{"product_id":"friedmanns-three-fates-plate-071-physics-poster","title":"Friedmann's Three Fates – Plate 071 Physics Poster","description":"\u003cp\u003ePlate 71 speaks for itself: \u003cem\u003e“One equation, three possible endings.”\u003c\/em\u003e\u003c\/p\u003e\u003ch3\u003eThe Physics\u003c\/h3\u003e\u003cp\u003eFriedmann's equation ties the expansion rate to density, curvature and the cosmological constant. Depending on their balance, a universe recollapses, expands forever, or accelerates.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eH² = 8πGρ\/3 − k c²\/a² + Λ c²\/3\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eH: Hubble parameter, s⁻¹\u003c\/li\u003e\n\u003cli\u003eG: gravitational constant, m³ kg⁻¹ s⁻²\u003c\/li\u003e\n\u003cli\u003eρ: density, kg m⁻³\u003c\/li\u003e\n\u003cli\u003ek: curvature constant, m⁻² (comoving)\u003c\/li\u003e\n\u003cli\u003ec: speed of light, m s⁻¹\u003c\/li\u003e\n\u003cli\u003ea: scale factor, dimensionless\u003c\/li\u003e\n\u003cli\u003eΛ: cosmological constant, m⁻²\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003ePlanck 2018: H₀ = 67.36 ± 0.54 km\/s\/Mpc. Friedmann, Z. Phys. 10, 377 (1922).\u003c\/p\u003e\u003cp\u003e\u003cem\u003eHonest caveat:\u003c\/em\u003e With Λ the 'three fates' are not tied to curvature alone; a closed universe with enough Λ can still expand forever.\u003c\/p\u003e\u003ch3\u003eSources\u003c\/h3\u003e\u003cul\u003e\n\u003cli\u003eA. Friedmann, Z. Phys. 10, 377 (1922).\u003c\/li\u003e\n\u003cli\u003ePlanck Collaboration, Astron. Astrophys. 641, A6 (2020).\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch3\u003eOn the poster\u003c\/h3\u003e\u003cp\u003ePlate 071, “Friedmann's Three Fates”: the pixel-art plate with its slogan “One equation, three possible endings.”, 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":50962643583079,"sku":"33788786273171128946","price":19.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Fine Art","offer_id":50962643615847,"sku":"10989931631385715746","price":29.99,"currency_code":"USD","in_stock":true},{"title":"9'' x 12\" (Vertical) \/ Semi Glossy","offer_id":50962643648615,"sku":"10197539229044949540","price":19.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Fine Art","offer_id":50962643681383,"sku":"16922435897878073223","price":44.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Semi Glossy","offer_id":50962643714151,"sku":"58716702200247329094","price":29.99,"currency_code":"USD","in_stock":true},{"title":"18″ x 24″ (Vertical) \/ Matte","offer_id":50962643746919,"sku":"74838229239769333355","price":29.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Matte","offer_id":50962643779687,"sku":"91215045837507917451","price":69.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Fine Art","offer_id":50962643812455,"sku":"29650103929580013524","price":119.99,"currency_code":"USD","in_stock":true},{"title":"36'' x 48\" (Vertical) \/ Semi Glossy","offer_id":50962643845223,"sku":"48966396878136077273","price":69.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0596\/8746\/9159\/files\/1356077152819376923_2048.jpg?v=1793635491","url":"https:\/\/pixelatedphysics.com\/pt\/products\/friedmanns-three-fates-plate-071-physics-poster","provider":"Pixelated Physics","version":"1.0","type":"link"}