Certain subsectors of the scientifically-oriented blogosphere are abuzz — abuzz, I say! — about this new presentation on Dark Energy at the Hubblesite. It’s slickly done, and worth checking out, although be warned that a deep voice redolent with mystery will commence speaking as soon as you open the page.
But Ryan Michney at Topography of Ignorance puts his finger on the important thing here, the opening teaser text:
Scientists have found an unexplained force that is changing our universe,
forcing galazies farther and farther apart,
stretching the very fabric of space faster and faster.
If unchecked, this mystery force could be the death of the universe,
tearing even its atoms apart.We call this force dark energy.
Scary! Also, wrong. Not the part about “tearing even its atoms apart,” an allusion to the Big Rip. That’s annoying, because a Big Rip is an extremely unlikely future for a universe even if it is dominated by dark energy, yet people can’t stop putting the idea front and center because it’s provocative. Annoying, but not wrong.
The wrong part is referring to dark energy as a “force,” which it’s not. At least since Isaac Newton, we’ve had a pretty clear idea about the distinction between “stuff” and the forces that act on that stuff. The usual story in physics is that our ideas become increasingly general and sophisticated, and distinctions that were once clear-cut might end up being altered or completely irrelevant. However, the stuff/force distinction has continued to be useful, even as relativity has broadened our definition of “stuff” to include all forms of matter and energy. Indeed, quantum field theory implies that the ingredients of a four-dimensional universe are divided neatly into two types: fermions, which cannot pile on top of each other due to the exclusion principle, and bosons, which can. That’s extremely close to the stuff/force distinction, and indeed we tend to associate the known bosonic fields — gravity, electromagnetism, gluons, and weak vector bosons — with the “forces of nature.” Personally I like to count the Higgs boson as a fifth force rather than a new matter particle, but that’s just because I’m especially fastidious. The well-defined fermion/boson distinction is not precisely equivalent to the more casual stuff/force distinction, because relativity teaches us that the bosonic “force fields” are also sources for the forces themselves. But we think we know the difference between a force and the stuff that is acting as its source.
Anyway, that last paragraph got a bit out of control, but the point remains: you have stuff, and you have forces. And dark energy is definitely “stuff.” It’s not a new force. (There might be a force associated with it, if the dark energy is a light scalar field, but that force is so weak that it’s not been detected, and certainly isn’t responsible for the acceleration of the universe.) In fact, the relevant force is a pretty old one — gravity! Cosmologists consider all kinds of crazy ideas in their efforts to account for dark energy, but in all the sensible theories I’ve heard of, it’s gravity that is the operative force. The dark energy is causing a gravitational field, and an interesting kind of field that causes distant objects to appear to accelerate away from us rather than toward us, but it’s definitely gravity that is doing the forcing here.
Is this a distinction worth making, or just something to kvetch about while we pat ourselves on the back for being smart scientists, misunderstood once again by those hacks in the PR department? I think it is worth making. One of the big obstacles to successfully explaining modern physics to a broad audience is that the English language wasn’t made with physics in mind. How could it have been, when many of the physical concepts weren’t yet invented? Sometimes we invent brand new words to describe new ideas in science, but often we re-purpose existing words to describe concepts for which they originally weren’t intended. It’s understandably confusing, and it’s the least we can do to be careful about how we use the words. One person says “there are four forces of nature…” and another says “we’ve discovered a new force, dark energy…”, and you could hardly blame someone who is paying attention for turning around and asking “Does that mean we have five forces now?” And you’d have to explain “No, we didn’t mean that…” Why not just get it right the first time?
Sometimes the re-purposed meanings are so deeply embedded that we forget they could mean anything different. Anyone who has spoken about “energy” or “dimensions” to a non-specialist audience has come across this language barrier. Just recently it was finally beaten into me how bad “dark” is for describing “dark matter” and “dark energy.” What we mean by “dark” in these cases is “completely transparent to light.” To your average non-physicist, it turns out, “dark” might mean “completely absorbs light.” Which is the opposite! Who knew? That’s why I prefer calling it “smooth tension,” which sounds more Barry White than Public Enemy.
