Immanuel Kant, probably the greatest thinker in the Western tradition, once said eloquently, “Two things fill the mind with ever new and increasing admiration and awe, the more often and steadily we reflect upon them: the starry heavens above me and the moral law within me.” We are always wondering: where all of this (universe) come from and how us become us?
Nowadays, science has brought us two great understanding about these questions with stunning evidence.
We are so lucky that now we know the answer. Something even Newton and Archimedes did not know definitive answers. The universe started from Big Bang. And evolution by natural selection that makes our ancestors become “human.”
The ultimate questions for us as humans are five things: First, where universe (all of this) come from? Second, where life comes from? Three, what makes us human? Four, why nature behave like this and not like that? Five, what is the end of all of this?
The Origin of Universe
The answer to the first question is the universe began from the “primeval atom.” It was proposed by George Lemaitre (Belgian priest and a physicist) and Alexander Friedmann (Russian physicist) in the 1920s. Edwin Hubble, Arno Allan Penzias, and Robert Woodrow Wilson gave empirical shreds of evidence for their theory. This theory is well-known right now, dubbed the Big Bang Theory.
Background: “Primeval Atom,” or also known as “Big bang,” is a prominent theory, main candidate, and well-proven empirical answer for the ultimate question, “How did the universe begin?” The Big Bang Theory is a cosmological model of the observable universe from the earliest known periods through its subsequent large-scale evolution. The model describes how the universe expanded from an initial state of extremely high density and high temperature, in short: in a very tiny atom. For several decades, the scientific community was divided between supporters of the Big Bang and the rival steady-state model, but a wide range of empirical evidence has strongly favored the Big Bang, which is now universally accepted.
The beginning: Georges Lemaître, a Belgian Catholic priest, mathematician, astronomer, and professor of physics at the Catholic University of Louvain, first noted in 1927 that an expanding universe could be traced back in time to a single originating point, which he called the “primeval atom.” He theorized this using a mathematical model derived from Albert Einstein’s relativity theory. He did this without any empirical evidence—pure mathematical.
Source: George Lemaître (1927), Un univers homogène de masse constante et de rayon croissant, rendant compte de la vitesse radiale des nébuleuses extra-galactiques. Annales de la Société Scientifique de Bruxelles, série A, 47, 49–59)
The confirmation: Working in Hooker Telescope at Mount Wilson, Edwin Hubble observed that galaxies are moving away from the Earth at speeds proportional to their distance. In other words, the farther they are, the faster they are moving away from Earth. The velocity of the galaxies has been determined by their redshift. This fact has only one meaning: the universe must be expanding, and in reverse, the universe must have a start. This confirms Lemaitre’s theory of “primeval atom.”
Source: Edwin Hubble (1929). A Relation between Distance and Radial Velocity among Extra-Galactic Nebulae. Proceedings of the National Academy of Sciences of the United States of America, 15(3), 168–173.
The ultimate evidence: Arno Allan Penzias and Robert Woodrow Wilson accidentally found proof of the existence of “The Cosmic Microwave Background” (CMB), electromagnetic radiation which is a residue from an early stage of the universe. A sufficiently sensitive radio telescope shows a faint background noise, strongest in the microwave region of the radio spectrum. The cosmic microwave background (CMB) radiation and the cosmological redshift-distance relation are together regarded as the best available evidence for the Big Bang theory.
Source: Arno Allan Penzias and Robert Woodrow Wilson (1965). “A Measurement of Excess Antenna Temperature at 4080 Mc/s.”, The Astrophysical Journal, vol. 142, pp. 419–421
The Origin of Life on Earth: Pure Chance
The second question every human being always wonder is about the magic of life. Life is complicated and evokes astonishment. Animals are so diverse, and plants are plenty. Bacteria, fungi, viruses, and all other living are marvelous. Where this all come from? The most accepted answer right now is it all began from a primordial soup struck by accidental lightning in the early Earth billions of years ago. This situation has been simulated by Stanley Miller in his laboratory.
