No, you don't. But it's really funny watching you lecture a scientist on what science is.
A prediction can be made about any observation which wasn't used in making the prediction. It doesn't matter whether the data was taken before or after the prediction was made, as long as the prediction doesn't use that data.
Please explain a method "The Theory of AGW" uses to predict a future observation (ie: an equation), and then we can examine its skill at predicting it.
You use a climate model, ranging from a simple energy balance equation to a GCM fluid dynamic simulation.
These models have only existed for a couple decades, so it's hard to test their skill on future data, especially since it takes a couple decades for a climate trend to rise above the noise in the system. But for one example, see here. They find agreement of modeled and observed temperatures but disagreement with sea level rises, probably due to the fact that none of the IPCC TAR models had ice sheet mechanics (just thermodynamics). You can also look up the 1988 projections for Hansen's GISS Model II.
P.S.: There is no "The Theory of AGW'. There are a variety of related theories, each represented by a different model.
There are an infinite number of equations that can fit any finite set of past observations.
You're concerned with overfitting vs. generalization. As I said, this is not a problem if you're not actually tuning the prediction to the past observations. GCMs aren't tuned to, say, the observational surface temperature time series, or stratospheric cooling trends, or the diurnal temperature trend. They are tuned to some things, e.g., the Earth's observed radiation balance at the top of atmosphere, and then they are asked to predict other things they weren't tuned to, like global temperature, precipitation, ocean heat, and ice trends.
The only evidence there can be that you have an equation that shows skill, is predicting data that was unavailabe during its formulation,
Yes, exactly. Which is why you withhold data from the model when it makes its prediction, and test it against the withheld data. That's how cross validation works. Certainly it's nice to have the luxury to be able to compare against future observations, but that's difficult when the system response is slow and noisy. It is incorrect, however, to claim only forecast skill is an indicator of predictive skill. Hindcast skill is an indicator as well, as long as you predict and validate with separate data sets.
Much of our surgical tech. CAME from those experiments.
Hardly. Almost all of the Nazi medical experiments were surgically useless. AFAIK, they didn't invent any new surgical techniques. They did learn a few things about how long humans can survive under extreme conditions, but that's about it, and it didn't even lead to much in the way of new treatments. I think hypothermia may have been an exception. Most of their experimentation was just sadism of little medical or scientific value, and a lot of it was biased to "prove" various Nazi racial theories.
Our knowledge of a number of diseases certainly came from there.
Again, not really. They experimented with drugs/cures for various diseases. They didn't discover any new diseases, didn't discover anything about how the diseases work inside the body, and as far as I know, didn't lead to cures for any major disease.
Binding energy is not invariant. The energy released in a moving frame is different than in the rest frame. If you can't look inside the composite particle, you attribute this difference to kinetic energy of the particle. (From an "assembling constituents" perspective, this is because the energy required to assemble a stationary composite from stationary constituents is different from the energy required to assemble a moving composite from stationary constituents.) If you can look inside, you attribute it to a mix of kinetic and potential (binding) energies of its constituents.
All mass-energy equivalence says about invariance is that E^2 - (pc)^2 is independent of inertial frame, where E and p are the total energy and momentum of the system. In a relativistic interacting system, the potential energy by itself is never invariant, even though it contributes to the total mass(-energy). It's only the sum that is invariant.
I think it is probably true that everything in classical mechanics has a quantum mechanical analogue, since classical mechanics is just a special case of QM (the hbar->0, decoherent limit).
For "relativistic mass" to be true you would need, for example, the binding energy of the quarks in a proton to change when its moving fast...which would be in direct violation of one of the postulates of relativity: "the laws of physics are the same in all inertial frames".
That postulate of relativity doesn't prevent energy from being different in different frames. Many physical quantities are different in different frames (the most obvious is velocity). The invariance postulate of relativity doesn't mean that all physical quantities are Lorentz-invariant. Energy is not. (Rest energy is, for massive bodies.)
