Disenchanted with Physics Other Sciences?

[twofish-quant]

I've often felt disenchanted with physics throughout my physics education. Physics courses often feel more "math"-y than "science"-y, and you don't even need to know anything about the scientific method in order to get the physics degree.

Part of it is that when people write about the "scientific method" they are observing what scientists do. It turns out that sometimes scientists do something different than what the textbooks say they do. One thing that is really interesting and a little scary is to look at how people describe science in different ways in different time periods.

The idea that "science works through falsification" was created in 1928. The notion of science as paradigms was an idea that started in the 1960's. One thing that's useful about having a Ph.D., is that I can make statements like "scientists really don't use the scientific method" and be taken someone seriously.

Sometimes, reading the modern physics from a historical perspective can re-ignite the scientific excitement that you had for physics.

Yes, on the other hand you then get into debates over how accurate the history is. Something that that happens after you've done physics for a few years is that you "live history." If you just study anything for five years, then you'll find out stuff that people didn't know five years ago.

 

[Gordianus]

But if there is a correspondence between the math and the physical world, you can figure out stuff about the physical world by looking at the math.

Also, things get interesting if you go "deep". For example, it's a fact that electromagnetism is a result of U(1) gauge invariance (google and get the wikipedia page). If you assert that space has a particular symmetry, then all of electromagnetism pops out.

However true this statament is, I don't think this "ultra-abstract" methods gets us (me) any closer to understanding physics.
When I was young, I was elated with Landau's mechanics book. Once you accepted a least action principle was at work, everything went out smoothly. Today, many years later, I think we first had Galileo, then Newton and Hamilton came at the end of a very long list of famous names. Similarly, I'd rather picture Coulomb rubbing glass, Oersted moving the wire close to the compass, Maxwell and, as a grand finale, we conclude everything is a consequence of a given simmetry. The last assertion is extremely powerful and abstract but, if I started with it, I certainly doubt I'd have any "feeling" about electromagnetics.
Math is a most powerful tool, but relying solely on it deprives us from "trudging" the path that let's us "grab" the idea (This is my humble point of view after teaching physics many years)

 

[darkchild]

Reading what he has to say may justify why concepts like magnetic fields are useful, or even necessary.

If that is directed at me, I've already stated that I already understand why magnetic fields are useful...as for being necessary, it depends on what one claims they are necessary for.

 

[darkchild]

And the basics are pretty useless in building the machines that get the people with power to spend money on this.

Useless to whom? I have specifically stated several times in this thread that I like to understand how things work. It is pointless for you to respond to me and tell me that knowledge that I find valuable is useless to some other people, or for some purpose that is not my own.

 

[darkchild]

Two comments:

You seem to be hung up on what is "real". You can look at many threads here where people get tangled up in the same question. That's a question of philosophy, so it's not surprising that physics doesn't address it. I maintain that the magnetic field is no more and no less real than "wind" (which, after all, is a velocity field). They are both invisible, they both interact with some things and not others, they both obey certain continuity equations, they both carry energy and momentum.

I have not used the right word; I do not mean to question whether physics concepts are "real" or not in a philosophical sense, I mean to question whether or not (and to what extent) they are based on observation.

"Wind" is just a name given to an observed phenomenon; it is magnetism, the phenomenon of the behavior of magnets, that is it's analogue. To me, they are both "real" in the sense that they are observed. Magnetic fields, on the other hand, have little to do with observation. As far as I can tell, there is nothing in the observation of magnetism that would necessarily suggest magnetic fields as the culprit. As I've said up-thread, it could just as well be invisible unicorns pushing and pulling magnets together as a magnetic field. It is not "real" in the sense that it is a totally arbitrary construction.

Additionally, you seem to be unhappy with the mathematical nature of physics.

You are mistaken; I enjoy math. In this thread, I have expressed dissatisfaction with the math I did as an undergraduate because of the models that I was manipulating with the math. I also expressed the idea that understanding the basic physical principles of how something works does not require math. Neither implies that I dislike math in general.

 

[darkchild]

What you actually want is philosophy of science rather than physics which is purely an empirical science.

The philosophy of science is not going to explain how magnets attract and repulse one another.

 

[darkchild]

You can explain everything without ever touching the concept of magnetic fields,

Can you explain to me how magnets attract and repulse one another, or how they attract or repulse live wires, without invoking the concept of a magnetic field? I would love to hear it.

Edit: One thing that would be good for this discussion though would be something that you would consider to be an adequate explanation, if you just say what you don't want this will never lead anywhere.

