Cosmology is a fairly young science, one which attempts to reconstruct the history of our Universe from billions of years ago. Looking back so far in time is extremely difficult, and adding to the complexity is that many of the pillars upon which the theories of cosmology rest have only been conceived within the last 20 years or so. That hasn’t given scientists and theorists much time to fully flesh out and comprehend the situation, and cosmologist Michael Turner says either some important new physics will have to be discovered or we’re going to find a fatal flaw in our prevailing view of the Universe.
So, what will it take to push cosmology over the edge, where it goes fully from theory to science, and we have at least a grasp of cosmological understanding? I had the chance to ask that question to Turner at last week’s National Association of Science Writers conference. Turner, who coined the term “dark energy,” is the Director of the Kavli Institute for Cosmological Physics at the University of Chicago. Here are his top four wishes for discoveries in cosmology:
Wish # 1: Figure out the nature of dark matter.
“I think we’re very close to solving this dark matter problem and I think its going to be stunning when it sinks in to everyone that most of the stuff in the Universe is made of something other than what we are,” Turner said.
Dark matter holds universe together, according to cosmologists. But since it does not emit electromagnetic radiation and we can’t see it, how do we know it is there? “It is needed to hold galaxies together, it is needed to hold clusters together, it is that simple,” Turner said. “There is not enough gravity in all the stars put together to hold clusters together.”
Turner has likened dark matter to an outdoor tree decorated with Christmas lights. From far away, all that can be seen are the lights, but it is the unseen tree that holds the lights where they are and gives them their shape. More poetically Turner said, “The universe is a web of dark matter that is decorated by stars.”
Turner made a bold prediction: “The 2010 is the decade of dark matter – we are going to finish this thing off.”
Wish # 2. Figure out the nature of dark energy.
“Dark energy may be most profound problem in cosmology today, and I’ve been wandering around for 10 years saying this,” Turner said. “If dark matter holds the Universe together, dark energy controls its destiny.”
Dark energy likely makes up 66% of the cosmos, and it’s existence has only been theorized since 1998 when astronomers realized that contrary to the prevailing notion that the expansion of the universe should be slowing down, it is actually moving faster as time goes on.
What is the current theoretical understanding of dark energy? “We don’t have a clue,” said Turner. “But let me go out here on a limb with dark energy, and say we may find it is not vacuum energy. Vacuum energy is mathematical equivalent to Einstein’s cosmological constant, and I hope we’ll figure out it is something weirder than the energy of nothing. That doesn’t solve the problem, but it would be a gift to my younger colleagues, because science is all about big questions and they need clues and something big they can sink their teeth into.”
Yes, dark energy is a big problem, but for theorists it’s a big opportunity. However, Turner has some doubts. “Dark energy is one of the big questions that will occupy the next decade, and I don’t know if we’ll be able to solve it,” he said.
Wish # 3: Confirming inflation with the discovery of B-Mode polarization.
Our current best theory about the earliest moments of the universe is called inflation, where during a tiny fraction of a second after the Big Bang, the Universe appears to have expanded exponentially. In particular, high precision measurements of the so-called B-modes (evidence of gravity waves) of the polarization of the cosmic microwave background radiation would be evidence of the gravitational radiation produced by inflation, and they will also show whether the energy scale of inflation predicted by the simplest models is correct.
“That is the smoking gun for inflation.” said Turner. “It explains where all the structure came from – that quantum mechanical fluctuations at the subatomic scale were blown up by this enormous expansion. That is an amazing idea, and in one equation we could figure out exactly when inflation took place. You’ll notice in all our talk of inflation no one ever tells you when it took place, because we don’t know. But those B-modes would tell us.”
Wish #4. Make the mulitiverse go away.
If there was inflation, that means there is also very likely a multitude of Universes out there.
Turner called the concept of the multiverse the 800 lb gorilla in the room.
“The dilemma is, we have evidence that inflation took place and the equations of inflation say that if it took place once, it took place twice and it’s sort of like the mouse and the cookie – if it took place twice it could have taken place an infinite number of times,” he said.
