For decades, scientists believed they had a pretty good idea of how the Universe worked. But with the deployment of Webb, a number of discoveries have emerged that are challenging this assumption.
Host | Matthew S Williams
On ITSPmagazine 👉 https://itspmagazine.com/itspmagazine-podcast-radio-hosts/matthew-s-williams
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Episode Notes
For decades, scientists believed they had a pretty good idea of how the Universe worked. But with the deployment of Webb, a number of discoveries have emerged that are challenging this assumption. As new discoveries challenge old assumptions, scientists are beginning to wonder. Is the Standard Model of Cosmology wrong, or does it just need some adjustments?
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Resources
Cosmology - Harvard & Smithsonian Center for Astrophysics: https://www.cfa.harvard.edu/research/science-field/cosmology
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For more podcast Stories from Space with Matthew S Williams, visit: https://itspmagazine.com/stories-from-space-podcast
Is the Standard Model of Cosmology Wrong? | Stories From Space Podcast With Matthew S Williams
[00:00:00] The authors acknowledged that this podcast was recorded on the
traditional unseated lands of the Lekwungen peoples. Hello and welcome back
to Stories From Space. I'm your host, Matt Williams, and today I wanted to talk
about a subject that is of growing concern among astronomers and
cosmologists, and it has to do with what's known as the standard model of
cosmology.
Basically our understanding of how the universe fits together, how it works, as
well as its origins and its possible fate, and specifically the growing concern I
mentioned has to do with whether or not this model is in fact the correct one.
Now this is hardly a new concern. As with any accepted scientific theory, there
have been detractors and people who have raised questions and challenges to
the standard model for a very long time.
As long as it's been the [00:01:00] predominantly accepted model of how the
universe works. There have been those who spoke out against it and challenged
it. These concerns and or challenges may have reached a point of inflection
thanks to discoveries made by the James Webb Space Telescope, the dark
energy survey, and the dark energy spectroscopic instrument after decades of
being the most widely accepted model of cosmology.
New data is indicating that scientists could be wrong on a few key points in that
model. But before we get into what those findings are, we first need a quick
review of what the standard model of cosmology essentially states. Basically,
it's known as the Lambda CDM model. Lambda stands for dark energy or the
cosmological constant.
Essentially the force that is causing the universe to expand over time. CDM
refers to cold, [00:02:00] dark matter, the prevailing theory of dark matter that
states that space is filled with a mysterious, invisible mass that accounts for
roughly 85% of the total mass of the universe together. Dark matter and dark
energy account for 95% of the mass energy density of the universe.
The remaining 5% is made up of ordinary or bar matter, which is the kind of
matter that we can see, stars, planets, galaxies, cosmic dust, asteroids, you name
it. As for how scientists arrived at this model, that requires a bit of a history
lesson, so please get comfortable and get ready for some serious name
droppings.We start by visiting Einstein back in the early 20th century when he was putting
his finishing touches on the theory of relativity. Einstein had already led a
revolution in science in [00:03:00] 1905, where he synthesized and crystallized
a lot of experimental data and theory by proposing that light traveled at a
constant speed in a vacuum regardless of the motion of the observer or the
source.
While also maintaining that the laws of physics were the same for all inertial
reference frames, which was a guiding principle of science and cosmology for
hundreds of years at this point. Now, this theory known as the special theory of
Relativity was meant to explain the behavior of light, which seemed rather
anomalous because conventional theory dictated that.
Depending upon the motion of the observer and the source, the speed at which
light reaches us would change. And this was based on Galilean in variance or
Galilean relativity, which itself was used to describe the motions of the planets
and how [00:04:00] humanity was part of an inertial reference frame, AKA
Earth.
Not only rotating on its axis, but orbiting the sun. And that applied to the Copan
heliocentric model of the universe, which Galileo refined. He was able to show
scientists of his day that in fact, all observations of the heavens. Up until that
point, the reason why they were inconsistent or failed to predict the motions of
the planets was because Earth itself was moving.
