Cosmology's standard model: is science becoming a belief ?

[Andrew Mason]

Cosmology's standard model: is science becoming a "belief"?

I recently made a partially tongue-in-cheek remark on this board about cosmology being a bit like religion. I thought, being April Fool's day, that I might get away with a provocative post. However, it appears that others did not share my sense of humour and it was removed.

I am not the first person to ask the question, however. So I will ask it in a slightly less provocative matter and see what happens.

Religion is based, at least in part, on a belief in the truth of a theory that cannot be falsified by evidence.

The standard model of cosmology is based on a belief in the truth of a theory that dark matter and dark energy exist and that this drives the expansion of space and the increasing rate of recession of the galaxies. However, all attempts to detect dark matter and dark energy have been proven unsuccessful. Yet cosmologists maintain that the theory is correct and that, perhaps, dark matter and dark energy are undetectable in this universe.

If, in fact, dark matter and dark energy are inherently undetectable in our universe, any theory based on the existence of such phenomena cannot be falsified. Since the basis of all science is the falsifiability of theory, how, then, would a belief in the standard model of cosmology differ fundamentally from a religious belief?

AM

 

[dm4b]

It's anathema to suggest science has anything to do with religion these days, which is why they removed your post, I'm sure.

You couldn't speak your mind in Church, now we can't even talk about the deeper meanings and problems within our theories. It all seems sort of dogmatic to me, whether in science or religion.

But, you raise good points. In addition, theories often start off as beliefs, or as I prefer to say, intuitions.

Our theories today, are moving deeper and deeper into realms that are becoming very difficult, if not impossible, to directly test, with String Theory being the prime example. The extra compactified dimensions may be too small to directly probe/test and prove (in any amount of reasonable time) that they definitively exist. Strings are almost definitely at too high an energy scale to directly test in any forseeable future. We will be left with mostly indirect means to validate the theory.

What does all this say for empiricism in the future? If String Theory is hard to directly test (and assuming it's even correct), how difficult will it be to empirically prove the theory that comes after String Theory? Or, should we not learn from history, and fall into the same trap, by saying we are nearing the end of physics?

 

[Calrid]

Well there is tentative evidence of dark matter such as in the Bullet cluster. So it's not just belief.

I think the problem is some people tend to equate a tentative theory that is popular with a tentative theory that is right. And the fact that other theories aren't aesthetically pleasing as a reason to accept the popular one. It seems this is a contention in science where our reach has exceeded our grasp so we are reaching at things. There is a problem there.

Truth is not a scientific concern, it is a philosophical one. Science tends to approach the truth as a limit it cannot reach as does philosophy.

What does all this say for empiricism in the future. If String Theory is hard to directly test (and assuming it's even correct), how difficult will it be to empirically prove the theory that comesafter String Theory? Or, should we not learn from history, and fall into the same trap, by saying we are nearing the end of physics?

Nothing annoys me about string theory except proceeding to a conclusion without any evidence. I find the sphere worthwhile but the assumptions to be pointless if they are going to proceed to more assumptions; the assumptions based on assumptions become more than even philosophy. This is a house of cards.

And we could just prove the theories that came before too. Nothing says that they are not going to produce an answer, just that their assumptions might be wrong or that we just don't have the whole story.

I think we are nearing the end of what we can do atm empirically. The end of physics not even close, we are approaching a renaissance. Never been a better time to be alive in physics, everything is quite literally up for grabs.

 

[marcus]

...
Our theories today, are moving deeper and deeper into realms that are becoming very difficult, if not impossible, to directly test, with String Theory being the prime example. The extra compactified dimensions may be too small to directly probe/test and prove (in any amount of reasonable time) that they definitively exist. Strings are almost definitely at too high an energy scale to directly test in any forseeable future. We will be left with mostly indirect means to validate the theory.

What does all this say for empiricism in the future. If String Theory is hard to directly test (and assuming it's even correct), how difficult will it be to empirically prove the theory that comesafter String Theory? Or, should we not learn from history, and fall into the same trap, by saying we are nearing the end of physics?

I don't think String is a sign of what theoretical physics is going to be like in the future. If it can't come up with the testables it could eventually be replaced by theories that can.

