Quotes & Sayings


We, and creation itself, actualize the possibilities of the God who sustains the world, towards becoming in the world in a fuller, more deeper way. - R.E. Slater

There is urgency in coming to see the world as a web of interrelated processes of which we are integral parts, so that all of our choices and actions have [consequential effects upon] the world around us. - Process Metaphysician Alfred North Whitehead

Kurt Gödel's Incompleteness Theorem says (i) all closed systems are unprovable within themselves and, that (ii) all open systems are rightly understood as incomplete. - R.E. Slater

The most true thing about you is what God has said to you in Christ, "You are My Beloved." - Tripp Fuller

The God among us is the God who refuses to be God without us, so great is God's Love. - Tripp Fuller

According to some Christian outlooks we were made for another world. Perhaps, rather, we were made for this world to recreate, reclaim, redeem, and renew unto God's future aspiration by the power of His Spirit. - R.E. Slater

Our eschatological ethos is to love. To stand with those who are oppressed. To stand against those who are oppressing. It is that simple. Love is our only calling and Christian Hope. - R.E. Slater

Secularization theory has been massively falsified. We don't live in an age of secularity. We live in an age of explosive, pervasive religiosity... an age of religious pluralism. - Peter L. Berger

Exploring the edge of life and faith in a post-everything world. - Todd Littleton

I don't need another reason to believe, your love is all around for me to see. – Anon

Thou art our need; and in giving us more of thyself thou givest us all. - Khalil Gibran, Prayer XXIII

Be careful what you pretend to be. You become what you pretend to be. - Kurt Vonnegut

Religious beliefs, far from being primary, are often shaped and adjusted by our social goals. - Jim Forest

We become who we are by what we believe and can justify. - R.E. Slater

People, even more than things, need to be restored, renewed, revived, reclaimed, and redeemed; never throw out anyone. – Anon

Certainly, God's love has made fools of us all. - R.E. Slater

An apocalyptic Christian faith doesn't wait for Jesus to come, but for Jesus to become in our midst. - R.E. Slater

Christian belief in God begins with the cross and resurrection of Jesus, not with rational apologetics. - Eberhard Jüngel, Jürgen Moltmann

Our knowledge of God is through the 'I-Thou' encounter, not in finding God at the end of a syllogism or argument. There is a grave danger in any Christian treatment of God as an object. The God of Jesus Christ and Scripture is irreducibly subject and never made as an object, a force, a power, or a principle that can be manipulated. - Emil Brunner

“Ehyeh Asher Ehyeh” means "I will be that who I have yet to become." - God (Ex 3.14) or, conversely, “I AM who I AM Becoming.”

Our job is to love others without stopping to inquire whether or not they are worthy. - Thomas Merton

The church is God's world-changing social experiment of bringing unlikes and differents to the Eucharist/Communion table to share life with one another as a new kind of family. When this happens, we show to the world what love, justice, peace, reconciliation, and life together is designed by God to be. The church is God's show-and-tell for the world to see how God wants us to live as a blended, global, polypluralistic family united with one will, by one Lord, and baptized by one Spirit. – Anon

The cross that is planted at the heart of the history of the world cannot be uprooted. - Jacques Ellul

The Unity in whose loving presence the universe unfolds is inside each person as a call to welcome the stranger, protect animals and the earth, respect the dignity of each person, think new thoughts, and help bring about ecological civilizations. - John Cobb & Farhan A. Shah

If you board the wrong train it is of no use running along the corridors of the train in the other direction. - Dietrich Bonhoeffer

God's justice is restorative rather than punitive; His discipline is merciful rather than punishing; His power is made perfect in weakness; and His grace is sufficient for all. – Anon

Our little [biblical] systems have their day; they have their day and cease to be. They are but broken lights of Thee, and Thou, O God art more than they. - Alfred Lord Tennyson

We can’t control God; God is uncontrollable. God can’t control us; God’s love is uncontrolling! - Thomas Jay Oord

Life in perspective but always in process... as we are relational beings in process to one another, so life events are in process in relation to each event... as God is to Self, is to world, is to us... like Father, like sons and daughters, like events... life in process yet always in perspective. - R.E. Slater

