What If Dark Matter Really Doesn't Exist? 1063
sonar67 writes "According to The Economist: 'It was beautiful, complex and wrong. In 150AD, Ptolemy of Alexandria published his theory of epicycles--the idea that the moon, the sun and the planets moved in circles which were moving in circles which were moving in circles around the Earth. This theory explained the motion of celestial objects to an astonishing degree of precision. It was, however, what computer programmers call a kludge: a dirty, inelegant solution. Some 1,500 years later, Johannes Kepler, a German astronomer, replaced the whole complex edifice with three simple laws. Some people think modern astronomy is based on a kludge similar to Ptolemy's. At the moment, the received wisdom is that the obvious stuff in the universe--stars, planets, gas clouds and so on--is actually only 4% of its total content. About another quarter is so-called cold, dark matter, which is made of different particles from the familiar sort of matter, and can interact with the latter only via gravity. The remaining 70% is even stranger. It is known as dark energy, and acts to push the universe apart. However, the existence of cold, dark matter and dark energy has to be inferred from their effects on the visible, familiar stuff. If something else is actually causing those effects, the whole theoretical edifice would come crashing down.'"
Re:No dark matter ? (Score:5, Informative)
Re:Resistance to change (Score:4, Informative)
If the data is there and convincing, the views will change. But any alternative theory is going to have to explain all the observables, not just the two mentioned in the artice.
(E.g., the convincing data on dark energy comes from two independent groups studying supernovae.)
Re:Brief History... (Score:5, Informative)
You keep telling yourself that... God boy. However only 7% of scientists believe in a personal god [atheists.org].
Sorry to be nitpickin' (Score:3, Informative)
Re:Resistance to change (Score:1, Informative)
actually... (Score:3, Informative)
Actually, most Physicists don't believe in God.
Re:Something odd with gravity (Score:5, Informative)
This question we may actually know the answer to in a decade or so when the LHC comes online and is producing results.
Dark energy is much weirder.
Re:I hope its a kludge (Score:1, Informative)
Well, optimism doesn't drive research, unfortunately. It's really not about preference, but science. The two are unrelated really. I don't like the fact that I can't eat buckets of spicy cheese and drink high life bottles without getting like an obsese shit, but it's fact.
I think you'll have to come to terms with reality.
No. (Score:5, Informative)
No, Relativity (neither the Special nor General theory) says that "everything is relative". Special Relativity says that inertial motion is relative in flat spacetime (i.e. in the absence of gravity). This is another way of saying that all inertial coordinate reference frames are equivalent. (Special Relativity says more than that, namely that light propagates at the constant speed 'c' independent of the motion of its source. This is what separates Special Relativity from Galilean Relativity.) General Relativity says that *locally*, accelerated motion is equivalent to inertial motion in a gravitational field. (The "locally" part accounts for the fact that the gravitational field lines are not parallel, but converge on the gravitational source.)
What this boils down to is that circular motion is accelerated motion, not inertial motion, and is not simply relative, and spacetime is not flat surrounding bodies that planets orbit. So no, Relativity does not validate the epicycles theory.
Re:Sorry to be nitpickin' (Score:1, Informative)
From a science standpoint, an interesting theory makes predictions which can be disproven. Some scientists then try to observe the prediction to support or disprove the theory. Other scientists accept the theory is right and use the predictions while on their way to doing other stuff.
Re:Correct me if I'm wrong... (Score:3, Informative)
Re:Relativity (Score:4, Informative)
The key word here is inertial. An orbiting body is accelerating towards the center, and is therefore not an inertial frame of reference by definition. As far as calculations on the surface of the Earth go, non-inertial effects (also present because of Earth's rotation) can generally be ignored for comparatively small times and distances without significant loss of accuracy, but on the scale of the Solar System and other systems where celestial mechanics are employed, they cannot be ignored. Epicycles introduce a new non-inertial component, and therefore can't be regarded as merely relative.
Re:Relativity (Score:3, Informative)
No, because rotational motion isn't linear motion. A given linear motion will look like any other linear motion from the correct point of view. There is no (sub-light) vantage point from which the Earth does not have a path that describes an orbit around the sun. (That orbit, the Earth, and the Sun can appear squished and time dilated, but the path the Earth follows will always be around the Sun.)
