9 Questions 16 Answers 0 Followers
Questions related from Ali Rida Khalife
In the book "Introduction to Quantum Effects in Gravity" by Mukhanov and Winitzki, chapters 6.6 and 6.7, a comparison of the amplitude of fluctuations of a scalar field between vacuum and an...
24 March 2020 2,890 0 View
In Newtonian mechanics, this relation is derived simply by matching the gravitational force to the centrifugal one. How can one get such a relation in GR? Is it derived from Einstein's equations...
15 July 2019 5,407 48 View
According to Mukhanov's "Physical foundations of cosmology" (page 230), to solve the Horizon and flatness problems, the rate of change of the scale factor today should be greater than the rate of...
15 April 2015 1,090 17 View
In most of the inflationary models, or quintessence models, a scalar field has been used to describe the dynamics. Why is this? I know that some models use vector fields, but if you want to use...
05 March 2015 7,134 11 View
It is stated in V. Mukhanov's book "Physical foundations of Cosmology" the following (page 44, after equation 2.25): "In contrast, for the dust dominated universe, where ηmax=2π, the event horizon...
20 January 2015 6,478 6 View
In Jacob Bekenstein's paper "Black Holes and Entropy", Hawking's area theorem is stated as follows: "Hawking has given a general proof that the black-hole surface area cannot decrease in any...
21 May 2014 7,220 4 View
I heard this idea and I wanted to check, but there was no good source on the internet. A good reference would be appreciated
11 May 2014 8,861 14 View
Imagine that I'm jumping over an infinite cliff, under the influence of the gravitational force(F=mg, where m is my mass and g is the gravitational constant). At some point, due to the...
13 January 2014 7,814 1 View
The gravitational field of a black hole is so strong that nothing, not even light (the limit of all speeds), can escape. Yet we still see jets of matter coming out of a black hole....
28 November 2013 5,628 44 View
