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This is a fascinating anomaly, and totally worth studying. But my perspective as a physicist in a different but somewhat related field has always been to tentat

by Steuard 13y ago

This is a fascinating anomaly, and totally worth studying. But my perspective as a physicist in a different but somewhat related field has always been to tentatively assume it's just a statistical fluctuation. If you look at the graph at the bottom of the first page of this article, have a look at the error bars on those data points: every one of them is at least borderline consistent with the smooth theoretical curve. (Or, alternately, look at the light green region around the curve: that shows the unavoidable uncertainties that we expect based on our finite view of the universe. The points they're interested in almost all lie within that range.) So yeah: it's a neat possibility, and it's great that people are looking into models to explain this (and to search for related predictions they can test). But it's not significant at a level that should get non-cosmologists tremendously excited at this point.

graycat 13y ago
Okay, when I was in physics as a ugrad, it was a long time until the LHC! So, my understanding of the now hot topics is from little more than just layman reading! Or, as I can guess at Guth's inflation, there was a quark; space expanded explosively so that maybe any two 'sides' of the quark were pulled apart faster than the speed of light; so, the quark was split into two quarks, that is, some energy was converted into quark mass. But two quarks have an axis. Could that be the origin of the 'axis of evil'? Or, how the heck else to have Guth's inflation starting with the first split of something without having an axis, that is, in 3 space, a line for the axis and perpendicular to a plane? Or, from that first split that generated mass, how can we avoid an axis, sure, in some 'random' direction but, still, an axis?
- Steuard 13y ago
  The issue you're running into here is that you're focusing on the description of this physics in terms of particles. That's usually a very convenient perspective, but it tends to have issues when gravity/spacetime is doing weird things (or even in an accelerated reference frame, which is sort of the same thing). What you really want to focus on is the question, "What are the (quantum) fields doing during inflation?" Those fields will typically be in a state with a whole lot of symmetry, and only small, random fluctuations away from that state will lead to perturbations in the CMB. I might be able to frame this in the particle picture, too. The issue is that there wasn't just one quark! There's a whole intense thermal mass of quarks and other particles, and the energies are high enough (and times short enough) that more of them are being pulled from the vacuum and annihilating back into it all the time (this is largely a field-theory statement, I'm afraid). That mass of quarks is what's being pulled apart by inflation. So there's no single special original quark particle that triggers the whole thing. [Disclaimer: I'm not actually a cosmologist, so I welcome corrections on anything I've misstated there!]
  - selimthegrim 13y ago
    http://en.wikipedia.org/wiki/Affleck-Dine_mechanism http://en.wikipedia.org/wiki/Affleck-Dine_mechanism
  - graycat 13y ago
    Particle - field, okay. To me, a 'particle' is just a temporary entity that happens when a field has an 'interaction' and decides to have its wave function 'collapse' -- then it has a new wave function. I was trying to go back before there was a 'soup' of wave functions with lots of quarks or whatever the first 'particle' was. So, as I read Guth, there was a 'something', small enough to be essentially just a 'point', but with very high energy and energy density, and that density caused high space-time curvature, and the region with that high curvature expanded, explosively, on the way to something much flatter but much larger, in the first second so large as to be nearly as large as now and with density and curvature nearly as low as now. So, back to the 'beginning': There was just one particle/wave of very high energy in a very small region of very high curvature that got pulled by the expanding space-time and, presto, soon there was two particles or wave functions. That first separation is the one I am thinking about, and it had to have an axis. And nearly all I have is just layman's descriptions of the curvature, wave functions, Guth's expansion, etc. so am typing stuff I really don't know about! In some of the math, my real field, I'm solid enough, but for the physics -- no.

by Steuard 13y ago

graycat 13y ago

Okay, when I was in physics as a ugrad, it was a long time until the LHC! So, my understanding of the now hot topics is from little more than just layman reading! Or, as I can guess at Guth's inflation, there was a quark; space expanded explosively so that maybe any two 'sides' of the quark were pulled apart faster than the speed of light; so, the quark was split into two quarks, that is, some energy was converted into quark mass. But two quarks have an axis. Could that be the origin of the 'axis of evil'? Or, how the heck else to have Guth's inflation starting with the first split of something without having an axis, that is, in 3 space, a line for the axis and perpendicular to a plane? Or, from that first split that generated mass, how can we avoid an axis, sure, in some 'random' direction but, still, an axis?

Steuard 13y ago
The issue you're running into here is that you're focusing on the description of this physics in terms of particles. That's usually a very convenient perspective, but it tends to have issues when gravity/spacetime is doing weird things (or even in an accelerated reference frame, which is sort of the same thing). What you really want to focus on is the question, "What are the (quantum) fields doing during inflation?" Those fields will typically be in a state with a whole lot of symmetry, and only small, random fluctuations away from that state will lead to perturbations in the CMB. I might be able to frame this in the particle picture, too. The issue is that there wasn't just one quark! There's a whole intense thermal mass of quarks and other particles, and the energies are high enough (and times short enough) that more of them are being pulled from the vacuum and annihilating back into it all the time (this is largely a field-theory statement, I'm afraid). That mass of quarks is what's being pulled apart by inflation. So there's no single special original quark particle that triggers the whole thing. [Disclaimer: I'm not actually a cosmologist, so I welcome corrections on anything I've misstated there!]
- selimthegrim 13y ago
  http://en.wikipedia.org/wiki/Affleck-Dine_mechanism http://en.wikipedia.org/wiki/Affleck-Dine_mechanism
- graycat 13y ago
  Particle - field, okay. To me, a 'particle' is just a temporary entity that happens when a field has an 'interaction' and decides to have its wave function 'collapse' -- then it has a new wave function. I was trying to go back before there was a 'soup' of wave functions with lots of quarks or whatever the first 'particle' was. So, as I read Guth, there was a 'something', small enough to be essentially just a 'point', but with very high energy and energy density, and that density caused high space-time curvature, and the region with that high curvature expanded, explosively, on the way to something much flatter but much larger, in the first second so large as to be nearly as large as now and with density and curvature nearly as low as now. So, back to the 'beginning': There was just one particle/wave of very high energy in a very small region of very high curvature that got pulled by the expanding space-time and, presto, soon there was two particles or wave functions. That first separation is the one I am thinking about, and it had to have an axis. And nearly all I have is just layman's descriptions of the curvature, wave functions, Guth's expansion, etc. so am typing stuff I really don't know about! In some of the math, my real field, I'm solid enough, but for the physics -- no.