Charles Keefer's Blog

So refreshing …

with one comment

To go on a cruise, that is.

There is a limited amount of the daily diary you can get on a cruise, mostly because you don’t want to consume it. So you can spend some time reading something serious for a change.

I just got off a four-day cruise and I read two physicists.

One was Victor J. Stenger and the other was Stephen Hawking.

Stenger, who was writing a book about how to be a better athiest, informed me that there really was no big bang. Hawking invented it about 1970 but then kept on working and and decided that, since he didn’t do it in quantum mechanics, there really wasn’t a big bang at all.

That was in Hawking’s History of Time, which I read, but I didn’t see that. It is good when people point out things you did not see.

Hawking, in his book The Grand Design clarified something that has mystified me since high school.

How can something be a particle and a wave at the same time – namely light.

Light acts like a particle in that it bounces off stuff and comes to our eyes, or a TV camera, and creates an image. Particles of light hit your eye, or a TV camera, and activate a pixel at a time. It acts like a particle.

But then there is the double slit experiment. Put a single frequency light – like a sodium lamp – at one end of a room and a sheet in front of a wall at the other end. Cut two slits in the sheet and stand behind it looking at the wall. You will see bars of light on the wall. It appears that light from the two slits is acting like waves, canceling out each other in the dark spaces and reinforcing each other in the light ones.

How can this be?

Hawking says that it is not a contradiction. It just is.

That is what my high school physics guy said, but I didn’t get it.

How can light be both a particle and a wave?

Here is what Hawking says.

You have to understand the world in terms of models. Scientists use observations and measurements to make a model. If the model faithfully recreates what something does and can be used to predict what it will do in the future, then it is a valid model. If it is off a bit, well that is what science is for – to fix it.

If light acts like a particle and at other times acts like a wave and both models accurately predict what it will do, then both models are correct. Since we don’t have a Theory of Everything, then we have to accept what our models show us.

Light acts as both a particle and a wave. Because we don’t have a model that explains why that is doesn’t mean that our two models are wrong. It just means we haven’t got a Theory of Everything that explains it.

Hawking says we have to look at what is in terms of our models. Newton’s laws explain most of the stuff we see. Quantum laws explain things we can’t see because they are too small. But we don’t use quantum physics to fly airplanes because Newton’s Laws work better in our world. And we don’t use Newton’s laws inside a nuclear reactor because they don’t work at all.

Both models work so that is how the world is.

What Stenger says is that just because we can’t explain the difference doesn’t mean that God did it.

Stenger has a theory that the universe as we know it has pretty much always existed because it is linked to another universe via a worm hole and stuff kinda goes back and forth between the two to keep things running. He says the math works.

I haven’t finished Hawking’s book. I finished Hemingway’s For Whom The Bell Tolls instead. It is supposed to be his best. I also read Hiaasen’s Native Tongue.

From all this I can tell you that it is better to contemplate the universe with humor than it is to take a lover for three days then die.

Advertisements

Written by Charles Keefer

March 25, 2011 at 10:27 pm

Posted in Blog, Books

One Response

Subscribe to comments with RSS.

  1. hmm, the things we would ‘know for SURE’ if we could access more than the small percentage of our brains that we do

    bev

    March 27, 2011 at 7:18 am


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: