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NEWS!
Update on higgs search from CMS and ATLAS at stream here.
2.4 sigma (global) signal for a standard model Higgs at 126 GeV.
If you want a better writeup about the Higgs than mine below, I recommend wikipedia.
The new ATLAS results can be seen at their page.
Introduction
Do you know how when you read about starcraft in daily newspapers it often seems to send a message that doesnt feel accurate? That they somehow miss the point? That they easily focus on some part of it that they find sensational, motivating their article, and blow it out of proportions? And that's not even mentioning the comments the article will get, or what you will read on non-gamer forums.
Well, that is what I feel about particle physics sometimes.  Today, I will take the time to try to provide an unbiased inside view of one of the usual topics covered in newspapers and forums. With some luck, some of you will be able to understand some things a bit deeper, and some may even manage to look through some of the articles you will run into. 
I will try to do it an accurate manner, or at least be honest where I skim thinks over, while still keeping you awake. I also added lots of images!!! :o
I will start by writing a bit about the search for the Higgs particle. If I find the time, and if people seem interested, I may add more topics.
EDIT: I also just realized that I actually have a 10-15 page introduction to particle physics that I wrote for my thesis! So if anyone has the time and wants some background, here is the .pdf: http://www.mediafire.com/?c5eczxbalqm2o0f
![[image loading]](http://i.imgur.com/KFVpQ.jpg)
Ok, after having spent half an hour making the title image...
What you hear: mythbusting
If you ever have heard of particle physics, you have probably heard of the big accelerator they built in Geneva. If you have read an article about it, you will know that the name of the accelerator is "LHC": Large Hadron Collider, and is situatied in CERN: Centre Europe Research Nuclear, or however the french guys spell it. The article usually mention that they collide protons with each other.
So far, all this is accurate!!
It then diverges a bit depending on the angle of the article. Some of them (the more serious ones in general) continue and ask why this was built. A very interesting question for that matter, but I'll try to stay on track here.  They will in general end up spending a lot of time talking about the search for the Higgs particle.
Also this is pretty accurate.
Of course, you could go on some economical tangent here and argue that it is built just to get money for all the useless particle physicists. While there may be some merit to that approach, I will ignoring that for now, and just leave say that I'm pretty sure the Higgs takes a big role in any official motivation they send to governments.
As it sounds fancy, you will often hear things along the lines of "recreating the big bang".
- It makes very little sense.
The one thing you could say is that "we accelerate particles to an energies that hasnt been around since the big bang". That would of course also be innacurate, but as the statement is a bit more specific, it is now wrong in two ways.
- We get hit by particles with thousands times as much energy from cosmic rays on a daily basis.
- You shouldn't be talking about "big bang" here. Rather "the early universe". The big bang, the actual time = 0 start of universe divergence, is so full of infinities so it shouldn't even get close to a cute little particle accelerator. Also, of course, we have no idea if there were any time = 0 start of the universe divergence, as it is impossible to get any data from a divergent point. Not that it'd be a point either, but in lack of better words. We do have some pretty good astronomical observations giving us information about the early universe though. The article will go for the sexier "big bang" every time though.
Many articles and interview use the word "the god particle".
- This is not used in the scientific commuinity (as you may have guessed), or when it is used, it is for the lulz, and will cause smiles and giggles.
- Well, fine, call it what you want. >_>
An ambitious article will then go on and try to explain what the Higgs is, why it is so important, why we need this huge thing to find it, and why we hope to find it with this huge thing. At this point, the articles differ wideley depending on who they asked for information, and how the repporter chose to interpret the answer when he didnt understand it.
- Some are decently accurate, but very few manage to actually communicate any accurate information to the reader in a way that makes sense. The most accurate ones tend to make sense only to people who already know the field, while non-physicists will skim or skip that part.
- Others oversimplify, and make some analogy that maybe makes sense in one way, but that is extended far beyond the reach of the analogy, giving a very odd picture of things.
- Others yet (better not give examples, or what do you say new scientist?
 ) just dont bother with what is accurate, and write whatever sensational things they feel like that day and present it as truth to sell better.
So finally, let me try to give my explanation to what is actually going on with the Higgs at LHC.
The current state of particle physics
Yes, I need to take a step back. Some context is needed to understand how things fit. It'll be brief, dont worry. + Show Spoiler +That's what SHE said!!!!! ZINGGG!!!!!1111oneone
So, essentially, most things are sorted out. We can predict or at least explain all experiments (with very few exceptions) very well. Some with crazy high accuracy. Imagine firing a ball across the atlantic ocean with some cannon or catapult or whatever. Imagine some device measuring the speed of the ball as it leaves the firing device. Now the measuring device has a model for air resistance, wind, rotation of the earth and everything that can be used to predict where the ball will land. It can predict which house it will hit on the other side. Let's say its some kind of supermarket. The model can predict which row in the supermarket it will hit. Let say, it will hit the kitchen section. Lets say its a small ball. Then it can predict which thing it will hit. Like for example a cheese grater. Let's say its a REALLY small ball! it can then predict which hole in the cheese grater it will pass through. It will predict if it will bounce of the lower of upper end of the hole. From the other side of the atlantic. Thats the kind of accuracy we are taking.
![[image loading]](http://i.imgur.com/8eOcW.jpg) An iPhone touch pad does not have much accuracy in the 8:th digit.
So how is this explained so well you ask? Actually im pretty sure you dont, but nm that. Ill answer anyways. It can actually be formulated very neatly in a way that bring the matter and the forces together. One principle to rule them both, one principle to find them. One principle to write them both, and in the Lagrangian bind them. In the land of CERN, where the LHC lie. + Show Spoiler + Let's not get into detail on what this principle is. Let's just be happy that there is a single principle that can describe essentially all data.
+ Show Spoiler [Physics details] +What I'm referring to here is Gauge Symmetry. When you build a quantum field theory theory (which is how you do a particle physics theory, if you want it to be consistent with quantum mechanics and special relativity), you do it by writing down a Lagrangian. A Lagrangian is essentially only describing how you calculate the action (the kinetic energy minus the potential energy) of a certain configuration of particles (or rather fields, as particles are described by fields). A property of quantum mechanics (without special relativity) is that you can change the phase (that is multiply by a constant e^(i*phi)) of a wave function, and it does not change any observables. This is referred to as global gauge symmetry. In a Lagrangian, one would like to keep that property, and to further be consistent with the limited speed of light, one could make an argument for why the symmetry should be LOCAL. With local means that the phase depends on the position in space, ie multiplication by e^(i*phi(x)). So, gauge symmetry is to require that the physics do not change when yuo multiply your particle fields with a phase e^(i*phi(x)). Assume that you first put in a fermionic field, that means a normal matter particle like an electron. Looking at http://en.wikipedia.org/wiki/Gauge_symmetry#An_example:_Electrodynamics, you see that by requiring gauge symmetry you HAVE TO add the new field "A", which is the photon, the carrier of electromagnetism. That is, just by requiring local gauge symmetry and assuming that there are matter particles, you PREDICT the existence of electromagnetism! By requiring a more general gauge invariance you will get out also the weak and strong force. (from the rotation groups SU(2) and SU(3) for those that likes group theory).