What I would really like to get rid of is any discussion of “negative pressure.” The important thing about dark energy is that it’s persistent — the density (energy per cubic centimeter) remains roughly constant, even as the universe expands. Therefore, according to general relativity, it imparts a perpetual impulse to the expansion of the universe, not one that gradually dilutes away. A constant density leads to a constant expansion rate, which means that the time it takes the universe to double in size is a constant. But if the universe doubles in size every ten billion years or so, what we see is distant galaxies acceleratating away — first they are X parsecs away, then they are 2X parsecs away, then 4X parsecs away, then 8X, etc. The distance grows faster and faster, which we observe as acceleration.
That all makes a sort of sense, and never once did we mention “negative pressure.” But it’s nevertheless true that, in general relativity, there is a relationship between the pressure of a substance and the rate at which its density dilutes away as the universe expands: the more (positive) pressure, the faster it dilutes away. To indulge in a bit of equationry, imagine that the energy density dilutes away as a function of the scale factor as R-n. So for matter, whose density just goes down as the volume goes up, n=3. For a cosmological constant, which doesn’t dilute away at all, n=0. Now let’s call the ratio of the pressure to the density w, so that matter (which has no pressure) has w=0 and the cosmological constant (with pressure equal and opposite to its density) has w=-1. In fact, there is a perfectly lockstep relation between the two quantities:
n = 3(w + 1).
Measuring, or putting limits on, one quantity is precisely equivalent to the other; it’s just a matter of your own preferences how you might want to cast your results.
To me, the parameter n describing how the density evolves is easy to understand and has a straightforward relationship to how the universe expands, which is what we are actually measuring. The parameter w describing the relationship of pressure to energy density is a bit abstract. Certainly, if you haven’t studied general relativity, it’s not at all clear why the pressure should have anything to do with how the universe expands. (Although it does, of course; we’re not debating right and wrong, just how to most clearly translate the physics into English.) But talking about negative pressure is a quick and dirty way to convey the illusion of understanding. The usual legerdemain goes like this: “Gravity feels both energy density and pressure. So negative pressure is kind of like anti-gravity, pushing things apart rather than pulling them together.” Which is completely true, as far as it goes. But if you think about it just a little bit, you start asking what the effect of a “negative pressure” should really be. Doesn’t ordinary positive pressure, after all, tend to push things apart? So shouldn’t negative pressure pull them together? Then you have to apologize and explain that the actual force of this negative pressure can’t be felt at all, since it’s equal in magnitude in every direction, and it’s only the indirect gravitational effect of the negative pressure that is being measured. All true, but not nearly as enlightening as leaving the concept behind altogether.
But I fear we are stuck with it. Cosmologists talk about negative pressure and w all the time, even though it’s confusing and ultimately not what we are measuring anyway. Once I put into motion my nefarious scheme to overthrow the scientific establishment and have myself crowned Emperor of Cosmology, rest assured that instituting a sensible system of nomenclature will be one of my very first acts as sovereign.
To JM I would recommend trying to read some literature out there. A part of the problem is that as you admitted your mathematics education stopped at trigonometry. I picked up a masters in math while doing my doctoral work in physics. There is a huge gap here, and without trying to sound patronizing I can only say that there simply is no way that you have a particularly sound understanding of these things. I say this based on some of the things you have been writing here.
A cardinal rule of physics and cosmology is that things are point of view independent (POVI). In the expanding universe all observers will see the universe expanding away from them. With what you are trying so say it appears that our galaxy is on a perferred coordinate system. What we observe of the universe is a “cooling remnant” of a singularity, but it is a spacelike singularity. As we look back in time we see events further back in time. This singularity contains all the “data” for the structure of the universe. In what you are saying if there were no correlation between z and the observation back in time is that the singularity is timelike. This singularity would have no event horizon around it, or a chronology protection of an initial spacelike singularity. This would mean our universe is subject to all sorts of horrible pathologies, including closed timelike loops or past time travel. In other words you are removing the conceptual problems you have with comoving frames and expansion by introducing something into the universe that would make it logically contradictory.
I could go on with this, in particular the Hawking-Penrose energy conditions and other matters. Yet I think that would not go far. So I can only state this as a matter “fact.” Science proceeds a bit like a medical diagnosis. You check the most likely diagnosis, if that fails certain tests you eliminate that and go onto the next most likely and so forth. The current theoretical model of the universe has been arrived at in just this way. In its general outline the expanding eternal inflationary cosmology appears to be what we exist within.
Lawrence B. Crowell
Lawrence B. Crowell
Lawrence,
I’m certainly not saying that our galaxy is a preferred coordinate system. If space is curved out, by expanding radiation, as it is curved in by collapsing mass, then every point is the center of its own coordinate system and every other source of light is going to appear to be receding, ie. redshifted directly away from it by this effect. Although other factors, such as gravity and velocity are going to distort it.
