WEBVTT 00:00:00.000 --> 00:00:03.600 The simple questions are the hardest ones to answer. 00:00:03.600 --> 00:00:04.860 What is a thing? 00:00:04.860 --> 00:00:06.660 Why do things happen? 00:00:06.660 --> 00:00:09.380 And why DO they happen the way they do? 00:00:09.380 --> 00:00:11.700 Let's try to approach this step by step. 00:00:11.700 --> 00:00:13.600 What are you made of? 00:00:13.600 --> 00:00:15.000 You are matter, 00:00:15.000 --> 00:00:16.520 which is made of molecules, 00:00:16.520 --> 00:00:17.660 which are made of atoms, 00:00:17.660 --> 00:00:20.500 and those are made of elementary particles. 00:00:20.500 --> 00:00:24.740 But, if elementary particles are the smallest things that exist, 00:00:24.740 --> 00:00:26.740 What are THEY made of? 00:00:35.200 --> 00:00:38.380 To answer a simple question, let's start simply. 00:00:38.380 --> 00:00:40.680 Let's wipe the universe clean. 00:00:40.680 --> 00:00:45.380 Away with matter, antimatter, radiation, particles, anything. 00:00:45.380 --> 00:00:49.140 Now let's take a closer look at absolutely nothing. 00:00:49.140 --> 00:00:51.180 What is empty space? 00:00:51.180 --> 00:00:53.180 Is it what we call a vacuum? 00:00:53.180 --> 00:00:56.240 There are no atoms, no matter, nothing! 00:00:56.240 --> 00:00:58.460 Is it really all that empty? 00:00:58.460 --> 00:01:02.100 Nothing gives us the building blocks for everything. 00:01:02.100 --> 00:01:06.380 In a sense, empty space is a lot like a vast, calm ocean. 00:01:06.380 --> 00:01:09.240 While the water is very still when nothing is happening, 00:01:09.240 --> 00:01:12.539 a stiff breeze can create some serious waves. 00:01:12.540 --> 00:01:14.660 Our universe works a lot like this. 00:01:14.660 --> 00:01:16.880 There are these oceans everywhere. 00:01:16.880 --> 00:01:19.420 Physicists call them fields. 00:01:19.420 --> 00:01:21.000 This might be strange and new, 00:01:21.000 --> 00:01:23.560 but think about radiation for example. 00:01:23.560 --> 00:01:28.140 By exciting what's known as the electromagnetic field, a little kink is created 00:01:28.140 --> 00:01:30.240 which is the particle we call the photon. 00:01:30.240 --> 00:01:34.140 The particle that carries radiation, we perceive it as light. 00:01:34.140 --> 00:01:38.920 This isn't unique to light; every particle in the universe is made this way. 00:01:38.920 --> 00:01:43.460 There are fields for every particle of matter all with their own rules. 00:01:43.460 --> 00:01:48.619 For example, along with the electromagnetic field, there is an electron field everywhere in the universe 00:01:48.620 --> 00:01:51.700 and little kinks in that field are electrons. 00:01:51.700 --> 00:01:58.360 All together, the fields of our universe can produce 17 particles which can be divided into 3 categories. 00:01:58.360 --> 00:02:02.120 The leptons, and the quarks, and the bosons. 00:02:02.120 --> 00:02:07.420 Leptons consist of the electron as well as its cousins: muon and tau particles. 00:02:07.420 --> 00:02:10.000 Each has an associated neutrino. 00:02:10.000 --> 00:02:11.780 Then, there are quarks. 00:02:11.780 --> 00:02:14.540 The quarks are the nuclear family of particles. 00:02:14.540 --> 00:02:17.600 They're always found bound together in groups and pairs 00:02:17.600 --> 00:02:21.360 and make up protons and neutrons, which make up the nuclei of atoms. 00:02:21.360 --> 00:02:24.620 Together, the leptons and quarks are the matter particles. 00:02:24.620 --> 00:02:26.520 They make up all the things you see. 00:02:26.520 --> 00:02:28.980 The air you breathe, the sun that warms you, 00:02:28.980 --> 00:02:33.260 the computer you're using right now to distract yourself from the stuff you should be doing. 00:02:33.260 --> 00:02:36.720 But things don't just exist, they also do stuff. 00:02:36.720 --> 00:02:42.940 In some philosophical sense, the properties of a thing are just as much a part of it as existence itself. 