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A New Cosmological Model of the Universe and New Interpretation for the Cosmic Microwave Background and Type Ia Supernovae Redshifts

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A New Cosmological Model of the Universe and New Interpretation for the Cosmic Microwave Background and Type Ia Supernovae Redshifts A New Cosmological Model of the Universe and New Interpretation for the Cosmic Microwave Background and Type Ia Supernovae Redshifts Branislav Vlahovic North Carolina Central University, Fayetteville St. Durham, NC 27707 Abstract Presented is new cosmological model that assumes radial expansion of galaxies with a speed close to c, and confinement of the galaxies and motion of light on the sphere defined by the position of galaxies. The model predicts correct values for the Hubble constant H0 = 71.17 ± 0.86 km/s/Mpc, size of the observable universe, and speed of the event horizon. It explains why the observed cosmic microwave background is always the same, regardless of the direction in which the measurement is performed and explains uniformity of the CMB without inflation theory. Through relativistic mass correction, this model also provides an explanation for critical density without use of dark mass and dark matter. The model also explains that type Ia supernovae redshifts are not related to the accelerated expansion of the universe and dark energy. It is in agreement with type Ia data and with Hubble Ultra Deep Field (HUDF) optical and near-infrared survey performed in 2004. Introduction The distance to the edge of the observable universe is roughly the same in every direction. Therefore, the observable universe is a spherical volume centered on the observer and from our perspective it appears to be a sphere with a comoving radius of about 14 billion parsecs (about 45.6 billion light-years). It includes signals, inside particle horizon, since the beginning of the cosmological expansion (the Big Bang in traditional cosmology, the end of the inflationary epoch in modern cosmology). Although many theories require a total universe that is much larger (for instance according to the theory of cosmic inflation and its founder, Alan Guth, the lower bound for the diameter of the entire universe should be at least in the range of 1023 to 1026 times as large as the observable universe) it is also possible that the universe is smaller than the observable universe. The reasoning behind the latter case is a possibility that what we take to be very distant galaxies may actually be duplicate images of nearby galaxies, formed by light that has circumnavigated the universe. A lower bound of 24 gigaparsecs on the diameter of the whole universe is predicted in [1] (regardless the difficulties to test this hypothesis experimentally, because different images of the same galaxy might appear quite different in different eras in its history) making it, at most, only slightly smaller than the observable universe. However, let us here note that if the boundary of the visible universe (which is about 2% smaller than observable universe) approximately corresponds to the physical boundary of the universe at the present time (if such a boundary exists) it would imply that Earth is 1 exactly at the center of the universe. This is a non Copernican model which is difficult to believe. According to the Big Bang model, the radiation from the sky we measure today comes from a spherical surface called the surface of last scattering, which represents the collection of spots in space at which the decoupling event is believed to have occurred when the universe was approximately 380,000 years old and at a point in time such that the photons from that distance have just reached observers. Observing the background radiation coming from opposite directions, we are looking at the two regions billions of light years apart on opposite sides of our observable universe, but we are seeing them as they were when they were only 380,000 years old. When we are looking at the early universe, we are looking at the image of a sphere with the size of only 36 Mly. That sphere has expanded to 1292 times the size it was when the CMB photons were released; hence, the most distant matter that is observable at present, 46 billion light-years away, was only 36 million light-years away from the matter that would eventually become Earth when the microwaves we are currently receiving were emitted. The uniformity of CMB and the general sameness of the observable universe at very large scales are explained by the inflation model, which assumes that tiny region much smaller than the nucleus of an atom expanded to become entire part of the observable universe. Let us here note that inflation ended when universe was only 10-32 second old. From that time to the era of decoupling the universe went through the period of the most significant transformations, with the densities changed from 1038 kg/m3 to 10-17 kg/m3 and temperature changed from 1029 K to about 3000 K. The high degree of isotropy observed in the microwave background indicates that any density variations from one region of space to another at the time of decoupling must have been small, at most a few parts in 105 and that the temperature variations are smaller than 30-40 millionths of a Kelvin from place to place in the sky. Keeping in mind that during this period of transformation some regions of universe were separated by as much as 36 Mly and were not able to communicate for the period of 380,000 years, it is at least surprising that all of them will end with almost exactly the same density and temperature. It is also important to note that this almost perfect uniformity in CMB cannot explain formation of larger structures such as galaxies and clusters without introducing cold dark mater. We will show that there is another possible solution without inflation theory and dark matter and dark energy if a Copernican model for interpretation of the universe and CMB is applied. The proposed model Modern cosmological models are isotropic and homogenous on large scale. This means that all observers in all galaxies will find themselves to be in the “center” of expansion, with all other galaxies moving away with velocities proportional to their relative distances v = Hod. This statement means that there is no center and no preferred position. However, when this is combined with the definition of the visible universe (as comoving distance of 14 Bly in any direction from Earth) and with the interpretation of the CMB 2 (as a sphere that surrounds us, Fig. 1.), it appears to be the origin for the misconceptions incorporated in the current cosmological models. Origin of CMB Fig 1. a) visible universe and expansion of space and b) CMB as visible from the Earth. It has been always emphasized that galaxies do not move through space and that the universe is not expanding into empty space around it, for space does not exist apart from the universe. An argument for this is that, for example, Earthly occurrences must involve motions through space and that we have no such experience in our everyday lives. However, this argument is similar to the Aristotle’s argument that Earth is not moving (since if it is moving we will always experience strong wind) and can be easily refuted because, as it is well known by special relativity that we cannot measure our absolute speed. Having all that in mind, let us be for a moment open minded and devise another possible interpretation for the observable universe and also a different interpretation for the CMB, which are both as it will be shown consistent with cosmological observations and are actually more aligned with Copernicus principle. The proposed model will incorporate both motion of the galaxies through space and expansion of space. The presence of matter or energy causes warping, or curvature, of spacetime. In a high- density universe (Ω0 > 1), space is curved so much that it bends back on itself and “closes off”. It is difficult to visualize a three-dimensional volume arching back on itself in this way, but a two dimensional version is the surface of the sphere. Just for purpose of visualization, let us assume for a moment that we cannot visualize or experience in any way the third dimension perpendicular to the sphere’s surface; that we and the light rays are confined to the sphere’s surface, just as we are in reality confined to the three- dimensional volume of our universe. In this model the universe can be schematically represented by Fig. 2. In this model galaxies are expanding from the center of the universe (place of Big Bang) with the speed (as it will be shown later) close to the speed of the light. All galaxies are 3 on the surface of the sphere and, just for example, our galaxy is marked by A. As mentioned earlier, the light is confined to the surface and can only travel on the surface of the sphere; for that reason we cannot point to the center of the universe. As seen from our galaxy all other galaxies are moving away from us (and from each other) with the speed v = v0Θ, which is actually Hubble law v = H0 x distance. In this schematic, looking from the position of our galaxy, the place of decoupling (the surface of last scattering) is on the opposite side of the sphere and it is marked by B. We can see B regardless which observation direction we will choose. Taking into account that the universe is 13.7 ± 0.17 By old [2], it gives the radius of the sphere R = 13.75 ± 0.17 Bly and distance from A to B, which represents in comoving distances the size of the observable universe equal to about 43 Bly. Using v = v0Θ = H0RΘ and expressing R in Mpc, it is easy to calculate value for the Hubble’s constant H0 = 71.17 ± 0.86 km/s/Mpc, which is in the agreement with the experimental data.
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