Stanley Lloyd Miller was an American chemist who made landmark experiments in the origin of life by demonstrating that a wide range of vital organic compounds can be synthesized by fairly simple chemical processes from inorganic substances. Then he was a Professor at the University of California at San Diego. In conducting his famous experiment, Miller was inspired by his doctoral supervisor, Harold Urey, who was an American physical chemist whose pioneering work on isotopes earned him the Nobel Prize in Chemistry in 1934 for the discovery of deuterium and professor of chemistry at the University of Chicago.
The experiments: The experiment used water (H2O), methane (CH4), ammonia (NH3), and hydrogen (H2). The chemicals were all sealed inside a sterile 5-liter bottle connected to a 500 ml bottle half-full of water. The water in the smaller bottle was heated to induce evaporation, and the water vapor was allowed to enter the larger bottle. Continuous electrical sparks were fired between the electrodes to simulate lightning in the water vapor and gaseous mixture. Then the simulated atmosphere was cooled again so that the water condensed.
Results: After a day, the solution collected at the trap had turned pink in color, and after a week of continuous operation, the solution was deep red and cloudy. The boiling bottle was then removed, and mercuric chloride was added to prevent microbial contamination. The reaction was stopped by adding barium hydroxide and sulfuric acid and evaporated to remove impurities. Using paper chromatography, Miller identified five amino acids present in the solution: glycine, α-alanine, and β-alanine were positively identified, while aspartic acid and α-aminobutyric acid were less certain.
Implication: What Stanley Miller tried to demonstrate is that “with mimicking primitive earth condition (by performing lightning), inorganic elements like water, methane, etc., transform to organic elements like amino acids.” It is an experiment that sufficiently proves that life on Earth highly probably started from “unlife” matter. This is true because (1) Atmosphere condition on early Earth is well known for scientists, (2) Amino acids are building blocks of all life known to humankind.
How can it happen? The answer is by accident or randomness. Your intuition says that it is very unlikely that the combination of “unlife elements” finally made “life elements.” It may sound strange, but think about this very carefully: If you have every day of billion years to do that experiment, in one historic day, you will get the perfect combination of “the right situation” with “the right elements,” “the right heat,” and “the right lightning” to get the “life formula.”
Source: Stanley L. Miller, (1953). A Production of Amino Acids Under Possible Primitive Earth Conditions, Science 117(3046), 528–529
The Origin of Mankind
The third question as a human being is a question about ourselves. All living things different, but the human is totally different. So far, we conclude that we are the only living beings who have awareness. We know that we are human. Cat does not know it is a cat. The dog does not become aware it is a dog. Plants and stone moreover. Where this awareness come from? When the ability to think first emerge? When this ability of meta-thinking (thinking about thinking) first developed? The answer that is most widely accepted today is when we began to perform complex social interaction between males and females 40 thousand years ago.
Background: What is man? Most scientists prefer to make the distinction between the superfamily Hominoidea, which includes humans and the apes, and the family Hominidae, which includes only humans and their extinct relatives closer than the apes. Among the hominids, the almost modern Homo sapiens appeared at least 300,000 years ago, and the anatomically modern Homo sapiens sapiens, 40,000 years ago. Owen Lovejoy argued that human beings escaped from apedom because of: (1) appearance of bipedalism, (2) regular food sharing, and (3) the more or less continuous sexual availability of males and females in a monogamous pair bond.
Human beings, inherited with enough brain development and different tooth, formed a life called humanity after social interaction between male and female evolved. This social interaction between male and female distinguishes us from others.Bipedalism–one of the turning points of being human–had to have arisen for some other reason than to free the hands for making tools or weapons.
Bipedalism, according to Owen Lovejoy (an evolutionary anthropologist, anatomist, and Professor at Kent State University Ohio), served to free the hands for carrying food back to a home base so that males could provide supplemental food for females who, encumbered with children, could not get enough for themselves and their offspring. For an early hominid female, to keep her mate coming home with food, she had to become continuously sexually attractive and receptive. Apes, by contrast, are interested in sex only when the female is in heat and do not form pair bonds. Bipedal pair bond–which would enable hominid females to have more than one dependent child at a time–must have evolved quickly since behavior patterns that lead to increased reproduction tend to be fastest-evolving. Bonding would also assure a male that his mate’s children were his, too, making it worthwhile for him to share food.
