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PRESENT STATUS OF THE ATTEMPTS AT A REALISTIC GUT IN EXTENDED SUPERGRAVITY

THEORIES

M. Günaydin

To cite this version:

M. Günaydin. PRESENT STATUS OF THE ATTEMPTS AT A REALISTIC GUT IN EXTENDED SUPERGRAVITY THEORIES. Journal de Physique Colloques, 1982, 43 (C3), pp.C3-328-C3-330.

�10.1051/jphyscol:1982366�. �jpa-00221921�

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JOURNAL DE PHYSIQUE

CoZZoque C3, suppZ6ment au n o 12, Tome 43, de'cembre 1982 page C3-328

PRESENT STATUS OF THE ATTEMPTS AT A R E A L I S T I C GUT I N EXTENDED SUPERGRAVITY THEORIES

CERN, Geneva, SwitzerZmd

The l a r g e s t extended supergravity theory (ESGT)

( N =

8 ) as written down by Cremmer and J u l i a has an on-shell E7(7)global x SU(8)local invariance

[

1-3 1 . In the "gauged" version of the theory a s given by De Wit and Nicolai t h e on-shell E7(7)

global

invariance i s l o s t and one has an S0(8)loca1 x SU(8)1 oc invariance on the Lagrangian level [4 I . Below, we shall r e s t r i c t ourselves t o the "ungauged"

version of the

N = 8

ESGTC 5 1 .

AshasobservedbyGell-Elann

[6 1 , the fundamental f i e l d s of the

N =

8 ESGT do not have .a rich enough s t r u c t u r e t o accommodate the basic f i e l d s of a r e a l i s t i c gauge theory of strong, weak and electromagnetic interactions and thus t o make contact with elementary p a r t i c l e phenomenology some of the f i e l d s entering such a gauge theory night have t o be made composite C7 1 . The f i r s t important development i n t h i s direction came from Cremmer and J u l i a who suggested t h a t the c l a s s i c a l l y non-propagat- ing composite gauge f i e l d s of SU(8)10ca1 nay become dynamical on the quantum level D l . Their suggestion was motivated by the analogy with two-dimensional

C P ~

models whose study a t l a r g e

N

l i m i t shows t h a t the composite gauge f i e l d develops a pole a t

p2 = 0

i n i t s propagator and hence becomes dynamical on the quantum level [81 . The same phenomenon has been shown t o occur in three-dimensional supersymmetric non- l i n e a r sigma models [91 . The suggestion of Cremmer and J u l i a motivated the study of SU(8) a s a possible

GUT

group 1101 .

The next important attempt t o make contact with p a r t i c l e physics came from E l l i s , Gaillard, Maiani and Zumino (EGMZ) who suggested t h a t in the

N = 8

ESGT, in addition t o massless gauge f i e l d s , other massless bound s t a t e s (fermionic and bosonic) may form whose low energy e f f e c t i v e theory i s a

GUT

based on SU(5) with three

generations of quarks and leptons

[

11 - 12 1 . All the "elementary" p a r t i c l e s entering t h i s GUT (quarks, leptons, gauge f i e l d s , Higgs f i e l d s ) a r e composites of the basic f i e l d s of the N

= 8

ESGT (referred t o as haplons o r preons) with a binding scale of the order of

14planck.

In the candidate "super GUT" proposed by E l l i s , Gaillard, and Zumino 112 I-(EGZ) t h e "elementary" p a r t i c l e s were chosen from the "gauge super multiplet" of bound s t a t e s which containsthe 63 gauge f i e l d s of SU(8),o, C131 .

However, theUgauge super rdul t i p l e t " contains many unwanted he1 i c i t y s t a t e s a s we1 1.

In f a c t , t o give SU(5) or SU(3)C x SU(2)W x U(1) invariant superheavy masses (of the order of

Flp

or MGU) to t h e unwanted h e l i c i t y s t a t e s and be l e f t with three massless chiral families of quarks and leptons i s a major problem of the

EGZ

scheme

112,

14-171and of the subsequent attempts t o extend i t 118-191 . In t h e i r recent important work related t o t h i s problem A l t a r e l l i , Cabibbo and Maiani have shown t h a t i t i s possible t o give SU(3)C x U(1) invariant masses t o a l l the members of a f i n i t e number of massless N

=

8 supermultiplets without, a t the same time, the mass matrix being SU(8) invariant

[

201 . However doing so e n t a i l s problems w i t h exotic SU(5) representations f o r s

=

1/2 bound s t a t e s and/or low mass

( z Flw)

high h e l i c i t y bound s t a t e s which have not been observed. The problem of unwanted h e l i c i t y s t a t e s can be solved t r i v i a l l y i f one assumes i n f i n i t e supermultiplets of bound s t a t e s 1141. In f a c t , there a r e many theoretical arguments f o r the possible existence of an i n f i n i t e s e t of bound s t a t e s i n ESGTs [14-17, 21,221 . One argument i s the

)ti P r e s e n t a d d r e s s : L a b o r a t o i r e d e P h y s i q u e Thgorique d e 1 ' ~ c o l e Normale Supdrieure, 24, r u e Lhomond, 75231 P a r i s Cedex 05, F r a n c e

Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:1982366

(3)

M. Giinaydin C3-3 2 9

r e g g e i z a t i o n o f s c a t t e r i n g amplitudes i n ESGT s [23]

.

Another argument i s based on t h e f a c t t h a t i n two 124,251 and three-dimensional 1 9 1 g e n e r a l i z e d n o n - l i n e a r sigma models t h e bound s t a t e s f a l l i n t o l i n e a r r e p r e s e n t a t i o n s o f t h e g l o b a l i n v a r i a n c e group. I f t h e same phenomenon occurs i n four-dimensional t h e o r i e s then one expects i n f i n i t e towers o f bound s t a t e s i n ESGT s f o r

N

= 4

-

8 s i n c e t h e i r g l o b a l i n v a r i a n - ce groups a r e non-compact [17, 261

.

The r e l e v a n t u n i t a r y r e p r e s e n t a t i o n s must be those t h a t can be constructed u s i n g t h e f i e l d operators o f these t h e o r i e s . The o s c i l l a t o r - l i k e u n i t a r y r e p r e s e n t a t i o n s o f t h e non-compact groups o f ESGT s (N = 4

-

8 ) have been constructed using boson a n n i h i l a t i o n and c r e a t i o n operators, t r a n s f o r m i n g l i k e t h e i r v e c t o r f i e l d s 127,281

.

One can a l s o c o n s t r u c t t h e u n i t a r y r e p r e s e n t a t i o n s o f these groups over t h e s c a l a r f i e l d s i n t h e r e s p e c t i v e t h e o r i e s [22, 291

.

Remarkably enough, i n b o t h cases one o b t a i n s t h e same c l a s s o f u n i t a r y r e p r e s e n t a t i o n s [ 29, 30 ]

.

I n t h e unitar.y qauqe which i s m a n i f e s t l y f r e e o f clhosts, t h e qenerators o f t h e non-compact group a c t i o n p r e s e r v i n g t h i s gauge do n o t commute w i t h supersymmetry generators [ 14, 22 ]

.

The l a r g e r algebra i n t o which t h e y c l o s e i s an i n f i n i t e - dimensional superalgebra i n v o l v i n g generalized supersymmetry generators and general- i z e d momenta 122 ]. The r e s u l t i n g i n f i n i t e superalgebras have been w r i t t e n down f o r N = 4 and

N

= 8 ESGT s i n t h e r i g i d l i m i t o f s p a t i a l i n f i n i t y where a l l f i e l d s vanish a s y m p t o t i c a l l y except f o r t h e s c a l a r f i e l d s and t h e v i e r b e i n [ 2 2 ]

.