The multiverse hypothesizes multiple universes or parallel universes comprise everthing that is, not just our one “local” universe. “If there is a mulitverse structure, and if you marry this with string theory you end up with a picture of a Universe where there might be different local laws of physics and the different sub-universes might be incredibly different from each other – differences in space and time, some don’t have stable particles, many don’t have life, and so on. This is an incredibly bold idea and may even be the most important idea since Copernicus.”
But, Turner asked, how do you test it? “And if you can’t test it, therefore you can’t call it science,” he said. “So I call it the mulitiverse headache – you have this incredibly important idea, but is it science?”
So what do you end up with? An elephant, Turner declared, as in the story of the blind men describing an elephant.
“That’s where we are in cosmology,” he said. “We are the blind cosmologists feeling the Universe and each piece of data describes something. There are still big questions to be answered, and what we’re doing in cosmology is trying to put it all together, and we might actually, in the next 10-15 years put it all together. That is absolutely amazing; the universe is very big and our abilities are very primitive. But look what we’ve done so far.”
Why the differentiation between theorists from scientists and theories from science in the introductory paragraphs? The second instance, viz “where it goes fully from theory to science” has a similar ring to is as “evolution is just a theory.”
That’s just what I was thinking Navneeth. Cosmology is already a solid scientific theory. Despite numerous attempts to remove Dark Matter and Dark Energy from the picture, the observational evidence (like the Bullet Cluster there) has solidified it too well.
While there certainly isn’t yet a unified picture (er… elephant) of all of cosmology, that’s not to say that we have reason to believe any of our current understandings are any way wrong. Just incomplete.
But incomplete doesn’t mean they’re not good or useful. After all, Newton’s idea of gravity was woefully incomplete and lacked the mechanism of curvature of space time. Yet we can still use it to send probes to other planets!
… No love for the dark flow?
My personal wish list is
1) Dark Matter/Energy basic presumptions go the same way as epicycles.
2) No Higgs, no gravity waves – start again
3) Redshift caused by something else, no inflation
My main departure would be with “making the multiverse go away.” It is not so much about defending the multi-verse, but with the nature of the concept. The Higgs vacuum expectation values we have are such that it appears highly unique. If there is a statistics for this occurrence it would be as if a pencil was thrown onto a table and it ended by standing on its point. This seems to be best thought of as being our view of a huge entanglement of states, where all orientations of the “pencil” actually exist. This in a nutshell is what leads to the multi-verse concept. So the reasoning for this is somewhat inescapable. This of course leads to the question of what we mean by these other “universes.” BTW, I hate the term multiverse. There might be a huge ensemble of spacetime cosmologies in the UNIVERSE — the unity of all etc, and where these exist in quantum entanglements or statistical ensembles with each other, but … there is only one universe. The nature of this points to some deep questions about the nature of quantum mechanics and spacetime. The one issue along those lines is whether these other cosmologies are sort of many worlds eigenbranches.
LC
Once again we hit that annoying gravity waves / gravitational waves confusion. I _know_ both terms are widely used to mean Einsteinian gravitational waves, the problem is there are _also_ classical Newtonian gravity waves, which are 2 completely different phenomena, both present in the early Universe. I have no way to know which of them is addressed in wish #3.
LC if you can, could you elaborate on what you mean by eigenbranches? Also, In your estimation, will there ever – no matter how remote – be any possibility of actually testing for the existence of these other space/time cosmologies?
Manu, I am not sure what you mean by Newtonian gravity waves. There are something called gravity waves in atmospheric physics. These are vortices set up by two different air layers moving across each other. The pressure in these vortices is lower and water droplet or ice crystals can form in them. When you see clouds in the sky with a regular tiger stripe appearance those are due to gravity waves. Those are indeed different from gravitational radiation. With Newtonian gravity F = -GMm/r^2 there are not gravity waves.
