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Q & A: The expansion rate of the universe is increasing

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Most recent answer: 12/08/2013
Q:
To my understanding, the light we observe from distant galaxies, it's light that was produced in the past. If this is the case thee wouldn't it be logical to say that the universe was expanding more in the past than it is now, since the expansion is greater the father we observe?
- Christopher (age 33)
Calgary, AB,CA
A:

Dear Christopher,

You have an interesting premise but experimental facts show that the opposite is true. The expansion rate is speeding up.   In 2011 the Nobel prize in Physics was awarded to astrophysicists at Berkeley who showed that indeed the rate of expansion of the universe is actually increasing.  This is attributed to some mysterious feature of the universe that is called "Dark Energy",  which makes up almost 70% of the energy of the universe.  The idea, although weird, is consistent wih Einstein's equations of general relativity   Ordinary matter, like what the stars as well as you and I are made of, makes up only 5%.    Take a look at: 

LeeH


(published on 12/08/2013)

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