CINXE.COM

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="390"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "pubs.aip.org",cType: 'managed',cRay: '92da0963e8807e8d',cH: 'aL1crJ68NnUJFmzmJU7gM3k14v40P8f7Vacoo3_zh0k-1744202046-1.2.1.1-mgaTycPBTr2AANsjBCSKSDoT3FftzYZMjA2.E2mX0SHB0gPDgQuBxaT8OBFkB4dS',cUPMDTk: "\/physicstoday\/article\/68\/11\/30\/414987\/Arch-and-scaffold-How-Einstein-found-his-field?__cf_chl_tk=AgEFV6dxlmYNjdR01Ug59J.oIIuMKhlHBYg11VyCPPw-1744202046-1.0.1.1-TVYYvKs8Vi7vclnXk0yOiMEfaxPWeH0mF6c6B1FDZMc",cFPWv: 'g',cITimeS: '1744202046',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "unsupported_browser_beacon",fa: "\/physicstoday\/article\/68\/11\/30\/414987\/Arch-and-scaffold-How-Einstein-found-his-field?__cf_chl_f_tk=AgEFV6dxlmYNjdR01Ug59J.oIIuMKhlHBYg11VyCPPw-1744202046-1.0.1.1-TVYYvKs8Vi7vclnXk0yOiMEfaxPWeH0mF6c6B1FDZMc",md: "sY8Dwf0XBwfwTt8tMZV1WKq0vi3iwqSpoKK2urWwnP8-1744202046-1.2.1.1-xKSkmPh.L7w0MuZd6G50Hb.aX2vxcukmRm0cOHoex5tQE7QAjGPdojW_Hn3T1oiY8E4vHKZ3Y8uDLMKUE1nByd6IX1o50VYlQ_LVCo5Mk0764.7U_Zy3X8Yq9OwkoGzkGSq6M3D3hMoJgA4qm64NP_UCESN01aIt5I5xxKkxLXgXAuVVwNvXf2x9PtGFrH.eILsRGklU0A41Grh_NPZp6IqVeyca8i9ToME0SX6hv7oqiGveK48OsOjobpqjtKhmQXes2dpdyYnssgfa6SBJyUdgE18Lsfq2MErYmrF0M1DgQLvF348Mrlf9g5RJ8Fq9qWuV0MmnifIYi2N5LDazpL24EzKMS21Tm7X6qaIQpMHj9ExxAJziMGT5s.bBHa0VbPDlCXXnmC.rMMp6aDizGAz3uTe8xU5c2mL0m7RVkyJ.UB9TXfnN2II4O1VK1DcENxIYDyrreFyuurCpr8kABMVwCLWTZ72wPhXXy1womWPh4F1X7i2vGYY0m2b9Rbz1XBM93xHMqlS6IpHTCzk41C0l.zv3wYF9CmEygHYviTJUii.fjp39yT0dRpRN7VWtZTKxswBICeltVI6ufLrnyhqXV0p4dTvpnIunm0EF6WvQCODL8EnMau3BAxB9Ag1FiD.cMvyB0omZ2qxQsiy79feCInyCjpbBUCDhClpYpGq.b8j.DnbMe29Vl1D0_QG42bmb4Zz71XNJAj9X.KYOceL16ktazYoY5NW7qtIdeXDmnN667q68H4Q8TjGS_UZ8JpFhc9mOONwg3TwFq7A7AD07YS124TZHlUIGKMFmFCDAQT3lPeNt6qU5.T2W_IyVR8sOKDX0fZcLdYP.1LCQCAg_uNaKhtcDv4MLtDAXsXQNCboiNKzYPO5TYDA0U0ky2x.NRqyLp6YYf.hjHGeAnaSd0NgnehA5sH_yjnTBhjaBZn1QB2bNA0ial_M4LeuLkyj6S4F5fdcNG2vrZaz22LFom66Kuzueh6LsolxEQS0n.Z8cSI6UrHhut89I_62ZNTB5RiG40L8NKW0GeLL_nPWidA.OhJvnToahHb8Z9n7Q2IBWWC4TcVdfGnF5Lpv5e3rh1OkFWLjL9u4e6XE.LK1gvyuPwsXT3Nsvk7L9LnsJKsQ.KR.r_VrKkzX7BVGO4QPARKMd27LI2QXpD2gSuxpT_5BBEHGlZOVp01bo8sNA2YRVD8n4GwSvnpxN6UepErMwppK1DM3C5Hpr5Ar9dBGTys0w7NjFalamdqFaG7O2iffXFmr_8zjZRAARdLiP.y1O.J6M88wGeqXQpK4I0IzoD2.Yi2lE4NSdsLpHsS.cV_lcLyRClDN.abo07FL8YbmuUtjoEnOwubWIMGVsQ_aE8FPDYnRRSQsQ1ukFphfpo_O3WKQUuHXIeWgAeiBusddbhTN6WiefItA4NO4HG7_boPOwJ2.i4HdGokbFD4Q",mdrd: "C.1n5OrDiT0ROYYZ20I2LvSIqAVlRIKgUVtrR8vu8KM-1744202046-1.2.1.1-6NZPRvOTbu3uS6khfdrS3QSREYKh7c7iHme5NNbyspQuZxXwC5s9Bf2b1dap4brRJOWhqWZIVrhmc0vhLQh9btEuad4Iir3usYVZaX.VIh.k6_eT6s8eD5qrO6LvmAiiCncUuhWYfrqT1OcKXiLTfsxa8vn86lNWaAFctyLTV9_ncIsegFptQ7BrbyATyHWZA6.z4jWP2eFELYeU5KoDfQ60Vr_RNFpUeeteEmNV5X996w2H_3Fck3TBVRcimNDP96ZfPi6pcqwefv28dK2dTTbiSJvoMmGq_fy7yO4peX9pplmTVJl0ozY044bWFw8WRcS4P_kKdcoOOxc7m5ss2z0._9xPiL1HPAjzsAiLDOESD5wNrS_hokL3NVME7uvTkEfdj1fJhYbjomyjM9rokvXwiIbm7JDyA1bfPaxPjBfnbh6NDKShmluMpL9RkfkFUJrWAxQLldBX2ATppUiQoAoghhAD2UtlY3o5swI3IamF.Bh5SLxDmQAKbYl_7lxJaBtxrItLhi3KgAS1aHUEPS8gO2a1CJvg00fkVcfLNnYrjF1cl4y4KAPnEtYK6tRl4W_RnaAWXappVorhxgGm6a8Dvf4LEqANhm3Pkp5mmV._M2mBrFAStiLZ07U2abaRortb6750kenTgKW4LFYdePu4EgrCd2iiCqepL2QeMaub4qBoLrmtlObcy_BxSGNb0h0eXPgHgDZjI39LTWvsaJJK6_85CuD6iGI6Dk6XnxOF8fAHCbqc9pDXHEAPWGMEdAdoqRI0RKVqBUnqQeqmUxi291hhEItgje1Wp9QW7i5HcDAbHZUl8i_C82OZqXJfSQYMsayJyhXSnNaUaAMFBPipJch1H33Ch7X7TakwtsDEY8653V0mGUhxHbmlflp8sopFa8Sz580O9j_VrZTY1rHGFJyi.k5kng5glVOey3cqeIpDpKB33IMrc6LCbPw9jRcdTQZyVFWxFKxb_VDIij66yHwMzQOxoxT1AD7EH2pb4SJEMcDq0P_K27U44uwo_mosOAY59DGtyo2jg_GbYEzQ6rQbd7AZkCUHJEmqGABYTiVVVs8DLNG1CdHItZ706KG1FUfOr74g1T0qtatiSwml47ByE9u0dxDy7BbOMAe5W2WLJjxvS0TfZwjxzkMTU3TZQdoHbEZ5qwevH0fZrfQcbEgWcdxBq3gPnoAGY.RsTc9NRzClntIngdDy7iM2Q7c6wr6mAM94ysKpz9d2NXHsm21C0CLb.8R6WzrY7_Fyy4lutVaLpqjV6tTL8CI_8V54skU3KPws2lF9Hw_T5OQzTflZahLjhC365MEMjcChSWysPXeayOFfoY.Yuxha.a0dsOTXw.tiyvznb0r5RCdU3XL_cyYvPtakl9hrhJ_PtyO1RSXVIOmQlEHHgleKLcI4yJWej1FXQhlA7e_bhm45XE7TIuj_IoeBCHDbAxdzgyGe1qN_5w0dMDgO5NCrpj0T4U12vnkdFUsRnqeEaIqG6Kb0lD._Vqbe6CBnBiOimHPzEZSbPVp8Rrrsg2LfOL6A6YvmiAU9c2sem80cfbH1SJ4bwDgye.bTyFQUummfmaRc8.AYdvvcCi0SD.n1jjei5IgXz08Jub29t4VIDbu4ioJlTC9B4AHFAhqFD.cpDu0TFDoHtYlWKiQDOeI71L8H24VG8TD0n_i1SECPGxEUL74uwI3BiMrr4It_NECxJCYaRakopMvmnzkJvftjGmEtAhi954q62Bdc9teCezgi2kCPAqn7hdAbtDN9aXooezzg1JvREAYfzELi7hroWQ9H3L2RIRcwgins8LQ7Asj2nb8AU9wMzp6Q6wlBUjQvWxQsgh4FbR6.DBIWdEKyvYemWG_YHi4s4AX66SSsrDN_3FRqsqvpZ480LLSzChCLWazWSxhZZso_veOhiPr1.dBDCqguoExk562nYywUIiCxReHRf2CfLhJ1cGOBBQZDr1yOe9X9HOxmZl9v_j9rwnugKOSeEnfGVGSeWw_V.dcw_YeJ_gHeSdYYW9w216j4F0c5Ho9.joAgaA4aCJzQ"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=92da0963e8807e8d';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/physicstoday\/article\/68\/11\/30\/414987\/Arch-and-scaffold-How-Einstein-found-his-field?__cf_chl_rt_tk=AgEFV6dxlmYNjdR01Ug59J.oIIuMKhlHBYg11VyCPPw-1744202046-1.0.1.1-TVYYvKs8Vi7vclnXk0yOiMEfaxPWeH0mF6c6B1FDZMc" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>