CERN also has a particle decelerator – and it’s trying to break physics Sorry, new physics fans, CERN has once again failed to break the old physics, this time using a particle decelerator that chilled helium atoms close to absolute zero. The organisation is checking the mass of the proton's antimatter twin, the antiproton, using a specialised spectrograph. The measurement is an important test …
@ Mark 85 - Hmmn - might need to call it a kimarse or some such to avoid confusion with bottom quarks (quarks come in strange,charmed, up, down, top and bottom varieties. Top and Bottom used to be called Truth and Beauty, I've no idea why their names were changed though).
> Hmmn - might need to call it a kimarse or some such to avoid confusion with bottom quarks
No need for confusion, one would be a bottom quark while the other would be a bottom quirk. Naming them kimarses would lead to a linguist battle with the inevitable discoverers of the kimass.
As far as we know, according to The prophecy theory, if a person made of anti-matter inhaled a lungful of anti-helium, their voice should sound higher, like a person inhaling helium.
Although if they swapped balloons somehow, and a person inhaled anti-helium, all you'd get is a large bang as the particles annihilate each other.
Cool aside, if you inhale Sodium Hexafluoride gas you get "demon voice"- as shown here https://youtu.be/d-XbjFn3aqE
If it's the super-cooled stuff, then you've got more pressing things to worry about than your voice pitch, like your lungs and trachea freezing (even aside from any matter/anti-matter reactions between the anti-proton and normal ones).
Back in my PhD days people always used to wonder why I'd never tried inhaling the liquid Helium we used to work with, at least until I pointed out the temperatures involved.
"Can't say that I've ever inhaled Sulfur Hexafluoride gas, but I have had it injected into my eyeball."
Holy cow! I couldn't imagine anything worse than the Microtome used during LASIK until I read the description (and saw photos) of a Vitrectomy. I hope you were asleep.
During my LASIK procedure, my doctor warned me that the laser was about to start. When it fired its 219 pulses over about one second, I watched the ring of LEDs surrounding the laser go from an oval to a circle (mostly correcting astigmatism). I'd never actually "seen" a circle until that moment. All the more entertaining with the dose of Valium circulating through me.
Holy cow! I couldn't imagine anything worse than the Microtome used during LASIK until I read the description (and saw photos) of a Vitrectomy. I hope you were asleep.
Yes, that beats anything I ever had done to my eyes, including the predecessor to microtome use for LASIK when they simply scraped off the layer and gave you painkillers to make it through the couple of days it took the eye to regrown and close that layer (the pain is like a handful of sand in your eye - you're really not going to open it voluntarily for that time).
During my LASIK procedure, my doctor warned me that the laser was about to start. When it fired its 219 pulses over about one second, I watched the ring of LEDs surrounding the laser go from an oval to a circle (mostly correcting astigmatism). I'd never actually "seen" a circle until that moment. All the more entertaining with the dose of Valium circulating through me.
Valium is also a really good cough medicine. It doesn't actually help, but you no longer care :)
"Holy cow! I couldn't imagine anything worse than the Microtome used during LASIK until I read the description (and saw photos) of a Vitrectomy. I hope you were asleep."
Dunno about Dave, but during mine (as part of a retinal reattachment) I was quite happily wide awake (aside from the area around my right eye, that was well and truly under the control of whatever local anesthetic they use for this sort of procedure) and thoroughly enjoying every fascinating minute of it all - as someone with the typically inquisitive mind of an engineer, being able to experience something like that first hand was pretty amazing.
Especially since, being rather terrified of needles, there's probably no way in hell I'd be able to watch such a procedure in the third party, but when it's your own eye that's being worked on, the needles are conveniently out of sight... The follow up caratact removal op and laser clean up procedures a couple of years later were almost as much fun too.
And on a more practical note, the surgeon who did my original op did say they prefer if if people are able to go through the procedure with just local anaesthetic, as it makes the post-op recovery process easier when patients aren't needing to be brought back around from being under.
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Your not asking the right questions (but no downvotes for the jokes, that's ok...).
They just confirmed that by the looks of it, so far, it has the same mass as expected.
