Friday, August 27, 2004

So You Want To Be A Physicist - Part 4

So far, I have covered what I believe a student needs all the way to the end of the 2nd year of studies. In most schools in the US, an undergraduate must have a declared major by the end of the 2nd year (if not sooner). So by now, you should already be officially a physics major. Hopefully, you would have made acquaintences with other physics majors and know who are in the same year group as you. This is important because chances are, you may want to find someone to discuss homework problems, etc. This is where having a local chapter of the Society of Physics Students (SPS) at your school can be useful. You get to meet other physics majors, and also talk to the more senior students who can give you a better idea of what to expect (or which professor to avoid in certain classes). You should also keep in mind that there is a good chance that these are probably the same people who might continue on in this profession, and that the friendship you are establishing might someday turn into a valuable point of contact in your professional career. Never underestimate the value of personal contacts.

The transition from the 2nd year into the 3rd year of college can mean smaller classes and more advanced subjects. This is where you start studying the "meat" of a physics program - what I would call the 3 foundations of physics: classical mechanics, electromagnetic fields, and quantum mechanics. These are taught in separate courses, typically over 2 semesters each. Typical textbooks for each course are: classical mechanics - Marion or Symon; E&M: Griffith, Reitz/Milford/Christy; QM: Griffith, Liboff. Now pay attention to this: ALL other physics subjects BUILD on the foundation laid by these three courses. The importance of these subjects cannot be overemphasized. In fact, if you are able to do it, you may even want to consider lowering your class load for 1 or 2 semesters while you're taking one or more of these classes just so you can devote extra time to them. An E&M class, for example, can easily suck in a lot of time to understand and the homework problem can take a long time to finish. If you can afford it, do not hesitate to buy one of those books that have sample questions and worked out answers (Schaum and Rhea have a series of those). Now don't cheat! Use them as guides and extra practice exercizes to make sure you understand the material.

If you are in a school with a small student population, chances are that the faculty would already know you either by sight or by name. If not, this is where you have to start distinguishing yourself. Talk to your instructors if you do not understand something, that is why they have office hours. Introduce yourself so that they know your name. By the middle of your 3rd year, you should have enough physics knowledge that you might be somewhat useful to do some work. Ask around if there are any research projects or groups that you can work in, or find a professor that might be interested in giving you a simple project for you to work on. This is especially relevant in your 4th and final year where most schools have a senior research class available. Start attending your department's weekly seminar/colloquium. Most of these may be way over your head, but they tend to cover a lot of research front areas of physics. You might also get some flavor if some of these research work are either done, or of some interest, at your school. The point here is that you need to start distinguishing yourself slowly by this time. The faculty in your department should not just see you during class time.

The next part of this essay applies only to US universities and to US citizens/permanent residents. If your school lacks the research work that are of any interest to you, or if you want additional experience over the summer holidays, then you may want to consider applying for the summer internship programs provided by the US Dept. of Energy. This provides an excellent opportunity for you to work at a world-renowned facility with practicing physicists. You may find the necessary information at the DOE website below:

http://www.scied.science.doe.gov/scied/sci_ed.htm

Keep in mind that competition for the internship is very intense. So, apply early!

In the next installment of this series, we address the final year of your undergraduate life, and the looming reality of either joining the rat race, or continuing on to graduate school.

Zz

Thursday, August 26, 2004

So You Want To Be A Physicist - Part 3

In most universities in the US, a student must have a declared major by the end of his or her second year. So this is an important transition - making the commitment in a particular area of study. By now, if you have followed the first two chapters of this series, you would have been aware of the necessary background to pursue your academic life in the physical sciences or engineering. All the discussion that we have had so far has been "generic" to a large variety of field of studies. However, at this point, this discussion will be more specific towards being a physics major.

The end of your second year marks the beginning of a more advanced undergraduate physics courses. You will probably no longer be in the same classroom as other majors, and most of your classes will comprise of only physics majors. This part of the series will focus on additional preparation you should have to be able to sail through your advanced undergraduate physics courses.