You can define a Point Of View where your position on the surface of the Earth is the constant zero point, but it's going to be very exicting defining the rest of physics usably. Anything further then a light-(day / (pi*2)) away is traveling faster then the speed of light, for instance (appears to travel more then one light-day per day). Again, this is because rotation isn't linear motion.
I think you could theoretically kludge physics to work that way, but what you have is a God-awful physics where the speed of light varies based on which direction you're traveling and how from the zero point you are, and in the end, it makes the exact same predictions as what we have now. There are an infinite variety of theories that make equivalent predictions to any given theory, and are thus in some sense equivalent, but as humans, we prefer the simplest for a lot of reasons. You could build a consistent Ptolemaic theory, but you wouldn't want to.
Re:Theory. (Score:3, Informative)
But if you want examples of speciation:
http://www.talkorigins.org/faqs/faq-speciation.ht
http://www.talkorigins.org/faqs/speciation.html [talkorigins.org]
That's not correct. (Score:3, Informative)
Orbital motion results from acceleration caused by gravity. One can measure acceleration locally at any point within the influence of the gravitational field. Thus, symmetry between difference frames of reference are broken, and a natural "center" is defined as one of the points where one experiences no acceleration. In reality, you never have a true "center" in a multibodied system such as our solar system. However, the Sun is so massive that we can say, to reasonable accuracy, that the center of our solar system is approximately at the position of the sun.
Re:Sorry to be nitpickin' (Score:3, Informative)
Typically a hypothesis is when you think 'may be the universe is like this', and you try and find a way to prove or disprove that argument.
A theory is what you get when you observe reality and try and find a rule that governs that reality.
Both processes involve creativity, supposition, observation and either confirmation or refutation.
As such, both theories and hypothesis can be proven wrong.
I don't think it's a good idea to start judging scientific ideas on any other basis than comparison to reality. Limiting yourself to semantics is silly.
Sorry to be nitpickin.
Re:I Wish I Was a Scientist (Score:5, Informative)
When scientists look at the way that galaxies move through space, they see that many of them move a great deal faster (about a factor of 10) than theory predicts. Assuming that current theory is correct, the most likely explanation of these observations is that there is a great deal more matter in the universe than we can currently detect. If we can't detect it then it must be pretty much invisible across the EM spectrum, so scientists have christened it dark matter. Much effort has gone into trying to prove its existance but as as far as i'm aware there has not been too much sucess.
As I remember from my astrophysics class (and this was some years ago so feel free to correct me) there are two main candidates for dark matter, both of which have been tediously acronymed.
MAssive Comapact Halo Objects (or MACHOs) are basically chunks of ordinary matter, floating around in space that give off no radiation. Think brown dwarfs (stars without the necessary mass to initiate fusion). As I remember, most scientists are very sceptical that a significant amount of dark matter could be contained in MACHos.
Weakly Interacting Massive Particles (WIMPs- gotta love that scientist humour) are the other candidates and are hypothetical particles, heavier than neutrons, that were formed in the Big Bang and have been travelling through space ever since. As their name inplies they would have almost no interactions with normal matter and so by definition would be almost impossible to detect. Again there have been attempts to prove the existance of these particles, mainly involving mine shafts and a lot of water, and again there have been no conclusive results.
Now the significance of all this is that as you may or may not know, the universe is presently expanding and will continue to expand for some time. What will happen after that, however, is a matter of some confusion. One theory says that it will continue expanding forever (open universe) , while another says that the gravitational force of the matter in the universe will cause the expansion to stop and then a period of contraction to start, ending up with all the matter coming together in a 'big crunch'. This second theory creates what is known as a closed universe and people have postulated that the 'big crunch' is analagous to the 'big bang' that started the universe in the first place. In this way we get an infinite cycle of universes, each starting with a bang and ending with a crunch
Re:Ladies and Gentlemen: The Scientific Method (Score:1, Informative)
They almost make it sound like a bad thing (crashing down...) from some old beard who doesn't like all this new-fangled change. If old theories are proven false and new theories are created that more accurately describe our universe, then that's a good thing.