And so scientists in the late 19th and early 20th centuries when measuring the
speed of life, they found much to their surprise that the speed did not change
based on the source and based on whether or not Earth was moving towards or
away from that particular source. Whereas scientists prior to Einstein had
suggested that this may be due to a mysterious ether that filled space and was
responsible for either dragging light, slowing it down, [00:05:00] or moving it
along, propagating it all experiments to test the effects of this ether all turned up
negative.
In all cases. The speed of light was constant and consistent to which Einstein
had suggested instead that. Scientists were thinking about space and time all
wrong, for which he proposed that scientists were essentially looking at the
wrong side of things. Instead, he proposed a four dimensional space time
framework in which time was not absolute or independent of motion and
velocity, which is something that Galilean relativity or in variance treated as a
given.And that time itself was relative to the observer. And that depended upon their
inertial reference frame. It depended upon their velocity and whether or not they
were accelerating. And he boiled this all down to e equals mc squared Energy
equals mass times acceleration [00:06:00] towards the speed of light. And this
theory, it had significant implications almost right out of the gate, almost right
away, scientists accepted his conclusions and his equations because they
simplified everything.
They're consistent with all the experimental results, and it did away with any
extraneous explanations such as the whole Ether idea. However, the deeper
implications, which were things that Einstein himself would expound on in
subsequent papers, these included what's known as mass energy equivalents,
because if you look at the equation equals mc.
What emerges from it is the fact that energy and mass, if you switch the
Miranda in this equation, everything still remains balanced so that in fact mass
and energy are just flip sides of the same coin. And the other being the
aforementioned four dimensional space time concept, that space and [00:07:00]
time are not distinct, that they are in fact part of the same framework and last,
that the speed of light is invaluable.
Meaning nothing can go faster than light because in accordance with e equals
mc square and the mass energy equivalence, it would take more and more
energy to accelerate closer and closer to the speed of light, to the point that
you'd have to generate infinite energy to actually attain it, and that your inertial
mass in the process, which would just keep getting heavier and heavier as you
approached it, would also become infinite.
So neither proposition is possible, therefore the speed of light is absolute. And
so from that, Einstein began over the next decade to attempt to reconcile his
theory with gravity, because much like motion and velocity and Galilean
relativity. Scientists believed that they had [00:08:00] gravity figured out too.
And this was all summarized and crystallized by a previous great scientist, sir
Isaac Newton, but key to Isaac Newton's universal gravitation. And his theories
on motion was the notion that gravity emerged as a natural product of point
sources of mass. And that the gravitational interaction between objects, this was
an instantaneous force and it depended upon the object's mass and their distance
from each other.
As Einstein demonstrated, nothing in the universe was instantaneous. Light
traveled at a set speed, which was absolute. So information in our universe andthe physical forces that govern it, they do not arise spontaneously or
instantaneously. They take time travel. And so he [00:09:00] began to rethink
gravity as not a point source attraction between two objects, but rather an effect
that massive objects had on the very fabric of space time itself.
And he was partly inspired by all the revolutionary work in electromagnetism
and quantum mechanics. That established that electromagnetic phenomenon. It
works in terms of fields. So he began to think of gravity as a field. Similarly, he
was inspired by the fact that gravity wasn't distinct at all from acceleration,
which was a key part of special relativity.
So he envisioned gravity as something that is exerted by mass and it alters the
curvature of space time around it, causing any objects that are in its vicinity to
trace that curvature and to be accelerated, thus altering their perception of time.
[00:10:00] And also bending the pathway. That light will follow around it.
And this was confirmed shortly after Einstein put the finishing touches on his
theory of general relativity, as it was now called, and this was done by the
edington experiment in which astronomers actually witnessed spacetime
bending by looking at the sun during a complete solar eclipse, and noting that
stars that were in the background that should have been obscured by the sun
actually appeared visible, adjacent to it.
