Ekuseni kakhulu indawo yonke, ngokushesha ngemva kwe-Big Bang, 'ndaba' kanye 'ne-antimatter' zombili bezikhona ngenani elilinganayo. Kodwa-ke, ngenxa yezizathu ezingaziwa kuze kube manje, 'ndaba' ibusa okwamanje indawo yonke. Abacwaningi be-T2K basanda kukhombisa ukwenzeka kokwephulwa kwe-Charge-Parity okungenzeka kube khona ku-neutrino kanye nama-oscillations e-anti-neutrino ahambisanayo. Lesi isinyathelo esiya phambili ekuqondeni ukuthi kungani ndaba ibusa i indawo yonke.
I-Big Bang (eyenzeka eminyakeni eyizigidi eziyizinkulungwane ezingu-13.8 edlule) kanye neminye imibono ehlobene ye-physics iphakamisa ukuthi indawo yonke kwakuyi-radiation 'dominant' futhi 'ndaba'futhi'antimatter' ibikhona ngenani elilinganayo.
Kodwa i indawo yonke esikwaziyo namuhla 'kuyindaba' ebusayo. Kungani? Lena enye yezimfihlakalo ezithakazelisa kakhulu indawo yonke. (I-1).
The indawo yonke esaziyo namuhla ukuthi ziqale ngamanani alinganayo 'wezinto' kanye 'ne-antimatter', zombili zidalwe ngazimbili njengoba umthetho wemvelo ubungadinga futhi zaqedwa ngokuphindaphindiwe zikhiqiza imisebe eyaziwa ngokuthi 'imisebe engemuva kwe-cosmic'. Phakathi nemizuzwana emincane eyi-100 ye-Big Bang udaba (izinhlayiya) ngandlela thize zaqala ukudlula inhlayiya ephikisana nezinhlayiya ngenani elilodwa ebhiliyoni ngalinye futhi emizuzwaneni yonke i-antimatter yacekelwa phansi, kwasala izinto kuphela.
Iyiphi inqubo noma indlela engadala lolu hlobo lomehluko noma i-asymmetry phakathi kwendaba ne-antimatter?
Ngo-1967, isazi sefilosofi saseRussia u-Andrei Sakharov sabeka izimo ezintathu ezidingekayo ukuze ukungalingani (noma ukukhiqizwa kwento ne-antimatter ngamanani ahlukene) kwenzeke indawo yonke. Isimo sokuqala se-Sakharov yinombolo ye-baryon (inombolo ye-quantum ehlala igcinwe ekusebenzisaneni) ukwephulwa. Kusho ukuthi ama-proton abola kancane kancane aba yizinhlayiya ezilula njenge-pion engathathi hlangothi kanye ne-positron. Ngokufanayo, i-antiproton yabola yaba i-pion ne-electron. Umbandela wesibili ukwephulwa kwe-charge conjugation symmetry, C, kanye ne-charge conjugation-parity symmetry, i-CP ebizwa nangokuthi ukwephulwa kwe-Charge-Parity. Umbandela wesithathu ukuthi inqubo ekhiqiza i-baryon-asymmetry akumele ilingane ngokushisa okushisayo ngenxa yokwanda okusheshayo okwehlisa isenzeko sokubhangqwana.
Kuyisici sesibili sikaSakharov sokuphulwa kwe-CP, okuyisibonelo sohlobo lwe-asymmetry phakathi kwezinhlayiya nama-antiparticles azo achaza indlela ezibola ngayo. Ngokuqhathanisa indlela izinhlayiya nama-antiparticles aziphatha ngayo, okungukuthi, indlela ezihamba ngayo, ezisebenzelana ngayo, nokubola, ososayensi bangathola ubufakazi balokho asymmetry. Ukwephulwa kwe-CP kunikeza ubufakazi bokuthi ezinye izinqubo ezibonakalayo ezingaziwa zinesibopho sokukhiqiza okuhlukile kwezinto ne-antimatter.
I-electromagnetic kanye 'nokusebenzelana okuqinile' kwaziwa njengokulinganayo ngaphansi kuka-C no-P, futhi ngenxa yalokho kuphinde futhi ku-symmetric ngaphansi komkhiqizo we-CP (3). ''Kodwa-ke, lokhu akunjalo 'ngokusebenzisana okubuthakathaka', okwephula kokubili ukulinganisa kuka-C no-P'' kusho uProf BA Robson. Uqhubeka athi “ukwephulwa kwe-CP ekusebenzelaneni okubuthakathaka kusho ukuthi izinqubo ezinjalo zomzimba zingaholela ekwephulwani okungaqondile kwenombolo ye-baryon ukuze ukudalwa kwezinto kuzokhethwa kunokudalwa kwe-antimatter''. Izinhlayiya ezingezona ze-quark azibonisi noma yikuphi ukwephulwa kwe-CP kuyilapho ukwephulwa kwe-CP kuma-quarks kukuncane kakhulu futhi akubalulekile ukuba nomehluko ekudalweni kwezinto kanye ne-antimatter. Ngakho-ke, ukwephulwa kwe-CP kuma-leptons (neutrinos) kubaluleke kakhulu futhi uma kufakazelwa kuzophendula ukuthi kungani indawo yonke yindaba ebusayo.
