Problems with the CDM Model

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Galaxy formation from the IIB Superstring with Fluxes Tonatiuh Matos http:/www.fis.cinvestav.mx/~tmatos. Problems with the  CDM Model. Dark Energy: Extreme fine tuning for  Coincidence Dark Matter: Cuspy central density profiles Too much substructure Too late galaxy formation - PowerPoint PPT Presentation

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Galaxy formation from the IIB Superstring with Fluxes

Tonatiuh Matos

http:/www.fis.cinvestav.mx/~tmatos

Problems with the CDM Model• Dark Energy:• Extreme fine tuning for • Coincidence

• Dark Matter: • Cuspy central density profiles• Too much substructure• Too late galaxy formation• Too early metalicity formation• Etc.

Some Alternatives• Self-Interacting DM • Warm DM• Super Heavy DM• Self-Annihilating DM• Repulsive DM• Fuzzy DM• Decaying DM

• Scalar Field Dark Matter

• V = V0 (cosh()-1)

Cosmology from Superstrings Theory

• R. Brandenberger

• R. Kallosh

• D. Wands, etc.

Cosmology from Superstrings Theory

• R. Brandenberger

• R. Kallosh

IIB Superstrings theory with FluxesPhys.Rev.D67:046006,2003

• Type IIB Superstrings With Fluxes

Bose-Einstein Condensate

+ dV/d = 0

• V = V0[cosh() – 1]

Bose-Einstein Condensates

• Tc TeV

• m < 10-17 eV

• Mcrit 0.1 M2Planck /m

Scalar Field Fluctuation = HaloTonatiuh Matos and F. Siddhartha Guzman Class. Q. Grav. 17(2000)L9;

Tonatiuh Matos, F. Siddhartha Guzman and Dario Nuñez, Phys. Rev. D62(2000)061301(R);

Tonatiuh Matos and F. Siddhartha Guzman, Class.Q. Grav. 18(2001)5055

• M 0.1 M2Planck /m

• If m 10-23 eV

• M 1012 Mo

The ModelT. Matos, R. Luevano, H. H. Garcia Compean.

• V = V0[cosh() – 1] +Axion

• exp() 2

• Inflation

• hin

u

Omegas

Omegas

exp() zoom

Direct Proof of DM (Chandra)

Density Profiles

Density Profiles

LSB Galaxies

Density Profiles

LSB Galaxies

Summarizing

• The IIB Superstring model:

• Behaves as CDM after recombination.

• Reproduces all the successes CDM above galactic scales.

• Predicts a sharp cut-off in the mass power spectrum

• The favored values for the two free parameters 20 V0 (310-27 Mpl )4 m 10-23 eV

Conclusions

• The differences between IIB superstrings and CDM:

• 1) Recombination

• 2) Center of the Galaxies

Conclusion

• The Dilaton could be a good candidate to be the Dark Matter of

the Universe