Scientific American

Problems(3) The universe.

A. Knowledge

Today it is even possible to doubt the basic assumptions of science.

1. There is an objective reality even if there is no observer.

a. We learned that reality changes when it is observed. See the two slits experiment when particles are passed through them.

b. It is accepted by scientists that we live in a hologram, and what we see is not really there.

2. We can learn something about the processes that exist in this objective reality.

Much of what we thought that we knew in the past is now seem to be mistaken. Which knowledge that we have today will be seen in the future to be mistaken ?

3. Sometimes the known "laws of nature" are correct only in certain circumstances - Newton's laws are correct as long as we are not traveling fast.

4. It is not easy to relate to different ideas about the universe.

The rule of falsifiability can help in choosing which ideas to accept.

B. The multiverse

Empty space is not empty. There are many particles that suddenly appear and suddenly disappear It is thought that they come from and go to different universes.

It is suggested that some galaxies are drawn aside because of the gravitation pull of a nearby universe.

There are two kinds of universes. There are those that begin from the eruption of black holes, and those that come into being because of the laws of quantum mechanics which maintains that every time that any event occurs all the possible outcomes create alternative universes that are similar to our own. The people in these universes all feel that their universe is the "real" one.

C. Our universe

1. It was commonly thought that time started with the birth of our universe. Now we have at least two ideas of how our universe came to be. Either it was the result of the explosion of a black hole or that two large dimensions collided. It seems to me that the first idea is preferred by the scientists.

2. There are two possibilities for the death of the universe. Either all the energy will deteriorate as predicted by the law of entropy, or the universe will expand so that the galaxies will be too far apart to see each other. In bothe cases it will be a cold death.

3. Today we can see the boundary of our universe. It has existed for 13.7 billion years and we can see what exists 13.7 light years away.

4. It is clear that the universe is not flat. It is either convex, or concave or saddle shaped. If we traveled in a "straight" line we might end up in the place where we started.

5, We have discovered all kinds of heavenly bodies like Quasers and pulsars and black holes. We will possibly discover more.

6. There is a high probablity that life exists on other planets. Attempts are being made to receive signals from advanced civilizations.