The problem with the essentially top down, noun, form oriented view of reality is that it is a linear search for ultimate form, yet everything that can be grasped, whether it’s mass collapsing into a black hole, or energy radiating away to nothingness, is that it is a linear unit of time, going from beginning to end. Safe to say the people locked in this view will go to their death, convinced by their own end, that all of reality is on the same path, from start to finish.
There are two sides of the coin, but when these people turn the coin over, it vanishes into motion and all they can see are many coins, all moving around, so they see it as one one vs. many, rather then form vs. function. Consider string theory; Everyone is obsessed with finding out what the strings are, yet they turn into a labyrinth of dimensions. What they ingore is the vibrations, the motion/verb. So just like the search for the Higgs particle, it will alway be this quest for the ultimate form, yet reality isn’t just turtles all the way down, it’s layers of an onion and as one is peeling away, others are growing up under it. Time is not a static dimension. It is not noun. It is verb. It is process. Matter is not traveling along it from past events to future ones, it is moving about, in motion, verb, function. This creates form, which once created, is replaced by the next and fades into the past. Form goes from future to past. That’s why we see only the end coming.
This stagnation of form is a natural part of the process and when it gets too old to contain the energy within, it peels away, just as any concept that can no longer explain the information will be eventually replaced by the next stage/layer, as its proponents grow old and cannot answer the questions that keep coming up.
You are born into one world and spend your life watching it die off and another grow up in its place.
Uh, the vibrations on the strings in string theory are a fundamental aspect of the theory. You’ve heard of the different types of string theory, I presume? See the Wikipedia article on string theory for a cursory description if you haven’t:
http://en.wikipedia.org/wiki/String_theory#Dualities
The differences between these different types of string theory are the types of vibrations that exist.
And, by the way, if you don’t think there’s any expansion, how, pray tell, do you explain the finite age of our region of the universe?
Jason,
I’m certainly not accusing physics of not recognizing motion, just of trying to explain it away. Such as describing time as a dimension, where all events exist equally and the present is as subjective as a point in space.
The relationship between strings and vibrations does provide another example of my observation that there are two directions of time, in that while these strings go from past vibrations to future ones, the vibrations go from being in the future to being in the past.
Also; I didn’t say there is no expansion. I said it’s balanced by contraction, so light, that is not otherwise interrupted, travels about 13.7 billion lightyears before it’s so redshifted that the source appears to be receding at the speed of light. Since visible light can’t travel any further, it creates a horizon line. That’s why, in all directions we look, it appears that everything is emerging from an explosion of light.
I also made the observation that the radiation does still expand/move, just not at a visible wavelength and it’s coming from all directions, providing a black body CMBR.
I don’t know how to say this, but radiation leaving galaxies don’t contribute much in the way of gravitation. In other words you are just plain wrong on this. I and others have given a number of developed arguments for why this is so, but we seem to keep coming around to the same thing.
Lawrence B. Crowell
Lawrence,
Is that gravitation as all forms of curvature, or only that curving into gravitational objects, because my point is that radiation would cause the opposite effect, not an inward, but an outward, expanding curvature and at a very imperceptible level, given the amount of distance required for it to become measurable.
As mass collapses, radiation expands. While collapse prevails in density, expansion prevails in volume.
Keeping in mind that radiation is the one aspect of fundamental reality that does escape gravitational attraction. As Jason pointed out, space is inseparable from the material and energy in it, so since gravity is defined by mass falling into it, what does that say about the energy escaping from gravitational fields?
The radial expansion of radiation is not a causal agent for the expansion of the universe. You need to get this erroneous “barnacle” removed from you mind. It is just plain wrong. I wrote a couple of weeks ago on how the electromagnetic field couples to spacetime. Photons radiating from a source, such as a star, have far too small a mass-energy density to contribute to spacetime curvature in any significant way.
Black holes can in principle form without the emission of electromagnetic radiation. A whole gaggle of masses, say black dwarf stars, in a gravitationally bound cluster could by a statistically improbable evolution have their trajectories bring them at one time into a small region r
For some reason this did not all get sent:
small region r
a small region r less than 2GM/c^2. This would collapse the cloud of masses into a black hole without the radiation of many photons. Black holes can collide and form larger black holes and so forth.
