How Designing Buildings Upside-Down Revolutionized Architecture, Making Possible St. Paul’s Cathedral, Sagrada Família & More

in Architecture, History, Physics | November 12th, 2024

For 142 years now, Sagra­da Família has been grow­ing toward the sky. Or at least that’s what it seems to be doing, as its ongo­ing con­struc­tion real­izes ever more ful­ly a host of forms that look and feel not quite of this earth. It makes a kind of sense to learn that, in design­ing the cathe­dral that would remain a work in progress near­ly a cen­tu­ry after his death, Antoni Gaudí built a mod­el upside-down, mak­ing use of grav­i­ty in the oppo­site way to which we nor­mal­ly think of it as act­ing on a build­ing. But as archi­tec­ture YouTu­ber Stew­art Hicks explains in the video above, Gaudí was hard­ly the first to use that tech­nique.

Take St. Paul’s Cathe­dral, which Christo­pher Wren decid­ed to make the tallest build­ing in Lon­don in 1685. It includ­ed what would be the high­est dome ever built, at 365 feet off the ground. “For a tra­di­tion­al dome design to reach this height, it would have to span an open­ing that’s 160 feet or 49 meters wide, but this made it much too heavy for the walls below,” says Hicks. “Exist­ing tech­niques for build­ing this just could­n’t work.” Enter sci­en­tist-engi­neer Robert Hooke, who’d already been fig­ur­ing out ways to mod­el forces like this by hang­ing chains from the ceil­ing.

“Hooke’s genius was that he real­ized that the chain in his exper­i­ments was cal­cu­lat­ing the per­fect shape for it to remain in ten­sion, since that’s all it can do.” He explained domes as, phys­i­cal­ly, “the exact oppo­site of the chains. His famous line was, ‘As hangs the flex­ile line, so but invert­ed will stand the rigid arch.’ ” In oth­er words, “if you flip the shape of Hooke’s chain exper­i­ments upside down, the forces flip, and this shape is the per­fect com­pres­sion sys­tem.” Hence the dis­tinc­tive­ly elon­gat­ed-look­ing shape of the dome on the com­plet­ed St. Paul’s Cathe­dral, a depar­ture from all archi­tec­tur­al prece­dent.

The shape upon which Wren and Hooke set­tled turned out to be very sim­i­lar to what archi­tec­ture now knows as a cate­nary curve, a con­cept impor­tant indeed to Gaudí, who was “famous­ly enam­ored with what some call organ­ic forms.” He made detailed mod­els to guide the con­struc­tion of his projects, but after those he’d left behind for Sagra­da Família were destroyed by anar­chists in 1936, the builders had noth­ing to go on. Only in 1979 did the young archi­tect Mark Bur­ry “imag­ine the mod­els upside-down,” which brought about a new under­stand­ing of the build­ing’s com­plex, land­scape-like forms. It was a sim­i­lar phys­i­cal insight that made pos­si­ble such dra­mat­ic mid-cen­tu­ry build­ings as Anni­bale Vitel­lozzi and Pier Nervi’s Palazzet­to del­lo Sport and Eero Saari­nen’s TWA Flight Cen­ter: pure Space Age, but root­ed in the Enlight­en­ment.

Relat­ed con­tent:

How the World’s Biggest Dome Was Built: The Sto­ry of Fil­ip­po Brunelleschi and the Duo­mo in Flo­rence

How This Chica­go Sky­scraper Bare­ly Touch­es the Ground

Why Hasn’t the Pantheon’s Dome Col­lapsed?: How the Romans Engi­neered the Dome to Last 19 Cen­turies and Count­ing

An Archi­tec­tur­al Tour of Sagra­da Família, Antoni Gaudí’s Auda­cious Church That’s Been Under Con­struc­tion for 142 Years

A Guid­ed Tour of the Largest Hand­made Mod­el of Impe­r­i­al Rome: Dis­cov­er the 20x20 Meter Mod­el Cre­at­ed Dur­ing the 1930s

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities and the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

 