It was alluded to in a previous posting on here of having sufficient mathematical background. It has often been said that a physics major sometime needs more mathematics than even a mathematics major. Mathematics is viewed as a "tool" that physicists use in describing and analyzing physical phenomena. So one just never know what tools are needed for which job. This means that a physics major must have a wide ranging knowledge of different areas of mathematics, from differential equations, linear algebra, integral transforms, vector calculus, special functions, etc. These are the mathematics a physics major will encounter in courses in classical mechanics, electromagnetic fields, and quantum mechanics. Unfortunately, most physics majors do not have the inclination, nor the time, to be able to take all the necessary mathematics classes. What typically happens is that they learn the mathematics at the same time they are learning the physics. This is an unfortunate way to learn the material, because more often than not, the mathematics gets in the way of understanding the physics. It is hard enough to learn the physics, but having to also learn the mathematics simultaneously makes the problem rather daunting.

Many physics departments are aware of such problems, and one of the remedies is to offer a course in mathematical physics. This is typically a 1 year, 2 semester course covering a wide range of mathematics that a physics major will need. The purpose of such a course is to give a brief introduction to various areas of mathematics, not from the point of view of rigorous proofs and derivations, but from the point of view of how to use them effectively and correctly, especially when applied to actual physics problems. If there is such a course at your school, I highly recommend that you enroll for it as soon as you can, especially before you need them in your physics classes.

That last part, however, can be a problem. I have observed that in many schools, a mathematical physics course tends to be offered late in undergraduate program, or even as a graduate course. This, of course, does no good for someone wanting to learn the mathematics before one needs it. If this is the case, I would strongly suggest that you purchase this text: "Mathematical Methods in the Physical Science" by Mary Boas (Wiley). If you are a regular to our IRC channel, you would have seen me recommending (threatening?) this text to several people. This book is meant for someone to start using at the end of the 2nd year, and can be used as a self-study. It doesn't require the mathematical sophistication that other similar books require, such as Arfken. Furthermore, the Students Solution Manual that suppliments the text is a valuable book to have since it shows the details of solving a few of the problems. I would recommend getting both books without the slightest hesitation.

Knowledge of computers is almost a "given" nowadays. However, in physics, this goes a step further. No matter which area of physics you intend to go into, you MUST know (i) how to program and (ii) how to do numerical analysis/computaton. The first part is automatic. Most schools require at least a class in computer programming, using a favorite computer language. Most areas in the field of physics, FORTRAN is still in wide usage, C is a language that is gaining in popularity, and C++ is beginning to take hold. I suggest that the minimum number of programming language you should at least have a working knowledge of is 2: Fortran and C.

The 2nd part of programming, numerical analysis, isn't as automatic. This is the part most computer science majors do not do, but where most physics, mathematics, and engineering majors, have to do. In many instances, the mathematics that describe a physical system is not solvable analytically. This may be in the form of large matrices, non-linear differential equations, etc. In those cases, one can only find values out of the mathematics by solving them numerically. Learning the mathematics of numerical analysis is an extremely valuable skill for your academic knowledge, and even for your "marketability" to be employed. Do not be surprised if a few of your courses require a class project involving numerical computing of physical systems. Whether you intend to be an experimentalist or a theorist, you will need to know how to perform numerical computation.

To give students such skill, most schools offer a specific course in computational physics (in some cases, this is a specific area of study in itself at the graduate level). However, sometime such a course is not offered by the physics department, but rather by either the mathematics department (as a numerical analysis course) or the engineering department. Either way, you need to make sure you get a formal education in one of these, especially if it isn't part of a required set of classes that you have to take.

In the next installment of this series, we will discuss on the most important people in your life as a physics major: your adviser, your instructors, and your teaching/laboratory assistants.

Zz.

