Lee Smolin tantalizing hint in TTWT

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Discussion Overview

The discussion revolves around Lee Smolin's references in his book 'The Trouble With Physics', particularly a section that connects large-scale (general relativity) and small-scale (quantum mechanics) concepts through the distance scale (Rd) and mass scale (Rm) of the universe. Participants are trying to understand the implications of these scales and the fundamental constants involved.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Marcus questions which fundamental constants Smolin used to derive Rm from Rd, expressing confusion over the lack of clarity in the text.
  • Some participants attempt to calculate the mass corresponding to the distance scale but find the results to be unexpectedly small, indicating a potential misunderstanding or missing information.
  • One participant suggests that the relationship between length and energy in quantum mechanics might be relevant, noting the reciprocal nature of wavelength and energy.
  • Another participant proposes a method to estimate the mass scales of neutrinos based on their energy values, but struggles to relate these scales to Rm effectively.
  • There is a suggestion that the relationship between different multipole moments in cosmic measurements (from WMAP) might provide insight into the correlation between Rd and Rm.

Areas of Agreement / Disagreement

Participants express uncertainty and confusion regarding the calculations and interpretations of Smolin's work. There is no consensus on the meaning of Rm or the specific constants involved, and multiple competing views on how to approach the problem remain.

Contextual Notes

Participants note limitations in their understanding of the relationships between the scales and the constants, as well as the precision of neutrino mass measurements. There is an acknowledgment of potential ambiguities in the definitions used in the discussion.

RandallB
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Lee Smolin tantalizing hint in TTWP

Marcus
You seem to have one of the best reads on Lee Smolin and the points he makes.
I’m hoping you, or someone here, can help make sense of part of his book ‘The Trouble With Physics’.
On page 217 he refers to “another tantalizing hint”, relating the very large (GR scale) with the very small (QM scale).
He is dealing with Rd the distance scale and Rm the mass scale of the universe (my subscripts on R).
I understand arriving at 10^60 of Planck scale for Rd (page 204).
Lee then uses “just the fundamental constants of physics” to covert that to Rm.

Which constants did he apply; and what is Rm?
It would have been simple enough to just list them in his book!

His point is Rm give the same “order of magnitude” as the mass differences between the different types of neutrinos.
What is he talking about?
He could have listed this as well if it is such an important comparison.
I make the mass scale difference between electron and muon neutrinos as 10^5
and between muon and tau neutrinos as 10^2.
Maybe he means the full range for a 10^7 scale, I cannot tell from the book.
He seems about one paragraph short of making himself clear.

Can you, or does anyone, have a reference that might make sense of this.
 
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Hi Randall,
I think I can help
No, it turns out I CANT help. I tried and got crazy numbers!

He must be using some way I don't know to get an energy (or mass) corresponding to a length.

====================
HERE IS WHAT I TRIED which didnt work out:
If one is working in Planck units, the distance he is talking about (prob. square root of reciprocal cosm. const) is 10^60 Planck length.

So the mass, again in Planck units, would be (I'll explain later) 10^-60 Planck mass.

But Planck mass is just under 22 micrograms. So the mass he is talking about (the mass equivalent of the cosmo distance scale) is 10^-60 of that, or about 22 x 10^-66 grams...or 22 x 10^-69 kilogram.

THIS IS TOO CRAZY SMALL. So I am missing something. Maybe someone else can explain.
============================

Here is what is going on in the approach I tried. If you look at fundamental constants like h, or h-bar, and c, you find that h-bar c is the product of any photon's (angular) wavelength times its energy
there is a locked in relation between vacuum wavelength and energy----they are reciprocals

so anytime you specify a length, you are simultaneously specifying an energy----and a big length corresp. to a small energy

there is often a little ambiguity because you don't know whether the author is talking h or h-bar.
In my experience they most often mean h-bar-----they think of it as somehow more fundamental
(and they secretly prefer to think of the "angular wavelength" of something which is the length of a full cycle divided by 2 pi)----
but that 2 pi ambiguity only involves some order-one indefiniteness so it does not have much affect on these order-of-magnitude discussions.
 
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think of the energy of a photon which has that huge wavelength----it has to be miniscule

this is giving funny answers, I have to check.

==================

LATER: I went and looked at that passage on page 217 that you were asking about. And I can't interpret it.
I will give it another try later, if nobody else shows up and straightens us out.
 
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Well you point me in a better direction for Rm
I had been thinking of a larger number like the total mass, your smaller number makes much better sense.
By taking a broad guesses at neutrino masses, since they are not measured very precisely yet anyway, I think I can define a reasonable Kilo-gram Mass Scale for each neutrino as follows:

Code:
[u]Neutrino          eV            Kg-mass     Kg-mass scale[/u]
 electron        1 eV         2x10^-36             ^-36 
  muon          100 KeV       2x10^-31             ^-31
   tau           10 MeV       2x10^-29             ^-29

Now relating those scales I still cannot do,
as you say the numbers seem to be crazy small for Rm.

But since this is related to measurements from WMAP
If we look at the Dipole, Quadra pole and Octa-pole;
Wouldn’t the Rl be getting progressively shorter for each.
Thus the Rm would be progressively larger.
Maybe something here is where he sees a correlation,
if not in direct scale values, maybe it the ratios of the two sets of three?
 
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