Exploring the Physics Community's Split: Theory vs. Experiment

[G01]

I've always wondered why the physics community was split the way it is. Why do we have people who are theorists and others who are experimentalists. It seems to me that every scientist should ideally be a mix of both. I've noticed that other science fields don't really have this split(at least not to the same extent). Is there a historical reason for it, or is it just by chance that physics ended up this way?

 

[ice109]

i was told that you need to focus to be good, someone doing both won't be as good as they would be focusing on one thing.

 

[G01]

But still, chemists and biologists get along well without this split. Maybe its the nature of physics, needing to have specialists in theory or experiment.

 

[ice109]

But still, chemists and biologists get along well without this split. Maybe its the nature of physics, needing to have specialists in theory or experiment.

well biology doesn't really have a theoretical aspect. and chemistry is applied particle physics so they have us as their basis. I'm probably wrong on all these accounts.

 

[G01]

I don't think biology doesn't have a theoretical basis, it is just somewhat less mathematical. They still model nature(theory) and then test those models with experiments.

 

[ZapperZ]

I've always wondered why the physics community was split the way it is. Why do we have people who are theorists and others who are experimentalists. It seems to me that every scientist should ideally be a mix of both. I've noticed that other science fields don't really have this split(at least not to the same extent). Is there a historical reason for it, or is it just by chance that physics ended up this way?

For one, some people are more inclined to do one thing versus the other. Many experimentalists, by nature, like to tinker with stuff and are more inclined to build things. Most theorists do not have that inclination. But this is really a very poor generalization.

The best theorists are those who do dabble in experiments and do tinker with stuff. Read Bob Laughlin's description of his childhood. Naturally, when he did become a theorist, his main attention are on experimental results, and he has the knack to figure out which experiments are more "robust" and "trustworthy" than others. If you are a theorist and you have no clue on which experiments to trust, then you might put your eggs in the wrong basket.

Correspondingly, the best experimentalists are those who also have a good grasp of the theory. This is especially true in high energy physics where you not only have to be able to come up with some of the most complex experiments and be able to reasonably predict some range of outcomes, but you must also be able to decipher the results (often with the help of theorists). As Rutherford likes to point out, it is why we are not just "stamp-collecting". Our knowledge of theory makes us not stamp collectors.

There is still this dichotomy because, frankly, not everyone can do everything. It takes a lot of effort to fully understand the theory in a particular area, and it takes a lot of effort to be an experimentalist that require a lot of time to build, design, supervise a project. So besides the natural inclination to do one thing versus the other, there is that limitation of effort and time. So we become one or the other. But that certainly doesn't mean that one can't straddle both sides. It has been done now and then. Bardeen, for example, was instrumental in helping the design of the transistor. Yet, he was technically a theorist, as evident by the BCS theory of superconductivity. So he won the Nobel Prize in physics twice, and they're both for the invention of a device and the theory of superconductivity. Is there any wonder why I admire his accomplishment very much?

Zz.

 

[ice109]

I don't think biology doesn't have a theoretical basis, it is just somewhat less mathematical. They still model nature(theory) and then test those models with experiments.

yea i can't put my finger on it but there's definitely something inherently different

 

[G01]

For one, some people are more inclined to do one thing versus the other. Many experimentalists, by nature, like to tinker with stuff and are more inclined to build things. Most theorists do not have that inclination. But this is really a very poor generalization.

The best theorists are those who do dabble in experiments and do tinker with stuff. Read Bob Laughlin's description of his childhood. Naturally, when he did become a theorist, his main attention are on experimental results, and he has the knack to figure out which experiments are more "robust" and "trustworthy" than others. If you are a theorist and you have no clue on which experiments to trust, then you might put your eggs in the wrong basket.

Correspondingly, the best experimentalists are those who also have a good grasp of the theory. This is especially true in high energy physics where you not only have to be able to come up with some of the most complex experiments and be able to reasonably predict some range of outcomes, but you must also be able to decipher the results (often with the help of theorists). As Rutherford likes to point out, it is why we are not just "stamp-collecting". Our knowledge of theory makes us not stamp collectors.

There is still this dichotomy because, frankly, not everyone can do everything. It takes a lot of effort to fully understand the theory in a particular area, and it takes a lot of effort to be an experimentalist that require a lot of time to build, design, supervise a project. So besides the natural inclination to do one thing versus the other, there is that limitation of effort and time. So we become one or the other. But that certainly doesn't mean that one can't straddle both sides. It has been done now and then. Bardeen, for example, was instrumental in helping the design of the transistor. Yet, he was technically a theorist, as evident by the BCS theory of superconductivity. So he won the Nobel Prize in physics twice, and they're both for the invention of a device and the theory of superconductivity. Is there any wonder why I admire his accomplishment very much?

