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Analysis of type 1a supernovae observations out to a redshift of $z$=1.6 shows that there is good agreement between the light-curve widths and $(1+z)$ which is usually interpreted as a strong support for time dilation due to an expanding universe. This paper argues that a strong case can be made for a static universe where the supernovae light-curve-width dependence on redshift is due to selection effects. The analysis is based on the principle that it is the total energy (the fluence) and not the peak magnitude that is the best `standard candle' for type 1a supernovae. A simple model using a static cosmology provides an excellent prediction for the dependence of light curve width on redshift and the luminosity-width relationship for nearby supernovae. The width dependence arises from the assumption of constant absolute magnitude resulting in strong selection of lower luminosity supernovae at higher redshifts due to the use of an incorrect distance modulus. Using a static cosmology, curvature-cosmology, and without fitting any parameters the analysis shows that the total energy is independent of redshift and provides a Hubble constant of $63.1\pm2.5$ kms$^{-1}$ Mpc$^{-1}$. There is no indication of any deviation at large redshifts that has been ascribed to the occurrence of dark energy.
Abstract: The black body nature of the first acoustic peak of the cosmic microwave background (CMB) was tested using foreground reduced WMAP 5-year data, by producing subtraction maps between pairs of cosmological bands, viz. the Q, V, and W bands, for masked sky areas that avoid the Galactic disk. The resulting maps revealed a non black body signal that has two main properties. (a) It fluctuates on the degree scale preferentially in one half of the sky, producing an extra {\it random} noise there of amplitude $\approx$ 3.5 $\mu$K, which is $\gtrsim$ 10 $\sigma$ above the pixel noise even after beam size differences between bands are taken into account. (b) The signal exhibits large scale asymmetry in the form of a dipole ($\approx$ 3 $\mu$K) in the Q-V and Q-W maps; and (c) a quadrupole ($\approx$ 1.5 $\mu$K) in the Q-V, Q-W, and V-W maps. While (b) is due most probably to cross-band calibration residuals of the CMB COBE dipole, the amplitude of (c) is well beyond systematics of the kind, and in any case no {\it a priori} quadrupole in the CMB exists to leave behind such a residual. The axes of symmetry of (a), (b), and (c) are tilted in the same general direction w.r.t. the axes of the Galaxy. This tilt prevents the immediate `trivialization' of (a) and (c) in terms of known effects or anomalies, including and especially those of the foreground. In particular, should future attempts in demonstrating the non-cosmological origin of (a) continue to prove difficult, it would mean that degree scale departures from the acoustic model of perturbations is occurring on the last scattering surface at the 4 -- 5 % level, and moreover the behavior varies significantly from one half of the universe to another.
Abstract: We study the spatial distribution and colours of galaxies within the region covered by the cold spot in the cosmic microwave background (CMB) recently detected by the Very Small Array (VSA; Genova-Santos et al. 2005, 2008) towards the Corona Borealis supercluster (CrB-SC). The spot is in the northern part of a region with a radius ~1 degree (~5 Mpc at the redshift of CrB-SC) enclosing the clusters Abell 2056, 2065, 2059 and 2073, and where the density of galaxies, excluding the contribution from those clusters, is ~2 times higher than the mean value in typical intercluster regions of the CrB-SC. Two of such clusters (Abell 2056 and 2065) are members of the CrB-SC, while the other two are in the background. This high density intercluster region is quite inhomogeneous, being the most remarkable feature a large concentration of galaxies in a narrow filament running from Abell 2065 with a length of ~35 arcmin (~3 Mpc at the redshift of CrB-SC) in the SW-NE direction. This intercluster population of galaxies probably results from the interaction of clusters Abell 2065 and 2056. The area subtended by the VSA cold spot shows an excess of faint (21<r<22) and red (1.1<r-i<1.3) galaxies as compared with typical values within the CrB-SC intercluster regions. This overdensity of galaxies shows a radial dependence and extends out to ~15 arcmin. This could be signature of a previously unnoticed cluster in the background.
G'day SoulYou are saying that people who write against the BBT are TROLLS.
Abstract: Models for the formation and evolution of galaxies readily predict physical properties such as the star formation rates, metal enrichment histories, and, increasingly, gas and dust content of synthetic galaxies. Such predictions are frequently compared to the spectral energy distributions of observed galaxies via the stellar population synthesis (SPS) technique. Substantial uncertainties in SPS exist, and yet their relevance to the task of comparing galaxy evolution models to observations has received little attention. In the present work we begin to address this issue by investigating the importance of uncertainties in stellar evolution, the initial stellar mass function (IMF), and dust and interstellar medium (ISM) properties on the translation from models to observations. We demonstrate that these uncertainties translate into substantial uncertainties in the ultraviolet, optical, and near-infrared colors of synthetic galaxies. Aspects that carry significant uncertainties include the logarithmic slope of the IMF above 1 Msun, dust attenuation law, molecular cloud disruption timescale, clumpiness of the ISM, fraction of unobscured starlight, and treatment of advanced stages of stellar evolution including blue stragglers, the horizontal branch, and the thermally-pulsating asymptotic giant branch. The interpretation of the resulting uncertainties in the derived colors is highly non-trivial because many of the uncertainties are likely systematic, and possibly correlated with the physical properties of galaxies. We therefore urge caution when comparing models to observations.
