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Name: David M.
Status: educator
Age: 60s
Location: N/A
Country: N/A
Date: 2001-2002

I know that scientists believe that space is expanding. What causes it to expand? If some kind of energy is involved, where does this energy come from?

Hi, David !!

Well, at first, Einstein thought that the space was NOT expanding, and used in his calculations a factor, named COSMOLOGICAL CONSTANT - so that the expansion would be cancelled.

Later on he understood that the expansion of the universe really happens. His theory had showed him this fact !!! The shift of the light to the red confirms this expansion. The universe has a constant energy since the beginning. Mankind has lost Fred Hoyle, the scientist who created the expression "Big Bang" some weeks ago, at the age of 86. He was against the idea of the "Big Bang" to explain the origin of the universe. What really happens is a change of energy from a type to another. Mass is a concentrated form of energy. To explain the expansion of the universe, there is the theory of spontaneous generation of matter, what means, mass appears from energy to fill the space so as to contradict the "Big Bang" theory.

But, anyway, the energy of the universe is constant. It was already there at the beginning and is still there today. All that happens is a change in the form of energy. all the best !!!

Alcir Grohmann


Scientists do not really know why space is expanding. Measurements and observations are best explained by considering the universe to be expanding. There are a variety of possible explanations, although we do not know whether any are correct.

The most popular is the Big Bang Theory. It is possible that many billions of years ago the universe exploded like a super-giant hydrogen bomb. The atoms of the universe were formed from this excessive energy of the explosion. Small atoms merged together to form stars. Some atoms joined together into larger atoms, which became molecules and then planets. Everything was flying apart, and still is. Now, however, things are not flying apart as fast as when the explosion first occurred.

Some theories say the universe will continue to fly apart forever. Some say it will one millennium stop expanding and start contracting together again. No scientist knows for sure.

Dr. Ken Mellendorf
Illinois Central college

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