bosones

CERN’s at it Again: New Subatomic Particle Discovered at the LHC

CERN just discovered a new subatomic particle called the “pentaquark.” And it offers some interesting insights regarding the nature of, well, nature.

Ten days after the three-year anniversary of CERN’s discovery of the Higgs boson, researchers on the LHCb experiment at CERN have announced that another discovery has been made: They have found a new exotic class of particles.

The team has submitted their findings to the journal Physical Review Letters for reviewal.

These particles are called “pentaquarks,” and they offer some interesting insights regarding the nature of, well, nature. Typically, we find that composite particles consist of three quarks. The proton, for example, is composed of three valence quarks: Two up quarks and a down quark. But in 1964, American physicist Murray Gell-Mann revolutionized our understanding of matter by proposing that baryons and mesons are comprised of quark and antiquark pairs. In essence, Gell-Mann’s quark model allows, in principle, for particles to be made of up to five quarks (hence the prefix, “penta-”).

Pentaquarks are seasoned subatomic celebrities, having had a few moments in the spotlight due to several false alarm “discoveries.”

Researchers at the SPring-8 synchrotron in Harima, Japan claimed to have found a pentaquark in 2002, with several other labs claiming to have found evidence for the pentaquark as well. Because of this, it would be understandable if one was skeptical of CERN’s claims - even CERN was skeptical when the bump first appeared in their data, which prompted researchers to check the data in every way they could.

However, the method by which LHCb experimenters accumulated their data is different from other teams - and more reliable, to boot!

Read more at:
http://bit.ly/1M4CsCL

The Standard Model of particle physics

Explore the elementary particles that make up our universe.

The Standard Model is a kind of periodic table of the elements for particle physics. But instead of listing the chemical elements, it lists the fundamental particles that make up the atoms that make up the chemical elements, along with any other particles that cannot be broken down into any smaller pieces.

The complete Standard Model took a long time to build. Physicist J.J. Thomson discovered the electron in 1897, and scientists at the Large Hadron Collider found the final piece of the puzzle, the Higgs boson, in 2012.

Use this interactive model (based on a design by Walter Murch for the documentary Particle Fever) to explore the different particles that make up the building blocks of our universe.

Launch the interactive model »

THE YARKOVSKY EFFECT

Asteroids are the remnants of the building blocks of our solar system. The Yarkovsky Effect – named for its discoverer Ivan Yarkovsky – is the somewhat obscure mechanism by which an asteroid’s orbit is changed with seemingly no other astronomical bodies interacting with them.

Let’s start with objects in space. Newton’s First Law states simply that a body at rest – for example an object in space, such as an asteroid – stays at rest, and a body in motion stays in motion until it is acted upon by another body. If nothing acts on it, it won’t move.

In 1901, Max Planck explained something called black body radiation. After a series of experiments in Berlin, he concluded that non-reflective matter gives off radiation in discrete amounts when heated. This radiation comes in the form of the electromagnetic spectrum and its carrier gauge boson, the photon. Objects exposed to a little bit of heat give off radiation of very long wavelengths. Living beings, for example, generate their own internal heat which is given off as infrared heat. This radiation is the basis for technology such as night vision goggles. Objects exposed to a lot of heat, such as a steel ingot heated by a fire, give off radiation in much shorter wavelengths. Depending on how hot it gets, it might give off light in the visible wavelengths, and begin to glow red hot. In short, all heated bodies give off photons.

This principle applies to asteroids, as well as all ordinary matter. Heating the sunny side of an asteroid causes it to give off minute but nonzero numbers of photons, and according to Newton’s Third Law any force exerted by one body on another has an equal reaction in the opposite direction.

Take for example an asteroid that is rotating in space as it orbits the sun. Asteroids can rotate in one of two directions: prograde or retrograde. On the surface of a prograde rotator, sunset is in the direction away from its orbital movement. The side of the asteroid that has been heating all day is now faced away from its direction of orbit and emits photons away from its direction of movement. According to Newton’s Third Law, the asteroid gets a small kick from the emission of these photons and speeds up, moving farther from the sun.

The opposite is true for a retrograde rotator. On the surface of a retrograde rotator, sunset is in the direction of its orbital movement. The side of the asteroid that has been heating all day is now faced toward its direction of orbit and emits photons toward its direction of movement. In this case, Newton’s Third Law acts like the break of an automobile or bicycle, and the asteroid slows down and spirals towards the sun.

