Matter/anti-matter
Nothing really matters. Anyone can see.
It's only a small thing, but it could be big news: researchers at CERN have turned up the first evidence of exotic (and short-lived) atoms with pear-shaped nuclei. The reasons the boffins are excited is they believe the eccentric nuclei can help them probe one of physics' official Big Questions: how come there's something …
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Let's see - they smash a heavy atom into another not as heavy atom and the shape is asymmetric? hmmm. If a big car hit a not so big car, would one be pear shaped? just saying. Maybe the image they captured is at a moment of recoil. It would reason that atoms deform under appropriate stress.
The fact that this image is produced is amazing enough in itself don't u think?
"I studied to be a quantum mechanic. I had to give it up. I never knew whether the tool I needed would be in the toolbox until I opened the box. It was very difficult to grasp a quantum part."
I took the exam to be a quantum mechanic and everything: when I asked if I'd passed, they said "yes and no".
However I recall a very old documentary on relativistic physics which talked about communicating with an alien race that might be made of anti-matter, making any meeting with them a very bad idea.
But how could you devise a test to find out if they were?
There is a difference. IIRC it was all about the asymmetry in gamma ray emissions from certain nuclei.
What I can't remember is if this demonstrated both a difference in emission angle and amount, which I think would be necessary to ensure the matter (over time) outnumbered the anti matter particles.
But definitely intriguing. Thumbs up for some neat physics.
If you want to test what would happen we could always use chavs! See they do have a use after all.
Back on topic, although not entirely understanding what the hell is going on at CERN (brain not big enough!). I applaud the fact that they are doing something to further figure out what is going on in the world. It shows that we don't know everything (and yes religous nuts, I am looking at you!), but we are not afraid to look! (still looking at you religous nuts)
I think I saw that documentary, too, donkeys years ago. IIRC, it revealed that a certain isotope of cobalt is seen to preferentially spit out electrons (beta decay) in a different way to its antiparticle.
The fact that there is an asymmetry in the universe has always troubled me. I imagined that if I was God, and created a left hand and a right hand, how would I know which is which? For a human, it's not too hard to do, because we're surrounded by large scale asymmetries, like generally having a heart on the left, and halves of the brain that work in different ways. But if you're the supreme being, dealing with the building blocks of nature, there can be no such external reference. "This is an anti-particle because I say it is, and this one is a particle because it's the opposite of the other one that I said was an anti-particle" sounds like a bit of a dodgy argument. How God gets away with it is a mystery to me.
And a mystery to me, it's likely to remain, since descriptions of the subject bring horrible imaginary numbers and matrix multiplications into the frame. Far too baffling for me to understand.
Ohh cmon, you know Im not on about the average, run of the mill, garden variety religious nuts. Im on about the religious nuts who believe the world was created in 6days with a 7th for rest 6000 odd years ago or the whackadoodles that blow themselves up in the name of (insert invisible deity of choice here) to "further their cause"!
The general belief is that the universe started symmetric but unstable, or evolved to become unstable, and then spontaneously changed into a more stable but less symmetric configuration. Imagine a ball perched on a mound in the exact middle of a dish, with perfect rotational symmetry about the Z axis. Precisely because it is perfectly symmetric, the ball doesn't move. The slightest fluctation of anything changes the situation from metastable to unstable. The ball starts to roll. Once this starts, it will ultimately settle down to stability in a lower part of the dish, displaced from the centre. The arrangement of ball and dish is no longer symmetric about its Z axis. Incidentally the ball is also merely metastable with respect to rolling to and fro in its sponaneously chosen X-Z plane and won't "ignore" its freedom to also move in the Y direction for very long.
If you ask how it got onto the mound, one answer is that the dish itself always retains perfect rotational symmetry, but is evolving in shape from one with the lowest point at the exact centre, to one with a mound at the centre. At the critical point where the centre is no longer the low point, the ball ceases to be stable and becomes metastable.
"I think I saw that documentary, too, donkeys years ago."
I don't know about the documentary, but you've remembered the experiment and, yes, this is fairly old stuff. I found out about it from Martin Gardner's "Ambidextrous Universe", which was itself first published before my time. I think he was the one who introduced the Ozma problem of talking to anti-aliens.
http://en.wikipedia.org/wiki/CP_violation
http://en.wikipedia.org/wiki/The_Ambidextrous_Universe
If the idea that antimatter has an inane dislike of crowds ever gets proven, then I do believe the answer to all this matter we happily gaze upon will be upon us.
Just like in a nuclear explosion, most of the material, as in almost 100%, gets explosively dispersed before it gets the slightest chance to go pop itself.