To promote societal transition to sustainable ways of living and a global society founded on a shared ethical framework which includes respect and care for the community of life, ecological integrity, universal human rights, respect for diversity, economic justice, democracy, and a culture of peace. - The Earth Charter Mission Statement

Christian humanism is the belief that human freedom, individual conscience, and unencumbered rational inquiry are compatible with the practice of Christianity or even intrinsic in its doctrine. It represents a philosophical union of Christian faith and classical humanist principles. - Scott Postma

It is never wise to have a self-appointed religious institution determine a nation's moral code. The opportunities for moral compromise and failure are high; the moral codes and creeds assuredly racist, discriminatory, or subjectively and religiously defined; and the pronouncement of inhumanitarian political objectives quite predictable. - R.E. Slater

God's love must both center and define the Christian faith and all religious or human faiths seeking human and ecological balance in worlds of subtraction, harm, tragedy, and evil. - R.E. Slater

In Whitehead’s process ontology, we can think of the experiential ground of reality as an eternal pulse whereby what is objectively public in one moment becomes subjectively prehended in the next, and whereby the subject that emerges from its feelings then perishes into public expression as an object (or “superject”) aiming for novelty. There is a rhythm of Being between object and subject, not an ontological division. This rhythm powers the creative growth of the universe from one occasion of experience to the next. This is the Whiteheadian mantra: “The many become one and are increased by one.” - Matthew Segall

Without Love there is no Truth. And True Truth is always Loving. There is no dichotomy between these terms but only seamless integration. This is the premier centering focus of a Processual Theology of Love. - R.E. Slater

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Note: Generally I do not respond to commentary. I may read the comments but wish to reserve my time to write (or write off the comments I read). Instead, I'd like to see our community help one another and in the helping encourage and exhort each of us towards Christian love in Christ Jesus our Lord and Savior. - re slater

Tuesday, February 8, 2022

Index - Process Science & Cosmology



Index to Process Science & Cosmology

Here, I have mixed in a little bit of everything over the past two years (2020 - Feb 2022) related to quantum cosmologies as I have covered them in some aspect of the subject itself - along with any topics especially relating to cosmology and metaphysics, process philosophy and theology, or the evolutionary origins of the universe from a processual basis.

The reader may pick-and-choose the topics to connect together one-with-the-other with the thought that hopefully, I've been able to address a few other topics which may help "expand and extend" the cosmic metaphors, philosophies, and ontological possibilities humanity has been searching; topics which may help make sense of the cold, hard scientific facts the metamodern sciences are discovering one-after-the-other. If you will then, this index here is a constructive cosmological process-based metaframework of the living organism we live within panrelationally, panexperientially, and panpsychically.

As you'll see, my bias will run towards Whitehead's Philosophy of Organism ( sic, Process Philosophy) as it has been responding to the quantum sciences of the 20th and 21st Centuries. As an integral philosophy of everything, process thought has been responding quite helpfully in providing the (processual) sciences of cosmology and evolution with a metaphysical and ontological perspective (this latter, re ontology, comes courtesy of process theology).

You'll also notice from the CD cover below, that science itself has been attempting to provide it's own philosophical perspectives through "look-backs" in history. For the English mathematician and philosopher Alfred North Whitehead, he started with the German Idealist Hegel whose cosmological outlook began - but became overwhelmed - within the trappings of his enlightenment era when fellow philosophers over the next several hundred years got caught up in the idea of a mechanistic, matter v mind cosmology and did not extend his work.

As a Scientist and Royal Academy Fellow, Whitehead noticed the need for a relevant cosmology after completing his Principia Mathematic with Bertrand Russel and immediately set out to complete his life's last project by re-orienting science towards a relationally processual essence of being. Translated, this meant to see the world as "an organic essence full of relationality, open-endedness, and prehensive concreasences of actualities and possibilities."

And so I don't think the reader will be disappointed when reading through these postings. For myself, Process Philosophy has meaningfully circumscribed itself around all previous Western and Continental philosophies, and has helpfully integrated some of the more salient points of Middle-Eastern and Oriental philosophy as well. This is why Process Philosophy portends towards becoming, for the time being, an overarching integral theory of cosmology, metaphysics, and ontology.