However, there are other reasons not to use relativistic mass. One is that you can't apply it everywhere in the force equation F=dp/dtau. For motion parallel and perpendicular to the velocity of the body, you have to use different masses (longitudinal and transverse mass), and in general you have a mass matrix. So it's not a universal concept that can be substituted everywhere Newtonian mechanics uses mass. Of course, neither is invariant mass, but all the other kinds of mass can be fundamentally written in terms of it.
This could be a disagreement over the meaning of the word "classical". Physicists often mean "non-quantum", but sometimes they mean "Newtonian".
A hotter body is more massive than a cooler body in relativistic, non-quantum ("classical") physics. This is because kinetic energy contributes to mass via E=mc^2.
In Newtonian mechanics (no quantum mechanics and no relativity), this is not the case.
The effect discussed in TFA is not inherently a quantum effect. It is a relativistic effect. Field energy as well as the mass of matter contributes to the total mass of a bound system. (In Newtonian mechanics, field energy contributes to the total energy of a bound system, but not the mass, because there is no mass-energy equivalence.)
I can't see a way in quantum electrodynamics for pair/anti-pair production to be analogous to acceleration radiation. Consider the reverse process, pair annihilation. That can take place even with two particles at relative rest and with zero instantaneous acceleration. The energy of the resulting photon is independent of the particles' accelerations, and is in fact a constant if the particles are at rest.
Classical Maxwellian electromagnetism is compatible with quantum theory since it's the formal classical limit of QED, but that doesn't mean that everything in QED has a classical analogue.
This is how I recall it: if dark matter was baryonic, then the early universe would have produced a lot more helium and less deuterium. Deuterium has 1 proton and 2 neutrons; helium has 2 protons and 2 neutrons. If there are a lot of extra baryons (protons and neutrons) around, it's easy for them to collide with existing deuterium atoms and produce helium. I think...
Also, if there are a lot of baryons around, I think the early universe doesn't "clump" enough to produce the superclusters and things we see today. I think this is because the dark matter doesn't interact electromagnetically and so is able to start clumping earlier. The cosmic background radiation is an independent check, because the non-baryonic "clumping" is also visible in fluctuations in the CMBR where denser matter affected the local radiation — non-baryonic clumps could already exist and grow by the time the CMBR was formed (~400,000 years after the Big Bang).
Don't take everything I say as 100% correct; I can't remember all the details of how this works.
I think I misunderstood your argument. I thought you were saying that a peak at 650 GeV is statistically indistinguishable from a background peak at 800 GeV. After re-reading it a couple of times, it looks like you're saying that the signal is distinguishable from background at 650 GeV where it peaks, but not at 800 GeV.
Space can expand at any rate, including faster than light. The FTL restriction is on matter/energy moving through space. It is not a restriction on the geometry of space itself.
As for where the estimated age comes from, your own link answers that.
Now there are valid hypotheses rooted in conventional physics that explain galaxy motion and other astronomical observations and don't depend on dark energy/dark matter
Name one that agrees with all the observations as well as dark matter does. And I mean ALL the observations, not just one particular set of observations that the theory happens to do well on. Science has to be consistent with all available evidence, not just the evidence you cherry pick.
So shouldn't the longest distance to the far "edge" be 13.8 billion light years
No, because spacetime is curved and the expansion rate is neither constant nor equal to the speed of light.
The misconception is that the Big Bang was an explosion of matter into space, and there is some volume of space with matter in it and some volume outside of which no matter has yet reached.
In modern cosmology, the Big Bang is an expansion of space. There is no center or edge of the universe (although there is an edge of the universe we can see, because light hasn't yet reaches us from farther), and matter is distributed more or less uniformly everywhere in space. More details in this FAQ.
Anyway, how can we go from that size to estimate how old it is? Because they expect it to expand at light speed?
They look at the relationship between how far away objects are and how fast they're moving (via Doppler shift). This gives them the expansion history of the universe. Farther objects are older. Also, the structure of fluctuations in the cosmic microwave background radiation left over from the early universe depends on how the universe has expanded between then and now. When combined with the general relativity theory of cosmology and how the universe expands, you can back out an age estimate.
