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What If Dark Matter Really Doesn't Exist?
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.'"
So what if it doesn't really exist? We know very little about anything anyway. Trying to find a unified explanation via "String Theory" is spotty at best but at least it "helps".
What's the difference if dark-matter is really just another false theory? In the long run it's not going to make a whole heck of a lot of difference.
If something else is actually causing those effects, the whole theoretical edifice would come crashing down.
As it should.
-Colin
Much like a dog staring at a shiny object, I'm fascinated by this but I don't understand it.
It's a theory. Theories can be wrong.
Jedi don't stand a chance.
HAD
It will be interesting to see how scientists who have staked their entire careers upon the existence of dark matter would react to the discovery that it does not in fact exist. Ideally an invalid theory is dropped, and a new, more "correct" theory is created. However, I have a feeling that a lot of people have invested too much time and effort into dark matter to let it go without some serious evidence.
My patience is infinite, my time is not.
Actually, with Einstein's relativity, doesn't Ptolemy's theories hold true? Everything is relative to a point of view?
Sorry I didn't ask this question in Modern Physics's class. It was a morning class, and I was sleeping.
...but doesn't String Theory tend to suggest that "dark matter" isn't actually dark matter, but instead is gravitation bleeding from other universes? The same theory also explains why gravity in this universe is so weak. Because most of it bleeds of into other universes via the higher dimensions, it's weak enough for you and I to move our limbs.
Javascript + Nintendo DSi = DSiCade
Are planes going to drop from the sky? Will we be thrown out of orbit? This sounds like the Bugs Bunny cartoon where Bugs floats on air because he never studied the laws of gravity (I know I've probably got the reference wrong, but you get the idea).
Your experiment fits the model, or it doesn't. If it doesn't then one or both need to be tweaked, or scrapped.
We don't understand something fully? Wow... that's about as brilliant as deciding to cut my sandwich in triangles instead of in squares.
The truth is this. We have such a little understanding of actually governing laws that we can't begin to fathom it. However, that doesn't stop us in progression to learning. Just because this theory might not be right (and probably isn't) doesn't mean we are any less an idiotic species. We've been working on these theories for many millenia. One of them turning out to be wrong won't be a surprise... it's a probability. Without the wrong hypthosesis, we can never stumble onto the correct ones. Its Edison's, "Every time I fail, I know one more way how to NOT build it" idea.
"What If Dark Matter Really Doesn't Exist?"
Then wait for Star Trek to invent a new theory.
"Derp de derp."
...then 99.9999999% of the world won't notice. But it will be on CNN anyways.
You're right, I wouldn't steal a car. But if it were possible, I sure as hell would download one!
There seem to be growing "hints" that something is wrong with current theories about the very nature and behavior of gravity. This includes alleged dark matter that cannot be identitied, planetary space probes with slight deviations from expected sun "pull" [1], and the fact that there is no identifiable "negative" gravity while the other forces do have negative values or particles.
[1] It was originally thought that heat generated from nuclear fuel cells was "pushing" the probes, but this was mostly ruled out because the heat lessens over time, but the pull was constant.
Table-ized A.I.
Science has been progressing on the basis of constantly proving theories as kludges and bringing about something newer and more real. Imagine if our currently held view was true (before Standard Model), we will never be able to travel faster than light, we'll never harness energy bigger than a hydrogen bomb, we'll never really travel far beyond the Solar system, travel back in time etc.
Before the cannon was invented everyone thought the arrow was the greatest weapon, and few could really predict the power of "Little Boy" on Hiroshima. Quantum Mechanics has given us so much hope, of unknown and unexplainable realities, and that far more is possible than we first thought. It means the road before us is much longer, but far more interesting. I'd prefer it that way.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
Dark matter had better exist- otherwise, I've wasted a hell of a lot of money on that dark matter damage insurance I bought a couple years back...
Gentlemen, you can't fight in here! This is the War Room!
Then I can walk down the hall in the middle of the night without fear of stepping on my little boy's building blocks.
Hey, all the better!
