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Ranku
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What is the easiest way to calculate dark energy and matter density at any given age of the universe?
Age of the universe.Orodruin said:Given what input data?
That is clearly not sufficient.Ranku said:Age of the universe.
Hmm...I am trying to calculate how the density of dark energy and matter varies over the age of the universe.Orodruin said:That is clearly not sufficient.
Then, in addition to age of the universe, either dark energy or matter density, or redshift.Orodruin said:So I ask again what input data you want to use.
So using the Friedmann equation.Orodruin said:You can easily compute how matter or dark energy density scales with the scale factor (and therefore with redshift). In order to know the actual density and how redshift relates to the age of the universe you must know the Hubble parameter today as well as the current ratio between the energy densities.
Could you show how - not quite sure how to do it.Orodruin said:Yes, you need to integrate the Friedmann equations to connect the scale factor to the age of the universe.
Looked into a few, but couldn't find the "integration of the Friedman equations to connect with age of the universe".Orodruin said:This should be described in any introductory level textbook on cosmology that discusses the Friedman equations.
I think it's a good question, Ranku. Why do you think Dark Energy varies over the age of the universe?Ranku said:Hmm...I am trying to calculate how the density of dark energy and matter varies over the age of the universe.
I was referring to how the comparative percentage of dark energy and matter changes over time - not in absolute terms, where only matter density decreases over time.Lindsayforbes said:I think it's a good question, Ranku. Why do you think Dark Energy varies over the age of the universe?
Ugh, man. Use the newest version. You're missing out on cool features, including graphing.stevebd1 said:http://www.einsteins-theory-of-relativity-4engineers.com/cosmocalc_2010.htm
adjust the redshift to see how the distribution of matter and dark energy has changed over the years
Bandersnatch said:Ugh, man. Use the newest version. You're missing out on cool features, including graphing.
Dark energy and matter density is a measure of the amount of energy and matter that is present in the universe but cannot be directly observed or detected. It is believed to make up the majority of the universe, with dark energy making up about 68% and dark matter making up about 27%.
The calculation of dark energy and matter density involves using various observational data, such as the expansion rate of the universe and the distribution of galaxies, to create models that can estimate the amount of dark energy and matter present. This process is complex and ongoing, as our understanding of the universe continues to evolve.
The existence of dark energy and matter has significant implications for our understanding of the universe. It helps to explain the observed expansion of the universe and the formation of structures such as galaxies and galaxy clusters. It also plays a role in the large-scale structure and evolution of the universe.
Dark energy is believed to be the driving force behind the acceleration of the expansion of the universe. This means that the more dark energy present, the faster the universe will expand. Dark matter, on the other hand, affects the expansion by providing the gravitational pull necessary for structures to form and hold together.
Scientists use a variety of tools and techniques to study dark energy and matter density, including telescopes, particle detectors, and computer simulations. They also collaborate with other researchers and analyze large datasets to better understand the properties and behavior of these elusive substances.