UHFF stands for Ultra-High Field Facility. The project is at times confused with the Extreme Light Infrastructure (ELI), which includes three other experiments apart from UHFF. The total bill is $1.6 billion Euros (as of now).
ELI Hungary – one of four locations in the total ELI project.
According to various sources, UHFF will probably be located in the UK somewhere in 2020, earliest 2017. Ten lasers will concentrate 200 petawatts of power, the equivalent of 100 thousand times the world's electric power output, into “a single point for a trillionth of a second”.
Homework for science writers: Given the velocity of light and “trillions of a second”, actually they mean an attosecond, or in scientific notation 10-18 seconds, how many hours do you need to figure the length of “a single point”? Well let me help: 10-18 seconds times a few 108 meters per second equals a few 10-10 meters, which is a few atoms across. Certainly not “a single point”: this length is enormously bigger than the tiny length scales that matter in fundamental particle physics. So, what is UHFF supposed to do that is so awesome?
As with the LHC and similar endeavors, “super fundamental physics” hype is created to justify the price tag. UHFF may find dark matter, which is the same empty promise as with the LHC. Since we do not know much about dark matter, dark matter may pop up anywhere unexpectedly for all we know.
“We may accidentally destroy the universe” hype is heaped on top of finding all the holy grails. The LHC was sold as making black holes as well as recreating the big bang. And the UHFF? Ed Gerstner, senior editor on Nature Physics:
“Physicists are planning lasers powerful enough to rip apart the fabric of space and time.” Laser physics: Extreme light
People understandably become worried about making the vacuum unstable in our backyard. People do not like their world being destroyed, but the creation of panic and corrosion of public trust in science is collateral damage.
Are independent media mediating that hype?“scientists claim it could allow them boil the very fabric of space ... pulling this vacuum "fabric" apart.” Science News Telegraph
What about the science blogs that are supposedly better than traditional media:
“they want to build a laser so powerful that it will literally rip spacetime apart ...by giving spacetime a hernia, it is hoped that theorized "ghost particles" may spill from the fissure, providing evidence for the hypothesis that extra-dimensions exist and the vacuum of space isn't a vacuum at all -- it is in fact buzzing with virtual particles ... this immense energy will punch a hole through the fabric of spacetime itself” Discovery blog
So, here we go again. Apart from empty promises, they start telling people that we open portals to other dimensions, and again it is not “the media”, but the science media and scientists themselves!
Luckily, none of these claims have anything to do with reality. What is UHFF actually supposed to do? I have not found a single source yet that would spell it out to the wider public in sober ways, so let me do what all those media claim to do and actually inform you soberly:
ELI-UHFF will try to explore high electric field strengths to hopefully see something that can be interpreted as traces of mechanisms which theory predicts for fields which ELI will not get anywhere close to.
Sock-Puppet: “That is it?”
Yep
Sock-puppet: “No collapse of space-time?”
No, sorry, not with some light.
Sock-Puppet: “But that mysterious mechanism is ultra important new stuff and can only be done by ELI, correct?”
The mechanism in question is electron-positron pair creation, which should happen at the so called Schwinger limit named after Julian Schwinger. That limit is 8 times 1018 Volt per meter, which needs light intensities exceeding 1030 Watt per cm2 and is unattainable by ELI’s mere 10²³ Watt per cm². Electron-positron pair creation is well known from particle accelerators where these high fields turn up implicitly in the reactions triggered by particle collisions. HiPER, the High Power laser Energy Research facility dedicated to laser driven fusion, promised the exact same thing.
HiPER
Sock-Puppet: “So you are anti science and say that ELI should not be funded by the tax payer and we should read the bible instead?”
The facility is comparatively cheap and should be build. But why the science distorting hype? What annoys is the distortion of science – again, by scientists with no bad Oil company manipulating the media being involved!
Professor Wolfgang Sandner, coordinator of the Laserlab Europe network and president of the German Physics Society:“even a true vacuum is filled with pairs of molecules that come into our universe for an extremely short time. ... An extremely powerful laser should be able to pull these particles apart and keep them in existence for longer.” Source
This is actually nonsense, but media and scientists support it with more nonsense:
“In the 1970s, Stephen Hawking predicted that when a virtual particle–antiparticle pair is created just 'outside' a black hole, the warping of the local vacuum by the hole's gravity will be strong enough to tear the pair asunder,” Nature
“As predicted by Stephen Hawking, black hole evaporation is caused by virtual particles. Right at a black hole's event horizon -- the point at which even light cannot escape the extreme gravitational warping of the black hole -- virtual particles will pop in and out of existence as normal.
However, one of the pair of virtual particles may get sucked into the event horizon while the other is ejected. With no partner to annihilate with, the ejected particle keeps the borrowed energy all for itself, and becomes a real particle.
As this newly-real particle is ejected, it is effectively stealing energy (and therefore a tiny bit of mass) from the black hole -- this effect is known as Hawking radiation.” discovery blog
Interesting, isn’t it? Only problem: General relativity tells us that there is no “extreme gravitational warping” at the event horizon of a black hole! On the contrary, you do not notice anything at all for hours after falling into a sufficiently big black hole. All physics will be unremarkable and normal. If there is something like particle pairs that “pop in and out of existence as normal”, they will do the exact same in your rocket ship that falls into the black hole, namely pop in and out (!) of “existence” (whatever “existence” means in case of on principle unobservable theoretical entities).
An electron-positron pair that is at rest relative to the horizon (and therefore cannot be considered to be at rest in any rocket ship) would have to travel with light velocity. Anybody see a problem?
Hawking radiation does indeed have virtual particles in its mathematical description, which is a semi-classical calculation, so we know it is gets the correct result via an in a sense wrong approach (of which we happen to know when results are still reliable). These are intuitive interpretations which ease dealing with theoretical tools.
Virtual particle pairs are ripped apart by a gravitational field which does not even exist in the better (not semi-classical) description??? Well, be glad about the particles being virtual, which basically means that they do not "exist" either. If two non-existing entities interact, all is well in the world of science outreach.
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