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spidey
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What is the value of acceleration of universe? like Earth's gravitational acceleration is around 9.8 m/s2..has anyone found this value?
spidey said:What is the value of acceleration of universe? like Earth's gravitational acceleration is around 9.8 m/s2..has anyone found this value?
spidey said:Thanks Marcus..You have given information more than i asked..Why i asked this is, i want to compare unruh effect and CMBR..since universe is accelerating, the galaxies should be getting the thermal unruh radiation as per their acceleration and so if i get the acceleration of galaxies, i can get the unruh temperature and i wanted to see whether this is same as CMBR temperature 2.7K. Just a thought. You have any information with unruh temperature and CMBR temperature..
marcus said:Unruh temperature doesn't apply to cosmological expansion of distances.
For unruh temp, you need real motion and some quite substantial acceleration in a local inertial frame.
In the first place, the distant galaxies are not moving much, negligible speeds of just a few hundred km/s as far as we've been able to tell.
And on top of that, they have trivial acceleration, essentially zero, in any local inertial frame.
Of course the distances from us to them are increasing, often at rates several times the speed of light, but that is just General Relativity change in geometry, has nothing to do with Unruh effect.
It might help if you had a look at the cosmo basics sticky thread in cosmo forum
spidey said:Thank you very much for your clear explanation..
The value of acceleration in the accelerating universe is measured by the Hubble constant, which is currently estimated to be around 70 km/s/Mpc. This means that the universe is expanding at a rate of 70 kilometers per second for every megaparsec (3.26 million light years) of distance.
The value of acceleration is determined through various observations and measurements, such as the redshift of distant galaxies and the cosmic microwave background radiation. These measurements are then used to calculate the expansion rate of the universe and determine the value of acceleration.
The accelerating universe is significant because it provides evidence for the existence of dark energy, a mysterious force that is causing the expansion of the universe to accelerate. This discovery has major implications for our understanding of the fundamental laws of physics and the future fate of the universe.
The value of acceleration directly affects the expansion of the universe. A higher value of acceleration means that the expansion of the universe is accelerating at a faster rate, while a lower value of acceleration would result in a slower expansion. This has important implications for the ultimate fate of the universe.
While the value of acceleration is currently measured to be around 70 km/s/Mpc, it is possible that this value may change over time. This is because the nature of dark energy is still not fully understood, and it is possible that its properties may change as the universe continues to expand. Further research and observations are needed to better understand the dynamics of the accelerating universe and the role of dark energy.