

Scientists create light from vacuum - eande
http://www.physorg.com/news/2011-11-scientists-vacuum.html

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ars
What!?

This is just incorrect. They aren't creating light from vacuum - they are
simply creating light in _exactly_ the same way that antennas create light.

Antennas create light (electromagnetic energy) by vibrating electrons at the
same frequency of the light they want to create.

Here they are also vibrating electrons at the frequency of light. "several
billions of times a second" - frequency of microwaves? Ghz. Exactly the same.

Accelerating an electron (actually any charged particle) creates light. For
example: <http://en.wikipedia.org/wiki/Synchrotron_radiation> You can shake
the electron, force it to curve, anything and it will radiate light.

I've often thought that this would be an awesome way to make a laser if you
could find a material you can vibrate fast enough.

~~~
Sharlin
Umm, I'd like to give the scientists involved a benefit of the doubt. The
probability that they don't know what they're doing is much lower than the
probability that a popularized article about their study is incomplete and/or
inaccurate.

The actual paper is available at arxiv and is quite readable:
<http://arxiv.org/abs/1105.4714>

~~~
ars
Well the actual experiment was awesome - full credit for that.

I just don't buy that you need to explain it using virtual photons that bounce
of the mirror.

They do write:

"A mirror moving in a finite EM field then losses energy as the screening
currents will emit EM radiation, as in an antenna."

And then say you need vacuum fluctuations to explain it still happening
without an EM field. And explain it as the vacuum having a random EM field
that is acting on the mirror.

I guess that's not quite the same as "virtual photons bouncing on a mirror".
But since a charged mirror requires no extra field, and since their mirror
basically _is_ charge, I really don't see the need to bring in virtual photons
here.

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VladRussian
>What happens during the experiment is that the “mirror” transfers some of its
kinetic energy to virtual photons, which helps them to materialise.

how is that different from just saying that their vibrating EM field radiated
the energy (a vibrating EM field does radiates the energy and this radiation
is photons by definition) without bringing in "virtual photons"

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sp332
Is true that the energy put into the system (in the form of the dynamic
mirror) must be the same or greater than the energy of the photons taken out?
I don't think this is the "zero-point energy" or "reactionless engine"
breakthrough that people on that page are hoping it is.

~~~
srl
Yes. Bear in mind that each individual photons carries very little energy -
the energy required to generate the described 'mirror' is enormous by
comparison.

The main value of this is further experimental verification of certain aspects
of quantum physics, as mentioned at the bottom of the article.

~~~
ars
The energy is not in generating the mirror, but in shaking it. That energy is
directly used to create the photons.

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rsanchez1
And the scientists said, "Let there be light!" And there was light.