I f

indeed t h e bound s t a t e s o f a given h e l i c i t y f a l l i n t o u n i t a r y r e p r e s e n t a t i o n s o f t h e non-compact i n v a r i a n c e group then t h e bosonic and f e r m i o n i c bound s t a t e s t o g e t h e r must correspond t o a u n i t a r y r e a l i z a t i o n of t h i s i n f i n i t e superalgebra. The u n i t a r y r e a l i z a t i o n s o f t h e i n f i n i t e superalgebra generated by non-compact SU(1,l) and supersymmetry generators i n t h e

N

= 4 case have been i n v e s t i g a t e d on t h e " c l a s s i c a 1 "

l e v e l 122 1

.

One f i n d s t h a t t h e a c t i o n o f a generalized supersymmetry generator maps a s t a t e belonging t o a u n i t a r y r e p r e s e n t a t i o n w i t h h e l i c i t y A i n t o a s t a t e belonging t o a u n i t a r y r e p r e s e n t a t i o n w i t h h e l i c i t y A

+

1/2. I f on t h e quantum l e v e l t h e i n t e g r a t e d charges o f these generalized supersymmetry t r a n s f o r m a t i o n s a r e a l l u n i t a r i l y i n e q u i v a l e n t then one w i l l have an i n f i n i t e s e t o f generalized supercharges i m p l y i n g bound s t a t e s o f a r b i t r a r i l y l a r g e h e l i c i t y 1 221. T h i s i s c o n s i s t e n t w i t h t h e r e g g e i z a t i o n o f s c a t t e r i n g amplitudes i n ESGT s and t h e f a c t t h a t these i n f i n i t e superalgebras correspond t o g e n e r a l i z a t i o n s o f Kac-Moody algebras o r s t r i n g algebras.

I f t h e bound s t a t e s o f extended s u p e r g r a v i t y t h e o r i e s do indeed correspond t o u n i t a r y r e a l i z a t i o n s o f t h e i n f i n i t e superalgebras generated by t h e i r non-compact symmetry and supersymmetry generators, then a l l t h e ESGT s f o r N b 5 can i n p r i n c i p l e accommodate a r e a l i s t i c GUT based on SU(5) as an e f f e c t i v e "low energy" theory.

However, t h e N = 8 ESGT may t u r n o u t t o be t h e o n l y p h y s i c a l l y v i a b l e t h e o r y when one faces t h e c r u c i a l q u e s t i o n o f how these l a r g e symmetries break i n such a way as t o be l e f t w i t h t h e observed SU(3)C x SU(2)k, x U(1) symmetry (and p o s s i b l y a simple supersymmetry) and t h e r i g h t spectrum of "elementary p a r t i c l e s " a t low energies.

REFERENCES

[ l j Cremmer E., J u l i a B. and Scherk J., Phys. L e t t . 768 (1978) 409 [ 2 ] Cremmer E. and J u l i a B., Phys. L e t t . 808 (1978)

[ 3 ] Cremmer E. and J u l i a B., Nucl

.

Phys. m 9 (1979) 141

[ 4 ] de W i t B. and N i c o l a i H., Phys. L e t t . l 0 8 8

-

(1981) 285 ; Nucl. Phys. B, t o be pub1 i s h e d

[ 5 ] Gauging t h e SO(8) i n v a r i a n c e i n t r o d u c e s a l a r g e cosmological constant and t h e p o t e n t i a l becomes unbounded

C61 Gell-Mann I$., T a l k a t t h e 1977 Washington Meeting o f t h e American Physical Society, unpublished

C71 Gell-Mann M., T a l k a t t h e Aspen Workshop on Octonionic Quantum Mechanics (1978), unpublished

1 8 1 DIAdda

A.,

D i Vecchia P. and Liischer Il., Nucl. Phys.