Wednesday, August 25, 2004

So You Want To Be A Physicist - Part 2

So now you're in college, and you have every intention to be a physics major (actually, what I'm about to describe applies to anyone who is taking a physics class, not just for physics majors). In most US universities, as a freshman, you do not have a major-specific academic advisor, mainly because most freshmen do not have an officially-declared major. What you would probably get during your first week is a "generic" advising based on what you INTEND to go into. In all likelyhood, assuming that you have all the necessary background, it is a safe bet that you would need the complete sequence of Calculus (typically a year, or 3 semesters worth). This would cover all the basic calculus and analytical geometry (level of Thomas-Finney), and towards the end of the sequence, may superficially cover more advanced topics such as vector calculus and partial differential equations. As a physics major, you will need more mathematics than this, and that includes a separate mathematics course in the two advanced topics that I have mentioned, and maybe even a course an complex analysis. These are the courses that you may have to take after you complete the calculus sequence (more discussion on mathematics in the next installment of this series).

The introductory physics courses can vary from school to school. Typically, the broad dichotomy would be Intro Physics with or without calculus. As a physics major, you would take the former. This means that, if you do not have any calculus background, you may have to delay your first physics class after you have at least completed the first semester of your calculus class (high-school students, take note of this!). The typical intro physics courses in US universities would be at the level of Halliday-Resnick. It is typically covered in 2 or 3 semesters and is intended to be a general survey of many different aspects of physics. These courses tend to be accompanied by laboratory work, which is intended to be an introduction to a systematic experimental study of various physics concepts.

I would like to expand on the importance of such laboratory work, mainly because for many students, this is looked upon as a waste of time, especially if the experiments and laboratory conditions are less than ideal. There are certain things that cannot be taught, but can only be acquired. These are what we call skills. The reason why one has to physically DO something during a laboratory session is to acquire such skills. This does not just mean physical skill, such as the ability to read an ammeter, to be able to perform a task with the least amount of errors, etc., but also mental skills, such as the analytical ability to look at the object of the experiment and figuring out why certain things are done certain ways. This includes the ability to critically analyze the experimental data and how to extract relevant information. Upon completion of such exercise, one must then be able to clearly explain in words and pictures (graphs) what one did, and the results. Again, such ability is important for obvious reasons and it is a skill that can't be taught. It can only be acquired through practice!

Note that what I have described above is not just applicable to physics majors. Such skills that can be acquired are important to anyone, regardless of one's major. In fact, I would make the assertion that acquiring such skills is MORE important for most students in a physics class than knowing the material. It is a fact that the majority of students in a physics class are not physics majors. Although the knowledge of physics is important as a foundation for other classes, for most of the students, the skills that can be acquired through physics classes and laboratories are the more valuable traits that they will carry with them throughout their academic life and beyond. The ability for critical analysis and knowing the reliability of data and results are important skills that are useful in all everyday life.

If you are an undergraduate in a US university, there is no excuse for not enrolling yourself in The Society of Physics Students (SPS). This organization is open to all students, not just physics majors. As part of your membership dues, you get a year's subscription to Physics Today, a journal that practically all physicists read and contains timely information on the world of physics and physicists. You will also get a newsletter and information specifically targeted for undergraduates like you, and also entitles you later on for significant discounts and even free registrations to attend various physics conferences. In other words, if you have even half a brain, enroll in this! The benefits are just too great to not to. Go to the physics department at your school and ask if they have a chapter of the SPS there. You can enroll via your school's chapter. If there isn't any, go to the SPS website at

http://www.aip.org/education/sps/index.html

and you may enroll there as an individual member. It is NEVER too early to be a member, so do it as soon as you are settled. If you are not in a US university, you may still subscribe to Physics Today by going to their website at

http://www.aip.org/pt/

Throughout your first 2 years, the BEST thing you can do for yourself is to get excellent grades. This, I'm sure, goes without saying, but you have to realize that typically, these are the easiest and the most important courses you will see in your undergraduate years. They are the foundation that you will build upon for your other courses, and they are the ones you have a better chance of achieving the highest grades. Do not be discouraged if you feel that at this stage, you are one of the many anonymous "numbers" in a large class. Most classes at this level tend to be huge and it isn't easy to distinguish oneself from the crowd (you will have plenty of opportunities to distinguish yourself later on). But do not let this stop you from seeing the instructor during his/her office hours, or using the Teaching Assistants if you need help. They have been PAID to do just that!