And this is in keeping with Einstein's predictions and also his field equations.
Basically, the stars appeared to be exactly where his math and his numbers
would place them at. And similar experiments have been carried out ever since,
involving larger and larger, massive objects up to and including super massive
black holes.[00:11:00]
And they've all shown that general relativity is in fact correct. And experiments
with atomic clocks have shown the same thing clocks that are in space and are
less subject to earth's acceleration from its gravitational field. They record time
at a different rate than similar atomic clocks running down here on the surface
of the planet.
And so general relativity became fundamental to modern day cosmological
models. Interestingly enough, the existence of black holes was something that
had been inferred long before any observations of black holes were possible.
And it was based on Einstein's field equations yet again. In particular the work
of Carl Schwartz, child and Superman and Chandras car.They both worked with Einstein's field equations on general relativity and found
that theoretically there could be a class of stars so massive that when [00:12:00]
they underwent collapse at the end of their lifespan. A gravitational object so
compact that nothing including light would be able to escape because the
acceleration, the gravitational exerted would actually equal the speed of light.
And by the 1950s and seventies, these early findings would have significant
implications as scientists were able to realize for the first time. How prevalent
and how massive black holes could get. Well, before that, something else
occurred in the field of astronomy that left Einstein feeling a little deflated, and
astrophysicists and cosmologists.
Very intrigued. And that was the revelation that the universe was in fact
expanding. Two astronomers in particular noted, and these were [00:13:00]
none other than George Lara, a Belgian priest, astronomer, physicist
Cosmologist, and Edwin Hubble, an American astronomer, cosmologist
physicist, et cetera, both of whom demonstrated with improved instruments and
observations that were available at the time.
That those distant galaxies, that astronomers were now able to study in greater
detail that they were receiving from our galaxy. And the greater their distance,
the more they were receiving. And this contradicted Einstein's own views on
cosmology, which he had been espousing at the time, and debating with George
La Matri himself.
As the way Einstein saw it, the universe was a static and eternal place that was
not subject to any serious changes, and he was motivated to do this because it
was his own general [00:14:00] relativity field equations that implied that the
universe was likely to be expanding. That space was a function of time, and the
universe was therefore likely to.
And this was why in 1917, he added a parameter to his field equations, which
was denoted by the Lambda figure, which he called the cosmological constant,
which in his mind was a force that counteracts gravity, that kept gravity in
check, and ensured that the galaxies remained in a nice state of equilibrium,
either expanding nor contracting.
But as his contemporaries observed, depending upon the value of the
cosmological constant, the universe could in fact be expanding. In any case,
things culminated. In 1931 when Einstein visited Hubble at the Mount Wilson
Observatory, [00:15:00] where he stationed it, looked over his observations, and
he declared himself convinced.He said that the cosmological constant was the greatest blunder of his career,
and that in fact, the universe was in the state of expansion. But as time went on
and our observations of the universe breached farther and became a lot more
detailed, scientists would come to believe that Einstein was more right than he
thought and more right than he wanted to be.
In many cases ranging from cosmology to quantum physics, Einstein was
responsible for discoveries he didn't like. However, before that would happen,
there were a number of discoveries made, which Einstein having passed away in
1955 would not get to witness. And these discoveries happened in what is
known as the golden age of general [00:16:00] relativity.
Which lasted from 1960 to the mid seventies thereabouts. And one of the most
groundbreaking discoveries of this time was the discovery of the cosmic
microwave background. You see, one of the greatest implications or
consequences of Einstein's theory, of general relativity on the one hand, and
Hubble and LaMere is demonstrating that the cosmos is expanding.
Was the question of the universe's ultimate fate, but more contentiously its
origins. Because if the universe is in fact in a state of expansion, then
astronomers naturally ventured that at one time it must have occupied a much,
much smaller volume space. And this led to what is known today as the great
debate.