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Michio Kaku Demystifies the God Equation: The Key to Understanding Everything

in Physics | September 10th, 2024

It speaks to the impor­tance of dis­cov­er­ies in physics over the past few gen­er­a­tions that even the dis­in­ter­est­ed lay­man has heard of the field­’s cen­tral chal­lenge. In brief, there exist two sep­a­rate sys­tems: gen­er­al rel­a­tiv­i­ty, which describes the physics of space, time, and grav­i­ty, and quan­tum mechan­ics which describes the physics of fun­da­men­tal par­ti­cles like elec­trons and pho­tons. Each being applic­a­ble only at its own scale, one would seem to be incom­pat­i­ble with the oth­er. What the field needs to bring them togeth­er is kind of a “grand uni­fied the­o­ry,” a con­cept that has long since worked its way into pop­u­lar cul­ture.

In the Big Think video above, physi­cist Michio Kaku explains this sci­en­tif­ic quest for what he calls “the God equa­tion” in about five min­utes. Such an equa­tion “should uni­fy the basic con­cepts of physics.” But gen­er­al rel­a­tiv­i­ty as con­ceived by Albert Ein­stein is “based on smooth sur­faces,” while quan­tum mechan­ics is “based on chop­ping things up into par­ti­cles.”

The chal­lenge of bring­ing the two into con­cert has attract­ed “the great­est minds of the entire human race,” but to no defin­i­tive avail. At this point, Kaku says, only one con­cep­tion “has sur­vived every chal­lenge: string the­o­ry, which is what I do for a liv­ing” — and which has attained a rather high lev­el of pub­lic aware­ness, if not nec­es­sar­i­ly pub­lic under­stand­ing.

Kaku breaks it down as fol­lows: “If you can peer into the heart of an elec­tron, you would see that it’s a rub­ber band: a tiny, tiny vibrat­ing string, very sim­i­lar to a gui­tar string. There’s an infi­nite num­ber of vibra­tions, and that is why we have sub­atom­ic par­ti­cles,” each vari­ety of which cor­re­sponds to a dif­fer­ent vibra­tion. “A sim­ple idea that encap­su­lates the entire uni­verse” — and, cru­cial­ly, a math­e­mat­i­cal­ly con­sis­tent one — string the­o­ry has attract­ed astute pro­po­nents and detrac­tors alike, the lat­ter object­ing to its untesta­bil­li­ty. But one day, tech­nol­o­gy may well advance suf­fi­cient­ly to fal­si­fy it or not, and if not, the door opens to the pos­si­bil­i­ty of time machines, worm­holes, par­al­lel uni­vers­es, “things out of The Twi­light Zone.” A physi­cist can dream, can’t he?

For more on this sub­ject read Michio Kaku’s book The God Equa­tion: The Quest for the The­o­ry of Every­thing.

Relat­ed con­tent:

Michio Kaku Explains the Physics Behind Absolute­ly Every­thing

What Is Déjà Vu? Michio Kaku Won­ders If It’s Trig­gered by Par­al­lel Uni­vers­es

Michio Kaku & Bri­an Green Explain String The­o­ry in a Nut­shell: Ele­gant Expla­na­tions of an Ele­gant The­o­ry

Beau­ti­ful Equa­tions: Doc­u­men­tary Explores the Beau­ty of Ein­stein & Newton’s Great Equa­tions

Is There Life After Death?: Michio Kaku, Bill Nye, Sam Har­ris & More Explore One of Life’s Biggest Ques­tions

Bohemi­an Grav­i­ty: String The­o­ry Explored With an A Cap­pel­la Ver­sion of Bohemi­an Rhap­sody

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities and the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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How an Ancient Roman Shipwreck Could Explain the Universe

in History, Physics | August 21st, 2024

In a 1956 New States­man piece, the British sci­en­tist-nov­el­ist C. P. Snow first sound­ed the alarm about the increas­ing­ly chasm-like divide between what he called the “sci­en­tif­ic” and “tra­di­tion­al” cul­tures. We would today refer to them as the sci­ences and the human­i­ties, while still wring­ing our hands over the inabil­i­ty of each side to learn from (or even coher­ent­ly com­mu­ni­cate with) the oth­er. Nev­er­the­less, recent his­to­ry pro­vides the occa­sion­al heart­en­ing exam­ple of sci­ences-human­i­ties col­lab­o­ra­tion, few of them as dra­mat­ic as the sto­ry told in the SciShow video above, “An Ancient Roman Ship­wreck May Explain the Uni­verse.”

