Introduction and Background
The galaxies that can be observed currently are represented by a variety of properties, which may include dynamics, colors, luminosity, and morphology. There are galaxies that are significantly brighter than Milky Way (Beeston et al., 2018). The multitude of types of galaxies – regular and amorphous, rotating and idle – shows that the process of evolution impacts the whole universe non-stop. With this information in mind, it is crucial to understand the basics of approaches to galaxy evolution because all this diversity indicates a specific evolutionary phase (Zhang et al., 2021). Thus, there are properties that can help us answer the question of how galaxies evolve. From the beginning, there were only radiation and matter distributed relatively homogeneously across space (Raouf et al., 2019). Thus, the transitions that astrophysicists can observe nowadays have to be seen as a result of multiple evolutionary steps that affected the global astrophysical properties of the universe (Fontanot et al., 2020). The goal of the current paper is to outline and explain the key pillars of galaxy evolution by means of addressing star formation and merging processes as evolutionary philosophies.
Results and Discussion
Star Formation as a Driver of Galaxy Evolution
This factor is exceptionally important for a more detailed understanding of galaxy evolution because the process of star formation is directly related to the ultimate luminosity increase. From the point of galaxy evolution, it means that the stellar mass of the galaxy also intensifies with time due to the existence of trends in the spectral energy distribution (Yates, Thomas and Henriques, 2017). This is the key reason why low-mass stars tend to dominate the galaxy evolution process and make galaxies redder than the massive stars that were there at the beginning when the star-forming stage began (Belfiore et al., 2019). These fundamental concepts drive the further evolution of the galaxy by altering its color, luminosity, and stellar mass. Nevertheless, the latter cannot be considered the only vital elements affecting galaxy evolution.
This is why the evolution of any given galaxy cannot be observed without paying attention to the creation of elements that are heavier than helium. These are also known as the metals that alter the post-Big Bang chemical composition of the universe (Torrey et al., 2017). Moreover, all the heavier elements that can be found on Earth or anywhere else across the universe represent the outcomes of nuclear reactions and fusions that followed the Big Bang (Mirocha, 2020). The further dispersion of chemically enriched materials can be seen as one of the key drivers of galaxy evolution (Cochrane and Best, 2018). Hence, the younger galaxies will be expected to contain more general metal content than their older counterparts.
Star Merging as a Predictor of Galaxy Fusion
Galaxy evolution can be seen as driven by star merging because the latter affects galaxy morphologies and the fundamental processes supporting star formation. According to Kraljic et al. (2018), the majority of alterations in the stellar content and volume density then affect the luminosity grade of the galaxy. Even though all cosmological epochs feature galaxy merging, it is vital to note that these processes are almost always predicted and detected based on prior evidence (Eales et al., 2018). Thus, when two or more galaxies finally merge, it may cause the resulting structure to look nothing like the original (Raouf et al., 2017). The gravitational potential of the systems has to be addressed as a means of affecting each of the galaxies involved in the synthesis.
Therefore, star merging (and galaxy merging on a larger scale) is affected by the lack of equilibrium within the system that happens to alter at least one of the resultant galaxies. The smaller cosmic objects will be destroyed or absorbed with force, causing the massive galaxy to maintain its morphology and properties (Krefting et al., 2020). The increased luminosity of the galaxy can be helpful when finding younger galaxies and observing them (Bryant, 2022). The outcomes of galaxy evolution are somewhat traumatic for the smaller galaxies because of the perturbations that the latter have to endure throughout the process (Mancuso et al., 2017). Regardless, these transformations pave the way for astrophysicists looking to uncover the fundamental stages in the evolutionary process and highlight the potential development paths for our galaxy as well.
Observing the Evolution
Astrophysicists could also tap into the area of observations in order to investigate the differences between earlier galaxies and their modern-day counterparts. Throughout the past three decades, significant technological advances have been achieved (Iyer et al., 2020). Thus, the speed of light itself contributes to the process of studying galaxy evolution during earlier cosmic epochs (Kewley, Nicholls and Sutherland, 2019). The idea is that observers can record viable data regarding the luminosity distance, look-back time, and redshift in order to understand how the evolution process happened in the past and is most likely to occur in the future (French, 2021). Star formation and merging are irreplaceable in terms of their influence on the evolutionary progression, so it is vital to expand this venue of research further (Nyland et al., 2018). Even though one cannot observe each of the peculiarities of galaxy evolution, new empirical data will have a significant impact on how we see and understand the universe.
Looking at the Bigger Picture
It is crucial to address the key evolutionary patterns revolving around galaxies in order to recognize the smaller galaxies (faint blue galaxies, for example) and how they disappeared after merging with larger galaxies. According to Kaviraj et al. (2017), many galaxies become undetectable after the star formation burst, so it is crucial to focus on spirals and ellipticals that are formed by redshift z ~ 1. The implication of all the findings from above is that the evolution of galaxies has to be observed right now, as astrophysicists now have the opportunities and instruments to be able to look at earlier epochs (Adhikari et al., 2019). It could be rather helpful for observational cosmologists to search for the antecedents of bright galaxies and record all the empirical data to add to the current knowledge regarding galaxy evolution theories and processes.
Conclusion
From the current evidence on galaxy evolution theories and key concepts, it is clear that the different paths have led the universe to giving birth tos diverse galaxies through the interface of gravity. The paradigms of star formation and merging are essential because they result from the mass distribution, mass trepidations, and the amplification of gravitational collapse affecting the future galaxy. It is important to view star formation and merging as a galaxy evolution theory because these two processes represent a thorough conceptual ground for cosmology and the evolution of the whole universe. Rigorous empirical data might be useful in this case because galaxy evolution is going to continue regardless of the external and internal factors affecting each of the cosmic objects and matters comprising the universe. Deeper insight into the respective evolutionary processes will make it much easier for astrophysicists to deploy more galaxy evolution theories.
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