8146

(1978) 63 ;

B152

(1979) 129

( 9 1 Nissimov E.R. and Pacheva S . J

. ,

Comptes Rendus de 1 'Academic Bulgare des S c i e n c e s 2 (1979) 1475 and L e t t . Flath. Phys. 5 (1981) 67, 333

[ 10 1 C u r t r i g h t T. and Freund P.G.O., "Supergravity", ed. by van Nieuwenhuizen P. and Freedman D.Z., North Holland, Amsterdam (1979) 197

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(23-330 JOURNAL DE PHYSIQUE

I11 I E l l i s J., G a i l l a r d M.K., Maiani L. and Zumino B., " U n i f i c a t i o n o f t h e Funda- mental P a r t i c l e I n t e r a c t i o n s " ed. by E l l i s J., F e r r a r a S. and van Nieuwenhuizen P., Plenum Press, N.Y. (1980)

[ I 2 1 E l l i s J., G a i l l a r d t1.K. and Zumino B., Phys. L e t t . 948 (1980) 343

[ I 3 1 E l l i s , G a i l l a r d and Zumino argued t h a t t h e "gauge s u p e r m u l t i p l e t " m i g h t be t h e same as the supercurrent m u l t i p l e t . However, t h i s has been shown n o t t o be t h e case by e x p l i c i t c a l c u l a t i o n . Cremmer E., p r i v a t e communication.

I 1 4 1 E l l i s J., G a i l l a r d M.K. and Zumino B., LAPP p r e p r i n t TH 44/ CERN TH 3152 (1981) t o appear i n Acta Physica Polonica

I 1 5 1 E l l i s J. i n " F i r s t Workshop on Grand U n i f i c a t i o n " , ed. by Frampton P., Glashow S.L. and Y i l d i z A., Math. S c i . Press, B r o o k l i n e (1980) 287 and CERW p r e p r i n t TH 3206 (1981), t o appear i n t h e proceedings o f t h e "Second Europhysics Study Conference on U n i f i c a t i o n o f t h e Fundamental I n t e r a c t i o n s "

Erice, October 1981

I 1 6 1 G a i l l a r d M.K., t a l k presented a t t h e Heisenberg Symposium, Munchen 1981, LBL p r e p r i n t LBL-13371 (1981)

I 1 7 1 Zumino

B.,

Proceedings 1980 Madison I n t e r n a t i o n a l Conference on High Energy Physics, ed. by Durand L. and Pondrom L.G., A.I.P., New York (1981) p 964 ; and "Superspace and Supergravity" ed. by Hawking S.W. and ~ o ? e k M., Cambridge U n i v e r s i t y Press, Cambridge (1981) p 423

[18l.Derendinger J.P., F e r r a r a S. and Savoy C.A., Nucl. Phys. 6188 (1981) 77 [19 1 Kim J. E. and Song H.S., Seoul National U n i v e r s i t y preprint-(r981)

L201 A l t a r e l l i G., Cabibbo N. and Maiani L., Rome U n i v e r s i t y p r e p r i n t 1982

I 2 1 1 Ginaydin M., CERN p r e p r i n t TH 3222 (1981) t o appear i n t h e proceedings o f t h e

"Second Europhysics Study Conference on U n i f i c a t i o n o f t h e Fundamental I n t e r - actions", E r i c e October 1981

I 2 2 1 E l l i s J., G a i l l a r d H.K., Gunaydin M. and Zumino B., i n p r e p a r a t i o n [23 1 G r i s a r u F.I.T. and S c h n i t z e r H.J., Nucl. Phys. B204 (1982) 267 [24 1 Bardeen W.A., Lee B.W. and Schrock R.E., P h y s x e v . D l 4 (1976) 985 125 I Haber H., H i n c h l i f f e I. and Rabinovici E., Nucl. P h y c B 1 7 2 (198C) 458

[26 I Bardeen U., unpublished and -

Gel 1 -1lann M., unpubl ished and R a b i n o v i c i E., unpublished

E27 1 Gunaydin M. and Saclioglu C., Phys. L e t t . 1086 (1982) 169

1281 Gunaydin M. and S a ~ l i o g l u C., CERN p r e p r i n m 3209 (1981), t o be published i n Comm. Math. Phys.

[291 Giinaydin

N.,

i n p r e p a r a t i o n

[ 3 0 ] Bars I. and GUnaydin M., CERN p r e p r i n t TH 3350 (1982)

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