Showing posts with label Time. Show all posts
Showing posts with label Time. Show all posts

Saturday, November 12, 2016

Light, Life and Information

Seeing Clearly

Millions of living things in the animal and plant kingdoms have a working relationship with light.  Any with sentience "know" what that relationship is.  Or, at least, they make decisions based on perceptions of the benefits of that light.

Light is a form of energy as is evident in the growth of plants.  Without light, green plants die.  Even with plenty of nourishment and hydration, the healthiest of plants need light.  This energy is used to combine water, carbon dioxide and various other nutrients to build stems, limbs, leaves and fruit.  This energy is then released when that material is consumed by other organisms or by combustion.

But the most remarkable thing about light is that it allows sentient beings to gather information from the environment remotely.  Direct contact is not necessary when we animals can see things around us.  Some of us need help as our eyes, wonderful light receptors that they are, become weaker.

I know that light moves so fast that, comparatively speaking, things close by and far away are equally accessible.  However, there are ways to slow light down just a little.  When this happens, light is scattered, absorbed or reflected.  In this way, over time, scientists have figured out that light travels through a vacuum at about 186,282 miles per second.  That is fast enough to travel around the earth at the equator about 7.5 times!

Since light moves so fast, information from all over the universe is accessible on a clear night.  Certain stars, along with the moon, allow navigation along the surface of the earth because the information is predictable.  Based on the apparent movement of the sun on the horizon at sunrise and sunset, we are able to discern the passage of time.

So, what do I know?

  • Light is basically energy.
  • Light travels very fast.
  • Light enables access to information.


Monday, March 14, 2016

Thinking About Time

It's About Time

According to Albert Einstein, time is relative.  For the most part, there are two things that can change time: gravity and speed.  I will deal with these exceptions after I give a rundown on the obvious things I have learned about time.

First, the basic unit of time is the "second." Though the history of this unit is interesting, suffice it to say that its exact length was only settled in 1967.  It was then defined as a measurement "periods of radiation" of the caesium atom.  The old "second" was slowly changing since it was based on an average (actually a "mean") year.

A few years later, it was discovered that not only light was affected by gravity (as per Einstein's theory of Relativity), but so was time!  An atomic clock in Denver runs a bit faster than one at sea level (like in London).  Now only clocks at sea level are used to define the second.

Generally speaking, though, a second is 1/3600 part of a standard hour, of which there are 24 in a standard day.  That means there are 86,400 seconds in every day.  This is presently within two ten thousands of a second.  Close enough for me.  Given that each year is about 365.2425 days (rounded), the exact number of seconds per year varies, being corrected with "leap years" and "leap seconds" to keep things orderly.

I still remember playing with the numbers back before I reached a billion seconds -- about 31.7 years.  Now I am approaching two billion seconds!  In fact, by my calculations, I will turn 2 billion seconds old during the last week of May of this year at 63 years, 138 days +/- a day (leaving room for a miscounted leap day in there somewhere). Taking in account my conception being about 9 months before my birth, I have already exceeded the two billion mark!

A billion minutes ago, Justin "Martyr," a disciple of John the Apostle was preaching in the year AD 114.  Two billion minutes ago, in 1787 BC, Abraham lived with his grandsons Jacob and Esau when they were in their teens to mid twenties (allowing for differences in calendars).  What a difference of a factor of 60 can do!

It makes one consider just how big a billion is, but then, we are each made up of trillions of cells.  Numbers that big are dependent on what you are measuring.  It scares me that our national debt is measured in Trillions.. that is, a thousand billions!

But back to time... A million seconds passes really fast.  We each see our millionth second when we are ll.574 days old.  By the time your finished first grade, you had passed 200,000,000 seconds!  What a milestone! And you thought your daddy was old.  By 500 million seconds you were getting that driving license!  And then you just lost track of time.  Or maybe, you are in those years right now!  I forget who may be reading this blog.

So, to my young readers, count your days if you want, but leave the seconds to us old folks.  Time is, after all relative.  It passes a lot faster -- or seems to so, the older we get.  In my memory, things get crunched so as to seem like they were just last year, when they happened when I was half my present age.

Savor the days you have, and make lasting memories.  You don't want to forget the "good old days" as you age.  Even "bad memories" give you a perspective on life, so learn to get as much as you can out of them.

My goodness, I seem to have written quite a bit and said very little.  As the clock ticks away the seconds -- yes I have at least one clock in the house that ticks -- I will remember the days, some of the minutes, and an occasional second that made a difference.  But now, I think I will post this and go to bed.

So, What do I know?

Time is precious.  There are only 86,400 seconds and we sleep through about 30 thousand of them!  But then, we live to be over two billion seconds old!  At least on an average, we do.

Though time really is "relative," in everyday life each minute is the same for everyone in the world.  It comes, and it goes.  What we make of it is up to us.

Tomorrow, back to more practical things.