Zz.

I remember reading in "Surely your Joking" that Feynman also liked to tinker with things and he was obviously a theorist. Wasn't Enrico Fermi also one of those guys that straddled the fence between theory and experiment?

 

[ZapperZ]

I remember reading in "Surely your Joking" that Feynman also liked to tinker with things and he was obviously a theorist. Wasn't Enrico Fermi also one of those guys that straddled the fence between theory and experiment?

Oh, definitely. That certainly is a very good additional example. In fact, his tinkering ability came to the forefront during the Challenger disaster hearing. Just a simple demo about what happened to the o-ring seal in cold water was as clear as anything anyone could have done.

Fermi was just brilliant at everything he did.

It is why I have always believed that the best theorists are the ones that do know a lot about experiments.

Zz.

 

[G01]

It is why I have always believed that the best theorists are the ones that do know a lot about experiments.

Zz.

I definitely agree. I think there are two many physics people out there that say stuff like, "I want to be a theorist all I need is a pencil and paper." I don't think this is the best attitude to have. I think people who say this or similar things seem to forget the purpose of science.

 

[ZapperZ]

I definitely agree. I think there are two many physics people out there that say stuff like, "I want to be a theorist all I need is a pencil and paper." I don't think this is the best attitude to have. I think people who say this or similar things seem to forget the purpose of science.

.. and although I have made jokes about theorists, and I've often questioned students who are deadset into becoming a theorists, I have never lost any appreciation for the importance of it.

Again, it is why we experimentalist are not just stamp collectors, because of our understanding of theories. So the best experimentalists must also keep a keen eye on theory. Besides, how else would you know what to falsify?



Zz.

 

[G01]

.. and although I have made jokes about theorists, and I've often questioned students who are deadset into becoming a theorists, I have never lost any appreciation for the importance of it.

Again, it is why we experimentalist are not just stamp collectors, because of our understanding of theories. So the best experimentalists must also keep a keen eye on theory. Besides, how else would you know what to falsify?



Zz.

Right now, my REU has given me a newfound appreciation for the work that goes into an experimental project. I've had to do lab work and read papers on theory, so I have first hand experience on needed to know both.(That and I've learned that I need steadier hands!) It seems to me, a lot of people think there is less glory in experiment, but I don't think this is true. So far, in my experience, the experimentalist REU'ers seem to work the hardest! All I know is that my roommate has a theoretical cosmology project and he's asleep when I leave for the lab, and already back playing video games when I'm getting back from the lab.

 

[ZapperZ]

Right now, my REU has given me a newfound appreciation for the work that goes into an experimental project.(That and I've learned that I need steadier hands!) It seems to me, a lot of people think there is less glory in experiment, but I don't think this is true. So far, in my experience the experimentalist REU'ers seem to work the hardest! All I know is that my roommate has a theoretical cosmology project and he's asleep when I leave for the lab, and already back playing video games when I'm getting back from the lab.

I just want to say how envious I am at you and other members on here who already have REU's and other research experience while still being undergraduates. I learned very late in my undergraduate years on the value of such a thing. I only spent 2 months in a short internship at Fermilab a year before I graduated, and I wish I had done a lot more (this was the impetus for writing my essay, so that students can learn from what I should have done and should have known).

You guys have such a huge mountain of opportunities in front of you and some of the most exciting times in your professional careers.

<sniff>

Zz.

 

[G01]

I just want to say how envious I am at you and other members on here who already have REU's and other research experience while still being undergraduates. I learned very late in my undergraduate years on the value of such a thing. I only spent 2 months in a short internship at Fermilab a year before I graduated, and I wish I had done a lot more (this was the impetus for writing my essay, so that students can learn from what I should have done and should have known).

You guys have such a huge mountain of opportunities in front of you and some of the most exciting times in your professional careers.

<sniff>

Zz.

I actually learned about REU's from a friend of mine who was a couple years older and also a physics major, but the whole of PF in general has been an invaluable resource during the application process as I'm sure it has been for many others.

 

[ice109]

Man you guys are killing me, now I don't know what to do theory or experiment? Honestly my natural inclination is to do both! I like to know things rigorously but I also like to tinker.

 

[ZapperZ]

Man you guys are killing me, now I don't know what to do theory or experiment? Honestly my natural inclination is to do both! I like to know things rigorously but I also like to tinker.

Oh, you poor fella. Maybe it would be inappropriate for me to show you this article then, written by a theorist too!

http://www.physicstoday.org/vol-53/iss-7/p15.html



Zz.