Mod parent up. Parent's parent: read + understand (Score:2, Informative)
A common misconception, with an easy to learn answer.
This answer can then be applied to say that Einstein does not support Ptolemy, as Ptolemy's theory describes motion that does change. In rotating even at a constant rate around a fixed point, the orthogonal ("at right angles") components of the motion (e.g. East-West versus North-South) each oscillate between maximum and minimum values. That's the acceleration. The total magnitude of this acceleration may be constant, but its direction isn't. The reason for it in the case of the planets wasn't even apparent in Kepler's time. It took Newton to find laws which approximately described this effect (his laws of motion and of universal gravitation) and this model was further refined by Einstein with General Relativity published the year after the Special Theory.
The fact is that Kepler had no more sophisticated ideas of the mechanism underlying orbital motion than did Ptolemy. Kepler is better than Ptolemy on the grounds of superficial description of the motion alone.
This is far from an indictment of Kepler, but speaks rather to Kepler's imagination, trust to observation (notably from the perspective of history, Tycho Brahe's data), and willingness to challenge the accepted theory, which authority at the time was backed up by armies and courts of Inquisition.
The late Richard P. Feynman's little treatise "The Character of Physical Law" (MIT Press) is the best introduction to this history, and features Feynman's extrodinarily hilarious expository style, as well as his legendary insistance on accuracy with regard to interpretations of both the various physical theories, and their canonical histories.
I wish to God that Feynman were still with us. Goodbye, Dick, we hardly knew you.
Article by Tom Shanks (Score:2, Informative)
Re:Brief History... (Score:5, Informative)
Just to show another angle (as opposed to the highly doubtful statement that only 7% believe in God), I Googled and found:
In the US, according to a survey published in Nature in 1997, four out of 10 scientists believe in God. Just over 45% said they did not believe, and 14.5% described themselves as doubters or agnostics. This ratio of believers to non-believers had not changed in 80 years. Should anybody be surprised? (from http://www.guardian.co.uk/life/feature/story/0,13
So no, it's not most scientists, as it's mostly half and half (according to Nature/Guardian).
Re:Brief History... (Score:2, Informative)
2. There are people who say they believe in God but not in a personal god. (e.g. Deists)
Re:Umm....OK? (Score:4, Informative)
"Nobody knows for sure whether Dark Matter exists or not. But there are a whole lot of independent reasons to believe it exists, all of which result in very, very similar numbers for how much Dark Matter there is. If the Dark Matter theory is wrong, it's very hard to imagine what else could possibly explain all those numbers, all at once. (It's easy enough to explain one or two of those, but that's not an improvement over current theories, that's a step back.) Dark Matter hasn't made it to 100% certainty, but other theories have a lot to explain if Dark Matter doesn't explain what we're seeing."
I think that's about right. I Am Not A Physicist, but I follow this and generally understand math, so I think I'm at least competent to translate...
(On my own, I'd note that giving how flexible geometry can be, I can easily imagine someone constructing a geometry of the universe that doesn't need dark matter that turns out to be mathematically equivalent to a universe that does have dark matter. I'd give some of the geometry-based theories some time to be vetted by real astrophysicists before assuming they provide a real alternative; they may well just encode the Dark Matter into the structure of the Universe itself, which really isn't an alternate theory, just a restatement of the original in a different form. Until someone produces some Dark Matter, or the Universe is explored to our satisfaction to determine no such matter exists, this may remain unresolvable.)
Re:Correct me if I'm wrong... (Score:5, Informative)
If you set the strength of gravity equal to 1 then the other forces have the following approximate strengths relative to gravity:
Strong nuclear force: 10^40
Electromagnetic force: 10^38
Weak nuclear force: 10^15
Gravity: 10^0
So why is gravity so important if it is so weak? The thing about gravity is that it falls off slowly with distance and it can't be negated or blocked (as far as we know). Other forces are either extremely short-range or, in the case of the electromagnetic force, have both an attractive and repulsive component that tends to cancel out in the long-run.
