Essay Abstract

Abstract : It is proposed that existing theoretical frameworks, and existing and forthcoming data, arguably finally allow us to achieve a testable, final understanding of the string vacuum we live in, and its relation to ultimate questions.

Author Bio

Kane is Victor Weisskopf Collegiate Professor of Physics at the University of Michigan, and Director of the Michigan Center for Theoretical Physics. He has published nearly two hundred research papers, and written or edited nine books, two of which are for general readers.

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Dear Dr. Kane,

It is good to see you in this contest.

Of course, the Supersymmetric Standard Model makes important predictions that have not yet been disproven, and might ultimately represent our Universe.

I also agree on the relevance of String Theory, but the Standard Model seems to be an ugly but practical bottom-up theory, whereas String Theory is top-down in its formulation but plagued by lack of input parameters and data. Can the two theories really meet in the middle?

I see that I now need to read arXiv:0906.4765v3 as well - I always expected the LSP to be a photino/ neutralino, not a wino/ chargino. Perhaps Nature wanted to surprise us!

Good luck in the contest!

Ray Munroe

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Dear Dr. Kane,

Oops! Upon skimming your arXiv paper, I realize you are talking about a neutral wino LSP (in your Pamela abstract). I probably would have called it a zino or bino to minimize confusion with the charged wino. I see that a 180 GeV neutral wino fits much of the data, but we should expect this bino-neutralino to also have higgsino and trace amounts of photino characteristics. Can we fit the data better by mixing in some higgsino?

I don't think we ever met, but I studied under Howie Baer with your former post-doc, Mike Brhlik. Mike was a year behind me, but we were officemates.

You mention a string theory model compactified on a manifold with G2 holonomy. Lawrence Crowell (also in this contest) and I are also trying to build models that might connect with a multi-dimensional supersymmetric string theory on the high-energy side and the Standard Model on the low-energy side. Lawrence also has a G2 holonomy. I have a G2 buried in the Color theory component of my model, but can't decide if the SUSY part of my model is G2 or I2(7) (details in my Ref.3 - A Case Study 3.3.pdf posted on my essay blog site).

Be careful! There are rogues in this voting process. The majority of my votes have been 8's or 1's - they either love or hate me! It seems that you are getting the same response.

Good Luck!

Ray Munroe

Dear Professor Kane,

I read with interest your essay which I assume gives the state of the art of string theory tests. I must admit I'm a bit confused about your optimistic view on physics, with respect to the opinion expressed by Ginzburg in his 2003 Nobel lecture. His "we are facing a boundless sea of unresolved problems" contrasts so strongly with your "it is now finally possible to achieve a complete understanding of our universe and its underlying laws of nature within the next few years". I can hardly understand how the 6 years separating both statements have brought such a reversal. Maybe your statement relates only to the situation in string theory?

By the way, in order to promote the contest, I publish essay quotes on my twitter profile and blog. Would you mind if I quote some of yours (with a link to your essay of course)? For example : "What is exciting about string theory is that it addresses in one consistent framework all the questions we want to address about understanding our universe."

Regards,

Arjen Dijksman

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Hello dear Mr Gordon Kane,

Nice to meet you .

Interesting essay .Good luck for the contest .

hihihih and me who say ,it's the end of strings ....

Could you tell me what is exatly this vaccuum ?

And second what are these extra dimensions ,their physical rules and properties too ?

And finally what about the rotations ,the rotating quantum spheres for me implying mass ???

Best Regards

Steve

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Dear Dr. Kane,

I spent the day at the beach. And on my way home, I realized I had been very sloppy about my MSSM notation. For the sake of other blog readers, I will clarify.

In Electroweak, the neutral W and B mix with each other and with Higgs components to form the Z and photon. When we add SUSY to the picture, we mix neutral Wino (related to the Zino) and Bino (related to the photino) with a variety of Higgsinos to form four different Neutralinos. I probably would not have gotten confused if you had called it neutral wino every time (zino is a crude approximation of the neutral wino).

Have Fun!

Ray Munroe

8 days later

Gordon

I was a skeptic towards String Theory but your essay very lucidly gave me a view of it that was refreshingly understandable, pragmatic, and practical. I am now a "maybe it can make sense". Some comments:

1. Re the > 3 dimension issue. I am not sure we really understand what Dimensions are.

2. If I understood him correctly John Baez, at one time a leader in the opposing camp of QG, was against String Theory because it was not "Background Free". Obviously the issue of Dimensions is relevant to the background. Do you think ultimately the background issue will go away = be resolved ?

3. My chief criticism, as reflected in my essay, is that String Theory is "progressive' (and so is QG). That is it accepts the mathematical science inherited from its predecessors as sound but unfinished and needing progressive (only) revision. I give 10 elementary reasons why the accepted foundations are unreliable and we need a regressive revision before "ultimate" goals can be achieved. Any structure built on dodgy foundations must be suspect - even String Theory.

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I agree with Terry. String theory is not a background independend theory. M-theory is supposed to be background independend. I found a 16 dimensional classical relativistic background independend metric. In this metric there are only three spatial dimensions. Next to the vector quantity length l there are three more vector quantities: burst b, momentum p and quantity s. And 4 scalar quantities: time t, gmflux f, energy E and mass m. 10 dimensional string theory has no idea what to do with the supposed 9 spatial dimensions. So they rolled them to tiny circles. I think that Superstring theory is wrong about those 9 spatial dimensions. There are only three spatial dimensions.

The general metric could be the missing link. I wonder what will happen when this metric is incorporated into Stringtheory. According to Jens Koeplinger it is possible that my approach from the product of two octonions would not result in a spin 2 model. But better take a look at what Jens exactly said, so that he is not misunderstood.

But realise the consequences for both String theory and Quantum gravity when there is no graviton.

[math]t^{2}c^{4} - l^{2}c^{2} b^{2}c^{-2} - f^{2} = \left(\dfrac{G}{c}\right)^{2} (E^{2}c^{-4} - p^{2}c^{-2} s^{2}c^{2} - m^{2})[/math]

2 months later
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We are too tiny both space and time wise to comprehend the universe. But our mind / intellect exists to speculate about the Universe as well as to study it as best as we can. Some speculations were provided by this author in the last year's FQXI contest on the theme ' The Nature of Time'.With the lapse of one year, i wonder if i have leart any thing more. What i find is that i have learnt more how wrong i may be about the ideas i tried to present as 'perspectives'. Let me say how much i understand the concept of ' vacuum'? Is it just a volume of space free from any matter? Then what about the equivalence of matter and energy? Can space be really free from both matter and field? How can we sense the same with precision and surety? What is then the secret of vacuum in Physics? May be what lies in vacuum is the life force of the Universe itself? We go on looking at the matter and energy physically while the 'source in vacuum' continues to lie in the 'non-phyical' range as per our present day Physics. How wide can we make our methodology in Physics? May be we ourselves are restricting Its growth through the methodology that we think we have evolved for developing the same!

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