http___www.jutarnji.hr_life_znanost_pronaden-higgsov-bozon-zasto-je-ovo-najvaznije-otkrice-u-modernoj-fizici_1372959__1.xml
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The European Organization for Nuclear Research (CERN) announced at a conference early Wednesday morning that they have evidence to support the existence of the Higgs boson and are on their way to a major scientific breakthrough. While the existence of the Higgs boson — the fundamental particle of the hypothetical Higgs field that explains why some particles have mass and others do not — was not definitively proven at the conference, CERN’s highly anticipated report on the findings from its two experiments, ATLAS and CMS, showed a particle that could be proven to be the Higgs boson after further testing. Lawrence Berkeley National Laboratory researchers contributed to the ATLAS experiment. Joe Incandela, CMS spokesperson and UC Santa Barbara physics professor, described the breakthrough discovery of a new particle that could be the Higgs boson in his presentation at the conference. “This historic milestone is only the beginning,” said CERN director Rolf Heuer to cap the presentation. “It has global implications for the future.” Ian Hinchliffe, senior physicist at the Berkeley Lab and head of the the lab’s participation in ATLAS, said CERN will need much more detail on the properties of the Higgs boson to prove its existence. The organization will test the properties of the Higgs boson outlined in the Standard Model, the well-tested 20th century theory that most physicists today believe describes the fundamental particle. CERN will also continue to collect data using the Large Hadron Collider — a particle accelerator with a 27-kilometer circumference on the Swiss-French border near Geneva and the testing site for ATLAS and CMS — in order to accumulate the data necessary to more exactly determine the Higgs boson, according to Incandela. The experiments will also continue to increase the amount of data they collect, according to Hinchliffe. “Imagine (the Higgs field) like honey or molasses,” said Beate Heinemann, Berkeley Lab scientist and campus physics professor. “Instead of it just being some random molasses, it’s a lot of little Higgs (boson) particles.” According to Heinemann, if a particle is slowed down by the Higgs field, it has mass, but if it is not slowed down by the Higgs field, it has no mass. The Berkeley Lab has been extensively involved with the ATLAS experiment, representing one of the largest U.S. contingents with 40 students and postdoctorates working in Geneva, according to Hinchliffe. The lab developed the pixel detector, which serves as the innermost layer of the collider that accurately tracks the particles, designed the software that detects the more interesting collisions and has helped build and operate the ATLAS detector. “It’s always a very stimulating environment with so many intelligent people around you … to have your ideas questioned by very smart people while you’re questioning the ideas of other very smart people from around the world,” Hinchliffe said. Although there are currently no hypotheses for practical applications for the Higgs boson, its discovery could provide the foundation for a larger understanding of physics and the universe, according to Paul Preuss, a science writer at the Berkeley Lab’s public affairs office. “It’s really the keystone to how we understand how the world works,” Pruess said. “It’s a beginning point for where we can explore down other fascinating corridors to find extra dimensions of space, or miniature black holes, or find out what dark matter is made of or any more future unknowns.”
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ZAGREB - Naše aktualno razumijevanje fizike čestica počiva na Standardnom Modelu, razvijenom u sedamdesetim godinama prošlog stoljeća, koji je uspješno opisao sve elementarne čestice poznate u to vrijeme, i odnose među njima. Standardni model također je predviđao postojanje i čestica koje do tada još nisu bile opažene, poput b kvarka, t kvarka i tau neutrina. Rolf Heuer, generalni direktor CERN-a: Mislim da ga imamo. Imamo otkriće! Standardni model također je predviđao i postojanje Higgsovog bozona, čestice čija je teoretska razina energije bila iznad razine koju su ljudi mogli postići u akceleratorima čestica prije pokretanja LHC-a. Ukoliko Higgsov bozon ne bi bio pronađen, to bi značilo da postoje funtamentalne pogreške u Standardnom Modelu, te da je potrebna nova teorija fizike čestica koja bi objasnila zašto čestice imaju masu. Otkriće Higgsovog bozona, s druge strane, konačna je potvrda znanstvenicima da Standardni Model točno opisuje svijet koji nas okružuje. Standardni Model Prema Standardnom Modelu, sve čestice su ili fermioni, od kojih se sastoji sva materija, ili bozoni, koji služe kao nositelji sile. Fermioni su kvarkovi, koji sačinjavaju 'klasične' subatomske čestice poput protona i neutrona, te leptoni, poput elektrona ili neutrina. Standardni Model matematički je predvidio postojanje šest kvarkova - u, c, t, d, s i b, čije je postojanje i eksperimentalno potvrđeno, te šest leptona - elektron, muon, tau, elektron neutrino, muon neutrino i tau neutrino. Eksperimentalno je potvrđeno i postojanje četiri bozona - fotona, koji prenosi informacije o elektromagnetskoj sili, gluona, koji djeluje na kvarkove i prenosi informacije o jakoj nuklearnoj sili, te W i Z bozona, koji prenose informacije o slaboj nuklearnoj sili. Higgsov bozon, prema Standardnom Modelu, djeluje na druge čestice te im 'daje' masu - tj. interakcija između Higgsovog bozona i drugih čestica određuje kolika je njihova masa. Jedina preostala neotkrivena čestica Standardnog Modela je graviton, kojeg vjerojatno nikada neće biti moguće izravno eksperimentalno potvrditi, zbog njegove iznimno slabe interakcije sa svim drugim poznatim česticama. No, otkriće Higgsovog bozona nedvosmisleno je potvrdilo ispravnost teorije Standardnog Modela, te možemo biti gotovo sigurni kako i gravitoni postoje.