Are there Laws of Information?
Suppose I told you this..
"I weigh 175 lbs."
I just gave you some information. But what exactly is information, and can it be defined in a quantitive way to become a key concept in math and physics? Let's look more closely at what I just gave you..
It removed an uncertainty. Meaning, before you read the statement you were uncertain about my weight. Reading the statement removed your uncertainty. So perhaps information is simply the removal of uncertainty. Great, we've defined information!
Not so fast..
I gave you the information by publishing it in a blog. So you were not the only person to receive it, thousands of others did also. Perhaps some of those people were my family. But they already know this, so for them it did not remove an uncertainly. Which means for them it was not information!
So, our definition is true for some people but not for others. That's a bad definition. We need something better.
OK, let's forget this whole thing. I regret giving you the information, so I'll just delete it.
Not so easy. I can delete it from the blog, but thousands have read it and they remember it. I can't delete that. So perhaps we've discovered the first law of information..
"Once received, information can never be deleted."
Oh boy, information is getting complex. What kind of stuff is this?
It gets more interesting. The above statement implies there's some information that's never received. Can this be true? If it's never received, ever, then how do we know it exists? We don't. So perhaps we should restrict our definition of information to information that's received. Then our first law of information gets even simpler..
"Information can never be deleted."
Does this mean the information content of the universe is constantly increasing, for the simple reason that information cannot be deleted?
Let's look more closely at what happened when the above information was received. The person receiving the information scanned it and committed it to memory. So they can recall it anytime they want. We don't know exactly how memory works, but we do know that something must have changed in the brain's neural structure in order to store this information. And no change comes for free, a small amount of energy was required to process and store the information. So perhaps we have a second law of information..
"Receiving information expends energy."
This statement is interesting for two reasons. First, it shows there's a relationship between information and energy. Second, it indicates a possible quantitative definition of information.. perhaps we can relate the amount of information in a message to the amount of energy needed to receive the message.
Content written and posted by Ken Abbott firstname.lastname@example.org