1. local non-gaussianity from rapidly
varying sound speeds
Jon Emery
with Gianmassimo Tasinato and David Wands
arXiv: JCAP08(2012)005
COSMO12 – 13/9/2012

2. inflation and non-gaussianity multiple-dbi inflation
introduction
inflation and non-gaussianity
breaking the degeneracies
multiple-dbi inflation
affect of multiple sound speeds on
local type non-gaussianity
COSMO12 – 13/9/2012

3. inflation and non-gaussianity
komatsu et al. (2008)
COSMO12 – 13/9/2012

4. inflation and non-gaussianity
komatsu et al. (2008)
COSMO12 – 13/9/2012

5. inflation and non-gaussianity
komatsu et al. (2008)
COSMO12 – 13/9/2012

6. inflation and non-gaussianity
example: two field inflation
byrnes and tasinato (2008)
COSMO12 – 13/9/2012

7. inflation and non-gaussianity
example: dbi inflation
6D calabi-yau
alishahiha, silverstein and tong (2004)
COSMO12 – 13/9/2012

8. inflation and non-gaussianity
problem: degeneracy × × × × × × × × × × × × × × × × × ×
COSMO12 – 13/9/2012

9. inflation and non-gaussianity
problem: degeneracy × × × × × × × × × × × × ×
COSMO12 – 13/9/2012

10. inflation and non-gaussianity
fNL
wmap:
planck:
COSMO12 – 13/9/2012

11. inflation and non-gaussianity
vanilla
multiple fields
non-canonical
COSMO12 – 13/9/2012

12. multiple-dbi inflation
vanilla
multiple fields
non-canonical
COSMO12 – 13/9/2012

13. multiple-dbi inflation
vanilla
multiple fields
non-canonical
COSMO12 – 13/9/2012

14. multiple-dbi inflation
choose a model: two field dbi
COSMO12 – 13/9/2012

15. multiple-dbi inflation
background: hamilton-jacobi
same sound speeds at horizon crossing
COSMO12 – 13/9/2012

16. multiple-dbi inflation
perturbations: delta n and separable hubble
vernizzi & wands (2006)
byrnes & tasinato (2009)
COSMO12 – 13/9/2012

17. multiple-dbi inflation
results: analytical expression
COSMO12 – 13/9/2012

18. multiple-dbi inflation
results: analytical expression
COSMO12 – 13/9/2012

19. multiple-dbi inflation
results: analytical expression
COSMO12 – 13/9/2012

20. multiple-dbi inflation
results: analytical expression
COSMO12 – 13/9/2012

21. multiple-dbi inflation
results: analytical expression
byrnes & tasinato (2009)
COSMO12 – 13/9/2012

22. multiple-dbi inflation
results: analytical expression
byrnes & tasinato (2009)
COSMO12 – 13/9/2012

23. multiple-dbi inflation
results: inflation in two cut-off throats
warp factors
COSMO12 – 13/9/2012

24. multiple-dbi inflation
results: inflation in two cut-off throats
trajectories
COSMO12 – 13/9/2012

25. multiple-dbi inflation
results: inflation in two cut-off throats
sound speeds
COSMO12 – 13/9/2012

26. multiple-dbi inflation
results: inflation in two cut-off throats
non-linearity parameter
COSMO12 – 13/9/2012

27. multiple-dbi inflation
progress: equilateral contribution
third order action
path integral formalism
seery & lydsey (2005)
COSMO12 – 13/9/2012

28. multiple-dbi inflation
progress: equilateral contribution
equilateral non-linearity parameter
COSMO12 – 13/9/2012

29. multiple-dbi inflation
progress: equilateral contribution
equilateral non-linearity parameter
COSMO12 – 13/9/2012

30. inflation and non-gaussianity multiple-dbi inflation
conclusions
inflation and non-gaussianity
breaks the degeneracies of realistic models
multiple-dbi inflation
rapidly varying sound speeds can produce large
local type non-gaussianity
COSMO12 – 13/9/2012