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LHC Flips On Tomorrow
BTJunkie writes "The Large Hadron Collider, the worlds most expensive science experiment, is set to be turned on tomorrow. We've discussed this multiple times already. A small group of people believe our world will be sucked into extinction (some have even sent death threats). The majority of us, however, won't be losing any sleep tonight."
Reader WillRobinson notes that CERN researchers declared the final synchronization test a success and says, "The first attempt to circulate a beam in the LHC will be made this Wednesday, Sept. 10 at the injection energy of 450 GeV (0.45 TeV). The start up time will be between (9:00 to 18:00 Zurich Time) (2:00 to 10:00 CDT) with live webcasts provided at webcast.cern.ch."
I don't understand the whole "miniature black hole" thing. I think the naysayers have just been reading too much sci-fi. Microscopic black holes would evaporate in a very small amount of time due to Hawking radiation...they would leave a detectable energy signature so that we could tell they were there, but that's about it. The LHC won't be doing anything that isn't already happening in the upper atmosphere due to cosmic rays anyway.
They will be only sending a beam around the LHC in a single direction at about 7% power. It will be about a month before they send a beam in the other direction and have a collision. I think it is about a year before they will be up to full power.
Dr. Egon Spengler: There's something very important I forgot to tell you. Dr. Peter Venkman: What? Dr. Egon Spengler: Don't cross the streams. Dr. Peter Venkman: Why? Dr. Egon Spengler: It would be bad. Dr. Peter Venkman: I'm fuzzy on the whole good/bad thing. What do you mean, "bad"? Dr. Egon Spengler: Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light. Dr Ray Stantz: Total protonic reversal. Dr. Peter Venkman: Right. That's bad. Okay. All right. Important safety tip. Thanks, Egon.
No boom tomorrow either:
"First beam circulated" != "First collisions"
Also, beam will be circulated at injection energy (450GeV) and not accelerated to the design collision energy. Even if they did circulate beam in both directions *and collide them* (a separate activity) the total energy of collision would still be less that half of what the tevatron at Fermilab, USA, has been doing for many years. If *that* were a problem we'd already be
One of the main fearmongers concerning the LHC is Otto Rossler. He's a 68-year-old biochemist whose initial career was respected and conventional, but in recent years has veered into promoting his own "Theory of Everything" that contradicts the Theory of Relativity. According to Rossler, (a) Hawking radiation doesn't exist, and (b) microscopic black holes created by cosmic rays are moving so fast that they pass right through the earth, whereas LHC black holes will be trapped by earth's gravity and destroy the planet.
What's really happening is that Rossler and others like him are using the LHC as a soapbox to promote their particular brands of pseudoscience. From what I've read, any debate with Rossler quickly leads to him promoting his own pet theories, rather than any rational examination of the risks.
Doctors Karl Kruszelnicki and Kevin Varvell are giving an LHC lecture at the University of Sydney tonight. 7pm at the Footbridge Theatre. Varvell is a contributor to the ATLAS detector. Kruszelnicki is always fun. It includes a live cross to CERN. The lecture was to be in the school of Physics but has had to be transferred to a larger venue due to popular demand.
For some reason, the BBC are making a big thing of this, and providing a lot of coverage and related programmes on the Radio 4 station.
The BBC provide a listen again service for those of you who are distant but interested. Check out the programmes here:
http://www.bbc.co.uk/radio4/bigbang/
Assuming that the world isn't swallowed up by a black hole from the experiment, that is:
http://www.nytimes.com/2008/04/15/science/15risk.html
Open Source Drum Kit, LPLC deve board - mjhdesigns.com
The International Space Station gets that (dis)honor, with an estimated cost of $25.6B (US) from 1994 to 2005, not including shuttle costs - and that's just NASA's budget.
So, from that perspective, the LHC is a bargain. And it's probably still cheap compared to what the Superconducting SuperCollider would have ended up costing.