I agree with Cairid that DM is not just a belief---gravitational lensing can map density contours of DM clouds.

And DE could turn out not to be some kind of energy but simply a constant in the Einstein field equation. A reasonable constant to find on the lefthand (curvature) side of the classical GR equation.
( http://arxiv.org/abs/1002.3966 Why all these prejudices against a constant? )

I find I'm also in general accord with much of the rest of Cairid's post. Thanks for making these points!

Well there is tentative evidence of dark matter such as in the Bullet cluster. So it's not just belief.

I think the problem is some people tend to equate a tentative theory that is popular with a tentative theory that is right. And the fact that other theories aren't aesthetically pleasing as a reason to accept the popular one. It seems this is a contention in science where our reach has exceeded our grasp so we are reaching at things. There is a problem there.

Truth is not a scientific concern, it is a philosophical one. Science tends to approach the truth as a limit it cannot reach as does philosophy.

Nothing annoys me about string theory except proceeding to a conclusion without any evidence. I find the sphere worthwhile but the assumptions to be pointless if they are going to proceed to more assumptions; the assumptions based on assumptions become more than even philosophy. This is a house of cards.

And we could just prove the theories that came before too. Nothing says that they are not going to produce an answer, just that their assumptions might be wrong or that we just don't have the whole story.

I think we are nearing the end of what we can do atm empirically. The end of physics not even close, we are approaching a renaissance. Never been a better time to be alive in physics, everything is quite literally up for grabs.

"at the moment" is an important qualification here.

A corner of the picture to watch is what the early universe phenomenologists are doing. They are professional theory-testers, their job is not to take sides or engage in partisanship but to figure out practical ways to test theories. They sniff out points of vulnerability, if there are any to be sniffed. They win either way (pass or fail) if they can get a test performed.

I recently did this search that turned up 29 early universe phenomenology papers that appeared 2009 or later. This got my attention because it looks like early signs of something happening---a possible test taking shape of one possible resolution of the singularity.
So I'll give you the link to list and you can see what if anything you think about it.
http://www-library.desy.de/cgi-bin/spiface/find/hep/www?rawcmd=FIND+%28DK+QUANTUM+GRAVITY%2C+LOOP+SPACE+OR+DK+QUANTUM+COSMOLOGY%2C+LOOP+SPACE%29+AND+%28DK+primordial%2C+fluctuation+OR+DK+INFLATION+OR+DK+COSMIC+BACKGROUND+RADIATION%29+AND+DATE+%3E+2008&FORMAT=www&SEQUENCE=citecount%28d%29

 

[bcrowell]

I believe in many things that I cannot directly verify empirically, but that are indirectly verified. I believe that the Earth has a core made of stuff like nickel and iron, but I haven't personally studied a sample of it. I believe that mitochondria started out as symbiotes in cells, but I wasn't there when it happened. I believe that a rock dropped on the surface of Pluto will have an acceleration of about 0.7 m/s2, but I haven't been there to test it. I believe that neutrinos have mass, but I've never had an opportunity to put one on a postal scale. I believe in the existence of quarks, but nobody has ever detected a free one.

Religion differs from science because it is not falsifiable, even in principle. Cosmological theories involving dark matter and dark energy are certainly falsifiable.

 

[Chalnoth]

I recently made a partially tongue-in-cheek remark on this board about cosmology being a bit like religion. I thought, being April Fool's day, that I might get away with a provocative post. However, it appears that others did not share my sense of humour and it was removed.

I am not the first person to ask the question, however. So I will ask it in a slightly less provocative matter and see what happens.

Religion is based, at least in part, on a belief in the truth of a theory that cannot be falsified by evidence.

The standard model of cosmology is based on a belief in the truth of a theory that dark matter and dark energy exist and that this drives the expansion of space and the increasing rate of recession of the galaxies. However, all attempts to detect dark matter and dark energy have been proven unsuccessful. Yet cosmologists maintain that the theory is correct and that, perhaps, dark matter and dark energy are undetectable in this universe.

If, in fact, dark matter and dark energy are inherently undetectable in our universe, any theory based on the existence of such phenomena cannot be falsified. Since the basis of all science is the falsifiability of theory, how, then, would a belief in the standard model of cosmology differ fundamentally from a religious belief?

