What causes the research interest in cosmology?

[marcus]

I just happened to notice a way to gauge the degree of research interest in cosmology---which I think has something to do with its importance in uncovering new physics.

What this does is search Stanford's Spires HEP database for the overall most highly cited physics papers that have appeared since year 2000.

http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+TOPCITE+%3D+3000%2B+and+date+%3E+2000&FORMAT=www&SEQUENCE=citecount%28d%29

So the question would be, how do you explain the fact that jumps out here. Cosmology used to be a small, comparatively quiet field. Now it is huge.
Here is how the list goes:

1) First year Wilkinson Microwave Anisotropy Probe (WMAP) observations: Determination of cosmological parameters.
By WMAP Collaboration (D.N. Spergel et al.). Feb 2003. 20pp.
http://arxiv.org/abs/astro-ph/0302209
Cited 5351 times

2) Review of particle physics. Particle Data Group.
By Particle Data Group (S. Eidelman et al.). 2004.
Cited 4273 times

3) Review of Particle Physics.
By Particle Data Group (W.-M. Yao et al.). 2006.
Cited 3902 times

4) Review of particle physics. Particle Data Group.
By Particle Data Group (Kaoru Hagiwara et al.). 2002.
Cited 3821 times

5) Wilkinson Microwave Anisotropy Probe (WMAP) three year results: implications for cosmology.
By WMAP Collaboration (D.N. Spergel et al.). Mar 2006. 89pp.
http://arxiv.org/abs/astro-ph/0603449
Cited 3561 times

There must be multiple reasons for this. What do you think they are? New instruments? The fact that cosmology has put both dark energy and dark matter on the table? The sudden increase in the amount of precision data in cosmology? Can you think of other reasons? Access to higher energies than can be produced in artificial accelerators like the LHC?

In a certain sense Cosmology now dominates physics. It has become a major driving force for uncovering new physics, comparable to the accelerator boom of the 1960-1990 period. The publication and citation rates merely serve to reflect this. What are the main reasons you think this has happened?

I am interested to learn what other people think about this. I have in mind another reason which I haven't mentioned and which I think has been basic to this--so I am curious to see if someone else mentions it.

 

[yogi]

Cosmology is built upon and incorporates most of the other sciences. It is deeply connected to the philosophy of our own existence - in particular the discoveries that led to global expansion have opened countless musings and argument about our beginning and our destiny
To quote Eddington "The conception of the expanding universe seems to crown the edifice of physical science like a lofty pinnacle...A few years ago i became strongly convinced that in these astronomical discoveries in the remoteness of space, we had picked up the key to the mysteries of the proton and electron..." The new interpretations of the accelerating scale have further fueled the search to find some deep meaning to our own place in the picture - and with each new discovery there is a new synergism to the implications ...thats my take ...thanks for posing the question

 

[marcus]

That's an interesting point of view. It wasn't what I had in mind myself or expected from others, and so puts a different light on it. Your response was a pleasant surprise.

 

[Wallace]

Many Scientists who work in the fields of say Chemistry or Biology are very practical people, committed to improving some aspect of our society by advancing our knowledge in some practical way. But I think many Physicists are cut from a different cloth, the quest there is about the ultimate fundamental questions. Sure there are many many practical benefits to Physics, but the personal drive is somewhat different, more a naked search for knowledge for the sake of it.

I think therefore that cosmology was a quiter field in the past because the lack of concrete detailed data meant that is was difficult to say anything very definative, heck it took decades just to get a reasonable agreement over the Hubble constant, and in the end that number doesn't tell you all that much in isolation (although is says a lot given other measurement we can now do).

Since the explosion of data coming from WMAP and huge galaxy surveys like 2DFGRS and SDSS the situation has changed, and what this has meant is that there are hordes of physicist coming into cosmology from other areas such as particle and nuclear physics. Folks that got into those areas in the hey days of accelerator and reactor physics are now seeing their fields as a bit of a dead-end; apart from the LHC there are not a lot of huge things on the horizon to be discovered and most of the work is polishing off loose ends. On the other hand, modern cosmology is a dynamic field with large paradigm changing discoveries looming. This attracts Physicists like bees to nectar, since it strikes at the heart of why most of them became picked up that career in the first place. Even things like string theory are far more likely to end up being testable through cosmology rather than in a lab, so cosmo is where the excitement is at the moment.

 

[George Jones]

From the preface to Weinberg's new (2008), authoritative book, Cosmology:

"The new excitement in cosmology came as if on cue for elementary particle physicists. By the 1980s the Standard Model of elementary particles and fields had become well established. Although significant theoretical and experimental work continued, there was now little contact between experiment and new theoretical ideas, and without this contact, particle physics lost much of its liveliness. Cosmology now offered the excitement that particle physicists had experienced in the 1960s and 1970s."

 

[Chronos]

'Hey, the universe has way better particle accelerators than we can build on earth.' At least that's what my ex's cousin, the livermore labs particle physicist, said circa 1980. Particle physicis is a well established clique in the cosmology club these days. Indeed, better instruments and funding are drawing a huge amount of interest in cosmology from all fields of science, as Wallace noted. Astrobiology used to be the poster child for crackpot science fiction, but looks quite respectable nowadays.