So, big bang. Matter and antimatter gets dispersed at light speed and bugger me, the antimatter just keeps on running away from all its neighbours and hence the disparity we "see" is not a disparity at all.
So, where's all the antimatter then, if it didn't hang around for the year zero party?
Well you know that weird dark stuff, we can't see, touch or sense, but seems to have a gravitational influence on galaxies and the like, well, err, might I suggest the gravitational effect is actually an anti-gravitational effect from the antimatter that prefers life outside of matter's domain and similarly likes to keep everything out of it's.
That antimatter dislikes company and actively pushes against all contact, might also point to the often not asked question, where are all the antimatter stars and black holes?
I get paid sod all for my scientific ponderings, so for those of you who can't take their eyes off the money, might I suggest you jog on and get back to me several years and several trillion dollars later.
but difficult to interrogate it's gravitational properties when it is swathed in a magnetic flux several orders of magnitude greater than gravity.
However some tentative experiments in our matter infested world has thrown up results showing antimatter does have anti-gravity properties.
Actually, that has not been tested yet. There are some experiments currently underway; this is one: http://home.web.cern.ch/about/updates/2013/04/alpha-novel-investigation-gravity-and-antimatter
Unfortunately actually measuring the motion of an atom of antihydrogen when you drop it is kinda hard, and the results aren't anywhere like conclusive.
I thought the point about the apparent asymmetry of matter and antimatter was that there was an excess of matter, and so I suppose that almost all, or perhaps indeed all of the antimatter was annihilated. The same happened to _most_ of the matter, but since there was an excess of matter, what was left after the mutual annihilation is what we now see.
Nevertheless I stand ready to be corrected.
We detect the existence of matter by the energy it reflects or emits.
If AM is as shy as I consider then;-
1.. It will avoid interaction with everything and therefore not be reflecting anything.
2.. Will not interact, even with its kith and kin and therefore not emit anything.
I suppose once the vastness of space is considered, it can easily be realised how widely dispersed antimatter can be, so like a neutrino can pass through a planet, energy can pass through space without ever hitting antimatter. Hence, we can't see it.
Elusive dark matter? Pah! Antimatter and nothing more.
Yeah Eadon, it would be reeeeallllly surprising if antimatter behaved differently than normal matter in its spacetime bending behaviour.
After all, you can seamlessly transform matter into antimatter with a bit of E=mc² and some luck, and nowhere do we see negative signs appear suddenly in front the constant total mass energy.
Might be a neat null experiment but I wouldn't want to bet my PhD on it.
tl;dr ; gb2 slagging Windows.
I'm not too sure what I am supposed to be seeing there, and what the colours mean. My initial thoughts would be that it's some form of probability graph, that a proton/neutrino is likely to exist on there, very likely on the dark red through to not so much on the blue.
Is that right, or am I waaaaay behind the rest of the class here?
We don't yet *know* if antimatter responds to gravity the same way as matter, but we are pretty sure it does; if it doesn't, it would really change our understanding of the universe.
The reasoning goes like this:
An object in free fall is following a straight line in space-time (the line may not seem straight in space, but remember, we are seeing a slice along the time axis, not the full line in space-time. That's why we say "gravity curves space-time", or more properly, "gravity IS a curvature of space-time.").
Now, consider if you had something that had a different response to gravity than normal. Let's say you have a ball that has an inertial mass of 1kg (that is, a force of 1N will accelerate it at 1m/s^2), but experiences a force due to gravity on Earth of 1N rather than 9.8N. You let your "odd" ball and a normal 1kg ball loose at the same time, close enough that the differences in the curvature of space-time are negligible. The normal ball will have 9.8N of force on it and will accelerate at 9.8m/s^2, the "odd" ball will have a force of 1N on it and will accelerate at 1m/s^2. But, in theory, both are just following a straight line in space-time, and since we've constructed the experiment that the lines should be the same, we have a reducio ad absurdum - we've created a paradox. So, the reasoning goes, inertial mass and gravitational mass must be the same. And since we do have a very good set of evidence that antimatter has positive inertial mass (things like the recoil of an atom releasing a positron, for example), we thus have a strong reason to expect antimatter to react the same to gravity as normal matter.
The experiments with trying to prove that are difficult, as we cannot just make an "odd" ball of antimatter and drop it - the quantities of antimatter can can make are small, they tend to come into being moving very fast, and even if we can slow them down to where gravity is a significant factor, they don't stick around very long (they tend to fall down, find some matter, and go FLASH in a very short period of time). So the error bars on the experiments are pretty large - we can say that antimatter is less than 100 times more strongly attracted by gravity than normal matter, and not less than -60 times as strongly attracted (read: repelled) as normal matter. That's like saying you have found by experiment to have between -60 and 100 heads - we suspect the real answer is 1, and -60 < 1 < 100, so our experiment has not disproved our assumption.