See what you think. Enjoy.

R.E. Slater
February 8, 2022





EVERYTHING FROM 2021-2022
RELATING TO PROCESS COSMOLOGY
(in chronological order)


You will find that there will be some overlap of the same articles appearing in several categories. As explanation, I felt these posts aptly fit each categorical reference which it subtended under. Hence, the topic at hand was broad enough to be applied widely so that if a researcher wished to study a topical category of choice this form of categorization may help the best in attaining to their effort. Thus the overlaps. (PS. Similarly, you'll find a dizzying amount of article replications in the "Index - Bible topics" as well; again, because of the breadth of topic being handled by that one specific post.) With deepest apologies.
- R.E. Slater


Process Cosmology
Science & Cosmology
Science & the Universe


Please note: All articles are listed chronologically by date, each building upon the last. Though the reader may pick and chose their subject as they please, do realize that for myself I wrote some of these in a "date-ordered series" attempting to connect my separate thoughts to the last as I understood them. Hence, what wasn't covered in one article was most probably covered by several other past articles or future articles which I had laid aside to attend to the present matter. Thus, such topics were skipped over. As example, I've spoken many times of divine immanence but have never separated out the present-ness of divine immanence. It was always assumed by myself that a present context was implied by the topic. In hindsight I will need to develop several future articles connecting these two ideas to the larger idea of process panentheism to help "round out" the subtending ideas within panentheism.
- R.E. Slater


The Collected Papers of Process Philosopher & Theologian Andrew M. Davis


Andrew M. Davis - 10 Ideas in Whiteheadian Thought



Index - Process Essays by R.E. Slater





Astrobiology, Exo-Philosophy and Cosmic Religion





Time & the Primordial Universe - Einstein vs. Bergson, by Campo & Gozzano


COSMOLOGY - The Philosophy of MetaPhysical Cosmology













































Science & Space


























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COSMOLOGY - Do We Live in a Holographic Matrix?





DO WE LIVE IN A MATRIX?
HOLOGRAPHIC UNIVERSE THEORY


HOLOGRAPHIC UNIVERSE

It could be thought of as rather like watching a 3D film in a cinema. We see the pictures as having height, width and crucially, depth – when in fact it all originates from a flat 2D screen. The difference, in our 3D universe, is that we can touch objects and the ‘projection’ is ‘real’ from our perspective.

The holographic principle is a property of quantum gravity theories which resolves the black hole information paradox within string theory.

It was first proposed by Gerard 't Hooft and later a precise string-theory interpretation was given by Leonard Susskind.

The theory suggests that the entire universe can be seen as a two-dimensional information structure "painted" on the cosmological horizon, so that the three dimensions we observe are only an effective description at low energies.




The theory that reality, as we consciously experience it, is not real, goes back to the indigenous people who believed that we exist in a dream or illusion. In our current timeline, we refer to the our virtual reality experience as a matrix, grids, simulation and hologram. There are scientists who trying to prove the hologram exists and others who are trying to break us out of it. Theories about reality being a simulation are increasing.

SO DO WE LIVE IN A MATRIX?




I think that "time" is an illusion, therefore so is everything else. The universe is a consciousness hologram. Reality is projected illusion within the hologram. Our hologram is composed of grids created by a source consciousness brought into awareness by electromagnetic energy at the physical level. The hologram is created and linked through a web, or grid matrixes based on the patterns of Sacred Geometry. The hologram had a beginning and it has an end, as consciousness evolves in the alchemy of time. As the grids collapse, everything within the hologram will end as it Fades to Black.

In recent decades, advances in telescopes and sensing equipment have allowed scientists to detect a vast amount of data hidden in the ‘white noise’ or microwaves (partly responsible for the random black and white dots you see on an un-tuned TV) left over from the moment the universe was created. Using this information, scientists are able to make complex comparisons between networks of features in the data and quantum field theory. They found that some of the simplest quantum field theories could explain nearly all cosmological observations of the early universe.




Also the Professor Skenderis says:

“Holography is a huge leap forward in the way we think about the structure and creation of the universe. Einstein’s theory of general relativity explains almost everything large scale in the universe very well, but starts to unravel when examining its origins and mechanisms at quantum level. Scientists have been working for decades to combine Einstein’s theory of gravity and quantum theory. Some believe the concept of a holographic universe has the potential to reconcile the two.”

