Eventually, I’ll try to add graphics to this article to aid in understanding. I'll also give it better formatting.
The first thing we need to do is stretch your mind beyond the neighborhood you typically survive in. The objective here is to delve into time, energy and matter. For now you can forget about the timing of the alarm clock setting on the stand beside your bed. Let’s start with another aspect of physics that you see in every day life but can be confusing. In physics or nature we have many related things that we give little thought to. An example is electricity and magnetism. We normally see them as two different entities. Actually they are the same entity. Near your house is a transformer that converts high voltage to 115 VAC so you can use it in your house. You will see the transformer on a telephone post or it will be in the rear of your yard or a neighbor’s yard. The transformer has 2 sets of wire windings spiraled around a metal core. One set is called the primary and the other set is called the secondary. These two coils of wire are not physically connected to each other by an electrical conductor. The high voltage travels through the primary wire windings of the transformer and the electricity is converted to magnetism. The iron core of the transformer is used to help improve the magnetic strength. The other secondary set of wire windings will capture the magnetism and change it back to electricity. The number of windings in each set of wire coils will determine if the voltage increases or decreases. You don’t get something for nothing here. If the voltage is increased then the available current will decrease. The overall power is a product of voltage times the current and the power remains the same less the loss of power in the transformer. You might notice that snow melts off the transformer before it melts off other things because of the heat created by the loss of energy in the transformer. Don’t ever touch the transformer to feel the heat. If you touch the secondary you will be blown into the middle of next week. If you touch the primary you will blown into the beginning of your next life assuming you get one.
A motor is another example of electricity and magnetism. In this case the electricity is turned into magnetism and the magnetism pulls on ferrous metal in the motor and makes it turn. A motor and a generator are almost the same. With the generator we apply force to it and it creates electricity. There is already a small amount of magnetism in the generator to start the production of electricity but the generator also uses a small portion of its own energy to increase the strength of the magnetism so the electricity can be created. To simplify these phenomena we can say that any time a wire passes through a magnetic field, a voltage will be created in the wire. Anytime electricity passes through a wire it will create magnetism. To pass electricity through a transformer the electricity must be changing voltage. It is the change in voltage that causes a change in magnetism and the movement of this magnetism will create electricity in any other conductor it passes through.
Now we will talk about other things in nature that have symbiotic relationships. Symbiotic may not be the best word but it seems that way. Light is another thing we will deal with. It travels at high speeds like electricity but light is constant and electricity has slower variations.
The speed of light or electricity is a very difficult thing for the human brain to comprehend. This is because of the speed light travels. We think in terms of flying around the Earth in a few days with our high speed aircraft. We can travel around the Earth in two hours in an orbiting spacecraft. It takes light about 1/10 of a second to travel around the Earth, assuming it could travel in a circle. In fact in 1 second light will travel around the Earth 7.75 times. Now try to imagine how far light will travel in one year. Now, to stretch your mind it should be understood that some of the galaxies we can see from Earth are billions of light years from us. So while the light from the moon gets to us in 1.3 seconds it takes light 4.5 years to get to us from our nearest star and a billion years for it to arrive from another galaxy.
It is like BC in the comic strips. He puts a bottle in the ocean with a message. The message says “Oh great guru, what is the meaning of life.” Assuming there is life on our nearest star and if they respond immediately it would be 9 years to receive a response. Nine years later a message might come back that says the answer is 42.6573. Now we respond by saying, “we have received the answer of 42.6573 but would you please remind us what the original question was?
So in order to understand E=MC2 we must understand the difference between 1 billionth of a second and 1 billion years. We must understand the difference between big numbers and small numbers even though our daily life consists of small numbers.
In the equation E=MC2 the only constant in that equation is the speed of light. Also keep in mind that we are not considering light in the equation but we are only using the speed of light as a mathematical reference. Just from a mathematical perspective we can now see that E (energy) and M (matter) are not constants. They are directly related to each other. They are one and the same. Energy can become matter and matter can become energy. The Big Bang theory enters into this relationship with matter and energy and it justifies the theory that the entire universe, at one point in time, did exist in the space of one circle with a diameter of less than one inch. That is a lot of energy in one location. There are more stars in the universe than there are grains of sand on the Earth.
First we need some astronomical distances. What is the distance from the Earth to the Sun. Do you have any idea how this is calculated? When contemplating various solutions remember we did not know exactly how much the Earth weighs or just how much gravity the Sun is imposing on us. So centrifugal force and time around the Sun cannot be used for calculations.
Keep in mind that if you know the distance between any two planets in our solar system you can calculate the remaining distances. This is also true if you could figure out the distance from any one planet to the Sun.