A catch...
Well, of course, there is a catch. Namely that there is a measurement that blatantly violates that principle. Like imagine Flash playing your grandmother TvZ. On lost temple. Flash on 3, grandmother on 12. and your grandmother plays blind. Unless she already is blind, in which case she plays without sound. For you sc2 people, it is like a diamond player having a collosus in a PvZ vs anyone.
![[image loading]](http://i.imgur.com/2gl2s.jpg) This is where you mom went last night...
+ Show Spoiler [Physics details] +The problem is the mass of the W and the Z, the force carriers of the weak force. The photon and gluons are massless and cause no problem, but by putting in a mass term in the Lagrangian for the W and Z, you break the gauge symmetry. W and Z are measured to have very large masses in fact, just below 100GeV. Which is why I do the flash-analogy. Notice in the wiki link for gauge symmetry above that the mass terms for the matter particles (fermions) are fine. The problem is the mass of the force carriers.
... with a solution!
Luckily, some smart guys some while back came up with a sneaky little way in which the principle can be saved. A hidden particle that can make it LOOK like the principle is broken, but that actually conserves it if you look close enough.
![[image loading]](http://wiki.teamliquid.net/starcraft/images2/7/7d/Dark_Templar.png) Looking close enough?
+ Show Spoiler [Physics details] +Look at how electromagnetism forms from the fermionic kinematic term again in the gauge symmetry wiki link. Notice that it is the derivative that is not gauge invariant on its own, because when you derive the e^(i*phi(x)) you get an extra term from the derivative of the product. You then insert the field A which you define to have a gauge transformation that exactly cancels out that extra term from the derivative.
This is essentially the same trick. You have a term that gives you extra terms when you transform it. So you introduce a new field (associated to a new particle) with a gauge transformation that exactly cancels out the problem. So in the same way that the fermion symmetry breaking "predicted" electromagnetism, you can say that the massive W and Z bosons predict the Higgs.
Confirmation
Ok, cool! Well, to confirm that this actually is what is going on, let's look closer! How do you look closer then? Well, essentaily the answer to that is: build the LHC. This is related to the fact that small things can only be seen with high energies, but nevermind that here.
And when we build that stupid huge collider, what is it we expect to see that confirm the sneaky trick to restore the principle? Essentially, the answer is: the Higgs particle.
![[image loading]](http://i.imgur.com/OvedK.jpg) Yo dawg, I put the key to decay in the car, k?
+ Show Spoiler [Physics details] +Since the Higgs was not found at the LEP (a previous collider), it is know that it cannot have a mass below around 115GeV. Assuming it exists ofc. There are theoretical arguments you can make that makes it uncomfortable to have a higgs with a mass above around 180GeV. (because it would mess up the top mass through loop contributions or something, not sure about the details) So by building the LHC, which will cover masses far above that, we expect to find it if its there.
No Higgs?
All in all, Higgs has to be there for our neat explanation of the rest of particle physics to fit together. No Higgs means that we will have to revise how things are built up, and we may have to start questioning the master principle.
![[image loading]](http://i.imgur.com/GUDna.jpg)
+ Show Spoiler [Physics details] +If the lower mass range closes, we will start seeing a flood of preprints trying to explain how to make the theory fit. There is for example a wide range of BSM (beyond standard model: "new" physics) models that can hide the higgs, ie make it very hard to detect for the LHC, even if it has a mass below 200GeV. There are other models that bypass the arguments for why the higgs shouldnt have a mass below 200GeV. And then I assume there is a zoo of models that skip the entire Higgs mechanism, and solve the gauge problem in another way, of maybe even gives up gauge theory, what do I know? The one thing that is sure it there will be a flood of preprints, and that no one will know which are correct.
Current state in the Higgs hunt
So, how are we doing? LHC has been running for some while now.
The answer can be summed up in this plot.
EDIT: updated version of this plot in edit at top of post.
![[image loading]](http://i.imgur.com/7Amjh.jpg)
This is how the (standard model) Higgs hunt results are shown within the scientific community. Let me explain the plot.
- The Higgs particle has a mass. It's refered to as m_H or M_H in the plot.
- The Higgs decays into other particles really quick. What we hope to see are the resulting particles it decays into.
- There are other "normal" collisions (ie without Higgs) that can produce the same particles that the Higgs decay into.
- This makes it harder to observe the Higgs.
- Higgs with different masses decay into different kinds of particles. Some are more easy to pick out that others.
- With some Higgs masses it is easier to find the Higgs than with other Higgs masses.
- The current state is described by the black thick line in the plot.
- If the black curve is below the dashed straight line, it means that the Higgs does not have that mass with 95% certainty.
- If it WOULD have that mass, it wouldve been seen by now.
- In the other masses, where the black line is above the dashed straight line, we still do not know.
- As LHC continues to run, more and more masses gets excluded. ie masses where we WOULD HAVE found it by now, if it would be there.
- If the there is no Higgs, we will have closed this entire mass range down by the end of next year. If LHC runs as planned that is.
- People are mainly looking at the range below 155, to the far left in the plot.
- If there is a Higgs (in this mass range), it will be found before that.
Let me try to clarify a bit. At any given point on the x-axis, he further down the black curve is, the more sure we are that there is no Higgs with the corresponding mass. The horizontal line marks where we are 95% certain. So below 155 GeV we still do not know very well (actually the limit is down to 147 GeV now i heard on a meeting two weeks ago). It may be there, it may not. We are pretty sure that there is no higgs between 155 and 190, and not between 295 and 450. It may still be between 190 and 295 (for the experimentalists. most theory people dont expect to find it there).
The dotted curve with the error band shows where we EXPECT the black curve to be, assuming there is no Higgs. As LHC takes more and more statistics, the dotted curve with the error band will move down, as we will get more and more certain that there is no Higgs (if there is none).
If there is no Higgs, the black curve will follow decently inside the error bands (as it is now) and eventually will be below the horizontal line for all masses. At that point we can 95% exclude the Higgs, and there will be articles all over the news about it.
If there is a Higgs at a certain mass, the black curve will not follow the error bands down at that mass as statistics increase. The green and yellow area mean 1sigma and 2sigma deviation from the expected line. If it hits 5sigma above the expected dotted line, it will officially be labeled a discovery, and there will also be articles all over. With some imagination, you can see hints of that to happen around 135 GeV, 250 GeV and 600 GeV, but it can also just be a statistical fluctuation.
The moral of the story: In a year we will know!
QnA:
+ Show Spoiler +On October 13 2011 20:12 arbitrageur wrote:
Q: Why is LHC taking so long. What's the constraint(s) that stop(s) it from figuring out if it exists in a shorter time scale? + Show Spoiler [A] +On October 13 2011 20:21 Cascade wrote:
A: It is because of the protons the collide being a mess to disentangle. Actually you can get a hint if you read the part about the strong force in the .pdf i edited in just now.
Briefly, it is due to the proton-proton collisions creating A LOT of events that look very much like an event with a higgs. So there is a huge background to the signal in most cases. They record billions and billions of events, and only a few of them actually contains Higgs (if it exists). It is crazy hard to determine, among the billions of events, if some of them actully are Higgs events or not.
