{"id":24568,"date":"2011-12-12T11:25:52","date_gmt":"2011-12-12T10:25:52","guid":{"rendered":"http:\/\/www.astb.se\/cassiopeiabloggen\/?p=24568"},"modified":"2011-12-12T11:25:52","modified_gmt":"2011-12-12T10:25:52","slug":"nr-309-2011","status":"publish","type":"post","link":"https:\/\/www.astb.se\/cassiopeiabloggen\/2011\/12\/12\/nr-309-2011\/","title":{"rendered":"Nr 309 2011"},"content":{"rendered":"<h2>D\u00e4rf\u00f6r fick de Nobels fysikpris!<\/h2>\n<p>H\u00e4r f\u00f6ljer <a href=\"http:\/\/www.nobelprize.org\/nobel_prizes\/physics\/laureates\/2011\/presentation-speech_sv.html?print=1\">prof Olga Botners HELA presentationstal<\/a> fr\u00e5n Nobelfestligheterna i l\u00f6rdags:<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/images.jpeg\"><img decoding=\"async\" class=\"alignleft size-full wp-image-24587\" title=\"Tre glada fysikvinnare.\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/images.jpeg\" alt=\"\" width=\"148\" height=\"83\" \/><\/a><strong>Eders Majest\u00e4ter<\/strong>, Eders Kungliga H\u00f6gheter, mina damer och herrar.<\/p>\n<p><strong>Allow me to start<\/strong> in English by citing a short poem by the Danish scientist, poet and designer <strong>Piet Hein<\/strong>, called<em> Nothing is indispensable<\/em> \u2013 grook to warn the Universe against megalomania:<\/p>\n<p><em><strong>The Universe may<br \/>\nbe as big as they say.<br \/>\nBut &#8230; it wouldn&#8217;t be missed<br \/>\nif it didn&#8217;t exist!<\/strong><\/em><\/p>\n<p><strong>Well&#8230;Om universum <\/strong>inte fanns skulle vi definitivt inte sitta h\u00e4r idag!<\/p>\n<p><strong>M\u00e4nniskan \u00e4r en del av universum<\/strong> \u2013 precis som planeterna, stj\u00e4rnorna och galaxerna. Byggstenarna f\u00f6r varenda cell i v\u00e5ra kroppar \u2013 kol-, syre- och de andra atomerna \u2013 bildades inuti forntida stj\u00e4rnor som exploderade i Vintergatan f\u00f6r kanske 10 miljarder \u00e5r sedan, l\u00e5ngt innan solsystemet blev till, precis som de grund\u00e4mnen som planeterna bildats av. Galaxerna, stj\u00e4rnorna och planeterna p\u00e5verkas av samma naturkrafter som vi sj\u00e4lva \u2013 inte minst gravitationen som best\u00e4mmer planetbanorna och p\u00e5verkar stj\u00e4rnornas livscyklar &#8211; och ser till att vi har f\u00f6tterna p\u00e5 jorden. F\u00f6r att f\u00f6rst\u00e5 oss sj\u00e4lva m\u00e5ste vi f\u00f6rs\u00f6ka f\u00f6rst\u00e5 universum!<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/milkyway.gif\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24570\" title=\"Vintergatan - Lundapanoramat.\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/milkyway-300x161.gif\" alt=\"\" width=\"300\" height=\"161\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/milkyway-300x161.gif 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/milkyway.gif 1011w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong>\u00c5rets Nobelpris i fysik<\/strong> handlar just om stj\u00e4rnexplosioner och om gravitation \u2013 ja, faktiskt om hela universum.<\/p>\n<p><strong>Genom att observera<\/strong> avl\u00e4gsna galaxer med hj\u00e4lp av teleskop kom man redan f\u00f6r n\u00e4stan 100 \u00e5r sedan p\u00e5 att v\u00e5rt universum blir allt st\u00f6rre. Avst\u00e5nden mellan galaxerna \u00f6kar st\u00e4ndigt, ungef\u00e4r som avst\u00e5nden mellan russinen i en j\u00e4sande kaksmet. R\u00e4knar vi bak\u00e5t i tiden inser vi att expansionen m\u00e5ste ha haft sin b\u00f6rjan f\u00f6r cirka 14 miljarder \u00e5r sedan \u2013 i en urexplosion som den brittiske astrofysikern <strong>Fred Hoyle<\/strong> kallat Big Bang.