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Volumn 69, Issue 2, 2004, Pages

More examples of structure formation in the Lemaître-Tolman model

Author keywords

[No Author keywords available]

Indexed keywords


EID: 1342346476     PISSN: 15507998     EISSN: 15502368     Source Type: Journal    
DOI: 10.1103/PhysRevD.69.023502     Document Type: Article
Times cited : (47)

References (38)
  • 6
    • 85039595358 scopus 로고    scopus 로고
    • A. Krasiński, Inhomogeneous Cosmological Models (Cambridge University, Cambridge, England, 1997).
    • A. Krasiński, Inhomogeneous Cosmological Models (Cambridge University, Cambridge, England, 1997).
  • 7
    • 85039602327 scopus 로고    scopus 로고
    • More correctly, the elliptic, parabolic, and hyperbolic conditions are (Formula presented) (Formula presented) and (Formula presented) respectively, as both E and M go to zero at an origin.
    • More correctly, the elliptic, parabolic, and hyperbolic conditions are (Formula presented) (Formula presented) and (Formula presented) respectively, as both E and M go to zero at an origin.
  • 8
    • 85039599520 scopus 로고    scopus 로고
    • One of the definitions of (Formula presented) used in astronomy is: The size (Formula presented) of a galaxy cluster is that radius at which the average density within (Formula presented) equals a specified multiple of the background density (Formula presented) (e.g. 200 8). With this definition, the procedure of determining (Formula presented) is different from the one presented in Eqs. (3.5)–(3.6).
    • One of the definitions of (Formula presented) used in astronomy is: The size (Formula presented) of a galaxy cluster is that radius at which the average density within (Formula presented) equals a specified multiple of the background density (Formula presented) (e.g. 200 8). With this definition, the procedure of determining (Formula presented) is different from the one presented in Eqs. (3.5)–(3.6).
  • 9
    • 85039597906 scopus 로고    scopus 로고
    • A proper matching of first and second fundamental forms would have matched masses, energies and ages, and be a comoving surface (Formula presented) If our “compensation” procedure were executed at each time, the resulting surface would not be properly matched, nor would it be comoving.
    • A proper matching of first and second fundamental forms would have matched masses, energies and ages, and be a comoving surface (Formula presented) If our “compensation” procedure were executed at each time, the resulting surface would not be properly matched, nor would it be comoving.
  • 13
    • 85039591758 scopus 로고    scopus 로고
    • Note that the relation between mass and density in the LT model, Eq. (2.3), is very different from the flat-space relation (Formula presented) We will carry over to relativity the equation (Formula presented) resulting from the Newtonian relation with the hope that it is a good approximation at low densities and for small radii from the center. However, a completely self-consistent approach would require re-interpretation of all the relevant astronomical observations against the LT model.
    • Note that the relation between mass and density in the LT model, Eq. (2.3), is very different from the flat-space relation (Formula presented) We will carry over to relativity the equation (Formula presented) resulting from the Newtonian relation with the hope that it is a good approximation at low densities and for small radii from the center. However, a completely self-consistent approach would require re-interpretation of all the relevant astronomical observations against the LT model.
  • 14
    • 85039599915 scopus 로고    scopus 로고
    • This profile is meant for large (Formula presented) only. However, all our numerical codes cover (Formula presented) so we added (Formula presented) to avoid modifying the codes.
    • This profile is meant for large (Formula presented) only. However, all our numerical codes cover (Formula presented) so we added (Formula presented) to avoid modifying the codes.
  • 15
    • 85039589598 scopus 로고    scopus 로고
    • The LT model is general enough to describe a situation where the final profile is also just a bump on a perfectly homogeneous background, but this picture does not fit well with the popular image of mass being accreted onto the initial condensation. The “bump on a smooth background” at (Formula presented) would imply that the whole infinite background adjusted its density to the central bump, which would imply propagating the density wave to an infinite distance in a finite time.
