## Planck length calculated assuming D > 3 dimensions - would it be larger?

I'm reading Lisa Randall's "Warped Passages" and just finished Green's
"Fabric of the Cosmos". In both, they mention that it seems unusual
that gravity is so weak compared to the 3 other forces. One
speculative resolution is that there are in fact D dimensions (D = 10
or 11) and since we live in 3 space dimensions, we feel only part of
gravity's full strength and that's why gravity seems so weak.

That lead me to wonder whether the Planck length distance scale, which
is calculated using the D=3 gravitational constant, G, should actually
be calculated using gravitational constant assuming D space dimensions
(i.e., if we wrote the force of gravity as F = G(D) * M * m / r **
(D-1) in D dimensions) . I'm assuming that the gravitational constant
will reflect gravity's strength and thus be larger in D dimensions than
the value of G in 3 dimensions (Newton's gravitational constant) If
so, is there any way to speculate how much larger one might expect the
Planck length to be relative to the value of 1.6x10-35 m?

Thanks,

Ted

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 Actually, does Newton inverse distance law follows from Einstein Theory (Riemann Tensor based theory) for any dimension? teds@intex.com ha escrito: > I'm reading Lisa Randall's "Warped Passages" and just finished Green's > "Fabric of the Cosmos". In both, they mention that it seems unusual > that gravity is so weak compared to the 3 other forces. One > speculative resolution is that there are in fact D dimensions (D = 10 > or 11) and since we live in 3 space dimensions, we feel only part of > gravity's full strength and that's why gravity seems so weak. > > That lead me to wonder whether the Planck length distance scale, which > is calculated using the D=3 gravitational constant, G, should actually > be calculated using gravitational constant assuming D space dimensions > (i.e., if we wrote the force of gravity as F = G(D) * M * m / r ** > (D-1) in D dimensions) . I'm assuming that the gravitational constant > will reflect gravity's strength and thus be larger in D dimensions than > the value of G in 3 dimensions (Newton's gravitational constant) If > so, is there any way to speculate how much larger one might expect the > Planck length to be relative to the value of 1.6x10-35 m? > > Thanks, > > Ted
 wrote in message news:1139333220.668522.89400@g14g2000cwa.googlegroups.com... > I'm reading Lisa Randall's "Warped Passages" and just finished Green's > "Fabric of the Cosmos". In both, they mention that it seems unusual > that gravity is so weak compared to the 3 other forces. One > speculative resolution is that there are in fact D dimensions (D = 10 > or 11) and since we live in 3 space dimensions, we feel only part of > gravity's full strength and that's why gravity seems so weak. > > That lead me to wonder whether the Planck length distance scale, which > is calculated using the D=3 gravitational constant, G, should actually > be calculated using gravitational constant assuming D space dimensions > (i.e., if we wrote the force of gravity as F = G(D) * M * m / r ** > (D-1) in D dimensions) . I'm assuming that the gravitational > constant will reflect gravity's strength and thus be larger in D > dimensions than the value of G in 3 dimensions (Newton's gravitational > constant) If so, is there any way to speculate how much larger one > might expect the Planck length to be relative to the value of > 1.6x10-35 m? Hi Ted, First of all, there is absolutely no experimental justification for Planck length. So it is not the fault of Newton's G as we measure it in our 3+1 dimensions. ;-) But your suspicions may be correct in the sense that G is not being applied correctly to derive the Planck length. Which are mine also. In fact, I suspect that some of the recent papers dealing with this are correct and that the so-called Planck scale is really closer to the TeV scale from our perspective. We may find out in the not too far future when the LHC at CERN has been operating for awhile. Here is a new paper that I like alot because it puts fermions and gauge bosons into the "bulk" instead of just gravitons. http://www.arxiv.org/abs/hep-ph/0505074 FrediFizzx http://www.vacuum-physics.com/QVC/qu...uum_charge.pdf or postscript http://www.vacuum-physics.com/QVC/qu...cuum_charge.ps http://www.vacuum-physics.com

## Planck length calculated assuming D > 3 dimensions - would it be larger?

Actually, does Newton inverse distance law follows from Einstein
Theory (Riemann Tensor based theory) for any dimension?

teds@intex.com ha escrito:

> I'm reading Lisa Randall's "Warped Passages" and just finished Green's
> "Fabric of the Cosmos". In both, they mention that it seems unusual
> that gravity is so weak compared to the 3 other forces. One
> speculative resolution is that there are in fact D dimensions (D = 10
> or 11) and since we live in 3 space dimensions, we feel only part of
> gravity's full strength and that's why gravity seems so weak.
>
> That lead me to wonder whether the Planck length distance scale, which
> is calculated using the D=3 gravitational constant, G, should actually
> be calculated using gravitational constant assuming D space dimensions
> (i.e., if we wrote the force of gravity as F = G(D) * M * m / r **
> (D-1) in D dimensions) . I'm assuming that the gravitational constant
> will reflect gravity's strength and thus be larger in D dimensions than
> the value of G in 3 dimensions (Newton's gravitational constant) If
> so, is there any way to speculate how much larger one might expect the
> Planck length to be relative to the value of 1.6x10-35 m?
>
> Thanks,
>
> Ted

 arivero@unizar.es wrote: > Actually, does Newton inverse distance law follows from Einstein > Theory (Riemann Tensor based theory) for any dimension? No. In particular, not in 2-d, since the vanishing of the Einstein tensor (and hence the Ricci tensor) implies that the Riemann tensor is zero.

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