The ship­wreck in ques­tion occurred two mil­len­nia ago, off the west­ern coast of Sar­dinia. Hav­ing set sail from the min­ing cen­ter of Carte­ge­na, Spain, it was car­ry­ing more than 30 met­ric tons of lead, processed into a thou­sand ingots. An impor­tant met­al in the ancient Roman Empire, lead was used to make pipes (like the ones installed in aque­ducts), water tanks, roofs, and weapons of war. While our civ­i­liza­tion has grown jus­ti­fi­ably wary of putting water through lead pipes (and has at its com­mand much stronger met­als in any case), it still has plen­ty of use for the stuff, espe­cial­ly in shields against X‑rays and oth­er forms of activ­i­ty.

No mat­ter how lit­tle con­tact you have with the sci­en­tif­ic cul­ture, you can sure­ly appre­ci­ate how researchers in need of radioac­tiv­i­ty shields must have felt when this lead ingot-filled ship­wreck was dis­cov­ered in 1988. Hav­ing spent a cou­ple thou­sand years at the bot­tom of the ocean, the Roman lead aboard had lost most of its radioac­tiv­i­ty, mak­ing it ide­al for use in the shield of the Cryo­genic Under­ground Obser­va­to­ry for Rare Events (CUORE) at the Gran Sas­so Nation­al Lab­o­ra­to­ry in Italy. Engi­neered for research into the mass of neu­tri­nos, sub­atom­ic par­ti­cles long thought to have no mass at all, CUORE held out the promise of data that could lead to insights into the ori­gin of the uni­verse.

Ulti­mate­ly, the physi­cists and archae­ol­o­gists struck a deal, allow­ing the for­mer to melt down the least-well pre­served ingots from the ship­wreck (after first remov­ing the his­tor­i­cal­ly valu­able inscrip­tions from its man­u­fac­tur­er) and use it to shield the high­ly sen­si­tive CUORE from out­side radi­a­tion. The design worked, but as of last year, none of the exper­i­ments have pro­duced con­clu­sive results about the role of neu­tri­nos in the emer­gence of life, the uni­verse, and every­thing. Prob­ing that ques­tion fur­ther will be a job for CUORE’s suc­ces­sor CUPID (CUORE Upgrade with Par­ti­cle Iden­ti­fi­ca­tion), sched­uled to come online lat­er this year. Though C. P. Snow nev­er lived to see these projects, he sure­ly would­n’t be sur­prised that, to find con­ver­gence between the sci­ences and the human­i­ties, you’ve got to dive deep.

Relat­ed con­tent:

New­ly Dis­cov­ered Ship­wreck Proves Herodotus, the “Father of His­to­ry,” Cor­rect 2500 Years Lat­er

How the Ancient Greeks Invent­ed the First Com­put­er: An Intro­duc­tion to the Antikythera Mech­a­nism (Cir­ca 87 BC)

See the Well-Pre­served Wreck­age of Ernest Shackleton’s Ship Endurance Found in Antarc­ti­ca

The First Full 3D Scan of the Titan­ic, Made of More Than 700,000 Images Cap­tur­ing the Wreck’s Every Detail