It is also worth noting that a source of radiation which emits a pulse inside a black hole will not emit them into the distant universe. The null geodesics of the photons will be inward to the singularity. Remember, a black hole is defined in an elementary way as a gravity field from which light can’t escape.
Lawrence B. Crowell
Lawrence,
The point of my argument is that the universe isn’t expanding, so no, the expansion of radiation would be far too minor a force to cause all the galaxies and matter etc. to be flying away from each other at the rates proposed. What I’m arguing is that it effectively expands the space crossed by radiation, since it is only radiation that crosses the immense spaces involved. Sort of like climbing the down escalator doesn’t cause the floors to move further apart, even though it might seem that way, because the extra steps are falling into the gravity wells scattered around space.
Weight is a function of gravitational attraction, so is it theoretically possible that light is not only weightless, but “anti-weight,” ie. gravitationally repulsive?Obviously in a strong gravity field, this effect would be overwhelmed, so light is pulled in by gravity, but not to the extent massive particles are.
As for black holes and their effect on radiation, there are a lot of speculative theories and certainly gravity can accumulate mass and build up a store of energy, without losing it at an equivalent rate, but for practical purposes this energy is stored, not lost to some other dimension. I’ve read the primary black holes, those at the center of galaxies, don’t actually consume much matter when they are stable, so it would seem they function much like the eye of a storm, so most of the real activity is the donut around the center.
Safe to say, the variety of interactions across space is every bit as complex, if not far more so, then the variety of effects we see on earth. They will keep us guessing as long as humanity exists.
And yet you haven’t explained how the implied infinite age of a non-expanding universe would allow us to exist at all. So, why don’t you do that? Why does anything exist if the universe isn’t expanding?
I am aware that you have this idea of expansion vs contraction and that the universe is static or stationary. Look it is simply wrong. A problem is that this is starting to have similarities with arguing with creationists. In such arguments no matter what you present or argue to support evolution the creationist almost never changes their mind. Debates over global warming are taking on a similar characteristic, and anti-global warming advocates and creationists have big dollars behind them, which makes it particularly hard to argue with them in a final or convincing manner. In the case of cosmology there does not exist the big dollar organizations promoting alt-science stuff, though there are some small nascent groups with a small religious backing, such as geocenterists. In your case you are just an individual who has a quirky idea about things, but you appear unable to admit your error.
I understand that what you think has some internal logic in your mind, but the problem is that it is just wrong. What you think is not how the universe actually works. A whole lot of theories written by the most educated people and at top universities have been falisified as well. In most of these cases people admit they are wrong and go to work on other problems.
The following might be worth bearing in mind:
“The hardest part about gaining any new idea is sweeping out the false idea occupying that niche. As long as that niche is occupied, evidence and proof and logical demonstration get nowhere. But once the niche is emptied of the wrong idea that has been filling it — once you can honestly say, “I don’t know”, then it becomes possible to get at the truth.” R.A. Heinlein
Lawrence B. Crowell
Jason,
Why does life require a finite universe? Currently physics and cosmology try getting around various inconsistancies by proposing multiple universes. Why is an infinite universe less reasonable then that?
Lawrence,
I’m trying to figure how you have managed to lump me in with monotheistic fundamentalists. I’m not even a Platoist. As I recall, Big Bang Theory was originally proposed by a Catholic priest, Georges Lemaitre, trying to provide cosmological support for Genesis.
I realize I probably keep these ideas around out of stupidity, but not hardheadness. If someone could explain, in terms that make sense to me, why I’m wrong, I would certainly follow the more sensible route. As it is, physics currently prides itself that it’s “not intuitive,” ie. doesn’t make sense.
Don’t worry about me, though. I’m not trying to climb up the Ivory Tower. Just offering some commentary. The real weak link isn’t that current theories are about to be overthrown, but that the imminent implosion of the monetary bubble will likely strangle funding for research that doesn’t promise immediate realworld returns.
Sorry to test your patience. It has been an interesting discussion, at least for me.
The problem is entropy. I don’t really need to explain the second law of thermodynamics to you, do I?
Jason,
So this low entropy state just sprang into existance with the singularity and we are not supposed to look behind that curtain. That would be like questioning, uh…God!
