New Physics with Black HolesJulien GRAIN

Aurelien BARRAU, Gaelle BOUDOUL

What PBHs say about “standard” physics and

cosmology

• Formation and evaporation• Constraints from anti-protons fluxes• Detection with anti-deuterons• Cosmological constraints

PBH could have formed in the early universe

• Standard mass spectrum in the early universe

• Example of a near critical phenomena

PBHcBH

BHBH MM

MMn

2*

2/5

*

)2( PBHcBH

BHBH MM

MMn

2*

2/5

*

)2(

cHMM cHMM

Black Holes evaporate• Radiation spectrum

• Hawking evaporation law

kGM

hcT

16

3

2

)(

M

M

dt

dM

stGeVTgM

stGeVTgM

11010

10101049

21116

stGeVTgM

stGeVTgM

11010

10101049

21116

sTBk

Q

eh

QM

dQdt

Nd2

222

)1(

sTBk

Q

eh

QM

dQdt

Nd2

222

)1(

Direct antiprotons emission• Individual emission

• Convoluted with the mass spectrum today

dMdMdV

z)n(rd

dEdT

E)N(Md=E)z(rq prim ,,

,,22

dMdMdV

z)n(rd

dEdT

E)N(Md=E)z(rq prim ,,

,,22

dQdE

EQdge

h

TQ

dEdt

NdpjskT

Q

j EQ

jj

p),(

)1(),( __

1

2

2

*2 MMM

dM

dM

dM

dn=

dM

dn init

init

*2 MMM

dM

dM

dM

dn=

dM

dn init

init

3/13 3 )Mαt(M init 3/13 3 )Mαt(M init Initial spectrumInitial spectrum

Source flux

gM 1310 5 gM 1310 5

g]g[M 1313 10 5 ,10 g]g[M 1313 10 5 ,10

FL

UX

antiprotons kinetic energy (GeV)

g]g[M 1312 10 ,10 g]g[M 1312 10 ,10

g][MM Pl

12,10 g][MM Pl

12,10(1)

(2)

(3)

(4)

main contribution for :

*1312 10.510 MM *

1312 10.510 MM

No influence of the details of the formation mechanismNo influence of the details of the formation mechanism

Let antiprotons propagate in the Milky Way

Drawing by D. Maurin

Diffusive halo with convection and nuclear reaction

Diffusive halo with convection and nuclear reaction

Galactic disc where sources areGalactic disc where sources are

Maurin, Taillet, Donato, Salati, Barrau, Boudoul, review article for “Research Signapost” (2002) [astro-ph/0212111]

Primary and secondary antiprotons

• Solve a diffusive equation for PBHs antiprotons AND secondary antiprotons coming from nuclear reaction on the ISM:

• And taking into account the diffusion in energy (tertiary contribution)

),,(1

),0,()(2),0,()(22

2

_ EzrNr

rrzz

Kz

VErNzhErqzh cine

p

p-p interactionp-p interaction

p-He interactionp-He interaction

He-He interactionHe-He interaction

He-p interactionHe-p interaction

Top of the atmosphere fluxesExperimental data points

Secondary antiprotons flux : “standard” physics only

PBH antiprotons flux for different values of PBH’s density

A. Barrau, G. Boudoul et al., Astronom. Astrophys., 388, 767 (2002)

F.Donato, D. Maurin, P. Salati, A. Barrau, G. Boudoul, R.Taillet

Astrophy. J. (2001) 536, 172

Upper limit on the PBH density

33433 .105105 cmg )3(104 351 kpcLcmn )3(104 351 kpcLcmn

9104 PBH

9104 PBH

99%63%

Cosmological constrain:PBH fraction β

Antiprotons constrains

Barrau, Blais, Boudoul, Polarski, Phys. Lett. B, 551, 218 (2003)

Hypothesis: bump in the mass variance

cHMM cHMM

PBH is the only way to constrain small length scale in the primordial power spectrum

PBH is the only way to constrain small length scale in the primordial power spectrum

Detection of PBH:Antideuterons

evaporation

Secondary anti(D)

Window for detection

A. Barrau, G. Boudoul, et al. Astronom. Astrophys. 398, 403 (2003)

Future experiment like AMS or CREAM will measure the antideuteron flux Improvement ~ factor 10 insensitivity

Future experiment like AMS or CREAM will measure the antideuteron flux Improvement ~ factor 10 insensitivity

New physics with small Black Holes

• Gauss-Bonnet Black Holes at the LHC• Cosmic Gauss-Bonnet Black Holes

Gauss-Bonnet black holes at the LHC

We will see…

Let’s hope!!!

