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Comment: Re:More than one Higgs Boson? (Score 5, Informative) 42

by craklyn (#47298157) Attached to: Fresh Evidence Supports Higgs Boson Discovery

This is kind of like if you're walking through the woods and you discover piles of bear shit as you go. The bear shit implies there's at least one bear in the woods, but it does not preclude that there could be multiple bears responsible for it.

The Higgs field is a solution to the question of why some fundamental particles have mass. Theoretically, such a field is well-motivated. If such a field exists, it implies there is at least one massive, spin-zero particle that we have decided to call the Higgs boson. There are various extensions to our models, such as the so-called "Higgs two-doublet model" which SUSY extends, where more than one Higgs exists.

Comment: Re:More than one Higgs Boson? (Score 3, Informative) 42

by craklyn (#47298111) Attached to: Fresh Evidence Supports Higgs Boson Discovery

One cannot measure a Higgs boson directly since it promptly decays. Consequently, it's necessary to identify particles it decays into.

Quarks and leptons are measurable objects in detectors, but quarks and leptons are also created in other processes that are much more likely to occur. This creates a large background which must be subtracted from the Higgs boson decay's signal. These channels are harder to measure due to the significant background.

The other channels of Higgs decay that were identified first included Higgs bosons decaying into gauge bosons. The probability of this occuring is not so large, but such decays can result in 4 leptons (e.g. two electrons plus two muons, four electrons, or four muons), and that has a very clean, measurable signal with very low background.

Comment: Re: Repeat story (Score 1) 238

by craklyn (#46197117) Attached to: CERN Wants a New Particle Collider Three Times Larger Than the LHC
The LHC and its major experiments were built with the goal of discovering the Higgs Boson or excluding it, and it has secondary goals to search for new physics such as SUSY. We built the appropriate machine for accomplishing that goal. If we had the LHC in the 1950's, we would have had a few problems: 1) Astronomical cost to build, 2) Insufficient computational power to analyze the results, and 3) No theoretical framework motivating a search for a scalar particle in a certain mass range. In short, it would be building something too expensive that would be unusable and it would be given to people who wouldn't know what to do with it even if they could use it.

Comment: Re:huh (Score 1) 396

by craklyn (#40549423) Attached to: LHC Discovers New Particle That Looks Like the Higgs Boson

In 2012, it's 8 TeV by the way. Hopefully 14 TeV in 2014.

It's a little more complicated than looking at the total center-of-mass energy and saying we can discovery any particle up to the max. A single proton is made of multiple constituents, and a proton incoming with 3.5 TeV (or 4 or 7) of energy represents the total energy of that system. When two protons interact, it's actually two constituents which are interacting, and they will have some fraction of the proton's energy. So typically the probability of producing particles drops considerably as you look for more massive particles.

That said, the central sentiment of your message is correct. There is a lot of potential signals that remain to be investigated. There could even be particles found with considerably less mass than the Higgs, but which have an unusual decay signature which we haven't been sensitive to yet.

Comment: Re:Now what? (Score 1) 652

by craklyn (#40549373) Attached to: Texas Scientists Regret Loss of Higgs Boson Quest

What happens next is we study this particle. We want to know if it behaves as is predicted by the standard model, or if it's something different from what we expect. This includes measuring its cross section (the probability of it being created in collision) and its branching ratio (the probability of it decaying to each thing its able to decay to).

Matt Strassler (a theoretical physicist) describes the general roadmap in his blog post here.

Particle physics results are necessarily esoteric. What do we do with experimental knowledge? We use this knowledge to disprove plausible theory and to constrain future theory. Theory is similarly used to give direction for new experiments.

Comment: Re:Disruptive Innovation? (Score 3) 325

by craklyn (#37843760) Attached to: Netflix Loses 800,000 Subscribers After Qwikster Gaffe

The innovation is fine. The problem is that Netflix' leadership has been unable to communicate with its customers in an intelligent way. They need to tuck us into bed, and tell a bed time story which ends "and then you bought our new product and lived happily ever after." This is what Apple does when they innovate.

Instead, you can look at the Quickster announcement. First paragraph: "I messed up. I owe everyone an explanation." Second paragraph: Talks about how they treated their customers like idiots by saying that they were lowering prices when the prices increased. Paragraph ten: Announce Qwikster.

Why even combine these two messages into a single product announcement?

Comment: Re:And lose all their normal sports customers? (Score 2) 351

by craklyn (#37193298) Attached to: Sports Bars Changing Channels For Video Gamers
I was present for the opening night in Chao Bistro in Seattle. Their restaurant/bar is already naturally separated into two sections, so they had Starcraft 2 in one section and the normal bar in the other. The bar owners tend to run these events on traditionally slow nights, so there's room for normal patrons and gamer patrons at one time.

Comment: Re:Naive Question (Score 1) 196

by craklyn (#35351226) Attached to: Will the LHC Smash Supersymmetry?

Fundamental science's goal is to understand how the universe we live in behaves. We accumulate evidence about how the universe works (called "measurements"), and use it to rule out incorrect possibilities.

It's the job of others, such as scientists who don't work on fundamental research (called "engineers"), to decide what we can do with the universe we live in.

Comment: Re:Well sure (Score 3, Interesting) 224

by craklyn (#34442536) Attached to: IAEA Forms Nuclear Fuel Bank
According to the World Nuclear Association:

All nuclear reactors, at least in the west, are insured. Not only so, they are a sought-after risk because of their high engineering and operational standards. Beyond the cover for individual plants there are national and international pooling arrangements for comprehensive cover.

Perhaps the World Nuclear Association has some bias or they're refering to something different than you are. It's hard to evaluate that since you don't include a source, though.

Comment: Re:Unlike the "Galaxy sized detector" (Score 0) 109

by craklyn (#32164006) Attached to: Biggest Detector To Look For Gravitational Waves

It's pretty disingenuous to link the cost of a detector to its size, as though size indicates scientific merit.

But maybe I'm just bias because I have studied atoms (0.5x10^-10 meter scale) on a graduate student stipend ($20k per year). This cost my university a measly $400,000,000,000,000 per meter per year.

Comment: Re:Good and bad (Score 1, Insightful) 352

by craklyn (#31933932) Attached to: UK University Researchers Must Make Data Available
For many academic scientists (i.e. professors, post-docs, graduate students), a part of their pay is the ability to publish their research findings. It takes long thought and work to devise and carry out experiments which gather pertinent data. It's not unreasonable to allow some time for these scientists to analyze their data and properly understand it.
If you mandate all data be immediately made public, the researcher can be "scooped" by anyone. This is bad for science because it removes the incentive to actually gather the data. This is one argument for why data may be kept internal, at least for a while.

Comment: Re:Luminosity more important than energy (Score 0) 194

by craklyn (#31020060) Attached to: Europe's LHC To Run At Half-Energy Through 2011

According to my professor (who is very involved in the LHC) the first LHC run will be collecting an integrated luminoscity of 1 fb^-1.

Another professor mentioned today that by the end of the Tevatron's life (in a couple years), it will have collected 12 fb^-1. This is over it's 10-ish year life span.

At this point, some may wonder why the LHC is unable to keep pace with the Tevatron, the old toy. These machines are very complicated, and apparently don't work nearly to maximum efficiency out of the box. Check out this plot of the amount of data collected at the tevatron versus year. The slope is rising continuously, as they improve their beam and detectors to handle more collisions:

Tevatron Integrated Luminosity

"What is wanted is not the will to believe, but the will to find out, which is the exact opposite." -- Bertrand Russell, _Sceptical_Essays_, 1928