Re:Brief History... (Score:3, Informative)
In the US, according to a survey published in Nature in 1997, four out of 10 scientists believe in God. Just over 45% said they did not believe, and 14.5% described themselves as doubters or agnostics. This ratio of believers to non-believers had not changed in 80 years. Should anybody be surprised?
(from http://www.guardian.co.uk/life/feature/story/0,13
Re:The stuff doesn't exist. (Score:5, Informative)
Lots of things were done this way. Specifically, Planck's attempt to correct the ultra-violet catasctrophe of black-body radiation theory by quantizing the radiation was a total kludge. The theory matched the data fairly well, which led to a flood of new inquiries, leading to Einstein's description of the 'photoelectric effect' and the birth of quantum mechanics.
The concept of the gyromagnetic ratio, or Lande g factor, for particles was another kludge that can be adequately explained using sufficient detail of Quantum Field Theory.
Even more macroscopic phenomenological theories, like Landau's theory of 2nd-order phase transitions expands the free energy of a physical system in terms of one or more order parameters. That's a kludge and a half, but in many cases adequately describes physical systems close to phase transition points that formal Hamiltonian interaction methods cannot get to.
Extending on this is the Ginzberg-Landau theory using a complex order parameter for superconductors. (Remember Ginzberg just won the Nobel Prize for Physics a few months ago. Landau won it decades ago and would have won it again if he was alive). It was shown by Gor'kov that the BCS theory of superconductivity (ie, formally-applied theory involving Cooper pairs of electrons and superconducting gap) approaches the Ginzberg-Landau expansion at the critical point.
So yes, Kludges are really used all the time in physics, and they're no black eye at all. There's two reasons we need to use these. Firstly - macroscopic systems are just so damn complex one cannot solve a 10^23 dimensional Hamiltonian, that's ridiculous. So even from basic principles complicated order can emerge.
The second reason is that it is quite likely we don't fully know the ultimate physics basic building blocks, just a very good approximation of them. Complicated systems can reveal small perturbations from the standard model that's accepted.
that won't solve everything (Score:3, Informative)
The existence of dark matter has also been inferred from other observations (see above link), but even if that observation doesn't hold up, the odd behavior of galaxies still remains.
That's called science (Score:5, Informative)
Dark matter is simply a theory. If Newtonian mechanics is correct (we don't even need to worry about relativistic corrections here), and the laws of physics are the same everywhere (a fundamental principle of science), then there is a lot more matter than we can see (i.e., that is glowing). We can tell this by looking at the rotation curves of galaxies, and even the behavior of clusters of galaxies. There must be a lot of matter there that we can't see, if Newtonian mechanics is a reasonable approximation. It's called dark matter.
Dark matter in and of itself is really not a revolutionary concept. In most wavelengths of light, for instance, you qualify as dark matter (you emit no visible light, although you do emit infrared radiation, so you're not completely dark matter). Look around your room or office. How many things emit electromagnetic radiation. Your computer and your monitor, sure. Your light fixtures and other electronic equipment either emit light or heat. But most of the stuff around you emits internal radiation. A pen is dark matter. A cup of dark matter (once its reached thermal equilibrium, of course). That book is dark matter. The concept of dark matter is not only not revolutionary and mind-blowing, it's downright mundane. Given the survey of stuff in your office/room, is it any surprise that most of the junk in the Universe doesn't emit radiation on its own?
When we start getting into the weird realms of dark matter is when we start applying the Standard Model and find out that it doesn't seem like all that dark matter can be explained by baryonic matter (basically, protons and neutrons -- what we would normally consider matter). That's where things start getting sketchy and speculative, although we have some theories about what might be responsible. But dark matter in and of itself is simply a consequence of the mediocrity principle (that is, the laws of physics operate elsewhere just the same as they do here) and Newtonian gravitation.
All the popular media's fascination with dark matter is only so much hoopla.
Nice description, except... (Score:2, Informative)
Dark Energy on the other hand is the equivalent of Einstein's Universal Constant. For some unknown reason, the universe is accelerating in its expansion (counteracting the gravity that SHOULD be causing it to slow down), instead of slowing down (and eventually ending in a Big Crunch) as we previously had thought.
