Physicists Predict a Way To Squeeze Light From the Vacuum of Empty Space (sciencemag.org) 82
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.
Light from a vacuum (Score:5, Funny)
Don't all vacuums have lights these days?
Except the cordless handhelds of course
Comment removed (Score:4, Funny)
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Only Buy Genuine Shop-Vacs(tm) From Approved Retailers!
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My cordless handheld has a light that comes on when I'm recharging it.
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A "vacuum cleaner" doesn't clean a vacuum; it cleans other things using a vacuum. it works by creating a partial vacuum that causes the atmosphere to push air across the brush head into the chamber, carrying dirt along with the air.
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Whoosh
That's what the vacuum cleaner said.
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Too stupid (Score:1)
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Someone invented a really inefficient way to generate light with magnets.
No you are not too stupid this is nonsense (Score:2, Troll)
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 th
This is progress (Score:1)
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.
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They are describing a real effect first noticed for what is called cherenkov radiation (google that term to learn the details). What it means is that in an optically dense media or equivalently any slow waveguide, light travels slower than c, the speed in free space. In such a medium, you can shoot a particle like an electron faster than the slowed down light. This results in weird radiation effects. It's not too hard to make the light slow. it's basically c/index-of-refraction. so for example glass h
Can't buy it on Amazon yet (Score:2)
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
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It is meaningless but it sounds meaningful and cool.
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... precise theory ...
Oxymoron much?
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There you go: https://en.wikipedia.org/wiki/... [wikipedia.org]
So... Star Wars-type holograms soon, then? (Score:1)
The photons are not "squeezed from the vacuum" (Score:2)
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.
Sounds interesting (Score:2)
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You could probably fund the Future Circular Collider, ITER and its successor, a new ISS, and every proposed physics experiment and mars lander for something like the F35 program. Which do you think is a better investment for society?
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It's people like you, stuck in the mindset of WWII, who are accepting old solutions to a new weaponscape. For instance, tanks are obso- fucking -lete.
Fighter jets are great as bombers but who in simple hell is getting into dogfights these days?
Think of drones, autonomous bombers operated from an office in NYC by a pimple-faced kid hired by contractor Booz Allen Hamilton.
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TBH, it is hard to predict what warfare would be like today between wealthy nations that have attackable logistics. For that matter, drones have not really proven themselves in actual war, only in the 'rich country shooting at poor country
Re:Sounds interesting (Score:4, Interesting)
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Thanks for posting something relevant.
My BIL works for Lockheed-Martin and a couple of years ago while he was working in Israel, he posted to his Facebook, the press release that LM had just shipped the umpty-umpth F35.
That very afternoon, the F35 was the subject of a scandalous documentary of overspending, defective product, with pilots saying they wouldn't fly it and that, in the years of delay, other countries had implemented newer technology.
He took the post down immediately.
If they squeeze the light out of the vacuum ... (Score:3)
... 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.
I know what will happen... (Score:2)
Millennials... (Score:1)
So... (Score:2)
Let there be light!?
We should be careful playing around with this should it become more than a mere prediction.
"most precise theory" (Score:2)
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?
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The calculate the results of an interaction, and then they measure it. So far, we've got a ton of these prediction/experiment couples accurate to better than one part in a billion, and at least one that is better than one part in a trillion.
Feynman once said that it was like measuring the distance between New York and Los Angeles accurately to within the width of a human hair.
General relativity, for comparison, is accurate to about one part in 500 (orbit of Mercury), or one part in 5000 (Cassini). GR is m
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Er well, yeah, but that's the precise-ness of our ability to measure, not the precise-ness of the theory itself. If we were able to measure GR effects to 1 part in a quadrillion, nothing about the theory itself would have changed -- only our ability to measure things. Eh, it don't matter. It just struck me as an odd way to refer to a characteristic of a theory.
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That's not entirely true. There's error in our measurement, yes, but there's also error in the theoretical prediction.
Most modern theories require some approximation. QED, for example, posits that any particle interaction will be affected by an essentially infinite sum of contributions. Since these contributions become smaller and smaller, you can add up the first few and get a pretty good prediction... but not perfect.
Still, instead of "most precise theory" a better description might be "most precisely v
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Mod this up.
I posted essentially the same. "Laws," of physics have a preciseness that we're continually fine-tuning.
Theories are scientific wild-ass guesses.
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Eeek that's not what I meant. Mostly I was saying that when we say "E equals MC squared", it's a strict mathematical equivalence, and it has no need for a measure of precise-ness. But from now on, I'm going to say "E equals MC squared, give or take" just for funsies.
A Mechanism for Hawking & Unruh Radiation? (Score:1)
I wonder, if Hawking & Unruh Radiation are generated from quantum vacuum, using similar mechanism(s)?
Something for nothing ... (Score:2)
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.
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Empty vacuum? (Score:2)
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In quantum mechanics a vacuum is defined as the lowest possible energy state. The uncertainty principle prohibits zero energy states, so a vacuum always has some base energy, which can be thought of as a sea of virtual particles popping into and out of existence.
Space that includes a strong magnetic field and particles zipping through it isn't really a vacuum, but I think the point of the calculation is that the virtual particles in an actual vacuum can be polarized a little bit by a strong magnetic field a
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Yes. In ways they couldn't imagine.
Also, the much maligned aether, a substance that permeates all of space and (a bit later, the medium through which light propagates), is basically how you'd describe quantum fields (from the standard model) and space-time (from relativity).
Comment (Score:2)
Squeezing energy out of null-space-- isn't that a ZPM?