What is the initial force of universe expansion?

AI Thread Summary
The initial force driving the universe's expansion at the Big Bang is primarily attributed to the energy released during the event itself. Dark energy becomes significant in influencing the expansion rate as the universe evolves, particularly when the expansion accelerates. Initially, the expansion was dominated by radiation and matter, but as the universe expanded and cooled, dark energy's role increased. The transition to dark energy's dominance is crucial for understanding the current accelerated expansion of the universe. This discussion highlights the complex interplay between these forces throughout cosmic history.
Ranku
Messages
433
Reaction score
18
When the universe started expanding at the big bang, was it mainly driven by the force of the big bang ? Does dark energy start to play the major role in driving the expansion only when it is accelerating?

(I would prefer to have this question answered by a PF Science Advisor or someone who actually knows about it.)
 
Space news on Phys.org

Thread 'Matter density right after the decoupling'

https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
View full post »

Thread 'Rutgers finds a transparent Einstein Cross - apparently a dark matter "halo".'

The formal paper is here. The Rutgers University news has published a story about an image being closely examined at their New Brunswick campus. Here is an excerpt: Computer modeling of the gravitational lens by Keeton and Eid showed that the four visible foreground galaxies causing the gravitational bending couldn’t explain the details of the five-image pattern. Only with the addition of a large, invisible mass, in this case, a dark matter halo, could the model match the observations...
View full post »

Thread 'Hubble Constant, Dark Energy and the Expanding Universe'

Why was the Hubble constant assumed to be decreasing and slowing down (decelerating) the expansion rate of the Universe, while at the same time Dark Energy is presumably accelerating the expansion? And to thicken the plot. recent news from NASA indicates that the Hubble constant is now increasing. Can you clarify this enigma? Also., if the Hubble constant eventually decreases, why is there a lower limit to its value?
View full post »

Similar threads

B Does an infinite universe contradict a Big Bang origin?
2
Replies
65
Views
6K
I Density fluctuations in a homogeneous linearly expanding universe?
Replies
7
Views
2K
I What Are the Origins of the Universe?
Replies
17
Views
3K
I Voids, dark energy and tidal forces...?
Replies
0
Views
2K
I Sachs-Wolfe effect in a Dark Energy universe?
Replies
1
Views
2K
I What is the acceleration of the expansion of the Universe?
Replies
7
Views
2K
B Estimates — True Size of the Universe?
Replies
17
Views
3K
B What is the relationship between expansion and curvature?
Replies
20
Views
3K
I Proton decay at the end of the Universe
Replies
13
Views
2K
I 3 questions about a paper on density fluctuations in the Universe
Replies
1
Views
2K

Hot Threads

Recent Insights

Back
Top