Name: Luciano
Status: student
Grade: other
Country: Italy
Date: Spring 2012
Question:
If my informations are correct the age of the Universe is about 13.700.000.000 years and the maximum distance of an observed event is 13.300.000.000 light years because this event occurred 400.000.000 years after the Big Bang (in other words it has occurred 13.300.000.000 to this light to reach us). So, as the maximum diameter of the Universe at that time was 800.000.000 light years and our bodies are made of atoms of matter that were in this ballĀ of such a diameter and that nothing can be faster than light, how is it possible that we see that light only 13.300.000.000 years later?
Replies:
Luciano,
Distances in the universe are not constant over time. Distances are not even constant from one observer to another. Consider things from the point of view of the star that sends the light. The receiver of the light is moving at almost the speed of light away from the sender. The light is sent. It spends over 13.000.000.000 years chasing this very fast receiver.
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