If the end of the universe is a heat death it might be possible to live forever, in smaller increments of time/energy. If the universe crunches, everyone and everything dies...
'Sensible' is a curse word.
It's more than that. If Dark Matter doesn't exist, we will be forced to re-examine more than just our current picture of the universe. Galactic Rotation curves, velocity dispersions of galaxy clusters, the flatness of the universe implied by the CMB, type Ia supernovae data, as well as other distance indicators, all imply that the parameter "Omega_mass" (the mass density of the universe divided by the critical density) is about 0.3. If there is no "dark matter", we don't know how to explain this number. Baryons, i.e. stars, planets, gas, etc., make up only an "Omega" of 0.044 +/- 0.009. This constraint is from Big Bang Nucleosynthesis and is very strong. Although there are plenty of open questions about dark matter, it seems to me (just an astrophysics grad student) that there is an overwhelming amount of evidence for not only dark matter, but the model of "cold" dark matter as well. None of the alternatives can explain even half of what Dark Matter can, including modifying gravity. Plus, Dark Matter is consistent with GR, the big bang, and everything else we hold dear about physics and astronomy, whereas other theories don't. Just my two cents... Ethan
There is some intriguing evidence of the existence of strange quark matter, a dark matter candidate, which we've recently published in the Bulletine of the Seismological Society of America. as previously discussed on /.
Dark Matter will be taught to school children as the Aether of 21st century science.
You keep telling yourself that... God boy. However only 7% of scientists believe in a personal god.
There's nothing wrong with a kludge, aesthetics aside. Every evolving line of discovery needs it's necessarily flimsy connectors of reason. It's only when we allow our pride/ignorance/greed etc. to deny that the kludge is just a kludge: this is where mistakes are made, and thus we fail to evolve.
The fact that the universe may not boil down to 3 categories of matter is not earth-shattering. If we discover something to the contrary we must look at it plainly.
The problem with kludges is that it's only a kludge when it's a theory that is revealed to be inherently flawed. Before this realisation, it's just the best theory we have at our disposal. Just because something is revealed to be inelegant doesn't mean it wasn't serviceable, or simply the limit of our reason at the time it was presented.
This wasn't just plain terrible, this was fancy terrible. This was terrible with raisins in it. - Dorothy Parker
The keynote speaker at the 2003 SIGGRAPH conference in San Diego was the British astrophysicist Anthony Lasenby. He claimed that a new kind of unified Euclidean and hyperbolic geometry could explain acceleration and deceleration in the Big Bang. He was talking at SIGGRAPH because his new unification of geometry is supposed to be more elegant for computer graphics modeling than the current homogeneous coordinates now used. He wrote a book about the geometry. But I have been unable to find a paper relating to the cosmological application on the web.
This is not the first time geometry has been used to unify and simplify physics. Previous examples are Galilean coordinates, special relativity, and general relativity.
Actually, most Physicists don't believe in God.
--Keeping the flame wars alive, one post at a time
Bringing this up without mentioning M.O.N.D. is irresponsible journalism. MOND (Modification of Newtonian Dymanics) is a theory that simply says that gravity 'decays' at a slightly different rate than expected over astronomical distances. The effects predicted by this theory are spot on to the observed effects that dark energy and matter try to explain.
I googled about found this link, but I first read about it in New Scientist about a year ago.
The parent is either the most insightful thing ever posted, or the biggest bunch of doubletalk crap I've ever read.
Would someone please translate this and tell me what the hell is being said?
Overrated / Underrated : Moderation
well, let's see here. 4% of postulated matter in the universe is known to exist. 96% of postulated matter in the universe is NOT known to exist. that's a fine fudge factor to have in a test, and might explain where budget figures come from in the government :-D
:-D
it certainly explains where a lot of my assignments come from at work, lol
if this is supposed to be a new economy, how come they still want my old fashioned money?
At the risk of feeding the trolls...
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.
Looks like we're gonna have to stick some moldy olives in a freshly-killed goat and bury it in the sand for 48 weeks. Then we dig it up and soak it in the blood of a 3rd-born virgin girl. If the goat's eyes turn pink, God will give Lyndon Larouche syphilis, if they turn purple, dark matter exists. It's not the cleanest proof, but I say we give it a shot.