Savain isn't a creationist, but he is a well-known physics crackpot. He's been promoting his B.S. for over a decade; just search the 1990s archives of the Usenet sci.physics.* groups. He emotionally can't accept the mathematical notion of spacetime, because he claims that "nothing can move in spacetime", which only proves that he misunderstands the whole concept. (Thus his claim above that physicists have been unable to explain the concept of "movement".) He usually then proceeds with long, profane rants against various respected physicists. You know you're on the receiving end of a classic Savain rant when he starts raving about "chickenshit voodoo physicists".
I can't get past the paywall to see how many sigmas they put on the detection event, but I seriously doubt the situation is as simple as you claim. I personally find it unlikely they would get published in Nature with a signal that is statistically indistinguishable from background noise. Unfortunately, I can't read the paper to see what they did. I'm not a particle astrophysicist, but you don't mention at all what the error bars are; a 150 GeV difference can be big or small depending on how precise the measurement is. The location of the peak is also not the only factor which you can use in detection; the height and shape of the I(E) curve matters, as well as the time signature (light curve). Quite possibly they found a real source. Whether that source is dark matter is another issue.
It could be an asteroid belt of non-glowing rocks. That would totally count according to the definition, and is actually one of the more likely explanations of what 'dark matter' really is.
No, it isn't. It's not baryonic at all (made of protons and neutrons); if it was, that would have produced ratios of elements in the Big Bang which disagree with the ratios we observe.
And anyway, it's all based on some mathematical calculation of how much mass they think is floating around in space. If the math is wrong, the whole thing could be a complete fantasy.
We have a good idea of how much mass is floating around in stars, and in gas, and in dust, and now even in dark bodies like brown dwarfs. The estimate could be off, but it's not off by the factor of 10 necessary to get rid of the need for dark matter. And it's not just the amount of matter, it's the distribution of matter that matters. In order to get the observed galactic rotation curves, matter has to be distributed in a particular way. If there's more mass out there, but it's distributed in the same way as what we see, it doesn't work. Either way, there "missing mass" which is out there unaccounted for.
In time they will discover what is causing the effects of this 'dark matter' - it will not be super strange matter, nor another form of matter, but will be either a change in the overall calculations of our universe's energy
"Calculations of our universe's energy" don't have anything to do with the fact that gravitational orbits don't look right. There are basically only two posibilities: there is an unseen source of gravity, or gravity doesn't work the way we think. Both options have been explored, and the first agrees best with all the data.
or it will be some type of substance that was not accounted for.
You mean some unknown substance which we haven't been able to see, but which affects orbits... like, I don't know, "dark matter"?
There are already strong constraints on what kind of substance dark matter can be. It's not large dark objects like brown dwarves and black holes; those would have been seen in microlensing surveys. (Indeed, some were seen, but not nearly enough to account for the observed gravitational effects.) It's not ordinary baryonic matter (made of protons and neutrons) at all; that would have completely altered the ratio of elements created in the Big Bang to something we don't observe. It's not light particles like neutrinos; "hot dark matter" doesn't consistently explain all the observations like how galactic and supercluster structure was seeded in the early universe. For these and many other reasons, the evidence points toward it being a massive weakly interacting particle. Such particles have already been theorized to exist in particle physics for other reasons, e.g., to solve the strong-CP problem in the Standard Model or to explain the hierarchy problem or grand unification. Indeed, it's somewhat hard to write down a theory beyond the Standard Model that doesn't naturally include a dark matter candidate.
LSU physics doesn't suck. They have 8 faculty working on aspects of general relativity, whereas most departments don't even have one — due partly to their proximity to the LIGO gravitational wave observatory.
Scientists looked at the data and saw it didn't fit, so they made up some goofy theories that "explained" why their calculations didn't match reality.
Yeah, uh, DUH. That's what science IS. You make up a theory to describe what you observe. If it doesn't fit, it's wrong, so you make up a new one and see if that works.
