Is it a fact that vacuum energy exists?

Click For Summary

Discussion Overview

The discussion centers on the existence of vacuum energy and zero point energy, exploring whether these concepts are established facts in physics or if their existence remains uncertain. Participants examine theoretical implications, experimental evidence, and differing interpretations within the context of quantum mechanics and cosmology.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants assert that vacuum energy and zero point energy are established facts supported by observations, while others challenge this view, suggesting that evidence is not conclusive and that alternative explanations exist.
  • One participant highlights that the absolute energy level associated with the ground state is arbitrary, emphasizing that observable quantities are energy differences, particularly in the context of the Casimir effect.
  • Another participant argues that the Casimir effect should not be conflated with vacuum energy, suggesting that it can be explained through van der Waals forces instead.
  • Several participants reference the importance of peer-reviewed papers and textbooks over informal comments in discussions, indicating a preference for more rigorous sources of information.
  • There are claims that virtual particles are a necessary component of quantum field theory (QFT) and that they cannot be disregarded, although some participants express skepticism about their implications.
  • Confusion arises regarding the treatment of vacuum energy as a mathematical concept versus a physical reality, with participants questioning why many physicists consider it real despite arguments suggesting it is merely a mathematical artifact.
  • The cosmological constant is mentioned as an observed parameter often associated with vacuum energy, leading to questions about its implications for the reality of vacuum energy.

Areas of Agreement / Disagreement

Participants exhibit significant disagreement regarding the existence and interpretation of vacuum energy and zero point energy. Multiple competing views are presented, with no clear consensus reached on the matter.

Contextual Notes

Participants express uncertainty about the definitions and implications of vacuum energy and zero point energy, highlighting the complexity of the topic and the potential for differing interpretations within the physics community.

  • #31
anuttarasammyak said:
Say Casimir effect comes from energy differences of "vacuum energy", anyway Casimir effect has something to do with vacuum energy, doesn't it ?
No, because as I said the Casimir effect relates to "energy differences", not to "vacuum energy differences". There is an effective potential energy as a function of the distance ##d## between the plates, leading to an effective force, that's the main point. But taking the Casimir effect as "proof" for the existence of a vacuum energy (as e.g. hinted at in Weinberg's paper just cited) is plainly wrong.

In my opinion the only thing that is safe to say is that the relation between the cosmological constant and potential quantum effects is unclear.
 
Last edited:
  • Like
Likes   Reactions: protonsarecool and anuttarasammyak
Physics news on Phys.org
  • #32
otennert said:
In my opinion the only thing that is safe to say is that the relation between the cosmological constant and potential quantum effects is unclear.
Does that mean that it is unclear to say that the cosmological constant is the same as vacuum energy?
 
  • #33
Suekdccia said:
Does that mean that it is unclear to say that the cosmological constant is the same as vacuum energy?
Well, this is why it is called the "cosmological constant problem", isn't it? Again, I am referring to the Weinberg review from 1989. There are also tons of more recent literature on this.

Actually I think the Wikipedia entry is also a good entry point into this matter: https://en.wikipedia.org/wiki/Cosmological_constant_problem
 
Last edited:
  • #34
otennert said:
No, because as I said the Casimir effect relates to "energy differences", not to "vacuum energy differences". There is an effective potential energy as a function of the distance ##d## between the plates, leading to an effective force, that's the main point. But taking the Casimir effect as "proof" for the existence of a vacuum energy (as e.g. hinted at in Weinberg's paper just cited) is plainly wrong.

In my opinion the only thing that is safe to say is that the relation between the cosmological constant and potential quantum effects is unclear.
Thanks. I found a web article to explain it with a key word of "field radiation pressure".
"At a cavity-resonance frequency the radiation pressure inside the cavity is stronger than outside and the mirrors are therefore pushed apart. Out of resonance, in contrast, the radiation pressure inside the cavity is smaller than outside and the mirrors are drawn towards each other." https://physicsworld.com/a/the-casimir-effect-a-force-from-nothing/
 

Similar threads

  • · Replies 29 ·
Replies
29
Views
3K
  • · Replies 15 ·
Replies
15
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 10 ·
Replies
10
Views
3K
  • · Replies 27 ·
Replies
27
Views
4K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 75 ·
3
Replies
75
Views
12K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 15 ·
Replies
15
Views
2K