The first fairly accurate attempt was using a parallax to Mars from two different locations on Earth. The angle between Mars and a nearby star are taken at the exact same time from two far different points on Earth. The shift in angle from the two observer positions can be used for calculation to determine how far Mars is from us.
Now if you know how far Jupiter is from the Sun we have an extra value tool we can use. The first quantitative estimate of the speed of light was made in 1676 by Ole Rømer, who was studying the motions of Jupiter's moon, Io, with a telescope. It is possible to time the orbital revolution of Io because it enters and exits Jupiter's shadow at regular intervals. Rømer observed that Lo revolved around Jupiter once every 42.5 hours when Earth was closest to Jupiter He also observed that, as Earth and Jupiter moved apart Io's exit from the shadow would begin progressively later than predicted. When Jupiter was furthest from us the delay of the moon was about 18 minutes. This 18 minutes was regained as Jupiter came close to Earth again. Do your math now. Compute 18 minutes and the known distance of Jupiter from the Sun and you have the speed of light. Now with the speed of light you can divide 18 minutes by 2 and you have the Earth 9 minutes from Sun. This is a good way to check our previous calculations of how far the Earth is from the Sun.
Another way of measuring the speed of light is called the Aberration of Light. At the instant of observation of a star, the apparent position of the star is displaced from its true position by an amount which depends upon the speed the Earth is moving towards it or away from it. In the case of an observer on Earth, the direction of its velocity varies during the year as Earth revolves around the Sun, and this in turn causes the apparent position of the star to vary. This particular effect is known as annual aberration or stellar aberration, because it causes the apparent position of a star to vary periodically over the course of a year. This aberration can be measured and used to determine the speed of light.
Eventually we were able to bounce a radar signal off Mars and back to Earth. This confirmed the distance from Venus to Earth at a time when Venus was at a right angle with respect to the Earth and the Sun. With one distance known and 2 angles we can calculate for the remainder using simple trigonometry.
During World War II, the development of the Cavity Resonance Wavemeter for use in radar, together with precision timing methods, opened the way to laboratory-based measurements of the speed of light. I'll let you look up cavity resonance wavemeter if you must know how it works. It is extremely accurate and is today's reference for the speed of light and our known distances to other planets.
Here are some interesting facts to consider as you read on.
¨ Physics looks the same in all frames of reference. The remarkable discovery here is that an ordinary piece of matter such as a rock and a pencil appears quite different but both are actually manifestations of the same underlying phenomena.
¨ Mass can be converted to energy and energy can be converted to mass.
¨ We can further define E = MC2 by saying E = MC2 plus the energy of motion within the particle itself.
¨ When you turn on a flashlight and it emits light it actually loses weight.
¨ Space and time are two sides of the same coin. (Just like magnetism and electricity are one).
¨ Energy shows up in mass, heat, light, radiation. They are all facets of the same idea of energy.
¨ C or the speed of light is the limiting velocity of any motion.
¨ E = MC2 applies to what is going on in the sun.
¨ Moving clocks run slower. Moving meter sticks are shortened.
¨ Whenever you convert a piece of matter to pure energy, the resulting energy is by definition moving at the speed of light. Pure energy is electromagnetic radiation.
¨ Radiocarbon dating, which archeologists use to date ancient material is a measure of decay in mass seen in the formula E = mc2.
¨ The mushroom cloud of an atomic bomb explosion is E = mc2 made visible.
¨ The laws of physics are the same in all inertial frames.
¨ The speed of light is a constant in all inertial frames.
¨ Gravity and acceleration are equivalent, two facets of the same phenomenon.
¨ Space and time, matter and energy are, as Einstein proves, locked together.
¨ If objects gain mass as they accelerate then they would require greater push to go even faster. If an object reached the speed of light, it would have an infinite amount of mass and need an infinite amount of push. An infinite amount of push is theoretically impossible so matter cannot reach the speed of light and still remain matter.
As an object goes faster and faster its affective mass will increase. While this is true if it could reach the speed of light it would probably become pure energy. Another variation of this is that as you compress matter or increase the gravity that compressing it. It eventually is no longer matter and becomes pure energy. This tends to explain how the entire universe can be compressed into a sphere 1 inch in diameter and then explode to initiate the Big Bang theory. This can be proven scientifically but who knows what happened 1 second before the Big Bang. We are still learning.
According to Isaac Newton energy is accumulative. As an example lets say you are traveling on a train at 60 mph and I throw a ball at 40 mph in the direction of travel. The ball is seen to be going 100 mph as viewed by an observer on the ground nearby. The theory of accumulative energy stood for a long time. But remember that the speed of light is constant. Do we have a conflict with physics here? Let’s see what Einstein has to say about it.
