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Physicists Predict a Way To Squeeze Light From the Vacuum of Empty Space (sciencemag.org)
sciencehabit shares an excerpt from Science Magazine: Talk about getting something for nothing. Physicists predict that just by shooting charged particles through an electromagnetic field, it should be possible to generate light from the empty vacuum. In principle, the effect could provide a new way to test the fundamental theory of electricity and magnetism, known as quantum electrodynamics, the most precise theory in all of science. In practice, spotting the effect would require lasers and particle accelerators far more powerful than any that exist now. Physicists have long known that energetic charged particles can radiate light when they zip through a transparent medium such as water or a gas. In the medium, light travels slower than it does in empty space, allowing a particle such as an electron or proton to potentially fly faster than light. When that happens, the particle generates an electromagnetic shockwave, just as a supersonic jet creates a shockwave in air. But whereas the jet's shockwave creates a sonic boom, the electromagnetic shockwave creates light called Cherenkov radiation. That effect causes the water in the cores of nuclear reactors to glow blue, and it's been used to make particle detectors.
However, it should be possible to ditch the material and produce Cherenkov light straight from the vacuum, predict Dino Jaroszynski, a physicist at the University of Strathclyde in Glasgow, U.K., and colleagues. The trick is to shoot the particles through an extremely intense electromagnetic field instead. According to quantum theory, the vacuum roils with particle-antiparticle pairs flitting in and out of existence too quickly to observe directly. The application of a strong electromagnetic field can polarize those pairs, however, pushing positive and negative particles in opposite directions. Passing photons then interact with the not-quite-there pairs so that the polarized vacuum acts a bit like a transparent medium in which light travels slightly slower than in an ordinary vacuum, Jaroszynski and colleagues calculate. Putting two and two together, an energetic charged particle passing through a sufficiently strong electromagnetic field should produce Cherenkov radiation, the team reports in a paper in press at Physical Review Letters. Others had suggested vacuum Cherenkov radiation should exist in certain situations, but the new work takes a more fundamental and all-encompassing approach, says Adam Noble, a physicist at Strathclyde.
However, it should be possible to ditch the material and produce Cherenkov light straight from the vacuum, predict Dino Jaroszynski, a physicist at the University of Strathclyde in Glasgow, U.K., and colleagues. The trick is to shoot the particles through an extremely intense electromagnetic field instead. According to quantum theory, the vacuum roils with particle-antiparticle pairs flitting in and out of existence too quickly to observe directly. The application of a strong electromagnetic field can polarize those pairs, however, pushing positive and negative particles in opposite directions. Passing photons then interact with the not-quite-there pairs so that the polarized vacuum acts a bit like a transparent medium in which light travels slightly slower than in an ordinary vacuum, Jaroszynski and colleagues calculate. Putting two and two together, an energetic charged particle passing through a sufficiently strong electromagnetic field should produce Cherenkov radiation, the team reports in a paper in press at Physical Review Letters. Others had suggested vacuum Cherenkov radiation should exist in certain situations, but the new work takes a more fundamental and all-encompassing approach, says Adam Noble, a physicist at Strathclyde.
Don't all vacuums have lights these days?
Except the cordless handhelds of course
This is beyond my function.
Everything above is my opinion....YMMV
Counting down to the first post on the lines of " ... blah blah scientists always claim stuff will be ready 'soon'. Wake me up when I can buy it on Amazon at a decent price ... whine grumble it's dark here in the basement ..." B^>
3 ... 2 ... 1 ...
Rgds
Damon
http://m.earth.org.uk/
(Or not. Shame about the energy levels involved, and all that... But then again - that's an engineering problem...)
The energy is squeezed from the other, higher energy photons or from the parallel particle beams being set up. There is no "zero point energy" or "vacuum energy" being harvested here. It is the _lack_ of Cerenkov radiation from "particles" like photons that early on led to quantum physics.
How many billions are we supposed to spend now on pursuing this essentially worthless piece of knowledge?
E Proelio Veritas.
It is meaningless but it sounds meaningful and cool.
... won't it be the case that the vacuum will be even darker than before ?
But then, they will make it even harder to detect dark matter against this very dark vacuous background of space.
...somebody will put a tax on the light coming from vacuum.
..continue to learn things and think they discovered them. This is called an "undulator" and it's a key component in free electron LASERs. It works, it's not something for nothing.
