What&#39;s the Matter with Matter?

Ron  Choong

doi:10.3847/2041-8205/828/1/L6

What's the Matter with Matter?

Ron Choong

2024, What's the Matter with Matter?

https://doi.org/10.3847/2041-8205/828/1/L6

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Abstract

A brief excursus into the nature of matter for theological reflection on the doctrine of creation

Context. In spite of the numerous studies of low-luminosity galaxies in different environments, there is still no consensus about their formation scenario. In particular, a large number of galaxies displaying extremely low surface brightnesses have been detected in recent years and the nature of these objects is still under discussion. Aims. In order to enlarge the sample of known low-surface-brightness (LSB) galaxies and to try to provide clues about their nature, we report the detection of eight such objects (µ eff,g 27 mag arcsec −2) towards the group of galaxies Pegasus I. They are located, in projection, within a radius of ∼200 kpc in the very center of Pegasus I, close to the dominant elliptical galaxies NGC 7619 and NGC 7626. Methods. We analyzed deep, high-quality GEMINI-GMOS images with ELLIPSE within IRAF in order to obtain their brightness profiles and structural parameters. We also fit Sérsic functions to these profiles in order to compare their properties with those of typical early-type galaxies. Results. Assuming that these galaxies are at the distance of Pegasus I, we have found that their sizes are intermediate among similar objects reported in the literature. In particular, we found that three of these galaxies can be classified as ultra-diffuse galaxies and a fourth one displays a nucleus. The eight new LSB galaxies show significant color dispersion around the extrapolation towards faint luminosities of the color-magnitude relation defined by typical early-type galaxies. In addition, they display values of the Sérsic index below 1 (concave brightness profiles in linear scale), in agreement with values obtained for LSB galaxies in other environments. Conclusions. We show that there seems to be a bias effect in the size distributions of the detected LSBs in different environments, in the sense that more distant groups/clusters lack small r eff objects, while large systems are not found in the Local Group and nearby environments. While there may be an actual shortage of large LSB galaxies in low-density environments like the Local Group, the non-detection of small (and faint) systems at large distances is clearly a selection effect. As an example, LSB galaxies with similar sizes to those of the satellites of Andromeda in the Local Group will be certainly missed in a visual identification at the distance of Pegasus I.