And on the one side, you had people like Lamare and Hubble. Who argued
[00:17:00] that the universe began as a single point in space as a singularity
from which all matter and energy were created in a giant explosion, which gave
rise to cosmic inflation, the birth of the first stars in galaxies. Which came
together to form the large scale structure of the universe as we see today, which
continues to expand.
On the other hand, you had proponents of the steady state hypothesis, which
stated that not all matter and energy were created in a single event, and that new
galaxies will emerge all the time in the universe as time and space continue to
grow and expand. And to people on this side of the aisle. The other side was
known as the Big Bang Hypothesis Crowd, and this was meant as a bit of a
playful pejorative, but interestingly enough, the name stuck.
Furthermore, they also believe that proponents like [00:18:00] George La Metra
preferred this theory due to, in part religious bias. George La Metra was a priest,
and therefore, the idea of a single creation event must have sounded likesomething at a genesis. However, neither side could produce evidence that
definitively showed that their interpretation was correct until the 1960s.
A key point in the whole debate was that if the universe emerged from a big
bang, that there would be some relic radiation left over that would be visible in
all directions. And by measuring the time it took that radiation to reach Earth,
astronomers would be able to put accurate constraints on the age of the
universe.
And this is precisely what happened by the 1960s. When astronomers who had
been looking at the universe through microwave filters to identify cosmic
sources of microwave irradiation, [00:19:00] they found a persistent signal that
was coming from all directions. Very, very faint and very, very distant. And
after a lot of follow-up observations and attempts to measure the radiation and
the distance that it had traveled, scientists concluded that this was in fact the
relic radiation of the Big Bang, which all but ended the debate.
There are still proponents of the steady state hypothesis today who will use
inconsistencies between our theories and our observations to, to suggest their
alternative model. Nevertheless, the Big Bang went on to become a established
part of the predominantly accepted cosmological model. The universe as this
model states began with the Big Bang and has been expanding ever since.
Another key discovery to come out of [00:20:00] the golden age of general
Relativity occurred in the 1970s when an American astronomer Vera Creen, for
which the Vera Creen Observatory is now named, observed a problem with
spiral galaxies. In short, she noticed that the rotational curves of these galaxies,
the speed at which they spun, especially the stars in their outer edges.
Was much more rapid than their visible mass would imply. And this built on
previous work by the Swiss by Swiss astronomer, Fritz Zuki, who noted similar
anomalies in 1933 when he was observing the coma cluster. A large grouping of
galaxies. Uh, to explain this, both Vicki Ruben and her contemporaries, they
ventured that, in fact, there had to be more mass there that we weren't aware of
because in accordance with Einstein's field equations, the rotation speed of a
[00:21:00] galaxy is very much an expression of its mass.
And if galaxies were observed rotating this quickly. Then clearly they had to be
more massive than they appeared, and this gave rise to the theory that the
universe was filled with a mysterious mass that did not interact with normal
matter via electromagnetic forces, meaning that it was not visible in visible
light, and so the term dark matter began to enter into common usage.More than that, it became an accepted part of the most widely accepted
cosmological model. Uh, just like the Big Bang, there are proponents of an
alternative theory known as modified Newtonian Dynamics, which argues that
the universe is not filled with dark matter, and then in fact gravity behaves
differently on the macro scale.
And here too, proponents of this alternative theory, they will [00:22:00] reassert
it. Whatever discrepancies arise in our current cosmological model and new
discoveries are inconsistent with it. The next big contribution came in the 1990s
thanks to the deployment of the Hubble Space Telescope. Hubble was the first
of its kind, and it was able to do something that no other telescopes could do at
the time.
By making observations from space, it was able to avoid atmospheric
interference and therefore able to see farther and clear. Than any instrument
ever had. Initially, it pushed the boundaries of what astronomers could observe
in our universe. From roughly 4 billion light years to 10 billion per loan was
amazing, but thanks to the hell old deep fields and ultra deep fields, it was able
to push that even [00:23:00] farther to 13 billion light years.
