Spectroscopic redshift

Figure 3.5. Spectroscopic redshift versus photometric redshift for UBVRIJ data.

While the dimensionality of space-time remains largely speculative, the argument will not be pursued any further, beyond pointing out that the naive interpretation of spectroscopic redshift as a three-dimensional Doppler effect is a futile attempt to visualize four-dimensional events. By a remarkable coincidence Segal (1976) has shown that a chronometric redshift and a Planckian microwave background occur in the same projective space as the modified Godel solution and that it satisfies all the main cosmological criteria. 

The idea of spectroscopic redshifts was inferred for the first time from the equations of general relativity. Writing the curved-space line element in the from... 

Each of the many interpretations of spectroscopic redshifts can probably be developed into a unique cosmology. Since there is no scientifically reliable means of identifying the correct one, a model, which is compatible with all of the likely interpretations, should be favoured. However, in current usage the term, cosmological redshift, is used interchangeably with Doppler shift, which relates distance to rate of recession by Hubble s law. 

Abstract. 1 present K band photometry of the objects in the spectroscopic redshift survey of [CoUess et al., 1990]. The absolute K magnitudes of the objects are consistent with the no-evolution or pure luminosity evolution models. The excess f t blue galaxies seen in the B band number counts at intermediate magnitudes are a result of a low normalization, and do not dominate the population until B 25. Extreme merging or excess dwarf models are not needed. 

Various spectroscopic approaches applied to the 510 nm transition indicate an unusual environment for the redshifted lutein (Figures 7.5 and 7.7a). Interaction with the Chi a603 could force lutein 2 molecule to adopt a twisted configuration. In addition, strong interaction with a number of aromatic residues, in particular tryptophan and phenylalanine, which possess relatively large surface areas, could further promote this distortion. It is reasonable to assume that the energy required to produce this distortion comes from the forces involved in the stabilization of LHCII trimers. 

The main limitation of the previous method is the time needed to detect (and to treat) optical spectroscopic data. A possible solution to this problem is to use photometric redshifts. Using five bands observed in photometry only (for example from the B to the J band) allows robust galaxy redshift determinations... 

The near-IR spectroscopic survey by Pettini et al. (2001) confirmed a trend which had already been suspected on the basis of the optical (rest-frame UV) data alone. When the redshifts of the interstellar absorption lines, of the nebular emission lines, and of the resonantly scattered Lya emission line are compared within the same galaxy, a systematic pattern of velocity differences emerges in all LBGs observed up to now (see Figure 30). We interpret this effect as indicative of galaxy-wide outflows, presumably driven by the supernova activity associated with the star-formation episodes. Such superwinds appear to be a common characteristic of galaxies with large rates of star formation per... 

The reduction chemistry of free porphyrins and zinc or magnesium porphyrins was studied in detail using various spectroscopic techniques such as UV-Vis-NIR absorption,5,7a,i6a,b,i7 19 resonance Raman. The first reduction of porphyrins H2Por is usually fully reversible. The absorption spectra of the thus-generated porphyrin 7i-anion radicals are characterised by a loss of intensity of the Soret band (sometimes together with a slight redshift) (see Figure 4.2). Also, the Q-bands are less intense and sometimes redshifted, compared to the parent molecules and an additional (sometimes structured) band system appears around 800 The same behaviour has been reported for... 

Spectroscopic observation indicates a relationship between redshift and intergalactic distance, which, interpreted as a Doppler effect, implies a rate of recession between galaxies that depends on their mutual separation. To account for this relationship, known as Hubble s law, a metric tensor, in which the time coordinate is separated from a monotonically expanding three-dimensional Euclidean space, is assumed. 

There is no more important concept in standard cosmology than Hubble s constant, which relates spectroscopically measured redshifts in galactic light to the estimated distance of the source and its inferred rate of recession. This definition specifies a proportionality constant only for Doppler shifts. It also occurs for redshifts with a linear distance dependence due to other causes, in which case it has no connotation to an expanding universe. It is undefined for redshifts, independent of distance. 

In the past decade several projects contributed to the luminosity distance measurements and by now (i.e., as of 2009) the list includes over 200 events. Specifically with the help of the Hubble telescope 13 new Sn la were found with spectroscopically confirmed redshifts exceeding z = 1 and at present the full sample contains already 23 z > 1 objects (Riess et al. 2007). Such objects most strongly influence the value of the deceleration parameter. A combined analysis of all Sn la data yields a deceleration parameter value of —0.7 0.1 (Kowalski et al. 2008). Its negative value signals an accelerating expansion rate at distance scales comparable to the size of the Universe. 

Furthermore, comparison between theory and experiment for the equilibrium geometries of the complexes (shown for n = 1 — 3 in Fig. 5.2) and vibrational redshifts provide critical tests of theoretical potentials. Furthermore, the spectroscopic data implicitly include the effects of nonpairwise interactions, and comparison with theoretical calculations using accurate pairwise potentials permits the quantitative determination of their sign and magnitude. 

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