Wednesday, May 24, 2017

What Every Physics Major Should Know?

Chad Orzel took on the silly tweet posted by Sean Carroll on what HE thinks that every physics major should  know.

Over the weekend, cosmologist and author Sean Carroll tweeted about what physics majors should know, namely that "the Standard Model is an SU(3)xSU(2)xU(1) gauge theory, and know informally what that means." My immediate reaction to this was pretty much in line with Brian Skinner's, namely that this is an awfully specific and advanced bit of material to be a key component of undergraduate physics education. (I'm assuming an undergrad context here, because you wouldn't usually talk about a "major" at the high school or graduate school levels.)

I categorize the tweet by Carroll as silly because he has no evidence to back up WHY this is such an important piece of information and knowledge for EVERY physics major. I hate to make my own silly generalization, but I'm going to here. This type of assertion sounds like it is a typical comment made by a theorist working on an esoteric subject matter. There! I've said it, and I'm sure I've offended many people already!

I would like to make another assertion, which is that there are PLENTY (even majority?) of physics majors who got their undergraduate degree without "informally" knowing the meaning of "...the Standard Model is an SU(3)xSU(2)xU(1) gauge theory...", AND..... go on to have a meaningful career in physics. Anyone care to dispute me on that?

If that is true, then Carroll's assertion is meaningless, because there appears to be NO valid reason for why a physics major needs to know that. He/she needs to know QM, CM, and E&M. That much I will give. Orzel even listed these and other subject areas that a typical undergraduate in physics is assumed to know. But a gauge symmetry in the Standard Model? Is this even in the Physics GRE?

Considering that about HALF of B.Sc degree recipients in physics do not go on to graduate school, I can think of many other, MORE IMPORTANT skills and knowledge that we should equipped physics majors. We are trying to make physics majors more "employable" in the marketplace, especially in the private sector. Comments by Carroll simply re-enforced the DISCONNECT that many physics departments have in how they train and educate their students without paying attention to their employment possibilities beyond research and academia. This is highly irresponsible!

I'm glad that Orzel took this head on, because Sean Carroll should know better... or maybe he doesn't, and that's the problem!

Zz.

Thursday, May 18, 2017

"Difficult" and "Easy" Are Undefined

This post comes about because in an online forum, someone asked if it is "easier" to heat something than to cool it down. The issue for me here isn't the subject of the question, which is heating and cooling and object, but rather, that the person asking the question thinks that the "measure" here is the "easiness". I'm sure this person, and many others, didn't even think twice to realize that this is a rather vague and ambiguous question. After all, it is common to ask if something is easy or difficult. Yet, if you think about it carefully, this is really asking for something that is undefined.

First of all, the measure of something to be "easy" or "difficult" it itself is subjective. What is easy to some, can easily be difficult to others (see what I did there?). Meryl Streep can easily memorize pages and pages of dialog, something that I find difficult to do because I am awful at memorization. But yet, I'm sure I can solve many types of differential equations that she finds difficult. So already, there is a degree of "subjectiveness" to this.

But what is more important here is that, in science, for something to be considered as a valid description of something, it must be QUANTIFIABLE. In other words, a number associated with that description can be measured or obtained.

Let's apply this to an example. I can ask: How difficult or easy it is to stop a 100 kg moving mass? So, what am I actually asking here when I ask if it is "easy" or "difficult"? It is vague. However, I can specify that if I use less force to make the object come to a complete stop over a specific distance, then this is EASIER than if I have to use a larger force to do the same thing.

Now THAT is more well-defined, because I am using "easy" or "difficult" as a measure of the amount of force I have to apply. In fact, I can omit the use of the words "easy" and "difficult", and simply ask for the force needed to stop the object. That is a question that is well-defined and quantifiable, such that a quantitative comparison can be made.