In the next installment, we will discuss the transition between the intro classes and the more advanced undergraduate classes, and your first tentative steps towards distinguishing yourself from other students.

Zz.

Tuesday, August 24, 2004

So You Want To Be A Physicist - Part 1

Most of us have various reasons or impetus for wanting to go into this profession. I sometime liken it to wanting to be a priest (I have a bad joke to accompany that, but I won't say it) - the calling towards it that somehow can't be ignored. We all know that being a physicist would not make us filthy rich, but there is somehow an intrinsic satisfaction working in this field.

In this part of the series, I'd like to start at the beginning. No, not during conception, or while one is still in the womb (although it isn't too late to read to a fetus about Newton's Laws of motion). The preparation one makes while still in high school before proceeding to college can be important. The most important of which, in my opinion, is one's mastery of basic mathematics. Typically, by the time someone enters college, there should already be a good command of algebra, trigonometry and geometry. Taking intro physics without a good command of these three is a recipe for disaster. In many cases, one also needs at least a semester's worth of calculus if the intro physics class includes calculus.

Although this appears to be obvious, it isn't. In my brief teaching experience at the freshman level (1st year students in a university in the US), I often found that many students struggled with their physics homework not because they did not understand the physics, but they could not do the mathematics. Of course, they then blamed the difficulty of physics for this without realizing that the physics course itself was not to be blamed. Interestingly enough, we often encounter similar situation on our IRC channel. Students coming in with physics problems are often stuck more with the mathematics.

So, adequate preparations in mathematics at the high school level is crucial. In the US, one can still catch up on the necessary basic mathematics even after enrolling in a university by taking which ever mathematics courses that one needs. However, this will mean delaying other physics courses till one has the necessary mathematics skill.

Are high school physics classes necessary? Definitely. It is always advantageous to have a flavor of the simple ideas of physics before hand. In the US, there is such a thing as AP Physics, where high school students get advanced physics lessons almost at the college level of intro physics. This can do nothing but add to one's advantage.

Unfortunately, sometime these high school physics classes can backfire. It is a sad reality that in many high school in the US, the physics classes are often taught badly, and often by someone without a physics degree. This has the negative effect of turning many students off this subject. Ask anyone who hates physics and chances are, they had a bad introduction to it in high school.

In Part 2, surviving the first year of college.

Zz.

So You Want To Be A Physicist

One of the most frequent questions we get (besides the annoying "can anything travel faster than c?" or "shouldn't light have mass since E=mc^2?") is the process and background of being a physics major. Often, we have students asking what are the requirements of obtaining a physics degree, and what can one do with such accomplishments.

I am hoping that, in a series of postings on this topic, we get to go over and demystefied the whole process of what one can expect as a physics major in college, all the way to going through a Ph.D program, and even beyond that in the land of postdoctoral work and employment. This is not as easy as it sounds, especially considering the wide-ranging educational systems we have throughout the world. So in most cases, the perspective I will tend to have the most understanding with is the US educational system. This is where someone from another country can come in and contribute their experiences and wisdom.

What I hope to impart is not only what is known, as described in various brochures and guidelines from many schools, but also what is never told to the students. Most of these come from personal experience, things that I found myself saying "Boy, I wish someone would have told me that earlier!".

As usual, feedback and questions are welcomed as this series progresses. Who knows, maybe after this, I may finally be inclined to compile all this into the book that I've always wanted to write! :)

Zz.