Just FYI.Huh? (Score:5, Informative)
it may explain why things can be completely random at a quantum mechanical level, but balance out in larger systems...
It's called the Central Limit Theorem and Superposition. You've got billions of identical particles (low variance), and a huge sample size at macroscopic scales, thus your mean (likelyhood of "expected" things, the precision, and thus "intelligence" in systems) will be pointy as a pin.
I am 100% dead serious.
Perhaps maybe your REAL question is "why are quarks so damned sticky, protons so stable, and h_bar conveniently small?" because that encapsulates the huge gap between the quantum world and the stable world we live in.
Re:what if theory didn't exist? (Score:5, Informative)
You're absolutely correct. If we accepted theory as fact without any repeatable testing it would be religion, not science.
We may never fully understand the nature of our universe, and almost certainly will never understand it in our lifetimes. But the question raised in the topic is actually a fundamental one that spans far beyond dark matter to all forms of theoritical science. Many theories are based heavily upon other theories. The "root" theories (with any luck) will eventually be proven or disproven, affecting all research and theories which follow that "root".
What is important is for scientists to fully understand the theories that they base their work upon, and knowing the risks involved. Not doing so is irresponsible, and can lead to misinformation and confusion.
With the above in mind, it's also important to note that many theories have been disproven throughout and entire scientific disciplines have crumbled around the fall of these theories. However, from those ashes, new disciplines have arisen (the first that comes to mind is chemistry rising from the "ashes" of alchemy). I'm sure that in 100 years, many if our current ideas will be laughable, but this failure has proven fundamental to our growth (how's that for rhetoric!?)
Re:I Wish I Was a Scientist (Score:5, Informative)
(I am an astrophysicist. I am not a cosmologist, but I do galaxy evolution... we hang out with cosmologists)
There are quite a few pieces of evidence for dark matter:
- internal dynamics of galaxies: when you look at how fast the outer parts of galaxies move around the central parts, you find that the amount of mass necessary is much more than what you see
- dynamics of galaxies in clusters: when you look at how fast galaxies move around in galaxy clusters, you find the amount of mass necessary is much more than what you see
- non-linear growth of primordial perturbations (sounds complicated, isn't really): the universe used to be almost completely smooth. now it's filled with clumps of matter like galaxies and clusters and big voids without much matter. the structures collapsed because of their mass. if there were only as much mass as you can see, there hasn't been enough time for galaxies to have collapsed
The amazing thing about all of these measurements is that they all give you the same answer for how much mass is really out there.
[TMB]
Re:Umm....OK? (Score:5, Informative)
Dark matter is implied by several things:
- Galactic rotation curves
- The velocities of galaxies in clusters
- Anisotropy of the Cosmic Microwave Background
I'm leaving out Type Ia supernovae because I don't think they really imply dark matter *by themselves*.Galactic rotation curves: If you have an object that rotates, and you know the velocity as a function of radius, you should be able to get the density as a function of radius. This is obvious, because the velocity is coming from gravity.
The problem: you can also get the density by assuming that light-emitting material carries the majority of the matter (stars - pretty good approximation) and then looking at the luminosity as a function of radius (how bright it is). So, in a perfect world, these two profiles would match.
They don't. Therefore either
- Not all of the matter is light emitting
- Gravity doesn't work.
Option 1 there breaks the least physics, so it's preferred.Velocity dispersion in clusters : See above - just with galactic clusters, rather than galaxies. Note that fixing one of these problems would probably fix the other!
Anisotropy of the CMB : This one's tougher to explain easily. 100,000 years after the Big Bang, the Universe was an extraordinarily uniform big fireball. Extremely uniform - because electrons hadn't cooled enough to form hydrogen yet, so it was one big hot plasma.
When hydrogen cooled, the photons in the Universe suddenly found themselves free to move, because hydrogen can only absorb certain wavelengths, and free electrons absorb continuously. Those photons are the Cosmic Microwave Background. Their uniformity is a very good indicator that the Big Bang theory is real - at least, from 100,000 years after the Big Bang to now.
