The famous equation E equals MC squared tells us that the energy of a particle is proportional to its mass So if you wish to create mass we could imagine having its energy would allow for this But it turns out that twice the energy is needed But what I want to get into we need a short detail here into per production and annihilation That's because we need to produce not only a particle, but its anti-particle Electrons have an anti-matter particle called the positron almost identical to each other But with an opposite charge what this means is that the act oppositely in electric and magnetic fields Shown is a cloud chamber the inside is saturated with water vapor and if a charge particle moves through it It will leave a track behind her as water droplets form What the scientists did was applying magnetic field so moving charge particle would once move in a circle The size of which is related to their mass the purpose of this is that different charges move in different orientations around a circle For example a positive charge might go clockwise whereas a negative charge will go anti-clockwise What code the Anderson found was a positive charge in cosmic rates not unusual as both protons and alpha particles are positively charged However, he found the mass of the particle to be significantly less than that of a proton. It was at most twice the mass of an electron This bigger from 1932 winning the Nobel Prize for Physics in 1936 shows the positron as the long line through the middle Today with better detectives as well as the ability to create per production on demand We have much better figures demonstrating per production For example this one was taken from the aliph detector at CERN showing per production of electron positrons The reaction that causes an electron positron per is a photon splitting into an electron and an anti-electron The energy the photon has to be enough to create both of the particles now into the meter the video What the equation E equals MC squared does is relate mass to energy that is if we had some mass and if it was all changed to energy This is how much energy we should get For example if you could turn a kilogram of mass about one meter of water into pure energy how much energy would you get? The speed of light is exactly 299 million 792,458 meters a second So the square of the speed of light is about 9 followed by 16 zeros As we had one kilogram that means we get 9 followed by 16 zeros joules of energy These numbers are kind of meaningless without an example So let's consider fat man the bomb that was dropped on Nagasaki It had about 9 trillion joules about 9 followed by 12 zeros So we need 10,000 of them to match one liter bottle of water However to change your liter of water to energy you will need a liter of anti water which is rather hard to find So you may be wondering what's the point of the equation the equals MC squared? How could we possibly use this concept? To do so I'm going to have to make a few things clear Because of the equation we can talk about mass in terms of energy or energy in terms of mass However when we have a very very small amount of energy we need a better unit than a joule To do this we're going to have to define a new measure of energy So we define an electron volt to be the energy an electron gets when it is accelerated through one volt of potential difference This is a very useful unit as it's about the energy scale of the mass of particles a mega electron volt is a million electron volts So let's now look at the mass of some particles the mass of an electron is 0.51 mega electron volts the mass of a proton 938.3 mega electron volts A Neutron has mass 939.6 mega electron volts and the deuterium nucleus has a mass of 1,875.8 mega electron volts Now a deuterium is made up of a proton and a neutron that have been bound together So if we add the mass of a proton to the mass of a neutron We find that the total mass is 1,877.9 mega electron volts However, the mass of a deuterium like I just said is 1,875.8 Why is deuterium lighter? 2.1 mega electron volts is quite a substantial amount like I said an electron has mass 0.5.1 mega electron volts The reason deuterium is lighter than the sum of its parts is that when a neutron and proton bind together to form a deuterium It loses some mass But what do I mean by a loss of mass? Remember that mass and energy are equivalent So what I'm actually saying is a loss of energy and so we introduce the concept of binding energy That the bound system can have a different energy than the sum of its component parts due to the interaction of the parts For example, if you push together two of the same poles on a magnet or if you push together opposite poles the energy is different If a system had a state of lower energy once in that state Energy would need to be added in order to put it back into its original state But as the system goes into a lower state by conservation of energy the difference of energy has to come from somewhere So the mass decreases in order to compensate again by equals mc squared In order to separate the system back to its component parts the same amount of energy will need to be put back into the system This process is the basis of how nuclear fusion and vision both work Fusion is when we push together atoms protons and neutrons for example Borming a new atom like we have just shown a proton and a neutron binding together to form a deuterium We could also fuse to deuterium nuclear atom to form a helium nuclear Each releasing energy when the particles get fused However as we fuse more and more particles together the amount of energy released decreases However the binding energy is still increasing up to a point once past this point the binding energy decreases Once the binding energy for lighter elements becomes higher than that for having if we separate the heavy elements We get energy released as the system is now going to a state of higher binding energy This is the process of nuclear fission Note that both of these processes can happen at any binding energy except you only get energy released when you go into a higher Binding energy for an example of a fission reaction uranium 238 visions into an alpha particle and thorium 234 By a similar concept if we look back at the mass difference between a proton and a neutron a neutron has more energy than a proton it has a higher mass So neutrons are able to decay into a proton This is via the reaction of a neutron changing into a proton an electron and an anti-electron neutrino This is a process of a decay of a free neutron That is when the neutron isn't caught up in an atom Neutrons have a half-life of about 15 minutes that is given a very large number of neutrons after 15 minutes you expect half of them to be gone If you have a single neutron after 15 minutes, there is a 50% chance for it to have changed into a proton More accurately the wave function of the neutron has changed into a superposition of both each with probability of half That's it for part one in part two we will show how this explains nuclear synthesis