Will we ever test for other cosmologies? That is tough to say. There are two levels of cosmologies. One of these is the pocket universe. The whole spacetime is an infinite R^3 space which is undergoing rapid inflationary expansion. The vacuum there is over 10^{100} the density of the vacuum we measure, and this sets up a huge cosmological constant that expands the space enormously. There are then defects in the inflaton vacuum which can be set up that drastically lowers that vacuum energy and the energy difference goes into the production of particles. We are in one of these bubbles of nucleation, which Sydney Coleman developed back in the mid 1980s. So there are likely a whole gaggle of these. These pocket universes are generically identical to ours, but the Higgs vev is likely different and so the general features in them may be radically different from ours. The other forms of cosmologies are entirely different spacetimes, which may have entirely different structures far different from pocket universes. Each of these may have their own pocket universes. These exist according to Dp-brane interactions and are quantum correlated or entangled with each other.
Can we measure any of these? At best we may do so only very indirectly. We might be able to detect pocket universes by finding that we indeed are in a pocket. Small deviations in homogeneity or isotropy may illustrate this. The Dp-brane cosmologies might be detected indirectly through some delicate measurements of the vacuum state or with gluon chains which are equivalent to soft gravitons. Of course we have to find these in the LHC first. In effect there should be an inbalance in the sqrt{s} in scattering which might account for the generation of a nascent cosmology.
There are actually two other levels, and one of them is the many world interpretation. Eigenbranching corresponds to the appearance of a wave function collapse, and where the world branches into a multifold process along each of the probable eigenstates which could be measured. This is a third level, and I think with quantum gravity it might be equivalent to the Dp-brane approach. The fourth level is the Tegmark Platonia, where in effect all possible mathematical structures can exist in radically different cosmologies However, this is probably far too “out there,” almost metaphysical for me to speculate on and I doubt we will ever measure anything connected to this.
The important thing in quantum physics is the Hilbert space of states, not configuration space — such as spacetime. A wave function in ordinary sense has identical copies of configuration space. With quantum gravity this is not the case, which leads to some curious difficulties. A wave function which extends into a black hole has states with different configuration space variables which are not causally connected. This may also extend to the problem of different cosmologies on the Dp-brane level as well.
LC
My other three questions would be much different;
1. Why is the universe so axiomatic?
2. Why is the fine-structure constant (α) set at 1/137? [Actually 137.035099679(94) ] IMO The anthropic principle idea just doesn’t cut it, and does it apply across the universe and at all times.
3. Will the universe ever end?
Not mentioned for the cosmologists dream, is that the big-bang redshift-distance determination uses inflation and Hubble’s law as the cosmological constant, and entirely neglects local absorption effects predicted and discovered at 850 microns. Lerner says the CMB is not istropic, but a radio fog of dense magnetically confined plasma filaments. The CMB background anisotropy is strongly oriented quadrupole and octopole power on a ring essentially zero along the axis direction toward the Virgo cluster and lies EXACTLY along the axis of the local supercluster filament of which our galaxy is a part. the matter energy density and its absorption effect increases along this axis direction, and the local intrinsic redshift components produce higher redshifts when looking through more plasma thickness and length, then when viewing away at different angles. Quasars are examples of high redshifts explained by gravitational lensing, which Arp says his catologue photos show luminuos connecting filaments. Plasma cosmologists and big-bang theorists need to work together and unify cosmology! Inflation and the big-bang is entirely dependent on current redshfit-distance interpretations which Arp says keep astronomy and science in the dark ages!
Heaving dealt with the ideas of cosmologists for some decades, i feel that it is less about the factual history and properties of the universe but more about the human (in)ability to understand it.
The quality of this understanding depends on that what the person knows, on that what that person could know but unfortunately does´nt, and on the lots of facts that nobody knows yet and still have to be detected.
Developing a science on such a basis is a brave and fascinating endeavour.
The anthropic principle has two forms, the weak and strong AP. The two are logically different.