I may be showing a few gray hairs here, but revolutions in the sciences have occurred in my lifetime with scientists adapting fairly well. The first was the acceptance of Big bang in the late 1950s. Between 1927 and 1955 the Big Bang was just one of several "equally attractive alternative theories" which included the eternal-infinite universe and continuous creation of matter. The microwave background and the abundance of helium brought the big bang into the fore front.
In the 1960s the quark unification of subatomic particle became the predominate theory. Plus quantum electrodyanamics was verfied in high energy experiments to extremely high precision.
Also in the 1960s plate tectonics replaced an up-and-down explanation of geologic forces.
If the evidence suggests a more powerful theory, then physicists will revise their theories again. Science does not stay attached to incorrect theories (though block-headed individuals do).
I may be incredibly naive, but it has always bothered me that we insist on believing there are only 4 types of force in the Universe, each operating on widely different scales. Why can't there be other forces that operate on too large a scale or too small a scale for us to observe? Is the postulate of "dark force" effectively a theory about a fifth type of force?
"Freedom means freedom for everybody" -- Dick Cheney
First claim: Analyses of the WMAP data on the cosmic microwave background (CMB) show correlations with galaxy clusters that indicate the official analyses of the data are wrong. I find this highly unlikely. First, the effect of the hot gas in those galaxy clusters on the CMB is well known - it is called the Sunyaev-Zeldovich effect and perturbs the spectrum in a well-known way. Second, the official fits to the WMAP data use a consensus cosmology model with about 12 free parameters to fit a dataset of more than a hundred points... beautifully. Third, the consensus cosmology itself has been built up out of a huge array of other observations (supernova distances; Big Bang nucleosynthesis; the "weighing" of galaxies and galaxy clusters; the age-dating of globular clusters), all of which were pointing to the existence of dark matter (even within our own Galaxy!) long before WMAP was even launched. Fourth, modern theories of particle physics also give us good reason to expect the existence of dark matter particles, independent of any astronomical observations whatsoever. So WMAP has simply been the final nail in the coffin, and anyone who wants to overturn dark matter and dark energy has a great deal of additional work ahead of them.
Second claim: Measurements of the masses (actually, the luminosities and temperatures) of high-redshift galaxy clusters indicate a high fraction of baryonic mass, removing one of the justifications for positing dark matter. This finding is even more fishy-sounding. To understand this, realize that the group in question has deliberately chosen the most-distant and therefore hardest-to-study clusters to study, and adopted temperature-mass relationships that are calibrated in the local universe (and may not apply at these great distances) in order to find that their sample differs from the standard model predictions. Without even bothering to list all the ways in which they might be wrong, let me simply state that even if they are right there is a lot of independent support for the dark matter + dark energy picture that neither of these groups is addressing.
Rather than distract yourself by trying to figure out why the carefully constructed consensus cosmology might be wrong, then, I think it is more useful to examine the remarkable ways in which it has been proven right in the last few years. Altogether it is truly a wonder of the modern world - even if it may at some point be shown inadequate to the universe we live in.
-renard
Same idea here. Kepler's laws reduced a nightmarish tangle of mathematics to a three line "program", if you will. Out current model of how various things in our universe interact requires a degree in cosmology to fully grasp, and a PhD to do any meaningful work in. Imagine reducing that to one chapter of a freshman-level physics or astronomy course.
Einstein's Special and General Relativity, Maxwell's Equations, and Schrodinger's Equation are all expressed in a few lines of equations. But you need extensive math and physics training to relate them to the familiar world around us. Simple doesn't mean easy. Theoretical physicists are already busily looking for theoretical formulations in which dark matter and dark energy arise naturally, rather than as a kluge. Of course, if the original observations turn out to have been misinterpreted, they may be wasting their time.
As a scientist, I'm sure you can completely explain this mathematically, as a scientist should.
Oh wait, you're not a scientist. Oh well.
Sometimes it's best to just let stupid people be stupid.