“The Val­ue of Cul­ture” Revealed in a New BBC Radio Series by Melvyn Bragg

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities and the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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The Life & Work of Richard Feynman Explored in a Three-Part Freakonomics Radio Miniseries

in Physics, Science | February 27th, 2024

Here at Open Cul­ture, Richard Feyn­man is nev­er far from our minds. Though he dis­tin­guished him­self with his work on the devel­op­ment of the atom­ic bomb and his Nobel Prize-win­ning research on quan­tum elec­tro­dy­nam­ics, you need no spe­cial inter­est in either World War II or the­o­ret­i­cal physics to look to him as an intel­lec­tu­al mod­el. In the years after his death in 1988, his leg­end grew as not just a sci­en­tif­ic mind but even more so as a ver­i­ta­ble per­son­i­fi­ca­tion of curios­i­ty, sur­round­ed by sto­ries (delib­er­ate­ly cul­ti­vat­ed by him in his life­time) of safe-crack­ing, bon­go-play­ing, and nude mod­el-draw­ing, to the point that Feyn­man the man became some­what hard to dis­cern.

In the view of Freako­nom­ics Radio host Stephen Dub­n­er, Feyn­man’s pub­lic pro­file has late­ly fall­en into an unfor­tu­nate desue­tude. It seems that peo­ple just don’t talk about him the way they used to, hard though that is to imag­ine for any of us who grew up read­ing col­lec­tions of anec­dotes like Sure­ly You’re Jok­ing, Mr. Feyn­man!.

Oper­at­ing on the sup­po­si­tion that we could all use more Feyn­man in our lives, Freako­nom­ics Radio has, over the past month, put out a three-part series cov­er­ing his life and work, from his recruit­ment to the Man­hat­tan Project and lat­er pub­lic analy­sis of the Chal­lenger dis­as­ter to his years teach­ing at Cal­tech to his late-in-life exper­i­men­ta­tion with psy­che­del­ic sub­stances (fur­ther explored in a fourth, bonus episode).

“The Curi­ous, Bril­liant, Van­ish­ing Mr. Feyn­man” (also avail­able on Apple and Spo­ti­fy) includes a vari­ety of inter­views with its sub­jec­t’s friends, rel­a­tives, col­lab­o­ra­tors, and suc­ces­sors. All speak high­ly of him, though some com­pli­cate the leg­end by look­ing at the down­sides of his idio­syn­crat­ic atti­tudes toward both sci­ence and the social world: his insis­tence on under­stand­ing every­thing by fig­ur­ing it out him­self from scratch may have led to him mak­ing few­er dis­cov­er­ies than he would have, had he made more use of the research of oth­ers, and his enthu­si­asm for wom­ankind, shall we say, man­i­fest­ed in ways that would prob­a­bly gen­er­ate calls for “can­cel­la­tion” today. But just as Feyn­man eschewed the label of “genius,” he nev­er claimed to be a per­fect human being. And besides, it isn’t his social incli­na­tions or even his bon­go skills we should admire, but his ded­i­ca­tion to defeat­ing “lousy ideas” — which, as he no doubt expect­ed, have only pro­lif­er­at­ed since he left us.

Relat­ed con­tent:

What Made Richard Feyn­man One of the Most Admired Edu­ca­tors in the World

The Feyn­man Lec­tures on Physics, The Most Pop­u­lar Physics Book Ever Writ­ten, Is Now Com­plete­ly Online

How Richard Feynman’s Dia­grams Rev­o­lu­tion­ized Physics

Watch a New Ani­ma­tion of Richard Feynman’s Ode to the Won­der of Life, with Music by Yo-Yo Ma

The “Feyn­man Tech­nique” for Study­ing Effec­tive­ly: An Ani­mat­ed Primer

“The Char­ac­ter of Phys­i­cal Law”: Richard Feynman’s Leg­endary Course Pre­sent­ed at Cor­nell, 1964

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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Why Perpetual Motion Machines Never Work, Despite Centuries of Experiments

in History, Physics, Technology | January 16th, 2024

Accord­ing to the laws of physics — at least in sim­pli­fied form — an object in motion will stay in motion, at least if no oth­er forces act on it. That’s all well and good in the realm of the­o­ry, but here in the com­plex real­i­ty of Earth, there always seems to be one force or anoth­er get­ting in the way. Not that this has ever com­plete­ly shut down mankind’s desire to build a per­pet­u­al-motion machine. Accord­ing to Google Arts & Cul­ture, that quest dates at least as far back as sev­enth-cen­tu­ry India, where “the math­e­mati­cian Brah­magup­ta, who want­ed to rep­re­sent the cycli­cal and eter­nal motion of the heav­ens, designed an over­bal­anced wheel whose rota­tion was pow­ered by the flow of mer­cury inside its hol­low spokes.”