Why food sharing and bonding between female and male humans is important? 1.Gestation (time from conception to born) is 38 period (longest among apedom) and also infancy time.
2.In this gestation and infancy period, it is important for a woman to maintain a man for sharing his resources because she is very dependent due to her weak condition (during pregnancy) and focus on raising children.
3.This process form higher language, settlement/roof betterment, etc.
4.With proto family like this, live in a society (gather rather than alone) had a greater chance of survival. The society where social norm formed. All of this process made humans human.
Source: C. Owen Lovejoy (1981). The Origin of Man. Science Vol. 211, Issue 4480, pp. 341-350
The Behavior of Nature
The fourth question is what nature behaves like this and not like that. Why this phenomenon happens in this way and not vice versa? The answer is because of the interaction between energy and entropy. Nature is a perfect balance of two great powers in our universe.
What makes things happen or not happen? Water flows downhill, but not up. I can put sugar in my coffee, but if I put in too much, I can’t get it out again. I can burn a match, but I can’t unburn it. Is there some cosmic rule that determines what can happen and what can’t? Josiah Willard Gibbs, with a series of papers in Thermodynamics, answered that in nature, there is a balance between two fundamental qualities: energy and entropy. Its balance alone determines whether or not something can happen.
Certain things can happen all by themselves, but they can’t happen in the opposite direction unless they get some outside help. For example, we could make water go uphill by hauling it or pumping it up. And if we really wanted to, we could get that sugar back out of the coffee by evaporating the water and then chemically separating the sugar from the coffee solids. Unburning a match is a bit tougher, but given enough time and equipment, a small army of chemists could probably reconstruct the match out of all the ash, smoke, and gases. The point is that in each of these cases, energy from outside is needed. Left entirely to herself, Mother Nature allows many things to happen spontaneously, all by themselves. But others will never happen spontaneously.
Rule 1: Energy decreases spontaneously
In general, everything will try to decrease its energy if it can. At a waterfall, the water decreases energy by falling down into a pool. But once the water gets down to the pool, it is “energy-dead.” It can’t get back up to the top. A lot of chemical reactions will happen for a similar reason: The chemicals decrease their energy by spontaneously transforming themselves into different chemicals that have less energy. The burning match is one example. But decreasing energy is only half the story of what makes things happen.
Rule 2: Entropy increases spontaneously
The other half is increasing entropy. Entropy is just a fancy word for a disorder or randomness; the chaotic, irregular arrangement of things. In the beginning, football players are lined up in an orderly arrangement—they are not disorderly, and they, therefore, have low entropy. After the play, however, they may be scattered all over the field in a more disorderly, higher-entropy arrangement.
It’s the same for the individual particles that make up all substances: the atoms and molecules. At any given time, they can be in an orderly arrangement, in a highly disordered jumble, or in any arrangement in between. But other things (namely, energy) being equal, Nature’s inclination is that everything tends to become more and more disorderly—that is, everything will increase its entropy if it can. There can not be an increase in energy, and there can not be a natural decrease in entropy.
So the question of whether or not a happening can occur in nature spontaneously—without any interference from outside—is a question of balance between the energy and entropy rules.
(1) The waterfall? That happens because there is a big energy decrease; there’s virtually no entropy difference between the water conditions at the top and the bottom. It’s an energy-driven process.
(2) The sugar in the coffee? It dissolves because there’s a big entropy increase; sugar molecules swimming around in coffee are much more disorderly than when they were tied neatly together in the sugar crystals. There is no energy difference between the solid sugar and the dissolved sugar. (The coffee doesn’t get hotter or colder when the sugar dissolves, does it?) It’s an entropy-driven process.