    • The LT model is general enough to describe a situation where the final profile is also just a bump on a perfectly homogeneous background, but this picture does not fit well with the popular image of mass being accreted onto the initial condensation. The “bump on a smooth background” at (Formula presented) would imply that the whole infinite background adjusted its density to the central bump, which would imply propagating the density wave to an infinite distance in a finite time.
  • 16
    • 85039591999 scopus 로고    scopus 로고
    • In this way, we also avoid a numerical difficulty: the volume that is numerically monitored must be finite. The “condensation surrounded by a rarefaction” model has the advantage that the region outside the rarefaction remains strictly Friedmannian for all time and it is enough to monitor it only at its edge. In the “bump on a smooth background” model, the velocity perturbation spreads out to infinity; only the mass density at (Formula presented) is Friedmannian outside the bump (and even this homogeneity gets destroyed by evolution, both backward and forward in time—it is only momentary).
    • In this way, we also avoid a numerical difficulty: the volume that is numerically monitored must be finite. The “condensation surrounded by a rarefaction” model has the advantage that the region outside the rarefaction remains strictly Friedmannian for all time and it is enough to monitor it only at its edge. In the “bump on a smooth background” model, the velocity perturbation spreads out to infinity; only the mass density at (Formula presented) is Friedmannian outside the bump (and even this homogeneity gets destroyed by evolution, both backward and forward in time—it is only momentary).
  • 17
    • 85039598754 scopus 로고    scopus 로고
    • T. Padmanabhan, Cosmology and Astrophysics Through Problems (Cambridge University Press, Cambridge, England, 1996).
    • T. Padmanabhan, Cosmology and Astrophysics Through Problems (Cambridge University Press, Cambridge, England, 1996).
  • 20
    • 85039591000 scopus 로고    scopus 로고
    • E.L. Wright, see http://www.astro.ucla.edu/(Formula presented)wright/ CMB-DT.html
    • E.L. Wright, see http://www.astro.ucla.edu/(Formula presented)wright/ CMB-DT.html
  • 21
    • 85039601286 scopus 로고    scopus 로고
    • W. Hu, see http://background.uchicago.edu/(Formula presented)whu/physics/ tour.html
    • W. Hu, see http://background.uchicago.edu/(Formula presented)whu/physics/ tour.html
  • 22
    • 85039597874 scopus 로고    scopus 로고
    • W. Hu, see http://background.uchicago.edu/(Formula presented)whu/araa/ node4.html
    • W. Hu, see http://background.uchicago.edu/(Formula presented)whu/araa/ node4.html
  • 24
    • 85039595893 scopus 로고    scopus 로고
    • The velocity used here is the emitting fluid velocity relative to the normals to the constant temperature surfaces.
    • The velocity used here is the emitting fluid velocity relative to the normals to the constant temperature surfaces.
  • 25
    • 85039595566 scopus 로고    scopus 로고
    • We checked whether this profile would encounter a black hole horizon (Formula presented) The mass within radius R is (Formula presented)so while the function (Formula presented) could in principle have a root, it does not have one for reasonable astronomical parameter values.
    • We checked whether this profile would encounter a black hole horizon (Formula presented) The mass within radius R is (Formula presented)so while the function (Formula presented) could in principle have a root, it does not have one for reasonable astronomical parameter values.
  • 27
    • 85039596746 scopus 로고    scopus 로고
    • See http://www.maplesoft.com
    • See http://www.maplesoft.com
  • 28
    • 85039588941 scopus 로고    scopus 로고
    • See http://www.mathworks.com
    • See http://www.mathworks.com
  • 29
    • 85039595018 scopus 로고    scopus 로고
    • These will be useful in modelling the formation of black holes.
    • These will be useful in modelling the formation of black holes.
  • 32
    • 85039603002 scopus 로고    scopus 로고
    • H. Sato, in General Relativity and Gravitation, edited by B. Bertotti, F. de Felice, and A. Pascolini (Reidel, Dordrecht, 1984), p. 289.
    • H. Sato, in General Relativity and Gravitation, edited by B. Bertotti, F. de Felice, and A. Pascolini (Reidel, Dordrecht, 1984), p. 289.
  • 34
    • 85039597708 scopus 로고    scopus 로고
    • Indeed, all physical quantities calculated are invariant under the transformation (Formula presented)const.
    • Indeed, all physical quantities calculated are invariant under the transformation (Formula presented)const.
  • 38
    • 85039593823 scopus 로고    scopus 로고
    • If we allow (Formula presented) to diverge, then we need (Formula presented) to diverge faster, and the argument is pretty much the same.
    • If we allow (Formula presented) to diverge, then we need (Formula presented) to diverge faster, and the argument is pretty much the same.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.