M-THEORY FOR THE LAYMANThe leading candidate for an all-embracing theory of physics, one that would unify quantum mechanics and Einstein's general relativity and describe all physical phenomena from quarks to the Big Bang, is called `M-theory', where M stands for magic, mystery or membrane, according to taste This kind of research is driven purely by curiosity about the universe we live in and has no immediate commercial, industrial or military applications. Consequently, it is under threat from the government’s ``impact agenda’’ which pressures the Research Council’s to abandon academic excellence as their prime criterion in deciding what projects to fund in favour of financial returns. (All three major political parties are just as bad in this respect.) In my opinion, this is not only bad science but bad economics: many of the discoveries that have had the greatest impact on society stemmed from fundamental research, but it is impossible to predict from where. For example, the World Wide Web was invented at CERN, the particle physics lab in Geneva. In any event, finding an all-embracing theory would be a triumph of human thought and well worth the effort, whether or not it leads to practical applications M-theory brings together two strands in theoretical research: (1) ``Supergravity’’, an extension of Einstein’s theory involving ‘’supersymmetry’’ that permits a maximum of eleven spacetime dimensions; (2) String theory, whose fundamental components are tiny vibrating strings. M-theory involves two-dimensional membranes or bubbles as well as one-dimensional strings. Is M really the final theory'? Decide for yourself: |
|
|
M-History Without the M |
|
A review of the book “A Brief History of String Theory: From Dual Models to M-Theory” by Dean Rickles.
|
|
String and M-Theory: Answering the CriticsUsing as a springboard a three-way debate between theoretical physicist Lee Smolin, philosopher of science Nancy Cartwright and myself, I address in layman’s terms the issues of why we need a unified theory of the fundamental interactions and why, in my opinion, string and M-theory currently offer the best hope. The focus will be on responding more generally to the various criticisms. I also describe the diverse application of string/M-theory techniques to other branches of physics and mathematics which render the whole enterprise worthwhile whether or not “a theory of everything” is forthcoming.
|
| ||
Benchmarks on the BraneBranes now occupy center stage in theoretical physics as microscopic components of M-theory, as the higher-dimensional progenitors of black holes and as entire universes in their own right. Their history has been a checkered one, however. Here we list some of the milestones, starting with Dirac’s 1962 paper. Asim Barut was an early pioneer.
|
| ||
The World in Eleven Dimensions: A Tribute to Oskar KleinCurrent attempts to find a unified theory that would reconcile Einstein’s General Relativity and Quantum Mechanics, and explain all known physical phenomena, invoke the Kaluza-Klein idea of extra spacetime dimensions. The best candidate is M-theory, which lives in eleven dimensions, the maximum allowed by supersymmetry of the elementary particles. We give a non-technical account.
An Appendix provides an updated version of Edwin A. Abbott’s 1884 satire Flatland: A Romance of Many Dimensions. Entitled Flatland, Modulo 8, it describes the adventures of a superstring theorist, A. Square, who inhabits a ten- dimensional world and is initially reluctant to accept the existence of an eleventh dimension. |
| ||
The Theory Formerly Known as StringsThe Theory of Everything is emerging as one in which not only strings but also membranes and black holes play a role.
|
| ||
A Layman's Guide to M-TheoryThe best candidate for a fundamental unified theory of all physical phenomena is no longer ten-dimensional superstring theory but rather eleven-dimensional M-theory. In the words of Fields medalist Edward Witten, “M stands for ‘Magical’, ‘Mystery’ or ‘Membrane’, according to taste”. New evidence in favor of this theory is appearing daily on the internet and represents the most exciting development in the subject since 1984 when the superstring revolution first burst on the scene.
|
| ||
Interview with Edward Witten |
| ||
Here comes hypertime, Michio Kaku |
| ||
Into the eleventh dimension, Paul Davies |
| ||
Godless universe |
| ||