The Closed Universe

Noûs ◽  
1970 ◽  
Vol 4 (3) ◽  
pp. 261 ◽  
Author(s):  
John Earman
Keyword(s):  
Closed Universe

scholarly journals Specific entropy as a clock for the evolutionary quantization of the isotropic Universe

2020 ◽  
Vol 80 (10) ◽  
Author(s):  
Andrea Campolongo ◽  
Giovanni Montani
Keyword(s):  
Constant Term ◽  
Hamiltonian Operator ◽  
Closed Universe ◽  
Classical Dynamics ◽  
Cosmological Singularity ◽  
Quantum Regime ◽  
Bouncing Cosmology ◽  
Forbidden Region ◽  
The One ◽  
Quantum Mechanical Approach

AbstractIn this paper, we analyze the dynamics of an isotropic closed Universe in presence of a cosmological constant term and we compare its behavior in the standard Wheeler–DeWitt equation approach with the one when a Lagrangian fluid is considered in the spirit of the Kuchar–Brown paradigm. In particular, we compare the tunnelling of the Universe from the classically forbidden region to the allowed one, showing that considering a time evolution deeply influences the nature of the model. In fact, we show that in the presence of the Lagrangian fluid, the cosmological singularity is restored both in the classical and the quantum regime. However, in the quantum regime the singularity is probabilistically suppressed for some energy eigenvalues and in the case the latter is equal to zero one recovers the standard WDW case. Finally, we introduce a cut-off physics feature in the Minisuperspace by considering a Polymer quantum mechanical approach limiting our attention to the semi-classical dynamics mainly (the quantum treatment is inhibited by the non-local nature of the Hamiltonian operator). We show that the singularity is again removed, like in the fluid-free model, and a bouncing cosmology emerges so that the present model could mimic a cyclic cosmology.

scholarly journals Influence of the cosmological constant in closed-universe models containing matter and radiation

1970 ◽  
Vol 66 (2) ◽  
pp. 202-216 ◽  
Author(s):  
A. Agnese ◽  
M. La Camera ◽  
A. Wataghin
Keyword(s):  
Cosmological Constant ◽  
Closed Universe ◽  
Universe Models

scholarly journals Cosmological observations in a closed universe

1995 ◽  
Vol 274 (3) ◽  
pp. 793-807 ◽  
Author(s):  
G. Bjornsson ◽  
E. H. Gudmundsson
Keyword(s):  
Closed Universe ◽  
Cosmological Observations

scholarly journals QUANTUM GEOMETRODYNAMICS OF THE BIANCHI-IX MODEL IN EXTENDED PHASE SPACE

1999 ◽  
Vol 14 (28) ◽  
pp. 4473-4490 ◽  
Author(s):  
V. A. SAVCHENKO ◽  
T. P. SHESTAKOVA ◽  
G. M. VERESHKOV
Keyword(s):  
Schrödinger Equation ◽  
Schrodinger Equation ◽  
Invariant Solution ◽  
Closed Universe ◽  
Extended Phase ◽  
Probability Interpretation ◽  
Bianchi Ix ◽  
The Universe ◽  
Quantum Geometrodynamics ◽  
Standard Probability

A way of constructing mathematically correct quantum geometrodynamics of a closed universe is presented. The resulting theory appears to be gauge-noninvariant and thus consistent with the observation conditions of a closed universe, by that being considerably distinguished from the traditional Wheeler–DeWitt one. For the Bianchi-IX cosmological model it is shown that a normalizable wave function of the universe depends on time, allows the standard probability interpretation and satisfies a gauge-noninvariant dynamical Schrödinger equation. The Wheeler–DeWitt quantum geometrodynamics is represented a singular, BRST-invariant solution to the Schrödinger equation having no property of normalizability.

scholarly journals Modeling Cosmic Expansion, and Possible Inflation, as a Thermodynamic Heat Engine

2019 ◽  
Vol 74 (2) ◽  
pp. 153-162 ◽  
Author(s):  
Christopher Pilot
Keyword(s):  
Positive Curvature ◽  
Heat Engine ◽  
Initial Energy ◽  
Closed Universe ◽  
Observable Universe ◽  
Cosmic Expansion ◽  
Initial Energy Density ◽  
Inflationary Phase ◽  
Background Temperature ◽  
Traditional Sense