However, matter that was in that fireball DID distort the radiation slightly - through gravity. And so we see anisotropy (nonuniformity) in the microwave background, and it looks very much like standing waves in the sky. The ratios of the strengths of certain frequencies tell us the ratio of dark energy ("lambda", the cosmological constant) to matter, AND also tell us how "flat" - i.e., how much total energy - the Universe has. It's flat. Exactly. Really really flat. It has exactly as much energy as would be needed to reverse the initial Big Bang (if it were all in matter, which it isn't). And it also tells us that dark energy is 70% of the energy content of the universe, and matter is 30%.
Big bang nucleosynthesis . BBN basically says "you can only get this much normal matter from a big bang explosion cooling to form atoms". It's amazingly accurate so far - it gives great answers for the ratio of certain elements, for instance. But it also puts a stringent limit on the amount of normal matter, of about 5%. The CMB *also* gives this same measurement - and, amazingly! - they agree! There are in fact even OTHER measurements which give values consistent with this number - 5% - so it's hard to imagine how measurements coming from completely different areas of physics (one is standing waves in the early Universe, one is nuclear physics) could give the same answers, and both be wrong. (But Nature can be perverse...)
So, Omega_m has to be about 30%, and Omega_b is about 5%. Plus there has to be something making stars and galaxies rotate too fast. Physicists, wanting elegance, say "two problems, one solution is a great theory."
Basically: If dark matter doesn't exist, we've got a lot of work to do to come up with other models, and a huge amount of it would affect gravity, which we thought we were beginning to understand!
It's very hard to imagine a form of gravity which could answer all of these problems, AND still be consistent with what we observe today.
Haven't they created this stuff in a lab? (Score:3, Informative)
Or is this "dark matter" something different than anti-matter?
Someone please explain, the article is high on fluff but low on details.
Re:SIGGRAPH keynote: geometry instead of dark ener (Score:3, Informative)
I'm reading the presentation at the moment, but my math's a bit rusty (20 years rusty, if truth be told), so I can't comment on it.
Re:Haven't they created this stuff in a lab? (Score:3, Informative)
Re:Ladies and Gentlemen: The Scientific Method (Score:2, Informative)
Rowan Atkinson did a great comedy sketch [rowanatkinson.org] based on a premise a little like that:
Rowan Atkinson plays of course the lead role in BlackAdder and Mr. Bean.
Fourier was a plagerist (Score:2, Informative)
Re:what if theory didn't exist? (Score:5, Informative)
You are mistaken. There have been a number of studies done to try to determine if fundamental "constants" such as the speed of light are in fact constant.
It is, of course, very difficult to devise experiments to test such theories, but a number have been designed and performed. The phrase "no one has bothered to even look" comes up in other fields, such as paranormal research, and it is just as untrue there. Scientists would love to find evidence of (say) the gravitational constant changing, extraterrestrial organisms, or psychic power, and to suggest that they haven't even bothered to look is an insult to the field.
Is Newtonian Gravitation wrong and laughable? (Score:3, Informative)
Theories can never be proved. We will never fully understand the universe. We may develop theories that accurately predict every phenomenon, then the next day, something new could come along and show us we were wrong.
What is important is for scientists to fully understand that theories are always merely theories, not facts.
Re:Ladies and Gentlemen: The Scientific Method (Score:1, Informative)
Yes, in fact, that is indeed the underlying problem with religion. It's unprovable and relies on "faith".
I forget who it was -- it was repeated by Douglas Hofstadter which is where I first read it -- but there is written a brilliant rebuttal of Pascal's theorm. Part of it can be found on the web, in the essay "Is God a Taoist", but it was the addendum to that, which I haven't seen on the web, which rebutted the idea that it's "safer" to believe in God than to not do so. I suggest you seek it out. I believe it was outlined in "Metamagical Themas", though it may be "The Mind'd I", I don't recall.
Re:Correct me if I'm wrong... (Score:3, Informative)
All made-up (Score:4, Informative)
They are all made-up, most likely by someone with Schizotypal syndrome [ffrf.org].