From your article: "60% responded...", "half replied...". In other words, a self-selecting survey. Demonstrates nothing.
Don't blame me, I didn't vote for either of them!
This is misleading because you mention that only 7% of scientists believe in a personal god but you don't bother to mention what "personal god" means. A personal god is one that interacts with / cares about each individual. Many scientists believe in the God that created the universe and set it in motion, but does not interact with each person directly.
... but I play one on TV.
So:
"If dark matter doesn't exist, there will be a lot of erasers sold to the astrophysics department of your friendly neighbourhood university"
DG
Want to learn about race cars? Read my Book
But kludge's are the black eye of science, and even really bright people can make them (remember Einstein and his cosmological constant?).
To be fair, the cosmological constant was a constant that emerged naturally from the derivation of General Relativity, with no indication of what its value should be. To apply it to reality, some value had to be assumed or determined. The simplest thing to do would have been to arbitrarily give it a value of zero, but that would have implied an expanding universe. In the absence of evidence for expansion, Einstein chose to give it a value that made the universe static.
In particular, dark matter, though incredibly mysterious, is probably on firm enough ground that it will withstand a series of challenges. Galactic rotation curves and measurements of cluster temperatures both give very strong evidence for dark matter on vastly different scales; in addition, it is difficult (OK, fine: downright impossible in standard Einsteinian gravity) to get any kind of structure to form *at all* in the universe if one is only allowed to use the visible matter. The precise ratio of dark to visible is definitely up in the air; and, of course, there are competing models that modify gravity -- if these matured enough (they may already have -- I haven't kept up) to make predictions on a wider range of scales, they might work as well.
Indeed, a lot of gravity modifications (extra dimensions, etc.) behave *phenomenologically* as if there was dark matter -- so all the effort we've put into simulating dark matter may not be in vain after all, even if Einsteinian four dimensional spacetime is not the name of the game.
In contrast, indeed, is the exact count of the "baryons" (ordinary matter.) I would be very surprised if we were off by a factor of (lets be ultra-conservative here) five in the baryon number, which is constrained very well by big bang nucleosynthesis, whose predictions remain in the "ordinary" realm of nuclear explosions. Something we know a little about.
The real mystery is "dark energy." There, the evidence is a lot shakier. It rests on a few pillars. There is a theoretical bias that wants the universe to be flat (so that the missing mass-energy is made up for by some dark energy component that doesn't cluster and affect our galactic rotation curves.) There are some really excellent (but difficult) measurements of universe acceleration, a signature of dark energy, from people who observe distant supernovae (these provide "standard candles" that allow you to measure distance given an apparent brightness.)
Finally, there are the CMB measurements, which provide a similar kind of distance measurement, but are open to alternative interpretations (instead of measuring apparent brightness, they measure apparent angular size -- but it is perhaps possible, if you squeezed around, to construct a different model where the apparent angular size is squished in odd ways.)
And then there are a host of other measurements that one might call more "marginal" (without prejudice to the people who work very hard to do them -- I aspire to be one of them.) They rely on a few more astrophysical assumptions, and perhaps would not convince the slashdot skeptic. (My profound apologies if I've missed out someone's awesome measurement.)
One big "trouble" is that we haven't seen good evidence for a very particular signal that one would associate with the simplest model of dark energy. (This is the "low quadrupole" -- the news stories you read about finite universes are from people who, in part, are motivated by the desire to explain this low quadrupole signal by other means.) Of course, it is entirely possible to make more exotic dark energy models that don't show this signal (I've coauthored a paper on one such model), but that missing signal, gosh, damn.
The Economist is usually good with science articles, but it really kind of missed the point on this one. Shanks et al. are not "bringing down the whole edifice"; they are pointing out what they see as a possibly problematic signal in the CMB data. This may inspire in some a little additional -- and very healthy -- skepticism about the dominant models. But it is important to mention that there really is no "dark energy mafia"; nearly any astrophysicist worth his or her salt would drop dark energy like a stone if the evidence started piling up, and many, many astrophysicists keep a hand in alternate models that don't rely on dark energy because, hey, what a scoop that would be.
