Calculating Temperature of Radiation at t1

AI Thread Summary
The discussion centers on calculating the temperature of radiation at a specified time, t1, given a hypothetical background radiation temperature of 1.95K. There is confusion regarding the relevance of t1 and whether it refers to a specific moment after the Big Bang. The Cosmic Microwave Background (CMB) temperature is mentioned, with the implication that a lower temperature would suggest an older universe. The original poster clarifies that the 1.95K figure was arbitrary, intended solely for exploring measurement methods. Overall, the conversation highlights the complexities of measuring and interpreting cosmic radiation temperatures.
NebulaBilly
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If there was background radiation of say 1.95K what would be the correct way to calculate the temperature of radiation at t1? Do we need to know what t1 is and also i have looked at Stefan Boltzmann law but i do not think that formula would be appropriate for what is trying to be achieved here.
 
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NebulaBilly said:
If there was background radiation of say 1.95K what would be the correct way to calculate the temperature of radiation at t1? Do we need to know what t1 is and also i have looked at Stefan Boltzmann law but i do not think that formula would be appropriate for what is trying to be achieved here.
What is the significance of ANY characteristic at "t1" (assuming you mean one second after the singularity) ?

Are you talking about the CMB? If that were 1.95K then the universe would be MUCH younger than it is currently measured to be with a CMB of about 2.7 degrees.

OH. Wait. You're saying 1.95Kelvin. I stupidly read that as 1.95 thousand. Never mind :smile:

If the CMB were 1.95K instead of 2.7K then that would imply that the universe is older than we now think it is.
 
phinds said:
If the CMB were 1.95K instead of 2.7K then that would imply that the universe is older than we now think it is.

I just used a made up figure, just to ask the question how i would measure the temperature of radiation if i have a background radiaiton on 1.9K, its not a figure i have got anywhere i just used it for the purpose of the question
 
NebulaBilly said:
I just used a made up figure, just to ask the question how i would measure the temperature of radiation if i have a background radiaiton on 1.9K, its not a figure i have got anywhere i just used it for the purpose of the question
You seem to be mixing apples and oranges here. First you ask how to calculate the temperature at t1 and now you are asking how to measure the temperature now. I'm not clear on WHAT you are asking.
 

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