{"product_id":"schwingers-α-2π-plate-055-physics-poster","title":"Schwinger's α\/2π – Plate 055 Physics Poster","description":"\u003cp\u003ePlate 55 speaks for itself: \u003cem\u003e“Small extra spin.”\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eDirac's theory gives the electron g = 2. Quantum electrodynamics adds a small correction; Schwinger's first-order term is α\/2π.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ea = (g − 2)\/2 ≈ α\/2π\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003ea: anomalous magnetic moment, dimensionless\u003c\/li\u003e\n\u003cli\u003eg: g-factor, dimensionless\u003c\/li\u003e\n\u003cli\u003eα: fine-structure constant ≈ 1\/137.036, dimensionless\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eDirac g = 2; measured: slightly more. Schwinger 1948: a = α\/2π ≈ 0.0011614.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e α\/2π is the leading term; the measured a_e = 0.00115965218… agrees once higher-order QED terms are included.\u003c\/p\u003e\u003ch3\u003eSources\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eJ. Schwinger, Phys. Rev. 73, 416 (1948).\u003c\/li\u003e\n\u003cli\u003eX. Fan et al., Phys. Rev. Lett. 130, 071801 (2023).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOn the poster\u003c\/h3\u003e\u003cp\u003ePlate 055, “Schwinger's α\/2π”: the pixel-art plate with its slogan “Small extra spin.”, the key equation and the facts panel shown above. Pixelated Physics. Physics. Personified.\u003c\/p\u003e","brand":"Printify","offers":[{"title":"9'' x 12\" (Vertical) \/ Matte","offer_id":50962507726951,"sku":"92241412525896142765","price":19.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Fine Art","offer_id":50962507759719,"sku":"63518425060646649234","price":29.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Semi Glossy","offer_id":50962507792487,"sku":"21600108749273696203","price":19.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Fine Art","offer_id":50962507825255,"sku":"11951162748753356879","price":44.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Semi Glossy","offer_id":50962507858023,"sku":"13119446597991360847","price":29.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Matte","offer_id":50962507890791,"sku":"25206226362616299227","price":29.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Matte","offer_id":50962507923559,"sku":"18682361815486996095","price":69.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Fine Art","offer_id":50962507956327,"sku":"24720926234327618122","price":119.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Semi Glossy","offer_id":50962507989095,"sku":"19574519662427778629","price":69.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/17096781165678940246_2048.jpg?v=1793634841","url":"https:\/\/pixelatedphysics.com\/sv\/products\/schwingers-%ce%b1-2%cf%80-plate-055-physics-poster","provider":"Pixelated Physics","version":"1.0","type":"link"}