Higgs Boson: The Inside Scoop

[Music] for Americans July 4th is the day for fireworks however in 2012 the most exciting pyrot Technics were of a scientific rather than the incendiary variety rather than gathering with family for cookouts and Parks across the country physicists either gathered in an auditorium at the C laboratory or at least watched the excitement V live video feed a new discovery was the anticipated one over 50 years in the making in 1964 three scientific Papers written by six different physicists proposed a previously unsuspected energy field in the universe while he was not the only Keen mind who had the idea this new energy field is now called the higs field after Dr Peter higs technically what scientists claimed in July of 2012 was that a new particle had been discovered in order to understand whether the new particle was the higs Bon or not researchers performed several tests to see if the new particle had the right properties while every test that was performed showed that the new discovery acted like the higs boson was predicted to act there were many properties that hadn't been tested if CERN had discovered a new fruit the report would be that the new fruit looked and smelled like an apple but nobody had touched tasted or listened to it yet so what was claimed was the magic phrase the newly discovered particle is consistent with being the higs bozone all tested properties supported the claim but more tests were needed to make a definitive claim so what has happened in the intervening months well the first thing is that we collected a lot more data not sweating what the units mean in July of 2012 we had about 10 units of data and now we have 25 this increase in data means that we can remeasure the things studied last last year with improved Precision however in addition to improving existing measurements we can study new properties since the higs boson was predicted from a theory all of its properties were completely specified for instance some of its expected qualities are that it be electrically neutral have a spin of zero a positive parity and have nothing inside of it in March of 2013 LHC scientists released the results of improved analyses we we measured the various ways a higs boson can be made and the many ways in which it can decay all measurements were statistically consistent with predictions the phrase statistically consistent means that while the measurements weren't exactly as predicted they were as close as could be expected for the amount of data collected these measurements were improvements over the results of July 2012 but were basically the same thing however two new measurements were also made the first was the spin of the new particle from the patterns observed in 2012 we knew that the new particle had to have either a spin of zero or two it might be hard to imagine how you would measure the spin of a subatomic particle but it's easy to understand how you would do it in principle if a particle has a spin of zero that means it isn't spinning if you think of an isolated particle in empty space just sitting there there is nothing that makes One Direction different from any other direction left is the same as up is the same as the direction pointing at CERN if there is nothing to pick a particular direction then there is nothing to tell the Decay products where to go thus they will Decay with equal probability in all directions sometimes this way and sometimes that in contrast if a particle has a spin of two then there is an axis the particle is spinning around this picks a special Direction because of this and because the Decay products themselves have a spin it means that the Decay products won't go in all directions with equal probability there will be a specific pattern with some directions happening more often so this was easy when we checked the directions we found that all directions occurred with equal probability a spin zero particle was highly favored since the higs boson is predicted to have a spin of zero this is additional support that higs boson has been found another property that is harder to understand is the idea of parity parody is when you ask what happens when you swap left with right up with down and forward with backward can you tell the difference as an illustration we see a simplified version of parity here when you swap just left and right if when you swap the two it doesn't look very different this is positive parity if when you swap the two it looks just the opposite then this is negative parity when we studied the data to see which sort of parity the new particle had we found that it had positive parity this is the same parity that the higsbo is predicted to have thus we have another supporting bit of information suggesting that the new particle might be a higs boson in fact most scientists are now willing to say that we have found a higs bosan now you might have noticed that I keep saying a higs boson and not the higs boson what's up with that the problem is that while the standard model predicts a single higs boson there are other newer theories that predict more than one thus in order to be certain that we found the higs boson of the standard model we needed to establish that there aren't other undiscovered higs bosons out there that will take some time in fact it may will require that we take a lot more data and the final answer will have to wait until the LHC resumes operations in early 2015 while the researchers will do their best to squeeze out the last bit of information from this data it may be that we'll all have to be patient oh you might have been wondering about this shirt it it is true that I'm a member of one of the collaborations that discovered the higs Bon somehow my mom got the idea that I did it all myself so she bought it for me actually this discovery took two experiments with over 6,000 physicists if you include the accelerator scientists the number is more like 10,000 and we remember that the effort has taken about 20 years the real number of people it took to find the higs bow on is probably double that or even more in fact if you're watching this there's a good chance that your country's science department or Ministry contributed funds to the effort when you get right down to it the discovery of the higs bone has really been a scientific Triumph in which all of humanity can take some credit but you know since we're friends and all i' really appreciate it if you don't tell my mom she's been bragging to her bridge club and well you'll understand thanks [Music]

Channel: Fermilab

Views: 130,315

Keywords: proof, metaphor, scientist, Large Hadron Collider, fermilab, CMS, example, Higgs Boson, ian krass, current status, learn, mass, Don Lincoln, educational, CERN, particle, LHC, Physics, Higgs, discovery, physicist, explained, Higgs Field, don lincoln, funny, Fermilab, physics, Atlas, science, fireworks, fourth of july, july 4, 1964, papers, energy field, tests, apple, closeup, study, theory, proven, netural, spin, july 2012, 2013, measurement, parity, positive, negative, standard model, undiscovered, answer, international

Id: CwMq_xqif8k

Length: 6min 58sec (418 seconds)

Published: Fri Aug 09 2013