AM

While there are certainly people outside of the cosmology community for whom this is a problem, it is not a significant problem within the community. There are always some who hold dogmatically to their theories despite the evidence to the contrary (e.g. MOND), but they are a strong minority and do not at present have a significant impact on the field.

The standard model of cosmology, on the other hand, is strongly evidence-based, and there is no problem with people following the evidence where it leads.

 

[cristo]

If, in fact, dark matter and dark energy are inherently undetectable in our universe, any theory based on the existence of such phenomena cannot be falsified. Since the basis of all science is the falsifiability of theory, how, then, would a belief in the standard model of cosmology differ fundamentally from a religious belief?

If an observation was made that either dark matter or dark energy cannot account for, then they would be seriously in question. Then, it would be up to theorists to come up with a model that better fits the data, which would then become part of standard cosmology. This is a fundamental difference to religion, where no evidence is needed for a belief.

People have tried to come up with other gravitational models such as MOND, but this (or at least its relativistic generalisation, TeVeS) does not stand up to observation (http://arxiv.org/abs/0901.3932), so dark matter is favoured.

A corner of the picture to watch is what the early universe phenomenologists are doing. They are professional theory-testers, their job is not to take sides or engage in partisanship but to figure out practical ways to test theories. They sniff out points of vulnerability, if there are any to be sniffed. They win either way (pass or fail) if they can get a test performed.

I recently did this search that turned up 29 early universe phenomenology papers that appeared 2009 or later. This got my attention because it looks like early signs of something happening---a possible test taking shape of one possible resolution of the singularity.
So I'll give you the link to list and you can see what if anything you think about it.
http://www-library.desy.de/cgi-bin/spiface/find/hep/www?rawcmd=FIND+%28DK+QUANTUM+GRAVITY%2C+LOOP+SPACE+OR+DK+QUANTUM+COSMOLOGY%2C+LOOP+SPACE%29+AND+%28DK+primordial%2C+fluctuation+OR+DK+INFLATION+OR+DK+COSMIC+BACKGROUND+RADIATION%29+AND+DATE+%3E+2008&FORMAT=www&SEQUENCE=citecount%28d%29

I'm not sure that we need to discuss loop quantum cosmology (again) in this thread. It is not part of the standard cosmological model, and has a long, long way to go. I also don't see that it's testable in the near future.

 

[TrickyDicky]

Much of this has to do with terminology and with using certain terminology that is theory-dependent to name observational facts.

But if we referred to the observational fact without prejudices, we'd just talk about star's orbits not following Newtonian predictions in spiral galaxies, or gravitational lensing density contours off-center or supernovae Ia not as bright as we expected for a given distance.
The common factor of all these observations is that they don't fit within the model that was used at the moment of the observations.

For some people it is evident that these are red alarms for any model that should at least question its validity, instead of that the overwhelming majority of the cosmology comunity would rather accommodate these observations within the model, and to do this one has to do something that is very much used in movies and science-fiction works called "suspension of disbelief" by which anything that helps support the initial assumptions is allowed, whether it is particles that are free to disobey any of the laws the rest of matter obeys, or energies that appear right on the just time in our universe even if the odds against it are huge. Anything before even questioning some assumption.
Now they call these pragmatism, not dogmatism or religion, in view that there are other observations that are indeed accounted for by the model. But of course then why were we told so many times that in science is enough with one observation that is not within the theory to falsify it?. And here enter some semantic games, since the modified models (one advantage of the standard model is that is vey flexible) with the fantastic elements that needed the "suspension of disbelief" do account for the above mentioned observations, they say. And they are right and these are indeed honest people, so you see Andrew, this is not about belief, but rather about a willing suspension of disbelief, please do not spoil the fun.

It is also about deliberately confusing the observational facts with the theory-dependent concepts that are used to accommodate them within the modified model.

BTW, bcrowell, there is a trap in your reasoning, for to believe the Earth's core is made of nickel and iron you do not need to postulate the existence of magic stuff or add free parameters to the existing physical theory.

 

[Chalnoth]

But if we referred to the observational fact without prejudices, we'd just talk about star's orbits not following Newtonian predictions in spiral galaxies, or gravitational lensing density contours off-center or supernovae Ia not as bright as we expected for a given distance.