And there is a good book on The Holographic Universe if you want to rea by Michael Talbot. This is my favorite book on holographic universe.
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COSMOLOGY - How the Universe Got It's Structure


The universe’s first structure originated when some of the material flung outward by the Big Bang overcame its trajectory and collapsed on itself, forming clumps. A team of Carnegie researchers showed that denser clumps of matter grew faster, and less-dense clumps grew more slowly. The group’s data revealed the distribution of density in the universe over the last 9 billion years. (On the illustration, violet represents low-density regions and red represents high-density regions.) Working backward in time, their findings reveal the density fluctuations (far right, in purple and blue) that created the universe’s earliest structure. This aligns with what we know about the ancient universe from the afterglow of the Big Bang, called the Cosmic Microwave Background (far right in yellow and green). The researchers achieved their results by surveying the distances and masses of nearly 100,000 galaxies, going back to a time when the universe was only 4.5 billion years old. About 35,000 of the galaxies studied by the Carnegie-Spitzer-IMACS Redshift Survey are represented here as small spheres. Credit: The illustration is courtesy of Daniel Kelson. CMB data is based on observations obtained with Planck, an ESA science mission with instruments and contributions directly funded by ESA Member States, NASA, and Canada.


Pillar of Cosmology: ‘Elegant’ Solution Reveals
How the Universe Got Its Structure

By CARNEGIE INSTITUTION FOR SCIENCE
April 28, 2020


A direct, observation-based test of one of the pillars of cosmology.

The universe is full of billions of galaxies — but their distribution across space is far from uniform. Why do we see so much structure in the universe today and how did it all form and grow?

A 10-year survey of tens of thousands of galaxies made using the Magellan Baade Telescope at Carnegie’s Las Campanas Observatory in Chile provided a new approach to answering this fundamental mystery. The results, led by Carnegie’s Daniel Kelson, are published in Monthly Notices of the Royal Astronomical Society.

“How do you describe the indescribable?” asks Kelson. “By taking an entirely new approach to the problem.”

“Our tactic provides new — and intuitive — insights into how gravity drove the growth of structure from the universe’s earliest times,” said co-author Andrew Benson. “This is a direct, observation-based test of one of the pillars of cosmology.”

The Magellan telescopes at Carnegie’s Las Campanas Observatory in Chile, which were crucial to the ability to conduct this survey. Credit: Photograph by Yuri Beletsky, courtesy of the Carnegie Institution for Science

The Carnegie-Spitzer-IMACS Redshift Survey was designed to study the relationship between galaxy growth and the surrounding environment over the last 9 billion years, when modern galaxies’ appearances were defined.

The first galaxies were formed a few hundred million years after the Big Bang, which started the universe as a hot, murky soup of extremely energetic particles. As this material expanded outward from the initial explosion, it cooled, and the particles coalesced into neutral hydrogen gas. Some patches were denser than others and, eventually, their gravity overcame the universe’s outward trajectory and the material collapsed inward, forming the first clumps of structure in the cosmos.

The density differences that allowed for structures both large and small to form in some places and not in others have been a longstanding topic of fascination. But until now, astronomers’ abilities to model how structure grew in the universe over the last 13 billion years faced mathematical limitations.

“The gravitational interactions occurring between all the particles in the universe are too complex to explain with simple mathematics,” Benson said.

So, astronomers either used mathematical approximations — which compromised the accuracy of their models — or large computer simulations that numerically model all the interactions between galaxies, but not all the interactions occurring between all of the particles, which was considered too complicated.

“A key goal of our survey was to count up the mass present in stars found in an enormous selection of distant galaxies and then use this information to formulate a new approach to understanding how structure formed in the universe,” Kelson explained.

The research team — which also included Carnegie’s Louis Abramson, Shannon Patel, Stephen Shectman, Alan Dressler, Patrick McCarthy, and John S. Mulchaey, as well as Rik Williams, now of Uber Technologies — demonstrated for the first time that the growth of individual proto-structures can be calculated and then averaged over all of space.