An analogy would be looking for a nail in a haystack, where some of the straws look damn similar to nails.
Soooo, that said, place your bets! Can TL predict the correct Higgs mass?
Poll: What is the Higgs mass?No, I will not give "over 9000" as an option.... (50) 38% No Higgs (31) 24% over 200 GeV (16) 12% 120-130 GeV (12) 9% 150-200 GeV (8) 6% 140-150 GeV (5) 4% less than 120 GeV (4) 3% 130-140 GeV (4) 3% 130 total votes Your vote: What is the Higgs mass? (Vote): less than 120 GeV
(Vote): 120-130 GeV
(Vote): 130-140 GeV
(Vote): 140-150 GeV
(Vote): 150-200 GeV
(Vote): over 200 GeV
(Vote): No, I will not give "over 9000" as an option....
(Vote): No Higgs
tldr: + Show Spoiler +
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Good write-up... dont know why it hasn't received any responses...
I think the flash/grandmother/dt analogy was a little too much though
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Good flash game. Would play again.
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What if the GeV range for Higgs contains an imaginary component?
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From a perspective of someone that doesn't really have any advanced knowledge of physics..
I wish this write-up didn't treat the reader as a retarded monkey, with lotr pictures, yodawg memes and starcraft analogies (that made no sense to me). Moreover it didn't actually answer anything. All I got from this is that we're looking for the higgs boson because we're expecting it in our magical equation for the world, and we expect to have the results within a year.
Can that get any more vague?
Thanks for writing it up I guess, but I'll go read the higgs wiki entry now to actually learn something. I guess this article wasn't aimed at people like me. At least it pushed me to learn a bit about this though.
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Sooooo where does anti-matter come into this?
Excellent Write-up btw, really actually helpful for those of us who really like physics but realized that you need a PhD to do anything of value and that takes 10+ years unless you're a supergenius
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On October 13 2011 10:01 Antisocialmunky wrote:
What if the GeV range for Higgs contains an imaginary component?
Mass matrices are hermitian I believe.
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On October 13 2011 10:21 JeeJee wrote:
From a perspective of someone that doesn't really have any advanced knowledge of physics..
I wish this write-up didn't treat the reader as a retarded monkey, with lotr pictures, yodawg memes and starcraft analogies (that made no sense to me). Moreover it didn't actually answer anything. All I got from this is that we're looking for the higgs boson because we're expecting it in our magical equation for the world, and we expect to have the results within a year.
Can that get any more vague?
Thanks for writing it up I guess, but I'll go read the higgs wiki entry now to actually learn something. I guess this article wasn't aimed at people like me. At least it pushed me to learn a bit about this though.
Excellent write-up.
Do note that a whole wall of text and graphs will shun away most of the people bothered to read threads like this. Also, you can find the 'un-meme'd' version in the interwebs. The OP is giving us a fun yet informative report on the Higgs particle.
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Great write-up, thanks for posting this. Perhaps you could shed some light on supersymmetry, and why we may be beginning to suspect it is not true?
I saw a talk by Shing-Tung Yau on his book, The Shape of Inner Space. The joke we came up with was that if supersymmetry turns out to be false, Yau will quit mathphys and soon we'll all be eating general Yau chicken
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Nice post, entertaining and informative. Write me up some quantum physics soon.
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Great post, I really enjoyed reading it. But then again I like to read physics stuff, thanks for the info!
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Oh god. I just feel empty inside now. Maybe I'm an idiot and people think this is fun but I just read this huge post and it didn't say me anything. That's a feat in it self I guess.
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With all the confusing analogies I am still confused.
What is the underlying assumption that predicts the higgs boson?
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The way I see it, they're just really close now to finding that it's not there.
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On October 13 2011 14:21 Robinsa wrote:
Oh god. I just feel empty inside now. Maybe I'm an idiot and people think this is fun but I just read this huge post and it didn't say me anything. That's a feat in it self I guess.
Don't worry, he didn't actually explain anything, so it's perfectly normal that you didn't learn anything.
The reason the Higgs is necessary is that the particles we observe have different masses. Other than the Higgs, there is nothing that would explain why particles containing the same number of quarks would have different masses, or why they even have mass at all. The Higgs give them their masses, and it is the last particle predicted by the standard model of particle physics to have not been detected yet, mainly because it requires very energetic collisions to produce these. That's why the LHC was necessary.
The standard model is what we use in microscopic physics. It allows for the existence of many particles and has been, generally, a huge success. If somehow, the Higgs does not exist, then there is something fundamentally wrong with the standard model. That would be a major revelation for all physicists and would likely lead us to make huge progress. In fact, finding the Higgs might almost be a bad thing, since it might very well confirm the standard model without teaching us anything.
I am personally hoping we don't find it.
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I voted no Higgs. God damn freelodaing particle physiscist asking us to build huge accelerators for them on a hunch. Inventing a particle so your reasearch avoids a dead end and trusting to the rest of the stupid community to just suck it up. "Oh yes there is this ghost particle you see....I can haz 10 billion euros to build big accelerator plx.....kk?" We want every penny back Cascade, you hear us? Every penny!
Also, good writeup.
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Basically, our extremely successful model for electromagnetic and weak nuclear interactions (the Glashow-Weinberg-Salam electroweak model) has as a very important component: a scalar particle that we call the Higgs particle. This Higgs particle has the property that certain symmetries of the electroweak gauge bosons (force transmitting particles) are broken by this particle. This causes the normally massless gauge bosons to acquire mass in a very specific way so that one boson remains massless and couples in the way we expect to charged particles to be identified with the photon, and the other gauge bosons (W+ W- and Z) have a mass. This mechanism is also the only way we know how to give masses to chiral fermions like the electron and quarks.
So, basically our theory of the electroweak interactions is very successful yet requires this Higgs particle for it to work. It is possible that the Higgs particle doesn't exist and our theory is wrong, but so far it has stood up to experiment so we have had no choice but to postulate that this particle exists. However, we will soon have the data to determine directly whether or not this particle really exists. If it does, thumbs up for our Standard Model of particle physics; if it doesn't, we can be pretty sure that the electroweak model breaks down at these energy scales, and we'll have to replace that model with something else.
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Sooooo, is any of this more directly related to the recent CERN findings that show a faster-than-light neutrino? Other than the obvious theory of relativity being broken.... does this affect the particle interactions you're talking about?
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How did it take you half a hour to make that tittle lol. I like the pictures you added through out the article. I have to reread this again, cause i got lost twice.
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yeah but what if my grandmother was jaedong
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After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
I originally clicked on this thread with high hopes and excitement. I left this thread feeling like I just slaughtered a kitten for taking the time to continue reading. While the original posters residence in Sweden grants him SOME immunity from criticism on proper English and syntax, the overwhelming amount of stupidity put into this work is clearly observable with a brief scan of the naked eye.
The only legitimacy I can grant to such an atrocious thread is that its title accurately summarizes the lack of essence to be found on Higgs particle research and actually correlates to what is actually being discussed. But for those of us such as myself who blindly click on anything scientific within TL, this thread becomes entrapment: assuring us that an enlightening wealth of information will be found only to become squandered and a joke.
