Linked Questions

6
votes
1answer
3k views

Confusion in understanding of quantum fluctuations and vacuum energy [duplicate]

I'm having a bit of trouble understanding what exactly is meant by a quantum fluctuation of a quantum field and its relation to the vacuum energy attributed to such a field. Is the point, that due ...
1
vote
3answers
2k views

Is the empty space really empty? [duplicate]

I've come across another article in "list verse" which says that the empty space is not actually empty at least for a while. I've tried to find about this, so I googled it .It also quotes a word "...
-1
votes
1answer
610 views

Universe from nothing? [duplicate]

I just finished the book of Lawrence Krauss "Universe from nothing" and he said that virtual particle can pop to existance from nothing by quantum fluctuations of the field from the vacuum and in the ...
2
votes
4answers
208 views

QFT and vacuum energy [duplicate]

According to Quantum Field Theory, all 'particles' are oscillations in their own fields. And according to Vacuum Zero Point Energy and the Heisenberg Uncertainty Principle, these fields have ...
0
votes
0answers
91 views

Fluctuations in the value of a quantum field at a point? [duplicate]

Suppose there’s a scalar field that permeates the universe. Do quantum fluctuations really cause the field value ϕ to fluctuate, making the field value higher at some points in space and lower at ...
0
votes
2answers
41 views

Virtual particles, conservation of energy & the fabric of space [duplicate]

Do virtual particles take energy from the fabric space and when they annihilate in the split second they distribute that energy back to space, therefore abiding by the law for the conservation of ...
1
vote
0answers
73 views

How do quantum fluctuations make up vacuum energy? [duplicate]

Quantum fluctuations are thought to be the reason why we have energy even if there is nothing in a region of space. My question is if quantum fluctuations give back what they got from nothing using ...
0
votes
0answers
64 views

Virtual pair of particle-antiparticles trajectory [duplicate]

Is it possible to do heuristic calculations on virtual pair of particle-antiparticle trajectories that appear in a vacuum? For example, what is the maximum distance between them during virtual process?...
0
votes
0answers
60 views

The fundamental transition problem [duplicate]

can anyone explain what is mentioned here https://arxiv.org/abs/1405.6091 (page 7 and 8) in simple terms: Finally, Krauss makes the very problematic claim that “the structures we can see, like ...
16
votes
2answers
2k views

Virtual particles and physical laws

Recently, I was reading about Hawking Radiation in A Brief History of Time. It says that at no point can all the fields be zero and so there's nothing like empty space(quantum fluctuation etc.). Now, ...
6
votes
5answers
10k views

What is meant by “Nothing” in Physics/Quantum Physics?

I am not a phycisist, so please forgive my ignorance. This is related to my posts and this. I am trying to understand what is meant by the term "Nothing" in physics or Quantum Field Theory (QFT) since ...
16
votes
3answers
1k views

Why isn't the De-Broglie wavelength of massive particles redshifted in an expanding universe

It is pretty straight forward how light is redshifted in an expanding universe, yet I still can't understand why the De'Broglie wavelength of a massive particle isn't redshifted in an expanding ...
11
votes
4answers
581 views

Is the term “quantum fluctuation” an aide to understanding? [closed]

I would like to ask if anyone has found a tight enough way to define the term "quantum fluctuation" so that it can become a useful rather than a misleading piece of physics terminology. Terminology ...
5
votes
1answer
664 views

Virtual particle density in an expanding Universe

As the universe continues to accelerate in its expansion, does the virtual particle density decrease or remain the same throughout spacetime?
0
votes
2answers
642 views

Shimmering from heated air and the speed of light

A few months back, I was using binoculars to check if my friend was on his boat, which was around 2 to 3 km out to sea from the shoreline where I was standing. The images from, say the sail of the ...

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