Science Newsletter #15 - Bournemouth School for Girls

MATTER’SEVIL TWINEver since the paper on it in 1928, antimatter hascaptured the thoughts of science fiction writers andfans alike. Yet it is a real substance that is pro-duced in small quantities every day! Dom reports.Anmaer e very word causes science con tospring to mind, rom rocet uels or te uture to‘flawless energy generaon et in tis case, anmaeris actually science act, predicted wit a proper sciencteory in 198 and proved 4 years later Its een descried as te most expensive sustance in te world; in te general esmate was tat million dollars could produce 1 milligrams o positrons Not tatanyone would actually sell anmaer to you, no maerow ric you are – its capaility or destrucon is anoter ting tat as made it amous Wen anmaercomes into contact wit normal maer, suc as te atoms in your ody, it anniilates it completely wit aurst o enormous energy – terell e more aout tatlater But ear not, people o Eart, anmaer weaponsare not someting well e seeing in te near uture owe can rest easyor nowhat actually is anmaer?But wat really is anmaer? Beore we can understandtat, we need to loo at ‘carge and ‘spin, two intrinsicproperes o suatomic parcles suc as te electronElectric carge is a property o maer tat causes it toexperience a orce wen near oter maer wit an electrical carge is is your ‘posive and ‘negave carge– same carges repel, wile lie carges aract Easy,rigt? pin is less simple In scienc terms, its an inerent orm o angular momentum carried y elementaryparcles, composite parcles, and atomic nuclei omae it a it easier to understand, picture a asetall rotang on a players nger It can rotatele to rigt, or rigt to le, on an axis perpendicular to te nger, wic in tis analogy could represent opposite spin Now tat were clear on teterminology, anmaer is virtually idencal tomaer, wit opposite carge and spin For example, te anparcle counterpart o te electron iste ‘positron, wic as a posive carge as itsname suggests e act tat it is very similar tomaer as led to speculaon tat tere could esomewere tat is made enrely o anmaer,wit an anyou tat youd really not want tomeet! In act, te only reason our maer is‘maer is ecause in our universe tere seems toe a sortage o anmaer, so we named wat iscommon to us rsthy do maer and anmaer annihilate?I you and your anyou were to sae ands, allell would rea loose As a general rule o parcle pysics even tougt tere are some excepons), tings lie to decay into oter tings tatave as small a mass as possile is is wy eavier parcles suc as muons decay witin a racono a second Wen an anparcle and a parcleanniilate, tey produce potons, wic aremassless is is te ulmate state to acieve orparcles tat are ale to decay An electron on itsown can't simply decay into potons as carge is