This isn't referring to observational fact without prejudice. This is referring to observational fact without bothering to try to understand it. What you have just described here wouldn't be science at all, in other words.

The common factor of all these observations is that they don't fit within the model that was used at the moment of the observations.

Except they do in nearly every case. Those few areas where there may be some discrepancy are fraught with systematic uncertainties that are very difficult to control.

 

[TrickyDicky]

This isn't referring to observational fact without prejudice. This is referring to observational fact without bothering to try to understand it. What you have just described here wouldn't be science at all, in other words.

I see. So to you the first step of the scientific method which is the collection of observations is not science at all. That's curious. But goes well with your idea that there is only one way to understand the observations :the standard one. All very scientific indeed.

 

[Chalnoth]

I see. So to you the first step of the scientific method which is the collection of observations is not science at all.

No, I'm saying that stopping at the collection of observations isn't science.

 

[TrickyDicky]

No, I'm saying that stopping at the collection of observations isn't science.

And why would you want to stop there?

 

[Chalnoth]

And why would you want to stop there?

You seemed to imply that we should in your post.

 

[TrickyDicky]

You seemed to imply that we should in your post.

I didn't.
Perhaps what I unconsciously implicitly implied is that it is forbidden by the rules of the forum to speculate or as you put it "to try to understand the observations" outside the standard model. In that sense, sure, there is a serious stop there, but certainly it's not me who is enforcing it.

 

[Jamders]

I recently made a partially tongue-in-cheek remark on this board about cosmology being a bit like religion. I thought, being April Fool's day, that I might get away with a provocative post. However, it appears that others did not share my sense of humour and it was removed.

I am not the first person to ask the question, however. So I will ask it in a slightly less provocative matter and see what happens.

Religion is based, at least in part, on a belief in the truth of a theory that cannot be falsified by evidence.

The standard model of cosmology is based on a belief in the truth of a theory that dark matter and dark energy exist and that this drives the expansion of space and the increasing rate of recession of the galaxies. However, all attempts to detect dark matter and dark energy have been proven unsuccessful. Yet cosmologists maintain that the theory is correct and that, perhaps, dark matter and dark energy are undetectable in this universe.

If, in fact, dark matter and dark energy are inherently undetectable in our universe, any theory based on the existence of such phenomena cannot be falsified. Since the basis of all science is the falsifiability of theory, how, then, would a belief in the standard model of cosmology differ fundamentally from a religious belief?

AM

even they may be undetectable today chances are that later on our imperfect instruments gona be better and the same way religion was proven wrong many times (we are not the center of the universe, this planets i round not flat just coz those times telescopes did not exist) Not want to said any thing about Gods and creators coz it can be wrong as well. Open minded as Christopher Columbus was make him who discover america at the time he did, For sure it was not him, later one someone else would. navigation was advancing and was a fact unavoidable.

 

[TrickyDicky]

even they may be undetectable today chances are that later on our imperfect instruments gona be better and the same way religion was proven wrong many times (we are not the center of the universe, this planets i round not flat just coz those times telescopes did not exist) Not want to said any thing about Gods and creators coz it can be wrong as well. Open minded as Christopher Columbus was make him who discover america at the time he did, For sure it was not him, later one someone else would. navigation was advancing and was a fact unavoidable.

What are you talking about?
An effort is asked around here to articulate a minimally coherent discourse.

 

[Jamders]

What are you talking about?
An effort is asked around here to articulate a minimally coherent discourse.

are following the thread a little bit ? I think u did not

 

[Chalnoth]

I didn't.
Perhaps what I unconsciously implicitly implied is that it is forbidden by the rules of the forum to speculate or as you put it "to try to understand the observations" outside the standard model. In that sense, sure, there is a serious stop there, but certainly it's not me who is enforcing it.

The reason why this forum attempts to limit discussion to scientifically-validated theories is simply because if this is not done, discussion tends to rapidly devolve into repeated back-and-forth around crackpot theories that have no relevance to reality whatsoever. This forum does not prevent discussion surrounding any theories that are taken seriously within the scientific community.

The suppression of crackpot nonsense does nothing but improve the signal-to-noise ratio of the forum. It doesn't put any significant limits on the discourse that have any relevance to reality.

