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exploring: dark energy > why do we care

Dark energy must be different from anything we've yet seen.

Dark energy has captured the imagination of scientists because it must be very different from anything we know. In order to understand it, we would have to have a much better understanding of how space, time, and matter are related. This is the kind of challenge that drives revolutions in science.

There are subtle questions as well. What is the purpose of dark energy? What role does it play in the unfolding universe?   Such questions may seem unscientific, yet scientists continue to be astonished at the connections and relatedness within the physical world – a kind of "ecology of the universe." It would be surprising indeed if dark energy were an afterthought on nature's part.  

One of the most perplexing questions is why the universe we observe today should contain an amount of dark energy comparable to the amount of normal matter. Why not much more or much less? What is special about this near-balance between dark energy and normal matter? No one knows yet.

It seems curious that dark energy should be discovered at just that time in history when we thought we had finally answered the ancient Greek question, "what is the world made of?" It took two thousand years to answer that question. First, we had to invent science along the way. Finally, we have studied and understood all of the chemical elements and many of the fundamental particles of which they are made. We have periodic tables and textbooks crammed with lists fundamental particles. Yet now we find that most of the universe is made of something completely unknown. It is as though we are now the ancients, asking questions of nature that we do not yet know how to answer.

This great dialogue with nature seems to keep going. Where it is going no one really knows yet; the next generations will have a better idea. But what a marvelous journey!



Where did the idea come from?
What might Dark Energy be?
Why do we care? -

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