More wide­ly known is the suc­ces­sor design by Brah­magup­ta’s twelfth-cen­tu­ry coun­try­man and col­league Bhāskara, who “altered the wheel design by giv­ing the hol­low spokes a curved shape, pro­duc­ing an asym­met­ri­cal course in con­stant imbal­ance.” Despite this ren­di­tion’s mem­o­rable ele­gance, it does not, like the ear­li­er over­bal­anced wheel, actu­al­ly keep on turn­ing for­ev­er. To blame are the very same laws of physics that have dogged the sub­se­quent 900 or so years of attempts to build per­pet­u­al-motion machines, which you can see briefly explained in the TED-Ed video above.

“Ideas for per­pet­u­al-motion machines all vio­late one or more fun­da­men­tal laws of ther­mo­dy­nam­ics, the branch of physics that describes the rela­tion­ship between dif­fer­ent forms of ener­gy,” says the nar­ra­tor. The first law holds that “ener­gy can’t be cre­at­ed or destroyed; you can’t get out more ener­gy than you put in.” That alone would put an end to hopes for a “free” ener­gy source of this kind. But even machines that just keep mov­ing by them­selves — much less use­ful, of course, but still sci­en­tif­i­cal­ly earth-shat­ter­ing — would even­tu­al­ly “have to cre­ate some extra ener­gy to nudge the sys­tem past its stop­ping point, break­ing the first law of ther­mo­dy­nam­ics.”

When­ev­er machines seem to over­come this prob­lem, “in real­i­ty, they invari­ably turn out to be draw­ing ener­gy from some exter­nal source.” (Nine­teenth-cen­tu­ry Amer­i­ca seems to have offered end­less oppor­tu­ni­ties for engi­neer­ing char­la­tanism of this kind, whose per­pe­tra­tors made a habit of skip­ping town when­ev­er their trick­ery was revealed, some obtain­ing patents and prof­its all the while). But even if the first law of ther­mo­dy­nam­ics did­n’t apply, there would remain the mat­ter of the sec­ond, which dic­tates that “ener­gy tends to spread out through process­es like fric­tion,” thus “reduc­ing the ener­gy avail­able to move the sys­tem itself, until the machine inevitably stopped.” Hence the aban­don­ment of inter­est in per­pet­u­al motion by such sci­en­tif­ic minds as Galileo and Leonar­do — who must also have under­stood that mankind would nev­er ful­ly relin­quish the dream.

Relat­ed con­tent:

Leonar­do da Vinci’s Ele­gant Design for a Per­pet­u­al Motion Machine

M. C. Escher’s Per­pet­u­al Motion Water­fall Brought to Life: Real or Sleight of Hand?

Leonar­do da Vinci’s Inven­tions Come to Life as Muse­um-Qual­i­ty, Work­able Mod­els: A Swing Bridge, Scythed Char­i­ot, Per­pet­u­al Motion Machine & More

How the Bril­liant Col­ors of Medieval Illu­mi­nat­ed Man­u­scripts Were Made with Alche­my

A Com­plete Dig­i­ti­za­tion of Leonar­do Da Vinci’s Codex Atlanti­cus, the Largest Exist­ing Col­lec­tion of His Draw­ings & Writ­ings

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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The Physics of Playing a Guitar Visualized: Metallica’s “Nothing Else Matters” Seen from the Inside of a Guitar

in Music, Physics | October 6th, 2023

Give it a chance, you won’t be dis­ap­point­ed. While the first 30 sec­onds of the video above may resem­ble an ama­teur iPhone prank, it soon becomes some­thing unex­pect­ed­ly enchanting—a visu­al­iza­tion of the physics of music in real-time. The Youtu­ber places his phone inside an acoustic gui­tar, then plays Metallica’s “Noth­ing Else Mat­ters” against a back­drop of clouds and blue sky. Due to what Twist­ed Sifter iden­ti­fies as the phone camera’s rolling shut­ter effect, the actu­al waves of the vibrat­ing gui­tar strings are as clear­ly vis­i­ble as if they were on an oscil­lo­scope.