AbstractAssuming a closed universe with slight positive curvature, cosmic expansion can be modeled as a heat engine where we define the “system,” collectively, as those regions of space within the observable universe, which will later evolve into voids. We identify the “surroundings,” collectively, as those pockets of space that will eventually develop into matter-filled galaxies, clusters, superclusters, and filament walls. Using this model, we can find the energy needed for cosmic expansion using basic thermodynamic principles and show that cosmic expansion had as its origin a finite initial energy density, pressure, volume, and temperature. Inflation in the traditional sense, with the inflaton field, may also not be required. We also argue that homogeneities and inhomogeneities in the WMAP temperature profile are attributable to quantum mechanical fluctuations about a fixed background temperature in the initial isothermal expansion phase of the cycle, which we identify with inflation. Fluctuations in temperature can cause certain regions of space to lose heat while other regions will absorb that heat. The voids, being those regions that absorb the heat, will expand, thereby leaving slightly cooler temperatures for the surroundings, where matter will later congregate. Upon freeze-out, this could produce the observed WMAP signature with its associated inhomogeneity. Finally, using the uncertainty relation, we estimate that the temperature and time for formation of WMAP inhomogeneities occurred at roughly 3.02 × 1027 K and 2.54 × 10−35 s, respectively, after first initiation of volume expansion. This is in line with current estimates for the end of the inflationary epoch. The heat input in the inflationary phase is calculated as roughly Q = 1.81 × 1094 J (photons only); the collective void volume increases by a factor of only 5.65. The bubble voids in the observable universe increase in size from about 0.046 to 0.262 m3 within this inflationary period in our model.

Large scale anisotropies and polarization of the microwave background radiation in homogeneous cosmologies

1984 ◽  
Vol 392 (1803) ◽  
pp. 391-413 ◽  
Keyword(s):  
Large Scale ◽  
Background Radiation ◽  
Twist Angle ◽  
Critical Density ◽  
Thomson Scattering ◽  
Degree Of Polarization ◽  
Closed Universe ◽  
Spatial Curvature ◽  
Microwave Background ◽  
Microwave Background Radiation

The polarization and anisotropy of the cosmological microwave background radiation on large angular scales are discussed. A quadrupole anisotropy in the expansion of the universe (shear) is considered in realistic cosmological models and the resulting anisotropies and polarization of the radiation are calculated. The role of spatial curvature is considered separately, and it is found to have two profound effects: first, in closed models only, the direction of polarization of the radiation will appear at observation to be twisted relative to the anisotropy; the existence of this twist implies that the closed universe has a handedness property. Second, in open models a quadrupole anisotropy may be distorted by the spatial curvature so that it resembles a dipole; in the extreme case all the aniso­tropy is confined to a region of small angular diameter (a ‘spot’). Following previous work by Dautcourt and Rose, a transfer equation for polarized radiation in a general curved space-time is derived. The effect of Thomson scattering by free electrons is included, and the equation is separated into those for the multipoles up to quadrupole by expanding in polynomials formed from spin-weighted spherical harmonics. A numerical integration of the equations is described, and the results are presented for the twist angle, the dipole and quadrupole anisotropies, the degree of polarization in the quadrupole mode and the ratio of polarization to quadrupole aniso­tropy in all models considered. The twist of polarization in closed models is large and should be easily observable if the polarization could be. This result suggests an important observational test of the spatial curvature of the standard models. The dipole produced in open models, due to distortion by the spatial curvature, is prominent; it appears unlikely that an intrinsic dipole to quadrupole ratio of less than unity arises in any open models in which the effect occurs when the density is below one-half the critical density. Finally, the ratio of polarization to anisotropy is expected to be a good indicator of the presence of shear, and is sensitive to the ionization history of the matter.

Open Systems and Consciousness: A Philosophical Discussion

2002 ◽  
Vol 09 (02) ◽  
pp. 125-151 ◽  
Author(s):  
Roman S. Ingarden
Keyword(s):  
Open Systems ◽  
Physical World ◽  
Social Software ◽  
Closed Universe ◽  
Philosophical Discussion ◽  
External Energy ◽  
The World ◽  
Conscious Thinking ◽  
The Individual ◽  
Logical Types

The proposition of the author is that sentences about sentences (meta-sentences or sentences of the 2nd order) about physical phenomena are examples of conscious thinking, i.e. the elements of consciousness. The argument is that psychical phenomena (acts of thinking or imagination) are phenomena of the second logical type: phenomena of phenomena. In other words, the individual psychical world (the world of individual consciousness) is described by a meta-theory of physics (meta-physics), while the social world (the world of social culture) can be described by a meta-meta-physics, i.e., by doubled-type description by means of sentences two logical types higher than those of the physical world. The objects in the physical world (particles, bodies, animals, persons, etc.) are defined as open systems, relatively isolated in a hypothetical physical closed universe, i.e., open systems having internal and external energy of interaction. The role of subconscious activity of the brain is also considered and explained, as well as the importance of genes and hormones for an emotional proto-language in animals and humans, and of the human language as a social software being the base for proper human consciousness. The aspect of open systems is here only slightly touched. It will be discussed in more details elsewhere.

The Spatially Closed Universe

2019 ◽  
Vol 40 (4) ◽  
pp. 353-381
Author(s):  
Chan-Gyung Park
Keyword(s):  
Closed Universe
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