Colloquially, we use the word research to generally mean doing your own digging, studying, and analysis of a topic. For example “I need to research the best recipe for potato salad,” or “Go research what mayoral candidate you should vote for.” It usually starts with a question like “What’s the best potato salad?” Then you doing some searching and reading of articles, reviews, comments, and analysis by other people. Then based on that information, you can make a decision. In scientific research, it’s kind of the same idea. You ask a question (how or why does thing A cause effect B), then you do some reading on what’s been done in the area (Bob studied thing A and saw effect C. Tiffany saw effect B but with thing D). The last important step, making a decision, is where things depart from the common usage of research. After the reading step, there’s a test step where you use what you’ve read to try to answer your question, assuming it hasn’t been answered already. This involves doing experiments, getting data, wearing lab coats and the other trapping usually associated with the idea of scientific research. However, this is not usually the most important part. The important part is the analysis of the data and the drawing of fundamental data-backed conclusions to “make a decision” on the original question. It’s in this last conclusion step where science happens and is usually the hardest part for new students and researchers to grasp. Without a data supported conclusion, you just have a bunch of numbers that sort of say something, but you don’t really know the fundamental details.
At the university, there are usually 3 levels of research: undergrad, Masters, and Ph.D. They increase in difficulty, depth, and expectations. The level of detail expected can generally be broken up into the various steps in a given research effort: test and observation, correlation and comparison to known ideas, and proposal of new idea supported by the data.
The first, test and observation, is typically where undergrad research students function. Undergrads usually worked with or assist a graduate student. Assuming they’re not relegated purely to chores like cleaning test tubes, an undergrad’s main tasks are to assist with experiments. That may include sample preparation or experimental set up, test operation, and data collection. That’s what most people associate with research, the actual experiment. More experiences undergrads may move to the observation stage, also called data analysis. Here, you not only take the data, but you also try to process that data and look for trends or behaviors like does thing A cause effect B to increase or decrease. These are usually pretty straightforward observation. This is usually where an undergrad would end, since moving to the next step of correlation and comparison requires some specific knowledge of the subject the student may not have. And many undergrad thesis focus mainly on presenting data, trends, and maybe touching on possible causes based on existing knowledge.
The second step, correlation and comparison, is where Master’s research typically sits. To compare, you need to read and know what to compare against. Thus MS students is where a lot of literature reading begins. By reading and understanding the literature, you can make more educated arguments about your observations from the data. Often times MS research will use existing formulas and theories learned from the literature to support the conclusions. For example if you observe A causes B to increase, and you find that other people saw the same behavior in a similar but not the exact same experiment, then you could make the comparison to that work. Alternatively, your data may fit in the general trend of other people’s results, allowing you to correlate how much B should change for a given level of A. This level of research present a deeper understanding of the physics by using similar research and existing understanding and equations as a guideline for your work. You are still contributing new information to the greater body of knowledge, but there’s usually not enough time to try to develop new understanding and equations.
The last step, proposal of new ideas, is what’s required of Ph.D. students. A Ph.D. student has to do everything an undergrad or MS student does, but then has to go one step further. They must take the same data and observations, the existing understanding and equations, and discover new understanding or equations that describe the fundamental physics. Continuing the example of A causes B to increase, perhaps the existing understanding says it occurs because of a phase change in B. At the Ph.D. level, you must discover why does A cause B to change phase, that’s the fundamental physics. This is usually pretty hard and requires significant time investment to take careful measurements, analyze each set of tests to help determine what conditions to test next, and lot and lots of paper reading to understand what other people are saying or doing in your area. And there will be many set backs and errors along the way, resulting in redoing things until it’s right.
So in summary, the three level of research can be summed up generally in the questions of what, how, and why. What happens? How does it happen? Why does it happen? For a Ph.D. you have to answer all of those, and hopefully enjoy doing it, otherwise a research career may not be for you.