Cosmology
45. Quantization of cosmological perturbations. Mukhanov-Sasaki variable (Inflationary perturbations 5)
I introduce Mukhanov-Sasaki variable, show how to quantize inflationary perturbations and again calculate the power spectrum of primordial perturbations – by QFT this time.
44. Cosmological perturbations in the presence of scalar field (Inflationary perturbations 5)
I discuss cosmological perturbation theory in the Universe where the dominant component of matter is a scalar field. It is show that spectrum of inflationary perturbations is nearly flat.
40. Inflation: field-theoretic description (Inflationary perturbations 4)
I discuss simplest field theoretic models of inflation, dynamics of inflation at the level of background and Hamilton-Jacobi formalism for inflation.
38. And again about effective QFT for inflation
I show that effective QFT corrections to correlator of Mukhanov variable found by Armedariz-Picon et al. are due to effects of eternal inflation.
36. Eye on ArXiv: 6 May 2008 – Where does the cosmological perturbation theory actually break down?
I discuss the issue of cosmological perturbation theory breakdown and its relation to the regime of eternal inflation
34. Several questions about de Sitter
I ask several questions about Green’s functions on de Sitter
32. Eye on ArXiv: 30 Apr 2008 – Curvature perturbation from false vacuum inflation
Power spectrum of primordial perturbations is calculated for inlationary models with false minima of the inflaton potential.
30. Eye on ArXiv: 30 Apr 2008 – Effective QFT for inflation
Today, I think, the most interesting paper in ArXiv is the one by Steven Weinberg called “Effective field theory for inflation“. I would say, it generalizes results by Cheung et al. (their paper has a somewhat similar title 
) to larger effective cutoffs.
Read more on 30. Eye on ArXiv: 30 Apr 2008 – Effective QFT for inflation…
29. Eye on ArXiv: 28 Apr 2008 – D3/D7 brane inflation
I would like to briefly discuss the paper
released last friday. As follows from the title, the paper is about 
inflationary scenario ( and it is huge).
Read more on 29. Eye on ArXiv: 28 Apr 2008 – D3/D7 brane inflation…
28. Eye on ArXiv: 24 Apr 2008 – dS vacua in no-scale SUGRA; multifield DBI inflation
Laura Covi et al., de Sitter vacua in no-scale supergravities and Calabi-Yau string models; D. Langlois et al., Primordial fluctuations and non-Gaussianities in multi-field DBI inflation
27. Eye on ArXiv: 24 Apr 2008 – Detection of dark matter?
There was a lot of buzz recently (including the paper in New York Times) concerning the claim by DAMA/LIBRA team – they detected dark matter interactions with their detector at the level of 8 sigma
Read more on 27. Eye on ArXiv: 24 Apr 2008 – Detection of dark matter?…
25. Geometry and causal structure of de Sitter space (Inflationary perturbations 4)
I discuss geometry, causal structure and behavior of QFT Green functions in de Sitter space
24. Inflation: description in terms of hydrodynamics (Inflationary perturbations 4)
This post continues my lecture notes on large scale structure, cosmological perturbations and inflation. The last post in this series was about the problem of initial conditions in FRW cosmology. As we have found out, standard Hot Big Bang model with power law expansion 
is unable to explain present degree of homogeneity and isotropy of the Universe, so power law expansion of the Universe cannot be complete picture.
Read more on 24. Inflation: description in terms of hydrodynamics (Inflationary perturbations 4)…
23. Eye on ArXiv: 21 Apr 2008 – SUSY/non-SUSY duality
And so the new week began… Would be fun to finish another paper till Friday (the subject is “IR divergencies in de Sitter space”). In the mean time, let us take a closer look on some papers released to arxives during the previous week.
Read more on 23. Eye on ArXiv: 21 Apr 2008 – SUSY/non-SUSY duality…
22. About decoherence in quasi de Sitter space
My discussion of disorder on the landscape with Lubos continues (L – Lubos, D – me).
L: So if I understand well, your degree of freedom is really the inflaton phi, and it is one degree of freedom per Hubble patch, with one expectation value and one variation. The value of the inflaton is assumed to directly control the Hubble constant and the size of the patch, according to the normal equations.
Read more on 22. About decoherence in quasi de Sitter space…
Loading ...