 

[cristo]

This forum does prevent discussion surrounding any theories that are taken seriously within the scientific community.

I think you mean does not!

 

[Chalnoth]

I think you mean does not!

Yes, fixed it :)

In my defense, I was (and am) exceedingly tired.

 

[Andrew Mason]

I believe in many things that I cannot directly verify empirically, but that are indirectly verified. I believe that the Earth has a core made of stuff like nickel and iron, but I haven't personally studied a sample of it. I believe that mitochondria started out as symbiotes in cells, but I wasn't there when it happened. I believe that a rock dropped on the surface of Pluto will have an acceleration of about 0.7 m/s2, but I haven't been there to test it. I believe that neutrinos have mass, but I've never had an opportunity to put one on a postal scale. I believe in the existence of quarks, but nobody has ever detected a free one.

Why do you have to "believe" these things? The scientist would say, we can never prove anything in science so all I can say is that based on currently available evidence it is likely that: a) the Earth core is mainly iron and nickel; b) mitochondria started out as symbiotes in cells; c) a rock dropped on the surface of Pluto will have an acceleration of about 0.7 m/s2; d) neutrinos have mass; and e) nucleons are made up of quarks which are fundamental particles. It seems to me that if one has a belief that these are, in fact, true, one goes a little beyond science into the realm of faith: faith that the current model, of whatever it is, will not be falsified in the future.

If a late 19th Century scientist believed in the existence of the luminiferous aether I don't think it would be unfair to say that this was a belief based on entirely on faith. It was not a belief based even in part on evidence since there was no evidence that ether existed. There was just a theory. The scientist could have said: "I do not understand how a wave could propagate through space without a medium of some kind; so I postulate that there is a luminiferous aether present throughout all of space."

Religion differs from science because it is not falsifiable, even in principle. Cosmological theories involving dark matter and dark energy are certainly falsifiable.

I would not say that Cosmology is not a science. It tries to be a science. And it could be a science if cosmologists would stick to scientific principle. Cosmological theories can be falsified by observations but not by experiment. The problem then is how to interpret the observations. It may be a plausible theory that all Type Ia supernovae in the universe have roughly the same absolute luminosity. But it has not exactly been subjected to the kind of testing that, say, quantum electrodynamics has been subjected to. To rely on those kinds of theories to reach a "belief" in the origin, present state and future state of the universe goes beyond science, I would suggest.It would be scientific to say: "we do not really understand how the universe began, how it got to be the way it is and where it is going but based on the evidence available the best guess as to what happened is contained in the standard model. In the end, we really don't understand it and this theory may be quite wrong, but at present it is the best guess that we can make". Anything beyond that is not science. It is a bit like religion.

AM

 

[Chalnoth]

I would not say that Cosmology is not a science. It tries to be a science. And it could be a science if cosmologists would stick to scientific principle. Cosmological theories can be falsified by observations but not by experiment. The problem then is how to interpret the observations. It may be a plausible theory that all Type Ia supernovae in the universe have roughly the same absolute luminosity. But it has not exactly been subjected to the kind of testing that, say, quantum electrodynamics has been subjected to. To rely on those kinds of theories to reach a "belief" in the origin, present state and future state of the universe goes beyond science, I would suggest.

It would be scientific to say: "we do not really understand how the universe began, how it got to be the way it is and where it is going but based on the evidence available the best guess as to what happened is contained in the standard model. In the end, we really don't understand it and this theory may be quite wrong, but at present it is the best guess that we can make". Anything beyond that is not science. It is a bit like religion.

This is pure, unadulterated ********. Cosmology today is as much a science as anything else out there. Throwing up your hands and saying, "We don't know and can never know," is the diametric opposite of science. Blatantly ignoring the evidence that we have collected, as you are doing here, is the diametric opposite of science.

The strength of the science surrounding the current standard cosmological model lies in the high level of consistency between a wide variety of observations, not in anyone type of observation alone. There are likely to be some biases in the supernova studies, for example, but they are relatively minor and other observations don't have the same biases. Throwing out the supernova data altogether is not the right answer to this: checking the result with other, independent data sets is.

 

[jtbell]

Closed pending moderation decision.