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How many scientists believe in God?
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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).
At least they have observations. And astronomers in general are a genial bunch. Anyone who finds (and this is the most likely case) that there is dark matter, but not nearly enough of it, is assured of nothing more that a few years of ostracism before enough new scientists come into the field who don't have the same emotional investment in dark matter theories.
Compare that to the potential fate of the poor wretch who disproves the Riemann Hypothesis, and undoes almost all progress in pure mathematics since the beginning of the 20th century. I know for a fact that there is a basement in Cambridge where this person will live out their days being forced to review unsolicited "proofs" of duplicating the cube, trisecting the angle, and squaring the circle.
--
E_NOSIG
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.
make world, not war
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.
Let me clarify what I mean by that. As I see it, one of the main goals of science is satisfying our curiousity. The mission of science (or one of the missions to be precise) is to learn about nature so that everyone who is eager to know why things are the way they are can learn and understand.
However, the way the physical science has been progressing lately, the more we "learn" about the universe, the farther we are from our goal. Before 20th century, the scientific knowledge could be explained to anyone, you didn't need any complex formulas, almost any law of physics could be explained in simple terms. People indeed could learn and understand.
Now look at what science has become. In order to understand field theory, or cosmology, students study for 10 years in school, then 4 years in college, then several more years in grad. school and only then they start getting a grasp at what this whole thing is, and start to understand how it all works.
It is practically impossible now for anyone except a very small group of very specialized people to understand the recent theories in physics. We seem to discover new things every day but noone understands them except a few chosen.
I remember that Einstein used to say in the beginning of the 20th century that in the 21st century special relativity will seem just as obvious and normal to every kid as steam engine was to kids back then. Yet today, I am a graduate student in physics, and I cannot claim to really understand special relativity, I only understand how to use the formulas to predict how things behave.
I think the way things stand now, science is failing one of its most important missions. We no longer understand our universe. All we do is learn how to predict the behaivor of things with greater and greater precision, which is very useful and all, but we are getting further and further from _understanding_ the universe which really is the inpiration of science.
Human history becomes more and more a race between education and catastrophe.
H.G. Wells, "The Outline of History"
Entire careers in physics are going straight down the shitter because of dark matter, because it doesn't exist. From the very first time I read about it, I thought "Geez, this sounds like a 3 year old trying to cover up the fact that he doesn't KNOW the reason why".
Uh.
The primary evidence for dark matter is that if you look at how galaxies move and how clusters of galaxies move, they should all be flying apart. They are moving too fast for the amount of gravity we calculate by adding up all the mass of the stars and the gas that we can see. Since galaxies and clusters are around all over the place, we know they're not falling apart. Ergo, there must be more gravity than can be accounted for from the material we can see.
The simplest, easiest, and most direct explanation is that there is more there than we can see. Matter not emitting light, thus called dark matter. There's nothing kludgy or ad-hoc about this, it's the most natural conclusion to make. The alternative is that Newtonian Gravity (or General Relativity, which has Newtonian Gravity as a limit in the relevant case)-- that theory which perfectly predicts the motions of planets, spacecraft, apples, and other things that we have lots of experience with-- must be wrong. There are people who believe this over Dark Matter, in fact, but to me, "stuff there that we haven't found yet" seems to be a much more likely and plausible explanation.
The evidence for why the dark matter can't all be baryonic (i.e. made up of "normal" stuff) is more indirect, but it comes out of other theories for the construction of the elements in the hot early Universe-- and this other theory itself has made predictions that match well what was observed.
-Rob
There is no decent explaination... emergent intelligence...
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.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
> Evolution, OTOH, has never been demonstrated or shown in an experiment. To demonstrate evolution would require watching a planet from start to finish, which we have not yet done.
Sorry to inform you, but science allows indirect evidence as well.
> Something not taught in school that should be is that evolution is dependent upon natural selection, but not the other way around. The earth could have been populated by God/Aliens/someone creating species in a test tube somewhere and populating the earth. Natural selection would just as easily occur with this hypothesis.