The weak anthropic principle tells us that the world must be of a certain form in order for intelligent life to exist. This in effect motivated solar physics in the early 20th century. The classical model was that the sun was illuminated by gravitational compression. As the sun continued to collapse then by pV = NkT this increased temperature. However, this could only work for a few tens of thousands of years. Geology and biological evolution told us the world was many tens of millions of years old. So the physics had to adjust to the geology and biology, and this lead to nuclear fusion. With respect to so called fine tuning and the rest we have a similar situation.
The strong AP says that in order for the universe to exist there must be conscious intelligence. This is sufficient condition on the weak AP. The weak AP is the necessary condition: if there exist intelligent life the world must configured accordingly. The strong AP says: for the universe to exist there must be intelligent life. The main objection I have to this idea is that it is not testable. It appears to be more of a metaphysical concept that I doubt could ever be tested, even if it should be true.
The value of alpha = e^2/hbar-c is one question in line with the whole fine tuning problem. Ultimately it is a question on the vacuum expectation (vev) of the Higgs field. It is my thinking the value of these gauge parameters or the Higgs vev is “all of the above,” but where we perceive values commensurate with our existence and the world we perceive. We observe the values we do as entangled with all other possible field configurations, but where there is an entanglement entropy that betrays our lack of information on these configurations. This entropy in an information theoretic setting, or quantum information setting, is a measure of our lack of knowledge.
As for the Higgs field, it is a theory similar to the Landau-Ginsburg theory used in superconductivity, superfluidity, ferromagnetic phase change and … a whole range of stuff. Quantum field theory also clearly goes “sick” at around 1 TeV as it is, so it is clear there is some sort of change or phase change which takes place. Higgs theory is the most reasonable candidate(s). The plural refers to the minimally supersymmetric standard model (MSSM) where there are multiple Higgs vacua and a charged Higgs sector.
LC
@LC: yes, these are what I was talking about:
http://en.wikipedia.org/wiki/Gravity_wave
I have a vague memory of reading there were waves of this type in the early universe, as well as sound waves, and that both generated fluctuations which expanded into visible large scale structures, just like the pre-inflation quantum fluctuations did.
Maybe I got this wrong though.
quite the reverse is true of every criticism LC wrote about me. the big-bang blow up universe beginning makes no logical sense and is all based on a misinterpretation of redshift. your 400 year old gravity universe is a buncha crap too, to make money and teach incorrect beliefs handed down over the ages, including adding in your stupid dark matter neutralino particles. Alfvan’s work is only 30 years old not 40-50 years, but i doubt you’ll perceive what 30 years makes. the plasma equations are too complex even for you to figure out. your 90% invisible universe beginning cannot be explained, because the universe is infinite in time and always existed as plasma which is common sense.
@ Manu: There are acoustical modes which were likely established in the post inflationary/reheating phase. Gravitons decoupled from the other quantum fields and were stretched into classical gravity waves. It is analogous to photons that in a classical limit define electromagnetic waves. These classical gravity waves then likely left imprints on the CMB, which are the B-modes. These B-modes are due to imprints on the spacetime from gravity waves, which coupled into matter to generate acoustical waves.
JIMHENSON This stuff your write makes no sense. I really wish that Arp and Alfven were dropped from everyone’s lexicon regarding cosmology. Their hypotheses were drawn up in the 1960s and falsified not long after. This is 40-50 year old stuff that is completely dead and should be buried for good. It astounds me to see people who take up wrong science and make some passionate career out of promoting it.
Thanks! =)
Hey Muppet,
Alfvan’s work is antiquated rubbish, as is much of the EU/PC claptrap. It fails nearly every test and prediction;.and lays unproven through any real evidence.
As I said before; “Dreams of something being true doesn’t make it so!”
Your idea of reality is plain and simple — claptrap!
(I you want someone to bury you too, along with Anaconda and the other feeble-minded dipstick, I’m your man! Back off brother!)
In a more retrospective sense I find it astounding that people can so ardently uphold this stuff. Creationism is at least understandable, for that is a part of a whole package involved with divine issues of eternity and the like. Yet EU/PC stuff holds no promise of eternal salvation, so there is no motive there, and secondly it is so hopelessly flawed and falsified by observation. To be an EU/PC panegyrist might compared to a student who takes an elementary chemistry course, but snags up their education by being a diehard upholder of phlogiston theory, and in the end fails the course.
