Jump to content
Objectivism Online Forum
dianahsieh

Theory of Everything?

Rate this topic

Recommended Posts

By Paul from NoodleFood,cross-posted by MetaBlog

Physicist/surfer Garrett Lisi may have come up with a physics theory that unites all the fundamental particles and forces of nature, including gravity, without relying on dubious multidimensional string theory. According to this related article:

...[H]is proposal is remarkable because, by the arcane standards of particle physics, it does not require highly complex mathematics.

Even better, it does not require more than one dimension of time and three of space, when some rival theories need ten or even more spatial dimensions and other bizarre concepts.

In other words, it doesn't require invoking arbitrary new dimensions for which we have no evidence. Plus it makes testable predictions that are at variance with the so-called Standard Model. The New Scientist article states that his theory predicts:

...[M]ore than 20 new particles not envisaged by the standard model. Lisi is now calculating the masses that these particles should have, in the hope that they may be spotted when the Large Hadron Collider - being built at CERN, near Geneva in Switzerland - starts up next year.

"This is an all-or-nothing kind of theory - it's either going to be exactly right, or spectacularly wrong," says Lisi. "I'm the first to admit this is a long shot. But it ain't over till the LHC sings."

David Harriman mentioned in his lecture to our Front Range Objectivism group last year that any physicist who wants to challenge the dominance of string theory will have a very hard time, since nearly all the grant funding in academia for such foundational issues is controlled by people who believe in string theory. It seems that this is borne out by Lisi's experience, as reported by New Scientist:

Most attempts to bring gravity into the picture have been based on string theory, which proposes that particles are ultimately composed of minuscule strings. Lisi has never been a fan of string theory and says that it's because of pressure to step into line that he abandoned academia after his PhD. "I've never been much of a follower, so I walked off to search for my own theory," he says. Last year, he won a research grant from the charitably funded
Foundational Questions Institute
to pursue his ideas.

For those who are interested in the details of his theory, here's the link to his paper (click on "PDF" on the upper right). The abstract reads as follows:

An Exceptionally Simple Theory of Everything

A. Garrett Lisi (Submitted on 6 Nov 2007)

Abstract: All fields of the standard model and gravity are unified as an E8 principal bundle connection. A non-compact real form of the E8 Lie algebra has G2 and F4 subalgebras which break down to strong su(3), electroweak su(2) x u(1), gravitational so(3,1), the frame-Higgs, and three generations of fermions related by triality. The interactions and dynamics of these 1-form and Grassmann valued parts of an E8 superconnection are described by the curvature and action over a four dimensional base manifold.

Those who want a semi-technical explanation (with video) can find one here. My own mathematics background is not strong enough to make an assessment of the merits of his theory. Nor do I know any more about the Foundational Questions Institute besides what's on their webpage. But FWIW, I did meet Garrett Lisi at a dinner party several years ago as a friend-of-a-friend, back when Diana and I lived in San Diego and he was still a graduate student in physics at UCSD. At the time, he struck me as an extremely intelligent man, so he would be a plausible candidate for someone who could have come up with a revolutionary new theory in physics.187760443

http://ObjectivismOnline.com/archives/003014.html

Share this post


Link to post
Share on other sites

String theory is silly, but not as silly as the mystical Copenhagen interpretation.

I'm currently sold on David Deutsch's (tentative) unifying theory, as expounded in 'Fabric Of Reality', which harmonises the many-worlds interpretation of quantum mechanics with evolution and universal computation. The many-worlds interpretation seems to solve all those seemingly irrational paradoxes invoked by the Copenhagen interpretation of quantum mechanics.

Share this post


Link to post
Share on other sites

Oh but String Theory is so much FUN to consider. Especially when you extend it out to Brane theory!

You may say that, but another you in a parallel dimension (or maybe on a different membrane) may not find it fun at all.

j..

Share this post


Link to post
Share on other sites

.

A Geometric Theory of Everything

Garrett Lisi and James Owen Weatherall*

Scientific American – December 2010

Get it for six bucks on the stand now.

From the editors’ In Brief:

Most physicists think reconciling Einstein’s general relativity with quantum theory will require a radical shift in our conception of reality. Lisi, in contrast, argues that the geometric framework of modern quantum physics can be extended to include Einstein’s theory, leading to a long-sought unification in physics.

Even if Lisi turns out to be wrong, the E8 theory he has pioneered showcases striking patterns in particle physics that any unified theory will need to explain.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...