Let there be light!?
We should be careful playing around with this should it become more than a mere prediction.
CUR ALLOC 20195.....5804M
I wonder how they measure the precise-ness of a theory? What's the second-most precise theory in science? What's the least precise?
I wonder, if Hawking & Unruh Radiation are generated from quantum vacuum, using similar mechanism(s)?
ahhhhgg my pet peeve is when physicists confuse physics and math. This is a great example of this. They see something unexpected in a simple approximation of the math, and think wow that's magic!
Here's the general pattern of stupidity. First they create a mathematical model of an isolated system. Say atomic orbitals on an atom. They do this for a second atom. Noting in this representation says they atoms should "stick together". But surprise, they do and form a "covalent" or "ionic" bond.
Next what they do is they keep the original representation of orbitals -- cause that's math they can solve. And they perturb it a bit with a coupling term. Now they get some new energy levels which explain the bonding attraction.
Where they get confused is they keep descibing the system in the old orbitals but then talk about the new physics using the old terms.
In realitiy if you move beyond the perturbative treatment -- the one the maths can be solved for-- and move to just the full eigen states of the joined system you would not see any surprises at all. It's only a surprise when you don't do this.
Now there's absolutely nothing wrong with using perturbations on solvable systems rather than trying to do things exactly but on impractically harge to solve systems. Even better the perturbations give us some intuition about how the transiation from uncoupled to fully coupled happens. So I'm not knocking that.
I'm knocking the magical mysticism that comes from not realizing what the right math was and the right eigen states were.
In this case the if you overdrive space, then the eigne states of space are not the same as the ones they are descibing. they are emitting light because their over driving of the space creates a photonic state coupled to the matter states. they are literally making the photon not squeezing it out of the vaccum. those vacuum states don't even exist at all anymore in the he highly perturbed environment.
Here's a super tangible analogy. try balancing a broom stick upside down in the palm of your hand. it falls over because that's not an eigen state. Now move your hand rapidly in a circle. wow magically the the broom stays up. But what happened in math ville is not magic. the inverted state is an eigen state of this system.
Now this relates to this case as follows. Imagine instead of a broom we has electrons orbiting an atom. If we excite this with the right size photon the electron goes up an orbital then emits a different (or the same) photon when it relaxes back to a new unoccupied orbital. But suppose we hit this with a photon whose energy is above the ionization threshold. the electron gets blasted off. this is our broom falling over. Then we go into the lab and we try this and we find that strangely, the electron doesn't get blasted off. the photon is absorbed by the atom just like there was a resonant state there. But we know from the orbital model that isn't true. so it's magic! How did it happen. Well, if the electric field of the photon is large enough. and largre enough means it's on the same strength as the electric field between the electron and th enucleous then the photon's electic field is not a perturbation on the orbit causing electic field.
The mystical physcist descibes this as saying the photon figuratively creates it's own orbital on demand then occupies it. The mathematical phyicist says there is no atom and photon. there's an electromagnetic field. and this is an eigen state of that were the electron has some new wild orbital. It's exactly the same as the upside down broom. The rotation of your palm is the field of that photon perturbing the gravitaitonal field that makes the broom fall. And thus creates a new non-falling broom state.
there is no vaccum field in this perturbed system. It's just you exciting mater to make photons.
Some drink at the fountain of knowledge. Others just gargle.
You have a dipole oscillating in a resonance slot...cancelling it out. You add an oscillating component in the direction of travel and bingo.... photon. You only put in energy so you think photons are only energy...even the oscillation.
Here they're describing the same effect wrapped in some Scrodinger twaddle... but its really a step in the right direction IMHO.
From TFS:
Talk about getting something for nothing . Physicists predict that just by shooting charged particles through ...
"Shooting," and, "charged," suggests expenditures of energy.
That's not "nothing."
Thank you, thermodynamics.
It little behooves the best of us to comment on the rest of us.
... precise theory ...
Oxymoron much?
It little behooves the best of us to comment on the rest of us.
There you go: https://en.wikipedia.org/wiki/...
Video of some good progressive thrash music
Isn't a vacuum, by definition, void of all matter and at zero pressure? Or do a large majority of scientests beleave otherwise?
I'm a consultant - I convert gibberish into cash-flow.
Squeezing energy out of null-space-- isn't that a ZPM?