LC
Lawrence,
What dawned on me is the reason EU/PC hold that; “…the universe is infinite in time and always existed.” It has to be this way because it cannot explain the origin of the plasma (let alone the rest of the other forces and the matter in the universe!) I’d assume that the only way they can to explain matter, gravity, strong and weak force, quantum mechanics, etc. is that is was somehow was created by some bizarre plasma field. This is what these nutters are so ardent the plasma (and magnetic fields) explains everything, but are happy to ignore everything else in the universe as inconsequential. Logically it is wrong, so why do they persist with it mind-numbing! Crazy.
thank you all, especially Universetoday, for letting me post my belief in plasma cosmology. there are no faults with PC, except that “it cannot explain the source of the energy.” says my famous scientist who is an expert fusion physicist. He states that the big-bang is illogical and sketchy at best, and the conclusions are irrational. Wiser people do not want to accept an explanation given to them handed down by scientists as an absolute fact, on how the universe began, without explaining the source and reason why and where did it come from? Plasma space as eternal, to me, seems far more rational. Why an infinite, dense, hot singularity blew up and suddenly expanded, but can’t even be explained why to have existed, to me is not acceptable and falls right into the realm of nonsense. Nobody here can deny that the LHC experiments are attempts to study the “big-bang” beginning of the universe. My expert IS in dense plasma fusion labs using magnetic field confinements, and not on his behind reading stuff that he already believes in. He doesn’t believe in the big-bang, and states that PC is the best cosmology that we have today! So go on and believe what ya want with enough time we will all learn the truth because we live in the days where better and better observational equipment is being developed.
I get the sense there is also what I might call an Ayn Rand agenda with this as well. She made oblique comments about modern physics that were not complementary. The PU idea puts the universe in a nice objective “bottle” of sorts and gives a sense of control. Several years ago there was the Oil-Master guy who posted here, who had some strange economic-technology agenda wrapped up in his PU nonsense as well. So this all seems to accompany some underlying philosophy similar to Ayn Rand’s sterile concept of Objectivism.
LC
LAWRENCE B. CROWELL,
Interesting. I always felt that the tone in which EU/PC people argued, there was a sense of moral injustice being fought against. They’ve always argued that to them the mainstream science is pushing idealogical concepts that or wrong. There is a moral undercurrent in their arguments and driven by how the world should be measured and judged rather than an understanding of the science itself. As you can see I have a morbid fascination about what motivates these guys.
Something like that is afoot. I think one of the problems is that science of late has given us some really bad news. Ideas about faster than speed of light travel are simply out of the question. Future plans with standard space travel and ideas of space colonization are fading fast. It is not at all clear any of that is going to work out. Nuclear fusion looks very questionable, and even nuclear fission is not doing well — it does not so far economically work. Then we have all the environmental stuff, but I will avoid getting mired into that. So things just look pretty bad when contrasted to the “Disneyland” ideas we had about the future back in the 1950-60 time frame. So the rise of this alt-science seems to be a cult-like mentality that is setting in about a techno-elixir that will fix all of this and get us back on track to putting Clavius city on the moon (2001 Space Odyssey) and so forth. Then with that has to also come conspiracy ideas about mainstream science in a deception role or that it is beholden to evil forces out to …, well you get the picture.
Along with this Ayn Rand has become immensely popular of late, where in her last novel Atlas Shrugged, her main hero invents what amounts to a perpetual motion or free-energy machine. It is also worth noting that her characters were in part modeled after her early fascination with a serial killer, who was to her the model of a person who pursued ambitions with no regards for society. Hmmm … people like that we normally call sociopaths.
LC
KUDOS to you Nancy for posting this timely article, considering the ongoing debates here in the comments sections as of late.
Your article even lists some reasons for doubt that I wrote about here just a few days ago. Some here don’t like it when I ask these questions so hopefully a recognized expert like Mike Turner will cause them to at least consider that there is no true general agreement as of the present time on the “dark” theories and inflation theory. With the exception of question #4 (multiverse) I support Mr. Turner’s questions as being the most pressing in modern comsmology.