As another poster said, you seem to have some kind of ideological prejudice against the particular theory they came up with. But it's foolish to criticize them merely for coming up with a new theory in the first place. That's what they're SUPPOSED to do.
No! My theory isn't WRONG! It's... err... invisible matter that can't be detected in any manner!! Yeah! That's the ticket!
So you're mocking the idea that there can be particles out there which don't interact with light, despite the fact that we know such particles exist, e.g., neutrinos? The main difference between neutrinos and dark matter is that dark matter needs to be heavier than neutrinos. And dark matter particles have been PREDICTED to exist for entirely independent reasons in order to explain other mysteries in particle physics; indeed, the Standard Model itself arguably already contains dark matter candidates (axions). According to you, this is an insane idea to be derided, despite the fact that its predictions agree with numerous observed phenomena including galactic rotation curves, galactic cluster orbits, large-scale structure formulation, cosmology and the CMBR, gravitational lensing, galaxy collisions, etc.
I define it the way everybody else in the global warming debate defines it: "natural" changes are the ones that can't be directly attributed to human activity, specifically fossil fuel emissions and other anthropogenic alterations in atmospheric constituents, as well as land use changes and the like. Of course, attribution requires some theory, because we have to postulate a counterfactual, namely what the climate would have been like in the absence of this activity. And attribution has to include feedback effects (atmospheric warming which melts ice which changes the Earth's albedo and leads to more warming).
If you to make some pointless "but humans are part of nature" distinction, fine, but it's not advancing the discussion anywhere. The question of what climate changes can be attributed to, say, industrial fossil fuel emissions is independent of how you define the word "nature".
Slashdot Mirror
You don't seem to know what a prediction is then.
No, you don't. But it's really funny watching you lecture a scientist on what science is.
A prediction can be made about any observation which wasn't used in making the prediction. It doesn't matter whether the data was taken before or after the prediction was made, as long as the prediction doesn't use that data.
Please explain a method "The Theory of AGW" uses to predict a future observation (ie: an equation), and then we can examine its skill at predicting it.
You use a climate model, ranging from a simple energy balance equation to a GCM fluid dynamic simulation.
These models have only existed for a couple decades, so it's hard to test their skill on future data, especially since it takes a couple decades for a climate trend to rise above the noise in the system. But for one example, see here. They find agreement of modeled and observed temperatures but disagreement with sea level rises, probably due to the fact that none of the IPCC TAR models had ice sheet mechanics (just thermodynamics). You can also look up the 1988 projections for Hansen's GISS Model II.
P.S.: There is no "The Theory of AGW'. There are a variety of related theories, each represented by a different model.
There are an infinite number of equations that can fit any finite set of past observations.
You're concerned with overfitting vs. generalization. As I said, this is not a problem if you're not actually tuning the prediction to the past observations. GCMs aren't tuned to, say, the observational surface temperature time series, or stratospheric cooling trends, or the diurnal temperature trend. They are tuned to some things, e.g., the Earth's observed radiation balance at the top of atmosphere, and then they are asked to predict other things they weren't tuned to, like global temperature, precipitation, ocean heat, and ice trends.
The only evidence there can be that you have an equation that shows skill, is predicting data that was unavailabe during its formulation,
Yes, exactly. Which is why you withhold data from the model when it makes its prediction, and test it against the withheld data. That's how cross validation works. Certainly it's nice to have the luxury to be able to compare against future observations, but that's difficult when the system response is slow and noisy. It is incorrect, however, to claim only forecast skill is an indicator of predictive skill. Hindcast skill is an indicator as well, as long as you predict and validate with separate data sets.
Much of our surgical tech. CAME from those experiments.
Hardly. Almost all of the Nazi medical experiments were surgically useless. AFAIK, they didn't invent any new surgical techniques. They did learn a few things about how long humans can survive under extreme conditions, but that's about it, and it didn't even lead to much in the way of new treatments. I think hypothermia may have been an exception. Most of their experimentation was just sadism of little medical or scientific value, and a lot of it was biased to "prove" various Nazi racial theories.
