The early universe in a generalized theory of gravitation

Abstract

Dcp.pnr.trl7c.tit of'Physic..s, Urlivc,:\ity c?/ Torotrto, Tororlro. Orrr.. Cnritrdtr, M5S /A7 Rcccivcd September 8. 198 1 Thc standard Fricdn~ann-Robcrtson-Walker (FRW) big-bang modcl of thc univcrsc rcquircs spccial initial conditions: thc carly univcrsc is highly hornogcneous and isotropic cvcn though thcrc cxist causally disconncctcd regions (horizon problcm). A plane symmetric (anisotropic) solution of a systcm of field cquations in a gcncralizeci thcoly of gravitation, predicts thc beginning of thc univcrsc as a vacuum instability at a spccific fundamental timc (which can bc associated with thc Planck timc (t,)), after which matter is crcatcd as the univcrse bcgins to expand. At a time I = t, thcrc is a singular expansion, thc anisotropy vanishcs, and the physical horizon bcconlcs infinite. Thcrcafter thc solution of the field cquations gocs ovcr into thc F R W model. Thus the special initial conditions of thc FRW modcl at thc big-bang singularity t = t, arc prcdictcd by the thcory.LC modtlc big-bang standard Fricdrnan-Robcrtson-Walkcr (FRW) de I'univers rcquicrt dcs conditions initialcs spCcialcs: I'univcrs i son debut cst fortenlent homogene ct isotropc. n1i.m~ s'il conticnt dcs r6gions non rcli6cs causalcment (problemc d'horizon). Unc solution sy~nktriquc plane (anisotropc) d'un systcmc d'6quations de champ, dans une thCoric gCnkralis6e de la gravitation, pr6dit pour Ic commencement dc I'univcrs unc instabilitk du vide i un temps fondamcntal spkcifique (qui pcut Etrc associk avcc lc tc~nps dc Planck (t,,)), aprks quoi la maticre cst crC6c en mEmc temps quc I'univcrs commence son cxpansion. Pour un temps t = I,, il y a unc singularit6 diuns l'cxpansion. I'anisotropic disparait, ct I'horizon physiquc dcvient infini. Par la suite, la solution dcs equations du champ sc confond avcc Ic modelc FRW. La thCoric sc trouve donc h predirc lcs conditions initialcs sptcialcs du modclc FRW pour unc singularit6 dc big-bang i t = t c .[Tracluit par Ic journal] Can. J . Phys.. 60. 650 (1082)

Gravity, ghosts, and strings

“…18). Nonsymmetric gravitational theory is in agreement with all present-day gravitational experiments (18)(19)(20)(21)(22)(23)(24)(25)(26). The weak-field behaviour of N.G.T.…”

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“…By introducing the spin-projection operators (44) each field in the Lagrangian may be reduced into its irreducible spin components; in the present example, reduces A, into its spin-1-part and its spin-0+ part, respectively. For fields with more than one index, the irreducible JP pieces may be determined by taking decomposing product representations of 0 and w. The next step is to rewrite the Lagrangian in terms of these irreducible components; for the above 2, [26] …”

On the formation of star clusters in the merger NGC 6240

“…The high angular resolution of the HST resolved R136a in 30 Doradus, previously believed to be a single, hyper-massive star (cf. Moffat 1982;Savage et al 1983), into individual stars (Malumuth & Heap 1994, Hunter et al 1995. Subsequently, WFPC2 has been used to detect starburst sites and star-forming regions in nearby and distant galaxies.…”