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Sweet write-up, very funny but it doesn't exactly seem scientific... I voted that we won't find the Higgs, not that I know enough to make an educated guess. But just because humanity seems to get things wrong more than we get things right.
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very creative way of explaining the higgs particle! I enjoyed it thoroughly.
+ Show Spoiler + is "sence" a non-american spelling of "sense" or are there just some typos?
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I'm curious, are you actually a physicist? I've been hoping someone would come along and do this kind of thing for either the Higgs or the neutrino stuff for a while, but I can't really tell since the scientific content is so sparse.
I found the cannon-across-the-atlantic analogy cute and useful, and the description of the graph helpful.
Unfortunately, that's about it. The Starcraft analogies actually made things infinitely less clear than if you'd just said "if the Higgs doesn't appear, we need to rewrite these bits of physics," and for the rest of the content I could pretty much have read the tl;dr, which I would already have known (....if the tl;dr didn't turn out to be totally unrelated, anyway).
You also need to learn to spell "sense." It does not have a c in any permutation of English I'm aware of.
EDIT:
+ Show Spoiler + and since I'm Australian and follow British conventions, and the guy above me is American and said the same thing, I'm going to go out on a limb and say "sence" is outright wrong no matter where you're from.
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Do you know how when you read about starcraft in daily newspapers it often seems to send a message that doesnt feel accurate?
holy run on sentance!
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On October 13 2011 15:42 LarJarsE wrote:Show nested quote +Do you know how when you read about starcraft in daily newspapers it often seems to send a message that doesnt feel accurate? holy run on sentance!
Just you wait.
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While the effort is notable the op isn't really saying a lot (vaguely depending on what target group is within the group of those who aren't very familiar with particle physics).
I.e. More details wouldn't hurt. Explain the correlation (or, I believe causation considering you, as in the general "you" including you, assume the hb exists :D) to why according to the idea particles have mass now. How it's tied to a unified explanation of forces and whatnot. If you can find the time that is.
I just want to say that I, personally appreciate the effort for something I wouldn't do myself.
This post isn't meant to criticise you, merely tips on what I believe would make it a more informative post. I see a good first draft with potential.
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On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
I originally clicked on this thread with high hopes and excitement. I left this thread feeling like I just slaughtered a kitten for taking the time to continue reading. While the original posters residence in Sweden grants him SOME immunity from criticism on proper English and syntax, the overwhelming amount of stupidity put into this work is clearly observable with a brief scan of the naked eye.
The only legitimacy I can grant to such an atrocious thread is that its title accurately summarizes the lack of essence to be found on Higgs particle research and actually correlates to what is actually being discussed. But for those of us such as myself who blindly click on anything scientific within TL, this thread becomes entrapment: assuring us that an enlightening wealth of information will be found only to become squandered and a joke.
Agreed 
It's nice to try and dumb things down, but this doesn't really explain anything, and the analogies just don't really work.
Sorry!
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Good try mate. I understand what you were trying to do...and at least you managed to capture some of the frustration one experiences seeing ones field oversimplified and sensationalized to a fault. As a planetary scientist i cant tell you how painful it is to read through the exoplanet thread that seems to come up every couple of weeks. But you know...I guess its a symptom of spending most of my waking hour reading material produced by others who think about their respective thinking about said topics in painstaking detail.
The truth of the matter is...I dont think I have ever come across such a thing as a truly helpful description of any field of science in layperson terms...it really just doesn't work (I for one can't stand the popular works of Brian Greene for instance, despite the fact that he clearly knows what he is talking about). I think this is just an inexcapable problem, at least for math heavy subjects like modern physics, and it wasn't until I was a good piece of a ways through a physics major that I understood just why those science channel descriptions of theoretical physics are always so unsatisfying.
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On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
Can you at least verify if the statement that we'll "know in a year" if the Higgs exists or not is true?
Are there any sites/articles you can recommend to us to find out more on the topic?
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ok, thanks for feedback.
Surprised that there has been no flaming yet! keep the manners up guys!
I perfectly well understand the issues many of you have with the physics + meme concept, and I agree that there is too little physics content. I have added in a lot more hard physics in the text now, but in spoilers to not create a wall of text. I still want to maintain that very loose forum (even 4chan) style to it, otherwise, as mentioned, you can go to wikipedia.
what you think now?
And the sence-thing was embarrassing. :o
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On October 13 2011 15:42 LarJarsE wrote:Show nested quote +Do you know how when you read about starcraft in daily newspapers it often seems to send a message that doesnt feel accurate? holy run on sentance!
Nice spelling there!
So the short version of this is that if we get the weight then current theories are proved correct. If we don't get it then the boffins have to go back and rewrite science?
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On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
I originally clicked on this thread with high hopes and excitement. I left this thread feeling like I just slaughtered a kitten for taking the time to continue reading. While the original posters residence in Sweden grants him SOME immunity from criticism on proper English and syntax, the overwhelming amount of stupidity put into this work is clearly observable with a brief scan of the naked eye.
The only legitimacy I can grant to such an atrocious thread is that its title accurately summarizes the lack of essence to be found on Higgs particle research and actually correlates to what is actually being discussed. But for those of us such as myself who blindly click on anything scientific within TL, this thread becomes entrapment: assuring us that an enlightening wealth of information will be found only to become squandered and a joke.
.. Sheldon Cooper.. ?
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So fitting that I am wearing my Torso friendly hadron collider shirt. Anything physics related usually gets me interested.
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Ok, added an general introduction to particle physics as well that I wrote for my thesis. Its quite long, and has to be downloaded in .pdf format, but maybe someone will enjoy it.
On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
I originally clicked on this thread with high hopes and excitement. I left this thread feeling like I just slaughtered a kitten for taking the time to continue reading. While the original posters residence in Sweden grants him SOME immunity from criticism on proper English and syntax, the overwhelming amount of stupidity put into this work is clearly observable with a brief scan of the naked eye.
The only legitimacy I can grant to such an atrocious thread is that its title accurately summarizes the lack of essence to be found on Higgs particle research and actually correlates to what is actually being discussed. But for those of us such as myself who blindly click on anything scientific within TL, this thread becomes entrapment: assuring us that an enlightening wealth of information will be found only to become squandered and a joke.
ahaha, well played.
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On October 13 2011 14:38 Faerie wrote:
I voted no Higgs. God damn freelodaing particle physiscist asking us to build huge accelerators for them on a hunch. Inventing a particle so your reasearch avoids a dead end and trusting to the rest of the stupid community to just suck it up. "Oh yes there is this ghost particle you see....I can haz 10 billion euros to build big accelerator plx.....kk?" We want every penny back Cascade, you hear us? Every penny!
Also, good writeup.
ohai!
we refer to it as creative fund raising.
I guess they will at some point realize that there is no "higgs-bomb" coming out from particle physics anytime soon and start cutting funds. :o Atm Im seeing it as sucking out as much money as we can, then run!!
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I think you could explain better the CL graph, it is the most interesting thing o the article (and the only thing that lets people understand how is made physical research)
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nice interesting read, thanks!
