Expert: Philip A. Stahl - 12/8/2008

Question
Philip A. Stahl,
I appreciate the time you took to explain why you declined to answer my previous question about parallel universes, which actually gave me a pretty good answer to my question.

It is true that a lot of my exposure to science is via pop-formats, especially science shows on television.  
In fact, my question was prompted by a recent show hosted by Dr. Michio Kaku (referred to as a theoretical scientist by Wikipedia), in which I think he said that he personally believes in the likelihood of some of these theories.

My new questions are:  How do I distinguish between "pop" and real science on these shows?  Where does theoretical science fit into this?  Where does this put string, super string, and 'brane theories?

Thanks,
Paul

Answer
Hello,

These are all excellent questions. Unfortunately, it isn't always easy to discriminate between "pop science" and the real McCoy. Generally, the main criterion I use is to ask the question: Has the claim or proposal or hypothesis been published in a peer-reviewed journal or is it at least in a *preprint* format?

The archives for physics, etc. preprints (e.g. generally papers in the next to last stage of publication) may be found here:

http://arxiv.org/

.pdf documents can be downloaded, and even if most of the paper reads like "gibberish" to you, most of the paper's abstract may at least be understandable.


As for science TV shows, I have also viewed many of them (e.g. "The Elegant Universe" from PBS, featuring Brian Greene, as well as some spots by Kaku) but never treat these as the "last word" on any claim or proposal, say like string theory.

As for Kaku "believing in the likelihood or plausibility" of any or all of these, well - perhaps. But belief is not the ultimate litmus test for good science, or pedigree science. Rather, testability and confirmation is what we look for.

Lastly, theoretical science differs from "pop" content in that it at least has powerful and coherent mathematics to support it to some degree. Such is the case with string theory (and to a lesser extent its brane cousin) which is why I do not put them in the exact same box as parallel worlds. What string and brane theoretics lacks is a touchstone of testability in the real world. Maybe that day will soon come once they get the large hadron collider back up and running from next summer.

Hope this helps!