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On a different subject:
The EU “fights” here are what marked the beginning of the degradation of this forum and every time you guys bring it up and rehash the same old arguments, people leave. A very good friend of mine who used to post here quite often left because of it and as far as I know, has never visited this site again. Why would you want that? If it’s such “claptrap”, why can’t you ignore it and relegate it to the dust bin of history where you so insecurely insist that it belongs?
@ Muppet
There is no belief (or faith) in science. It is based on evidence and deductive reasoning. Your are confusing science with religion.
So everything you say here is someone else’s opinion, not yours. Frankly “your friend” cannot explain the source of the plasma or the magnetic field for that matter! The biggest problem for you is plasma cosmology has been rejected as absolute crap — by astrophysicists and not by unqualified and unrelated electricians.
You “friend” is quite ill-informed and clearly doesn’t understand what he is talking about. Also that is HIS opinion, whose conclusion is not based on the evidence.
Wiser people would understand that explanation of science is based on observation as evidentiary evidence, whose conclusion explains the phenomena. I.e. The universe is expanding because evidence shows that the further the distance a galaxy is, the faster its velocity. Hence, the universe going backwards in time must have had a “beginning.” Is this not your “absolute fact.”? Cosmology concludes the formation of our universe happen in a singular event (called the Big Bang), whose evidence is based on cosmic background radiation, etc.
Information is never “handed down by scientists” (that is what the media does), it is based on observation, deduction, explanation, then forming a valid are reproducible conclusion.
Yeah. But that is also opinion, and from the gobbledygook in your own words,
is these same illogical “absolute fact” you accuse scientists of doing! Where is the real evidence for this statement !!!!!!!!!!
“Argue you limitations, and sure enough their yours”
Let’s see. Your assumption that an “infinite, dense, hot singularity” “blow up” does not describe the Bog Bang!! Cosmology does not say this at all!
Really. Just because YOU don’t understand it does not equate that “…not acceptable and falls right into the realm of nonsense.” All it shows is your mind-numbing ignorance!
So what! Is it not also true that is not the only “attempt to “study the “big-bang” beginning of the universe.” is it? I.e. Measuring variation is the cosmic background radiation or observationally study the earliest structures in the universe.
Gain this is quoting someone else. You “friend” is no astrophysicist or cosmologist is he, just a mere electrician (probably IEEE). If he were a scientist and just “believes” this is wrong, he isn’t a very good scientist. [I’m starting to think your friend is “imaginary.”]
He clearly is delusional if he believes that, and would be laughed out of astronomical or cosmological conference. Even so, he would be among 0.001% of any astrophysical scientist to hold such alternative view.
Oh dear. Science again isn’t based on “truth”. It is actually based on evidence and using the scientific method to deduce valid conclusions.
Plasma cosmology (PC) utterly fails every test and prediction; and lays unproven through any real evidence to support it. For this reason it has been rejected by astrophysics and cosmological science.
Those who believe it true are indoctrinated fools who are just dabbling in illegitimate “pseudoscience” — conned by people who really should no better! I pity you muppet!
As I said before; “Dreams of something being true doesn’t make it so!”
Cappa said;
The same old argument. You just don’t get that these EU/PC individuals have an agenda to spread their ill-informed views on unsuspecting readers of this site. They aim to trick and deceive people to their supposed commonplace views are really legitimate astronomical and cosmological science, when in fact it has been mostly completely rejected by mainstream science.
Sadly ignoring them doesn’t make them go away, so the only way is to discredit them at every opportunity.
I’d ask you instead. Do you want to read and digest legitimate news on science, or be tricked by individuals who want to sucker them into their already known agenda?
Gurzadyan and R. Penrose have written a curious paper
http://arxiv.org/ftp/arxiv/papers/1011/1011.3706.pdf
on concentric circles in WMAP. These are argued by the authors to be a case of pre-big bang physics. I think this might be an indicator of something with the independent degrees of freedom in quantum gravity and cosmology.
