0:00:01.000,0:00:12.119 [music] 0:00:12.119,0:00:14.900 If you've had any interested in physics at all you've heard about a thing called the 0:00:14.900,0:00:16.990 Higgs boson. 0:00:16.990,0:00:19.859 But just what is it then why is it interesting? 0:00:19.859,0:00:24.060 In 1964 a physicist by the name of Peter Higgs 0:00:24.060,0:00:26.969 took some ideas that were floating around at the time, 0:00:26.969,0:00:30.899 added an insight or two of his own, and proposed that there was an energy field 0:00:30.899,0:00:33.400 that permeated the entire universe. 0:00:33.400,0:00:36.570 This energy field is now called the "Higgs field." 0:00:36.570,0:00:40.160 The reason he proposed this field was that nobody understood why some 0:00:40.160,0:00:43.220 subatomic particles had a great deal of mass 0:00:43.220,0:00:46.270 while others had little and some had none at all! 0:00:46.270,0:00:49.270 The energy field that Higgs proposed would interact 0:00:49.270,0:00:52.500 with the sub-atomic particles and give them their mass. Very massive particles 0:00:52.500,0:00:57.560 would interact a lot of the field while massless particles wouldn't interact at all. 0:00:57.560,0:01:02.050 To better understand the idea, we can use the analogy of water and swimmers. 0:01:02.050,0:01:05.089 In our analogy the water serves the role 0:01:05.089,0:01:06.390 of the Higgs field. 0:01:06.390,0:01:10.260 A barracuda, being supremely streamlined, interacts only slightly with 0:01:10.260,0:01:13.140 the field and can move through it very easily. 0:01:13.140,0:01:16.800 The barracuda would then be similar to a low-mass particle. 0:01:16.800,0:01:20.710 In contrast, my buddy Eddie, no stranger to doughnuts 0:01:20.710,0:01:23.510 can only move very slowly through the water. 0:01:23.510,0:01:28.120 In our analogy, Eddie is a massive particle made massive by interacting a lot with 0:01:28.120,0:01:29.430 the water. 0:01:29.430,0:01:33.759 The lightest of the familiar subatomic particles is the electron, while in the subatomic 0:01:33.759,0:01:36.810 world the king of mass is the top quark. 0:01:36.810,0:01:39.740 It weighs about as much as an entire atom of gold, 0:01:39.740,0:01:43.320 about three hundred and fifty thousand times more than the electron! 0:01:43.320,0:01:46.520 I'd like to stress that we believe the top quark is not more massive because 0:01:46.520,0:01:48.130 it's bigger. It's not! 0:01:48.130,0:01:52.490 In fact, we believe that both the top quark and the electron are exactly the same size! 0:01:52.490,0:01:55.700 Indeed, they both have zero size! 0:01:55.700,0:01:59.250 The top quark is more massive than the electron simply because it interacts 0:01:59.250,0:02:01.380 more with the Higgs field. Actually, 0:02:01.380,0:02:03.050 if the Higgs field didn't exist, 0:02:03.050,0:02:07.880 neither of these particles would have any mass at all! 0:02:07.880,0:02:09.229 Now, in the press 0:02:09.229,0:02:12.839 you don't hear about the Higgs field but rather the Higgs boson. 0:02:12.839,0:02:14.829 How are these two things related? 0:02:14.829,0:02:19.189 The Higgs boson is the smallest bit of the Higgs field. 0:02:19.189,0:02:23.029 To understand how that works we should again return to water. 0:02:23.029,0:02:25.139 Everyone knows what water is. 0:02:25.139,0:02:29.790 If you're immersed in it you know that water is everywhere. It's a continuous medium 0:02:29.790,0:02:31.949 and there are no holes in it. 0:02:31.949,0:02:37.849 We also know that water is made of molecules - specifically H20. 0:02:37.849,0:02:41.469 If you hold these two ideas in your head with the realization that water consists 0:02:41.469,0:02:44.819 of countless individual molecules you can now begin to appreciate 0:02:44.819,0:02:46.789 the Higgs boson. 0:02:46.789,0:02:51.139 The Higgs field that gives subatomic particles their mass is made of countless individual 0:02:51.139,0:02:55.709 Higgs bosons, just like water is made of individual molecules. 0:02:55.709,0:02:59.069 You should keep in mind that the Higgs boson hasn't been discovered yet, and 0:02:59.069,0:03:03.789 what I'm describing is simply the most popular idea as to why subatomic 0:03:03.789,0:03:07.159 particles have the masses that they do. 0:03:07.159,0:03:08.439 As I speak 0:03:08.439,0:03:12.669 my colleagues and I are studying data taken at huge particle accelerators to see if 0:03:12.669,0:03:15.000 this idea is true. 0:03:15.000,0:03:19.000 Stay tuned! 0:03:19.000,9:59:59.000 [music]