"Diplomacy is something you do until you find a rock." --Richard Pound
That's exactly what I was going to say. And I will also add:
"Collisions" != "Boom"
But I think I'll still be flagged as Redundant
Even if they don't evaporate, black holes don't produce a stronger gravitational field than other objects of the same mass. As long as the law of conservation of matter holds (or even if the amount of matter in the LHC triples) we should be fine.
wikipedia is wrong or was edited for hilarity. in the books, it's actually "big mistake of '38"
wikipedia is wrong or was edited for hilarity. in the books, it's actually "big mistake of '38"
Actually, I performed that edit, but it's the '38 that's wrong. I was just reading The Rise of Endymion last night, and it clearly says "Big Mistake of '08", page 92, near the bottom. And that's coming from the AI on the Consul's ship, so it ought to be reliable ;-)
Reality gets sucked into the void on my fuckin' birthday. ...
Oh well, it's been a nice 48 years. So long, & thanks for all the fish.
sig has been sent away for a few small repairs...
I didn't miss the joke -- I LOL'ed, I promise -- but speaking as a CERT instructor: you were told to get under your desks not to protect against a blast near enough to cause vaporization, but to protect against a possible collapse of a building damaged by an otherwise-non-lethal pressure wave. Yes of course if the bomb detonates right above you, you're toast, and if the bomb detonates far enough away that the pressure wave can't cause building damage then you're cowering under your desk for nothing. For the huge chunk of distance-from-ground-zero in between those two extremes, though, your chance of surviving a building collapse is much greater if you have a personal void to hide inside -- like the area under a desk. That's why your 'nuclear bomb drill' and your 'tornado drill' are so similar: you are increasing your odds of survival, being successfully located and extracted by search and rescue teams, in the event that part of your building collapses.
A counter to the argument that any subatomic black holes the LHC produces would behave differently than those produced in cosmic ray collisions in the upper atmosphere is the existence of neutron stars. Cosmic rays are constantly colliding with these objects as well.
Neutron stars present a gravity well surpassed only by that of black holes, so even subatomic black holes moving at relativistic velocities are likely to be pulled in. The densities of neutron stars are such that if it is indeed possible for a subatomic black hole to grow to macroscale by encountering nearby matter, there would be no place likelier. After billions of years of cosmic ray bombardment, one should expect at the very least to find lots of black holes with masses between the Chandrasehkar and Tolman-Oppenheimer-Volkoff limits (roughly, between 1.4 and 3.0 solar masses), implying that these events are the ultimate fate of neutron stars.
That is not what is observed however; there are in fact no known black holes with masses in that regime, while there are a lot of neutron stars. And it would take much longer than the current lifetime of the universe for a 2 solar mass black hole to evaporate by Hawking radiation, so if they were ever made, they should still be around.
So either subatomic black holes are not produced in energetic collisions of cosmic rays, which is good news because those energies are far greater than what the LHC will produce, or subatomic black holes very, very rarely or never survive to consume massive objects, which is also good news.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
Imagine a road that goes in a circle.
Now, tomorrow, they're going to put ONE CAR on the road
and drive it moderately fast to make sure the road is intact.
Then they will proceed, in future tests, to drive that ONE CAR
faster and faster around the circular road to make sure the road holds up.
On "collision day", the add a SECOND CAR driving in the
OPPOSITE DIRECTION on that circular road.
Then they drive those two cars REALLY REALLY FAST and crash them head-on
into each other.
The point is to try to understand the cars and how they are put together
by analyzing the parts that go flying off in the collision, and the speed
and direction that those parts went flying.
Nobody is in the tunnel while the beam is on, except cockroaches. Since the particles are moving in a circle they are as if accelerating constantly and consequently they as charged particles constantly give off radiation, in the gamma range somewhere. The whole tunnel is constantly bathed in lethal levels of radiation.
All rites reversed 2010
Has anyone here read about the "Oh-My-God particle"? A proton detected in 1991 with an energy of 3.2±0.9×10^20 eV - that's 51 Joules, an energy you'd expect for a macroscopic object and 10 million times more than the maximum the LHC can produce (7 Tev).
The linked page has some of the relativistic properties calculated for that proton including that "After traveling one light year, the particle would be only 0.15 femtoseconds -- 46 nanometres -- behind a photon that left at the same time."
Parent is correct: I have often considered making the same points whenever the whole "duck and cover" thing is discussed.
However, he leaves out the issues of flash and broken glass, which are even more likely to create a survivability opportunity over a wide radius than building collapse. Being under a desk is a simple rule of thumb for minimizing those injury modes.
Phew! I was worried that I overslept and missed the Strangelet singularity! Talk about stating the obvious.
Wikipedia: -1 Redundant
Dammit Otto, you have lupus.