All Questions
42
questions
2
votes
0
answers
44
views
Feynman rule from dynamical Chern-Simons
Consider the following action that
\begin{equation}
S = \int d^4x\sqrt{-g}\left(-\frac{1}{2}(\partial\phi)^2 + V(\phi) + \frac{2R}{\kappa^2}
- \frac{\phi}{4f}{}^*RR\right)
\end{equation}
where
\...
- 714
0
votes
0
answers
97
views
If dark energy has constant density, would it still be subject to quantum variations; would increase/decrease be symmetrical, or would one take over?
There are different suggestions, but it stills seems like the basic scenario is for dark energy to have constant density, as a property of space (and as represented by the cosmological constant in ...
- 15
2
votes
0
answers
24
views
Why is there an infinite supply of energy in slow-roll inflation?
The physical model of inflation includes a metastable false vacuum, or a slow-roll field on a flat potential. In either case, I just realized how this is completely insane. With the exponential growth ...
- 619
0
votes
0
answers
52
views
False Vacuum State (QFT)
I am wondering if someone can refer me to a proof that the false vacuum state is a natural consequence of scalar field theories? I see that being said in a lot of texts on cosmology when discussing ...
- 1
3
votes
1
answer
362
views
What is the energy density of the inflaton field?
I am trying to compare the theoretically calculated vacuum energy density according to quantum field theory with the energy density of the inflaton field, in joules per cubic meter (or Pascal). I ...
- 65
2
votes
0
answers
75
views
Perturbative reheating
Are there any inflation models in which reheating would start perturbatively? I mean the non-perturbative process named as preheating (via parametric resonance) would be either inefficient or absent ...
- 3,691
2
votes
1
answer
329
views
Fokker-Planck equation from Langevin equation in stochastic inflation
I'm reading this paper by Starobinsky and Yokoyama where they give the coarse-grained equation of motion,
$$
\dot{\bar{\phi}}({\bf x},t ) = -\frac{1}{3H}V'(\bar{\phi}) + f({\bf x},t)
$$
where $f({\bf ...
- 574
0
votes
0
answers
89
views
Quantum fluctuations in the early universe
A Quanta Magazine article on the relationship between inflation and the large-scale structure of the universe mentions the relationship between the spatial distribution of galaxies and quantum ...
- 576
0
votes
2
answers
83
views
Are there introductory reviews of trans-Planckian physics and inflation? Looking for something similar to Daniel Baumann's cosmology notes
Are there introductory reviews of trans-Planckian physics and inflation? Looking for something similar to Daniel Baumann's cosmology notes - things are explained assuming minimal background.
2
votes
2
answers
125
views
How should we deal with interactions not from a “fundamental force”? [closed]
Question
Should the cosmological constant and/or vacuum energy be listed as one of the fundamental interactions?
If not, how can we have actual energy and forces that are not assignable to one of the ...
- 3,365
1
vote
1
answer
69
views
Is the inflation theory based on the inflaton field or electronuclear force carriers decay? [duplicate]
Some sources introduce the inflaton field as the cause of the inflation period in the big bang theory, and some others relate it to the decay of electronuclear bosons. Which one of these is ...
- 11
1
vote
1
answer
827
views
How are Dark Energy and the Inflaton Field related?
My understanding of Inflation Theory:
Before $10^{-35}$ seconds the universe began to cool and the Inflaton Field approached a false vacuum. When it reached this false vacuum, there was a constant ...
- 105
1
vote
0
answers
85
views
To which particles does the inflaton field preferably couple?
I am studying the (p)reheating dynamics and I would like to know if it is a reasonable assumption to consider a generic inflaton field (not the Higgs-inflaton) to be coupled with the same intensity to ...
6
votes
1
answer
1k
views
In-in (Schwinger-Keldysh) formalism in cosmology
I'm working on some application of the Schwinger-Keldysh formalism in cosmology (studying correlation function during inflation).
I saw both the operator and the path integral approach, maybe ...
- 900
3
votes
0
answers
139
views
Is it possible to treat fermion reheating from inflaton decay only perturbatively?
In case of an inflaton Lagrangian
$
\mathcal{L} = \frac{1}{2} (\partial_\mu \phi)^2 - \frac{1}{2}m_\phi^2 \phi^2 -h \overline{\psi} \phi \psi
$
where the inflaton field is coupled only to fermions ...