Doing this revealed that denser clumps grew faster, and less-dense clumps grew more slowly.

And it’s just so simple, with a real elegance to it.” — Daniel Kelson

They were then able to work backward and determine the original distributions and growth rates of the fluctuations in density, which would eventually become the large-scale structures that determined the distributions of galaxies we see today.

In essence, their work provided a simple, yet accurate, description of why and how density fluctuations grow the way they do in the real universe, as well as in the computational-based work that underpins our understanding of the universe’s infancy.

“And it’s just so simple, with a real elegance to it,” added Kelson.

The findings would not have been possible without the allocation of an extraordinary number of observing nights at Las Campanas.

“Many institutions wouldn’t have had the capacity to take on a project of this scope on their own,” said Observatories Director John Mulchaey. “But thanks to our Magellan Telescopes, we were able to execute this survey and create this novel approach to answering a classic question.”

“While there’s no doubt that this project required the resources of an institution like Carnegie, our work also could not have happened without the tremendous number of additional infrared images that we were able to obtain at Kit Peak and Cerro Tololo, which are both part of the NSF’s National Optical-Infrared Astronomy Research Laboratory,” Kelson added.







NASA probe to make all-sky infrared map, Adam Mann, Science, 2019

News Feature: Reionizing the universe, Adam Mann, Proc Natl Acad Sci U S A, 2015






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COSMOLOGY - CMB Cold Spot Explained


When displayed on a celestial sphere, the CMB cold spot can be seen to correspond with the Eridanus supervoid, but the full extent and depth of the void is only just beginning to be quantified today. It’s plausible that the reason this spot is so cold is due to the gravitational influence of the shrinking supervoid over time. (Credit: Piquito veloz/Celestia)

KEY TAKEAWAYS

On the largest scales, the Universe is supposed to be isotropic and homogeneous: the same everywhere and in all directions.

Because the Universe has tiny, 1-part-in-30,000 imperfections imprinted on it, we expect to see a pattern of cold-and-hot spots in the leftover radiation from the Big Bang: the Cosmic Microwave Background.

But one spot in the Universe, called the "CMB cold spot," is an anomaly that we couldn't explain. At last, it's all fallen into place.


OUR UNIVERSE IS NORMAL!
Its biggest anomaly, the CMB cold spot,
is now explained

The Universe is supposed to be the same
everywhere and in all directions.
So what's that giant "cold spot" doing out there?

February 1, 2022


Since the discovery of the Cosmic Microwave Background (CMB) nearly 60 years ago, scientists have been searching for a hint — any hint — of a crack in the façade of the hot Big Bang. At every step along the way, as our instruments became more sensitive and our observational reach extended farther than ever before, the Big Bang’s predictions were borne out in spectacular fashion, one after another.

The Universe’s expansion and how that expansion changed over time was measured, and found to be precisely consistent with the expanding Universe predicted by physical cosmology. The spectrum of the CMB was measured, confirming it was the most perfect blackbody ever seen in the Universe. The initial cosmic abundances of the light elements and their isotopes were determined, and found to be in direct agreement with the predictions of Big Bang nucleosynthesis. And the formation of large-scale structure and the growth of the cosmic web matched the Big Bang’s predictions without exception.

But with the launches of WMAP and Planck, the small-scale imperfections in the CMB were measured, and one anomaly stood out: a cold spot that simply couldn’t be explained based on the Universe we knew. At last, that mystery may finally be solved, as the culprit has been identified at long last: the largest supervoid in the nearby Universe. If this research holds up, it teaches us that our Universe is normal, after all, and that the CMB cold spot isn’t an anomaly at all.

The initial fluctuations that were imprinted on our observable universe during inflation may only come into play at the ~0.003% level, but those tiny imperfections lead to the temperature and density fluctuations that appear in the cosmic microwave background and that seed the large-scale structure that exists today. Measuring the CMB at a variety of cosmic locations would be the only feasible way to disentangle the intrinsic dipole of the CMB from that induced by our motion through the Universe. (Credit: Chris Blake and Sam Moorfield)

The fact that the CMB is so perfect is, itself, a modern wonder of the Universe. Everywhere we look, in all directions, it’s plain to see just how different the Universe is from place to place. Some regions of space are extremely rich in structure, with scores, hundreds, or even thousands of large galaxies all collected into the same gravitationally bound structure. Other locations have galaxies, but they’re relatively sparsely located in small groupings and collections scattered about through space. Still other places have only isolated galaxies. In the least dense locations, there are no galaxies to be found at all for volumes that span tens or even hundreds of millions of light-years on a side.

