메뉴 건너뛰기




Volumn 58, Issue 4, 1998, Pages

Evolution of the scale factor with a variable cosmological term

Author keywords

[No Author keywords available]

Indexed keywords


EID: 0542446513     PISSN: 15507998     EISSN: 15502368     Source Type: Journal    
DOI: 10.1103/PhysRevD.58.043506     Document Type: Article
Times cited : (550)

References (138)
  • 10
    • 85038975019 scopus 로고    scopus 로고
    • See for example
    • See for example 92. New data from the Hipparcos satellite has, however, removed some of the need for an older universe by dramatically lowering estimates of globular cluster ages 82.
  • 11
    • 85039008299 scopus 로고    scopus 로고
    • See also L. M. Krauss, Los Alamos report astro-ph/9706227(1997).
    • (1997)
    • Krauss, L.M.1
  • 13
    • 85038997179 scopus 로고    scopus 로고
    • See for example
    • See for example 1457. Such models are not subject to the well-known singularity theorems [S. W. Hawking and G. F. R. Ellis, The Large Scale Structure of Spacetime (Cambridge University Press, Cambridge, England, 1973)] because the cosmological term (Formula presented) gives rise to a negative pressure (Formula presented) which is large enough to violate the strong energy condition 13.
  • 18
    • 85039031758 scopus 로고    scopus 로고
    • Note that the Hubble expansion, cosmic microwave background radiation and nucleosynthesis do not in themselves suffice to rule out nonsingular models, as is sometimes suggested
    • Note that the Hubble expansion, cosmic microwave background radiation and nucleosynthesis do not in themselves suffice to rule out nonsingular models, as is sometimes suggested 5. These phenomena imply that the Universe was once smaller, hotter and more dense than it is now — but do not demand that it began with zero size 98.
  • 27
    • 0003446393 scopus 로고
    • G. W. Gibbons, S. W. Hawking, S. T. C. Siklos, Cambridge University Press, Cambridge, England
    • A. D. Dolgov, in The Very Early Universe, edited by G. W. Gibbons, S. W. Hawking, and S. T. C. Siklos (Cambridge University Press, Cambridge, England, 1983), p. 449.
    • (1983) The Very Early Universe , pp. 449
    • Dolgov, A.D.1
  • 40
    • 85038975234 scopus 로고    scopus 로고
    • A. D. Dolgov, Los Alamos report astro-ph/9708045(1997).
    • (1997)
    • Dolgov, A.D.1
  • 47
    • 85038983976 scopus 로고    scopus 로고
    • Note also W. Unruh, Los Alamos report astro-ph/9802323(1998).
    • (1998)
    • Unruh, W.1
  • 50
    • 0000315585 scopus 로고
    • The history of this argument may be traced back at least to É. B. Gliner’s suggestion [Sov. Phys. JETP 22, 378 (1966)] that the vacuum be treated as a form of matter; namely a perfect fluid with (Formula presented).
    • (1966) Sov. Phys. JETP , vol.22 , pp. 378
  • 51
    • 0001674607 scopus 로고
    • The same treatment was rapidly extended to “(Formula presented)-matter” by Y. B. Zel’dovich [Sov. Phys. Usp. 11, 381 (1968)].
    • (1968) Sov. Phys. Usp. , vol.11 , pp. 381
    • Zel’dovich, Y.B.1
  • 52
    • 50249200211 scopus 로고
    • The consequent realization that (Formula presented) might vary was made by Linde in 1974 18, and placed in the full context of the cosmological “constant” problem by Polyakov and Adler in 1982 22. The first concrete mechanism for a variable (Formula presented) term (based on a nonminimally coupled scalar field) was proposed by Dolgov in 1983 23. It is interesting to note the prevalence of Soviet scientists in this list, and tempting to speculate about a possible connection with the philosophy of dialectical materialism. According to this school of thought, reality is (1) wholly material and (2) in a constant state of motion or change (the dialectical process). From this perspective it might seem natural to treat the cosmological term as (1) part of the matter content of the Universe, and (2) a dynamical quantity. A philosophical idealist, by contrast, might have preferred to treat (Formula presented) as a constant of nature, part of the pure “marble of geometry” on the left-hand side of the field equations [A. Einstein, J. Franklin Inst. 221, 349 (1936)]. A third approach is to let (Formula presented) vary while keeping it on the left-hand side of the field equations. It is possible to retain the conservation law (Formula presented) for ordinary matter in the usual manner. However, one is obliged to introduce new terms into the field equations (2.1), since the Bianchi identities guarantee the vanishing covariant divergence of the Einstein tensor (Formula presented) In scalar-tensor 17 and modified Brans-Dicke approaches 1934, for example, these additional terms are functions of a new scalar field.
    • (1936) J. Franklin Inst. , vol.221 , pp. 349
    • Einstein, A.1
  • 56
    • 85038290532 scopus 로고
    • “Stiff” matter with (Formula presented), for example, has been discussed in the context of a cold baryonic Universe [Y. B. Zeldovich, Mon. Not. R. Astron. Soc. 160, 1P (1972)]
    • (1972) Mon. Not. R. Astron. Soc. , vol.160
