How Does the Cosmological Constant Λ Define the Cosmic Scale of Space-Time?

In summary, the equation which provides the invariant cosmological length-scale (while Planck length is the invariant quantum length-scale that replaces zero) is- L=\sqrt{\frac{1}{\Lambda}}For a cosmological constant of 1.252x10^-52 m^-2, this works out at 8.937x10^25 metres which equals 9.447x10^9 Lys (9.45 billion Lys).
  • #1
stevebd1
Insights Author
Gold Member
750
41
Apparently, one way to understand the effects of Λ on space-time is to apply the following equation which provides the invariant cosmological length-scale (while Planck length is the invariant quantum length-scale that replaces zero), length-scale being a measure of the space-time sheet-

[tex]\Lambda =\frac{1}{L^2}[/tex]

where L is 'the genuine physical meaning of the cosmological constant Λ, a maximal, impassable scale, invariant under dilations, that replaces infinity from the view point of its physical properties'.
Source- 'Scale-Relativistic Cosmology' by Laurent Nottale http://luth2.obspm.fr/~luthier/nottale/NewCosUniv.pdf

The equation can be re-written-

[tex]L=\sqrt{\frac{1}{\Lambda}}[/tex]

For a cosmological constant of 1.252x10^-52 m^-2, this works out at 8.937x10^25 metres which equals 9.447x10^9 Lys (9.45 billion Lys).

What is this length exactly? Is it suppose to relate to the cosmic light horizon (13.7 billion Lys) and 9.45 billion years is considered acceptable because it's within 1 order or is it a length in it's own right, and if this is considered the maximum length for a space-time sheet, what exactly becomes variable at this distance? If the Planck length is considered the quantum length-scale and anything smaller than this is quantum foam, what is supposed to happen at the cosmic length scale?

regards
Steve
 
Last edited by a moderator:
Space news on Phys.org
  • #2
On page six of the above paper, 'Scale-Relativistic Cosmology' by Laurent Nottale, the following statement appears-

'..This limit corresponds to the Planck length-time scale towards very small scales and to the cosmic scale IL toward very large scales. Therefore in the special scale-relativity framework, these two scales can neither be reached nor crossed (i.e. nothing actually exists beyond them), and they replace from the viewpoint of their physical properties respectively the zero and the infinite.' (page 6)

(the paper uses a figure of 1.362x10^-52 m^-2 for Λ giving a corresponding figure of ~9 billion light years for IL)

This idea of a space-time sheet having a maximum length of 9-10 billion light years seems to be at odds with the cosmic light horizon at 13.7 billion years and the corresponding comoving radius of 46.2 billion light years. Is it an alternative theory or something that works in conjunction with what we observe? Is it assumed that if 9-10 billion light years is the cosmic physical limit, light from objects outside this limit can still cross this boundary to reach use eventually? Would the cosmological length-scale be described as a radius or a length/diameter with us being in the middle of the space-time sheet?

Steve
 
Last edited:
  • #3
While there is plenty of evidence of the Planck scale (lP) being used in quantum and astrophysics, is there a significant use for the cosmic scale (IL) in equations other than IL [itex]=\sqrt{1/\Lambda}[/itex] or is it simply just 'a number'? Does curvature become significant at IL and should be taken into account when calculating distances, is there any other evidence that supports this cosmic scale of ~9 billion lightyears (say, in the CMB)?

Steve
 
Last edited:

Related to How Does the Cosmological Constant Λ Define the Cosmic Scale of Space-Time?

1. What is Lambda as a unit of length?

Lambda, represented by the symbol λ, is a unit of length that is commonly used in physics and engineering. It is equal to one billionth of a meter, or 10^-9 meters.

2. How is Lambda related to light and electromagnetic radiation?

Lambda is often used to measure the wavelength of light and other forms of electromagnetic radiation. It represents the distance between two consecutive peaks or troughs in a wave.

3. Can Lambda be used to measure other types of waves?

Yes, Lambda can be used to measure the wavelength of any type of wave, including sound waves, water waves, and seismic waves.

4. What is the significance of Lambda in quantum mechanics?

In quantum mechanics, Lambda is used to represent the de Broglie wavelength of a particle. This is the wavelength associated with a particle's momentum and is an important concept in understanding the behavior of particles at the quantum level.

5. How is Lambda different from other units of length?

One key difference is that Lambda is a very small unit of length, while other units like meters or kilometers are much larger. Additionally, Lambda is often used in the context of waves and particles, while other units are used for more everyday measurements.

Similar threads

  • Cosmology
Replies
4
Views
2K
Replies
1
Views
1K
Replies
7
Views
2K
  • Beyond the Standard Models
Replies
1
Views
1K
Replies
29
Views
7K
Replies
5
Views
3K
  • Special and General Relativity
Replies
7
Views
2K
  • Cosmology
Replies
1
Views
2K
  • Beyond the Standard Models
Replies
31
Views
6K
Replies
2
Views
4K
Back
Top