International team strengthens Big Bang Theory

Jun 06, 2013
The image illustrates the detailed modelling of a small piece of the surface of an old metal-poor star used to derive its abundance of lithium-6. Credit: Karin Lind, Davide De Martin

(Phys.org) —An international team of scientists using the most powerful telescope on Earth has discovered the moments just after the Big Bang happened more like the theory predicts, eliminating a significant discrepancy that troubled physicists for two decades. The discovery will be published in the international journal Astronomy & Astrophysics on June 6.

One of the most important problems in physics and astronomy was the inconsistency between the lithium isotopes previously observed in the oldest stars in our galaxy, which suggested levels about two hundred times more Li-6 and about three to five time less Li-7 than nucleosynthesis predicts. This serious problem in our understanding of the early Universe has invoked exotic physics and fruitless searches for pre-galactic production sources to reconcile the differences.

The team, led by Karin Lind of the University of Cambridge, has proven the decades-old inventory relied on lower quality observational data with analysis using several simplifications that resulted in spurious detections of lithium isotopes.

Using observations of ancient stars with W. M. Keck Observatory's 10-meter telescope and state-of-the-art models of their atmospheres has shown that there is no conflict between their lithium-6 and lithium-7 content and predictions of the standard theory of Big Bang nucleosynthesis, restoring thus the order in our theory of the early universe.

The discovery that the universe was expanding by Edwin Hubble in the 1920s and subsequent observations suggest the universe began about 13.8 billion years ago in an event called the Big Bang. The fundamental observations that corroborate the Big Bang are the cosmic microwave radiation and the chemical abundances of the light elements described in the Big Bang nucleosynthesis theory.

"The predictions of Big Bang nucleosynthesis have been one of the main successes of the standard Big Bang model," said lead author Lind. "Our findings remove much of the stark tension between 6Li and 7Li abundances in stars and standard BBN, even opening up the door for a full reconciliation. This further consolidates a model resting heavily on the pillars of the cosmic microwave background and the expanding Universe."

Taking accurate measurements of lithium-6 and lithium-7 in old stars is extremely challenging, both from a theoretical and observational perspective, in particular for lithium-6, because being the less abundant isotope of lithium, its signature is very weak. The required data can only be obtained with the largest telescopes on such as the Keck Observatory on the summit of Mauna Kea, Hawaii equipped with the powerful High Resolution Echelle Spectrometer (HIRES) spectrograph to disperse the stellar light into its constituent colors and absorption features.

"Back in 2004 HIRES was upgraded with CCDs having smaller pixels, allowing to see finer details in the spectrum," University of Sao Paulo's Jorge Meléndez said. "A high spectral resolution provided by HIRES is needed to study with exquisite detail the line profile and to estimate the presence of Lithium-6. The large light-collecting power of Keck Observatory allowed us to observe stars with a more 'pristine' composition than any previous study."

Even with the mighty Keck I , a single star must be observed for several hours to gather enough photons for a detailed observation. The modeling of such data is also very demanding, as different processes in the atmospheres of such metal-deficient old stars may mimic the presence of -6. The data must be analyzed using sophisticated model atmospheres created by the team in 3D and included complex calculations that run for weeks on powerful super computers.

"We simultaneously relaxed two key physical assumptions in the modeling of stellar atmospheres; one-dimensional hydrostatic and local thermodynamic equilibrium," Lind said. "Using more sophisticated physics and powerful super-computers, we managed to remove the systematic biases that plague traditional modeling and have previously led to false identifications of the 6Li/7Li isotopic signature."

The synergy of high quality Keck observations and detailed theoretical modeling has solved cosmological problems that haunted particle and astrophysicists during the last two decades.

"Understanding the birth of our Universe is pivotal for the understanding of the later formation of all its constituents, ourselves included," Lind said. "The Big Bang model sets the initial conditions for structure formation and explains our presence in an expanding universe dominated by dark matter and energy."

The now rests on more firm footing.

Explore further: A new approach in the search for extraterrestrial intelligence: targeting alien polluters

More information: Lind, K. et al. The lithium isotopic ratio in very metal-poor stars, Astronomy & Astrophysics. dx.doi.org/10.1051/0004-6361/201321406

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foolspoo
1.6 / 5 (19) Jun 06, 2013
The discovery that the universe was expanding by Edwin Hubble in the 1920s and subsequent observations suggest the universe began about 13.8 billion years ago in an event called the Big Bang

that is still very presumptuous. this could be the 9384th cycle of this universe
Sinister1811
2.6 / 5 (12) Jun 06, 2013
International team strengthens Big Bang Theory


It's about time they made some new episodes. ;)
RichTheEngineer
3.3 / 5 (7) Jun 06, 2013
Damn, and I was thinking that new, international, writers were hired for the TV show.
jsdarkdestruction
4.2 / 5 (10) Jun 06, 2013
The discovery that the universe was expanding by Edwin Hubble in the 1920s and subsequent observations suggest the universe began about 13.8 billion years ago in an event called the Big Bang

that is still very presumptuous. this could be the 9384th cycle of this universe

the big bang theory doesn't say it isn't. it doesn't address it at all. it just concerns this current bang.
Fleetfoot
4.1 / 5 (9) Jun 06, 2013
this could be the 9384th cycle of this universe


It could be but it would then probably be the last. This version is accelerating towards a de Sitter solution which gives permanent expansion, there will be no big crunch this time to restart another bang.
Benni
1.2 / 5 (13) Jun 06, 2013
this could be the 9384th cycle of this universe


It could be but it would then probably be the last. This version is accelerating towards a de Sitter solution which gives permanent expansion, there will be no big crunch this time to restart another bang.


Not a chance. Expansion can't be "permanent" because that requires a space of infinity & entropy cannot function inside such an environment.

It may not be cycle 9384 but whatever cycle number it is (and it does have a number), it's all due to the limitation entropy imposes on energy generation systems, and that is what the Universe is, one big energy generation system.
LarryD
3.7 / 5 (6) Jun 06, 2013
So all this research, all our gained knowledge, all our efforts, all our arguments together, all our yesterdays...is just going to end in the obliteration of the universe in the next crunch? You sure know how to make a grown (old) man cry. Do you think there will be another 'Newton', Maxwell, Einstein next time around? Maybe I should stop reading science and go back to Marvel Comics, Dandy and Beano.....
ROBTHEGOB
1.5 / 5 (19) Jun 07, 2013
The Big Bang is a fantasy. There is no beginning, and no end. Hard for us to comprehend, but that is the way it is. Not that it really matters to us anyway, really. But it makes for fun arguments.
shavera
3.8 / 5 (6) Jun 07, 2013
Not a chance. Expansion can't be "permanent" because that requires a space of infinity & entropy cannot function inside such an environment.


The best data we have suggests that the universe already is infinite in spatial dimension. And entropy calculations work just fine in such an environment. Could you elaborate further on exactly why you believe entropy "cannot function" in an infinite space?
Oversoul 1
1.4 / 5 (5) Jun 07, 2013
@Benni:
"Expansion can't be "permanent" because that requires a space of infinity"

Who said that the space is finite (for sure)? They came from there... aliens :D
It's simple: (i recently learnt mathematical induction :)
1. we have something: o, and it is (has to be) in something: [o]
2. [o] -> this is again in something: [[o]]
now repeat 2. a lot, then sum: OO (this intrinsically reprezents infinity and the worth of the sum of my comments as double zero)

@ROBTHEGOB:
"There is no beginning, and no end."

I hope you are right, and death is something like "waking up"...

@LarryD:

"So all this research, all our gained knowledge, all our efforts, all our arguments together, all our yesterdays..."

changes...

And if finally turns out that is the way the universe works, than that is...
And you cry because you built up too strong emotional bond with ideas which will not hold (maybe):
Unrequited love... i know... :'(
But next time you have a new chance to be Einsten, if you want...
alfie_null
5 / 5 (3) Jun 07, 2013
Hard for us to comprehend, but that is the way it is.

Speaking only of yourself, of course.
Aliensarethere
3.2 / 5 (5) Jun 07, 2013
this could be the 9384th cycle of this universe


It could be but it would then probably be the last. This version is accelerating towards a de Sitter solution which gives permanent expansion, there will be no big crunch this time to restart another bang.


We don't know what causes the expansion to accelerate, so whatever it is, it could stop at any time, and we are back to the big crunch scenario.
thingumbobesquire
1 / 5 (2) Jun 07, 2013
"The Big Bang model sets the initial conditions for structure formation and explains our presence in an expanding universe dominated by dark matter and energy."

Really? Since no one has explained "dark energy," how could the Big Bang explain "our presence in it?"
shavera
5 / 5 (2) Jun 07, 2013
well it explains how the universe evolves even when it has components of mass and energy that aren't described by our present understanding of particle physics. General Relativity is perfectly fine with additional mass and energy terms that aren't accounted for in the Standard Model. All it means is that we don't know everything yet, a statement I'm sure will shock no one.
Fleetfoot
4 / 5 (4) Jun 07, 2013
this could be the 9384th cycle of this universe


It could be but it would then probably be the last. This version is accelerating towards a de Sitter solution which gives permanent expansion, there will be no big crunch this time to restart another bang.


Not a chance. Expansion can't be "permanent" because that requires a space of infinity & entropy cannot function inside such an environment.


Entropy works just fine, the expansion is adiabatic.

that is what the Universe is, one big energy generation system.


Nope, if it is closed, the Hamiltonian is always identically zero, energy is conserved. See the physics FAQ.
Fleetfoot
4 / 5 (4) Jun 07, 2013
We don't know what causes the expansion to accelerate, so whatever it is, it could stop at any time, and we are back to the big crunch scenario.


True but WMAP and Planck and other tests have shown no deviation from dark energy being accurately modelled by a cosmological constant. If it really is constant, the expansion will be asymptotic to an exponential in the future.
Fleetfoot
4 / 5 (4) Jun 07, 2013
"The Big Bang model sets the initial conditions for structure formation and explains our presence in an expanding universe dominated by dark matter and energy."

Really? Since no one has explained "dark energy," how could the Big Bang explain "our presence in it?"


Dark energy has only become significant in the last few billion years and is only slightly affecting the large scale expansion. That's is why it was so hard to discover.
Fleetfoot
4.2 / 5 (5) Jun 07, 2013
So all this research, all our gained knowledge, all our efforts, all our arguments together, all our yesterdays...is just going to end in the obliteration of the universe in the next crunch?


Nope, there won't be a crunch. There might be some sort of new bang in the deSitter universe so you could have a cyclic structure that way though, we really don't know.

You sure know how to make a grown (old) man cry.


I'll leave that to the mathematician John Baez who has written a brief but accurate description of our best model for "the end":

http://math.ucr.e...end.html

Maybe I should stop reading science and go back to Marvel Comics, Dandy and Beano.....


Given the level of knowledge of the cranks in this group, you probably wouldn't notice much difference.
Torbjorn_Larsson_OM
4.4 / 5 (7) Jun 07, 2013
Actually the remaining tension hadn't been enough to reject big bang, since Planck released their first data.

The Planck team haven't yet released their polarization data as papers due to that they haven't removed all systematics yet. (I.e. when they run statistics test, the extracted data isn't yet self consistent.) But 2 polarization channels are cleared enough that graphs have been released, and the fitted model from the power spectrum alone is a perfect "fit" without further fitting. Cosmologist http://trenchesof...spot.de/ has an article with the images.

A non-big bang model couldn't predict the correlations (structures) in the polarization data even if it could mimic all the rest. So today big bang is an observation, out of CMB data alone nonetheless.

This is nice test, even though it was now the expected outcome.

@natello: It is not data fishing as they do a new test for one particular theory about data. Data fishing is trying one test often, a random outcome.
Torbjorn_Larsson_OM
5 / 5 (5) Jun 07, 2013
Re the discussion on cyclical universes, there is a new, seemingly working proposal by cosmologist Steinhardt, earlier an inflationary cosmologist. See his youtube "Inflationary cosmology on trial", http://www.youtub...ptIJS7kQ .

As Steinhardt explains it, the older proposals were found out to run into a singularity problem. As entropy increases, every cycle had to have a larger volume. Run such a cycle history backwards, and you run into the very problem you tried to avoid - a big bang!

Steinhardt's new brane scenario takes his ekpyrotic model and have the observed dark energy dilute the universe. He then claims the same volume, same branes, can cycle indefinitely.

My problem with his proposal is parsimony. If we run the best inflation model that would work against his model, which he doesn't do, it can give standard particle finetunings out of anthropic theory. His cosmology remembers previous history, so tend to retain finetunings. [tbctd]
Torbjorn_Larsson_OM
5 / 5 (4) Jun 07, 2013
[ctd] Ironically Steinhardt claims parsimony as a feature.

Anyway, it is fringe as of yet, people work on inflation after Planck, you don't see cyclic models anymore.

@Benni: QM degrees of freedom works over an infinite Hamiltonian space, so entropy would work there too. You are thinking of classical entropy, but the vacuum is quantum.

@RTG: As I mentioned in my first comment, today big bang is an observation. If you aren't on a science site to discuss accepted science, please go.

@Oversoul1: The universe looks perfectly flat. We don't know if it is just very large compared to the observable universe, or flat. But it is most parsimonious, in some ways, to predict it is flat.
Torbjorn_Larsson_OM
5 / 5 (5) Jun 07, 2013
@tgbbs: *Everyone* has predicted ("explained") dark energy from vacuum energy. Look for example on Susskind's youtube lectures on cosmology. No cosmologist has voiced concerns that Susskind, renowned for baryogenesis theory and string theory both, is teaching his students something erroneous. It is because those that disagree now has something to prove, against parsimony and consensus.

"The Big Bang model sets the initial conditions for structure formation and explains our presence in an expanding universe dominated by dark matter and energy."

Structure formation comes out of inflation, not older big bang models, as quantum fluctuations in the inflaton field that freezes and then are released as they come back into the event horizon as inflation stops.

The sentence describes how we have structures despite the universe being subjected to dark energy expansion, again exponential as under inflation but inherently fighting against structures as it pulls large ones apart.
ValeriaT
1.6 / 5 (7) Jun 07, 2013
The Big Bang is a fantasy. There is no beginning, and no end. Hard for us to comprehend, but that is the way it is.
Actually it's the simplest model which doesn't require any further reasoning in accordance to Occam's razor. Why the Universe should ever have some particular state across the whole Universe, including the zero state? The random state is way more natural. In AWT the most general and universal theory must keep the least number of ad-hoced postulates and assumptions possible. The assumption of Universe beginning or end is one of them. We can therefore get such a theory of everything simply with removal all ad-hoced postulates from it - and this is just the approach of Aether Wave Theory.
ValeriaT
1.5 / 5 (8) Jun 07, 2013
Just because the AWT is solely random, it doesn't enforce neither Big Bang model, neither steady state universe model. It considers sorta mixture of both: the universe is composed of gigantic density fluctuations and we just happened to evolve inside one of them. The red shift is interpreted with scattering of light with vacuum density fluctuations, but for example the CMBR anisotropy points to extrinsically inhomogeneous universe. The famous astronomer Lara Mersini considers the universe as a system gigantic quantum fluctuations, which emerge and disappear randomly, but in AWT the unparticle geometry is more fundamental. You can imagine it like the fractal landscape under the fog - its visibility scope will be always superposed with hyperbolic geometry, if we neglect all other details. The CMBR anisotropy and the "axis of evil" is the manifestation of this geometry.
ValeriaT
1 / 5 (4) Jun 08, 2013
A new cosmology successfully explains the accelerating expansion of the universe without dark energy; but only if the universe has no beginning and no end. In other words, No Big Bang.
ValeriaT
1 / 5 (5) Jun 08, 2013
If the Universe expands - as Big Bang theory suggests - shouldn't the more distant areas of Universe appear more dense (i.e. with smaller average distance between galaxies), than the more nearby ones? It would violate the isotropy of the Universe observed.

BTW Even Edwin Hubble, the founder of the red shift opposed the Big Bang theory in this trivial way. The devil is always in subtle, but undeniable details - as Galileo realized already before four hundred years with his order of Venus phases.
Anda
5 / 5 (1) Jun 08, 2013
Back to reading comments after a couple of months (just page 1).
As always, trolls, deniers, science-based commentarists and beings with a "superior and absolute knowledge" without any maths or facts like dear "Water Ripples" posting as always with different nicks in the same article, right valeria?
Funny...
ValeriaT
1 / 5 (4) Jun 08, 2013
It would be a mistake to consider, that the confirmation of Big Bang nucleosynthesis may serve as a an evidence for Big Bang model. The father of this nucleosyntheis was Fred Hoyle, who just gave the Big Bang theory its name - but not because he loved this theory so much. Actually he was most obstinate hater of Big Bang model instead. How is it possible after then, Hoyle's nucleosynthesis model is still used? Well, Hoyle simply applied it to steady state model, as he believed, that the elements are formed in explosions from "creation field" (which would correspond the dark matter as known today) which happen at various places of observable Universe from time to time.
Fleetfoot
5 / 5 (1) Jun 08, 2013
If the Universe expands - as Big Bang theory suggests - shouldn't the more distant areas of Universe appear more dense (i.e. with smaller average distance between galaxies), than the more nearby ones?


Yes and no. The galaxies were smaller and more numerous because they were merging into fewrer, larger ones. However, galaxies form only at the peaks of density variations and some hadn't become high enough to form galaxies yet. We see a combined curve which dips then rises. Overall it fits the model.

It would violate the isotropy of the Universe observed.


No, at that time, the statistics were the same everywhere. Today we some fewer but larger galaxies and the universe is still homogenous, the variation only falsifies the steady state model which requires it to be a flat line. See the graph in this article:

http://phys.org/n...ies.html
Fleetfoot
5 / 5 (2) Jun 08, 2013
Hoyle simply applied it to steady state model, as he believed, that the elements are formed in explosions from "creation field" (which would correspond the dark matter as known today) which happen at various places of observable Universe from time to time.


Hoyle's "creation field" would have produced matter at a uniform rate everywhere in the steady state model, not in explosions which would have been mini- big bangs. The trouble with that is that it would have produced particle of lower mass at a higher rate and had to obey the conservation laws so electron-positron pairs would have dominated over say proton- antiproton pair. Nuetrons and anti-neutrons couldn't have lasted long enough or been hot enough to produce helium either. They would all have annihilated anyway so it never worked. In the end Hoyle gave up and switched to QSSC which replaced the bang with a bounce, but that fails too, it happens too late.
ValeriaT
1 / 5 (6) Jun 08, 2013
The galaxies were smaller and more numerous because they were merging into fewer, larger ones
This just contradicts the observations, in which the (diameter of) older galaxies appear larger in average. There is still lotta space between these galaxies, which appear separated as well, as the contemporary galaxies with no signs of their merging. Dense aether model explains this observation with scattering of light, which leads into blurring of images of distant galaxies.

In addition we have so-called starlight problem, or starlight travel-time problem, which concerns the placement of stars at distances so far from Earth that starlight could not traverse that distance in less than the age of the universe. Yet the light has reached Earth anyway. This raises a question under Big Bang theory: how did this starlight reach Earth?
ValeriaT
1 / 5 (7) Jun 08, 2013
Hoyle's "creation field" would have produced matter at a uniform rate everywhere in the steady state model, not in explosions which would have been mini- big bangs
In dense aether model the dark matter is concentrating between galaxies, at the connection points of multiple galaxies in particular. It corresponds the Gregory-Laflame instability which we discussed here recently. It corresponds the steady state Universe model: the galaxies dissolve into photons and neutrinos via radiation of energy and they do condense back again from dark matter clouds (composed of photons and neutrinos) somewhere else. So if some matter or energy disappears from our sight at some place of observable Universe, then it's returned back again somewhere else behind our back.
not in explosions which would have been mini- big bangs
IMO these explosions correspond so called the quasars and they're observed all around us.
zz6549
not rated yet Jun 08, 2013
"Theory" in the title shouldn't be capitalized. http://blog.apast...ord.html
Fleetfoot
5 / 5 (2) Jun 09, 2013
"Theory" in the title shouldn't be capitalized. http://blog.apast...ord.html


It shouldn't even be "theory", it's a model based on the Friedmann Equations which are a solution of the theory known as General Relativity.
Fleetfoot
4.2 / 5 (5) Jun 09, 2013
The galaxies were smaller and more numerous because they were merging into fewer, larger ones
This just contradicts http://arxiv.org/...11.4956, in which the (diameter of) older galaxies appear larger in average.


That paper is about low redshifts, z<0.2, so not relevant.

Dense aether model explains this observation with scattering of light, which leads into blurring of images of distant galaxies.


We see point sources like quasars too though so we know there is no blurring or scattering.

This raises a question under Big Bang theory: how did this starlight reach Earth?


Very distant galaxies look bigger because they were closer to us when the light was emitted so they subtend a greater angle than those we see at later times. The minimum is at about z=1.64

The light is able to reach us because it has been traveling while the universe expanded. The red line shows its locus:

http://www.astro....htm#MSTD
ValeriaT
1 / 5 (6) Jun 09, 2013
That paper is about low redshifts, z<0.2, so not relevant.
I'm citing your comment "The galaxies were smaller and more numerous because they were merging into fewer, larger ones" - not a paper. After then it was just your comment, which wasn't relevant to that paper - don't you think?
We see point sources like quasars too though so we know there is no blurring or scattering
We don't observe the quasars like the point sources. Don't invent the stuffs instead of arguments.
The light is able to reach us because it has been traveling while the universe expanded
Yep, your source cites it as an "horizon problem". You should read more carefully your own links.
Fleetfoot
5 / 5 (2) Jun 09, 2013
That paper is about low redshifts, z<0.2, so not relevant.
I'm citing your comment "The galaxies were smaller and more numerous because they were merging into fewer, larger ones" - not a paper.


You asked:

If the Universe expands - as Big Bang theory suggests - shouldn't the more distant areas of Universe appear more dense


I tried to correct your lack of knowledge by explaining that there are several different effects involved. You are right that expansion means objects would have been closer in the past and mergers mean they were smaller but more numerous in the past, both of which reduce the spacing, but galaxies only form in the densest regions and that means there were fewer in the past as the dense regions took time to collapse which increases the spacing. What we observe is the combination of all of those and at high redshifts, the latter effect dominates but over shorter ranges, the spacing decreases. The paper you mentioned is on an unrelated topic.
Fleetfoot
5 / 5 (4) Jun 09, 2013
We don't observe the quasars like the http://cdn.physor...ersd.jpg


An image with no context is meaningless.

This raises a question under Big Bang theory: how did this starlight reach Earth?


The light is able to reach us because it has been traveling while the universe expanded

Yep, your source cites it as an "horizon problem".


Nope. The horizon problem is the question of why the temperature of the CMBR seen in opposite directions is so well matched, it has nothing to do with travel time.

You should read more carefully your own links.


I learned what is in Ned's tutorial more than a decade ago, it's time you started studying this beginner-level stuff if you want to follow these conversations.
GSwift7
2.7 / 5 (6) Jun 10, 2013
It could be but it would then probably be the last. This version is accelerating towards a de Sitter solution which gives permanent expansion, there will be no big crunch this time to restart another bang.


That assumes there aren't other mechanisms at work.

For example (warning, this is just me making something up): Quantum mechanics says there's a finite lower limit of energy states. Once you get down to a single quanta of something, it cannot be divided further. So, as the Universe expands it decreases in density. What happens if the average energy density of space, in a given region, reaches the lowest possible limit of density? Does it rebound back? Does that trigger a big bang at that location? Something even more bizzar, like an anti-black hole, or 'negative' space with negative energy, since quantum theory says it cannot be zero? Or does it just 'wink out'? Imagine the space between you and somewhere else just vanishing...
Modernmystic
1 / 5 (4) Jun 10, 2013
For example (warning, this is just me making something up): Quantum mechanics says there's a finite lower limit of energy states. Once you get down to a single quanta of something, it cannot be divided further. So, as the Universe expands it decreases in density. What happens if the average energy density of space, in a given region, reaches the lowest possible limit of density? Does it rebound back? Does that trigger a big bang at that location? Something even more bizzar, like an anti-black hole, or 'negative' space with negative energy, since quantum theory says it cannot be zero? Or does it just 'wink out'? Imagine the space between you and somewhere else just vanishing...


Agreed.

Furthermore, it may not be you "just making something up", or more accurately you many not be too far off the mark...

http://en.wikiped...e_vacuum
Fleetfoot
5 / 5 (1) Jun 10, 2013
.. there will be no big crunch this time to restart another bang.


That assumes there aren't other mechanisms at work.


True but tests for variation of the Cosmological Constant are null so far so it is currently the best observational result.

For example (warning, this is just me making something up): Quantum mechanics says there's a finite lower limit of energy states. Once you get down to a single quanta of something, it cannot be divided further. So, as the Universe expands it decreases in density.


The density is leveling off and will be asymptotic to a constant value given by dark energy. In fact you may have identified the nature of DE ;-)

See the graph on the last page of this:

http://www.nicadd...x_06.pdf
GSwift7
3 / 5 (6) Jun 10, 2013
Furthermore, it may not be you "just making something up", or more accurately you many not be too far off the mark...


The density is leveling off and will be asymptotic to a constant value given by dark energy. In fact you may have identified the nature of DE ;-)


Yeah, I wasn't 'exactly' making stuff up. It was more like an amature version of different stuff I've read, but all that kind of stuff is way speculative right now. There's a ton of different ways to interpret our best observations so far. I like to play around with different versions in my head and try to imagine what the implications might look like.

Talking about such things is fun, but borders on whimsical, and it's easy to go off the deep end into pure fantasy. Not to mention that there's very few people who can actually understand that level of theory.

Heck, a lot of professional physicicists don't get some of the high level stuff. It's hard to wrap your mind around such alien ideas.