# What is the formula utilized to calculate the age of the Universe?

I have heard from different scientific sources stating different ages for the Universe such as 13.7 billion or 14.7 billion. I would like to know which is correct and how the number is derived.

Relevance
• Anonymous

Technical explanation:

The problem of determining the age of the universe is closely tied to the problem of determining the values of the cosmological parameters. Today this is largely carried out in the context of the ΛCDM model, where the Universe is assumed to contain normal (baryonic) matter, cold dark matter, radiation (including both photons and neutrinos), and a cosmological constant. The fractional contribution of each to the current energy density of the Universe is given by the density parameters Ωm, Ωr, and ΩΛ. The full ΛCDM model is described by a number of other parameters, but for the purpose of computing its age these three, along with the Hubble parameter H0 are the most important.

Non-technical explanation:

Age and distance in light years correlate in that something known to be 12 billion light years away means that light from that something has been traveling for 12 billion years, so we know the universe must be at least as old as that. The Hubble Space Telescope has imaged galaxies and quasars out to that distance. The distance ladder gets shakier and shakier as you go further out. The distance to nearby stars is measured by parallax. The distance to nearby galaxies is measured by certain types of stars in them whose absolute magnitude is known. The The part that's hard to pin down is if the universe has been expanding at the same rate over billions of years. 13.7 billion to 14.7 billion years old is a good current estimate.

NASA's Wilkinson Microwave Anisotropy Probe (WMAP) project estimates the age of the universe to be:

(13.7 ± 0.2) × 10^9 years.

That is, the universe is about 13.7 billion years old,with an uncertainty of 200 million years. However, this age is based on the assumption that the project's underlying model is correct; other methods of estimating the age of the universe could give different ages.

This measurement is made by using the location of the first acoustic peak in the microwave background power spectrum to determine the size of the decoupling surface (size of universe at the time of recombination). The light travel time to this surface (depending on the geometry used) yields a pretty good age for the universe. Assuming the validity of the models used to determine this age, the residual accuracy yields a margin of error near one percent.

This is the value currently most quoted by astronomers.

• Anonymous
4 years ago

No I don't... but just as others should not have a say in how I raise my kids, I should not have a say in how others raise their kids. I am against indoctrination but I can't see how to fight it without taking away the freedoms of others. I mean what if someone told you it was wrong to let your kids play with Ninja turtles action figures because it advocates vigilantism? So while my personal opinion is that teachings in the bible directed towards young children that glorify the violence and genocide within the bible using action figures are indeed wrong.. I cannot forget that other people may think the same about many other action figures and the ideals they represent. Once you start there it won't stop at that, pretty soon any violent action figures will be banned.. For example I think Bratz dolls teach girls to be self-centered and shallow, but is it my place to tell people they can't buy them for their children? No it's not. I wouldn't want someone else telling me what my kids can play with that is acceptable, so I won't do it to other people.