I have no fear that Big Bang Theory is going anywhere anytime soon, because the basic premises on which it is based go back to the roots of western civilization. We would literally have to throw out the Bible, go back to before the time the Greeks were seduced by monotheism and reopen the debate between Plato and Aristotle. The absolute isn’t one, it’s zero. It’s not an ideal from which we fell, but the essence out of which we rise. It’s not the singularity, but the vacuum. Not the dimensionless point, but empty space. That an incredibly complex mathematics has been developed to support it, isn’t proof it’s right. Remember epi-cycles?
Time is not a linear dimension from start to finish, Genesis to Armageddon, birth to death, prologue to epilogue. It’s a cycle. Expansion, contraction. Mass/order collapses. Energy expands. Order falls away into the past, as energy moves into the future.
The origin of entropy in the universe I think comes from the self-squeezing of the vacuum state for gravitation. This is where the uncertainty in one quantum observable is reduced to near zero while the uncertainty in the other is expanded to near infinity. This is a trick common in quantum optics with the parametric amplification of a photon into two entangled photons. Sapphire has this effect on photons, which is used in various quantum experiments. There is an entropy measure associated with this in a coarse grained sense. The quantum gravity vacuum may well have this property.
Lemaitre did not propose the big bang as a support for Genesis. In fact he admonished Pope Pius XII not to encorporate this into an infallibility doctrine supporting the Church’s theology on creation. Lemaitre was working as an honest theoretical physicist, and said the origin of the big bang was something similar to the radioactive decay of an atom. Replace atom with an unstable vacuum configuration and this statement was not too far off the mark.
Back to the origin of entropy. The conformal group su(4) ~ so(4,2) contains the deSitter (dS) and Anti-deSitter (AdS) group. The AdS exists in a five dimensional space with two timelike directions, and as a result it has cyclic timelike solutions. So one selects out a patch with a pi cycle on the timelike directions. The conformal infinity of this is a Minkowski spacetime. The rub with this is that no amount of data on a spatial surface in AdS can uniquely give this conformal infinity. So additional data or boundary conditions are needed. I think this additional data is given by black holes and their brane dual as condensates of gauge fields, similar to the quark-gluon plasmas being probed at RHIC. This determines the cosmological constant / = /_0 + k*F^{ab}F_{ab}, where phi is the dilaton field with a quartic potential, k = constant, and F^{ab} a Yang-Mills field tensor. This data then provides the conformal completeness of the S subset AdS, or S = pi-cycle patch.
The initial state of the universe consisted of some set of unitarily inequivalent vacua, which under a coarse graining define an entropy to spacetime. This initial entropy was low, where by initial I mean during the inflationary period. The entropy increases until the cosmos expands as time “goes to” infinity to a deSitter space with the cosmological constant / and horizon radius r = sqrt{3/ /}. Hawking-Gibbon radiation will cause this to decay, similar to the emission of radiation from black holes, so that / approaches zero value and the spacetime is a flat Minkowski spacetime with nothing. This matches the dS with the AdS at conformal infinity, is a state with a single vacuum, but at maximal entropy. I think that how the universe started out with minimal entropy and with the structure of elementary particles we observe is in order to give this conformal completeness on AdS, and further to define the conformal group su(4) with a single vacuum states “at infinity.”
In spite of the 13.7 billion year age of the universe it is an infant compared to the time left in the future, which is infinite or “nearly so.” Things are going to get cold and dark and eventually everything will fade into nothingness and a complete void defined by a Minkowski spacetime. This is the endpoint of the Feynman path integral of the universe, while the initial state with a set of inequivalent set of vacua is the initial point. The path integral has a finite meaning when the conformal infinity is “mapped” to a finite value.
Lawrence B. Crowell
Lawrence,
Pardon my conceptual immaturity, but I see the difference between a primordial atom and unstable vacuum, as that between a dimensionless point and unstable, but otherwise featureless, space. In other words, is the initial state bound up in a single point, from which everything grew/expanded, or does it rise from an infinite, unstable vacuum?
Since this unstable vacuum would have to expand, otherwise it wouldn’t be unstable, the reaction is that at a certain level, it collapses and this effect builds on itself, creating ever larger regions of collapse. They then reach a state of density caused by this collapse not efficiently neutralizing the instability and bouncing back out as radiation. This radiation further destablizes the vacuum, causing it to continue expanding and so on….
I am using a different notion of the vacuum. It is the “no particle state” for a quantum field usually expanded in harmonic oscillator modes. There are operators a^* and a, where the ^* means complex conjugate and transpose the matrix. These act on states with n particles as
a|n) = sqrt{n}|n-1) —> reduces the number of particles
and
a^*|n) = sqrt{n+1}|n+1).