The com­par­i­son is an apt one, since we might use exact­ly such a device to mea­sure and visu­al­ize the acoustic prop­er­ties of stringed instru­ments. “A gui­tar string”—writes physi­cist and musi­cian Sam Hokin in his short explanation—is a com­mon exam­ple of a string fixed at both ends which is elas­tic and can vibrate.

The vibra­tions of such a string are called stand­ing waves, and they sat­is­fy the rela­tion­ship between wave­length and fre­quen­cy that comes from the def­i­n­i­tion of waves.”

Those with a physics back­ground might appre­ci­ate The Physics Class­room’s tech­ni­cal descrip­tion of gui­tar string vibra­tion, with sev­er­al tech­ni­cal dia­grams. For oth­ers, the video above by Youtube physics teacher Doc Shus­ter may be a bet­ter for­mat. Shus­ter explains such enti­ties as nodes and antin­odes (you’ll have to tell me if you get any of his jokes). And at about 2:25, he digress­es from his mus­ings on these phe­nom­e­na to talk about gui­tar strings specif­i­cal­ly, which “make one note for a giv­en tight­ness of the string, a giv­en weight of the string, and a giv­en length of the string.”

This is, of course, why chang­ing the length of the string by press­ing down on it changes the note the string pro­duces, and it applies to all stringed instru­ments and the piano. Oth­er fac­tors, says Shus­ter, like the body of the gui­tar, use of pick­ups, etc., have a much small­er effect on the fre­quen­cy of a gui­tar string than tight­ness, weight, and length. We see how the com­plex­i­ty of dif­fer­ent stand­ing wave forms relates to har­mon­ics (or over­tones). And when we return to the Metal­li­ca video at the top, we’ll have a bet­ter under­stand­ing of how the strings vibrate dif­fer­ent­ly as they pro­duce dif­fer­ent fre­quen­cies at dif­fer­ent har­mon­ics.

Shuster’s video quick­ly laps­es into cal­cu­lus, and you may or may not be lost by his expla­na­tions. The Physics Class­room has some excel­lent, free tuto­ri­als on var­i­ous types of waves, pitch fre­quen­cy, vibra­tion, and res­o­nance. Per­haps all we need to keep in mind to under­stand the very basics of the sci­ence is this, from their intro­duc­tion: “As a gui­tar string vibrates, it sets sur­round­ing air mol­e­cules into vibra­tional motion. The fre­quen­cy at which these air mol­e­cules vibrate is equal to the fre­quen­cy of vibra­tion of the gui­tar string.” The action of the string pro­duces an equal and oppo­site reac­tion in the air, which then cre­ates “a pres­sure wave which trav­els out­ward from its source.” The pres­sure waves strike our eardrums, our brains inter­pret sound, and there you have it.

If you would like to sign up for Open Culture’s free email newslet­ter, please find it here. Or fol­low our posts on Threads, Face­book, BlueSky or Mastodon.

If you would like to sup­port the mis­sion of Open Cul­ture, con­sid­er mak­ing a dona­tion to our site. It’s hard to rely 100% on ads, and your con­tri­bu­tions will help us con­tin­ue pro­vid­ing the best free cul­tur­al and edu­ca­tion­al mate­ri­als to learn­ers every­where. You can con­tribute through Pay­Pal, Patre­on, and Ven­mo (@openculture). Thanks!

Note: An ear­li­er ver­sion of this post appeared on our site in 2015.