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On October 13 2011 19:35 rubio91 wrote:
I think you could explain better the CL graph, it is the most interesting thing o the article (and the only thing that lets people understand how is made physical research)
Agree, edited. Like that better?
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I can see it! My bet is on 250 GeV. Bur probably you will find 2 and then you have to rethink everything anyways
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Fantasmic article
Q:
Why is LHC taking so long. What's the constraint(s) that stop(s) it from figuring out if it exists in a shorter time scale?
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I did not see the article before the addition of the "science spoilers", so i cannot have an opinion about the original one. Perhaps it was actually without significant context, but mr. Toaster's response had a... hostile attitude at best.
The OP tries to cross the line where a scientific explanation is accessible for the "masses" and goes into a more "you have to have some solid physics/chemistry understanding, in order to read that" approach.
Criticism
+ Show Spoiler +Keeping that in mind, I have to also agree with precious posters (and Toaster) who said that the analogies and the jokes were... kinda out of place. Theese jokes will not make someone who does not have any interest in particle physics read an article on that subject. (BTW i liked the irony of the TL;DR)
Praise
+ Show Spoiler +Now, for a person who has studied science this article can be VERY insightful. It bridges the gap between a hard scientific paper (whoose target audience is scientists of the same field) and of standard popularised articles (whoose target audience is someone without any knowledge of the field at all). For me (undergrad in chemistry, have studied quite a bit of quantum mechanics) it just hit the sweeeeeeeeet spot. It really provided information about the situation (with some explanation behind it), while not demanding extreme knowledge about the subject.
The OP put a great effort in writing this thing, that only a few of TLers will care to read. Yet, those of us who DO care, owe a huge thanks to Cascade for it.
Perhaps some awesome TLers with a degree in a science can do the same thing. Create a post about a subject of their field and try to explain it to fellow scientists of other fields (or other people who really want to learn something) in a non oversimplified fashion. It would be nice if we managed to create a movement of knowledge spreading. (So we would love to see more of some Cascade posting)
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On October 13 2011 20:12 arbitrageur wrote:
Fantasmic article
Q:
Why is LHC taking so long. What's the constraint(s) that stop(s) it from figuring out if it exists in a shorter time scale?
A: It is because of the protons the collide being a mess to disentangle. Actually you can get a hint if you read the part about the strong force in the .pdf i edited in just now.
Briefly, it is due to the proton-proton collisions creating A LOT of events that look very much like an event with a higgs. So there is a huge background to the signal in most cases. They record billions and billions of events, and only a few of them actually contains Higgs (if it exists). It is crazy hard to determine, among the billions of events, if some of them actully are Higgs events or not.
An analogy would be looking for a nail in a haystack, where some of the straws look damn similar to nails.
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if YOU had to pick ~115-120, ~157, or ~600+
what would you pick, personally?
edit: where would you invest time into next in an area that still looks optimistic?
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so let me see if I get this straight...
the higgs particle allows the gauge symmetry to exist?
if the higgs particle doesn't exist does that mean that the crazy high accuracy for the experiments mentioned are not really accurate?
im also curious about your educational background!
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Aotearoa39261 Posts
On October 13 2011 14:37 Skarjak wrote:Show nested quote +On October 13 2011 14:21 Robinsa wrote:
Oh god. I just feel empty inside now. Maybe I'm an idiot and people think this is fun but I just read this huge post and it didn't say me anything. That's a feat in it self I guess. Don't worry, he didn't actually explain anything, so it's perfectly normal that you didn't learn anything. The reason the Higgs is necessary is that the particles we observe have different masses. Other than the Higgs, there is nothing that would explain why particles containing the same number of quarks would have different masses, or why they even have mass at all. The Higgs give them their masses, and it is the last particle predicted by the standard model of particle physics to have not been detected yet, mainly because it requires very energetic collisions to produce these. That's why the LHC was necessary. The standard model is what we use in microscopic physics. It allows for the existence of many particles and has been, generally, a huge success. If somehow, the Higgs does not exist, then there is something fundamentally wrong with the standard model. That would be a major revelation for all physicists and would likely lead us to make huge progress. In fact, finding the Higgs might almost be a bad thing, since it might very well confirm the standard model without teaching us anything. I am personally hoping we don't find it.
This is exactly what several physics profs have told me as well. They all hope that we dont find it so partical physics profs still have a research job lol
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One principle to rule them both, one principle to find them. One principle to write them both, and in the Lagrangian bind them
This made me lol!
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I don't see all this need of the Higgs Boson not existing (and i actually think it exists). Even if we find it there are still so many things to explain/discover etc... just look at the whole Neutrino thing, and it is not the only discovery in recent physics. Finding the Higgs just mean that the SM (standard model) works good, but does not mean it will end our Physics research
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Nice article, nonetheless let me point out:
a)You need to specify the particle conted on the theory as well as the gauge symmetries to define the theory!!
b)There are plenty of higgless electroweak symmetry breaking sector theories which left the rest of the standard model unchanged, for example Technicolor theories have become quite popular lately.
c)The plot you show assumes a model for the higgs sector, which is used to determine the the product particles you look for as a higgs products, however its entirely possible a theory with a light higgs which would led to different decay products to the ones that are being looked for.
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Really enjoyed reading this. Much better than confusing lecturers. Though I feel that a more "known" topic like an introduction to quantum physics would have been a better start than this one. Or E=mc^2, seeing that everyone knew the equation way before they knew what it was for, if they ever found out.
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On October 13 2011 20:56 leo23 wrote:
the higgs particle allows the gauge symmetry to exist?
if the higgs particle doesn't exist does that mean that the crazy high accuracy for the experiments mentioned are not really accurate?
yes on the first. the Higgs stops the symmetry from being broken.
for the accurate descriptions: the equations doing the calculations will hopefully be the same. However, we may have to rethink where the equations come from.
On October 13 2011 21:17 rubio91 wrote:
I don't see all this need of the Higgs Boson not existing (and i actually think it exists). Even if we find it there are still so many things to explain/discover etc... just look at the whole Neutrino thing, and it is not the only discovery in recent physics. Finding the Higgs just mean that the SM (standard model) works good, but does not mean it will end our Physics research
Well, most scientist (at least in my community) believe that the neutrino OPERA measurement is some experimental error. While there are some subtle flaws in the mathematics of the standard model, it would not be easy to use them to motivate another even more expensive accelerator from politicians. So if we find a standard model Higgs and nothing else, itll be tougher to get funding.
On October 13 2011 21:34 HallBregg wrote:
Nice article, nonetheless let me point out:
a)You need to specify the particle conted on the theory as well as the gauge symmetries to define the theory!!
b)There are plenty of higgless electroweak symmetry breaking sector theories which left the rest of the standard model unchanged, for example Technicolor theories have become quite popular lately.
c)The plot you show assumes a model for the higgs sector, which is used to determine the the product particles you look for as a higgs products, however its entirely possible a theory with a light higgs which would led to different decay products to the ones that are being looked for.
a) what i tried to say is with the matter particles decided (given fermionic sector) and fixed gauge groups, the force carriers (bosonic sector) comes out from gauge symmetry. except the W and Z mass. Ill have a look at what i wrote and see if i need to clarify.
b) Yes, there are plenty of BSM models that can take care of that. Plenty of BSM that can take care of any scenario i feel? Probably is a set of SUSY parameters that would explain elefants suddenly jumping out of the collisions. My point is: if we dont see any higgs, and nothing else either at LHC, it is hard to tell which one of the BSMs to go for. Im not a BSM expert though, so feel free to tell us a bit more.
c) yes, im talking about the SM higgs, ill add that to the OP, thanks. Im trying to cover the BSM possibilities in the "no higgs" section.