00:02:42.940 --> 00:02:46.720 This is where the bosons and the fields that makes them come in to play. 00:02:46.720 --> 00:02:49.680 While the quarks and leptons are made by the matter fields, 00:02:49.680 --> 00:02:52.480 the bosons are made by force fields. 00:02:52.480 --> 00:02:55.200 We call a rule of the universe a force. 00:02:55.200 --> 00:02:58.679 And so far, 4 fundamental forces have been discovered: 00:02:58.680 --> 00:03:03.640 Electromagnetism, gravity, and the strong and weak nuclear forces. 00:03:03.640 --> 00:03:09.440 These forces are the rule book of a game where the pieces are the particles, and the game is the universe. 00:03:09.440 --> 00:03:13.100 They tell particles what they can do and how they can do it. 00:03:13.100 --> 00:03:14.840 Bishops move diagonally, 00:03:14.840 --> 00:03:17.300 massless particles move at the speed of light, 00:03:17.300 --> 00:03:18.720 knights can jump, 00:03:18.720 --> 00:03:20.480 gravity attracts. 00:03:20.480 --> 00:03:23.619 The forces are the rules for how particles interact 00:03:23.620 --> 00:03:29.480 Which ultimately make them the rules for how particles assemble into all the big things we see in the universe. 00:03:29.480 --> 00:03:34.440 Gravity isn't just the rule for orbits around the sun or apples falling from trees. 00:03:34.440 --> 00:03:39.240 As a rule, it says matter attracts, which builds planets and stars. 00:03:39.240 --> 00:03:45.640 Electromagnetism isn't just the rule for magnets attracting or repelling, or electric currents in light bulbs. 00:03:45.640 --> 00:03:49.940 It governs all atomic bonds, building every molecule. 00:03:49.940 --> 00:03:55.200 Together, forces and particles are sort of like the Tinkertoys of existence. 00:03:55.200 --> 00:04:00.100 The bosons are like messengers. Passed between, you could say, connecting the matter particles. 00:04:00.100 --> 00:04:02.799 Which they use to tell each other how to move. 00:04:02.800 --> 00:04:07.620 Each particle uses a certain set of the forces to interact with other particles. 00:04:07.620 --> 00:04:12.540 Quarks, for example, can interact with each other with electromagnetism and the strong nuclear force, 00:04:12.540 --> 00:04:16.680 but electrons don't use the strong force, just electromagnetism. 00:04:16.680 --> 00:04:21.880 The quarks exchange strong force bosons, communicating the strong nuclear attraction to each other, 00:04:21.880 --> 00:04:27.600 while the protons they build exchange the particles of electromagnetism, photons with the electrons. 00:04:27.600 --> 00:04:30.340 Thus, the quarks end up locked up in nuclei, 00:04:30.340 --> 00:04:35.990 while the electrons remain attached by their electric attraction, building atoms. 00:04:35.100 --> 00:04:40.680 Even though the universe has lots of big, messy phenomena like life, supernova, and computers, 00:04:40.680 --> 00:04:42.580 that seem complex on the surface. 00:04:42.580 --> 00:04:48.140 If you zoom in far enough on anything, you just get 17 particles emerging from underlying fields, 00:04:48.140 --> 00:04:50.300 playing a game with 4 rules. 00:04:50.300 --> 00:04:55.780 To summarize, in the most basic form we know right now, this is what things are. 00:04:55.780 --> 00:04:59.919 This theory is what physicists call the Standard Model of Particle Physics. 00:04:59.920 --> 00:05:02.320 You are basically nothing more than disturbances 00:05:02.320 --> 00:05:08.300 on an ocean that's excited by energy and guided by forces that make up the rules of the universe. 00:05:10.460 --> 00:05:12.940 But why? And what is a force? 00:05:12.940 --> 00:05:17.480 We'll have to explore a few more simple questions to get to the bottom of this. 00:05:17.480 --> 00:05:22.260 We made some wallpapers from some of the graphics in this video: You can get them on patreon.com 00:05:22.260 --> 00:05:25.500 If you want to help us make more videos, you can do so there. 00:05:25.500 --> 00:05:27.940 We really appreciate your support. 00:05:27.940 --> 00:05:31.700 While you decide, here are some more videos we made.