Our knowledge of a number of diseases certainly came from there.
Again, not really. They experimented with drugs/cures for various diseases. They didn't discover any new diseases, didn't discover anything about how the diseases work inside the body, and as far as I know, didn't lead to cures for any major disease.
Binding energy is not invariant. The energy released in a moving frame is different than in the rest frame. If you can't look inside the composite particle, you attribute this difference to kinetic energy of the particle. (From an "assembling constituents" perspective, this is because the energy required to assemble a stationary composite from stationary constituents is different from the energy required to assemble a moving composite from stationary constituents.) If you can look inside, you attribute it to a mix of kinetic and potential (binding) energies of its constituents.
All mass-energy equivalence says about invariance is that E^2 - (pc)^2 is independent of inertial frame, where E and p are the total energy and momentum of the system. In a relativistic interacting system, the potential energy by itself is never invariant, even though it contributes to the total mass(-energy). It's only the sum that is invariant.
You may be thinking of this work, also reported in New Scientist.
A factor contributing to its weak magnetic field is probably that Venus rotates very slowly (its day is 243 earth days).
I think it is probably true that everything in classical mechanics has a quantum mechanical analogue, since classical mechanics is just a special case of QM (the hbar->0, decoherent limit).
I propose a more drastic Resolution to the problem.
For "relativistic mass" to be true you would need, for example, the binding energy of the quarks in a proton to change when its moving fast...which would be in direct violation of one of the postulates of relativity: "the laws of physics are the same in all inertial frames".
That postulate of relativity doesn't prevent energy from being different in different frames. Many physical quantities are different in different frames (the most obvious is velocity). The invariance postulate of relativity doesn't mean that all physical quantities are Lorentz-invariant. Energy is not. (Rest energy is, for massive bodies.)
However, there are other reasons not to use relativistic mass. One is that you can't apply it everywhere in the force equation F=dp/dtau. For motion parallel and perpendicular to the velocity of the body, you have to use different masses (longitudinal and transverse mass), and in general you have a mass matrix. So it's not a universal concept that can be substituted everywhere Newtonian mechanics uses mass. Of course, neither is invariant mass, but all the other kinds of mass can be fundamentally written in terms of it.
This could be a disagreement over the meaning of the word "classical". Physicists often mean "non-quantum", but sometimes they mean "Newtonian".
A hotter body is more massive than a cooler body in relativistic, non-quantum ("classical") physics. This is because kinetic energy contributes to mass via E=mc^2.
In Newtonian mechanics (no quantum mechanics and no relativity), this is not the case.
The effect discussed in TFA is not inherently a quantum effect. It is a relativistic effect. Field energy as well as the mass of matter contributes to the total mass of a bound system. (In Newtonian mechanics, field energy contributes to the total energy of a bound system, but not the mass, because there is no mass-energy equivalence.)
I can't see a way in quantum electrodynamics for pair/anti-pair production to be analogous to acceleration radiation. Consider the reverse process, pair annihilation. That can take place even with two particles at relative rest and with zero instantaneous acceleration. The energy of the resulting photon is independent of the particles' accelerations, and is in fact a constant if the particles are at rest.
Classical Maxwellian electromagnetism is compatible with quantum theory since it's the formal classical limit of QED, but that doesn't mean that everything in QED has a classical analogue.
we don't know of any uncharged fundamental matter particles (yet)
Neutrinos?
This is how I recall it: if dark matter was baryonic, then the early universe would have produced a lot more helium and less deuterium. Deuterium has 1 proton and 2 neutrons; helium has 2 protons and 2 neutrons. If there are a lot of extra baryons (protons and neutrons) around, it's easy for them to collide with existing deuterium atoms and produce helium. I think ...