I don't see how it's possible for me to answer that question. How can anyone say what is an acceptable explanation of something they don't fully understand? How can anyone suggest an effective way to explain something when they don't know what will be explained?

The deal with magnetic fields is that it doesn't change anything to view the force between particles as if it were a field associated with said particles.

It depends on what you're talking about changing. Obviously, the use of the concept doesn't change whatever phenomenon is being described; however, the way I conceptualize things matters to me, so adopting one arbitrary concept versus another does change something for me.

Now from the expression of the force we can see that such a field would have certain qualities, etc. From that point on the rest is just about calculations that would be true even if we never invented the magnetic field but everything would be much harder to explain and do.

I understand all of that. I don't see what it has to do with the point I'm making. The point that keeps being made over and over again in the replies is that magnetic fields are useful...ok, I get it, I know this already. They are generally useful in physics. They are not useful for one particular purpose of mine, and that is not affected by how useful they are in physics.

 

[darkchild]

The deal with maths is that if that if the first equation is true then by necessity the second equation will also be true!

I didn't say anything about the resulting equation no longer being true. Just because it's mathematically true doesn't mean it has a particular physical interpretation, or any at all for that matter.

 

[darkchild]

That's reality, and that's physics. You might be annoyed because the model is incredibly complicated and includes lots of fudge factors and random items in it. But reality is messy. Get used to that.

You need to read more carefully. I don't appreciate your assumptions concerning what annoys me, not to mention what appears to be condescension, especially since you don't even seem to understand what I'm talking about.

Reality is what you observe.

I agree.

If you can give me that explanation, then I don't have a problem with explanations based on unicorns.

This thread isn't about you. It's about me.

 

[darkchild]

Why do you think that.

I think that way because all sorts of physics concepts can be explained without math.

Math is a language. Do you think that you could explain a physical theory without words or pictures? Words and pictures aren't explanations, but explanations are impossible without them.

Considering the fact that words are the primary means of communication among humans, especially for complex subjects, while we can live, communicate, etc. just fine with little or no math, there is really no comparison between the two. Most of the posters in this thread have done all sorts of explaining with no math whatsoever, but it would have been impossible without words. Whether or not an explanation is impossible without math depends upon the nature of the explanation.

And I don't really think it's possible to easily explain magnets without math. I know that this explanation is a good one because it says that when I put object X next to object Y, I get 2.1 Newtons of force and that's more or less what I measure when I actually put object X next to object Y. Without the language of math, how am I supposed to say 2.1 Newtons of force?

It depends on what one wants to explain. If you are asking about amounts of things, as in your example, of course you need math. If one simply wants to know what happens when a magnet is in the vicinity of a live wire, it's not necessary.

Other sciences are even *worse* at trying to get what you think is reality than physics. Physics deals with simple things. You put two magnets next to each other, and the same thing happens. You put two people next to each other or two cells next to each other, and there are all sorts of complicated interactions that you can't control.

You have misunderstood. It's not complexity that I am complaining about.

 

[darkchild]

call me crazy but if you have these issues with why you don't like physics, and then every other aspect of science can be considered a branch of physics, then how is switching to anything else going to make a difference?

I think that whether or not "every other aspect of science can be considered a branch of physics" is debatable.

 

[Ryker]

It depends on what one wants to explain. If you are asking about amounts of things, as in your example, of course you need math. If one simply wants to know what happens when a magnet is in the vicinity of a live wire, it's not necessary.

Why? It seems to me you just decided that doesn't need to be backed up by maths, and are now just clinging to that belief without allowing evidence to the contrary. Words cannot express everything, so how can you just decide this is one thing they can? Both words and maths are human constructs, so why would you say one is superior to the other when they are just different? It seems to me you're trying to get across the ocean by car, but even though you see you can't, you still don't acknowledge the existence of planes and ships as real and valid means of doing just that.

And I'm not talking specifically about magnets and wires here, because I'm not far enough in my Physics education to comment on that specific case. But this is what I gathered from your approach to things.

 

[darkchild]

Why? It seems to me you just decided that doesn't need to be backed up by maths

Backing something up is not the same thing as giving a simple description of how something works. Ever hear of conceptual physics courses? How can they possibly teach anything if math is required to explain every little detail of physics?

Most of the things in this post that you have ascribed to me are things that I have neither stated nor implied (such as the idea that words are superior to math). You're making false assumptions about what I think, and I can't and won't answer about something I haven't said.

 

[Ryker]

Backing something up is not the same thing as giving a simple description of how something works. Ever hear of conceptual physics courses? How can they possibly teach anything if math is required to explain every little detail of physics?