You seem to be confused about the subject matter. It is correct to say that it doesn't matter whether gods/aliens/naturalforces/blindchance created life, because evolution could operate on the result regardless of the origin. All evolution requires is imperfect self-replicators.
> BTW, I'm a scientist
You certainly don't talk like a scientist. What is your field, and where can we find a list of your publications?
> WRONG. There is no such thing as proving a theory right (i.e. as truth).
And a real scientist would know that scientists don't spend their time trying to "prove" theories right. Rather, scientists look for explanations for observed phenomena, and theories are the product of that endeavor.
> Evolution is so mathematically improbable that I'm surprised that most scientists just accept it.
Can you show us the math on that?
> It's a great theory to explain things right now (which is why we use it), but there's a good chance it will probably be proven false someday.
Can you show us the math on that, too? (I'll gladly accept "it may be proven false someday", but you are asserting more than that, even with your double qualification. What are the chances that the theory of evolution will be proven to be false some day?)
Sheesh, evil *and* a jerk. -- Jade
Welcome to the world of neuro-bio! Whoever built our brains didn't know jack about maintainability. They're a bloody mess! Unused functions left around from previous versions. Disabled features. Appalling code reuse. Oh sure, there are some beautiful optimizations, and the system architecture has a certain elegance -- but the implementation is crap.
If an omniscient power built us, I hope He/She wrote in a high-level language and then compiled with some heavy optimizations turned on (-oGOD?). If They were hand-rolling this shit, I'd like to have a word or two with Them.
You take the facts, come up with a working theory that fits the facts. As more facts come in, you continue to test your theory against the facts. When too many anomolies show up, it's time to come up with a new theory.
And there is nothing wrong with that. Is Newtonian physics worthless just because it couldn't explain everything? No, but we had to be willing to look for new answers when we began to see evidence that the old answers didn't work for everything we observe. It's called a paradigm shift.
Check out Thomas Kuhn's Structure of Scientific Revolutions
** The opinions expressed here are my own, and do not reflect those of my employers - past, present, or future**
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.
oh brave new world, that has such people in it!
However in this case your comment is only slightly wrong and therefore I have some hope that my reply might be a useful contribution.
You are correct that mathematical proofs are based on axioms. However there is still a crucial difference between a mathematical proof and a scientific theory. A mathematical proof is an absolute certainty. Note that I am not claiming that the underlying axioms are certain. I am only claiming that the proof itself is certain.
To put it another way, mathematicians are never certain about their underlying axioms but they are absolutely certain that if those axioms hold then the result stated in the proof also holds. It's kind of like a building with indestructible walls but no foundation.
Scientific theory is a whole different kettle of fish. You cannot prove a scientific theory with absolute certainty. In fact it is not even clear to me how one can define certainty within the framework of the scientific method. You never have any guarantee in science that future observations will be consistent with past observations.
In science you can prove a theory in the sense of preponderance of the evidence. You can even sometimes prove a theory beyond all reasonable doubt. But there is no way to eliminate the unreasonable doubts. Any endeavour based on empirical observation suffers from the fundamental limitation that you can never be sure of the next observation.
Finally, regarding 1+1=2, the foundational proof of this fact using the standard propositional axioms of mathematics really does require 362 pages. You can see the 362nd page on the bottom half of this Russell's paradox site.
Not laughable, and still usefull, even if it is 'wrong.' It is still 'right' in most circumstances, and we know what those circumstances are. We know when to use it as a good enough approximation, and when we need to use more accurate theories.
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.
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
It seems to me that a central tenet of Christianity is the Good News itself -- that an actual guy actually taught a bunch of people how to be good to each other, and actually came back from the dead. That is (at least in principle) a physical, provable proposition, and finding things like the shroud of Turin is a big part of that. Other religions work the same way -- there're a core set of beliefs that hold in the physical world, and that are thought to be supporting evidence for some metaphysical beliefs.
It also seems that this thread is pretty far afield from the topic of cosmology. Religion and physical cosmology are somewhat orthogonal.