And yet, the theory of the Big Bang comes along with an inextricable prediction: that in the earliest stages of the hot Big Bang, the Universe must have been both isotropic, or the same in all directions, and homogeneous, or the same in all locations, to a tremendous degree of precision. It can only come into existence with tiny, minuscule imperfections, or regions of slightly greater-or-lesser density than average. It’s only because of the tremendous amount of cosmic time that passes — and the relentlessly attractive nature of the gravitational force — that we have a rich, structure-filled Universe today.

The formation of cosmic structure, on both large scales and small scales, is highly dependent on how dark matter and normal matter interact. The distributions of normal matter (at left) and dark matter (at right) can affect one another, as things like star formation and feedback can affect the normal matter, which in turn exerts gravitational effects on the dark matter. The seed overdense and underdense fluctuations allowed this cosmic web of structure to arise. (Credit: Illustris Collaboraiton/Illustris Simulation)

The Cosmic Microwave Background was discovered back in the mid-1960s, and the early goals were to:

  • measure the amount of radiation emitted at different frequencies,
  • measure the peak of its temperature,
  • determine whether it was truly a perfect blackbody, as predicted, or whether it was better approximated as the sum of a series of blackbodies (which is a property of starlight),
  • to figure out the nature of the interfering emission from our galaxy,
  • and to test whether it truly had the same properties everywhere and in all directions.

Over time, we were able to refine our measurements. Initially, the CMB was announced to be at 3.5 K, which then was revised to 3 K, then 2.7 K, and a little later, a third significant figure was added: 2.73 K. In the mid-to-late 1970s, a small, 1-part-in-800 imperfection was discovered: an artifact of our own motion through the Universe.

It wasn’t until the 1990s that the first primordial imperfections were found, coming in at about the 1-part-in-30,000 level. At last, we had the observational evidence to not only confirm a Big Bang-consistent origin for the CMB, but to measure what sort of imperfections the Universe itself began with.

COBE, the first CMB satellite, measured fluctuations to scales of 7º only. WMAP was able to measure resolutions down to 0.3° in five different frequency bands, with Planck measuring all the way down to just 5 arcminutes (0.07°) in nine different frequency bands in total. All of these space-based observatories detected the Cosmic Microwave Background, confirming it was not an atmospheric phenomenon, and that it had a cosmic origin. (Credit: NASA/COBE/DMR; NASA/WMAP science team; ESA and the Planck collaboration)

You see, the hot Big Bang, although it was the beginning of our observable Universe as we know it, wasn’t the very beginning of everything. There’s a theory that’s been around since the early 1980s — cosmic inflation — that posits a set of properties that the Universe possessed prior to the start of the hot Big Bang. According to inflation:

  • the Universe wasn’t filled with matter or radiation, but a new form of energy inherent to the fabric of space itself,
  • that energy caused the Universe to expand at a rapid and relentless pace,
  • stretching a region of space no larger than the Planck length to greater than the scale of the observable Universe something like every ~10-32 seconds,
  • and then inflation ends, dumping that energy-inherent-to-space into particles (and antiparticles) for the first time, triggering the hot, dense, uniform, but rapidly-expanding conditions we identify with the hot Big Bang.

The only reason the Universe isn’t perfectly, absolutely uniform everywhere is because the tiny fluctuations inherent to quantum physics, during this epoch of rapid expansion, can get stretched across the Universe, creating the overdense and underdense seeds of structure. From these initial seed fluctuations, the entire large-scale structure of the Universe can arise.

