survey with physicists

[gusl]

Physicists,

Kuhn would say that most of the theorizing you do, whether explaining new phenomena, predicting the result of novel experiments, etc involves reusing tricks from the examples you learned as a student (i.e. exemplars, "puzzle solutions").

Kitcher interprets Kuhn in an unusual way, and has said that ``Science advances our understanding of nature by showing us how to derive descriptions of many phenomena, using the same patterns of derivation again and again.''

To what extent are the above statements true, and what is a good example? In the course of doing physics, in what ways do you reuse examples from your experience? Are you just taking shortcuts by reusing previously-derived results (i.e. taking them for granted), or is there something else going on?

Comments

[spoonless.livejournal.com]

There is definitely a lot of re-using of results, and I think it's because nature is so self-similar. It's amazing how often we run into one problem that is analogous to another we're more familiar with. Occasionally, but rarely, we encounter a problem that's entirely new and that requires new mathematical techniques to deal with (string theory is a good example of that... and one of the reasons the progress on it is going so slowly.)

I think one of the best examples of re-using stuff in physics is the harmonic osscilator (springs, waves, vibrations, etc.). It shows up in every branch of physics again and again. The reason it shows up practically everywhere is because it happens naturally any time when you have a system with negative feedback. Although again, my view is that it's nature that re-uses stuff a lot... if we didn't do the same, then we wouldn't be modelling it correctly.

[spinemasher.livejournal.com]

"Re-use" is not the term I would use. For example the advent of the automobile, though no self-propelling personal land transport vehicle had been invented prior to the car, all the pieces were! The wheel was invented far before our recorded history, the internal combustion engine was invented almost half a century prior. Yet the car is completely unique and we call it an innovation. If Kuhn is content calling everything "re-used" then that's fine for him, though I challenge him to invent something.

In my personal research I use pieces of knowledge, either metaphors from everyday life or well-known mathematical facts and incorporate these seemingly unrelated or extraneous pieces of knowledge into a relevant and real life physical system. Specifically in my case, I apply facts about functional analysis, topology and geometry to the concept of the Standard Model and the notion of probability amplitudes of fundamental point particle dynamics. In essence, I take mathematical facts that are about 50-100 years old and see how they fit in nature only in a non-obvious fashion. Usually it involves recognizing that some physical parameter, field, variable is either a function of more variables than we thought previously or that some simplistic model and/or constant is in fact more complex and/or non-constant.

There are tons of examples in the history of physics. Einstein found that the geometry of space-time in fact evolved with the energy content of the matter in/on the space-time. Yet he used both Riemann's mathematics of differential geometry and Riemann's conjecture that gravitation was fundamentally geometric. Had it been done before? No. The reason is that although Riemann invented the machinery (the wheels and the internal combustion engine) he never quite worked out how to piece them together in order to model nature. Now it is a well-known historical fact that Riemann lived a fairly short life. Is this meaningful? Would he have finally done Einstein's work 20 to 30 years earlier had he lived longer?

The answers to those questions however are totally irrelevant. The point of the matter remains that arranging, fitting together and tying together information in novel-useful ways is the definition of innovation. The fact that the pieces had pre-existed is neither here nor there. This is the difference between an historian and a scientific innovator. Kuhn needless to say is just an historian.

Incidentally, it is also a well-known historical fact that many people had been researching the idea of a "personal train". But ultimately this idea or meme if you will did not survive. The reason is that the meme is subject to its environmental constraints much like genes are. However the meme's environmental constraints are not necessarily purely physical or biological. In many cases memes die out because of social and economic constraints. It was impractical and too costly to lay track everywhere you wanted to go. One may object and say but roads are laid everywhere now. The short answer is no, roads were only laid after cars became prevalent enough. In fact, in many places in my country people still drive their cars on dirt roads around their local neighborhoods. I know for sure that this is also still true in many parts of England and France. A small farmhouse will not get an expensive road installed by the local government because the use of that road would not justify the economic expenditures.

But that's just it! The car was an ingenious invention because it "laid its own track" in a manner of speak by flattening out dirt and pebbles so as to be more and more drivable with use. This shows that practical implementation is also a key ingredient beyond just fitting together strange and different things.

But I don't know, the car may not be all that great, flattened dirt and pebbles existed far before cars, all the way back to the days of the animal drawn cart/chariot. Sarcasm aside, I believe Kuhn suffers from the affliction of the mind known as, "over reductionism".

I think that's just it!
A person who can think but cannot do says everything is easy.
A person who can do but cannot think says that everything is hard.
But a person who can both think and do knows that everything is just as it should be.