What is Fluctuation: Definition and 57 Discussions
In quantum physics, a quantum fluctuation (or vacuum state fluctuation or vacuum fluctuation) is the temporary random change in the amount of energy in a point in space, as prescribed by Werner Heisenberg's uncertainty principle. They are tiny random fluctuations in the values of the fields which represent elementary particles, such as electric and magnetic fields which represent the electromagnetic force carried by photons, W and Z fields which carry the weak force, and gluon fields which carry the strong force. Vacuum fluctuations appear as virtual particles, which are always created in particle-antiparticle pairs. Since they are created spontaneously without a source of energy, vacuum fluctuations and virtual particles are said to violate the conservation of energy. This is theoretically allowable because the particles annihilate each other within a time limit determined by the uncertainty principle so they are not directly observable. The uncertainty principle states the uncertainty in energy and time can be related by
Δ
E
Δ
t
≥
1
2
ℏ
{\displaystyle \Delta E\,\Delta t\geq {\tfrac {1}{2}}\hbar ~}
, where 1/2ħ ≈ 5,27286×10−35 Js. This means that pairs of virtual particles with energy
Δ
E
{\displaystyle \Delta E}
and lifetime shorter than
Δ
t
{\displaystyle \Delta t}
are continually created and annihilated in empty space. Although the particles are not directly detectable, the cumulative effects of these particles are measurable. For example, without quantum fluctuations the "bare" mass and charge of elementary particles would be infinite; from renormalization theory the shielding effect of the cloud of virtual particles is responsible for the finite mass and charge of elementary particles. Another consequence is the Casimir effect. One of the first observations which was evidence for vacuum fluctuations was the Lamb shift in hydrogen. In July 2020 scientists report that they, for the first time, measured that quantum vacuum fluctuations can influence the motion of macroscopic, human-scale objects by measuring correlations below the standard quantum limit between the position/momentum uncertainty of the mirrors of LIGO and the photon number/phase uncertainty of light that they reflect.
I understand that vacuum fluctuations can spring into and out of
existence within a sufficiently short period of time, under the
uncertainty constraint.
However, I am currently a little confused over how this constraint is
applied.
1) Does one use del E.del t = h bar (the commutation...
Hi,
I'm doing more experiments with magnets and I'm making a setup to see if current can be induced in a coil by mechanically strengthening and weakening the pole of a permanent magnet. I can do this very simply by manually rotating a spinning disk with magnets on it close to the fixed magnet...
to preserve commutation relations in the quantized field operators (basically simple harmonic oscillator raising/lowering operators), a vacuum mode must be introduced in the case of a usual 50-50 beam splitter.
thus, one has 4 modes:
vacuum
incident mode
reflected mode
transmited...
hi i have fixed a simple circuit for lighting up a led.i have included a potentiometer. as the led is white i know that the voltage drop of the led is around 4v.when the potentiometer is at min resistance the voltege drop is actuallu around 3.8v.the problem is that when i turn the potentiometer...
I have a question. I decided not to put it in the "theory" section because I'm no physicist and I don't know if I'm right.
From what I understand about the fluctuation theorem, the smaller the area in which it takes place, the more likely entropy is to decrease. Could it be at the beginning...
[SOLVED] vacuum fluctuation
I have a few questions about this topic.
1. If their is build energy in vacuum (from Heisenberg's uncertainty principle), for example:
build: 10 J ==> here for: d(t)=h/(4pi)/10J
There must be built a particle and an anti particle
==> particle has 5 J and...
In quantum physics, a quantum fluctuation is the temporary change in the amount of energy in a point in space, arising from Werner Heisenberg's uncertainty principle." Quote from wikipidia".
can someone tell me what caused the first, "temporary change", i am
guessing that the first temporary...