Domain: particleadventure.org
Stories and comments across the archive that link to particleadventure.org.
Comments · 24
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Wrong site: try the particle adventure
The Wikipedia article linked is exactly what you would expect from an encyclopedia entry. A few paragraphs of introduction about what the electroweak force is, the people who wrote the theory and the experimental evidence which backed it up. Then it launches into a more detailed description of what EW interactions are, EW symmetry breaking etc. which has to be at a more technical level because otherwise you are leaving out information which is not what an encyclopedia is supposed to do.
If you want explanations of topics which are accessible to the general public then you do not go out and read an encyclopedia you go and read a book designed to simplify complex topics enough that non-scientists can digest them. So if you want a general public level explanation of EW interactions on the web go to something like the particle adventure and they'll have what you want there. -
Re:This would be more reasonable if...
Murray Gell-Mann sure as hell read (maybe skimmed?) it, though he might be the only one...
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Educational
I learned the difference between a fermion and a boson watching Big Bang Theory: http://www.particleadventure.o... The humor isn't always great. But, the show is entertaining to me and my wife. The physics on the boards is correct also.
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Re:Terrible names
Try the labeling of quarks.
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Re:I'm just curious
I found this site for the educated layperson, that gives a quick overview of particles.
It might be of interest to GP that gravity affects antimatter the same as matter.
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Re:really?
Everybody knows electrons are blue!
NB:
Its the same with quarks but they are not blue ;)
http://www.particleadventure.org/quarks.html -
Re:Confused
how fast things can change:
Gravity affects matter and antimatter the same way because gravity is not a charged property and a matter particle has the same mass as its antiparticle.
So the above is no longer believed to be true? -
Re:heavy elementsI would start with a chart of nuclides and a chart of the current model of subatomic particles to investigate the chain of fusions and fission.
I hope you like physics, though. The chart of nuclides can be a bit confusing at first.
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Re:Offtopic? Maybe.... SM not working.
Do they think it's correct or not?
They all start with caveats. They point out that gravitons are missing. The first article points out that the model is applicable over a wide range, not a fundamental theory that purports to explain all physical phenomena. Compare with a statement like "quantum mechanics is one of the pillars of modern physics" in Wikipedia's article on Quantum Mechanics. Even the last article you quote, which looks like it's aimed at kids, is happy to point out lots of issues with SM. I think it's pretty clear that the Standard Model has a quite different status in the eyes of physicists to theories like QM and GR. For example many physicists study all kinds of models that are not based on SM, for example String Theory. But very few physicists study alternatives to QM or GR. Studying alternatives to SM is standard stuff, studying alternatives to GR and QM is controversial.Maybe the problem you point out is in the popular press. They have a habit of making science stories seem absolute, and then take great delight in reporting when these absolutes no longer seem to be valid. But that problem doesn't just apply to SM.
And offtoptic, but I have to mention it. Why, since a month or so ago, do I have to use <P><P> for my first paragraph break but just a single <P> thereafter. It's very annoying!
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Re:Offtopic? Maybe.... SM not working.You and I are on the same side--unfortunately, a lot of the physical community is not. How many times have you heard or read something to the effect of: "[T]he Standard Model is a well established theory applicable over a wide range of conditions."(1) Or maybe: "To date, almost all experimental tests of the three forces described by the Standard Model have agreed with its predictions."(2) How's about: "Experiments have verified its predictions to incredible precision, and all the particles predicted by this theory have been found."(3)
I didn't argue that it's fundamental, whatever that means; I argued that physicists love the hell out of it because it's so accurate. I've just always considered its importance overblown because a lot of it is twisted to match the data. I'm not joking when I write that the community is considering adding ten more free variables to it. That's what they need to make neutrino oscillation work. You tell me, if everyone and their dog thinks it's a kludged up piece of shit, why does it still get accolades like those I've quoted--normally only with the caveat that "it doesn't cover gravity?" Do they think it's correct or not?
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Re:Quarks?
This: http://particleadventure.org/particleadventure/ is really a quite good layman's introduction to particle physics. The site is not the best designed, but the content is quite accessible, without being too inaccurate. Give it a go.
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Re:another possible idea
an electron is made of leptons.
err... Ahem. Strike 2.
here ya go. -
Re:Who says there's not an anti-graviton, anti-pho
The Standard Model of particles says there's no graviton, that's who!
:)
You said:
"No, the graviton can very well have an anti-graviton and a photon an anti-photon. The argument against it would be that both things don't have a charge...well neutrinos don't have charges either, but they have anti-particles."
You're misunderstanding why Photons Gluons and presumably Gravitons, if they exist, do not have anti-photons, anti-gravitons etc. and are actually THEIR OWN ANTIPARTICLES. It is not because they have no charge, that's irrelevant, it's because they are Bosons which are particles with integer spin. The chargeless Neutrino and anti-Neutrino are Fermions which have non-integer spin. I would suggest a look at CERN's The Particle Adventure site if you want to learn a bit more about subatomic particles, it's a great site.
However, this being said, there is a very tiny chance you may still be partially right about gravitons (though it's not your fault :] )since we've never actually observed one and there are hints that the Standard Model may break soon (though it must be noted that it is the most sucessful theory at describing our universe ever devised). Then who knows what the superseding theory (supersymmetry? strings?) will say about quanta of gravity.
Disclaimer: IANAP but I do know a thing or two about physics (if there is a physicist here and I've made a mistake in my post please feel free to correct me, though I'm fairly certain the contents are accurate).
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Primer to get you up to speed on current theory
I know more about string and particle theory than 99% of the population, which means I'm still a comparative dumbass on the subject in relation to people who really know what they're talking about.