I never said math is required for everything, I said it may be required for some things that cannot be fully explained by just words. You, on the other hand, are saying that everything should be explained by words and that is what I'm disputing. Also, I don't see why you'd bring up conceptual physics courses, because it seems that if you're disenchanted with how Physics is being taught, they obviously aren't doing what you think they should be (that is, explaining things conceptually without the need for math). And if you don't think words are superior to math in all aspects, why do you then not accept explanation with the use of the latter, but demand the use of the former?

 

[Feldoh]

The philosophy of science is not going to explain how magnets attract and repulse one another.

Neither will physics if you're looking for the end-all singular answer. All the physical sciences are grounded in observation.

How else would you describe the world? All you will even know in physics is due to observations and that is all you will ever know from it. If you want higher truths than observation then yes, you better look to some other sort of philosophical description of the world. That's all physics really is is the logic involved with observation.

EDIT: This guy's just arguing for the sake of arguing. People keep making the same points and this joker won't accept any of them. I'm calling troll.

 

[lurky]

Darkchild, I don't think there's anything wrong with you for questioning what you've learned. I really think that your issue is that you weren't told early enough that we don't know everything. So now you've gotten to the end of the book (your undergraduate) and you're feeling dissatisfied because the conclusion isn't as thorough as you had hoped. Does that suck? Well, yeah, of course it does. I think it would have helped had your instructors better prepared you for this earlier, but they didn't, so now you have to just learn to accept that we don't yet have all of the pieces of the puzzle and are still stuck with mental constructs. In fact, we will probably never know everything (how could we know if we did?), so mental constructs will probably always exist.

Mental constructs aren't so bad. The reason why you don't see unicorns being invoked in explanations is because those would be more complex than necessary.

 

[JDStupi]

Alright, your doomed to never know. Period. that's the first thing you have to understand. What does us existing in a socio-environmental milieu have to do with anything? It has to do with our limitations, and what your asking is for an explanation that is independant of the limitations of existing in such a manner. Again, your looking for a "View from nowhere", it is the Kantian insight that, neccesarily, anything that you intuit will be limited by the way in which you intuit it. When twofish speaks about mathematics as a language, he isn't saying its the only language, what he is saying however is that different forms of language are used for different modes of explanation, just as we wouldn't explain psychological motivations in terms of equations, it seems to be that, for whatever reason, our limitations make it such that in terms of explanation, however inadequate by your standards, mathematics is our only means of access to such physical phenomena. You also have to get the idea of strict deductive neccessity out of your head. No nothing "necesarrily" says that the mathematics used to describe "charged particles" requires the interpretation of "magnetic field" in the metalanguage we use to evaluate the truth claims of the theory, but what in your world is a necessary truth? Besides mathematical tautologies, what is "neccessary"? Our world, exists in possible explanations and combinations of deductive, inductive, and abductive inferencing and you cannot expect to hold all explanations to the standards of "neccessity".
This isn't an argument. Don't quote me an say "blahblahblahblah" and be so hard-headed, how about you consider what people are saying, I'm not arguing over whether your right or wrong. I'm simply suggesting that, for your own good, you rigorously analyze what you mean by "explanation" "neccessity" "language" "truth" "physical" "reality" and relateds notions. Don't argue with me, argue with yourself. When you shift around the words and say "Something that doesn't pass figments of the imagination off as physical phenomena" ask yourself "What constitutes a "figment of imagination"?" "What is a physical phenomena?" "How would I come to know a physical phenomena?" "What would constitute an explanation of a physical phenomena?" "How is anything explained? What does "explain" mean?". Its quite odd that you ask such questions and are disenchanted with the state of things, but then limit yourself by refusing to try to get to the bottom of the matter and refine your notions.

 

[Klockan3]

Can you explain to me how magnets attract and repulse one another, or how they attract or repulse live wires, without invoking the concept of a magnetic field? I would love to hear it.

We know how electrons and protons behave near each other, how they accelerate etc. This is deduced by observing the acceleration between the particles which is found to depend on the distance and their relative velocity. Magnets are objects which have a macroscopic amount of electrons moving in a uniform way, so even though the effects of the protons/electrons eliminates each other on average if you don't consider movement we will still see that these objects will effect each other. Now from our observation on how moving electrons accelerate each other we can also deduce that the electrons in one magnet will accelerate the electrons in the other magnet and vice versa. In which direction depends on the relative electron currents, if they are aligned they attract otherwise they repel each other.

