Current Thoughts in String Theory

DrLudicrous writes "The NYTimes is running a nice little synopsis of the current ideas in string theory. Apparently, there is still quite a bit of disagreement about how to interpret the various theories, with some string theorists supporting a semi-deterministic worldview a la Einstein (God does not play dice), while others believe our universe is just one possibility among many, with respect to various physical parameters."

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Free Link

[Anonymous Coward]

Link

Mirror

[Anonymous Coward]

In case the site is slow, or you don't have a stinking NYTIMES account, here is a mirror.

Martin Studio Slashdot Policy

Good Info on String theory

[gsparrow]

This site is maintained by a professor and has a great book on string theory. http://www.mkaku.org/

Yes but no

[Raul654]

You are correct in stating that we lack the energy to test string theory -- According to Hawking, one estimate of the (theoritcal) grand unification energy would be a thousand million million million GeV. Further, he goes on to say that it would take something the size of a solar system to produce this. So you're right, we can't do it.

BUT, there could very well be places that do have this necessary energy and could be observed to exhibit traits that we can measure and confirm theories with. This has been how most of the more recent unification theories have been confirmed -- either by measuring very small things with very fine equipment or measuring very large things in space.

Re:Fringe science, or valid?

[Eric Ass Raymond]

Enstein's theories were also empirically unprovable until recent advances in avionics, minaturization, and electronics.

Bollocks. Einstein's relativity could be readily tested at the time by measuring the bending of the light by Sun's gravity. That's exactly what made them so strong and actually respected by the experimentalists.

To an experimentalist a theory is just hot air until it can be tested in practise.

Re:Fringe science, or valid?

[henrygb]

Curiously, three independent experiments were undertaken at the next suitable solar eclipse to look at starlight being bent round the sun. One failed (cloud?), one produced results broadly consistent with General Relativity, and one produced results broadly consistent with Newtonian gravity applied to light.

The conclusion at the time was that General Relativity was confirmed, because the likelihood of measurement or equipment error seemed to have been greater with the result consistent with Newtonian gravity.

Primer to get you up to speed on current theory

[Nova Express]

I know more about string and particle theory than 99% of the population, which means I'm still a comparative dumbass on the subject in relation to people who really know what they're talking about.

However, here's a spiffy chart of the current "standard model" to help people get up to speed. Especially helpful for those who don't normally deal with Mesons and Antibayrons on a regular basis...

Re:Fringe science, or valid?

[Idarubicin]

Einstein's theories were also empirically unprovable until recent advances in avionics, minaturization, and electronics. It turns out, decades after he began to speak about 'Special Relativity', you can indeed fly an atomic clock around the world and measure that it has undergone relativistic time dialation.

Einstein's General Theory of Relativity provided an explanation for the motion of the perihelion of Mercury's orbit. Further, it correctly predicted the magnitude of this motion--all of about 43 seconds of arc per century. It's a small motion, but it had been observed, measured, and puzzled at by astronomers in the nineteenth century.

Aside: Many people cite the 1919 eclipse observations made by the Royal Astronomical Society (also mentioned in the link above) as a further early proof of relativity. Though this is the most popular early 'proof', it is tainted with uncertainties. More recent work suggests that the precision of the RAS' instruments was insufficient for the task--the good agreement with theory was likely largely coincidence. Indeed, contradictory results from later eclipses and other groups did follow in succeeding decades. (Measurements with modern instruments have, of course, borne out relativity.)

Superstring theory is not the only candidate

[az4 h0th]

You may also be interested in reading about loop quantum gravity, an alternative theory of everything. I' not expert, better refer to this reference that I looked up.