Anyways, i feel that this last discussion is a bit over the heads of most in this forum, i'd like to keep it understandable without a master in particle physics.
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On October 13 2011 21:46 CloudCat wrote:Really enjoyed reading this. Much better than confusing lecturers. Though I feel that a more "known" topic like an introduction to quantum physics would have been a better start than this one. Or E=mc^2, seeing that everyone knew the equation way before they knew what it was for, if they ever found out.
have a look at the .pdf at the top of the OP. it goes through the history of quantum mechanics to some extent.
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On October 13 2011 10:21 JeeJee wrote:
All I got from this is that we're looking for the higgs boson because we're expecting it in our magical equation for the world, and we expect to have the results within a year.
Can that get any more vague?
I'm not a physicist by any means, actually a math major, but here's what I think he was saying. Physics has a model ("magical equation") that can predict with a very high accuracy experimental results. However, for this model to work the equations must account for there being a HB which up until this point we have not been able to observe. Because of how accurate the model predicts results we trust the model and are now looking for the HB. As far as I know this happens a lot in Physics (and probably other fields as well), a lot of Einsteins equations pertaining to relativity were able to accurately predict things that were not yet observable with scientific tools of the time.
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Very nice write up.
I didn't get starcraft jokes, but dawg was great.
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On October 13 2011 18:35 SgtCoDFish wrote:Show nested quote +On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
Can you at least verify if the statement that we'll "know in a year" if the Higgs exists or not is true? Are there any sites/articles you can recommend to us to find out more on the topic?
Just with all scientific matters it's really not a question of "when" a development will emerge, but "if" they will emerge. Even if the Higgs particle supports and coincides with the entire Standard Model, it still exists only in theory. But purely based on LHCs progress, predictions are still hard to make. The LHC was inaugurated in 2008, but it only recently started to run unreplicated experiments around about a year ago. And advancements already claimed to have been "made" on the Higgs particle are still based on statistical speculation, such as its mass-energy composition. So basically the answer is "Who really knows?"
Regarding sites that yield good info on the LHC, I would actually recommend CERNs homepage for the laboratory itself: http://public.web.cern.ch/public/en/lhc/LHC-en.html
The site does a good job of explaining the technology equipped at different collider experiments without going into mind-numbing detail. Like the original post said, the events happen so fast that not even thousands upon thousands of individual sensors can capture the entire sequence in its entirety. In addition to that, the amount of digitized information collectible from each event can confuse even the worlds fastest supercomputers (which is why researchers filter out the "unnecessary" data).
The sights info serves to shows how fragile and complex testing really becomes when you deal with such massive energy concentrations. Other than that, generally stay away from articles written by mass media such as the New York Times: their focus lies on gaining readers within the general population, which can oversimplify a huge amount of material and turn decades of dedicated research into flashy bullshit similar to what's found in this thread.
But I do have to somewhat apologize for the amount of denouncing I did in my last post. You can't expect perfectly formal and proper scientific thought from a site dedicated to gaming. After all, such content has to be placed under a "general" tab due to its irrelevance to pro gaming itself.
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On October 14 2011 09:43 TheToaster wrote:Show nested quote +On October 13 2011 18:35 SgtCoDFish wrote:On October 13 2011 15:11 TheToaster wrote:
After just recently writing a research paper on the LHC and its search for the Higgs particle, I can unhesitantly state that this article provides almost no informative or insightful thought even on the most basic of scientific developments. At best, this thread proves comical humor on extremely distant yet still SLIGHTLY relative topics within the field of Physics. The analogies are horribly developed, information on the Higgs particle itself exists as barren scraps not worthy of even mentioning, and the irrelevant formatting/imaging clearly consumed more time to develop than if you were to actually WRITE on the Higgs particle.
Can you at least verify if the statement that we'll "know in a year" if the Higgs exists or not is true? Are there any sites/articles you can recommend to us to find out more on the topic? So basically the answer is "Who really knows?"
(sorry for pulling a quote out of context.)
Ofc, we will never be 100% sure of anything ("I think, therefore I exist. I guess."), but if the LHC continues to take statistics as it is doing currently, it will find the standard model Higgs if there is one, by the end of next year. With at least 5 sigma significance, which is like 99.99% probability or something.
I realise that this is amounting to "do not!" "do to!", so here are the slides from the ATLAS presentation on a conference in japan 2 weeks ago that I attended:
EDIT (link removed): on second though I want to check with some ATLAS friend before giving you the link, brb soon, sorry. EDIT2 (link repalces): ok got green light. they are public. hf.
https://indico.cern.ch/materialDisplay.py?contribId=72&sessionId=14&materialId=slides&confId=149305
(I think the slides are public, dont remember if i needed a password for them... well if they dont open for you, I guess they are confidential until the proceedings are out, and i shouldnt be giving them to you anyways. Ill find some older talk at that point.)
feel free to look through all slides, but specially at page 14 which is the same plot as in the OP, but with the lower imit 146GeV, and page 15, where it says at the bottom that a standard model higgs will be found by the end of 2012.
If it is not found by then (all the mass range will be exluded) that is a sign that we need more than just the standard model. "BSM" Beyond Standard Model. Exactly what BSM model, we do not know (unless we see some BSM signal next year), but I'm sure a lot of people will be happy to try to find out.
You are absolutelety correct that this a crazy difficult measurement, but they have a lot of people working on it, and this is also the reason there are TWO independent detectors (ATLAS and CMS) both looking for Higgs. The corresponding plot from CMS looks very similar, which is a sign that things are in order. It is tricky, but these guys are really smart and really know what they are doing. It is not like Dustin Browder trying to create a balanced game. Feel free to look through the slides to get a feel for how they approach it, and I'll be happy to answer questions if things are unclear. I'm not an experimentalist, but I think i can explain most of their methods at least at a basic level.
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lol your introduction is so similar to Sheldon teaching penny physics in Big Bang Theory.
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Sorry for necroing, but today should be an important day in getting closer to an answer of if the Higgs-boson exist or doesn't.
Tomorrow the European Organization for Nuclear Research, more commonly known as CERN, will reveal something about the Higgs boson. Back-to-back public seminars are scheduled for 2 p.m. Zurich time (8 a.m. Eastern) on Wednesday, Dec. 13, each from one of the main ongoing experiments at the Large Hadron Collider (LHC), CERN’s colossal, headline-grabbing atom smasher. And yes, Big Bang Theory fans, you can watch them live.
Also known as the so-called “God particle,” the Higgs boson is one of the most important particles in physics, since it’s responsible for creating mass itself. There’s just one problem: It might not exist. Although science said it should, so far no experiment has shown any sign of the elusive particle.