Also, if there are a lot of baryons around, I think the early universe doesn't "clump" enough to produce the superclusters and things we see today. I think this is because the dark matter doesn't interact electromagnetically and so is able to start clumping earlier. The cosmic background radiation is an independent check, because the non-baryonic "clumping" is also visible in fluctuations in the CMBR where denser matter affected the local radiation — non-baryonic clumps could already exist and grow by the time the CMBR was formed (~400,000 years after the Big Bang).
Don't take everything I say as 100% correct; I can't remember all the details of how this works.
I think I misunderstood your argument. I thought you were saying that a peak at 650 GeV is statistically indistinguishable from a background peak at 800 GeV. After re-reading it a couple of times, it looks like you're saying that the signal is distinguishable from background at 650 GeV where it peaks, but not at 800 GeV.
Space can expand at any rate, including faster than light. The FTL restriction is on matter/energy moving through space. It is not a restriction on the geometry of space itself.
As for where the estimated age comes from, your own link answers that.
Sheesh. Grow a clue.
"The theory passes numerous observational tests" != "ZOMG science is religion!!1!!".
Now there are valid hypotheses rooted in conventional physics that explain galaxy motion and other astronomical observations and don't depend on dark energy/dark matter
Name one that agrees with all the observations as well as dark matter does. And I mean ALL the observations, not just one particular set of observations that the theory happens to do well on. Science has to be consistent with all available evidence, not just the evidence you cherry pick.
So shouldn't the longest distance to the far "edge" be 13.8 billion light years
No, because spacetime is curved and the expansion rate is neither constant nor equal to the speed of light.
The misconception is that the Big Bang was an explosion of matter into space, and there is some volume of space with matter in it and some volume outside of which no matter has yet reached.
In modern cosmology, the Big Bang is an expansion of space. There is no center or edge of the universe (although there is an edge of the universe we can see, because light hasn't yet reaches us from farther), and matter is distributed more or less uniformly everywhere in space. More details in this FAQ.
Anyway, how can we go from that size to estimate how old it is? Because they expect it to expand at light speed?
They look at the relationship between how far away objects are and how fast they're moving (via Doppler shift). This gives them the expansion history of the universe. Farther objects are older. Also, the structure of fluctuations in the cosmic microwave background radiation left over from the early universe depends on how the universe has expanded between then and now. When combined with the general relativity theory of cosmology and how the universe expands, you can back out an age estimate.
Savain isn't a creationist, but he is a well-known physics crackpot. He's been promoting his B.S. for over a decade; just search the 1990s archives of the Usenet sci.physics.* groups. He emotionally can't accept the mathematical notion of spacetime, because he claims that "nothing can move in spacetime", which only proves that he misunderstands the whole concept. (Thus his claim above that physicists have been unable to explain the concept of "movement".) He usually then proceeds with long, profane rants against various respected physicists. You know you're on the receiving end of a classic Savain rant when he starts raving about "chickenshit voodoo physicists".
I can't get past the paywall to see how many sigmas they put on the detection event, but I seriously doubt the situation is as simple as you claim. I personally find it unlikely they would get published in Nature with a signal that is statistically indistinguishable from background noise. Unfortunately, I can't read the paper to see what they did. I'm not a particle astrophysicist, but you don't mention at all what the error bars are; a 150 GeV difference can be big or small depending on how precise the measurement is. The location of the peak is also not the only factor which you can use in detection; the height and shape of the I(E) curve matters, as well as the time signature (light curve). Quite possibly they found a real source. Whether that source is dark matter is another issue.
It could be an asteroid belt of non-glowing rocks. That would totally count according to the definition, and is actually one of the more likely explanations of what 'dark matter' really is.
No, it isn't. It's not baryonic at all (made of protons and neutrons); if it was, that would have produced ratios of elements in the Big Bang which disagree with the ratios we observe.
And anyway, it's all based on some mathematical calculation of how much mass they think is floating around in space. If the math is wrong, the whole thing could be a complete fantasy.
