The beginning of everything: A new paradigm shift for the infant universe

Nov 29, 2012 by Barbara K. Kennedy
The power spectrum in the cosmic microwave background (CMB) predicted in Loop Quantum Cosmology and in the Standard Inflationary Scenario are contrasted in this plot, which shows their ratio as a function of k, the inverse of wave length, of fluctuations in the CMB. For many of the parameters, observable wave numbers k are greater than 9 and the two predictions are indistinguishable. For a narrow window of parameters, observable k can be smaller than 9. Then the two predictions differ. Both are in agreement with currently available data, but future observations should be able to distinguish between them. Credit: Ashtekar lab, Penn State University

(Phys.org)—A new paradigm for understanding the earliest eras in the history of the universe has been developed by scientists at Penn State University. Using techniques from an area of modern physics called loop quantum cosmology, developed at Penn State, the scientists now have extended analyses that include quantum physics farther back in time than ever before—all the way to the beginning. The new paradigm of loop quantum origins shows, for the first time, that the large-scale structures we now see in the universe evolved from fundamental fluctuations in the essential quantum nature of "space-time," which existed even at the very beginning of the universe over 14 billion years ago. The achievement also provides new opportunities for testing competing theories of modern cosmology against breakthrough observations expected from next-generation telescopes. The research will be published on 11 December 2012 as an "Editor's Suggestion" paper in the scientific journal Physical Review Letters.

"We humans always have yearned to understand more about the origin and evolution of our ," said Abhay Ashtekar, the senior author of the paper. "So it is an exciting time in our group right now, as we begin using our new paradigm to understand, in more detail, the dynamics that matter and geometry experienced during the earliest eras of the universe, including at the very beginning." Ashtekar is the Holder of the Eberly Family Chair in Physics at Penn State and the director of the university's Institute for and the Cosmos. Coauthors of the paper, along with Ashtekar, are postdoctoral fellows Ivan Agullo and William Nelson.

The new paradigm provides a conceptual and for describing the exotic "quantum-mechanical geometry of space-time" in the very . The paradigm shows that, during this early era, the universe was compressed to such unimaginable densities that its behavior was ruled not by the classical physics of Einstein's general theory of relativity, but by an even more fundamental theory that also incorporates the strange dynamics of quantum mechanics. The density of matter was huge then—1094 grams per cubic centimeter, as compared with the density of an atomic nucleus today, which is only 1014 grams.

In this bizarre quantum-mechanical environment—where one can speak only of probabilities of events rather than certainties—physical properties naturally would be vastly different from the way we experience them today. Among these differences, Ashtekar said, are the concept of "time," as well as the changing dynamics of various systems over time as they experience the fabric of quantum geometry itself.

No space observatories have been able to detect anything as long ago and far away as the very early eras of the universe described by the new paradigm. But a few observatories have come close. Cosmic background radiation has been detected in an era when the universe was only 380-thousand years old. By that time, after a period of rapid expansion called "inflation," the universe had burst out into a much-diluted version of its earlier super-compressed self. At the beginning of inflation, the density of the universe was a trillion times less than during its infancy, so quantum factors now are much less important in ruling the large-scale dynamics of matter and geometry.

Observations of the cosmic background radiation show that the universe had a predominantly uniform consistency after inflation, except for a light sprinkling of some regions that were more dense and others that were less dense. The standard inflationary paradigm for describing the early universe, which uses the classical-physics equations of Einstein, treats space-time as a smooth continuum. "The inflationary paradigm enjoys remarkable success in explaining the observed features of the cosmic background radiation. Yet this model is incomplete. It retains the idea that the universe burst forth from nothing in a Big Bang, which naturally results from the inability of the paradigm's general-relativity physics to describe extreme quantum-mechanical situations," Agullo said. "One needs a quantum theory of gravity, like loop quantum cosmology, to go beyond Einstein in order to capture the true physics near the origin of the universe."

Earlier work with loop quantum cosmology in Ashtekar's group had updated the concept of the Big Bang with the intriguing concept of a Big Bounce, which allows the possibility that our universe emerged not from nothing but from a super-compressed mass of matter that previously may have had a history of its own.

Even though the quantum-mechanical conditions at the were vastly different from the conditions after inflation, the new achievement by the Penn State physicists reveals a surprising connection between the two different paradigms that describe these eras. When scientists use the inflation paradigm together with Einstein's equations to model the evolution of the seed-like areas sprinkled throughout the cosmic background radiation, they find that the irregularities serve as seeds that evolve over time into the galaxy clusters and other large-scale structures that we see in the universe today. Amazingly, when the Penn State scientists used their new loop-quantum-origins paradigm with its quantum-cosmology equations, they found that fundamental fluctuations in the very nature of space at the moment of the Big Bounce evolve to become the seed-like structures seen in the cosmic microwave background.

"Our new work shows that the initial conditions at the very beginning of the universe naturally lead to the large-scale structure of the universe that we observe today," Ashtekar said. "In human terms, it is like taking a snapshot of a baby right at birth and then being able to project from it an accurate profile of how that person will be at age 100."

"This paper pushes back the genesis of the cosmic structure of our universe from the inflationary epoch all the way to the Big Bounce, covering some 11 orders of magnitude in the density of matter and the curvature of space-time," Nelson said. "We now have narrowed down the initial conditions that could exist at the Big Bounce, plus we find that the evolution of those initial conditions agrees with observations of the cosmic background radiation."

The team's results also identify a narrower range of parameters for which the new paradigm predicts novel effects, distinguishing it from standard inflation. Ashtekar said, "It is exciting that we soon may be able to test different predictions from these two theories against future discoveries with next-generation observational missions. Such experiments will help us to continue gaining a deeper understanding of the very, very early universe."

Explore further: Do we live in a 2-D hologram? New Fermilab experiment will test the nature of the universe

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MrGrynch
2.5 / 5 (8) Nov 29, 2012
This is extremely promising in its ability to provide at least SOME ability to test new observations with theory. I feel that we are approaching a period of upheaval in our understanding of the cosmos and the fundamental interactions within it. Exciting times ahead.
arnold_townsend
4.4 / 5 (7) Nov 29, 2012
The article is missing exponent notation in "1014" and "1094" ... s/b 10^14 and 10^94 (or acceptable equivalent). Not a major issue but important.
Claudius
2 / 5 (4) Nov 29, 2012
"... the very nature of space..."

This seems a little vague.
jdbertron
1 / 5 (7) Nov 29, 2012
We publish trailers to abstracts of scientific papers now ?

Publish rubbish or perish.
TheGhostofOtto1923
3.9 / 5 (18) Nov 29, 2012
We publish trailers to abstracts of scientific papers now ?

Publish rubbish or perish.
"Phys.org internet news portal provides the latest news on science including: Physics, Space Science, Earth Science, Health and Medicine."

-Along with links and refs for those not too lazy to use them.

"A web portal is a web site that brings information from diverse sources in a unified way."

-If you dont like the format perhaps youd like to try somewhere else?
CrossMan
5 / 5 (2) Nov 29, 2012
arXiv ref: 1209.1609
Terryg81
1.8 / 5 (5) Nov 29, 2012
"Earlier work with loop quantum cosmology in Ashtekar's group had updated the concept of the Big Bang with the intriguing concept of a Big Bounce, which allows the possibility that our universe emerged not from nothing but from a super-compressed mass of matter that previously may have had a history of its own."

This idea of a "Big Bounce" instead of a "Big Bang" is almost funny. The thought that you can just push the problem of space and time from nothing back into some "super compressed mass of matter" which would have had to come from??? Nothing.

To be rational and logical one must say that nothing produces nothing and try and tackle the problem instead of sidestepping it.
Urgelt
5 / 5 (3) Nov 29, 2012
Well, it's an interesting approach.

We still don't know, however, if space-time is divided into quanta. A theory that supposes that it is may be on thin ice.

Need evidence. Lots of evidence.
Shadhavar
4.4 / 5 (7) Nov 29, 2012
@Terryg81 the notion that everything must have a beginning is a human logical fallacy. "Nothing" is also an invalid human construct.
IronhorseA
1 / 5 (7) Nov 29, 2012
@Terryg81 the notion that everything must have a beginning is a human logical fallacy. "Nothing" is also an invalid human construct.


Even things which are cyclic have a beginning,ie. the very first cycle. Infinite pasts create the same 'existence' issues that religion does and from a scientific point of view are best avoided barring observable phenomena pointing in that direction.
Shadhavar
5 / 5 (6) Nov 29, 2012
Even things which are cyclic have a beginning,ie. the very first cycle. Infinite pasts create the same 'existence' issues that religion does and from a scientific point of view are best avoided barring observable phenomena pointing in that direction.


That is exactly the fallacy of which I spoke.
jsdarkdestruction
4 / 5 (8) Nov 30, 2012
"which allows the possibility that our universe emerged not from nothing but from a super-compressed mass of matter that previously may have had a history of its own."
the big bang allows the very same possibility. nowhere does a cyclic universe confict with the big bang. ours could be one of many collapses and bangs. the big bang theory deals with our current bang. that is all.
otherwise, interesting article.
vacuum-mechanics
1.3 / 5 (8) Nov 30, 2012
"This paper pushes back the genesis of the cosmic structure of our universe from the inflationary epoch all the way to the Big Bounce, covering some 11 orders of magnitude in the density of matter and the curvature of space-time," Nelson said. "We now have narrowed down the initial conditions that could exist at the Big Bounce, plus we find that the evolution of those initial conditions agrees with observations of the cosmic background radiation."

This seems be a better theory, anyway whether it is a big bang or big bounce, the crucial problem is that where is the huge density of matter come from? May be one physical idea with no such mentioned problem, here, could give the answer.
http://www.vacuum...=7〈=en
Torbjorn_Larsson_OM
5 / 5 (2) Dec 01, 2012
Four immediate problems:

- Standard inflationary cosmology do not "retains the idea that the universe burst forth from nothing in a Big Bang". The ground state of inflation is eternal inflation, because nearly all inflation potentials naturally results in it.

- "Loop quantum cosmology" lacks a physical basis. It has never managed to show a lowest potential so no energy, and even less a harmonic oscillator so no dynamics.

- "Bounces" are what I know nowadays prohibited by some fancy theoretical physics. IIRC see Penrose.

- Spacetime appears smooth below Planck length scales as probed by cosmological photon timing.

By the way, in inflation of any kind it is better to define "Big Bang" as the first moment we can observe particles with a thermodynamically defined temperature. In standard cosmology that is, contrary to classical Big Bang theories, far from Planck temperatures.
Torbjorn_Larsson_OM
5 / 5 (1) Dec 01, 2012
@ MrGrynch: Your feelings and a dollar gives you a coffee @ Starbucks.

@ TGO: I would have to agree with jdbertron. A science news portal is not a generic web portal. Science papers are peer reviewed, and they have no "rubbish" stamp.

@ Terryg81: Physics notions of "nothing" are causal. But as for cosmology, you don't specifically need spacetime to appear causally out of such "nothing" lack of it. Inflation looks good so far.

@ vacuum-mechanics: Your "crucial problem" hasn't been a problem for decades. When inflation ends, the vacuum energy will cool off by making particles thermally.

"When inflation ends the temperature returns to the pre-inflationary temperature; this is called reheating or thermalization because the large potential energy of the inflaton field decays into particles and fills the universe with Standard Model particles, including electromagnetic radiation, starting the radiation dominated phase of the Universe. [ http://en.wikiped...y_theory
]
ROBTHEGOB
2 / 5 (4) Dec 03, 2012
You are all delusional; there is no beginning nor ending of space or time. You have been misled by your very limited perceptions and assumptions of the physical universe.
rubberman
1 / 5 (2) Dec 03, 2012
You are all delusional; there is no beginning nor ending of space or time. You have been misled by your very limited perceptions and assumptions of the physical universe.


I can't believe I am forced to agree with RTG....for the most part. Time is a human construct. The universe is an arena of undetermined size inside which energy continuously changes states, there is no T = 0 (where "T" is time). I would think that once we understand the structure today, how it was X amount of years ago will be alot easier to determine.
ValeriaT
1 / 5 (2) Dec 03, 2012
If you try to imagine, what would you see with observation of the water surface with its own waves, then you'll realize soon, that the surface ripples scatter into longitudinal ones at distance in similar way, like at the short distance scale. This model leads into geometric similarity of Higgs boson field with dark matter field: they both follow the nested dodecahedron geometry of particle packing, similar to foam. It doesn't imply, that the Universe exploded from dense state - it just illustrates the similarity of scattering of light with quantum fluctuations of vacuum at both quantum, both cosmic scale. This similarity was already demonstrated mathematically in five dimensions as so-called AdS/CFT correspondence for some quantum gravity theories, including string theory.
VendicarD
not rated yet Dec 04, 2012
Set your energy zero point in the right place and you have some positive energy for mass, some negative energy for the vacuum and both sum to zero.

Where the energy comes from is a question that just goes away. It has always been zero.

"the crucial problem is that where is the huge density of matter come from?" - VM
Job001
1 / 5 (1) Dec 05, 2012
Why not stand on the shoulders of science giants and plot this as logarithmic inverse wavelength since it's about exponential energy relationships anyway. Then the relationship would be more normal and comprehensible. See Planck's law, Boltzmann distribution, etc.
http://en.wikiped...%27s_law