Let's come back to the original question that was the impetus of this post. This person asked if it is easier to heat things rather than to cool things. So the question now is, what does it mean for it to be "easy" to heat or cool things. One measure can be that, for a constant heat transfer, how long in time does it take to heat or cool the object by the same change in temperature? So in this case, the measure of time taken to heat and cool the object by the same amount of temperature change is the measure of "easy" or "difficult". One can compare time taken to heat the object by, say, 5 Celsius, versus time taken to cool the object by the same temperature change. Now this, is a more well-defined question.

I bring this up because I often see many ordinary conversation, discussion, news reports, etc.. etc. in which statements and descriptions made appear to be clear and to make sense, when in reality, many of these are really empty statements that are ambiguous, and sometime meaningless. Describing something to be easy or difficult appears to be a "simple" and clear statement or description, but if you think about it carefully, it isn't! Ask yourself if the criteria to classify something to be easy, easier, difficult, more difficult, etc... etc. is plainly evident and universally agreed upon. Did the statement that says "such and such undermines so-and-so" is actually clear on what it is saying? What exactly does "undermines" mean in this case, and what is the measure of it?

Science/Physics education has the ability to impart this kind of analytical skills, and to impart this kind of thinking to the students, especially if they are not specializing in STEM subjects. In science, the nature of the question we ask can often be as important as the answers that we seek. This is because unless we clearly define what it is that we are asking, then we can't know where to look for the answers. This is a lesson that many people in the public need to learn and to be aware of, especially in deciphering many of the things we see in the media right now.

It is why science education is invaluable to everyone.

Zz.

Thursday, May 11, 2017

Initial Employment Of US Physics Bachelors

The AIP has released the latest statistics on the initial employment of Physics Bachelors degree holders from the Class of 2013 and 2014.

Almost half of the degree holders left school to go into the workforce, with about 54% going on to graduate school. This is a significant percentage, and as educators, we need to make sure we prepare physics graduates for such a career path and not assume that they will all go on to graduate schools. This means that we design a program in which they have valuable and usable skills by the time they graduate.

Zz.

Wednesday, May 10, 2017

Dad Sat In On Student's Physics Class

A dad finally had it with his son's disruptive behavior in a high school physics class, and finally made his threat came true. He sat next to his son during his physics class.

His dad explained that his son 'likes to be the life of the party, which gets him in trouble from time to time.'

'For some reason I said, "hey, if we get another call I'm going to show up in school and sit beside you in class,"' he said. 

Unfortunately for the 17-year-old, that call did come. 

The thing that these news reports didn't clarify is if this student does this in all of his classes. If so, why is the physics teacher the one one reporting? If not, why does this student only does this in his physics class?

Sometime, a lot of information is missing from a news report.

Zz.

Wednesday, May 03, 2017

The US 2017 Omnibus Budget

Finally, the US Congress has a 2017 budget, and this is the time that I'm glad they didn't follow the disastrous budget proposal of Donald Trump. Both NSF and DOE Office of Science didn't fare badly, with NSF doing worse than I expected. Still, what a surprise to see an increase in funding for HEP after years of neglect and budget cuts.

The Office of Science supports six research programs, and there were winners and losers among them. On the plus side, advanced scientific computing research, which funds much of DOE's supercomputing capabilities, gets a 4.2% increase to $647 million. High energy physics gets a boost of 3.8% to $825 million. Basic energy sciences, which funds work in chemistry, material science, and condensed matter physics and runs most of DOE's large user facilities, gets a bump up of 1.2% to $1.872 billion. Nuclear physics gets a 0.8% raise to $622 million; biological and environmental research inches up 0.5% to $612 million. In contrast, the fusion energy sciences program sees its budget fall a whopping 13.2% to $380 million.

It will continue to be challenging for physics funding during the next foreseeable future, but at least this will not cause a major panic. I've been highly critical of the US Congress on many issues, but I will tip my hat to them this time for standing up to the ridiculous budget that came out of the Trump administration earlier.

Zz.