Escaping the Beginning?
Confronting Challenges to the Universe's Origin
Reasons to Believe, 2019
p 15 Introduction: Why Worry about a Beginning?
p 15-17 Detailed story of the beginning and building of the Statue of Liberty.
p 18 The Big Question: did the universe begin, or has it existed forever? If forever, then perhaps it stands as the "uncaused cause" that ends the chain of what-caused-this questions. "Scientists could continue to investigate how things form, how long it takes, and the processes involved, but eventually they run into a sobering realization. The universe is a brute reality It has no conscious thought. It has no will. It has no personality. It knows nothing of us and has no regard for our existence."
"If the universe began to exist, then it must have a sufficient cause. Something beyond the universe must exist. Perhaps that something is physical and impersonal ... or perhaps scientists encounter another sobering option. Something nonphysical and personal created the universe for a purpose. If so, then our investigations extend beyond understanding the process to understanding this powerful being. A whole host of other questions arise: Who is this being? Why did it create the universe? Does the purpose of the universe include us? If so, does this being care about us? How would we relate to such a being?"
p19 "For centuries, the only tools to investigate the beginning of the universe (or lack thereof) were philosophical and theological. Over the past few hundred years, however, scientists have developed tools that also address this question." "They do offer us the possibility to make measurements, perform calculations, and evaluate which model provides the best explanation of all the data."
p19 "Based on my studies to date, the models that best account for all the data are those positing that the universe begins to exist. I draw this conclusion in large measure because scientists have looked for so many ways to escape a beginning, only to have the universe force them back toward models with a beginning."
p 21 Ch 1 The Case for a Beginning
p21 As an undergraduate in physics in the late 1980s, the presumption of nearly everyone that the universe had had its beginning in the Big Bang.
p22-23 In the late 19th century Maxwell discovers a problem with the Newtonian idea of absolute velocity. It works ok for adding the speed of a thrown snowball from a train so that the velocities add directly. But it doesn't work at all with a light beam shined forward from the train. These discoveries raised many questions about our understanding of the universe.
p23-24 In the early 1900s it was widely presumed that the universe was static and infinite, and if space were infinite, time must be also. In such a universe, you should be able to measure absolute velocity, but the experiments with applying Newtonian mechanics and Maxwell's electromagnetic equations had shown that this was not true. Einstein tackled the problem of developing a treatment which consistently handled both. Zweerink discusses the developments under three headings:
- Laws of Physics are Constant
- The laws of physics do not depend upon location, velocity, or motion.
- Einstein's working out of a self consistent framework with constant velocity transformation led to the ideas of special relativity.
- p25 Zweerink uses an example with a rocket which is often presented as the "pole-barn paradox".
- p26 Including gravity in the treatment led Einstein to the ideas of general relativity.
- p27 Space and Time Are Dynamic
- Einstein's general relativity equations lead to a dynamic nature of space and time
- Einstein initially put in a "cosmological constant" to reduce the equations to a static solution. The evidence soon convinced him that this was not true, and the equations naturally produced an expanding or contracting universe without this constant.
- Henrietta Leavitt's study of Cepheid Variables (~1912) showed her periodic brightness variations with periods proportional to absolute brightness.
- This gave astronomers a "standard candle" tool for measuring the distance to these stars.
- Other methods for distance measurement are used, including Type Ia supernovae.
- The additional use of the Doppler red shift from distant stars allowed them to measure the recession velocity relative to the Earth.
- This gave astronomers the distance and velocity data necessary to confirm the expanding universe.
- Edwin Hubble's careful research clarified the picture of recession velocities that were greater for more distant objects, quantified in Hubble's Law.
- p28 A Singularity Enters the Scene
- With the powerful evidence for an expanding universe cited above, the question arises about whether the universe has a beginning in time.
- Stephen Hawking and Roger Penrose published a famous paper in 1970 showing that with just a few conditions, running the universe backward in time would approach zero spatial extent and infinite density, a "singularity".
- Presumptions of the Hawking-Penrose scenario are that general relativity is valid and energy is always positive.