The science world has been buzzing with rumors about the Higgs boson in the past few weeks after details about tomorrow’s agenda leaked out. From what various physics sites have published, the seminars are expected to reveal strong signs of the Higgs boson particle, but not with enough certainty to call it a bona fide discovery.
That makes sense, since the LHC wasn’t expected to catch sight of the Higgs since it still hasn’t powered up to its full capacity yet (it’s running at about half energy). CERN Director General Rolf-Dieter Heuer told Canada’s National Post he expected the final word on the existence of the Higgs to come by October 2013.
You can watch the lecture live from CERN’s webcast here. Once the announcement is public, you can discuss it with other physics enthusiasts at CERN’s Facebook page. The blog Quantum Diaries is hosting a liveblog of the even. And, of course, you can read the news on Mashable.
source
it was released yesterday. There is about 1 hour till the public seminar!
Watch it live here!
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On December 13 2011 21:00 radiatoren wrote:Sorry for necroing, but today should be an important day in getting closer to an answer of if the Higgs-boson exist or doesn't. Show nested quote +Tomorrow the European Organization for Nuclear Research, more commonly known as CERN, will reveal something about the Higgs boson. Back-to-back public seminars are scheduled for 2 p.m. Zurich time (8 a.m. Eastern) on Wednesday, Dec. 13, each from one of the main ongoing experiments at the Large Hadron Collider (LHC), CERN’s colossal, headline-grabbing atom smasher. And yes, Big Bang Theory fans, you can watch them live.
Also known as the so-called “God particle,” the Higgs boson is one of the most important particles in physics, since it’s responsible for creating mass itself. There’s just one problem: It might not exist. Although science said it should, so far no experiment has shown any sign of the elusive particle.
The science world has been buzzing with rumors about the Higgs boson in the past few weeks after details about tomorrow’s agenda leaked out. From what various physics sites have published, the seminars are expected to reveal strong signs of the Higgs boson particle, but not with enough certainty to call it a bona fide discovery.
That makes sense, since the LHC wasn’t expected to catch sight of the Higgs since it still hasn’t powered up to its full capacity yet (it’s running at about half energy). CERN Director General Rolf-Dieter Heuer told Canada’s National Post he expected the final word on the existence of the Higgs to come by October 2013.
You can watch the lecture live from CERN’s webcast here. Once the announcement is public, you can discuss it with other physics enthusiasts at CERN’s Facebook page. The blog Quantum Diaries is hosting a liveblog of the even. And, of course, you can read the news on Mashable. sourceit was released yesterday. There is about 1 hour till the public seminar! Watch it live here!
What a righteous necro! Totally watching this when it comes on. Good find!
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Great writeup. Although I wish there was a better way to explain physics.
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On December 13 2011 21:00 radiatoren wrote:Sorry for necroing, but today should be an important day in getting closer to an answer of if the Higgs-boson exist or doesn't. Show nested quote +Tomorrow the European Organization for Nuclear Research, more commonly known as CERN, will reveal something about the Higgs boson. Back-to-back public seminars are scheduled for 2 p.m. Zurich time (8 a.m. Eastern) on Wednesday, Dec. 13, each from one of the main ongoing experiments at the Large Hadron Collider (LHC), CERN’s colossal, headline-grabbing atom smasher. And yes, Big Bang Theory fans, you can watch them live.
Also known as the so-called “God particle,” the Higgs boson is one of the most important particles in physics, since it’s responsible for creating mass itself. There’s just one problem: It might not exist. Although science said it should, so far no experiment has shown any sign of the elusive particle.
The science world has been buzzing with rumors about the Higgs boson in the past few weeks after details about tomorrow’s agenda leaked out. From what various physics sites have published, the seminars are expected to reveal strong signs of the Higgs boson particle, but not with enough certainty to call it a bona fide discovery.
That makes sense, since the LHC wasn’t expected to catch sight of the Higgs since it still hasn’t powered up to its full capacity yet (it’s running at about half energy). CERN Director General Rolf-Dieter Heuer told Canada’s National Post he expected the final word on the existence of the Higgs to come by October 2013.
You can watch the lecture live from CERN’s webcast here. Once the announcement is public, you can discuss it with other physics enthusiasts at CERN’s Facebook page. The blog Quantum Diaries is hosting a liveblog of the even. And, of course, you can read the news on Mashable. sourceit was released yesterday. There is about 1 hour till the public seminar! Watch it live here!
I saw this as well, will be interested to see what they say.
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omg, I'm actually nervous This is so cool. A huge discovery if they have found the higgs particle!
Almost as cool as the particle traveling faster than light.
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OMG they are so desperate. 1.5 sigma excess? WHAT? Wasn't that CERN who pressed that anything under 5 sigma should be neglected? (and even then, it does not have to mean anything, pentaquarks were once observed with a qutote 7 sigma confidence. Does anyone today believe in pentaquarks? No.) So far this seminar looks more overhyped than Stephano!
edit: OK, the combined result is slightly better but still. This really should not be hyped liked this.
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Pretty strong signal for a SM Higgs at 126 GeV.
Like a bit above 95% certaintly depending on how you look at it as I understand. Global 2.4 sigma significance.
*Cautiously optimistic*
edit: got wrong percentage, so many numbers in the presentation..
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On December 13 2011 22:36 opisska wrote:
OMG they are so desperate. 1.5 sigma excess? WHAT? Wasn't that CERN who pressed that anything under 5 sigma should be neglected? (and even then, it does not have to mean anything, pentaquarks were once observed with a qutote 7 sigma confidence. Does anyone today believe in pentaquarks? No.) So far this seminar looks more overhyped than Stephano!
edit: OK, the combined result is slightly better but still. This really should not be hyped liked this.
Edit: Never mind, I completely brainfarted.
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On December 13 2011 22:49 Cascade wrote:Pretty strong signal for a SM Higgs at 126 GeV. Like a bit above 95% certaintly depending on how you look at it as I understand. Global 2.4 sigma significance. *Cautiously optimistic* edit: got wrong percentage, so many numbers in the presentation..
This is anything but a "pretty strong signal". In any other enviroment, the speaker would be laughed at after the kind of presentation we have just seen from the ATLAS spokesperson. If I came to my boss with an intention to show somethink like this on a public seminar, I would probalby be fired
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It's not their fault the "science journalists" there can't understand anything. If the articles in the media would reflect what's actually being said there wouldn't be much of an issue.
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On December 13 2011 22:59 opisska wrote:Show nested quote +On December 13 2011 22:49 Cascade wrote:Pretty strong signal for a SM Higgs at 126 GeV. Like a bit above 95% certaintly depending on how you look at it as I understand. Global 2.4 sigma significance. *Cautiously optimistic* edit: got wrong percentage, so many numbers in the presentation.. This is anything but a "pretty strong signal". In any other enviroment, the speaker would be laughed at after the kind of presentation we have just seen from the ATLAS spokesperson. If I came to my boss with an intention to show somethink like this on a public seminar, I would probalby be fired
haha, fair enough. What I meant was "given the situation (statistics etc), it's a pretty strong signal". I didn't expect this strong signal until summer next year, so compared to my expectations, it is a large signal.