However, here's a spiffy chart of the current "standard model" to help people get up to speed. Especially helpful for those who don't normally deal with Mesons and Antibayrons on a regular basis... -
Re:Not Antigravity
If you view gravity as nothing more than the curvature of space-time (as opposed to a "force") caused by the presence of mass, then there's no way to obtain an "inverse curvature" at a given point in space. Hence, there can be no anti-gravity.
However, if they find that there is indeed a mediating particle (graviton) for the gravitational force, and one could lessen the effects of those particles or even block them, the gravitational force would thus be lessened or blocked.
Perhaps something analagous to a Faraday cage for gravitational effects. -
Coolest name for matter ever!
I'm going to name my band "Quark-Gluon Plasma". All my fans will call it "QGP" for short. It's much cooler than "Bose-Einstein Condensate".
On a slightly more serious note...
The article links to a helpful physics primer if you, like me, need a little help understanding subatomic physics. (I'm just have a lowly Math degree.)
A little googling turned up this awesome page on subatomic particles called The Particle Adventure. This is the most accessible physics lesson I've ever received. Awesome.
This is the most fun I've ever had with subatomic physics: Quark Dance!
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Re:One electron says to the bartender ...
Forgot to add:
There is a quark named "down", but it doesn't necessarily have a spin oriented downward. Like an electron, it has a 1/2hbar spin which can be oriented in any direction to conserve angular momentum.
Here is a click-through standard model chart, and Here is an easy description of electron spin. -
What is a baryon? Here you go...Here is an excelent website that helped me understand baryons. Call it a Subatomic particles for dummies type site.
http://particleadventure.org/particleadventure/fr
a meless/startstandard.htmlStraight to baryons:http://particleadventure.org/particleadve
n ture/frameless/hadrons.html -
What is a baryon? Here you go...Here is an excelent website that helped me understand baryons. Call it a Subatomic particles for dummies type site.
http://particleadventure.org/particleadventure/fr
a meless/startstandard.htmlStraight to baryons:http://particleadventure.org/particleadve
n ture/frameless/hadrons.html -
Re:what are they hoping to find?
Yes, radioactive materials release energy, but not heat (usually) during regular breakdown. The release three main types of rays/particles; alpha, beta and gamma. Alpha particles are helium nuclei (i.e. 2 protons and two neutrons), beta particles are free, high speed electrons and gamma particles/waves are high energy photons. For more info this site has a good description (basically the saem as in this post now that I look) plue some pics.
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Introduction to particle physics
Well, it's not a book but I think ParticleAdventure.org is really great. In fact, it's on of the best site on the net!
Furthermore you should have a look at QuarkDance.org ;-)) -
Re:Earths gravity...Back to #2, I was looking through many of your comments for the past several months, and I noticed this one:
Hey, does anyone know why I have a score of 0 and my karmas at -3? I post some pretty darn good comments!!! Any suggestions?
When you Karma is negative, you automatically get modded down to 0. And I'm sorry, but no, you don't post good comments. I'm not trying to insult you here, but they often seem naive and whimsical. When you try to be funny, you're not.
Case in point: this
You seemed to be talking out of your ass. Gravity is probably NOT quite like EM. Also, the Weak force is many many many times more powerful than gravity. Look at this chart. It some cases, it is almost as strong as EM.
A tip for good karma: People like it when you have links to support your point. Learn HTML and put links in your comments whenever possible. Google is great for finding relevant information.
Sorry, and I hope this helps. -
Re:Not so fast....
General relativity is fine, but we have no way of reconciling it with quantum physics.
Basically that's my point. Whatever happens general relativity won't be affected in any *substantial* way at long distances. That means no anti-gravity devices, etc.
Quantum effects will become importent at *SMALL* distances, like 10^{-20} cm.
Discovery magazine listed as one of it's 11 unanswered questions for modern physics [doe.gov] "What is gravity?". Maybe you should write in and explain it to them?
:)They're trying to sell copy. I'm not going to fault pop-sci publications for trying to do that. But from a *PRACTICAL* point of view we understand gravity at large distance scales. Just like we understand mechanics at large distance scales.
The Standard Model of particle physics does not account for gravity. It is assumed there is a carrier particle for gravity called the gravitron, but this has not been detected.
This is not an assumption of the standard model. The standard model simply ignores gravity altogether. And yes I know that many pop-sci sites talk about gravitons, etc. but there not a part of the standard model.
If anyone is still reading this thread, many many illuminating links can be found from this google search
Random webpages are not a good place to learn particle physics. I've collected a number of links on my webpage which have good quality material. I'd particularly recommend the particle adventure for a quick review of the basic facts.
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Information on NeutrinosOne of the best sites for information on particle physics (for non-specialists) is The Particle Adventure.
Neutrinos are the least studied elementary particles because of they interact very, very rarely. It's no joke that they can "pass through matter like smoke", as the story said. The typical neutrino can pass through several light-years of lead without interacting once. The only reason they can be detected at all is that a tremendous number of them pass through the Earth every second. I forget the exact number, but it's something like trillions per square meter per second. Even so, a decector the size of SNO will only see a few hundred events per second. On the other hand, this is also why neutrino experiments like SNO or Super-K are so exciting for astrophysicists. The light that we see from the sun has all come from the surface, photons produced in the core can't make it through the sun to get to the earth. Neutrinos produced in the core can easily penetrate the whole of the sun and reach the earth. As a result, a very good neutrino telescope can look directly into the core of the sun. There are a berzerk number of other reasons to be excited about neutrino experiments, see the Particle Adventure for more.
Oh, and if you thought the SNO picture was cool, check out some of the photos on the Super-K, they've pretty much won the best-looking physics experiment ever contest.