- With those conditions, the backward progress of the universe in time would lead to conditions where the laws of physics must break down.
- This suggests that something beyond the space, time, matter and energy of this universe must act to bring them into existence.
- If the universe follows Hawking-Penrose, the universe had some sort of beginning.
- The best continuing evidence since 1970 points toward a beginning for the universe.
p 31 Ch 2 Mapping the Landscape
p31-32 The prevailing picture of the universe is the inflationary big bang model, or synonymously the Lambda cold dark matter (ΛCDM) model. It projects back to an extremely hot dense state about 13.8 billion years ago and is projected to be 100 billion light years across.
p32 "Big bang" refers to the development of the universe from the hot dense state, and all current data fit within this model with inflation included. If the conditions that Hawking and Penrose described apply to the universe at all times, then the singularity exists and that represents the beginning of the universe. Those who doubt that the singularity applies make up much of the discussion of this book.
- p32 A major feature of the cosmological big bang model is "inflation", an incredibly rapid expansion in the earliest moments of the universe.
- Universe increased by enormous factor of 1026, a scale like growing a proton to the size of the planet Mercury.
- Alan Guth proposed the inflationary model and found that it offered solutions to problems with the big bang model.
- The temperature of the universe is incredibly uniform, within one part in 100,000, without being in causal contact.
- This is called the "horizon problem" since regions beyond each other's "horizon" to interact and come to thermal equilibrium are nevertheless at almost identical temperatures.
- Measurements of the Cosmic Microwave Background Radiation establish this remarkable uniformity of the thermal backgound of the universe.
- The geometry of the universe is remarkably close to being "flat", even though that is an unstable condition.
- This is called the "flatness problem" since the mass density of the universe is incredibly finely tuned to the critical value needed to stop the expansion at infinity. More mass and it would collapse back, with less it would never stop expanding.
- The interactions of the four fundamental forces should produce magnetic monopoles, but none were observed.
- This monopole problem is presumably met by the superfast expansion that diluted them to the point that they are unobservable.
- p33 Unified Laws. There are four fundamental forces or interactions operating in the universe.
- Gravity affects anything with mass or energy, is infinite in range and has a massless exchange particle called a graviton. It provides some uncertainty in this discussion of a beginning since there is no relativistic theory of gravity, and that is a requirement for the Hawking-Penrose theorems.
- The electromagnetic force affects anything with charge and is infinite in range with a massless exchange particle called a photon.
- The strong nuclear force holds nuclei together and has a very short range because its exchange particles have significant mass.
- The weak nuclear force takes part in many radioactive decays and has a very short range because its exchange particles have significant mass.
- While very different forces in today's universe, they are thought to have been unified into a grand unified force in the very early universe. It is thought that they separated by spontaneous symmetry breaking in the early universe.
- p34 Making the Fundamental Particles and Some Elements
- As the big bang expansion and cooling progresses, the energy conditions are met for the formation of fundamental particles and finally the simplest nuclei, hydrogen and helium.
- Today's universe has a relative abundance of about 74% hydrogen, 24% helium, 1% oxygen, and 1% of everything else.
- The rates of production can be modeled from energy considerations and agree very well with the observed abundance.
- Sufficient time and cooling produce the conditions for electrons to be collected to form whole atoms.
- At about 380,000 years, sufficient cooling allowed hydrogen and helium atoms to form. This is sometimes called the "transparency point" because electromagnetic radiation could then travel more freely through space.
- The radiation that from this time could expand through the entire universe formed the Cosmic Microwave Background Radiation, which was discovered experimentally by Penzias & Wilson in 1965. They received the Nobel Prize for that discovery in 1978.
- p35 Stars, Galaxies, and Clusters of Galaxies
- Some kind of mass non-uniformities allowed mass to begin gravitational clumping to form stars and galaxies.
- An example is the evolution of the Sun to the Main Sequence of stars.
- A sufficient amount of collapse produces high enough temperatures and pressures to initiate nuclear fusion, producing the energy to make the stars luminous.
- In addition to energy release, the nuclear fusion forms nuclei of heavier elements and contributes to nuclear synthesis in the stars.