Albert Einstein was well educated in math. He also was very intelligent. Then he worked in a patent office where his brain was constantly exercised with many new ideas. Einstein was already aware of Newton’s theory where energy was accumulative. He also knew that the speed of light was constant. You really do not need to be a genius to realize we have a conflict here. How can light be a constant if energy is accumulative. As an example, if I am traveling on a spacecraft at ½ the speed of light and shine a flashlight out the front window in the direction of travel, the light should be going 1 ½ times the speed of light. No! It is still traveling at the speed of light. The speed of light is CONSTANT in outer space. This discrepancy between the constancy of the speed of light and Newton’s addition of energy was conflicting and there had to be another variable. What is the variable? It was Einstein who first realized the variable is TIME. Einstein began by noting the Newtonian theory where velocities can be added and subtracted and the Maxwellian theory where the speed of light was constant are in total contradiction.
Actually the initial thought that pointed Einstein in the right direction was when returning home from his friend Michele Besso after an exhausting effort to understand the contradiction in physics of Newton and Maxell. He was riding in a streetcar in Bern and looking back at the famous clock tower that dominated the city. He then imagined what would happen if his streetcar raced away from the clock tower at the speed of light. He quickly realized that the clock would appear stopped, since light could not catch up to the streetcar, but his own clock in the streetcar would beat normally. So what is the variable here? TIME! The constant is the speed of light.
Our daily life exists in small numbers and the variation in time is immeasurable. But time is variable when delving into the world of physics and astronomy. Einstein first discovered the relationship between time and space. He then made the relationship between energy and matter. Einstein’s discovery opened up a whole new world of physics and discoveries.
On a Nova program on PBS they have a show explaining E=MC2. They use a moving train to make their presentation. I think they fail to properly emphasize that this train is moving at half the speed of light. We tend to visualize a train as a slower moving object. We must remember that the train is moving trough space at one half the speeds of light. In reality we could not watch the train do that unless it was a billion times further away from us and a billion times larger so we could still see it. As an example here, have you ever seen a very large cargo plain from a distance? We could even use the Boeing 747 as an example. From a distance it seems to be moving slowly across the sky. It really is moving very fast but because of its large size it appears to be moving slowly. We would need to create these same phenomena in order to visualize the affect on the visualization of any object traveling at half the speed of light.
So instead of using a train let’s use a very large Star Ship Enterprise space ship. It is moving past our Earth at 95% the speed of light. A person in the space ship is shining a very strong flashlight out the front window of the spacecraft and in the direction of travel. The people on Earth observe this as the spacecraft passes by. When the spacecraft comes back to Earth the people on Earth tell the astronauts that they were certainly traveling fast and they were going almost as fast as the light exiting the front of their spacecraft. In fact the light was only exceeding your speed by 5%. The astronauts would then say, “Oh no, the light was exiting our spacecraft at 100% the speed of light. Both the people on Earth and in the spacecraft are right. The variable here is time. Time was going 20 times slower for the people on the spacecraft than it was for people watching from Earth. With time going 20 times slower it made the light appear to go 20 times faster when it was actually only going 5% faster. Once again, the speed of light is constant and time is variable. My mathematical references here are used as an example. The relationship between speed and time are not linear in reality.
The equation E = mc2 was developed about 2 years after Einstein first came up with his theory of relativity. His initial equations are not something most people would understand. It would not be practical to publish here. But eventually he managed to simplify one equation we could all look at and possibly grasp. Let’s look at this equation closer. “C” is the speed of light. C2 is the speed of light multiplied times itself. If the speed of light is 186,000 miles per second then we are talking about 186,000 x 186,000 or 34596000000 in units of miles per second or 448,900,000,000,000,000 in units of mph. Actually Einstein was probably dealing with numbers in the metric system. You can do the conversion.
Now in the equation E = MC2 the C2 is on the right side of the equation next to M (matter). Mathematically, this means there must be an enormous amount of “E” (energy) in matter to equal MC2. In fact there is. One metal paper clip holds the energy of an atomic bomb assuming we had the ability to release that energy. Thank goodness we do not. E = MC2 provides the key to understanding microscopic radioactivity to the big bang itself.
According to Einstein's special theory of relativity, objects gain mass as they accelerate to greater and greater speeds. Now, to get an object to move faster, you need to give it some sort of push. An object that has more mass needs a bigger push than an object with less mass. If an object reached the speed of light, it would have an infinite amount of mass and need an infinite amount of push, or acceleration, to keep it moving. No rocket engine, no matter how powerful, could do this. In fact, as far as we know, nothing can exceed the speed of light.