Re:Resistance to change (Score:4, Informative)
No they didn't. I hung out with cosmologists when doing my astrophysics PhD over 10 years ago, and they were considering various mixes of hot and cold dark matter, dark energy, open and closed universes. Flat universe and no dark energy was merely the provisionally accepted most likely solution.
The implied existence of dark energy is revolutionary to cosmology, but it didn't catch people by surprise - they were actively looking for it.
Re:Ah, but it does... (Score:3, Informative)
Which means the purpose of the universe and of ourselves is now ridiculously simple and inane, and furthermore, if we ever figure it out, it won't be replaced. Which is a shame.
Re:I Wish I Was a Scientist (Score:4, Informative)
actually that's newtonian. They use Einstein's theories for gravity now.
Re:Theory. (Score:2, Informative)
Perhaps you misunderstand the position of anti-evolutionists (or creationists). As a creationist, I don't disagree with variation within or without of a species (speciation); that would be intellectual suicide and I'd be foolish to hold to a belief for which scientific evidence proves to be wrong...
But rather, creationists believe that rather than all living organisms having evolved from a single organelle, that in the beginning there was created a number of discrete organisms (kind's). Since then these organisms have changed, been bread into 'purebreads' with specific features, and in some cases speciated to become separate species that can't interbreed with their original 'kind'. So in this model, rather than believing in the upward process of evolution that pushes towards better and better species, we see the organisms in the world degrading (from a genetic point of view) to more 'refined' species. i.e. once a new species how sprung out of it's original 'kind', it no longer has the genetic information in it to climb up the genetic ladder and produce new variation.
I hope this helps explains the creationist position as I find it is something that is often misunderstood. I know that a lot of people will argue that they simply can't accept that there was a number of organisms originally created, but this is an assumption on creationists behalf that we can't prove; just an evolutionists assumption that in the beginning there was nothing is an assumption that they can never prove. All we can do now is scientifically test our hypothesise against observable evidence to see which one seems more correct.
Re:misleading characterizations... (Score:1, Informative)
The first thing that occurs to me upon reading it is that his proposal for sweeping the CMB anisotropies under the rug, the Sunyaev-Zeldovich effect, really isn't an issue in WMAP's lower frequency bands. Even if he's right and the 94 GHz band is slightly contaminated, there remains the four other frequency bands, and those show the same spectrum of anisotropies as everyone else. (WMAP is hardly the first to measure the CMB anisotropies. Check out ACBAR, MAXIMA, CBI, COBE, BOOMERANG, DASI and others and convince me that they all got it wrong too.)
And anyway, the SZ effect is well-understood; a couple large surveys are coming on line in the next couple years that hope to map out galaxy clusters using their SZ signatures on the CMB (APEX-SZ and the South Pole Telescope, for example). Noteably, they're all observing at much higher frequencies (220 GHz, etc) than WMAP.
WRT the large-scale WMAP power spectrum points, the cosmic variance (uncertainty that comes from the fact that we can only observe one universe, rather than a whole ensemble of them) dominates on those scales, so as the WMAP team has pointed out, those points need to be taken with a grain of salt. You can't throw out the concordance cosmological model based on them, certainly.
His point about SNIa evolution is well-taken, to a point, though it's been addressed in some detail by both the Perlmutter and Reiss groups.
Essentially, Shanks's problem boils down to a complaint that we still don't understand dark energy or dark matter, and it would be nice to do away with them. He's right on both counts, but at this point there's too much evidence in their favor to discard them so readily.
Re:Natural selection has been shown, not evolution (Score:3, Informative)
First, my field is MIS. Yes, I've read the posts about worthless MIS profs, and I'm probably one of them. You can reference my many GNU apps I've contributed to OSS. I've contributed patches to several OSS projects, most recently Spyce. I know assembly, C, C++, currently teach Java, python, and a few others. Yes, I've programmed several genetic algorithms for use in real situations. However, I was trained in the scientific method just like other scientists. Most PhDs are very much the same as far as science goes. But no, I'm not a specialist in evolution or biology. I should have been more clear.