We have a good idea of how much mass is floating around in stars, and in gas, and in dust, and now even in dark bodies like brown dwarfs. The estimate could be off, but it's not off by the factor of 10 necessary to get rid of the need for dark matter. And it's not just the amount of matter, it's the distribution of matter that matters. In order to get the observed galactic rotation curves, matter has to be distributed in a particular way. If there's more mass out there, but it's distributed in the same way as what we see, it doesn't work. Either way, there "missing mass" which is out there unaccounted for.
In time they will discover what is causing the effects of this 'dark matter' - it will not be super strange matter, nor another form of matter, but will be either a change in the overall calculations of our universe's energy
"Calculations of our universe's energy" don't have anything to do with the fact that gravitational orbits don't look right. There are basically only two posibilities: there is an unseen source of gravity, or gravity doesn't work the way we think. Both options have been explored, and the first agrees best with all the data.
or it will be some type of substance that was not accounted for.
You mean some unknown substance which we haven't been able to see, but which affects orbits ... like, I don't know, "dark matter"?
There are already strong constraints on what kind of substance dark matter can be. It's not large dark objects like brown dwarves and black holes; those would have been seen in microlensing surveys. (Indeed, some were seen, but not nearly enough to account for the observed gravitational effects.) It's not ordinary baryonic matter (made of protons and neutrons) at all; that would have completely altered the ratio of elements created in the Big Bang to something we don't observe. It's not light particles like neutrinos; "hot dark matter" doesn't consistently explain all the observations like how galactic and supercluster structure was seeded in the early universe. For these and many other reasons, the evidence points toward it being a massive weakly interacting particle. Such particles have already been theorized to exist in particle physics for other reasons, e.g., to solve the strong-CP problem in the Standard Model or to explain the hierarchy problem or grand unification. Indeed, it's somewhat hard to write down a theory beyond the Standard Model that doesn't naturally include a dark matter candidate.
LSU physics doesn't suck. They have 8 faculty working on aspects of general relativity, whereas most departments don't even have one — due partly to their proximity to the LIGO gravitational wave observatory.
Scientists looked at the data and saw it didn't fit, so they made up some goofy theories that "explained" why their calculations didn't match reality.
Yeah, uh, DUH. That's what science IS. You make up a theory to describe what you observe. If it doesn't fit, it's wrong, so you make up a new one and see if that works.
As another poster said, you seem to have some kind of ideological prejudice against the particular theory they came up with. But it's foolish to criticize them merely for coming up with a new theory in the first place. That's what they're SUPPOSED to do.
No! My theory isn't WRONG! It's ... err... invisible matter that can't be detected in any manner!! Yeah! That's the ticket!
So you're mocking the idea that there can be particles out there which don't interact with light, despite the fact that we know such particles exist, e.g., neutrinos? The main difference between neutrinos and dark matter is that dark matter needs to be heavier than neutrinos. And dark matter particles have been PREDICTED to exist for entirely independent reasons in order to explain other mysteries in particle physics; indeed, the Standard Model itself arguably already contains dark matter candidates (axions). According to you, this is an insane idea to be derided, despite the fact that its predictions agree with numerous observed phenomena including galactic rotation curves, galactic cluster orbits, large-scale structure formulation, cosmology and the CMBR, gravitational lensing, galaxy collisions, etc.
You can solve the helium atom via quantum Monte Carlo without a supercomputer, but yes, the problem rapidly grows intractable.
I seriously would like to know how you define it.
I define it the way everybody else in the global warming debate defines it: "natural" changes are the ones that can't be directly attributed to human activity, specifically fossil fuel emissions and other anthropogenic alterations in atmospheric constituents, as well as land use changes and the like. Of course, attribution requires some theory, because we have to postulate a counterfactual, namely what the climate would have been like in the absence of this activity. And attribution has to include feedback effects (atmospheric warming which melts ice which changes the Earth's albedo and leads to more warming).
If you to make some pointless "but humans are part of nature" distinction, fine, but it's not advancing the discussion anywhere. The question of what climate changes can be attributed to, say, industrial fossil fuel emissions is independent of how you define the word "nature".