Context. The exact formation scenarios and evolutionary processes that led to the existence of the class of low surface brightness galaxies (LSBs) have not yet been understood completely. There is evidence that the lack of star formation expected to be typical of LSBs can only occur if the LSBs were formed in low-density regions. Aims. Since the environment of LSBs has been studied before only on small scales (below 2 Mpc), a study of the galaxy content in the vicinity of LSB galaxies on larger scales could add a lot to our understanding of the origin of this galaxy class. Methods. We used the spectroscopic main galaxy sample of the SDSS DR4 to investigate the environmental galaxy density of LSB galaxies compared to the galaxy density in the vicinity of high surface brightness galaxies (HSBs). To avoid the influence of evolutionary effects depending of redshift and to minimize completeness issues within the SDSS, we limited the environment studies to the local universe with a redshift of z ≤ 0.1. At first we studied the luminosity distribution of the LSB sample obtained from the SDSS within two symmetric redshift intervals (0.01 < z ≤ 0.055 and 0.055 < z ≤ 0.1). Results. It was found that the lower redshift interval is dominated by small, low-luminosity LSBs, whereas the LSB sample in the higher redshift range mainly consists of larger, more luminous LSBs. This comes from selection effects of the SDSS spectroscopic sample. The environment studies, also divided into these two redshift bins, show that both the low mass, and the more massive LSBs possess an environment with a lower galaxy density than HSBs. The differences in the galaxy density between LSBs and HSBs are significant on scales between 2 and 5 Mpc, the scales of groups and filaments. To quantify this, we have introduced for the first time the LSB-HSB Antibias. The obtained LSB-HSB Antibias parameter has a value of 10%-15%. Conclusions. From these results we conclude that LSBs formed in low-density regions of the initial universe and have drifted until now to the outer parts of the filaments and walls of the large-scale structure. Furthermore, our results, together with actual cosmological simulations, show that LSBs are caused by a mixture of nature and nurture.

We present the combined Luminosity Function of five nearby Hickson Compact Groups. We identify at the faint end the dwarf galaxy group members using the red sequence of the Color Magnitude Diagram from our deep 2.2 m WFI photometry of Hickson Compact Groups 16, 19, 30, 31 and 42. We find that the Luminosity Function of compact groups shows a bimodal distribution of bright galaxies and a dwarf galaxy population as it is known for galaxy clusters, but not for field galaxies. From measuring the field to field variance of background galaxies fulfilling the red sequence criterion coincidentally, a lower limit for the significance of the dwarf galaxy peak in the Luminosity Function was derived. With this method we determined the dwarf galaxy peak to have a significance of more than 2.6σ. Thus, compact groups can be classified as bound systems like galaxy clusters, which also accommodate two galaxy populations. Hence, it seems less unlikely that compact groups are chance configurations of individual galaxies. Our result shows that compact groups are building blocks of galaxy clusters underlining a hierarchical model of structure formation and galaxy evolution. Further we note that the existence of a significant number of satellites in bound systems like compact groups is predicted by Λ Cold Dark Matter theory.

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