(3) The burning match? Obviously, there’s a big energy decrease; the pent-up chemical energy is released as heat and light. But there is also a huge entropy increase; the smoke and gases are much more disorderly than the compact little match head was. So this reaction is doubly blessed by nature’s rules, and it occurs with great gusto the instant you provide the initiating scratch. It’s driven by both energy and entropy.
What Josiah Willard Gibbs did was to devise and write down an equation for this energy-entropy balance. It happens that if this equation comes out with a negative sign, the process in question is one that Mother Nature allows to occur spontaneously. If it comes out with a positive sign, the process is impossible. Absolutely impossible, unless human beings or something else sidesteps the rules by bringing in some energy from outside.
By using enough energy, we can always overpower nature’s entropy rule that everything tends toward disorderliness. For example, with enough effort, we could collect, atom by atom, the ten million tons of dissolved gold that are distributed throughout the Earth’s oceans, sitting there just for the taking. But it is dispersed through 324 million cubic miles (1.35 billion cubic kilometers) of the ocean in a random, incredibly high-entropy arrangement. The problem is that the energy necessary to separate and purify it would cost a lot more than the value of the gold!
Source: Josiah Willard Gibbs (1876). On the Equilibrium of Heterogeneous Substances. Transactions of the Connecticut Academy of Arts and Sciences. 3: 108–248 and Robert Wolke (1999). What Einstein Didn't Know: Scientific Answers to Everyday Questions. New York: Dover Publication
The End of Universe
The fifth question as a human being is a question about the fate of our lives and the universe. The answer is two parts: First, in the micro cosmos, after we die, we will end up as food for bacteria—all of the remaining energy that still in our body will be digested and back to mother nature. Second, in the macro cosmos, the universe will expand infinity, without any end. There is no final day for the universe.
The most widely accepted theory among cosmologists about the ultimate fate of the universe is it will expand and last forever. The fate of the universe is determined by a struggle between the momentum of expansion and the pull of gravity. The rate of expansion is found by Edwin Hubble observation, while the strength of gravity depends on the density and pressure of the matter in the universe. If the pressure of the matter is low, then the fate of the universe is governed by the density.
Arguments for Universe is finally collapse (Big Crunch):
- If the density of the universe is greater than the “critical density,” then gravity will eventually win, and the universe will collapse back on itself, the so called “Big Crunch.”
- The density of the universe also determines its geometry. If the density of the universe exceeds the critical density, then the geometry of space is closed and positively curved like the surface of a sphere.
Arguments for Universe is expanding forever:
If the density of the universe is less than the “critical density, “then the universe will expand forever.
- If the density of the universe is less than the critical density, then the geometry of space is open (infinite).
- If the density of the universe exactly equals the critical density, then the geometry of the universe is flat like a sheet of paper and infinite in extent.
- If the universe were flat, the brightest microwave background fluctuations (or “spots”) would be about one degree across. If the universe were open, the spots would be less than one degree across.
…and the winner is … : Recent measurements (c. 2001) have shown that the brightest spots are about 1 degree across. Thus the universe was known to be flat to within about 15% accuracy prior to the WMAP results. WMAP has confirmed this result with very high accuracy and precision. As of 2013, we can infer that the universe is flat with only a 0.4% margin of error. This finding suggests that the universe is: flat like a sheet of paper, infinite and expanding.
WMAP is The Wilkinson Microwave Anisotropy Probe (WMAP) is a NASA Explorer mission that launched June 2001 to make fundamental measurements of cosmology — the study of the properties of our universe as a whole. WMAP has been stunningly successful, producing our new Standard Model of Cosmology.
Source: Simone Aiola, et al. (2020). "The Atacama Cosmology Telescope: DR4 Mapand Cosmological Parameters". Department of Energy of United States and https://www.osti.gov/servlets/purl/1647059
What makes these research great? The researchers are extremely creative. They can provide powerful evidences to support their theories. Many other researchers has replicated their study. Those newer results corroborates their finding. So, their theories are getting stronger day by day.