Does the Uncertainty Principle imply a linear cosmology?

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SUMMARY

The discussion centers on the application of the Uncertainty Principle to cosmology, specifically regarding the age of the Universe and its implications for energy fluctuations. It is established that the relationship between energy uncertainty (ΔE) and time uncertainty (Δt) is defined by the equation ΔE Δt ∼ h. However, participants argue that applying the Uncertainty Principle to the Universe as a whole is flawed, as external measurements cannot be made. The conclusion emphasizes that the concept of "energy fluctuations" in the context of the entire Universe is incorrect.

PREREQUISITES
  • Understanding of the Heisenberg Uncertainty Principle (HUP)
  • Familiarity with cosmological concepts such as the scale factor a(t)
  • Knowledge of quantum field theory, particularly zero-point energy
  • Basic grasp of the relationship between energy and wavelength in quantum mechanics
NEXT STEPS
  • Research the implications of the Heisenberg Uncertainty Principle in quantum mechanics
  • Study the concept of the scale factor in cosmology and its mathematical representations
  • Examine the role of zero-point energy in quantum field theory
  • Explore the limitations of applying quantum principles to cosmological scales
USEFUL FOR

Physicists, cosmologists, and students of quantum mechanics who are interested in the intersection of quantum theory and cosmology, particularly those examining the implications of the Uncertainty Principle in a universal context.

jcap
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If the uncertainty in the age of the Universe is ##\Delta t## then the Uncertainty Principle implies that it has an uncertainty in its energy ##\Delta E## given by
$$\Delta E \ \Delta t \sim h.\tag{1}$$
If this energy fluctuation excites the zero-point electromagnetic field of the vacuum then a photon is created with energy ##\Delta E## and wavelength ##\lambda## given by
$$\Delta E \sim h \frac{c}{\lambda}.\tag{2}$$
Combining Equations ##(1)## and ##(2)## we find that
$$\lambda \sim c\ \Delta t.\tag{3}$$
Now as this characteristic length ##\lambda## is the wavelength of a photon it is a proper length that expands with the Universal scale factor ##a(t)## so that
$$\lambda \sim a(t).\tag{4}$$
Combining Equations ##(3)## and ##(4)##, and taking ##\Delta t \sim t##, we arrive at a unique linear cosmology with the normalized scale factor ##a## given by
$$a(t) = \frac{t}{t_0}.$$
where ##t_0## is the current age of the Universe.
 
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I'll leave it to more knowledgeable folks to weight in, but what I think is that you have extrapolated the HUP to WAY outside of it's domain of relevance.
 
jcap said:
If the uncertainty in the age of the Universe is ##\Delta t## then the Uncertainty Principle implies that it has an uncertainty in its energy

You can't apply the uncertainty principle to the universe as a whole since there is no way to make an external measurement on it, and the uncertainty principle applies to external measurements.

Also, there is no "energy-time" uncertainty principle as you are using it. See, for example, here:

http://math.ucr.edu/home/baez/uncertainty.html

So your post is based on at least two incorrect premises.
 
jcap said:
If this energy fluctuation excites the zero-point electromagnetic field of the vacuum

Correction, three incorrect premises. The universe as a whole doesn't have "energy fluctuations" in this sense.
 

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