The argument for this is in some sense interesting, but I question whether it is for the reasons the authors claim. The conformal rescaling of the metric g_{ab} –> ?^2g_{ab} rescales the Weyl curvature ?_{ABCD} – -> ??_{ABCD} if there is a 4-dim spacetime. In dimensions lower than 4 there is no Weyl curvature, so to push the Weyl curvature across the CCC I they seem to be saying there is a continuous flow of geometry. Their argument assumes that the CCC infinity I the spatial surface is smooth or flat. So the gravitational degrees of freedom on the other side of the CCC I are not carried over to our side. So the wave equation nabla^A_{A’}?_{ABCD} = 0 across this region I is such that the rescaling conformal parameter appears to take up those degrees of freedom as other forms. This is interesting to think about with respect to the problem of degrees of freedom in quantum gravity. In particular with regards to how it is that loop variable quantum gravity imposes a huge number of independent degrees of freedom on quantum or noncommutative spacetime, when this in fact appears to be a huge over counting. However, what troubles me with respect to the argument about there being some propagation across the CCC I is this still presumes some continuous spatial geometry across the CCC I. However, if we were to assume that nabla^A_{A’}?_{ABCD} = 0 tells us how spatial geometry propagates the vanishing of gravitational degrees of freedom at the CCC I from our perspective would seem to imply there simply is no spacetime geometry at all which we could extend beyond I.
So these data might indeed be telling us something, but I wonder if it is what they claim with regards to “pre-big bang” events, or whether this might have something to do with the nature of gravitational degrees of freedom at the big bang.
LC
1) Dark matter is ordinary old mass-energy that is simply less dense than ordinary matter is, so it doesn’t interact except gravitationally.
2) Dark energy is ordinary old mass-energy that isn’t gravitationally condensed around massive objects. It has negative pressure because it has -rho, so it causes the universe to expand.
3) Inflationary theory is falsified by the lack of a need for it when a universe with certain volume has a big bang because…
4) There is no stinking multiverse.
Call me when they don’t find the higgs or higher dimensions:
http://www.longbets.org/476
As usual, the EU/PC cowards run away when faced with the facts, at least until the next story. . . See ya round, Muppet…
multiverses and parallel universes are nonsensical conclusions from the big-bang, that are explainable by EM forces and scalable dimensions of plasma physics. No satisfactory refutation of PC exists, the best they do is lie about it, because grants and governments fund big-bang cosmology institutions keeping it a dream scheme model of invisible matter and energy. real plasma researchers, like the IEEE, has over 50,000 brilliant professional plasma scientists helping society build and discover new things. The same laws of physics in the labs apply to stars and galaxies, and the jets, x-rays, gamma rays, are all produced in the lab without black holes and dark matter. Alfven won the nobel prize in physics in 1960, and the readers depart from here, because they want to find out more about plasma cosmology after hearing the same old crap from guys like crumb. The baby big-bang universe always gets bigger and older when they see farther out into space, discovering older galaxies existing, that are older then predicted by the big-bang. This is course is not going to disappear but intensify, and will lead to the demise of the big-bang, when our visible horizon expands to see galaxies 20, 30, 40 billion years light years away! Then the ego-centric heads up the big-bang will realize that the universe is older then 14 billion years, and is older then as far as they can see! If light has to travel 100 billion years to reach our visible horizon from distant galaxies, then the universe is still at least 100 billion years old. You can’t fool me with words or math to convince me that the universe is still only as old as the big-bang that you invented, and not as old as space, distance,and light itself. the big-bang is like believing the earth is the universe, and they are at the center of it, and everything is expanding away and increasing because of silly dark energy. Dark matter and dark energy can’t be explained away, because you can’t even discover it nor prove it. Go play with magnetized steel wool and make spiral galaxies on a flat screen !
Personal accounts are always interesting, if idiosyncratic.
Not really, since already WMAP test inflation at 2.6 sigma IIRC. And hopefully Planck will deliver the exacting “smoking gun” test we wish.