Now due to increasingly accurate and refined measurements of the cosmic
microwave background and the distance that its light travel to reach us.
Astronomers have come up with a modern and current estimate of roughly 13.8
billion light years, which essentially means that give or take a few eons, the
universe is just shy of 14 billion years old.
Which basically means that thanks to Hubble Astronomers were able to
visualize up to 93% of cosmic history and were able to track the evolution of
galaxies and larger cosmic structures from that point right on up to the present.
It, and this reveals something very interesting and unexpected as we covered in
a previous episode.
Which looked at the [00:24:00] Hubble tension. The purpose of the Hubble
Space Telescope, among other things, was to measure the Hubble metric or the
Hubble LA metric. Which is to say the rate at which the cosmos is expanding,
which is why the Hubble Space Telescope is so named. The problem was that
up until this point, and certainly since astronomers, astrophysicists and
cosmologists believe that the expansion of the cosmos was constant, which is
why the principle that describes cosmic expansion is also known as the Hubble
la Matri constant.What, according to hubble's observations, looking at galaxies that were the
earliest galaxies in the universe that were actually observable, invisible light
astronomers obtained two rather different values for cosmic expansion. In the
earlier universe, [00:25:00] they obtained one value, whereas local
measurements, which looked at more recent cosmic history were quite another.
And these two results basically indicated that the universe was expanding at a
more rapid pace during the last 4 billion years of cosmic history. And
interestingly enough, this led to a rethink of Einstein's cosmological constant
because as scientists had speculated previously, depending upon the value of the
constant, the universe could be in a state of expansion.
And this certainly seemed to be the case based on these observations, or more
specifically that the universe had been expanding from the beginning. But as
large scale, cosmic structures got farther apart, the mutual attraction of gravity
became lessened. And so expansion sped up [00:26:00] and this provided the
last parameter of the standard model of cosmology.
Represented by the Lambda figure as Einstein originally proposed. But of
course, there's also the caveat that the dark matter in this model is cold, which is
to say that it's composed of larger particles that do not move as rapidly as they
would in the case of a hot, dark matter model where the particles are smaller
and move more freely, thereby generating more energy.
Which has been the predominantly held view of cosmologists and
astrophysicists. Though of course there are dissenting opinions and new
research may affect a transition in that respect. In summary, this is how our
current understanding of the universe came to be. It combines general relativity
with Einstein's speculation [00:27:00] of there being a force that holds back
gravity.
Along with key contributions by Hubble and Lame and other astronomers that
revealed that the universe is expanding and the discovery of the CMB, which
confirmed that in fact the universe was created through a massive explosion,
AK the Big Bang, and it has been expanding ever since. And finally, there are
the decades worth of observations that fueled speculation.
That the majority of mass in the universe is in fact not visible in the visible light
spectrum and that the mass energy density is overwhelmingly composed. 95% is
noted of things we don't see, not unlike black holes, which are invisible in
optical light, but are discernible based on the effects they have on surrounding
space time.[00:28:00]All that matter. They pull in into a disc around them, which is accelerated to
close to the speed of light, and pumps out so much radiation that the center of
galaxies that have super massive black holes, they become brighter than all the
stars in the entire disc combined. And that is how the standard model of
cosmology came to be.
And why? It's the most widely held view of how the universe came to be and
where it's going. Which brings us to the recent revelations by web. Which as
noted, revealed things about the very early universe, which is to say less than a
billion years after the Big Bang. It revealed a number of what are known today
as Little Red Dots, and these were some of the earliest galaxies that ever
existed, and which appeared to be highly compact [00:29:00] and very red.
And as we noted in a previous episode. The way we had observed more galaxies
than expected in the early universe, which seemed larger and more populated by
stars than expected. This already caused a bit of a shakeup in our current
cosmological models, but the existence of these little reg dots also presented a
real mystery to astronomers.