The cold spots (shown in blue) in the CMB are not inherently colder, but rather represent regions where there is a greater gravitational pull due to a greater density of matter, while the hot spots (in red) are only hotter because the radiation in that region lives in a shallower gravitational well. Over time, the overdense regions will be much more likely to grow into stars, galaxies and clusters, while the underdense regions will be less likely to do so. However, the CMB cold spot is anomalously cold, inconsistent with an origin at the last-scattering surface. (Credit: E.M. Huff, SDSS-III/South Pole Telescope, Zosia Rostomian)

According to the theory of inflation, there should be a very specific set of fluctuations that the Universe starts with at the onset of the hot Big Bang. In particular:

  • the fluctuations should be Gaussian, which means they should follow a Bell Curve-like distribution about some average,
  • they should be approximately the same amplitude on all scales, with larger cosmic scales having slightly greater fluctuations by only a few percent than the smaller ones,
  • these fluctuations should all be adiabatic (with constant entropy) in nature, with none of them being isocurvature (the other option) in nature,
  • and that as the Universe expands, these fluctuations should begin to gravitationally collapse on small scales first, with larger scales only catching up once the cosmic horizon has grown to a certain size.

All of these predictions have since been borne out and confirmed by observations, some to within the limits of our measurement precision and others quite spectacularly.


The fluctuations in the CMB are based on primordial fluctuations produced by inflation. In particular, the ‘flat part’ on large scales (at left) have no explanation without inflation. The flat line represents the seeds from which the peak-and-valley pattern will emerge over the first 380,000 years of the Universe, and is just a few percent lower on the right (small-scale) side than the (large-scale) left side. (Credit: NASA/WMAP science team)

However, it’s always worth looking for anomalies, as no matter how thoroughly your predictions agree with reality, you must always put ahead, hoping to uncover something unexpected. After all, it’s the only way you can discover something new: by looking as you’ve never looked before. If you have specific predictions and expectations for what your Universe is going to look like, then anything that defies your expectations is — at the very least — worth a second look.

Perhaps the most unusual remaining feature that we see in the microwave sky, once we subtract out the effect of the Milky Way galaxy, is the fact that there’s a cold spot that doesn’t align with these theoretical explanations. Once we’ve quantified the types and scales of temperature fluctuations that ought to exist, we can correlate them together, and see how fluctuations on smaller and larger scales should be related.

In one particular region of space, we find that there’s a very deep cold spot: about 70 microkelvin below the average temperature on a relatively large angular scale. Moreover, that cold spot appears to be encircled by a hotter-than-average region, making it even more anomalous. To many, the cold spot in the CMB represented a potential challenge to inflation and the standard cosmological model, as it wouldn’t make sense if the Universe was somehow born with this anomalously low-temperature region.


The quantum fluctuations that occur during inflation get stretched across the Universe, and when inflation ends, they become density fluctuations. This leads, over time, to the large-scale structure in the Universe today, as well as the fluctuations in temperature observed in the CMB. Its a spectacular example of how the quantum nature of reality affects the entire large-scale universe. (Credit: E. Siegel; ESA/Planck and the DOE/NASA/NSF Interagency Task Force on CMB research)

It’s important to recognize where these temperature fluctuations come from in the first place. The Universe, even at the start of the hot Big Bang, really is the exact same temperature everywhere. The thing that’s different from location to location is the density of the Universe, and this is the component that has those 1-part-in-30,000 imperfections, as imprinted by inflation. The reason we observe the Universe to possess different temperatures in different regions of space is because of the phenomenon of gravitational redshift: matter curves space, and where space is more severely curved, light has to lose more energy to “climb out” of that gravitational potential well. In the astrophysics community, this is known as the Sachs-Wolfe effect, and it’s the primary cause of the temperature differences we observe in the CMB.

But there’s another, more subtle effect: the integrated Sachs-Wolfe effect. As structure forms in the Universe, as gravitation brings more and more mass together, as clusters grow and voids form, and as the relative ratios of radiation, matter, and dark energy change with respect to one another, the gravitational effects of traveling into a certain region of space don’t necessarily equal the gravitational effects of traveling out of that same region of space later on. The Universe evolves, structures form and become more matter-rich in some areas and more matter-poor in others, and any light passing through those regions is affected.