There, no mention of any abstract concepts at all, just some particles and some observations on how particles behaves. This isn't hard at all, it seems to me that your problem is that you don't understand what people mean with for example magnetic fields.

 

[twofish-quant]

As I've said up-thread, it could just as well be invisible unicorns pushing and pulling magnets together as a magnetic field. It is not "real" in the sense that it is a totally arbitrary construction.

I don't understand how magnetic fields are less "real" than "wind." If you put together a loop of wire and start running and you find that there is a current in the loop of wire, then something is there, isn't it?

It's not arbitrary since you need to come up with numbers that let you calculate how much current there is in a wire.

I also expressed the idea that understanding the basic physical principles of how something works does not require math.

And I think that's impossible. As far as conceptual physics courses, one thing that people taking conceptual physics courses need to be told is that they aren't learning physics. They are getting a taste of what physics is like, but they aren't learning physics, because physics requires numbers and math.

 

[twofish-quant]

I think that way because all sorts of physics concepts can be explained without math.

Not very well. The problem with trouble to explain a concept without math is that in physics, you know something is true because you get 2.1 on the meter, and without math, there's nothing to compare with the number on the meter. Because the observations are mathematical, I just don't see how you can provide a satisfactory explanation without math.

Considering the fact that words are the primary means of communication among humans, especially for complex subjects, while we can live, communicate, etc. just fine with little or no math, there is really no comparison between the two.

There are some areas of human existence where math is unnecessary, but there are areas in which math is essential. Try going to a grocery store and buying bread without math. It can't be done. The person with the bread is going to require that you have $X in cash for Y loaves of bread. "Conceptual understanding" isn't going to help you very much when you try to figure out how much money is in your bank account.

It depends on what one wants to explain. If you are asking about amounts of things, as in your example, of course you need math. If one simply wants to know what happens when a magnet is in the vicinity of a live wire, it's not necessary.

Yes it is, because I want to know if there is 2.1 amps of current going through the wire or 5 amps of current.

 

[twofish-quant]

Backing something up is not the same thing as giving a simple description of how something works. Ever hear of conceptual physics courses?

Yes. I have.

How can they possibly teach anything if math is required to explain every little detail of physics?

They don't teach very much. I don't think that conceptual physics classes teach very much (if any) physics at all.

 

[Shackleford]

Neither will physics if you're looking for the end-all singular answer. All the physical sciences are grounded in observation.

How else would you describe the world? All you will even know in physics is due to observations and that is all you will ever know from it. If you want higher truths than observation then yes, you better look to some other sort of philosophical description of the world. That's all physics really is is the logic involved with observation.

EDIT: This guy's just arguing for the sake of arguing. People keep making the same points and this joker won't accept any of them. I'm calling troll.

Maybe he's Michael Faraday.

 

[Sankaku]

This thread is very interesting to me. I cannot speak for anyone else, but I think the issue with mathematical models in science is that they often describe relationships that have very little analogue in daily life. That makes it hard to replace them with anything else that is familiar. Your example of unicorns doesn't address the point that the math is revealing something about the underlying structure of what is going on. It doesn't do a good job with 'what' (unicorns vs fields) but it does ok with revealing the relationships/processes that are happening.

One view is that math is just the language we are forced to use to discuss areas where our regular language is inadequate. Once you really look at anything in any depth, what we think we actually know dissolves into something much less tangible. Using a mathematical construct seems to be the best we can do when dealing at scales the human mind did not evolve to understand directly.

Is there a better way? Maybe; I hope you find it and can come back and tell us all...

 

[Odysseus]

Darkchild, I thought you would be interested in the fact that classical electrodynamics has been formulated completely in terms of a variational principle that does not invoke any fields. More information http://nobelprize.org/nobel_prizes/physics/laureates/1965/feynman-lecture.html" . Scroll down until you see the only bit of mathematics on the page (it is a popular lecture) the paragraphs surrounding are relevant.

 

[twofish-quant]

Darkchild, I thought you would be interested in the fact that classical electrodynamics has been formulated completely in terms of a variational principle that does not invoke any fields.

Invoke any fields explicitly.

The variational principle implicitly creates a field :-) :-) :-) Six of one, half dozen of the other.

 

[twofish-quant]

Also if you find out that there are five or six equivalent ways of describing something, there is usually some extremely deep and abstract mathematical reason why.

One theorem is that every symmetry results in a field, so what particle physicists have been looking for for the last several decades is to start with some "obvious" symmetry and then show that they create fields which explain everything.