Abstract: The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in sub-galactic sized building blocks called haloes which are subsequently assembled into galaxies. However, exactly when this assembly takes place is a matter of some debate. Here we report that the stellar masses of brightest cluster galaxies, which are the most luminous objects emitting stellar light, some 9 billion years ago are not significantly different from their stellar masses today. Brightest cluster galaxies are almost fully assembled 4-5 Gyrs after the Big Bang, having grown to more than 90% of their final stellar mass by this time. Our data conflict with the most recent galaxy formation models based on the largest simulations of dark matter halo development. These models predict protracted formation of brightest cluster galaxies over a Hubble time, with only 22% of the stellar mass assembled at the epoch probed by our sample. Our findings suggest a new picture in which brightest cluster galaxies experience an early period of rapid growth rather than prolonged hierarchical assembly.
It is possible for the galaxies to have formed in the time available- it just happened in a slightly different way than had previously been thought. So the answer to the question which forms the title of this thread is "yes it can".
The Standard explanation of the Big Bang has it that all matter came from a small point. The matter emerged and was flung (moved) outwards.No, that is completely wrong. It is a popular myth that survives because it takes too much time and effort to explain what the Big Bang really is. But it is not any kind of explosion into pre-existing space. It has no center and no edge. Instead, the Big Bang is an explosion OF space, not an explosion INTO space. Since the very beginning, all matter and galaxies remain pretty much in place in their local space except for small local motions. The reason that galaxies get farther apart is not because of motion of galaxies through space, but because more empty space is continually being created between them. The whole universe is a 3D analog of an expanding balloon surface with dimes taped to it. All the dimes (representing galaxies) are getting farther apart from all the others even though none of them is moving, and there is no center and no edge to the balloon surface.
It has been shown by Riess et al. and Perlmutter et al. that the observed redshift-magnitude relation for supernovae of type Ia, which suggests that the deceleration parameter q0 is negative, can be explained in a Friedmann model with a positive cosmological constant. We show that a quasi-steady state cosmology (QSSC) model can also fit the supernova data. Since most of the emphasis and publicity have been concentrated on explanations involving the Friedmann model, we show how a good fit can be obtained to the observations in the framework of the QSSC. Using this model, we show that absorption due to intergalactic dust may play an important role. This may explain why a few of the supernovae observed show large deviations from the curve determined by the majority of the data.
I am not against to arguments in favour alternatives to the conventional big bang from a singularity and in fact present some of them myself in the new theories area in these pages under the title of "Evolutionary cosmology" but you are not presenting coherent ideas in an understandable form and until you do I am out.
The huge amounts of Galaxies and the complexity cannot form in just 13.7 Gyrs regardless of how many ad hoc theories you present.
It seems Ophiolite that you lack any understanding of star formation and galaxy evolution.
You are wasting my time and your time with silly troll remarks.
I think you are happy with your thoughts. It seems you have not read one link that I posted. This may help your thoughts along.http://arxiv.org/abs/0904.0002
All they say is, to paraphrase, there is still a lot of uncertainty in the specifics of our observations and that makes it difficult to determine which model of galaxy formation and the like we should follow.
Abstract: In all Friedman models, the cosmological redshift is widely interpreted as a consequence of the general-relativistic phenomenon of EXPANSION OF SPACE. Other commonly believed consequences of this phenomenon are superluminal recession velocities of distant galaxies and the distance to the particle horizon greater than c*t (where t is the age of the Universe), in apparent conflict with special relativity. Here, we study a particular Friedman model: empty universe. This model exhibits both cosmological redshift, superluminal velocities and infinite distance to the horizon. However, we show that the cosmological redshift is there simply a relativistic Doppler shift. Moreover, apparently superluminal velocities and `acausal' distance to the horizon are in fact a direct consequence of special-relativistic phenomenon of time dilation, as well as of the adopted definition of distance in cosmology. There is no conflict with special relativity, whatsoever. In particular, INERTIAL recession velocities are subluminal. Since in the real Universe, sufficiently distant galaxies recede with relativistic velocities, these special-relativistic effects must be at least partly responsible for the cosmological redshift and the aforementioned `superluminalities', commonly attributed to the expansion of space. Let us finish with a question resembling a Buddhism-Zen `koan': in an empty universe, what is expanding?
Harry, we're receiving complaints about you now.We would all appreciate it if you could lay out your criticisms of the big bang theory, rather than endlessly state your opinion and link to random scientific papers.It's also been pointed out to me that you've been banned from other fora for trolling - maybe you're just very bad at communicating, but if I receive one more complaint you can add this to the list of fora you have been banned from.