When we see a hot spot, a cold spot, or a region of average temperature in the CMB, the temperature different we see typically corresponds to an underdense, overdense, or average-density region at the time the CMB was emitted: just 380,000 years after the Big Bang. This is a consequence of the Sachs-Wolfe effect. (Credit: E. Siegel/Beyond the Galaxy)

Imagine, if you will, that you have two different regions of space: a large-scale overdensity (like a supercluster) and a large-scale underdensity (like a great cosmic void). Now, imagine, just like in our real Universe, you have some form of dark energy: a component of the Universe that behaves differently from matter, and doesn’t dilute in density as the Universe expands. Now, let’s imagine what happens as the photon, traveling through space, encounters either a big overdensity or a big underdensity.

As the photon begins to see this overdensity (underdensity), it gains (loses) energy as it travels from an average region of space into the new region that departs significantly from the average density.

But owing to dark eergy, the gravitational potential well (hump), whether positive or negative, becomes stretched out and gets more shallow, and does so as the photon travels through it.
As a result, when the photon exits the overdense (underdense) region, it re-loses (or re-gains) a smaller amount of energy than it gained (lost) when it first entered that region.

If something appears anomalously cold in the CMB, it could be because there’s something wrong with our model of the Universe; that’s of course the more interesting option. But it could also be, quite simply, because there’s a large cosmic void in that location, and that void grew shallower as the light traveled through it because of dark energy.


The anomalous cold spot in the CMB, as viewed by Planck, is unusual not only for its coldness and its extent, but for the fact that it’s surrounded by a hot region on all sides. This puzzling feature may be explicable by the recent discovery of a new, nearby supervoid in the constellation of Eridanus. (Credit: A. Kovács et al., 2021, MNRAS)

Now, here’s where the idea becomes testable: you can’t point to a void that’s too far away along the line-of-sight to explain it, because dark energy only becomes important for the Universe’s expansion over the past ~6 billion years or so. If one exists along this line-of-sight, it must be closer, at present, than 7.5 billion light-years.

So, what do we find when we go out and look?

That’s where the latest results from the Dark Energy Survey come in. Scientists were able to confirm that, yes, there is a supervoid there, and it may have a much higher-amplitude integrated Sachs-Wolfe effect that a typical underdensity does. While some underdensities were previously found at greater distances some 6-10 billion light-years away, they were determined to account for no more than ~20% of the effect. However, a 2015 study revealed a nearby supervoid right in that precise direction: 1.9 billion light-years away and about 0.5-1.0 billion light-years across. The most recent study that confirms this void and measures its properties, finds that it’s the largest supervoid that exists since the onset of dark energy’s dominance. The study suggests — but doesn’t yet prove — that there is a causal relation between this late-time supervoid and the “cold spot” in the CMB.


The Cold Spot resides in the constellation Eridanus in the southern galactic hemisphere. The inset shows the microwave temperature map of this patch of sky, as mapped by the European Space Agency Planck satellite. The main figure depicts the map of the dark matter distribution created by the Dark Energy Survey team. Note how the large supervoid thoroughly coincides with the CMB’s cold spot. (Credit: Gergö Kránicz and András Kovács)

There are many different ways to map out the large-scale structure of the Universe: from galaxy counts to gravitational lensing to the overall impact that the structure has on the background light emitted from various redshifts. In this particular case, it was the construction of a gravitational lensing map that confirmed the presence of this supervoid, which happens to be the emptiest large region of space in our nearby corner of the Universe. We cannot say for certain that this supervoid explains the full extent of the CMB cold spot, but it’s looking more and more likely that, once the presence of the supervoid is taken into account, what remains is no more anomalous than any other typical region of the sky.

The way we’ll tell for sure, of course, is through better, deeper, higher-resolution imaging of this relatively large region of the sky, which spans somewhere around 40 square degrees. With the ESA’s Euclid mission poised to launch just next year, in 2023, and with the Vera Rubin Observatory and NASA’s Nancy Grace Roman Telescope expected to come online over the next few years, the critical data will soon be in our hands. After nearly two decades of wondering at what could have caused the CMB cold spot, we finally have our answer: the largest supervoid in the nearby Universe. All we need is a robust confirmation of what the present data strongly indicates, and this will be yet another cosmic challenge to which our standard cosmological model is thoroughly capable of rising.
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