8 What’s the Matter5 with Matter? In PHYSICS, our inability to detect the bulk of matter led many to question the assumption that all matter is detectible. However, the Hubble Space Telescope (1998) stunned astronomers with the fact that the universe is expanding faster than it has ever expanded in the past. The unknown solution was called Dark Energy. Today, we postulate that the bulk of the universe is made up of unobservable 27% Dark Matter, 68% Dark Energy with just 5% normal matter, which are made up of baryons.6 Dark Energy is the force that pushes the universe further and further apart, causing its expansion while Dark Matter forms the bulk of the universe’s mass, which restricts the universe from blowing itself apart. This push and pull cosmic battle of force of energy against gravitational mass makes it possible for the universe to exist. These strange parts of the universe were accepted only after advances in technology made their undetectibilty indirectly detectible. The invention of special telescopes allowed us to detect light coming in from different parts of the electromagnetic spectrum, long wavelengths of infra-red, micro and radio waves, as well as the short wavelengths of ultraviolet, X-rays and gamma rays. The story of Dark Matter and Dark Energy goes back before the Hubble Telescope. Dark Matter was proposed in 1933 by Fritz Zwicky to explain evidence of unseen (undetectable) mass in the Coma Cluster (Abell 1656) of galaxies. It also accounts for the fact that the amount of helium in the universe is much less than expected if matter is entirely baryonic, i.e., normal observable matter that interacts with electromagnetic radiation and hence detectible by us. The conclusion was that another kind of matter exists in the universe, and this was dubbed Dark Matter (dunkle Materie). They are “Dark” because they are made up of exotic particles like MACHOs (massive compact halo objects), elementary particles called axions or WIMPs (weakly interacting massive particles), and do not emit or interact with electromagnetic radiation. In 1992 NASA’s COBE spacecraft discovered anisotropy in the cosmic microwave background, meaning that the stars in the universe are not evenly but rather directionally distributed, further suggesting the evidence of Dark Matter. On 25 August 2016, astronomers at Yale accidentally discovered that Dragonfly 44, an ultra diffuse galaxy (UDG) with the mass of the Milky Way galaxy, but with nearly no discernable stars or galactic structure, might be made almost entirely of dark matter.7 Dark Energy was proposed in 1998 to account for the curious discovery by the Hubble Space Telescope that the universe is expanding faster and faster. Some force is pushing things despite the expected gravitational force to slow down expansion as matter gets further and further away from each other. In 1998 supernova observations of accelerated expansion provided the first direct evidence for Dark Energy, which was eventually accepted by 1999. As of 2013, the LambdaCDM8 model is consistent with a series of increasingly rigorous cosmological observations, Matter is anything whose energy density scales with the inverse cube of the scale factor ‘a’, i.e., ρ ∝ a−3. Radiation by contrast, has energy density that scales as the inverse fourth power of the scale factor ‘a’, such that ρ ∝ a−4, and a cosmological constant lambda ‘Λ’, which is independent of ‘a’. 6 http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/ 7 http://iopscience.iop.org/article/10.3847/2041-8205/828/1/L6. 8 The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), associated with dark energy, and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos: the existence and structure of the cosmic microwave 5 9 including the Planck spacecraft and the Supernova Legacy Survey (SNLS). Results from the SNLS reveal that the average behavior (i.e., equation of state) of Dark Energy behaves like Einstein's cosmological constant to a precision of 10%.9 Recent results from the Hubble Space Telescope Higher-Z Team indicate that Dark Energy has been present for at least 9 billion years and during the period preceding cosmic acceleration. Today, there are at least 3 different theories to explain Dark Energy: Property of space. Albert Einstein realized that empty space is not empty, and it is possible for more space to come into existence. One version of his gravity theory that contains a cosmological constant,10 makes a second prediction: "empty space" can possess its own energy. Because this energy is a property of space itself, as more space comes into existence, more of this energy-ofspace would appear. This form of energy causes the Universe to expand faster and faster, Quintessence (the 5th element), a dynamic energy fluid that fills all of space but affects the universe’s expansion in opposition to that of energy and matter, causing the universe to expand faster and faster, and Einstein’s theory of gravitation is wrong, and a different theory is needed to explain why the universe is expanding more and more rapidly. In CHEMISTRY, water was ubiquitous and used for so many chemical reactions, but no one knew what it was made of exactly. In the 7th century BCE, Thales of Miletus declared water to be an element. In the 5th century BCE, Plato continued this assumption and named water as one of the four elements of nature. He thought water was elemental. It took 2500 years from the time of Thales before water was “discovered’ as a wet compound made up of two dry gases. This counterproductive reality stumped so many for so long. In 1800, Johan Ritter measured the amount of hydrogen and oxygen produced by the electrolysis of water, confirming the earlier work of Henry Cavendish who discovered hydrogen (inflammable air) and Antoine Lavoisier, who gave hydrogen its name – “water-former” in Greek. This was a chemical example of how our inability to detect components of air that fused to form water misled philosophers and scientists until the 19th century. background, the large-scale structure in the distribution of galaxies, the abundances of hydrogen (including deuterium), helium, and lithium and the accelerating expansion of the universe observed in the light from distant galaxies and supernovae. See P. Kroupa, B. Famaey, K.S. de Boer, J. Dabringhausen, M. Pawlowski, C.M. Boily, H. Jerjen, D. Forbes, G. Hensler, M. Metz, "Local-Group tests of dark-matter concordance cosmology. Towards a new paradigm for structure formation" Astronomy & Astrophysics. 523, 32 (2010). 9 Astier, Pierre (Supernova Legacy Survey); Guy; Regnault; Pain; Aubourg; Balam; Basa; Carlberg; Fabbro; Fouchez; Hook; Howell; Lafoux; Neill; Palanque-Delabrouille; Perrett; Pritchet; Rich; Sullivan; Taillet; Aldering; Antilogus; Arsenijevic; Balland; Baumont; Bronder; Courtois; Ellis; Filiol; et al. (2006). "The Supernova legacy survey: Measurement of ΩM, ΩΛ and W from the first-year data set". Astronomy and Astrophysics. 447: 31–48. 10 In 1917, a year after Einstein published his theory of general relativity, he created a cosmological constant to account for the surprising fact that galaxies in the universe are not crushed by gravity but statically float in space as if some hidden force was resisting gravity. At that time, no one knew that the universe was not static. However, in 1929, Edwin Hubble announced that using a type of star called a Cepheid variable as a "standard candle" to measure distances to other galaxies, observed the expansion of the universe. Einstein bemoaned that introducing lambda, his cosmological constant to account for a static universe, was the biggest blunder of his life. The knowledge that the universe is expanding led to the inference that it was once smaller, and this led to the Big Bang Model. Today, most cosmologists think that with the discovery of Dark Energy, Einstein has been vindicated. 10 In BIOLOGY, a great mystery needed to be solved during the 19th century to avoid needless deaths from infection. When Louis Pasteur first suggested that microbes seen only with the aid of microscopes were the causal agents of disease and food decay, there was great resistance, until Robert Koch laid out the foundation of germ theory in 1905. With the discovery that bacteria and viruses invade our bodies and compete with our somatic cells for resources, the image of what constitutes us took on a different starting point. Today, each human body is seen as a colony of 100 trillion cells of which 90% are non-human in nature, living in symbiotic relationship with the human cells. This was a biological example of how our inability to detect invisible life forms fed the assumption that microbes do not exist, until microscopes enhanced visual detection. From the examples above, we can see that the history of science is replete with circumstances when scientific discoveries, technological innovations and medical advances change the scale and scope of what constitutes scientific knowledge. The boundary that separates creation, nature and non-nature may be more porous than we think. So, what’s the matter with matter? The fact of the matter is, we are still learning to describe, explain and detect matter as something contrary to radiation and mostly unknown to us.11 For the Christian doctrine of creation, it matters more than ever how we think about the appearance of matter. In creation or nature. 11 Matter is anything whose energy density scales with the inverse cube of the scale factor ‘a’, such that ρ ∝ a−3. Radiation is anything whose energy density that scales as the inverse fourth power of the scale factor ‘a’, such that ρ ∝ a−4. The cosmological constant lambda ‘Λ’ is independent of ‘a’.

What's the Matter with Matter?

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