On the one hand, there were those who believed that they were. Very dense
galaxies of large clusterings of stars, hence their apparent brightness and that
they were also filled with lots of cosmic dust. Hence why they're red. And this
is similar to what are known as dusty galaxies that have been observed in more
recent cosmic history.
However, believe that the reason for these compact galaxies being [00:30:00]
rather bright was in fact that they were early examples of quasars. Active
galactic nuclei, which as previously mentioned are caused by a super massive
black hole at the center of a galaxy, which generates so much energy from all
the in falling matter of gas and dust, which is then accelerated to close to the
speed of light that this pumps out all that bright energy.
And between these two camps, there's yet to be a clear resolution, although it
was recently suggested by a research team that both of these interpretations
could be correct and that they represent different evolutionary stages of very
early galaxies. So on the one hand, you have the stellar only interpretation,
where these early galaxies were packed full of stars.
And this led to collisions of stars in the most densely packed [00:31:00] region,
directly in the center of the galaxies, which led to the formation of massive
black holes, which on its own was known as the Black Hole and Galaxy
Interpretation. And last, but certainly not least, in fact, perhaps the mostprofound revelation was that cosmic expansion during this time, during the first
billion years after the Big Bang, was actually faster than it was by about a
billion years later, which would indicate that cosmic expansion was initially
fast, then slowed down and began accelerating yet again, roughly 4 billion years
ago.
And so as we covered in the previous episode that looked at what Webb has
revealed so far about the cosmos, this led some scientists to consider the
possibility that there was something known as early dark energy. And the same
thing. This revelation has caused [00:32:00] astronomers and cosmologists to
once again, consider that dark energy may not be a constant force, but rather a
dynamic one.
That subject to DEC over time and has been subject to accelerations and
slowdown in the past, which also has significant implications for fate of the
universe that contradict what many previously thought prior to Hubble
astronomers believe that cosmic expansion would eventually slow down and the
universe would contract, and the big crunch scenario emerged from that.
Whereas after Webb made its observations that confirmed that cosmic
expansion was speeding up, the predominantly held view became either the big
rip or the heat desk scenario. In the former, the universe would continue to
accelerate in its expansion until eventually the fabric of space time itself would
be ripped apart.
The [00:33:00] heat death scenario is similar in that the universe would continue
to expand until all the stars in the cosmos. Even the red dwarfs that can live for
trillions of years would eventually wink out and there would be no lights, no
heat left, however. If dark energy is in fact dynamic, then what is likely to
happen is that the universe will slow in its expansion, eventually stopping, but it
will not contract.
Instead, all the stars in the universe will go through their main sequence phase.
They will die. Eventually, the red dwarfs will wink out, and this will lead to
what is known as the big freeze scenario. And this is similar to the heat death
scenario, but with the caveat that the universe would not still be expanding at
the time.
And so as indicated, this has led to a rethink of a lot [00:34:00] of the
assumptions upon which the Lambda CDM model is based. Nevertheless, it still
holds for.It doesn't look like we'll be throwing it out anytime soon. In any case, thank you
for listening and be sure to tune in next time where the topic will be Interstellar
Objects, which have once again become a rather popular topic. Thanks to the
ongoing investigations and observations of three I Atlas. The Interstellar
comment, which has exhibited some strange behaviors that has, once again,
field speculation that it may not be a naturally occurring object, but an
interstellar emissary or possibly a derelict probe of some kind.
We will be getting into that. We'll also be taking a look at Panspermia. The
[00:35:00] theory that the ingredients for life are distributed throughout the
universe by interstellar objects such as asteroids and comets, and which may
even apply to rogue planets and stars that get kicked out of their galaxies from
time to time.
And of course, we'll also have some more exciting interviews with researchers,
scientists, and people who are at the forefront of aerospace and space
exploration today. Expect all that. And in and in. Thank you for listening. I'm
Matt Williams. Been stories.