I won't nitpick your post. Let me just talk about the mathematics of evolution. I may believe in God, but I am not against evolution. God and evolution are not mutually exclusive, and evolution may just be right. My post said that from a scientific perspective, evolution doesn't seem to hold weight with me.
The human body is a base-4 computer (A,G,C,T). Take one side of DNA, and you essentially have computer code. The human genome project suggests we have about 30,000 genes. While genes is not the same as bits (it's a collection of base-4 "bits", I'll use them for the mathematics.
To get to where we are now, we'd need at least 30,000 mutations (actually quite a bit more) that were useful enough to select over other mutations. If we assume an x percent successful mutation (quite liberal) rate, we'd need x^30,000 mutations.
The universe is believed to be about 13 billion years old. Thats 297648000 billion seconds, or y^17. How many mutations would be required per second to get to x^30,000? Statistically, I just don't see it.
Again, I'm not against evolution from a "God" perspective. I'm against it from a mathematics perspective. Just like any theory, it's useful because it allows us to model the world and understand at some level. I think evolution will be a great step to a more correct theory at some point.
I just get very bothered that people (even some scientists) think evolution is "truth", when science never proclaims to find truth. It's a *theory*.
Newton, Einstein, and others were all shown to be wrong in time, even though their theories were elegant and helped us do wonderful things (like go to the moon, fly, etc.). String theory right now is quite interesting, but it's probably not the final theory either.
Heaven help us! (Score:3, Informative)
(Let us know if someone needs to explain it to you.)
Re:Natural selection has been shown, not evolution (Score:2, Informative)
Ok, so let's assume that there is only
The formula you're really looking for is 30,000/x.
Now, with the correct equation, even if we assume there is only
Please go back and revise your math. And try another approach, this one simply doesn't work.
You're a scientist. I'm 17.
Re:Ladies and Gentlemen: The Scientific Method (Score:3, Informative)
Re:Brief History... (Score:3, Informative)
In 1916, James Leuba sent a survey to 1000 scientists (500 biologists, 250 mathematicians, and 250 physicists/astronomers) drawn randomly from the appropriate sections of the 1910 edition of American Men of Science. Leuba broke his data up between all scientists and "greater" scientists, based on labels of "greater" as listed in his edition of American Men of Science.
Section A had three options, requesting the responder to choose one:
1. I believe in a God in intellectual and affective communication with humankind, i.e. a God to whom one may pray in the expectation of receiving an answer. By "answer" I mean more than just the subjective, psychological effect of prayer.
2. I do not believe in God as defined above
3. I have no definite belief regarding this question.
(There was a B question regarding beliefs in "Personal Immortality" or afterlife I'm not going to elaborate on)
Leuba found 41.8% of all scientists responding answered 1 (belief), 41.5% answered 2 (disbelief), and 16.7% answered 3 (doubt)
Leuba found 27.7% of the "greater scientist" group answered 1, 52.7% answered 2, and 20.9% answered 3.
In 1997, Edward J. Larson and Larry Witham published in Nature ("Scientists are still keeping the faith" [nature.com]) a survey of scientists intended to be similar to Leuba's- a survey of 1000 people drawn randomly from American Men and Women of Science in similar disciplinary proportions using the same question that Leuba used.
Larson & Witham found 39.3% of the 'scientist' group answered 1 (belief), 45.3% answered 2 (disbelief), and 14.5% answered 3 (doubt)
In 1998, Edward J. Larson and Larry Witham published in Nature ("Leading scientists still reject God" [nature.com]) a followup survey of "leading" scientists- in this case, all 517 members of the (US) National Academy of Sciences at the time were sent the survey.
Larson & Witham found 7.0% of the NAS respondants answered 1, 72.2% answered 2, and 20.8% answered 3.
I don't expect a particular bias either way (either of believers being less likely to respond or of nonbelievers being less likely) but it's possible. An argument could be made for either bias.
The 7% figure of the parent post is taken from the second survey, but its description of the body being surveyed as "scientists" would be more valid to use 1997 study. Larson and Witham's estimate for the percentage of scientists(given the limits of their study) who are believers was 39.3%, not 7%. This, however, is still not the "most" claimed by the grandparent.