"Sure, one can argue that if two theories are functionally equivalent, there's no downside to taking the simpler one. But has anyone demontrated this logically or mathematically?"
It's really a postulate, an unprovable given. If the 2 theories are really functionally equivalent you must accept the simpler. The more complex one only wins if it can explain behaviour that the simple one can't. Then they aren't really equivalent, are they?
Assume for the moment that Einstein's physics and Newton's physics are functionally equivalent. Einstein's is more complex. If both came out in Newton's time, Einstein's would have to be rejected. Einstein's explains many things that Newton's doesn't - but back then they didn't realize that those things needed explaining. The only thing that could be pointed to then that Newton's didn't capture is slight misprediction of the orbit of Mercury. I'm not sure they could even measure it's orbit accurately enough to detect the misprediction back then. Not really good enough for Einstein to be percieved as more than a crank.
As time goes on more and more evidence accumulates that Einstein can explain and Newton can't. They become less and less equivalent.
-- your Web browser is Ronald Reagan
Let's say our limited perspective from our solar system were somehow enhanced by a telescope/sensor at a neighboring solar system. Wouldn't this give us a much more accurate map of the universe than our current narrow view? For all we know most of the matter might not be visible because something is standing between us and it. The very fabric of space gets distorted by the weak gravitational field of our small star and each and every bit of matter floating around out there and we believe that larger gravitational forces exist, like black holes. If we can't even completely understand how and why our star warps the fabric of space how can we expect to KNOW the universe and all the matter contained within it?
We don't understand the laws of this universe. We've barely been able to explain it with simple mathematics. The universe, for all we know, might require higher mathematics than the human brain can easily comprehend. And what if there are other universes? But what do I know, I'm just one small voice in this titanic harmony-challenged choir. I'm sure one day someone with a lot of money will figure it out and tell all of us about it in an infomercial late at night on TV.
They are all made-up, most likely by someone with Schizotypal syndrome.
Help fight continental drift.
1) Pascal's wager doesn't work - lots of religions make countervailing or contrary claims to being correct. The question that most people have to decide is not whether to have faith in anything or not, but whether to believe in Christanity or Hinduism or Judaism or Islam or... Many of these choices are exclusive or contradictory, so believing in something won't necessarily save you - only believing in the right thing will. In addition, believing in something excludes options from the here and now - if you hold a religious belief, you must act consistently with it, excluding some possible actions that might benefit you. Pascal's Wager is not cost-free, and since its benefits are unclear (if all beliefs lead to the same place, Pascal's wager holds; if some beliefs lead to Hell (or some other bad place) then the value of choice may be much smaller and on the order or the cost of choosing and the opportunity costs of actions you cannot do), it isn't really a very good argument for religious belief.
2) Science and religion are not exclusive unless one forces them to be. Science takes a pragmatic view of the world - what effects we can observe or measure are those of consequence to science. The immeasureable is not science's purview. Religious beliefs ask different, perhaps broader questions: What are we doing here? What do we do with our lives? How does everything work? Science can be considered a subset of this. Multiple religious beliefs may be consistent with a physical phenomenon - the things that distinguish them exist in a place science can't get to and thus has no legitimate say in. The problems occur when religious and scientific claims occupy the same ground and are contrary. In this case, science usually wins because it can be tested, whereas religion depends upon claims that cannot be tested (but which can only be trusted).
In my opinion, it is not the "anti-religionists" who have betrayed us, but a subset of religionists. Religion and science have existed side by side for some time and were not considered inconsistent. In the last few hundred years, some religious folk have tried to "prove" their beliefs by misusing logic and science to their ends (creationism/intelligent design/creation science, for example). Trying to prove the unprovable only further hardens the demands of people for proof before they will believe, undercutting the faith; after all, if the people who claim to most strongly believe something require proof to believe in it, how much faith can they really have? There is also the bonus of trying to force people to have a faith whose value derives from chosen belief (thus destroying the object of belief for others). In addition, the likely purpose of the logical legerdemain (to compel others to behave as one would like) only serves to alienate those who would otherwise be quietly accepting of the faith of others. Vehement (and sometimes illogical) people who don't believe in religion probably come at least in part from this.