The Hamiltonian or energy operator turns out to be
H = hbar-freq(a^*a + 1/2).
These operators are derived from the form of the classical Hamitlonian for the harmonic oscillator, such as a spring of a pendulum with small oscillations. This Hamiltonian operator then acts on a state |n) as
H|n> = hbar-freq(n + 1/2)|n),
and there is this energy for the vacuum state |0). This is sometimes called the zero point energy (ZPE), which is an artifact of quantization. It can be removed by various techniques.
There is a lot of nonsense about the ZPE, such as people who think it is a source of free energy. But anyway this is what I was meaning by the vacuum state. In the case I wrote this morning I am referring to a vacuum state associated with a quantum wave function(al) for a metric spacetime configuration variable. A vacuum for this state means the spacetime in a sense does not exist.
BTW, normally the state vector is written with the horizontal carrot instead of a paranthesis, but this system seems to not like them.
Lawrence B. Crowell
So it’s only particles and oscillations?
If there is no ZPE, what is “dark energy” in the context of an expanding universe?
I can only describe this right now. The Hamiltonian for the Harmonic oscillator is
H = 1/2(p^2 + f^2q^2)
where p is the momentum, q the position, f the frequency, and the mass term has been absorbed in these. Now if I add a term i(qp – pq) [i = sqrt{-1}] classically by commutivity this is zero. Yet if I write the momentum and position variables in quantum operator form this commutator is not zero. The hamiltonian for the Harmonic osciilator is
H = hbar-f/2(a^*a + aa^*) = hbar-f(a^*a + 1/2)
where I have added a^*a – a^*a = 0 and this gives a commutator
[a, a^*] = aa^* – a^*a = 1.
Now if I do this quantization on the classical level with the zero commutator added in with the classical variables
[p, q] = pq- qp = 0
and then quantized I can eliminate the ZPE term hbar-f/2. Classical mechanics has commutivity of variables, but when quantized that commutivity is lost, such as [q, p] = i hbar.
A common way of doing this is something called normal ordering. This is somewhat justified by the fact there is no classical content to the ZPE. This is what I have just argued for. The traditional approach to the cosmological constant is to take a ZPE vacuum energy and construct the cosmological constant from a momentum-energy tensor constructed from ZPE terms. This causes all sorts of problems. A straight ZPE constructed this way predicts a cosmological constant 123 orders of magnitude larger than what is observed. Other horrors rear their head, and in a way they are related to this problem of the “dark misleading force.”
The cosmological constant is due to an inherent curvature to spacetime. It is not due to a source, such as a “dark misleading force.” Yet if we pause for a minute we might think of a ZPE energy as having a mass-energy content and that this is something which could couple to a spacetime manifold. So is this inherent curvature induced by the cosmological constant related in some way to a quantum ZPE? Probably, but not quite in the naive way we do this. To work on this involves walking through a minefield. Huge amounts of confusion lies here, such as ideas that virtual loops and the like are some real aspect of the vacuum and so forth. Yet this does indicate some subtle connection between general relativity and quantum field theory. Yet I think this connection is far more subtle than what is thought by most.
Lawrence B. Crowell
Lawrence,
Presumably an opposite curvature then that commonly associated with gravity. Sort of like a hill is the opposite of a valley?
So you don’t think there is any possibility that radiation can have the effect of curving space, as recorded by light, such as redshifting it, without having equal effect on the position of emitting objects? I should point out that light passing through a gravity field is curved, but that doesn’t mean the source is moved by this effect. At least there would be no need for ZPE, or dark energy, to explain why space appears to expand, if this is a possibility.
The recent posting by Sean, on the article by Dennis Overbye about Boltzmann brains, is a pretty graphic example of the problems cosmology is having in trying to fit together all the current concepts that are considered resolved. Do you think the answers will suddenly become clear, or is cosmology headed down the path of becoming a scientific laughingstock?
Please, you have to abandon this idea about a competing expansion of space due to radiation balancing a contraction by gravity. It is just wrong. A number of posters here have indicated by various means why this is the case.
I think in the next couple of decades some work with deep space astronomy and some new particle physics experiments is going to lead to data supporting an emergent theory of quantum gravity and cosmology. What does emerge might be different from what is now thought. We will just have to see how things develop.
Lawrence B. Crowell
Lawrence,
Thanks for the time and effort.
Regards,
JBMjr.