 |
 |
Vacuum Energy and Universe Expansion
Name: George
Status: student
Age: N/A
Location: N/A
Country: N/A
Date: N/A
Question:
This question is essentially about the nature of "vacuum
energy." If virtual particles pop in and out of existence based on the rules
of quantum uncertainty, why is not the energy of the vacuum being
progressively depleted given that space is expanding and the conservation
laws say that energy cannot be created? I would like to add that I
understand virtual particles mutually annihilate so the net energy balance
remains zero, in the vicinity of a black hole, one such particle can be
absorbed and another set loose outside the event horizon, therefore,
creation ex-nihilo?
Replies:
Hi George,
I sense a little confusion in the question you're asking, so maybe
restating your question might help. If I understand you, it sounds
like you are asking "if the universe is expanding and the total energy
in the universe is constant, then is the average energy density of the
universe declining?" --- which when stated that way, the answer would
be yes for macroscopic systems. When you consider very small systems
(where quantum effects dominate), it is a little harder to define
boundaries, but the law of conservation of energy still applies. I am
oversimplifying a bit here, so let me know if you are asking about a
specific detail regarding quantum/relativistic details.
Hope this helps,
Burr Zimmerman
Click here to return to the Physics Archives
| |
Update: June 2012
|
|