Well, it turns out that parent was responding to this:
which is certainly an attack -- it's a charge of dishonesty. Mild by /. standards, but also typical fare for this site. So, yes, there was an attack.
I think this severely misunderstands the state of Christian thought. If you look at the work of, for example, J.P. Moreland or Alvin Plantinga, you will see that they do not appeal to God as an explanation for the inexplicable. Instead, they believe in God because they believe that the evidence points firmly in that direction.
I teach science: H.S. Chem and Physics. I have a driving desire to learn, and I try to spark in my students a driving desire to learn and to analyze carefully, critically, and honestly. I also am an evangelical Christian (to use a loaded, ill-defined term) with an (additional) academic background in theology. I guess I would fit your description of the scientist who does believe in a God. So I have no problem with your suggestion that science and Scripture might converge on "God" as the "final answer to the Theory of Everything", and I heartily endorse your suggestion that science can give us a greater understanding of God. Indeed, I teach my students to think that way.
The problem I have is that you portray scientists as neutral pursuers and purveyers of knowledge. They aren't. It turns out (speaking philosophically here) that everyone has a prior notion of the answer to the "does God exist?" question. This is why the question has been and continues to be unresolved philosophically. Our prior judgment on that question entirely colors our judgment as to what "counts" as proof of God's existence. It's a vicious circle, and philosophers have been unable to untangle it.
Scientists are no exception to the rule, and it comes out in all sorts of ways. For instance, take Richard Dawkins, chair of the "Public Understanding of Science" at Oxford. He has written extensively promoting evolutionary thought. So far, a seemingly neutral scientific question, right? But his books contain not only an scientific defense of evolution, but also several defamatory comments about Christianity. It turns out that he integrates his scientific worldview with his atheistic worldview, and uses his position to promote both simultaneously. And so it goes in the world at large. No man is a neutral player on the "God question"; no evidence is ever evaluated without a priori judgments as to how much proof is enough proof. That is where "faith" comes in. For careful thinkers, Faith is not a substitute for evidence. Instead, it is a willingness to evaluate a certain amount of evidence in favor of God's existence, over agains
Human being (n.): A genetically human, genetically distinct, functioning organism.
Well, if Dark Mmmmatter doesn't exist, we'll have to rethink gravity, won't we?
:-)
IMO (very humble indeed) the Dark Matter theory looks more like a shortcut, a quick patch than a solid sound theory. Yes, it fits the observed facts, but probably just because from how little we know right now, we can safely fill in the huge blanks with the right numbers. Those blanks are easy to be filled because they're totally unobservable.
I read something very interesting on gravity in deep space. A scientist who revised the rules of gravity so that the model worked without all this invisible stuff around. The amazing thing is that while this guy does exactly the same as dark matter believers - filling in blank spots until the model fits reality - he's not taken seriously at all.
While I as a non-scientist will just have to wait and see until someone explains it weally well in small words, I am betting 10 to 1 on a revision of the general theory of gravity.
Who's in?
I think, therefore I am...I think.
This thread misses an important point. Even though Ptolemy's theory was wrong, it was a lot closer to the truth than previous ideas like "the lights in the sky are gods with flashlights." The point is that even theories that are wrong add to our knowledge by providing a starting place for deeper inquiries.
Or, an acronym, actually.
MOND = Modified Newtonian Dynamics
It's one of those theories that sounds totally crackpot when you first hear it (and, admittedly, has some problems), but many would argue that it's no weirder than a bunch of dark stuff that we know nothing about. The destain with which astronomers and physicists view MOND is quite surprising, since they are asking us to be believe that (something like) 95% of the matter in the universe is composed of some sort of weird, non-Baryonic particle (most people favor WIMPs over MaCHOs now-a-days).
Anyway, just food for thought.
I couldn't tell if you were experimenting with poor-man's cryogenics or looking for the orange sherbet.
That's so incredibly wrong, I don't even know where to begin. Fourier sequences are about transformation into the frequency domain. Epicycles are about imaginary circles.
This should be modded "funny"