Relat­ed Con­tent:

Metal­li­ca Plays Antarc­ti­ca, Set­ting a World Record as the First Band to Play All 7 Con­ti­nents: Watch the Full Con­cert Online

Jazz Drum­mer Lar­nell Lewis Hears Metallica’s “Enter Sand­man” for the Very First Time, Then Plays It Near-Per­fect­ly

Watch Metal­li­ca Play “Enter Sand­man” Before a Crowd of 1.6 Mil­lion in Moscow, Dur­ing the Final Days of the Sovi­et Union (1991)

Free Online Physics Cours­es

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

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Oppenheimer’s Secret City: The Story Behind the Stealthy Creation of Los Alamos, New Mexico

in History, Physics | July 27th, 2023

We think of the atom­ic bomb as a destroy­er of cities, name­ly Hiroshi­ma and Nagasa­ki. But its devel­op­ment also pro­duced a city: Los Alam­os, New Mex­i­co, an offi­cial­ly non-exis­tent com­mu­ni­ty in which the nec­es­sary research could be con­duct­ed in secret. More recent­ly, it became a major shoot­ing loca­tion for Oppen­heimer, Christo­pher Nolan’s new movie about the tit­u­lar the­o­ret­i­cal physi­cist remem­bered as the father (or one of the fathers) of the atom­ic bomb based on his work as the direc­tor of the Los Alam­os Lab­o­ra­to­ry. You can learn more about that lab­o­ra­to­ry, and the town of 6,000 con­struct­ed to sup­port it, in the new Vox video above.

Los Alam­os was nec­es­sary to the Man­hat­tan Project, as the R&D of the world’s first nuclear weapon was code-named, but it was­n’t suf­fi­cient: oth­er secret sites involved includ­ed “a nuclear reac­tor under a Uni­ver­si­ty of Chica­go foot­ball field”; “the Alaba­ma Ordi­nance Works, for pro­duc­ing heavy water”; “a large plant for the enrich­ment of ura­ni­um and pro­duc­tion of some plu­to­ni­um” in Oak Ridge, Ten­nessee”; and the Han­ford Engi­neer Works in Wash­ing­ton State, which pro­duced even more plu­to­ni­um.

But the bomb itself was cre­at­ed in Los Alam­os, into whose iso­la­tion Oppen­heimer recruit­ed the likes of Enri­co Fer­mi, Edward Teller, Richard Feyn­man, and oth­er pow­er­ful sci­en­tif­ic minds — who brought their wives and chil­dren along.

As a 1944 Med­ical Corp memo warned, the “intel­lec­tu­als” at Los Alam­os would “seek more med­ical care than the aver­age per­son”; at the same time, one-fifth of the mar­ried women there were preg­nant, so up went mater­ni­ty wards as well. The pop­u­la­tion of Los Alam­os grew so rapid­ly that “hut­ments were a com­mon form of accom­mo­da­tion,” though “apart­ment build­ings were also avail­able.” The hous­ing sat along­side “facil­i­ties for graphite fab­ri­ca­tion, and the cyclotron and Van de Graaff machines.” Less than 250 miles south lay what, in the sum­mer of 1945, would become the site of the Trin­i­ty test. It was there, gaz­ing upon the explo­sion of the unprece­dent­ed nuclear weapon whose devel­op­ment he’d over­seen, that Oppen­heimer saw not mere­ly a destroy­er of cities, but a destroy­er of worlds.

Relat­ed con­tent:

Oppen­heimer: The Man Behind the Bomb

Watch Chill­ing Footage of the Hiroshi­ma & Nagasa­ki Bomb­ings in Restored Col­or

J. Robert Oppen­heimer Explains How, Upon Wit­ness­ing the First Nuclear Explo­sion, He Recit­ed a Line from the Bha­gavad Gita: “Now I Am Become Death, the Destroy­er of Worlds”

