Since around 1997–2003, the problem is believed to have been solved by most cosmologists: modern cosmological measurements lead to a precise estimate of the age of the universe (i.e. time since the Big Bang) of 13.8 billion years, and recent age estimates for the oldest objects are either younger than this, or .
The first, and most perplexing, is the rate at which the universe expands, a value known as the Hubble constant.
For more than a decade, scientists have struggled to reconcile conflicting measurements of this rate, with some even calling the issue the biggest crisis in cosmology.Jul 25, 2023.
In cosmology, the cosmological constant problem or vacuum catastrophe is the substantial disagreement between the observed values of vacuum energy density (the small value of the cosmological constant) and the much larger theoretical value of zero-point energy suggested by quantum field theory..
'Early dark energy' could explain the crisis in cosmology In 1916, Einstein finished his theory of general relativity, which describes how gravitational forces alter the curvature of spacetime
Among other things, this theory predicted that the universe is expanding, which was confirmed by the observations of Edwin Hubble in 1929
You may have heard about the " cosmology crisis:" Different methods of measuring the age of the universe are giving different results, and cosmologists have no idea why
As an astrophysicist — and a cosmologist, to boot — I have my own take on this so-called crisis
But first, let's see what the problem is
We are eradicating diseases, venturing further into space and discovering a growing zoo of subatomic particles
But cosmology – which is trying to understand the evolution of the entire universe using theories that work well to describe other systems – is struggling to answer many of its most fundamental questions