Nakuba ukwephulwa kokulinganisa kwe-CP kusazofakazelwa ngokuphelele (1) kodwa okutholakele okubikwe yithimba le-T2K muva nje kubonisa ukuthi ososayensi baseduze kakhulu nakho. Kuye kwaboniswa okokuqala ukuthi ukuguquka kusuka kuyizinhlayiyana kuya ku-electron ne-neutrino kukhethwa ngaphezu kokuguqulwa kusuka ku-antiparticle kuya ku-electron ne-antineutrino, ngokuhlolwa okuyinkimbinkimbi kakhulu ku-T2K (i-Tokai kuya ku-Kamioka) (2). I-T2K ibhekisela kulabhorethri, i-Japanese Proton Accelerator Research Complex (J-Parc) thathaka kanye ne-Super-Kamiokande underground neutrino observatory in the Kamioka, Japan, ehlukaniswe cishe 300 km. I-accelerator ye-proton e-Tokai ikhiqize izinhlayiya nama-antiparticles kusuka ekungqubuzaneni kwamandla aphezulu kanye nezitholi e-Kamioka zabona ama-neutrino nozakwabo be-antimatter, ama-antineutrino ngokwenza izilinganiso ezinembe kakhulu.
Ngemva kokuhlaziywa kweminyaka eminingana yedatha ku-T2K, ososayensi bakwazi ukukala ipharamitha ebizwa ngokuthi i-delta-CP, elawula ukulinganisa kwe-CP ekuqhekekeni kwe-neutrino futhi bathola ukungafani noma okuthandwayo kokuthuthukisa izinga le-neutrino elingagcina liholele ekutheni ukuqinisekiswa kokwephulwa kwe-CP ngendlela i-neutrinos nama-antiutrinos oscillated. Imiphumela etholwe ithimba le-T2K ibalulekile ngokubaluleka kwezibalo okungu-3-sigma noma 99.7%. Kuyimpumelelo eyingqopha-mlando njengoba ukuqinisekiswa kokwephulwa kwe-CP okubandakanya i-neutrinos kuxhunyaniswa nokubusa kwendaba indawo yonke. Ukuhlola okwengeziwe ngesizindalwazi esikhulu kuzohlola ukuthi ingabe lokhu kwephulwa kwe-leptonic CP symmetry kukhulu kunokwephulwa kwe-CP kuma-quarks. Uma kunjalo, ekugcineni sizoba nempendulo yombuzo othi Kungani indawo yonke yindaba ebusayo.
Nakuba ukuhlolwa kwe-T2K kungabonisi ngokucacile ukuthi ukwephulwa kokulinganisa kwe-CP kwenzekile kodwa kuyingqopha-mlando ngomqondo wokuthi kukhombisa ngokuphelele ukuthanda okunamandla kwenani le-electron neutron elithuthukisiwe futhi kusisondeza ukuze sifakazele ukwenzeka kokuphulwa kokulinganisa kwe-CP futhi ekugcineni phendula 'kungani indawo yonke yindaba ebusayo'.
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References:
1. Inyuvesi yaseTokyo, 2020. ''Imiphumela ye-T2K Ikhawulela Amanani Angenzeka ESigaba Se-Neutrino CP -…..'' Ukukhishwa Kwabezindaba Kushicilelwe ngomhla ka-16 Ephreli 2020. Itholakala ku-inthanethi kokuthi http://www.icrr.u-tokyo.ac.jp/en/news/8799/ Kufinyelelwe ngomhla ka-17 Ephreli 2020.
2. Ukusebenzisana kwe-T2K, 2020. Umkhawulo odabeni–isigaba sokwephulwa kwe-antimatter symmetry ku-oscillations ye-neutrino. Ivolumu yemvelo 580, amakhasi339–344(2020). Kushicilelwe: 15 Ephreli 2020. DOI: https://doi.org/10.1038/s41586-020-2177-0
3. Robson, BA, 2018. Inkinga ye-Matter-Antimatter Asymmetry. Ijenali ye-High Energy Physics, Gravitation and Cosmology, 4, 166-178. https://doi.org/10.4236/jhepgc.2018.41015
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