So before you ask "which way does it fall?", first think "what is it's mass?", then come back and decide what question is best to ask. :)
Experiments to answer the question Does antimatter fall down? were proposed in A Catching Trap for All Antiproton Seasons. The question is simple and relevant. The experiment is very difficult to perform. Electrostatic forces will dominate over gravity for falling antiprotons and antihydrogen, which is electrically neutral, is harder to make and handle.
For decades (and yes, it's made me decadent) I've toyed with the thought that anti-matter experiences anti-gravity in relation to matter. That would make gravity some little bit symmetrical with charge. Like charges repel; opposite charges attract. In gravity, like matter attracts; opposite matter, well, in this scenario, repels. I also wondered if anti-grav would make redundant all that dark matter / dark energy stuff they keep droning on about. If they're using laser beams (rather than the Scales of Justice) to measure mass, perhaps my anti-grav idea still has a few months of plausibility left in the can.
Given that pretty much all interactions with mass involve two bodies, would we notice if the mass of the antiparticle was negative? Gravitational interactions between +ve mass things and -ve mass things would produce a negative force, pushing them apart; two similar types would always pull together. Perhaps I need to think this through a bit harder though.
It is difficult to say what exactly a "negative mass" would be.
Possibly, when it comes into contact with normal mass, NOTHING remains (because negative mass implies negative energy, so you don't even get the angry photons of matter/antimatter encounters).
In Newtonian terms, one could make sense of the counterdirectional force vector, but in General Relativity, this is not so clear. Will geodesics through spacetime become hyperbolic?
During my brief visit to Meyrin, at the Antiproton Accelerator (AA) and Antiproton Collector (Acol) (part of the PS - Proton Synchrotron) we used to fire the occasional bunch of pbars at LEAR (Low Energy Antiproton Ring). LEAR was a cute machine, didn't need much skyshine shielding, and it successfully created the first technical antihydrogen atoms.
I'm still waiting for the AD (antiproton decelerator) experiment AD7 "GBAR" (Gravitational Behaviour of Anti-Hydrogen at Rest) to deliver.
their website is here:- https://gbar.web.cern.ch/GBAR/results/publications.php
you just don't want to know how we made/make the pbars - a lot of high energy magic from the unseen university of Sheffield!
"In antiprotonic helium one of the atom's electrons is replaced with an antiproton – it stays in orbit because, like an electron, it carries a negative charge."
That's some particularly clever precision atomic "surgery" to swap an electron with an antiproton. Although EXTREMELY unlikely I would understand any of how they managed to do that, it might be an interesting read.
Scanning the abstracts to the papers, it doesn't look like anything obscure. The low energy anti-protons can scatter an electron out of the He, as just about any charged particle would. The charge He ions can capture the -ve anti-proton. Might even happen as a single step event ( I'm not sure - didn't dig that far).
ashamed to say that many of my CERN experiments were held together with the Ferney Voltaire equivalent of Sellotape. Many things were tried, tested & rebuilt after a few weeks. Of course, the biggest experiments used the best kit eg detectors who only use/used ROMAN lead (keels etc) from ships that sank a millennia or two ago, these foundling shielding Pb not having the post 1945 background crap found in non-submerged lead. In general everything worked, mostly very reliably, but often it just was needed for a short time. My 168 metre AA became AC then AD and was rebuilt 3 times in 4 years!
Years ago I had a student working in our lab build me an junction box, because everything he built was beautifully made, far, far better than I could do. He came back the next day with the finish box and I had the sad job of having to ask him to re-wire it again, only this time more sloppily coz those 2 wires mustn't run parallel. I'd forgotten he was going to make the internal wiring look as neat as everything else. Oh well, I should have been clearer.
There is no space and no time for "wiring standards". Keep telling the muppets this, yet, they come up with ever more convoluted schemes of ordering and classifying, processes and procedures, and 3D-"tools" and "Tool Integration" - aka - binding that one tool that happens to work to the albatross, dead-ender, PLM system so Nothing Works (but, Consistency is most important of people of little minds).
In the end, time will be up, there will be no more physical space than there was the last 3 years and thus the contractors will cram everything into whatever orifice there is to be crammed full of stuff!
After seeing that CERN image,I promise never ever to complain about the rat's nest of cables behind my computers again....
Henri
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