Ulmo
Jul2-04, 04:39 AM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>Davor <djagt@allstream.com> wrote in message news:<63ac5efc.0406270959.56d4a082-100000@posting.google.com>...\n> A few ideas clicked into place for me a little while ago while I was\n> having lunch and reading a book (Alastair Reynolds\' Absolution Gap pg\n> 334). It has to do with extra dimensions, dark matter and energy and\n> why gravity doesn\'t fit current Theory of Everythings (except String\n> Theory, which is why I am posting here).\n>\n> Local galaxies have been observed where stars in the outer edges of\n> those galaxies are rotating faster around the galaxy then they ought\n> to be, as theory would account for given the estimated mass of the\n> universe. And not just a bit faster but a lot faster.\n> Astrophysicists add Dark Matter to the equation to account for this\n> extra speed. Basically saying that if there was extra mass then\n> theory could account for the speed of those stars. But they cannot\n> see the mass, hence the term Dark Matter, matter that doesn\'t interact\n> with ordinary matter.\n>\n> This is where extra dimensions come into the picture, because Dark\n> Matter exists in these dimensions, but not our own. The only way we\n> can interact with Dark Matter is gravitationally. The reason that the\n> matter we are made of cannot interact with Dark Matter is that the\n> forces that make us up are confined to our set of dimensions, where\n> the forces that make up Dark Matter are confined to another set of\n> dimensions (and have different characteristics, more on this later).\n> But gravity, which puzzled scientists by being billions of times\n> weaker in comparison to say, the electromagnetic force, gravity\n> operates in all the dimensions, it only appears weak to us when\n> compared to the confined forces. One operates in all 10 or 11\n> dimensions (I forget which) while the others operate in only 4, the\n> familiar length, width, breadth and time. Of course its weaker, for\n> every unit of distance it travels its being spread across many more\n> dimensions.\n>\n> So how do we know that Dark Matter is in dimensions other then our\n> own? Models of the mass distribution necessary to account for the\n> observed galatic revolutions have been made. They show a diffuse mass\n> around and through the galaxy. Since regular matter and Dark Matter\n> interact gravitationally, its expected that they would be attracted.\n> But the fact that the Dark Matter is diffuse and spread out, points at\n> different physical laws governing its interactions with itself. Some\n> force or forces we can only imagine are preventing this Dark Matter\n> from collapsing into dense conglomerations like our suns and planets.\n> We see an indication of this in the fact that the planets in our solar\n> system are orbiting the sun in a fashion perfectly accounted for by\n> theory. So Dark Matter is prevented somehow from condensing this far.\n> The forces operating in the Dark Matter dimensional framework are\n> counterparts of the familiar forces operating in ours, but they would\n> have to differ in some dramatic way as a consequence of having to work\n> in those tightly curled dimensions.\n>\n> It all seems to hang together. But tell me what I have gotten wrong,\n> whats obviously egregious.\n\n\nI don\'t see any point to your idea at all. Why suggest that the dark\nmatter moves freely through extra dimensions? What would be the\nbenefit of that? Why not just say that it exists in the same\ndimensions that we do, but that we only detect it gravitionally? This\nis what cosmologists actually say. What is the point of suggesting\nthat it can propogate through higher dimensions?\n\nPhysicists don\'t just make up stuff for the hell of it. We invent\ntheories to try to explain something.\n\nAlso, you are obviously confusing the brane world scenario, where\nfermions and gauge bosons are confined to the brane while gravitons\ncan propogate freely, with traditional string theory where the extra\ndimensions are compacified on the planck scale. In normal string\ntheory, all particles "work in those tightly curled dimensions."\n\nDavid\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>Davor <djagt@allstream.com> wrote in message news:<63ac5efc.0406270959.56d4a082-100000@posting.google.com>...
> A few ideas clicked into place for me a little while ago while I was
> having lunch and reading a book (Alastair Reynolds' Absolution Gap pg
> 334). It has to do with extra dimensions, dark matter and energy and
> why gravity doesn't fit current Theory of Everythings (except String
> Theory, which is why I am posting here).
>
> Local galaxies have been observed where stars in the outer edges of
> those galaxies are rotating faster around the galaxy then they ought
> to be, as theory would account for given the estimated mass of the
> universe. And not just a bit faster but a lot faster.
> Astrophysicists add Dark Matter to the equation to account for this
> extra speed. Basically saying that if there was extra mass then
> theory could account for the speed of those stars. But they cannot
> see the mass, hence the term Dark Matter, matter that doesn't interact
> with ordinary matter.
>
> This is where extra dimensions come into the picture, because Dark
> Matter exists in these dimensions, but not our own. The only way we
> can interact with Dark Matter is gravitationally. The reason that the
> matter we are made of cannot interact with Dark Matter is that the
> forces that make us up are confined to our set of dimensions, where
> the forces that make up Dark Matter are confined to another set of
> dimensions (and have different characteristics, more on this later).