 

[BigFairy]

Thanks for the updates :)

 

[turbo]

Much of the "draw" of cosmology is a search for origins. It is tempting to think that we have the answers at our finger-tips, though I think hubris will humble us over and over again. There are objects at the very limits of our ability to detect them (quasars) that are highly metalized (generally Solar or super-Solar metalicities) and that show no evolution in absolute or relative metalicities with redshift, which is quite contrary to expectations under the paradigm under which early bodies were supposed to be poor in metals and in which larger bodies form by accreting from smaller bodies. We will progress, but breathless pronouncements of "precision cosmology" should be taken with a grain (^100) of salt.

 

[Chronos]

Indeed! We are all drawn to cosmology because it is so dang fascinating and weird. I'm mainstream inclined, but, relish opportunities to sieve through alternatives. That is what science is all about. We, in our fumbling ways, are posing the questions necessary to solve the puzzles, IMO.

 

[Naty1]

I can't find the exact explanation of one popular physicst/author I read over the last year or two which seemed insightful, but basically he said that cosmology and particle physics, physics of the large and small, and come to be seen as closely related, and with the availability of actual hard cosmological data, especially from satellite observations, the appeal of cosmology evolved to "real science" with actual data. Prior to the availability of actual data, it was difficult to confirm or deny competing theories since the universe is not especially amenable to man made experiments.

 

[f95toli]

Although a more mundane (partial) explanation for many of the citations is also that there are many researchers that work in field where the applications of the research is in cosmology.
An good example would be people who work on new astronomical detectors for astronomy; even if the paper is about e.g. electrical noise in a superconducting detector due to defects in the silicon substrate (which as it happens is a "hot" topic right now) there might still be a reference to WMAP in the introduction of the paper.

I don't think I've ever directly cited a cosmology paper; but I did use a picture from WMAP in a talk recently since radio astronomy is one of several possible application for a project I am currently working on; a reference to cosmology/astronomy can be quite useful if you trying to "sell" your research to a wider audience since it is something most people are interested in.

 

[oldman]

There must be multiple reasons for this...

Yes indeed. But most of the replies to your questions politely talk of carrots. What about sticks such as Not Even Wrong and The Trouble With Physics? Physicists are only human after all.

 

[Wallace]

I very much doubt the books you mention have had any impact upon scientist within the various fields concerned. They are certainly interesting and important books in terms of pop sci, but they haven't had any impact within the research community. Some of the problems those books mention may have, but not the books themselves.

 

[oldman]

I very much doubt the books you mention have had any impact upon scientist within the various fields concerned. They are certainly interesting and important books in terms of pop sci, but they haven't had any impact within the research community. Some of the problems those books mention may have, but not the books themselves.

You are much closer to the research community than I am now, Wallace, but are you so well acquainted with it that you can state flatly that such opinions "haven't had any impact on the research community"? I surmise rather that prospective physics researchers casting around for a field with reasonable future career prospects might well be influenced by Woit's book, in particular. I also wouldn't dismiss Not Even Wrong as pop sci -- some of it is quite sophisticated, even if he avoids mathematics.

I agree with all you say in your earlier post, where you set out the attractions of cosmology for physics folk very clearly. Lots of new data spiced with fundamental mysteries and you've got honey, let alone carrots! But don't underestimate the underlying hard-headedness of folk, either --- look how many physicists landed up as Quants on Wall Street and in The City, more's the pity.

 

[Fra]

There must be multiple reasons for this. What do you think they are? New instruments? The fact that cosmology has put both dark energy and dark matter on the table? The sudden increase in the amount of precision data in cosmology? Can you think of other reasons? Access to higher energies than can be produced in artificial accelerators like the LHC?

One reason I can imagine, that relates to Smolins views is that in the general quest for understanding the deepest nature of nature (ie including particle physics, unifications, cosmology etc), cosmology distinguishes itself from particle physics models in that the context of cosmological theories (scientists on earth) is a true subsystem of the system of study (the universe at large). This is in stronger constrast to particle physics where you a huge laboratory and massive accelerators provide the "context" of probing deep into the subatomic world.

As Smolin argued, a lot of the "old logic" in physics can be justified as long as the basis of theory is more stable than the systme of study. Ie. when we are studying small subsystems, and where we can attach our theory in an external relatively unaffected context.

This logic doesn't work in cosmology, which forces us to think a bit differently about science. I find this to be a good motivation for looking at cosmology-type theories, even from a theoretical and philosophical point of view.

When the context of theory and law, are deeply dynamically related to the system of study the conceptual scheme of modelling subsystems, and most forms of probabilistic and statistical arguments fails. Maybe there is an increasing awareness that it won't work to apply the old logic to cosmological theories because there is not thing as repetability or statistics when it come to stuff like the evolution of universes at different initial conditions.

The quest for new logic, makes cosmology interesting as it more obviously than particle physics, makes it clear that the same abstractions doesn't make sense from a scientific point of view. I think the issues exist also in particle physics but there it's more subtle, the context of a particle experiment is fairly clear. However the inference of the action of these indirectly observed systems instead start to get ambigous, which is the other side of the coin of the old logic. We need the "inside logic". But I think it's easier for everyone to see what this fails for comoslogy, than for subsystem physics.

/Fredrik