Relativity - A Primer

Einstein's first paper on relativity came to some rather mind blowing conclusions:

1.  Time actually slows down the faster you are moving (what?)

2.  The speed of light (C) is always the same relative to you...without regard to your own speed (your just crazy now...)

The fact is that the only reason these conclusions are so mind blowing, is that we, as humans, are very limited in the ways in which we can "see" stuff.  The old saying is that seeing is believing...but we all know this is not true.  If a tree falls in the forest and no one is there to see it, it did indeed fall (as can be easily verified by visiting the site after the tree has fallen).  This is true in all realms of science.  Humans can only "hear" a small frequency range of sounds.  That means there are all kinds of sounds happening around us at any given time that we are oblivious to.  But there is a chance those same sounds might be driving your dog insane.  Our vision is even further constrained to visible light in the fact that we can't actually "see" most of the light in the universe (while other species and sensors we have built can).

The same can be said for relativity.  The only reason the above two concepts do not make any logical sense to us is that we, as humans, have no experiences traveling at super fast speeds, and we have no concept of living on, or around super (and I mean really really large) masses.  The Earth is big, but its a grain of sand compared to other objects in the Universe.  But if we did live truly in the fast lane, on a space ship flying at the speed of light, or if we lived on the surface of a super massive object (like a collapsed cold star)...these ideas would be as normal to us as apples falling to the ground or the colors of the rainbow.

Below is an excellent primer on the ideas of Einstein's theory of special relativity.  I promise when we are done, you will be able to easily understand what relativity is and how it works...just like Einstien...and you'll likely have even more admiration for the man for the creative capability to imagine these natural concepts which elude our every day lives...

So just why is this Einstein guy famous?

Everybody knows this guy. It doesn’t matter if you are a scientist, engineer, musician, athlete or an office worker. Albert Einstein is amazing simply for the single achievement of becoming the “rock star” of scientists. The only other scientist to ever come close to his level of world wide fame might be Sir Isaac Newton (whom we will introduce next post).

So why all the fame? Do you know just what it was that made this guy so great? Sure he’s smart, but there are tons of smart scientists out there that are virtually unknown (in fact most of them are pretty obscure).

Here’s one reason:

E=mc²

One of the most simple and elegant science equations ever written. Only 3 letters (variables) and one is usually always constant (c). But why? What does this equation mean? Just why is it so important?

First off, since this blog is written for those with no science and math background, lets make sure we understand just how simple and easy a math equation is to understand. I know, most math equations look like greek to most people, but they are actually very easy to comprehend by anyone, way more easy than learning another language (the author is currently learning French).

So, lets start off by translating this equation into English. After all, every math equation is just another form of a “sentence” expressed in the language of algebra.

What this equation says in English is simple: All the energy (E) in an object has to be equal to the amount of mass (m) in the object multiplied by speed of light (c) squared.

(Notice how math reduced all that text down to three letters with no loss of meaning. This is one reason why math is considered the "universal language")

A “square” is a simple concept you learned way back in grade school. It’s a number multiplied by itself. So the square of 8 is simply 8 times 8, which equals 64. Here’s the deal, the bigger the number you are squaring, the bigger the total square is going to be. In this case, “C” is the speed of light, which is an amazingly big number: 671 million miles per hour to be exact. Think about that for a minute, how fast does your car go? This can only mean that when we square this number by multiplying it by itself, we are going to be left with one insanely huge number: 450,241 TRILLION. That’s a hell of a number. One that the human mind, even Einstein's, cannot truly comprehend.

So the basic idea here is that “c²” is big…really, really, really big. Now what happens when you multiply this huge amount with any other number (in this case, an object's mass)? Even if the number is very very small you will still be left with a huge number in the end.

So what this equation is saying is that there is a hell of a lot of energy stored in even the smallest amount of matter. So much energy in fact, that if you could release it, you’d end up with this:

That’s right, nuclear fission is the process of splitting apart a very small amount of matter (just a couple of atoms). Most of that matter is released in the form of “radiation”, which for our purposes is the same thing as energy. Light, heat, gamma rays, x-rays…etc are all forms of radiation or energy. We see the light and feel the heat from the explosion; we don’t see the huge amount of energy that is released as harmful radiation. But its in there.

This is what Einstein is partly famous for (we’ll get into some other cool things later).

But the basic understanding here, that everyone can easily understand, is that Einstein discovered a basic law of nature. A law that states that every little bit of matter that exists in the universe is actually an extremely dense form of tightly packed energy. A similar (but not entirely accurate) way to think of this is: matter is like energy that has been “frozen” down to a really small space.

Now, the next time you see a picture of Einstein, watch a video of a nuclear explosion or see the most famous equation in the history of science, you'll know exactly how they are all related and exactly what they mean. In fact, you now have the same understanding as a scientist...just with out a lot of the math that was used to prove it!

A sort of introduction.

Ask yourself a question: do you understand what the above two equations "mean"? I suspect for most, the truthful answer is no, which is a really good illustration of how we tend to fail at conveying science.

Recently, I read a story on digg and reddit that asked the following question: are you wealthier today than John D. Rockefeller (whom was worth close to 80 billion dollars in the late 1800's)?The truth is that, in almost every meaningful and measurable way...you are. The reason is not money, but time and the above two equations. You were lucky enough to born a little over 100 years later after engineers had some time to tinker with these equations...the benefits of which Rockefeller, despite all his wealth, could never enjoy.

Lately, "climate gate" has been a leading headline in the news. The following discussions that occurred made it clear that scientists have a problem. They have a very big problem: no one else can figure out what the hell they are doing, why they are doing it and why it matters.

Scientists are great at a lot of things. They are smart as hell. But one weakness just about every honest scientist confesses to in secret is that they are bad communicators. One needs only to sit in any University Freshman Physics or Calculus course to see this illustrated first hand.

That's why this blog exists. Being able to do the whole "math" thing makes life a bit easier I find. Bear in mind I don't consider myself to be "good" at math, and I certainly don't like it. Yet I have always found it somewhat easy to do and very useful. I tend to live in the layman's world, only temporarily hopping over to the ivory tower to check out whats going on. In this blog, my goal is to help you understand a little bit more about what these weird guys in lab coats are up to all day. When it matters, when it doesn't, and to delicately mock the journalism profession for endlessing screwing up their job in this respect.