Mastering A Subject
To master a subject, a student searches the
published literature to find and read everything that has been written about
the subject. In scientific disciplines, a student begins by studying general
reference works such as text books. Eventually, the student must also search
scholarly journals, the publications that scientists use to exchange
information and record reports of their scientific investigations.
Each university establishes general
guidelines that a student must follow to earn a Ph.D. degree, and each college
or department within a university sets specific standards by which it measures
mastery of a subject. Usually, in preparing for Ph.D. work in a given field, a
student must earn both a Bachelor's and Master's degree (or their equivalent)
in that field or in a closely related field. To demonstrate complete mastery of
the subject, a student may be required to complete additional graduate-level
courses, maintain a high grade average, or take a battery of special
examinations. In many institutions, students must do all three.
Because examinations given as part of a
Ph.D. curriculum assess expert knowledge, they are created and evaluated by a
committee of experts, each of whom holds a Ph.D. degree.
Extending Knowledge
The essence of a Ph.D., the aspect that
distinguishes Ph.D. study from other academic work, can be summarized in a
single word: research. To extend knowledge, one must explore, investigate, and
contemplate. The scientific community uses the term research to
capture the idea.
In scientific disciplines, research often
implies experimentation, but research is more than mere experiments -- it means
interpretation and deep understanding. For Computer Scientists, research means
searching to uncover the principles that underlie digital computation and
communication. A researcher must discover new techniques that aid in building
or using computational mechanisms. Researchers look for new abstractions, new
approaches, new algorithms, new principles, or new mechanisms.
To complete a Ph.D., each student must
present results from their research to the faculty in a lengthy, formal
document called a dissertation (more popularly referred to as a thesis). The
student must then submit their dissertation to the faculty and defend their
work in an oral examination.
Relationship To Products
In some cases, the results of scientific
research can be used to develop new products or improve those that exist.
However, scientists do not use commercial success or potential commercial
profits as a measure of their work; they conduct investigations to further
human understanding and the body of knowledge humans have compiled. Often, the
commercial benefits of scientific research are much greater in the long-term
than in the short-term.
Research Activities
Computer Science research can include such
diverse activities as designing and building new computer systems, proving
mathematical theorems, writing computer software, measuring the performance of
a computer system, using analytical tools to assess a design, or studying the
errors programmers make as they build a large software system. Because a
researcher chooses the activities appropriate to answer each question that
arises in a research investigation, and because new questions arise as an
investigation proceeds, research activities vary from project to project and
over time in a single project. A researcher must be prepared to use a variety
of approaches and tools.