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/250px-Fred_Hoyle.jpg\"><img decoding=\"async\" class=\"aligncenter size-full wp-image-24576\" title=\"Hoyle &quot;uppfann&quot; Big Bang\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/250px-Fred_Hoyle.jpg\" alt=\"\" width=\"250\" height=\"250\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/250px-Fred_Hoyle.jpg 250w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/250px-Fred_Hoyle-150x150.jpg 150w\" sizes=\"(max-width: 250px) 100vw, 250px\" \/><\/a><\/p>\n<p><strong>Under de senaste 5 miljarderna<\/strong> \u00e5r, ungef\u00e4r sedan solsystemet bildades, har universum f\u00f6rdubblats i storlek, och det forts\u00e4tter att utvidgas. Men \u2013 all materia i universum dras till all annan materia p.g.a. gravitationen. Avst\u00e5nden mellan galaxerna borde inte kunna forts\u00e4tta \u00f6ka lika fort i all evighet \u2013 expansionen borde s\u00e5 sm\u00e5ningom sakta in.\u00a0 Man kan r\u00e4kna ut att om universum inneh\u00e5ller mer \u00e4n sex atomer per kubikmeter s\u00e5 m\u00e5ste utvidgningen stanna av. Universum borde b\u00f6rja krympa och s\u00e5 sm\u00e5ningom sluta i en Big Crunch, motsatsen till Big Bang. \u00c4r detta universums \u00f6de?<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/FG26_005.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24572\" title=\"Universums expansion.\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/FG26_005-300x200.jpg\" alt=\"\" width=\"300\" height=\"200\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/FG26_005-300x200.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/FG26_005.jpg 600w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong>F\u00f6r att besvara den fr\u00e5gan<\/strong> m\u00e5ste man unders\u00f6ka om expansionshastigheten \u00e4ndras med tiden. Tursamt nog har vi tillg\u00e5ng till en &#8220;tidsmaskin&#8221;: Det ljus som n\u00e5r v\u00e5ra teleskop fr\u00e5n avl\u00e4gsna stj\u00e4rnor har f\u00e4rdats genom rymden under miljoner t.o.m. miljarder av \u00e5r, och blivit allt r\u00f6dare efterhand, d\u00e5 sj\u00e4lva rummet expanderat.<\/p>\n<p><strong>Om vi j\u00e4mf\u00f6r de uppm\u00e4tta<\/strong> r\u00f6df\u00f6rskjutningarna f\u00f6r m\u00e5nga olika objekt med de m\u00e5nga modeller f\u00f6r det expanderande universum som <strong>Einsteins<\/strong> allm\u00e4nna relativitetsteori till\u00e5ter, kan vi uppt\u00e4cka den modell som beskriver det verkliga universum. R\u00f6df\u00f6rskjutningarna kan tolkas som avst\u00e5nd, men tolkningen beror p\u00e5 modellernas olika antaganden om balansen mellan skilda energiformer t.ex. m\u00e4ngden str\u00e5lning och materia.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/20061007165757Schema_Redshift.png\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24583\" title=\"R\u00f6df\u00f6rskjutning f\u00f6rklaras.\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/20061007165757Schema_Redshift-300x82.png\" alt=\"\" width=\"300\" height=\"82\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/20061007165757Schema_Redshift-300x82.png 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/20061007165757Schema_Redshift-1024x281.png 1024w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/20061007165757Schema_Redshift.png 1111w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong>Om vi kan j\u00e4mf\u00f6ra dessa <\/strong>modellberoende avst\u00e5nd med andra, oberoende, avst\u00e5ndsm\u00e4tningar p\u00e5 samma objekt \u2013 kan vi fastst\u00e4lla energibalansen i universum. Men d\u00e5 beh\u00f6ver vi objekt som syns \u00f6ver enorma avst\u00e5nd \u2013 ljusk\u00e4llor vars ljus f\u00e4rdats \u00f6ver miljarder av \u00e5r.