 

[Dr Transport]

As Zapper has said, the best physicist is one who has a grounding in both theory and experiment. One other thing needs to be said, although a theorist by training, Landau it has been said, would throw another theorist out of his office to answer a question or do a calculation for an experimentalist because he believed that their problems were more important. Landau would also spend the beginning of his day going from lab to lab helping and discussing the experiments being performed to help them stay on track. Bardeen made Bob Schrieffer spend a year in the lab as a graduate student to become a better physicist. Many universities make all graduate students take lab courses during their career so that they are better trained.

In discussions with my advisor, he has said that I have become a better physicst because I have spent the better part of the last 3 years in the lab and my theoretical background has made a big difference.

If an experimentalist isn'comfortable with theory then how does he feel comfortable with what he has done and the interpretation. On the other hand a theorist needs to know how to measure things because he can better interpret the data as it comes to him.

 

[ice109]

Oh, you poor fella. Maybe it would be inappropriate for me to show you this article then, written by a theorist too!

http://www.physicstoday.org/vol-53/iss-7/p15.html



Zz.

that's all well and good but the revolution of the early 20th century would never have occurred for all those eastern european theorists. supporting already established theory maybe but do theorists make leaps into completely novel territory?

 

[G01]

that's all well and good but the revolution of the early 20th century would never have occurred for all those eastern european theorists. supporting already established theory maybe but do theorists make leaps into completely novel territory?

Do you mean relativity and quantum theory? Those theories wouldn't have even been considered if there wasn't experimental evidence suggesting there were big problems with the current models? So yes, even then it was a give and take situation between theory and experiment.

I am by no means anti-theory. I just think theory should go together with experiment(Ideally, of course. I know it's hard when people have to specialize.). That's why I think I like the fields of solid-state and condensed matter physics. It seems that in those areas theory/experiment/application are more closely intertwined. This is only my opinion, I don't know what people who are actually experts in the fields think. I would like to know is my current view is correct though! Anyone in those fields please tell me what you think!

 

[G01]

Oh, you poor fella. Maybe it would be inappropriate for me to show you this article then, written by a theorist too!

http://www.physicstoday.org/vol-53/iss-7/p15.html



Zz.

Nice article. I like how it points out how the Theory-Experiment split may in fact be holding back progress. It makes you think...

 

[ice109]

i don't think experimentalists create things. I'm probably dead wrong. and i don't mean experimental setups to test theory either. i mean if the standard model is completely wrong i don't think the experimentalists are going to be the ones positing something completely novel.

 

[G01]

i don't think experimentalists create things. I'm probably dead wrong. and i don't mean experimental setups to test theory either. i mean if the standard model is completely wrong i don't think the experimentalists are going to be the ones positing something completely novel.

Why couldn't a good experimentalist come up with something novel? Also, consider this: How would we know that the standard model was wrong(hypothetically of course) if not for the experimentalists? Your not giving experiment enough credit in my opinion. Once you start not caring about experiment you stop caring if theories actually describe reality. One follows the other as far as I can tell. And if this happens, you are no longer a scientist. Theories begin and end with experiments.

 

[ice109]

Why couldn't a good experimentalist come up with something novel? Also, consider this: How would we know that the standard model was wrong(hypothetically of course) if not for the experimentalists? Your not giving experiment enough credit in my opinion. Once you start not caring about experiment you stop caring if theories actually describe reality. One follows the other as far as I can tell. And if this happens, you are no longer a scientist. Theories begin and end with experiments.

the point is not whether someone can or can't, the point is it usually does not happen. I'm very well aware that experiment is the nature of science, and I'm even aware that einstein chided people for quantum theory because of its indeterminancy. I'm just saying you need someone to posit completely radical things and i personally do not know of any experimentalist that has done that.

 

[G01]

the point is not whether someone can or can't, the point is it usually does not happen. I'm very well aware that experiment is the nature of science, and I'm even aware that einstein chided people for quantum theory because of its indeterminancy. I'm just saying you need someone to posit completely radical things and i personally do not know of any experimentalist that has done that.

I don't know what this has to do with quantum uncertainty but what I'm trying to say is that the experiments give the reasons to come up with new, radical theories. What would be the point of proposing new radical theories, if the experiments continued to show that the old ones worked fine!

You need both. Can we agree on this? You need people to model reality and you need people to explore nature to give the basis for and tests of the theories.

 

[ice109]

I don't know what this has to do with quantum uncertainty but what I'm trying to say is that the experiments give the reasons to come up with new, radical theories. What would be the point of proposing new radical theories, if the experiments continued to show that the old ones worked fine!

You need both. Can we agree on this? You need people to model reality and you need people to explore nature to give the basis for and tests of the theories.

completely agreed.

the relevance to quantum uncertainty was that even the "great" theorist himself still abided by reality.

 

[G01]

completely agreed.

the relevance to quantum uncertainty was that even the "great" theorist himself still abided by reality.

Cool!