Open Questions

A place for everyone to explore on the frontiers of science

Questions by field

Physics and Astronomy
Life Sciences
Earth and Environmental Science

Site map
About this site
Open Questions Chronicle
Addtional information...
This site has been designed to organize scientific information, both on and off the Web, around a number of fundamental "open questions" - the questions that motivate leading edge basic scientific research.

By exploring the pages here you can gain an understanding of many of the questions that still represent major mysteries even to top scientists. You'll find that you need not be concerned if you don't immediately recognize all the terminology of any particular field. Many of the resources collected here contain tutorial presentations which provide needed background. We've added a good deal of commentary of our own to get you started and point out the basic landmarks.

Enjoy the trip!

Important Note About This Site

This is, obviously, a rather large-scale project. As such, it is far from complete, not that it ever could be.

Although there is much still to be done in this part of the project, you should visit the related blog Science and Reason for detailed reports of the latest research developments in many of the areas covered here.

Another resource here that is complete, up-to-date, and quite detailed is the Open Questions Chronicle, which is a weekly list of important news stories relevant to the major open questions covered here.

The overall objective of this site is to provide several types of resources regarding the major open questions of science:

  • Survey articles about the major open questions, grouped into over 130 topic areas, together with overviews of the associated scientific field
  • Links to external Web sites dealing with each topic
  • Lists of relevant magazine and journal articles on each topic
  • Bibliographies of relevant books on each topic and its associated field
The lists of external Web links, magazine articles, and books are complete enough to be useful for most topics. The survey articles are much less complete. At present, the subject areas of high-energy physics and mathematics have the largest number of relatively complete articles.

There are, additionally, other features of interest, such as links to external science news sites, glossaries of scientific terms, and a detailed index of topics and subtopics. Many such pages are far from complete, but it is hoped that what does exist may be of some use.

What is the answer?
In that case, what is the question?

Last words of Gertude Stein, according to Alice B. Toklas

There are no solved problems. There are only more-or-less solved problems.

Henri Poincaré

Thinking about science in terms of open questions

Asking questions is the very heart of the scientific enterprise. Quite literally, everything in science begins with the questions. There is a collection of loosely related techniques, known as "the scientific method", that have been developed over the years for answering sufficiently well-posed questions. But this isn't really the essence of science. It is the questions themselves which come first.

Not just any questions, however. In general, questions begin with words like "what", "when", "where", "how", "how big", "how many", and most importantly, "why". But not everything that has the grammatical form of a question is an appropriate -- or at least a useful -- scientific question. A certain precision is required of the language used to express the question. It may have taken curious minds centuries, or even millennia, for our understanding to acquire sufficient precision in order to ask the right questions.

Philosophy is the domain of endeavor which allows for the asking -- and consideration -- of almost any question. At least two conditions have to be met before we can advance from the philosophical consideration of interesting questions to actual scientific investigation of them. Philosophy is willing to consider questions purely abstractly using tools like logic and plausible conjecture. Historically, and even today, this had often been done with little actual observation of the phenomena we are trying to understand. This is not necessarily negligence on the part of philosophers. More often it simply reflects a lack of the technology necessary to make useful observations. Even today, we are left with little more than philosophical speculation regarding phenomena that we simply can't observe even indirectly. So a certain level of technology is the first condition.

The second condition is the development of precise and appropriate concepts with which to think about the questions of interest. This is an appropriate task of philosophy. Some of this process may occur concurrently with scientific investigation, but often it preceeds real science, sometimes even by centuries. It also happens at times that scientific progress cannot occur until unsuitable or inadequate philosophical concepts are replaced with something "better".

There is nothing more important in science than finding the "right" questions to ask at a given time. Framing questions in the best possible way is more important even than collecting piles of data or performing endless random experiments to "see what happens". Science advances most rapidly when attempting to answer such questions that are not too easy, not too hard, but "just right".

So to be "right" a question needs to be more than just sufficiently precise. Answers to questions that are too "easy" do not maximize the possible advancement of our potential knowledge. They fail to take advantage of useful new ways of looking at the world. On the other hand, questions that are too "hard" are either based upon an inadequate conceptualization of reality or else simply address issues in which our present ignorance is too deep or for which we lack the technology to make pertinent observations or experiments.

Listing and explaining the "right" questions for which we do not yet have good answers and which are neither too hard nor too easy -- the Open Questions of science -- is the purpose of this Web site.

Further information and available resources

Site map
Direct access to the information here.
More about this site
Some thoughts about the role and importance of questions in the scientific enterprise.
Getting the most out of this site
What to expect when exploring the Open Questions site.
The Open Questions Chronicle
A weekly summary of news related to the topics covered by this site.
Topic index
Alphabetical index of the main topics covered here.
Science news sites
Directory of sites providing science and technology news, in general and in specific categories.
The best science sites on the Web
Links to some of the best sites on the Web related to science, in the following categories: online periodicals, general Web sites, other indexes of science sites, and scientific question/answer sites.
Glossaries of scientific terms
Glossaries of terms in various categories available here and through external links.
Quotations relevant to science
A selection of illuminating quotes about science.
Recent changes to this site
Information about what's new at the site.

Contacting the Webmaster

We appreciate input from anyone about the contents and presentation of this site. Suggestions for quality additions to the list of recommended links, articles, and books are especially welcome, though we can't promise that the addition will always be made, since the goal is to offer the best references. If you want to get in touch, just send us email.

Unfortunately, because of time constraints, we are usually not able to answer questions about the scientific facts and theories presented here. One purpose of this site is to help you find such answers for yourself. If you are a student at any level of the educational system, please use the information here as preparation to availing yourself of the resources of your school, college, or university -- especially your teachers and local libraries.

There are many individuals and organizations on the Internet that are prepared to answer questions about specific topics. Some of these are listed on our subject-area pages. We also have a list of general Question and Answer Sites you can turn to.

Browser requirements

In general, this site is browser-agnostic. Very few sophisticated HTML constructs are employed. However, there is one important exception to this. In many of the mathematics pages, and some of the physics pages, a goodly number of special symbols are used. Only fairly recent browsers are capable of displaying all of these symbols. Netscape 6 browsers and above are known to be in this category, as are recent versions of Mozilla. Internet Explorer 6 and earlier versions are not adequate. To determine whether your browser can display the symbols, check here.

Copyright © 2002 by Charles Daney, All Rights Reserved