But I can see why these modes are exciting now.
You test it the same way you test other theories, on their predictions.
Famously, atomic theory was tested (accepted) with the discovery of Brownian motions and Einstein’s model of it. We accept atoms and fundamental particles even if we can’t observe them directly. The same goes for fields.
And the same should go for multiverses. (That is not even considering the hypotheses of testable bubble universe collisions for some parameter ranges in some models, that would make explicit observable imprint as well.)
Environmental theories of multiverses makes at least 6 testable predictions. In fact, that is more than the 5 main testable parameters of standard cosmology, so multiverse theory is more predictive than universe theory.
Only a throwback to “old times” would hesitate to call this science, IMO. Each generation will have to overcome the conservatism of the old, compare with quantum theory.
What remains is actually “only” to test inflation theory on the set of multiverse solutions. I.e. unless inflation is chaotic or some other model that permits multiverses, multiverse theories fails despite already passing the other tests that has been put before them.
Then we must find the explanation for the unlikely choice of parameters elsewhere, how unlikely that seems today. (See LC comment on pencil throwing.)
@ LC:
That is, as always, a definitional issue as you yourself allude to. The universe has expanded from a planet to “an island universe” (galaxy) to “the visible universe” to the seemingly infinite FRW universe. It is not necessary but practical to keep it there, otherwise the FRW model would call for another term.
If the multiverse theory is correct, there is an potentially infinite nested set of such “pocket” universes that paints the locally end of inflation. Moreover there are potentially an infinite set of such sets, since by its nature inflation can start anywhere from quantum fluctuations.
It is not meaningful to think of these as a coherent set; by which measure would one define “unity”? (This, defining multiverse measures, is in fact a long outstanding problem! It is by now doubtful that it has a solution.)
So FWIW I find the term multiverse a good descriptor of the multitude of different and in the end incoherent set of universes.
@ HSBC:
What do you mean specifically? Generally physics is algorithmic, not axiomatic, since there are theories like 2nd quantization that resist axiomatization.
That is exactly what we would expect on the grounds that:
1) Math, or more generally computer science, is algorithmic. Axiomatic theory is a useful but minute subset.
2) Physics has to work with local natural resources as per quantum mechanics, no hidden variables. If what we see map to the substrate, which we would expect from naturality, parsimony and reality (tested by observing specific reactions to actions), there should be a mapping between our algorithmic theories and physics, suggesting physics is algorithmic.
Torbjorn
I meant; axiomatic – meaning self-evident or unquestionable
The question is more philosophical like “why is it as it is, and not something else.”
Hey Muppet,
Your a dead-set nutter and can;t get his facts straight!
Alfven won his nobel prise in 1970 (not 1960), which he won for “”for fundamental work and discoveries in magneto-hydrodynamics with fruitful applications in different parts of plasma physics” Plasma cosmology wasn’t one of them!
What don’t you understand?
PLASMA COSMOLOGY and the ELECTRIC UNIVERSE IS UTTER CRAP, and HAS BEEN REJECTED ENTIRELY BY ASTROPHYSICS and COSMOLOGY !
Crazy rants like this make me just sad. Please, stop making yourself look like a total idiot!
Salacious Crumb you are a scum bag cocksucker who kisses butt everytime. Your words are crap and you’re always full of insults. I believe the experts of Plasma Cosmology, and not some disrespectful brown noser like you who can’t honor your word. Crumb always makes up lies because the big-bang is dead but you butt kissers always keep it going here. I’ve stated enough facts, and you guys still can’t offer a single refute to PC. Like always Crumb, all you can do is suck up to Crowell and his buddies, and bad mouth plasma cosmology by comparing it to the EU stuff. Go screw yourself Crumb and pull your head out of the butts
@ Desperate Muppet
Charming. All you can do is resort to is profanity to make your worthless case. Ranting and raving about nonsense you have no inkling of digs you in a deep hole.
Please, stop making yourself look like a total idiot!
I really pity you, you poor sap. Go get some help.