- Nuclear synthesis in the cores of stars is mostly limited to iron and below, and the heavier elements are thought to be formed in supernovae and in neutron star mergers.
- The composition of our Sun could not have been manufactured there, and the elements above hydrogen and helium are thought to have been supplied from the distribution of elements from nearby supernovae.
- Although one would expect only a small amount of rotation in the hydrogen cloud that formed our solar system, the application of conservation of angular momentum implies that the amount of rotation would increase with the collapse and provide the rotational motion responsible for planetary orbits.
- A value for the age of the solar system can be implied from radiometric data from a vast number of meteorites, with basically date the asteroid belt.
p36 With an age of about 4.5 billion years, the solar system is about a third of the apparent age of the universe, so could have gathered heavy elements from maybe three cycles of star formation. In any case, it was able to collect the necessary elements from which life is made. Jeff places human origin at about 100,000 years. He includes a timeline of important events on pg 37. So the existence of humanity is an exceedingly tiny fraction of the apparent age of the universe.
p40 Jeff notes that the idea of the multiverse was considered as early as Isaac Newton and Erwin Schrodinger, but not widely considered until the development of inflationary cosmology in the 1990s
- p40 The Borde-Guth-Vilenkin Theorem
- While the mechanisms of inflation seem to produce a multiverse, they violate a criterion of the Hawking-Penrose theorems.
- The version of inflation developed by Guth continues forever once it gets started, not so in the real universe.
- This revised theorem applies to the multiverse and implies that even it begins to exist, or at least that new physics must exist at some past boundary.
p41 Quantum gravity remains a major limit on discussions of the beginning of the universe. We don't have a quantum theory of gravity, and need a quantum treatment to have confidence in the Hawking-Penrose theorem pointing to a beginning.
p42 "The Bible also describes a universe sustained by God's nature - one that is trustworthy, reliable, and even constant in its fundamental laws (Jeremiah 33)." Though we know much detail about the workings of the universe now "it is remarkable that a book authored thousands of years before the advent of humanity's thriving scientific enterprise even comes close to matching the extraordinary picture painted by the latest scientific results."
p 43 Ch 3 Can We Even Define Time?
p43 "Genesis 1 starts with arguably the most known verse of the Bible, 'In the beginning God created the heavens and the earth.' The next sentence (verse 2) immediately shifts the frame of reference to the surface of the Earth, after which the rest of the creation account describes a largely sequential set of events that transform Earth from a barren wasteland to one teeming with a stunning diversity of life. The phrase "and then God" repeats regularly throughout this account."
- p44 Scientific Issues with Time
- p47 Philosophical Issues with Time
- Humans are the only creatures on Earth who contemplate the workings of the universe.
- Do the past, present and future actually exist?
- The A-theory of time, or 'presentism' says that only the present exists.
- The B-theory of time contends that the passage of time is an illusion perceived by the mind.
p48-49 "On a B-theory, a beginning may be no more significant than the left edge of a ruler, except for two things: the Bible predicts one, and it is strange for an eternalist structure to mimic "beginning to exist" so closely. I find it interesting that the A-theory of time matches our experience of reality, but the B-theory of time aligns more with how Christianity describes God's view of time."
- p49-50 Causality as a foundational concept
- What happens "before" affects what happens "after", but never the reverse.
- The Bible, in contrast to the prevailing Near Eastern way of thinking about time, accurately describes this property of the universe.
- Recent advances by scientists seeking to understand how space and time form and interact provide additional support for the biblical notion that causality arises from the Creator.
- Causal dynamical triangulation (CDT) is an approach to causality in the absence of a comprehensive theory of gravity and quantum mechanics.
- A space-time structure to resemble the universe is constrained to obey quantum mechanics.
- Space-time building blocks were allowed to interact without other constraints like the number of dimensions.
- When they entered the building block of causality, then they were able to create stable, four-dimensional universes.
- If correct, the resulting "arrow of time" that allows us to distinguish the past from the future derives from something outside of space and time.