 

[mal4mac]

Background information: I received my B.S. in Physics with an Astrophysics concentration last month. I was confused and unhappy with what I was learning during my university studies. I've come to realize that I pursued Physics with the expectation of learning how the world worked; what I actually learned about (beyond first year physics or so) were a bunch of metaphors for how the world works (models) and how to do all sorts of calculations with these metaphors. Sometimes, I sit and marvel at all the work I did, all the physics that is being done all over the world, and has been done all throughout time, juxtaposed with the fact that scientists still don't know the answer to "how" with regard to fundamental questions.

... I began to wonder if Earth Science or Planetary Science are more objective-reality-focused than Physics, and if I would find some satisfaction in studying them in graduate school. I know that some of the material will refer to the aspects of Physics that I dislike, but I could be fine with that as long as it is not the case most of the time. I would like some insight about these fields, given the information I've mentioned about my interests and perspective. I'm somewhat inhibited in my ability to research it myself right now, being in a foreign country where I can't read the language well enough to make good use of a library, but I can look up research papers, etc., online if anyone has that sort of suggestion.

This was not easy for me to express, so thanks for taking the time to read it and for any suggestions.

I ended up in the same position as you three decades ago. That led to a variety of jobs in various sciences. You don't get any nearer to "real reality" doing "Planetary science" or whatever. It doesn't really matter which science you take, if you like the actual process of thinking logically/mathematically/programatically then stay in science, just choose whatever job pays best/has the nicest colleagues/isn't too crazy a work environment/short hours. Look for enchantment in Mozart and Dickens and girlfriends. Reading some pop philosophy might help orient you (Bryan Magee, Alain de Botton, ... keep away from Kant and Aristotle though... to much pain...)

 

[drkatzin]

Actually, the magnetic field is very real. The "action at a distance" way of looking at electromagnetic phenomena has been shown to be false: if you have two charge distributions in vacuum, and you change one of them (move charges around), the resulting "information" (i.e. the forces on the other charge distribution) does not immediately reach the other charge distribution. There is a finite transfer time of signals, equal to the speed of light.

So what entity transfers information between the charge distributions? There's no material substance traveling between them, since we're dealing w/ vacuum. The electric and magnetic fields are the information carriers of electromagnetic phenomena: they store energy and transfer momentum.

 

[vtakhist]

1) The most reasonable position seems to be to accept that you are a limited human being...as we all are...and thus we cannot find out some things...ever...such as empirically prove/disprove God...etc.

2) So far...Scientific Method IS THE BEST method of getting consistent results from empirical data...and physics being the most fundamental and rigorous science is the best possible way we have as of now to explain how everything works (be it in terms of models and approximations)

3) Physics more or less accepts on faith (as other sciences) that empirical data can yield knowledge...

BUT all other sciences go even further...they not only accept that on faith...they also accept on faith physics etc...and the more applied you go the more you accept on faith...

4) given your problems, you either can leave physics and go into philosophy (where you can question almost everything including empiricism etc.) etc. or stay here in physics (where you don't question empiricism but get more "real" results)...or maybe go into math. (but it has its own worries)...all other fields will yield to even further disappointment since the further you go from these 3 the more you have to accept on faith

 

[Shackleford]

Also if you find out that there are five or six equivalent ways of describing something, there is usually some extremely deep and abstract mathematical reason why.

I always think this is the coolest thing, explaining something mathematically several different ways.

1) The most reasonable position seems to be to accept that you are a limited human being...as we all are...and thus we cannot find out some things...ever...such as empirically prove/disprove God...etc.

2) So far...Scientific Method IS THE BEST method of getting consistent results from empirical data...and physics being the most fundamental and rigorous science is the best possible way we have as of now to explain how everything works (be it in terms of models and approximations)

3) Physics more or less accepts on faith (as other sciences) that empirical data can yield knowledge...

BUT all other sciences go even further...they not only accept that on faith...they also accept on faith physics etc...and the more applied you go the more you accept on faith...

4) given your problems, you either can leave physics and go into philosophy (where you can question almost everything including empiricism etc.) etc. or stay here in physics (where you don't question empiricism but get more "real" results)...or maybe go into math. (but it has its own worries)...all other fields will yield to even further disappointment since the further you go from these 3 the more you have to accept on faith

Excellent post, IMO.

 

[Daverz]

Background information: I received my B.S. in Physics [...] scientists still don't know the answer to "how" with regard to fundamental questions such as the operation of magnets.

I think we're being played:

http://knowyourmeme.com/memes/fcking-magnets-how-do-they-work

 

[ZapperZ]

It is safe to say that this thread has meandered way beyond "Academic Guidance".

It is done.

Zz.