<br \/>\n<strong><br \/>\nForskarna som idag bel\u00f6nas<\/strong> med Nobelpriset i fysik studerar avl\u00e4gsna stj\u00e4rnexplosioner \u2013 supernovor. Dessa skeenden frig\u00f6r enorma m\u00e4ngder energi &#8211; en enda supernova kan under n\u00e5gra veckor \u00f6vergl\u00e4nsa alla de hundra miljarderna stj\u00e4rnorna i en galax!\u00a0 Stj\u00e4rnor kan slitas s\u00f6nder p\u00e5 m\u00e5nga olika s\u00e4tt, men det visar sig att det i speciella fall uppst\u00e5r explosioner som alltid skickar ut lika mycket ljus. Dessa explosioner kan k\u00e4nnas igen genom att noggrant studera det observerade stj\u00e4rnljuset. D\u00e5 m\u00e4ngden ljus som frig\u00f6rs alltid \u00e4r densamma kan man fr\u00e5n den observerade ljusstyrkan best\u00e4mma avst\u00e5ndet. Ju svagare ljus \u2013 desto l\u00e4ngre bort \u00e4r supernovan!<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/SN-2006gy.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24573\" title=\"Supernova briserar - SN 2006gy\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/SN-2006gy-300x245.jpg\" alt=\"\" width=\"300\" height=\"245\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/SN-2006gy-300x245.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/SN-2006gy.jpg 306w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong>Men universum \u00e4r stort,<\/strong> och att hitta r\u00e4tt sorts supernovor \u00e4r en utmaning f\u00f6r forskarna. Pristagarna och deras forskargrupper anv\u00e4nde digital teknik, och uppfann effektiva metoder f\u00f6r att avs\u00f6ka omr\u00e5den p\u00e5 himlavalvet upprepade g\u00e5nger och j\u00e4mf\u00f6ra tusentals bilder. Tiotals supernovor uppt\u00e4cktes, och med hj\u00e4lp av v\u00e4rldens st\u00f6rsta teleskop kunde sedan deras typ och ljusstyrka best\u00e4mmas, liksom det avst\u00e5nd som ges av r\u00f6df\u00f6rskjutningen.<\/p>\n<p><strong>Till allas oerh\u00f6rda f\u00f6rv\u00e5ning verkade<\/strong> supernovorna lysa alldeles f\u00f6r svagt! Svagare \u00e4n v\u00e4ntat om universums expansion saktat in. Universum verkar i st\u00e4llet ha utvidgat sig allt snabbare!<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/56200main_dark_expansion-lg.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24585\" title=\"Universum expanderar - fortare och fortare! \" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/56200main_dark_expansion-lg-300x198.jpg\" alt=\"\" width=\"300\" height=\"198\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/56200main_dark_expansion-lg-300x198.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/56200main_dark_expansion-lg.jpg 608w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><br \/>\n<strong><br \/>\nVad \u00e4r det d\u00e5 som f\u00e5r expansionstakten<\/strong> att \u00f6ka? Svaret skulle kunna vara: en s\u00e4rskild form av energi, kallad m\u00f6rk energi, som trycker universum &#8220;ut\u00e5t&#8221;. En liknande energiform \u2013 den kosmologiska konstanten \u2013 diskuterades av <strong>Einstein<\/strong> redan \u00e5r 1917 men f\u00f6rpassades sedan fr\u00e5n teorin. Den m\u00f6rka energin tycks utg\u00f6ra cirka 73% av all energi i universum vilket under det senaste decenniet bekr\u00e4ftats av galaxernas f\u00f6rdelning \u00f6ver stora avst\u00e5nd och av studier av den kosmiska bakgrundsstr\u00e5lningen.<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/dark-energy.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24577\" title=\"M\u00f6rk energi dominerar i v\u00e5rt universum.