- In other words, causality would indicate that something beyond this universe encoded cause and effect into the very fabric of space-time.
- Without causality, life becomes a mechanical existence devoid of any hope, joy, or intrigue.
- Although our past influences our future, it does not dictate future events. We can choose among a number of different paths for our future.
- Though sometimes taken for granted, a universe with such features rouses wonder and gratitude.
p 53 Ch 4 How Long Ago Was the Beginning?
p53 "When did the universe come into existence?" He quotes the current result using the Planck satellite: 13.799 +/- 0.021 billion years.
p53 Starts story of our study of that question, and says "The Hubble Space Telescope launched in 1990 mainly to determine the expansion rate with enough precision to give a good age."
p54 He traced some of the history of developing values for the Hubble constant.
p54 "In order to translate the Hubble constant into an age, the mass-energy density of the universe must be known." Until the 1990s it was thought that there was only mass density. He discusses the question of whether the universe is open, closed, or flat.
p55 Astronomers measured a ratio called Ωm, the mass density of the universe divided by the mass density required for a flat universe. The inflationary model developed in the 1980s predicted a value of Ωm = 1.0 . But at that time they were aware only of ordinary mass, so they were not seeing anything close to 1.
p55 The use of the Type Ia supernovae to measure the distance to the most distant galaxies revealed an acceleration of the expansion of the universe. This made us aware of what is often called "dark energy", but Jeff calls it "space energy". This discovery led to Nobel prizes for two experimental groups. (Eric Smith worked with one of the groups.) There was also the discovery of dark matter, and the combination of it with ordinary matter and space energy came close to the critical density for a flat universe.
p55 The Hubble Space Telescope improved accuracy greatly, but there was still a conflict with globular cluster ages, which were as high as 16-18 billion years -- how could they be older than the universe?
p56 The Hipparcos satellite launched in 1989 gave better stellar parallax measurements, giving more accurate distances to the globular clusters showing that they were further away and therefore their stars were brighter than had been presumed. This brought the globular cluster ages down to around 12.5 billion years . "The problem dissolved."
p56 Jeff discusses a 2003 conference on WMAP researchers. He also mentions COBE and the fact that WMAP had 10x better resolution. That conference was pushing the age toward 13.7 billion years, and since 2003 there was 8 more years of WMAP research. Then Planck was launched in 2009 and mapped the CMB for 4 1/2 more years. All these measurements and calculations culminated in the Lambda cold dark matter (ΛCDM) concordance model.
p57 Table and pie chart. After the extensive data from the Planck satellite was received, the 2015 reports from the Planck Collaboration presented descriptive parameters for the universe in the ΛCDM concordance model:
|Normal Matter Density, Ωb||0.0486 +/- 0.0003|
|Dark Matter Density, Ωc||0.2589 +/- 0.0022|
|Space-Energy Density, ΩΛ||0.6911 +/- 0.0062|
|Curvature Ωk (0 => flat)||0.0008 +/- 0.0040|
|Hubble constant, H0||67.74 +/- 0.46 km/s/megaparsec|
|Age of the universe, Tuniv||13.799 +/- 0.0040 billion years|
|Spectral Index, ns||0.9667 +/- 0.0040|
p 63 Ch 5 How Large Is the Universe?
p 69 Ch 6 Has Our Universe Always Looked the Same?
p 77Ch 7 Did Our Universe Reincarnate?
p 87 Ch 8 Is Our Universe Part of a Vast Multiverse?
p 95 Ch 9 How Does Quantum Mechanics Produce a Multiverse?
p 103 Ch 10 Does the Multiverse Escape the Beginning?
p 109 Ch 11 Is the Universe One Big Illusion?
p 117 Ch 12 Does Quantum Mechanics Make the Answer Unknowable?
p 127 Ch 13 Dis Our Universe Come from Nothing?
p 135 Ch 14 Can't "Gravity" Create the Universe?
p 143 Ch 15 If Hawking and Kraus Are Right, Does That Remove God?
p 153 Ch 16 Who Created God?
p 163 Ch 17 Is Christianity Wrong If There Was No Beginning?