> But gravity, which puzzled scientists by being billions of times
> weaker in comparison to say, the electromagnetic force, gravity
> operates in all the dimensions, it only appears weak to us when
> compared to the confined forces. One operates in all 10 or 11
> dimensions (I forget which) while the others operate in only 4, the
> familiar length, width, breadth and time. Of course its weaker, for
> every unit of distance it travels its being spread across many more
> dimensions.
>
> So how do we know that Dark Matter is in dimensions other then our
> own? Models of the mass distribution necessary to account for the
> observed galatic revolutions have been made. They show a diffuse mass
> around and through the galaxy. Since regular matter and Dark Matter
> interact gravitationally, its expected that they would be attracted.
> But the fact that the Dark Matter is diffuse and spread out, points at
> different physical laws governing its interactions with itself. Some
> force or forces we can only imagine are preventing this Dark Matter
> from collapsing into dense conglomerations like our suns and planets.
> We see an indication of this in the fact that the planets in our solar
> system are orbiting the sun in a fashion perfectly accounted for by
> theory. So Dark Matter is prevented somehow from condensing this far.
> The forces operating in the Dark Matter dimensional framework are
> counterparts of the familiar forces operating in ours, but they would
> have to differ in some dramatic way as a consequence of having to work
> in those tightly curled dimensions.
>
> It all seems to hang together. But tell me what I have gotten wrong,
> whats obviously egregious.
I don't see any point to your idea at all. Why suggest that the dark
matter moves freely through extra dimensions? What would be the
benefit of that? Why not just say that it exists in the same
dimensions that we do, but that we only detect it gravitionally? This
is what cosmologists actually say. What is the point of suggesting
that it can propogate through higher dimensions?
Physicists don't just make up stuff for the hell of it. We invent
theories to try to explain something.
Also, you are obviously confusing the brane world scenario, where
fermions and gauge bosons are confined to the brane while gravitons
can propogate freely, with traditional string theory where the extra
dimensions are compacified on the planck scale. In normal string
theory, all particles "work in those tightly curled dimensions."
David
> A few ideas clicked into place for me a little while ago while I was
> having lunch and reading a book (Alastair Reynolds' Absolution Gap pg
> 334). It has to do with extra dimensions, dark matter and energy and
> why gravity doesn't fit current Theory of Everythings (except String
> Theory, which is why I am posting here).
>
> Local galaxies have been observed where stars in the outer edges of
> those galaxies are rotating faster around the galaxy then they ought
> to be, as theory would account for given the estimated mass of the
> universe. And not just a bit faster but a lot faster.
> Astrophysicists add Dark Matter to the equation to account for this
> extra speed. Basically saying that if there was extra mass then
> theory could account for the speed of those stars. But they cannot
> see the mass, hence the term Dark Matter, matter that doesn't interact
> with ordinary matter.
>
> This is where extra dimensions come into the picture, because Dark
> Matter exists in these dimensions, but not our own. The only way we
> can interact with Dark Matter is gravitationally. The reason that the
> matter we are made of cannot interact with Dark Matter is that the
> forces that make us up are confined to our set of dimensions, where
> the forces that make up Dark Matter are confined to another set of
> dimensions (and have different characteristics, more on this later).
> But gravity, which puzzled scientists by being billions of times
> weaker in comparison to say, the electromagnetic force, gravity
> operates in all the dimensions, it only appears weak to us when
> compared to the confined forces. One operates in all 10 or 11
> dimensions (I forget which) while the others operate in only 4, the
> familiar length, width, breadth and time. Of course its weaker, for
> every unit of distance it travels its being spread across many more
> dimensions.
>
> So how do we know that Dark Matter is in dimensions other then our
> own? Models of the mass distribution necessary to account for the
> observed galatic revolutions have been made. They show a diffuse mass
> around and through the galaxy. Since regular matter and Dark Matter
> interact gravitationally, its expected that they would be attracted.
> But the fact that the Dark Matter is diffuse and spread out, points at
> different physical laws governing its interactions with itself. Some
> force or forces we can only imagine are preventing this Dark Matter
> from collapsing into dense conglomerations like our suns and planets.
> We see an indication of this in the fact that the planets in our solar
> system are orbiting the sun in a fashion perfectly accounted for by
> theory. So Dark Matter is prevented somehow from condensing this far.
> The forces operating in the Dark Matter dimensional framework are
> counterparts of the familiar forces operating in ours, but they would
> have to differ in some dramatic way as a consequence of having to work
> in those tightly curled dimensions.
>
> It all seems to hang together. But tell me what I have gotten wrong,
> whats obviously egregious.
I don't see any point to your idea at all. Why suggest that the dark
matter moves freely through extra dimensions? What would be the
benefit of that? Why not just say that it exists in the same
dimensions that we do, but that we only detect it gravitionally? This
is what cosmologists actually say. What is the point of suggesting
that it can propogate through higher dimensions?
Physicists don't just make up stuff for the hell of it. We invent
theories to try to explain something.
Also, you are obviously confusing the brane world scenario, where
fermions and gauge bosons are confined to the brane while gravitons
can propogate freely, with traditional string theory where the extra
dimensions are compacified on the planck scale. In normal string
theory, all particles "work in those tightly curled dimensions."
David