any the­o­ret­i­cal physics. See the first para­graph of Hawking’s intro­duc­tion below:

The idea that the uni­verse is expand­ing is of recent ori­gin. All the ear­ly cos­molo­gies were essen­tial­ly sta­tion­ary and even Ein­stein whose the­o­ry of rel­a­tiv­i­ty is the basis for almost all mod­ern devel­op­ments in cos­mol­o­gy, found it nat­ur­al to sug­gest a sta­t­ic mod­el of the uni­verse. How­ev­er there is a very grave dif­fi­cul­ty asso­ci­at­ed with a sta­t­ic mod­el such as Ein­stein’s which is sup­posed to have exist­ed for an infi­nite time. For, if the stars had been radi­at­ing ener­gy at their present rates for an infi­nite time, they would have need­ed an infi­nite sup­ply of ener­gy. Fur­ther, the flux of radi­a­tion now would be infi­nite. Alter­na­tive­ly, if they had only a lim­it­ed sup­ply of ener­gy, the whole uni­verse would by now have reached ther­mal equi­lib­ri­um which is cer­tain­ly not the case. This dif­fi­cul­ty was noticed by Old­ers who how­ev­er was not able to sug­gest any solu­tion. The dis­cov­ery of the reces­sion of the neb­u­lae by Hub­ble led to the aban­don­ment of sta­t­ic mod­els in favour of ones which were expand­ing.

Whether the remain­der of “Prop­er­ties of Expand­ing Uni­vers­es” is as read­able may be dif­fi­cult to deter­mine for a lit­tle while. As of the writ­ing of this post, at least, both the orig­i­nal link and a sec­ondary URL host­ing a pho­tographed ver­sion of the doc­u­ment have ground to a halt. (Update: Pages are serv­ing fair­ly well again, at least for now.) No doubt many of the vis­i­tors are physi­cists and grad stu­dents them­selves. But their num­bers may be dwarfed by laypeo­ple eager to see Hawking’s pecu­liar genius first emerge into the world, from a com­mu­ni­ty of sim­i­lar­ly bril­liant cos­mol­o­gists.

Relat­ed Con­tents:

Read John Nash’s Super Short PhD The­sis with 26 Pages & 2 Cita­tions: The Beau­ty of Invent­ing a Field

Stephen Hawking’s Lec­tures on Black Holes Now Ful­ly Ani­mat­ed with Chalk­board Illus­tra­tions

Stephen Hawking’s New Lec­ture, “Do Black Holes Have No Hair?,” Ani­mat­ed with Chalk­board Illus­tra­tions

Read John Nash’s Super Short PhD The­sis with 26 Pages & 2 Cita­tions: The Beau­ty of Invent­ing a Field

The Big Ideas of Stephen Hawk­ing Explained with Sim­ple Ani­ma­tion

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness