iPhone app iPad app Android phone app Android tablet app More

Featuring fresh takes and real-time analysis from HuffPost's signature lineup of contributors
David Kaiser

GET UPDATES FROM David Kaiser
 

Elegant Wiggles: Why the Universe Is Lumpy

Posted: 05/22/2012 8:49 pm

Back in January the Edge (the website, not the guitarist) posted almost 200 short essays in response to the question, "What is your favorite deep, elegant, or beautiful explanation?"

Right away I knew what my favorite candidate would be: the prevailing explanation for why the universe is lumpy. The explanation combines two of the most interesting and consequential ideas of modern physics: Heisenberg's uncertainty principle from quantum theory, and the separate idea, stemming from Einstein's general relativity, that space and time are as malleable as a trampoline. Even better, the explanation for the lumps leads to predictions for specific features that should be observable in the universe today -- predictions that match the latest data so closely it's almost uncanny.

First the lumps. Why is matter and energy distributed so unevenly when we observe the universe on scales ranging from the human-sized to the supergalactic? Why, in other words, should there exist huge concentrations of stuff -- massive clusters of galaxies like the Virgo cluster, cosmic equivalents of New York City, teeming with energy and activity -- separated by vast expanses of emptiness, nearly devoid of any matter at all?

A partial explanation comes from gravity, the most aristocratic of nature's forces. Under gravity's inexorable tug, the rich really do get richer. A region of space that happened to have slightly more stuff than neighboring regions at early times would grow more rich in matter over time: any slight excess would attract more matter thanks to its greater-than-average gravitational pull. The matter that glommed onto the slightly-more-massive region, in turn, would leave the regions whence it came even more depleted. Over a cosmic history like ours, which stretches nearly 14 billion years, this slow, creeping accumulation can add up to the huge disparities we see today in the distribution of matter and energy across space.

But where did the initial unevenness come from? According to our best explanation to date, those miniscule, primordial bumps came from quantum theory.

Physicists describe matter and forces in terms of fields. All of space, for example, is pervaded by electromagnetic fields, responsible for making electric charges attract or repel. At the quantum-mechanical level, one can decompose these fields as collections of quanta, or tiny particles -- in the case of the electromagnetic field, the associated quanta are photons, individual particles of light. Even simpler types of fields can exist. For example, the Higgs particle, for which physicists are so avidly searching at the Large Hadron Collider, corresponds to a field with even simpler mathematical structure than the electromagnetic field.

The exact state of a quantum field at any instant of time shows characteristic wiggles: unavoidable fluctuations due to Heisenberg's uncertainty principle. At any given moment, at any given location, the energy distributed in matter will betray incredibly tiny, sub-microscopic fluctuations, whose expected behavior physicists can calculate. Though wispy and evanescent, these quantum fluctuations can also be measured in a laboratory. In fact, for certain systems the theoretical predictions and experimental measurements agree all the way out to 12 decimal places -- one part in a trillion -- likely the single most precise and well-tested aspect of modern science. (How physicists learned to master such tricky calculations is the subject of my first book, Drawing Theories Apart.)

Now for the second step. All those fields of matter, with their eensy-weensy quantum fluctuations, live in spacetime -- as far as we can tell, a spacetime governed by Einstein's general relativity. Among the most surprising lessons of relativity is that this seat of the action is also a player: Spacetime warps and distends in response to the presence of matter and energy. Plop a large, massive object like the Sun in some region of spacetime, and spacetime itself will deform.

Not only does spacetime deform in the large, like a trampoline bowing around a bowling ball tossed in its center, but spacetime can ripple, like tiny waves skittering across an otherwise smooth surface of a pond. Many types of gravitational waves are possible, including simple ("scalar") waves of spacetime distortion. Those gravitational wiggles are driven by the tiny quantum fluctuations of matter: Jiggle a field of matter here and you will generate tiny ripples in the fabric of spacetime.

But how could sub-microscopic quantum fluctuations, with characteristic height and wavelength smaller than the size of atoms, possibly account for galactic-sized agglomerations? The answer, again: gravity. More and more evidence suggests that at the earliest moments in our cosmic history, the universe underwent a period of explosive, exponential expansion known as "inflation." (For accessible introductions, see the opening section of this paper, or, even better, Max Tegmark's lovely essay.)

As space stretched by an enormous factor, perhaps 30 or more orders of magnitude (a 1 followed by 30 zeroes -- yeah, a lot), the wrinkles of spacetime got stretched, too. Quantum fluctuations of matter and their associated wiggles in spacetime, which had started out with wavelengths many times smaller than the size of an atomic nucleus, would get stretched to macroscopic, even galactic, size. The wiggles, in other words, would stretch long enough in space to account for galaxy-sized accumulations of matter.

Calculating the properties of these spacetime wiggles -- how the height or amplitude of the waves should vary with wavelength -- was once a cutting-edge endeavor. Nowadays advanced undergraduates can tackle the calculation, at least for relatively straightforward models. (This is an empirical statement, as I have learned from working with an outstanding group of physics undergraduates this year.)

The upshot: Inflation should have produced spacetime wiggles across a huge range of wavelengths, each with nearly the same height, yet not exactly the same height. The models predict a slight tilt: Longer-wavelength wiggles should have ever-so-slightly greater amplitude (or height) than shorter-wavelength wiggles. Cosmologists characterize such a tilt in terms of a "spectral index," n. A perfectly flat spectrum, in which wiggles of all wavelengths have the same height, corresponds to n = 1. Inflationary models typically predict n less than 1. Calculations for the simplest models yield 0.95 to 0.97.

What about the observations? Amazingly, cosmologists can study these primordial lumps to high precision, based on the pattern captured in the cosmic microwave background radiation, or CMB. The CMB is effectively a snapshot revealing how matter and energy were distributed throughout the universe at the moment of the photons' release, about 380,000 years after the big bang. Photons that hailed from regions of space that happened to have greater-than-average concentrations of matter had to expend more energy to escape the extra gravitational tug, and so appear to us today to have slightly less energy than photons that came from underdense regions. The difference is minute, about one part in a hundred thousand, yet measurable nonetheless. (My wife even bought me a CMB plushie, either for inspiration or to facilitate naps in the office.)

Using a variety of ground-based and satellite detectors, most prominently the Wilkinson Microwave Anisotropy Probe or WMAP satellite, cosmologists have measured the distribution of bumps and wiggles in the CMB. The latest observations indicate a measured tilt to the spectrum, with n = 0.968 +/- 0.012: nearly but not exactly flat, and an astounding match to the theoretical prediction.

Research continues. Some cosmologists still actively look for alternative explanations to inflation, though (to my knowledge) none has yet come close to accounting for the empirical data with this kind of precision. Meanwhile, other, subtle effects could be lurking in the CMB, which would indicate more complicated dynamics in the very early universe.

But let us pause and admire the audacity of this beautiful explanation, stemming from simple but important ideas. The universe is lumpy because matter must obey the uncertainty principle, and spacetime is jittery. Elegant wiggles, indeed.

 
FOLLOW SCIENCE
 
 
  • Comments
  • 118
  • Pending Comments
  • 0
  • View FAQ
Comments are closed for this entry
View All
Favorites
Recency  | 
Popularity
Page: 1 2  Next ›  Last »  (2 total)
01:14 AM on 05/31/2012
The really cool thing about it is that none of the "aficionados" of the single photon/electron double slit experiment here have ever laid their hands on a photon multiplier tube or a single electron multiplier plate.

:-)
03:01 AM on 05/30/2012
I find it rather amusing that the "skeptics" of modern physics completely fail to understand 16th, 17th, 18th and 19th century physics, as well. See the example about charge conservation below... not to mention the folks who still think that they can make "free energy". Thankfully, at least the transmutation of lead into gold has gone, somewhat, out of vogue, already.

:-)
HUFFPOST SUPER USER
markgendala
A = Bx
01:23 PM on 05/29/2012
WHY INDEED...

"Extremes of QUALITY are inversely proportional to the FREQUENCY of their occurrence"

Macro-examples -
1. The "more" MASS M within given VOLUME - the "less frequent" the occurrence of such
VOLUMES - eventually culminating in a single "MOST M" VOLUME.

2. The "less" MASS M within given VOLUME - again, the "less frequent" the occurrence of
such VOLUMES - eventually culminating in a single "LEAST M" VOLUME.

Meaning? Theoretically, the Universe must divide into a grid of cubes the VOLUMES of which
contain MASSES presisely filling the entire contour of Bell Curve - from the "most" extremety,
through the great mountain of "average" right down to the "least"

This regularity of Nature is universal and applies to all aspects of complexity - Life included.
Micro-examples -

3. The "more naturally healthy" a person - the "less frequent" is such a person's occurrence,
theoretically culminating in a single "MOST naturally healthy" person on Earth.

4. The "less naturally healthy" a person - the "less frequent" is such a person's occurrence,
again theoretically culminating in a single "LEAST naturally healthy" person on Earth.

And so it goes, etc...etc...

Mark Gendala
Melbourne, Australia
www.ssotu.com
ThinkCreeps
Seriously, it's time.
05:49 PM on 05/29/2012
Well thanks very much for all that.
HUFFPOST SUPER USER
markgendala
A = Bx
07:46 AM on 05/30/2012
Thanks ThinkCreeps,

Bell Curve says "The greater the intellect, the less frequent its occurrence"
For example; the greater the capacity to "play chess" the less frequents its
occurrence - ultimately culminating in 1 (not two) World Chess Champion.

Alas, opposite extremety of Bell Curve also says "The greater the stupidity -
the less frequent its occurrence"

Which side of the Bell Curve do you come from? I cannot imagine you'd be
happy merely passing food through you body in that greyish, middle-region
netherworld of the "average"...

Stay well,
Mark
07:04 PM on 05/29/2012
More gibberish, mate!
HUFFPOST SUPER USER
markgendala
A = Bx
03:02 AM on 05/30/2012
Well lookie who's here - small world...

Science tells us the average density of the Universe is some 6 protons per
cubic meter, whatever... Let's call it MICRO-density...

But additionally, the "lumps" in the Universe should occur at rate of density
consistent with Bell Curve... Let's call it MACRO-density.

Assume it is a cube 10 by 10 by 10 million light years... What if the MASS
within billion of those cubes was measured and billion results corresponded
perfectly with the contours of Bell Curve?
We know the MACRO-density of the Universe...

Come on, SwiftJonathan - what's the MACRO-density of the Universe, i.e.
the unknown VOLUME which distributes its MASS along the Bell Curve?

M.
HUFFPOST SUPER USER
SKSagar
Superconsciousness switched on the bigbang
03:53 AM on 05/28/2012
Great article …. But I have a few things to say:
Ref …``More and more evidence suggests that at the earliest moments in our cosmic history, the universe underwent a period of explosive, exponential expansion known as "inflation." As space stretched by an enormous factor, perhaps 30 or more orders of magnitude (a 1 followed by 30 zeroes -- yeah, a lot), the wrinkles of space-time got stretched, too.``

Without doubt the Cosmological inflation explains many things including the homogeneity of the Universe. The question that arises is `What caused the CI`, or the big bang for that matter?
Why do we have to set an initial condition that there was something as `Zero time`.
`Why do we feed in the assumption about the direction of time ? --- we do not deduce it. We put it in as an initial condition.` ( John Wheeler ).

Likewise why do we become complacent and consider the Cosmological inflation as an initial condition.
When there is an explosion such as in a Supernova, the Quantum particles including neutrinos escape from the scene at no more than the speed of light. What was so special about the cosmological inflation of the big bang, that permitted the Quantum particles to violate Einstein`s special relativity and travel more than 10^25 metres in no time at all.

And above all ….why this `Zero time` initial condition?
(To be continued)
HUFFPOST SUPER USER
SKSagar
Superconsciousness switched on the bigbang
05:23 AM on 05/28/2012
And above all ….why this `Zero time` initial condition

True that was the beginning of this universe…but why not go back a little further into a territory known as `The last stages of the previous universe`… And consider an easier to believe hypothesis that it was the Super consciousness of the previous universe that prepared the programme for the new universe …. A programme devised in such a way that its implimentation did nor require the violation of any of the laws of established Science/Truth at any stage…and further that these laws of Science/Truths, will get clearer and clearer one by one in stages as time goes by and as the degree of consciousness increases ….ultimately.. after trillions and trillions of years reaching the Super conscious stage.

( For further reading refer my responses in 36 parts to Lawrence M Krauss` blog `The consolation of philosophy`)
08:51 PM on 05/28/2012
Once you treat "inflation" as a phase transition, all of these conceptual problems go away trivially. In order to be able to do that, you will have to first understand the not so subtle difference between "explosion" and "expansion". The two phenomena have almost nothing in common.

The "zero time" initial condition only exists in your mind. Nobody who is seriously considers cosmology expects that there is an order parameter like time that can be extended to zero and probably even negative numbers. Therefor, the "causality" problem (of the chicken and egg kind) that seems to block your mind also does not exist.
HUFFPOST SUPER USER
SKSagar
Superconsciousness switched on the bigbang
08:24 AM on 05/29/2012
Calling it as phase transition does not get rid of the requirement of finding a cause for the Cosmological Inflation.
Neither explosion nor expansion allows quantum particles to move faster than light and thus violate Einstein`s special relativity. Expansion of the universe is still going on and I am sure you know that it is not faster than sol.
But its Inflation we are talking about and trying to find a cause for it and an explanation for how the universe reached a size of 10^25 metres (radius) or more in no time at all…a tough job indeed for the Scientists … but there is ample time for it. This universe though 14 billion years is still an infant, it is substantially open and has trillions and trillions of years to live and if that period is considered as one year, then as yet it is less than a second old, and as I said before, there is ample time for getting at the truth…. Scientists will get at the truth one day …. But not those Scientists who believe in magic or those who believe `No cause is necessary`…nor those who are only concerned with `What happens`, and not concerned with `How it happens`…nor those who correlate it with the chicken and egg problem, and thus get complacent and say `why should we bother who came first`, not realizing that this `chicken and egg`problem is not something that is forever going to remain unresolved.
07:18 PM on 05/27/2012
In reading Gary zukovs' great book THE DANCING WU LI MASTERS,I became enthralled with the mechanics,and philosophical observations enclosed in the world of the quantum.Those that follow this path are my heroes of modern thought..
01:57 AM on 05/28/2012
So, in other words, you didn't dare to test your mind on the real thing (like a physics textbook on quantum mechanics) and decided to read total nonsense, instead.

:-)
07:42 PM on 05/28/2012
I would suggest you read Zukovs' work before you pass judgement..It was written at a formulative time of Quantum theory,and has a lot of humor,and parallels the eastern mystical worldview, popular at the time...I've read BRIEF HISTORY OF TIME,by Stephen Hawkins four times over the years,and have a copy of his UNIVERSE IN A NUTSHELL,that I pick up from time to time.. Quantum theory is a complex,and sometimes maddening field to understand(remember I'm simple minded)especially when you try to untangle string theory,and the whole multiuniverse thing.
I really enjoy Einsteins' thought experiments,and would love to be a part of the gang at Cern....But instead I'm just a lowley truck driver who likes to read,and am always open for suggestians for new horizions...Heading for Australia in the fall..
03:18 PM on 05/26/2012
My explanation--"lumpy" universe:

Hollow donuts and beach balls. H1. "Dark Matter". Duality. C^2. "God Construction" (not "particle".)

Imagine the crust of a donut whose ring and hole both have diameter 1 around and through which rolls a beach ball also of diameter 1. You could even call the donut hole a round zero with diameter 1.

For this most elementary entity no properties of anything we consider to "real" or exist. No mass. No distance. No charge. No energy.

For it rules of physics do not apply. One thing exists for it. Velocity--but this property is not based upon what we consider to be the constant--the speed of light. It is the velocity of light taken to its' own power, C^2 also be defined *for this construction* as C^0 or 1. One is the ONLY thing that exists for this construction! Why not zero? Because zero is a convenience of math that does not exist in the universe!

This is the most abundant construction in the universe *as a whole* as long as it expands. It becomes less abundant as it enters the contraction phase.

The most amazing property of this construction and the very reason that we will NEVER find it is that while the ball is going around the donut a true "thing" can pass through the hole with neither having ANY awareness of the other. These construction line up such that the smallest "things" appear to move through them in a wavelike manner.
07:48 PM on 05/28/2012
Nature doesn't use pi,or incommensurable numbers,but compensates,like an engineer,and doesn't get lost in the theory,like a physicist.
10:24 PM on 05/29/2012
No, nature doesn't use pi. She uses differential geometry, where angles in a triangle do not add up to 180 degrees aka pi. However, people who don't like to use pi will not find nature's way of doing things any easier.

:-)
photo
itruth
fideistic deist with socratic tedencies
09:07 PM on 05/24/2012
i get the feeling that we are selling books on this tour;and i do love books;however you slice the lumps;i still have a desire to understand [something from nothing] expanding at FTL speeds in all directions~time and spacetime radiate or dissipate energy through Entropy.

The other conundrum that i face is the entanglement must be acting in a superluminal spacetime by some quanta that can exit our demension enter another and find it's way back into our demension but at the other particles local;exchange identicle imformation with no time to do this?No wonder it gave Einstein the creeps...
photo
HUFFPOST SUPER USER
Stephen the Grate
There is grandeur in this view of life ...
01:29 AM on 05/24/2012
Current theories regarding the creation and expansion of the universe are indeed elegant and beautiful, as is our understanding of the synthesis of the elements and the formation of black holes and quasars. All lead to a greater understanding of our place in the cosmos and tell a story that, if you are not totally amazed and completely in awe of, you are not well informed.
08:35 PM on 05/24/2012
Well said.

Love your micro-bio. I read that passage, at my father's request, at his memorial service. It is among the greatest prose passages in the English language, I believe.
09:10 PM on 05/23/2012
... just one more thing.

The clincher that should prove to any sane person that Quantum Mechanics is total garbage is the following:

If we have a water wave, we know that the medium of the wave is the water.
If we have a particle wave, what does quantum mechanics say the medium is? They say the medium is "probability." Obviously, this proves that so-called physicists that are supposed to be studying "physical" matter have jumped off the deep end and are just playing with math with no understanding of the physical reality they are trying to describe.

P.S. This whole thought that a particle can act like a wave should have alerted physicists that their theory was wrong. Of course, it didn't though. Here is what is really going on:
When you shoot particles through diffraction gratings, when they come out some of the particles "beams" end up crossing the path of the other "beams" coming out of the other diffraction grating. When the angle is close enough, the magnetic fields of the particles cause the particles to pinch together much like two wires carrying current in the same direction will get pulled together. This results in one beam rather than two and so you see the patterns of light and dark.

Frankly, I don't know what it will take physicists to take a fresh look at their theories.
11:35 AM on 05/24/2012
Just one more thing... your kind is a dime a dozen. There is one of you outside of every lecture hall, craving for intellectual attention that you don't deserve.

:-)
09:43 PM on 05/24/2012
You know ... if only that were true. Instead, what I see are a bunch of yes-men that agree with every fantastic tale physicists spin.

When I went to physics lectures at the University of Winnipeg and the University of Manitoba as a physics student, what I noticed was that no-one and not even the other professors really understood what the visiting physics professor was talking about. So, it boggles my mind how they could agree with something they could not understand. And why was it not comprehensible? Basically, because physicists have made math their god rather than physical models.

P.S. Do you think Einstein was more like me or more like you? I mean, did he agree with the theories in vogue at the time? Not that I think Einstein was correct though. Also, for the record, I am not craving intellectual attention. I just want science to get off these dead-end paths they are on and move onto theories that really describe physical reality. I mean the fact that quantum mechanics believes that the medium for a particle is probability shows just how far we have gone off the deep end. If you can't see this, I don't know what to tell you.
HUFFPOST SUPER USER
markgendala
A = Bx
02:01 PM on 05/29/2012
SOME RESPECT, EH...

WHO IS PUTTING FOOD ON YOUR TABLE... More likely then not - it is
the very people who "crave the intellectual attention they (allegedly) don't
deserve" Hell, without them chumps like you would be warming pizzas to
earn a living...

So stop bluffing, old chump - scientitic bluffers like you a dime a dozen...
M.G.
09:58 PM on 05/24/2012
You know you get interference patterns when only one particle at a time is present, don't you?

Read the first few chapters of the third volume of the Feynman lectures. He points out how incredibly weird it all is.

Also, you seem to be concerned about having a "medium". What's the medium in which a photon propagates?
10:27 PM on 05/24/2012
I didn't mention it, but light is a particle and not a wave. When light travels through diffraction gratings, the same effect happens to light in that the beams get pulled together. Also, light or shall I say "photons" get created when ether particles get compressed together to form photons. This is how the ether ties into this.

As for shooting one particle, this is not true. First of all, we don't have the ability to shoot one particle at a time and secondly, the very idea is illogical from even the wave theory as you need the second wave to interact with the first wave.

As for Feynman, he is the classical case of how hippies have wrecked Physics. He made all these theories "cool" when in reality they should have been thrown in the trash can. I mean really. After light was supposedly discovered to be a wave after the diffraction experiments and then scientists shot whole molecules through and got the same effect, they really should have gone back to the drawing board and thrown away their theory of the wave. What are they going to do next, shoot a bowling ball through and expect the "wave" interference?
10:36 PM on 05/24/2012
One more thing...

Are you also not concerned that the medium they have "settled" on for a particle wave is "probability?" Also, the reason I am concerned is that by definition, waves require mediums, but I see that once again so-called physicists seem bent on breaking all laws of physical matter and have landed on the medium being "probability."

I submit that you should be concerned as well.
09:01 PM on 05/23/2012
... one more thing...

As for the electrostatic field, ether particles are randomly bombarding particles such as electrons all the time. However, put a second electron nearby and some of the ether particles end up between them and bounce back and forth rapidly -- like an old pinball machine. This puts more pressure between the electrons than the random bombardments outside of them -- hence electrostatic repulsion. The kicker is that as the magnetic field goes up, the electrostatic field goes down because the magnetic field acts as a shield of sorts to prevent random bombardments.
09:01 PM on 05/23/2012
Based on what you have written, the hippies have not saved science -- they have wrecked it.

Quantum mechanics is such a bad theory that even scientists don't understand it. It is based on playing around with fancy math and Planck's constant to come up with an answer. It talks of spin with wreckless abandon without even understanding why particles spin.

As for Planck's constant, it says that energy exists in discrete bundles. Now, why would that be? Well, because there is an ether contrary to what science has claimed. In fact, for a theory like "quantum" not to recognize the ether is strange. Planck's constant merely represents the energy of an ether particle. Now, since all energy interactions involve ethers, you can see how playing around with Planck's constant can get you the right answer ... eventually.

As for why particles spin, well since there is an ether made up of particles, as particles move through these ethers if they have a corscrew shape on one end (and they do), they will spin in the ethers like a propeller. This is also why moving particles create a vortex of ether particles around them that we call ... the magnetic field. Do you see how easy this stuff is and how obtuse and crazy modern physics is?
photo
HUFFPOST SUPER USER
Stephen the Grate
There is grandeur in this view of life ...
01:44 AM on 05/24/2012
You have rather strange ideas about QM. Quantum mechanics is spectacularly successful with respect to power and precision, and is way above any theory we have ever had to describe the workings and movements of the quantum world. Mathematically, the theory is well understood and physicists are in agreement. The question of what kind of a world it describes, however, is controversial. There is very little agreement, among physicists and among philosophers, about what the world is like according to quantum mechanics. I lean towards string theory in this regard, a beautiful theory in it's own right.
09:49 PM on 05/24/2012
I think based on what you have said that you agree with me. You have more or less said that by playing with Planck's constant and fancy math that they get the "right" answers, but that physicists don't actually know or agree as to what is happening physically. And that is the crux of the problem. Scientists need to understand things qualitatively before they can understand them quantitatively. And to me, this is not beautiful, this is backwards and crazy.

Lastly, as for strange ideas of QM, I was told that QM actually thinks it possible that if you shoot a bowling ball at a wall that there is a chance that it will act like a wave and pass right through! To me and to the rest of the world outside of scientists, this is the strange theory.
11:55 PM on 05/24/2012
That, of course, is complete nonsense. Physicists are in complete agreement that quantum mechanics describes the very world we live in and "philosophers", lacking any understanding of the topic, are of no concern with regards to this question.

String theory, of course, is not even a theory. As to it being beautiful in the sense of a physical theory (rather than a collection of mathematical objects)... that's questionable. For one thing, we don't even know what the correct dynamics of "the one" string theory is that supposedly describes the universe. Much more fundamental, though, is that string theory starts with a pre-geometry... which a truly fundamental theory can not. Thus, string theory is, at best, a collection of ad-hoc string models at this time (and has not grown fundamentally beyond this point in 40 years).

From a "philosophical" point of view, it is not clear why one dimensional topological objects should be any more "fundamental" than point particles. It is not clear why they couldn't dissolve into, e.g. "yarn" like quantum objects, which have an even more complex dynamics at even higher energy etc. ad infinitum (with topological objects of ever higher order forming a hierarchy of effective quantum field theories).
photo
HUFFPOST SUPER USER
musicmasterno1
Euthanize the dogfighter, not the dog.....
08:48 PM on 05/23/2012
My mother always worked wonders with mashed potatoes. I think she could easily remedy this lumpy universe issue you're having.
photo
phal4875
The world is run by cats; we just feed them.
03:56 PM on 05/23/2012
I cannot claim to understand all of what was written, but it is fascinating to try.
11:27 AM on 05/23/2012
There is something not mentioned in this interesting article which has me stumped. The current laws of physics (gravity, nuclear, e-m, quantum, etc.), about which the article seems to revolve, apply to ordinary matter, i.e., matter that we can see and measure. But, "Dark matter is estimated to constitute 84% of the matter in the universe." (wikipedia) So, since dark matter dominates ordinary matter, but is not subject to the known laws of physics except possibly gravity, how can anyone assert that the known laws of physics (quantum, for example) can be used to describe the observable distribution of mass in the universe?
08:42 PM on 05/24/2012
Dave can answer better than I can, perhaps.

Dark matter is apparently some kind of particle that just doesn't interact easily, which gets made in the Big Bang and then just sits there. It should very much be subject to the laws of physics, including quantum mechanics. Quantum is more of a 'meta-theory' than a theory of details of how objects behave (e.g., laws of electrostatics, color forces, what have you).

Dark energy is another thing entirely, despite the similar name. It's apparently a tiny residual energy density that exists in empty space. Quantum mechanics predicts that such a thing should exist -- but it predicts that it should be MUCH larger. Because of this, it had been assumed that some unknown mechanism caused it to cancel out exactly -- but apparently, the cancellation is not exact! No one knows just what to make of this, but again, it's not something that's outside the laws of quantum mechanics -- it's just something that no one expected.

Does that help?
photo
Chango137
Emptiness is form, form is emptiness
08:32 PM on 05/26/2012
"So, since dark matter dominates ordinary matter, but is not subject to the known laws of physics..." We do not know that the second part of that statement is true. You would have to describe dark matter, find it, so to speak, and then test it to see how it behaves. Since we don't know, the most reasonable thing to do is to go by what we do know. In the future, dark energy and dark matter may lead to new physics, if the past history of science tells us anything about the future. I think it is very exciting.
02:42 AM on 05/23/2012
nice topic