\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/dark-energy-276x300.jpg\" alt=\"\" width=\"276\" height=\"300\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/dark-energy-276x300.jpg 276w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/dark-energy.jpg 530w\" sizes=\"(max-width: 276px) 100vw, 276px\" \/><\/a><br \/>\n<strong><br \/>\nUppt\u00e4ckten av den accelererande expansionen<\/strong> genom studier av avl\u00e4gsna supernovor har allts\u00e5 p\u00e5 ett ov\u00e4ntat och dramatiskt s\u00e4tt f\u00f6r\u00e4ndrat v\u00e5r bild av universum. Vi har insett att vi lever i ett universum som till st\u00f6rsta delen best\u00e5r av komponenter som vi inte k\u00e4nner till.\u00a0 Att f\u00f6rst\u00e5 sig p\u00e5 den m\u00f6rka energin \u00e4r en utmaning f\u00f6r forskare v\u00e4rlden \u00f6ver \u2013 allt enligt <strong>Piet Heins <\/strong>devis:<\/p>\n<p><em><strong>Problems worthy of attack<br \/>\nprove their worth by hitting back.<\/strong><\/em><\/p>\n<p>Professor <strong>Perlmutter<\/strong>, Professor <strong>Schmidt<\/strong>, Professor <strong>Riess<\/strong>,<\/p>\n<p><a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/large-nobel-chemistry-medal.jpg\"><img decoding=\"async\" class=\"aligncenter size-medium wp-image-24580\" src=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/large-nobel-chemistry-medal-300x152.jpg\" alt=\"\" width=\"300\" height=\"152\" srcset=\"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/large-nobel-chemistry-medal-300x152.jpg 300w, https:\/\/www.astb.se\/cassiopeiabloggen\/wp-content\/uploads\/2011\/12\/large-nobel-chemistry-medal.jpg 800w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>You have been awarded the Nobel Prize in Physics for the discovery of the accelerating expansion of the Universe through observations of distant supernovae. On behalf of the Royal Swedish Academy of Sciences it is my honour and my pleasure to convey to you the warmest congratulations.\u00a0 I now ask you to step forward to receive your Nobel Prize from the hands of <strong>His Majesty the King<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>D\u00e4rf\u00f6r fick de Nobels fysikpris! H\u00e4r f\u00f6ljer prof Olga Botners HELA presentationstal fr\u00e5n Nobelfestligheterna i l\u00f6rdags: Eders Majest\u00e4ter, Eders Kungliga H\u00f6gheter, mina damer och herrar. Allow me to start in English by citing a short poem by the Danish scientist, poet and designer Piet Hein, called Nothing is indispensable \u2013 grook to warn the Universe&hellip;&nbsp;<a href=\"https:\/\/www.astb.se\/cassiopeiabloggen\/2011\/12\/12\/nr-309-2011\/\" rel=\"bookmark\">L\u00e4s mer &raquo;<span class=\"screen-reader-text\">Nr 309 2011<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rop_custom_images_group":[],"rop_custom_messages_group":[],"rop_publish_now":"initial","rop_publish_now_accounts":[],"rop_publish_now_history":[],"rop_publish_now_status":"pending","neve_meta_sidebar":"","neve_meta_container":"","neve_meta_enable_content_width":"","neve_meta_content_width":0,"neve_meta_title_alignment":"","neve_meta_author_avatar":"","neve_post_elements_order":"","neve_meta_disable_header":"","neve_meta_disable_footer":"","neve_meta_disable_title":"","footnotes":""},"categories":[3],"tags":[],"_links":{"self":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/24568"}],"collection":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/comments?post=24568"}],"version-history":[{"count":18,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/24568\/revisions"}],"predecessor-version":[{"id":24595,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/posts\/24568\/revisions\/24595"}],"wp:attachment":[{"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/media?parent=24568"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/categories?post=24568"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.astb.se\/cassiopeiabloggen\/wp-json\/wp\/v2\/tags?post=24568"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}