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Dating techniques for our universe 
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#1
Jan2606, 05:50 AM

P: 4

Can someone tell me why people age our universe at about 13.7 billion years? I know this is done with WMAP, but I can't seem to make much of that. Is there a measurement that aims to explain the age of our universe with just the help of our solar system?
I know there are some methods of trying to find out it's age, with the following: globular clusters, radioactive elements, and Cosmic microwave background radiation (CMB) which is done by the Wilkinson Microwave Anisotropy Probe (WMAP) and tempature measurements. The only star we can measure that is not light years away is our sun. The sun is supposed to be 4.5 billion years old measured through stellar evolution, and nucleocosmochronology. Do other techniques give us the same answer? Can we prove that any of these techniques are truly true? 


#2
Jan2606, 07:06 AM

Sci Advisor
P: 1,047

The age of the universe is basically determined by four parameters in the cosmological model under consideration: the energy density in the universe, the energy density of matter related to the critical density ([itex]\Omega_M[/itex]), the energy density of the cosmological constant related to the critical density ([itex]\Omega_{\Lambda}[/itex]) and the value of the Hubble parameter today ([itex]H_0[/itex]). These parameters together with the Friedmann equations allow you to determine the age. For the estimation of these parameters the main source of information is the angular power spectrum of the anisotropies in the cosmic microwave background. One takes this as an input to put constraints on the parameter space that determine the whole cosmological model. By the way, the usual parameter set is far larger than just these four parameters and this it is not possible to determine all four values unequivocally with the data (there is some degeneracy). However, there are other sources of information that can be used to determine some of these four parameters, for example, the [itex]\Omega_{\Lambda}[/itex] can be estimated from the luminosity curves of the supernovae 1a.



#3
Jan2606, 01:35 PM

Emeritus
Sci Advisor
PF Gold
P: 2,977

The Age of the Earth 


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