Is the Universe really infinite/absolute 0

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mcafej
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Ok, so I was just thinking about this today. First off, I was thinking about absolute zero, and how they say it's impossible, but then I thought about what the average temp. of the universe is. According to several internet sources, the current average temp is about 2.73 kelvin. I was wondering, how is that possible if the universe is infinite if the average temperature is above 0 (because you would end up getting all the temperatures over the area, which is infinite, so you would end with an average temp of 0)?
 
There is no evidence that the universe is infinite. The observable universe, which is the part that we can see and interact with, is clearly finite.
 
mcafej said:
Ok, so I was just thinking about this today. First off, I was thinking about absolute zero, and how they say it's impossible, but then I thought about what the average temp. of the universe is. According to several internet sources, the current average temp is about 2.73 kelvin. I was wondering, how is that possible if the universe is infinite if the average temperature is above 0 (because you would end up getting all the temperatures over the area, which is infinite, so you would end with an average temp of 0)?

There is zero evidence either way as to whether or not the universe is infinite or finite, but what difference does it make? Given homogeneity, why would you expect the average for one big volume (say the size of the observable universe) to be different than another big volume?