See Every Nuclear Explo­sion in His­to­ry: 2153 Blasts from 1945–2015

Learn How Richard Feyn­man Cracked the Safes with Atom­ic Secrets at Los Alam­os

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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Does Einstein’s Theory of Special Relativity Suggest That There Is an Afterlife?: A Theoretical Physicist Explains

in Physics | July 20th, 2023

“Let’s talk about the physics of dead grand­moth­ers.” Thus does the­o­ret­i­cal physi­cist Sabine Hossen­felder start off the Big Think video above, which soon gets into Ein­stein’s the­o­ry of spe­cial rel­a­tiv­i­ty. The ques­tion of how Hossen­felder man­ages to con­nect the for­mer to the lat­ter should raise in any­one curios­i­ty enough to give these ten min­utes a watch, but she also address­es a cer­tain com­mon cat­e­go­ry of mis­con­cep­tion. It all began, she says, when a young man posed to her the fol­low­ing ques­tion: “A shaman told me that my grand­moth­er is still alive because of quan­tum mechan­ics. Is this right?”

Upon reflec­tion, Hossen­felder arrived at the con­clu­sion that “it’s not entire­ly wrong.” For decades now, “quan­tum mechan­ics” has been hauled out over and over again to pro­vide vague sup­port to a range of beliefs all along the spec­trum of plau­si­bil­i­ty. But in the dead-grand­moth­er case, at least, it’s not the applic­a­ble area of physics. “It’s actu­al­ly got some­thing to do with Ein­stein’s the­o­ry of spe­cial rel­a­tiv­i­ty,” she says. With that par­tic­u­lar achieve­ment, Ein­stein changed the way we think about space and time, prov­ing that “every­thing that you expe­ri­ence, every­thing that you see, you see as it was a tiny, lit­tle amount of time in the past. So how do you know that any­thing exists right now?”

In Ein­stein’s descrip­tion of phys­i­cal real­i­ty, “there is no unam­bigu­ous notion to define what hap­pens now; it depends on the observ­er.” And “if you fol­low this log­ic to its con­clu­sion, then the out­come is that every moment could be now for some­one. And that includes all moments in your past, and it also includes all moments in your future.” Ein­stein posits space and time as not two sep­a­rate con­cepts, but aspects of a sin­gle enti­ty called space­time, in which “the present moment has no fun­da­men­tal sig­nif­i­cance”; in the result­ing “block uni­verse,” past, present, and future coex­ist simul­ta­ne­ous­ly, and no infor­ma­tion is ever destroyed, just con­tin­u­al­ly rearranged.

“So if some­one you knew dies, then, of course, we all know that you can no longer com­mu­ni­cate with this per­son. That’s because the infor­ma­tion that made up their per­son­al­i­ty dis­pers­es into very sub­tle cor­re­la­tions in the remains of their body, which become entan­gled with all the par­ti­cles around them, and slow­ly, slow­ly, they spread into radi­a­tion that dis­pers­es through­out the solar sys­tem, and even­tu­al­ly, through­out the entire uni­verse.” But one day could bring “some cos­mic con­scious­ness­es which will also be spread out, and this infor­ma­tion will be acces­si­ble again” — in about a bil­lion years, any­way, which will at least give grand­ma’s reassem­bled intel­li­gence plen­ty to catch up on.

Relat­ed con­tent:

Is There Life After Death?: Michio Kaku, Bill Nye, Sam Har­ris & More Explore One of Life’s Biggest Ques­tions

Elie Wiesel (RIP) Talks About What Hap­pens When We Die

Is There an After­life? Christo­pher Hitchens Spec­u­lates in an Ani­mat­ed Video

Einstein’s The­o­ry of Rel­a­tiv­i­ty Explained in One of the Ear­li­est Sci­ence Films Ever Made (1923)

Is There Life After Death?: John Cleese and a Pan­el of Sci­en­tists Dis­cuss That Eter­nal Ques­tion

Albert Ein­stein On God: “Noth­ing More Than the Expres­sion and Prod­uct of Human Weak­ness”

Based in Seoul, Col­in Marshall writes and broad­casts on cities, lan­guage, and cul­ture. His projects include the Sub­stack newslet­ter Books on Cities, the book The State­less City: a Walk through 21st-Cen­tu­ry Los Ange­les and the video series The City in Cin­e­ma. Fol­low him on Twit­ter at @colinmarshall or on Face­book.

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