We will see…

Let’s hope!!!

Barrau, Grain & Alexeev Phys. Lett. B 584, 114-122

(2004)

Black Holes at the LHC ?Hierarchy problem in standard physics:

Two solutions:

Warped extra-dimensionnal geometries (RS)

Large extra dimensions

Harkani-Hamed, Dimopoulos, Dvali Phys. Lett. B 429, 257 (1998)

Randall, Sundrum Phys. Rev. Lett 83, 3370 (1999)

Black Hole Creation

• Two partons with a center-of-mass energy moving in opposite direction

• A black hole of mass and horizon radius is formed if the impact parameter is lower than

From Giddings & al. (2002)

Precursor Works

• Computation of the black hole’s formation cross-section

• Derivation of the number of black holes produced at the LHC

• Determination of the dimensionnality of space using Hawking’s law

Dimopoulos, Landsberg Phys. Rev. Lett 87, 161602 (2001)

Giddings, Thomas Phys. Rev. D 65, 056010 (2002)

From Dimopoulos & al. 2001

Gauss-Bonnet Black Holes?

• All previous works have used D-dimensionnal Schwarzschild black holes

• General Relativity:

• Low energy limit of String Theory:

Gauss-Bonnet Black Holes’ Thermodynamic (1)

Properties derived by:

Cai Phys. Rev. D 65, 084014 (2002)

Expressed in function of the horizon radius

Boulware, Deser Phys. Rev. Lett. 83, 3370 (1985)

Gauss-Bonnet Black holes’ Thermodynamic (2)

Non-monotonic behaviour

taking full benefit of evaporation process

(integration over black hole’s lifetime)

The flux Computation (theory)

• Analytical results in the high energy limit

The grey-body factors are constant

• is the most convenient variable

Harris, Kanti JHEP 010, 14 (2003)

The Flux Computation (ATLAS detection)

• Planck scale = 1TeV

• Number of Black Holes produced at LHC derived by Landsberg

• Hard electrons, positrons and photons sign the Black Hole decay spectrum

• ATLAS resolution

The Results -measurement procedure-

• For different input values of (D,), particles emitted by the full evaporation process are generated

spectra are reconstructed for each mass bin• A analysis is performed

2χ

The Results-discussion-

• For a planck scale of order a TeV, ATLAS can measure the dimensionnality of space and the Gauss-Bonnet coupling constant –at least distinguish between the case with and the case without Gauss-Bonnet term.

Important progress in the construction of a full quantum theory of gravity

• The results can be refined by taking into account more carefully the endpoint of Hawking evaporation

• The statistical significance of the analysis should be taken with care

2χBarrau, Grain & Alexeev

Phys. Lett. B 584, 114 (2004)

Future Studies• Include a cosmological constant

Motivated by the AdS and dS/ CFT correspondences

• The same study for spinning black holes

More realistic, as black holes produced at LHC are expected to be spinning

Qualitatively equivalent but quantitatively different

Alexeyev, Popov, Barrau, Grain in preparation

Cai hep-ph/0311020 (2003)

EDGB cosmic black holes• 4-dimensionnal string theory

• Change in the metric function

2

24

4

2

RRRRRS

SeRgxdS

ijij

ijklijklGB

GB

)sin( 222222

22 ddrdrdtds

Black hole minimal mass ~ few Planck massBlack hole minimal mass ~ few Planck mass

hhr 64inf hhr 64inf

Evaporation law and integrated relic flux

Hawking law

max

02

222

4

)(tan)(),1(

R

univ dRR

RR

c

RtzE

dEdt

NdF

max

02

222

4

)(tan)(),1(

R

univ dRR

RR

c

RtzE

dEdt

NdF

12117101.1 srmsJF12117101.1 srmsJF

Alexeyev, Barrau, Boudoul, Sazhin, Class. & Quantum Grav., 19, 4431 (2002)

Alexeyev, Barrau, Boudoul et al., Astronom. Lett., 28, 7, (2002)

Particle physics beyond the standard model with black

holes ?

A. Barrau & N. Ponthieu

Phys. Rev. D 69, 085010 (2004) , hep-ph/0402187

- To avoid entropy overproduction, an upper limit on Trh is obtainted with gravitinos- If cosmic-rays from PBHs are detected, it leads to an upper limit on the Hubble mass at reheating so it leads to a lower limit on Trh- Combining both lead to constrains on the gravitino mass

Lower limit on the gravitinoMass as a function of the PBHInduced anti(D) flux

Conclusion

Big black holes are fascinating…Big black holes are fascinating…

But small black holes are far more fascinating!!!But small black holes are far more fascinating!!!