It speaks to the imporÂtance of disÂcovÂerÂies in physics over the past few genÂerÂaÂtions that even the disÂinÂterÂestÂed layÂman has heard of the fieldÂ’s cenÂtral chalÂlenge. In brief, there exist two sepÂaÂrate sysÂtems: genÂerÂal relÂaÂtivÂiÂty, which describes the physics of space, time, and gravÂiÂty, and quanÂtum mechanÂics which describes the physics of funÂdaÂmenÂtal parÂtiÂcles like elecÂtrons and phoÂtons. Each being applicÂaÂble only at its own scale, one would seem to be incomÂpatÂiÂble with the othÂer. What the field needs to bring them togethÂer is kind of a “grand uniÂfied theÂoÂry,” a conÂcept that has long since worked its way into popÂuÂlar culÂture.
In the Big Think video above, physiÂcist Michio Kaku explains this sciÂenÂtifÂic quest for what he calls “the God equaÂtion” in about five minÂutes. Such an equaÂtion “should uniÂfy the basic conÂcepts of physics.” But genÂerÂal relÂaÂtivÂiÂty as conÂceived by Albert EinÂstein is “based on smooth surÂfaces,” while quanÂtum mechanÂics is “based on chopÂping things up into parÂtiÂcles.”
The chalÂlenge of bringÂing the two into conÂcert has attractÂed “the greatÂest minds of the entire human race,” but to no definÂiÂtive avail. At this point, Kaku says, only one conÂcepÂtion “has surÂvived every chalÂlenge: string theÂoÂry, which is what I do for a livÂing” — and which has attained a rather high levÂel of pubÂlic awareÂness, if not necÂesÂsarÂiÂly pubÂlic underÂstandÂing.
Kaku breaks it down as folÂlows: “If you can peer into the heart of an elecÂtron, you would see that it’s a rubÂber band: a tiny, tiny vibratÂing string, very simÂiÂlar to a guiÂtar string. There’s an infiÂnite numÂber of vibraÂtions, and that is why we have subÂatomÂic parÂtiÂcles,” each variÂety of which corÂreÂsponds to a difÂferÂent vibraÂtion. “A simÂple idea that encapÂsuÂlates the entire uniÂverse” — and, cruÂcialÂly, a mathÂeÂmatÂiÂcalÂly conÂsisÂtent one — string theÂoÂry has attractÂed astute proÂpoÂnents and detracÂtors alike, the latÂter objectÂing to its untestaÂbilÂliÂty. But one day, techÂnolÂoÂgy may well advance sufÂfiÂcientÂly to falÂsiÂfy it or not, and if not, the door opens to the posÂsiÂbilÂiÂty of time machines, wormÂholes, parÂalÂlel uniÂversÂes, “things out of The TwiÂlight Zone.” A physiÂcist can dream, can’t he?
For more on this subÂject read Michio Kaku’s book The God EquaÂtion: The Quest for the TheÂoÂry of EveryÂthing.
RelatÂed conÂtent:
Michio Kaku Explains the Physics Behind AbsoluteÂly EveryÂthing
What Is DĂ©jĂ Vu? Michio Kaku WonÂders If It’s TrigÂgered by ParÂalÂlel UniÂversÂes
Based in Seoul, ColÂin Marshall writes and broadÂcasts on cities, lanÂguage, and culÂture. His projects include the SubÂstack newsletÂter Books on Cities and the book The StateÂless City: a Walk through 21st-CenÂtuÂry Los AngeÂles. FolÂlow him on TwitÂter at @colinmarshall or on FaceÂbook.
God EquaÂtion underÂstatÂing Right