Now, if we ever did find an "odd" ball - be it antimatter, or floobydust, or whatever, but that didn't respond to gravity the same way as normal matter - then we'd have to rethink general relativity in a pretty big way, a way as big as general relativity was for Newtonian mechanics. That might happen: we know that quantum mechanics and General Relativity don't fit together, and we know that quantum mechanics and General Relativity are pretty good descriptions of the universe in their own domains, and we know the universe contains both the domain for which quantum mechanics is valid and the domain for which General Relativity is valid at the same time, so we know we don't know everything. A major re-think like that might explain a lot, but since we have no data that would shape what that rethink should be, we cannot start it now. And that's what experiments like this are good for: they give us that evidence to say "OK, this is the direction you need to be looking in."
Bosons are commonly their own antiparticles. The commonest such particle is the photon. Observation of light in gravitational fields on distance scales from smallish (Earth-Sun) to comsological show that photons are attracted by massive objects much as predicted by Einsteinian gravitation. And since they are their own antiparticles, then antiphotons are likewise attracted.
We don't know of any Majorana fermions - ones which are their own antiparticles. The equations don't rule out such particles, and neutrinos are not yet well-enough understood to rule them out as candidates. But gravity acts alike on bosons and fermions, so it would be a major asymmetry if it acted oppositely for antibosons compared to antifermions!
A major re-think like that might explain a lot, but since we have no data that would shape what that rethink should be, we cannot start it now
Sightly too strong. If a theory of everything exists that supercedes both quantum mechanics and gravitation, it might be concieved of tomorrow by a mathematician of genius. If it were simpler than the existing two irreconcilables, I'd wager Occam's razor that it was right. And it would probably make predictions which were at odds with one or other of the existing theories, which would then help the experimentalists know what to look for.
It wouldn't be the first time that the theory came first and observations that confirm the theory later.
Some might say that the theory *has* to come first, otherwise the universe wouldn't know what to do. And a few would say that it didn't, until something somewhere started thinking. Philosophy, again.
Including the very slight fluctuations in the spectrum of that radiation in different directions?
Continuous creation for infinite time would even the background radiation out in all directions, unless you're prepared to countenance that empty space has different properties in different directions as viewed from here.
The big bang hypothesis predicts that there should have been quantum fluctuations in ther very early universe, the signature of which would be seen as anisotropy in the cosmic background radiation. Those fluctuations have now been observed, at levels that are not hard to reconcile with the hypothesis.
Today i hav a strange dream, i dream a "chair" made out of many lines can be easily goes to Four-Dimensional State by twisting and bending its lines. However, this "chair" cannot goes to Five-Dimensional State because it will be destroyed completely. In contrast, a particle can goes to Five-Dimensional State by this way: A single point was turned to became a "chaossy" line.
Don't knock such visions ... but unless you can retrieve the underlying meaning, if any, and set it down in the language of mathematics, you'll find it hard to convince many people that it's anything other than a purely subjective imagining.
Organic chemistry was given a huge advance by Kekule, who dreamed of a snake swallowing its own tail and backtracked to the structure of a benzene molecule. Newton reputedly cracked gravity because of a falling apple, or its effect on his head. Many mathematicians and some scientists are Platonists. They believe that mathematics is the language in which the universe is best described, because it exists independantly and timelessly outside of all physical reality. Like most philosophies, it's hard or impossible to disprove, and I believe in Occam's razor! But allowing that they might be right, perhaps we do all occasionally come back from wherever we go when asleep with faint and scrambled recollections of the deepest of realities, and sometimes manage to reconstruct another tiny facet of the infinite?
The universe is much bigger than we think...
There was as much matter as antimatter...
Local inhomogeneities in the matter/anti mix persisted through the expansionary (inflationary?) epoch...
We live in an expanded region with an abundance of matter...
There are other regions that have an abundance of antimatter...
Globally the universe is in balance qua matter & antimatter...
Where's my Nobel, heehee?
cze
One can think that at this scale w can see the object "streched" in the time dimension. We only see it in a transition stage across past, present and future events. So the object still might be symmetrical after all.
It bends time and visually it looks like a mini black hole, maybe similar to the one from theory of prof. S. Hawkins.
"TIme is like a black hole vortex , we fall from the past into the unknown darkness of the future."
P.S. In my professional opinion ( as a taxi driver ) a wormhole bridge between two points in space can be created by constructing two black holes made of entangled particles.