Today’s Hype

5 Responses to Today’s Hype

1. DB says:

   January 31, 2008 at 1:20 pm

   You might also get a kick out of US Patent#6025810 for a Hyper-Light-Speed Antenna which claims: “The present invention takes a transmission of energy, and instead of sending it through normal time and space, it pokes a small hole into another dimension, thus, sending the energy through a place which allows transmission of energy to exceed the speed of light.”

   http://www.patentstorm.us/patents/6025810-fulltext.html

   It reminded me of how Brown University’s Greg Landsberg, when interviewed by BBC Horizon’s Dr. Brian Cox earlier this week, explained that one of the reasons we may not see gravitons is that perhaps they spend most of their time in extra dimensions. (Incidentally the above patent reference turns up at the end of one of Landsberg’s old presentations here:
   http://hep.brown.edu/users/Greg/Talks/Moriond01.pdf)

   You can see the interview with Landsberg here (near the end):
   http://tinyurl.com/ywpu8j

   Apart from this, Tuesday’s Horizon programme was a pretty good and hype-free popular survey of the issues surrounding current efforts to detect gravitons.
2. Cornelius R. Morton says:

   January 31, 2008 at 4:06 pm

   Reference
   http://www.patentstorm.us/patents/6025810-fulltext.html

   The US Patent Office has just bent Special Relativity and certified the existence of higher dimensions!?! Also noted in the description that use of this device will stimulate plant growth. Why?
3. Coin says:

   January 31, 2008 at 5:08 pm

   Okay, now this one confuses me. So they are actually suggesting that the graviton is in the TeV range and could be detected at the LHC by the particles it decays into? I guess I don’t really know whether the idea of gravitons being generated in a particle accelerator is all that strange or not, but how’s the graviton-decay thing work? Shouldn’t gravitons be really really long-lived, like photons or something, in order for gravity to work in the first place?

   Or is the idea that their model somehow contains both “KK gravitons” and normal gravitons, and the KK gravitons are the ones that appear in the TeV range and decay quickly, and the normal gravitons just cause gravity? (Their cite, hep-ph/9909255, talks about there being a “tower” of gravitons somehow related to the different “KK excitations”, which seems to make it sound like there’s more than one kind of graviton; and searching there actually seem to be a lot of papers writing about the “KK graviton tower”. I don’t think I quite understand any of this. What’s a graviton “tower”?)

   Also why do they talk about “5-d warped extra dimensions”? Don’t we need ten for strings? Or do they just mean that among the six “extra” dimensions in the 10d string model, exactly five are warped?
4. Yatima says:

   January 31, 2008 at 5:25 pm

   Why?

   “As you know, Bob” the use of tachyonic communication devices causes resonant vibrations in the background pan-galactic morphogenetic flux field. This trivially causes water-protein complexes in plant tissue to undergo quantum algorithmic boost processes leading to hitherto unreached efficency in cell growth.

   At least one can definitly say that there is no “prior art”.

   (Sorry for the noise.)

   Anyway, Peter, I propose you add a “hype chart” to the blog sidebar for easier consultation, like they do at that “Homeland Security” outfit.
5. chethan krishnan says:

   February 1, 2008 at 5:40 am

   Dear Coin,

   Here is what people mean when they talk about a Kaluza Klein tower.

   The wave function for a field has to come back to its starting value when you move around a compact dimension (think of a circle) because wave functions are believed to be, well, functions, i.e., they are single-valued.

   Now, momentum is the generator for translations (which is just a fancy way of saying that i.p.x is what shows up in the exponent in the wave function, just believe me on this point if you don’t know why. I don’t know your background.). So this condition can be translated to the condition that momentum components in the compact dimenions are quantized as n/R, where R is the radius of the circle, and n is an integer. ( Because ip (x+2 pi.R) – ip x, should be a multiple of 2i pi. n)

   Now, if you write down the equation of motion for the field (example: think of a Klein-Gordon equation) the derivatives in the compact dimensions bring down (the square of) the quantized mometum and it looks just like a mass term. So if you want to talk about all the n’s together, we can talk about a “Kaluza-Klein tower” of fields. Depending on the size of the compactification, all of these except the n=0 (massless) case might be too heavy to be detected in accelerators. This is where “large” extra-dimensions etc. (larger size= smaller mass) can give rise to possibly new phenomenology.

   If you notice, I tacitly assumed that the compact dimension was flat. (Circles have zero intrinsic, i.e., Einstein-like, curvature). What the paper that you pointed to is considering, is the possibility that this need not be the case, you can consider more general spaces for compactification. The word warped means there are some conformal factors that show up in pieces of the metric. It turns out that this warping is a beautiful way in which we can explain away the heirarchy between say electroweak and Planck scales. The word “graviton” comes up because the higher dimensional metric, with some legs in the compact dimensions, is what get interpreted as lower dimensional fields.

   Randall-Sundrum as it is, is a phenomenological model. So it doesn’t have to be motivated by string theory. But the interesting thing is that it *is* motivated by string theory. Randall-Sundrum like scenarios are more or less easy to implement in string theory by considering one of the “compact” dimensions expected from of string theory to be non-compact, warped, etc.

   Of course this was just the general story, but that should give you the bearings.

   Chethan.

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