    • Zeldovich, Y.B.1
  • 57
    • 33749833011 scopus 로고
    • the early hadron era [B. J. Carr, Astrophys. J. 201, 1 (1975)]
    • (1975) Astrophys. J. , vol.201 , pp. 1
    • Carr, B.J.1
  • 58
    • 0000855426 scopus 로고
    • and scalar field fluids [M. S. Madsen, Phys. Rev. D 46, 1399 (1992)].
    • (1992) Phys. Rev. D , vol.46 , pp. 1399
    • Madsen, M.S.1
  • 59
    • 0000703965 scopus 로고
    • Proposed varieties of “soft” matter with (Formula presented) include cosmic string networks [J. R. Gott III and M. J. Rees, Mon. Not. R. Astron. Soc. 227, 453 (1987)].
    • (1987) Mon. Not. R. Astron. Soc. , vol.227 , pp. 453
    • Gott, J.R.1    Rees, M.J.2
  • 60
  • 61
    • 18144389049 scopus 로고
    • and quantum zero-point fields [P. S. Wesson, Phys. Essays 5, 561 (1992)]
    • (1992) Phys. Essays , vol.5 , pp. 561
    • Wesson, P.S.1
  • 62
    • 0000008340 scopus 로고    scopus 로고
    • all with (Formula presented); as well as “(Formula presented)CDM” (for “unknown cold dark matter”) with (Formula presented) [M. S. Turner and M. White, Phys. Rev. D 56, R4439 (1997)]
    • (1997) Phys. Rev. D , vol.56
    • Turner, M.S.1    White, M.2
  • 64
    • 16044372481 scopus 로고    scopus 로고
    • Fluids with values of (Formula presented) less than 2/3 might be termed “inflationary matter” [Eq. (2.8)]. Even negative values of (Formula presented) have been contemplated 7. The importance of the (Formula presented) parameter in observational cosmology has been emphasized by P. J. Steinhardt [Nature (London) 382, 768 (1996)].
    • (1996) Nature (London) , vol.382 , pp. 768
    • Steinhardt, P.J.1
  • 65
    • 0000372551 scopus 로고
    • Y.-K. Lau, Aust. J. Phys. 38, 547 (1985).
    • (1985) Aust. J. Phys. , vol.38 , pp. 547
  • 72
    • 4243828303 scopus 로고
    • A.-M. M. Abdel-Rahman, Phys. Rev. D 45, 3497 (1992)
    • (1992) Phys. Rev. D , vol.45 , pp. 3497
  • 74
    • 0000944691 scopus 로고
    • W. Chen and Y.-S. Wu, Phys. Rev. D 41, 695 (1990).
    • (1990) Phys. Rev. D , vol.41 , pp. 695
    • Chen, W.1
  • 93
    • 0000607990 scopus 로고
    • A. I. Arbab and A.-M. M. Abdel-Rahman, Phys. Rev. D 50, 7725 (1994).
    • (1994) Phys. Rev. D , vol.50 , pp. 7725
    • Arbab, A.I.1
  • 95
    • 0003074777 scopus 로고
    • Ph. Spindel and R. Brout, Phys. Lett. B 320, 241 (1994).
    • (1994) Phys. Lett. B , vol.320 , pp. 241
    • Brout, R.1
  • 104
    • 85039012337 scopus 로고    scopus 로고
    • J. W. Moffat, Los Alamos report astro-ph/9608202(1996).
    • (1996)
    • Moffat, J.W.1
  • 110
    • 85038986932 scopus 로고    scopus 로고
    • As defined, for example, in
    • As defined, for example, in 11, p. 410. It is interesting to note that expressions of the form (3.1), in which some cosmic scalar field decays monotonically everywhere, may be essential in attaching physical significance to the concept of cosmic time. One assumes in the standard model of cosmology that four-dimensional spacetime can be foliated into a series of spacelike hypersurfaces, each a surface of simultaneity with respect to cosmic time. But the idea remains largely esoteric until these surfaces are “tagged” with successive values of some physical quantity such as proper density or black-body radiation temperature. In the theories we consider here, this role could equally well be played by successive values of the cosmological “constant.”
  • 115
    • 85039026130 scopus 로고    scopus 로고
    • W. L. Freedman, Los Alamos report astro-ph/9612024(1996).
    • (1996)
    • Freedman, W.L.1
  • 116
    • 85038977045 scopus 로고    scopus 로고
    • B. Chaboyer, Los Alamos report astro-ph/9706128(1997).
    • (1997)
    • Chaboyer, B.1
  • 119
    • 85039032050 scopus 로고    scopus 로고
    • J. M. Overduin and F. I. Cooperstock, in Proceedings of the 7th Canadian Conference on General Relativity and Relativistic Astrophysics (University of Calgary Press, Calgary, in press)
    • J. M. Overduin and F. I. Cooperstock, in Proceedings of the 7th Canadian Conference on General Relativity and Relativistic Astrophysics (University of Calgary Press, Calgary, in press).
  • 128
    • 85039021398 scopus 로고    scopus 로고
    • M. S. Turner, Los Alamos report astro-ph/9703161(1997).
    • (1997)
    • Turner, M.S.1
  • 129
    • 0002396557 scopus 로고
    • It is difficult to form more than one very faint image of a source beyond this point [J. R. Gott III, M.-G. Park, and H. M. Lee, Astrophys. J. 338, 1 (1989)].
    • (1989) Astrophys. J. , vol.338 , pp. 1
    • Gott, J.R.1    Lee, H.M.2
  • 137
    • 85039001949 scopus 로고    scopus 로고
    • B. W. Carroll and D. A. Ostlie, An Introduction to Modern Astrophysics (Addison-Wesley, Reading, MA, 1997), p. 1278
    • B. W. Carroll and D. A. Ostlie, An Introduction to Modern Astrophysics (Addison-Wesley, Reading, MA, 1997), p. 1278.
  • 138
    • 0002350632 scopus 로고    scopus 로고
    •  R. Tripp, Astron. Astrophys. 325, 871 (1997).
    • (1997) Astron. Astrophys. , vol.325 , pp. 871


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.