The official statement that came with it is "still no conclusive evidence for Higgs", which is absolutely true. Still, it's 2.4 sigma globally!! 3.6 locally!! HIIGGGGGSSSSS!!! :D
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On December 13 2011 22:36 opisska wrote:
OMG they are so desperate. 1.5 sigma excess? WHAT? Wasn't that CERN who pressed that anything under 5 sigma should be neglected? (and even then, it does not have to mean anything, pentaquarks were once observed with a qutote 7 sigma confidence. Does anyone today believe in pentaquarks? No.) So far this seminar looks more overhyped than Stephano!
edit: OK, the combined result is slightly better but still. This really should not be hyped liked this.
They're not that hyped. It's mostly the media that's hyping it up. CERN is just doing an end-of-year seminar with an update on the results. Yeah, there are good indications of a Higgs boson at 126 GeV, but it's hardly conclusive. This is the first year where there's a real body of data from LHC to actually analyze. At the end of last year, the amount of data available was many times less as the engineers were still working on improving the collision rate in the detectors. So in that sense it's the first glimpse into the results. That's what makes it an interesting seminar.
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If you did not think that the ATLAS presenation is pathetic, be sure to watch CMS now
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At the very least, it gives a specific target to aim for while they continue the search.
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On December 13 2011 23:08 Rannasha wrote:Show nested quote +On December 13 2011 22:36 opisska wrote:
OMG they are so desperate. 1.5 sigma excess? WHAT? Wasn't that CERN who pressed that anything under 5 sigma should be neglected? (and even then, it does not have to mean anything, pentaquarks were once observed with a qutote 7 sigma confidence. Does anyone today believe in pentaquarks? No.) So far this seminar looks more overhyped than Stephano!
edit: OK, the combined result is slightly better but still. This really should not be hyped liked this. They're not that hyped. It's mostly the media that's hyping it up. CERN is just doing an end-of-year seminar with an update on the results. Yeah, there are good indications of a Higgs boson at 126 GeV, but it's hardly conclusive. This is the first year where there's a real body of data from LHC to actually analyze. At the end of last year, the amount of data available was many times less as the engineers were still working on improving the collision rate in the detectors. So in that sense it's the first glimpse into the results. That's what makes it an interesting seminar.
So FTL Neutrinos and some evidence for the Higgs. Quite a good run for the year.
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And CERN dodges again. ._.
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On December 14 2011 01:24 Mortal wrote:
And CERN dodges again. ._.
Dodges what? They give clear and detailed information on the state of the Higgs search. Numbers and error-analyses included. I found the information they provided quite interesting. But the whole seminar they held this afternoon wasn't meant for the general public, it was meant for other scientists, mostly from within CERN, so they could be kept up-to-date on the progress of the search.
If you're looking for flashy one-liners, you should pick up a local tabloid rather than looking at official scientific reports.
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So in spring there is going to be another test to finalize the findings?
As a note... even though I know the word "God Particle" is controversial, if it was put in the thread title it would attract a lot more attention to this thread. This is something people should be discussing. Only 4 pages is insulting.
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Here's a little update on the hunt:
http://www.bbc.co.uk/news/science-environment-17269647
Scientists from the US Tevatron accelerator say they have spotted possible hints of the Higgs boson at a mass similar to that seen at the LHC.
The findings add weight to the idea that the Higgs - purported to give all other particles their mass - exists near a mass of 125 gigaelectronvolts.
However, the new data are not themselves sufficiently statistically assured to rate the find a "discovery".
The results were presented at the Moriond physics conference in Italy.
The Tevatron, based at the US national laboratory Fermilab, was for two decades the world's premier particle accelerator, but was shut down in 2011 after negotiations to extend funding failed.
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Statistics of a 'discovery'
Quarter
Particle physics has an accepted definition for a "discovery": a five-sigma level of certainty
The number of standard deviations, or sigmas, is a measure of how unlikely it is that an experimental result is simply down to chance rather than a real effect
Similarly, tossing a coin and getting a number of heads in a row may just be chance, rather than a sign of a "loaded" coin
The "three sigma" level represents about the same likelihood as tossing more than eight heads in a row
Five sigma, on the other hand, would correspond to tossing more than 20 in a row
With independent confirmation by other experiments, five-sigma findings become accepted discoveries
However, like all particle-smashers, the Tevatron created a tremendous amount of data that remained to be analysed.
The latest data hint at the existence of a particle between 115 and 135 gigaelectronvolts (GeV; this is between about 120 and 140 times as heavy as the protons found in every atom) with a certainty of about 2.2 sigma.
That means that there is about a one in 36 chance that the anomaly they see is the result of happenstance - far less assured than the "five sigma" threshold that physicists use to demarcate a formal discovery.
However, what makes the find more compelling is that the Large Hadron Collider has found a suggestive "bump" in its data at about the same mass, despite being a radically different experiment.
The LHC collides protons together, while the Tevatron used protons and their antimatter counterpart, antiprotons.
Both experiments hunt for the Higgs by looking at what those high-energy particles decay into.
At the Tevatron, the data are from the production of bottom quarks and their counterparts bottom antiquarks, whereas at the LHC the primary search is for the production of the light particles known as photons.
"It's a different accelerator, different detectors and a different decay channel," said Rob Roser, spokesman for CDF, one of the two main Tevatron detectors.
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What is an electronvolt?
Particle interaction simulation (SPL)
Charged particles tend to speed up in an electric field, defined as an electric potential - or voltage - spread over a distance
One electronvolt (eV) is the energy gained by a single electron as it accelerates through a potential of one volt
It is a convenient unit of measure for particle accelerators, which speed particles up through much higher electric potentials
But because of the equivalence of mass and energy laid out in E=MC2, physicists also speak of the mass of particles in electronvolts
"It adds to the picture, and it's starting to make a compelling case," he told BBC News. "But we can't make quite as bold a statement as we would like.
"I just wish either one of us just had more data right now. It's frustrating."
The two main detectors at the LHC, CMS and Atlas, also presented results at the meeting on Wednesday, but the experiments have precious little further data relative to those presented late last year.
That will radically change later this year as the facility will produce three times the amount of data this year as in 2011.
However, recent analysis of Atlas data has "excluded" the mass range up to 122.5 GeV. The Tevatron data, meanwhile, exclude its presence at the heavier masses of 147-179 GeV, also completely consistent with what the LHC has found.
As has been said before, if it indeed exists, there are few places left for the Higgs boson to hide.
Tony Weidberg, a University of Oxford physicist who works at the LHC's Atlas detector, said that the Tevatron results were consistent with the idea of a comparatively "light" Higgs boson.
"It's interesting because it's another little hint," Dr Weidberg told BBC News. "It makes it a little bit more likely that we're going to end the year with a discovery rather than an exclusion.
"The proof of the pudding will be in the LHC data that we'll get this year; by the end of the year we'll have moved away from hints to either discovery or exclusion - and either of those results is exciting to me."
Go Go Tevatron.
Sorry that the quote came out a little jumbled.
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EPT![[image loading]](http://i.imgur.com/5XA14.gif)