Regardless of its direction of rotation, this effect builds over time.
The Yarkovsky Effect was confirmed by observing asteroid RQ36, also known as Bennu, from 1999 to 2011 using the Aricebo radio telescope in Puerto Rico and the Goldstone radio telescope in California. The asteroid is the target of the planned 2016 Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer (OSIRIS-REx) space probe mission. For OSIRIS-REx to rendezvous with RQ36 a precise understanding of the asteroid’s orbit is required. RQ36 was observed for 12 years, and at the end of that period it was 160 kilometers past where it would have been predicted to be in its orbit had the Yarkovsky effect not been acting upon it. - MAX

FURTHER READING: 1, 2, 3

PHOTO CREDIT:
By NASA/JPL-Caltech (x) [Public domain], via Wikimedia Commons

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Higgs Boson Blues by Nick Cave & The Bad Seeds

This kind of descriptions appear to arrive from the land in between intense theoretical physics and bare esotericism. The early eighties, the string concept has currently been created, it is nonetheless an unproven concept, absolutely nothing much more. But that could quickly alter. In the U.S. journal “Bodily Evaluation Letters” (No. ninety eight, Vol five, 051301) Shiu and his colleague Bret Underwood printed a publish with the pluck to communicate at the suggestion of string concept: They produced a route prior to, tracked with the additional proportions and their designs can be illustrated by way of pc simulation. To do so, Gary Shiu, the cosmic clock, nevertheless, flip back again extremely much - and up to the time when the globe just ten-forty three seconds previous (Planck time) and only ten-35 ft tall (Planck size) was. Simply because prior to the area in the so-known as inflationary stage inside a Quintillionstel (a quantity with thirty zeros) 2nd 1029aufblГ¤hte with extraordinary energy by the gigantic aspect, cavorting in him might have other proportions: what string theorists forecast - and desires to find Shiu. Time to lookup for additional proportions “Our concept was to go back again in time and see what truly occurred back again then was,” Shiu informed SPIEGEL On-line. Much more than thirteen.three billion many years into the previous, the historian of the universe can not neglect, nevertheless, as only this time the universe was awesome sufficient to produce atoms, and therefore mild. In 2003, the NASA probe “Wilkinson Microwave Anisotropy Probe” (WMAP) shot a 360-diploma map of the microwave track record radiation that is still left from that time - a fingerprint of the Large Bang. It is the oldest and sharpest picture from prehistoric occasions our universe in which a lot info is frozen. Exactly where, if not right here, even references to the existence of extra proportions ought to be integrated? Lastly, was the affect of the 6 small proportions instantly following the large bang the greatest - and could have an influence on the quantifiable for the individuals of the mass distribution in the universe. “Just as the shadow provides a clue to the form of an item, the sample of cosmic rays can in the form of the other 6 proportions stage,” states Shiu. But which traces the WMAP Panoramic they ought to appear? The scientists experimented with two various kinds of mathematically easy geometries. How would these proportions impact the power distribution in area? She visualized on a pc card. Then, when evaluating the fictional map with the WMAP authentic Shiu and Underwood discovered little but substantial variations. On the pc-produced illustration, these are in the type of little, patch-like shades, which stage to a extremely various temperature and power distribution. With much better resolution: Shadow of additional proportions Following each researchers give these unique radiation sample distinct indications of the geometry of the 6-dimensional form. “Our outcomes display that the geometry of concealed proportions can be decrypted by the designs of cosmic power,” states Shiu. “This is a uncommon chance to check string concept.” But scientists require to finer information than these of the WMAP measurements. Now they hope the new extremely delicate Esa Area Telescope “Planck”, which can detect temperature variations of even a 5-millionths of a diploma Celsius. “‘Planck’ will be in a position to evaluate the cosmic track record radiation with extraordinary precision,” states Shiu. “Till lately, concealed proportions had been nonetheless regarded as to be completely inaccessible. Now but there are currently a number of suggestions and situations, how they can be tracked.” “On the concept of Shiu and Underwood some thing may be off,” the Munich astrophysicist Harald Lesch informed SPIEGEL On-line. “It is just only the query of the extent to which the spatial traits are mirrored in the cosmic track record radiation, when the universe was only ten-35Meter fantastic.” Beginning subsequent yr, this query could be answered. Then the extremely delicate probe is introduced into area - and the string concept lastly comes on the cosmic check.

This sort of descriptions look to appear from the land among severe theoretical physics and bare esotericism. The early eighties, the string thought has presently been produced, it is nevertheless an unproven principle, nothing at all a lot more. But that could shortly modify. In the U.S. journal “Actual physical Assessment Letters” (No. 98, Vol 5, 051301) Shiu and his colleague Bret Underwood revealed a submit with the pluck to talk at the idea of string principle: They created a path just before, tracked with the added dimensions and their styles can be illustrated through personal computer simulation. To do so, Gary Shiu, the cosmic clock, nonetheless, change again really significantly - and up to the time when the planet just 10-43 seconds outdated (Planck time) and only 10-35 toes tall (Planck duration) was. Since just before the room in the so-referred to as inflationary period inside of a Quintillionstel (a amount with 30 zeros) next 1029aufblГ¤hte with amazing electrical power by the gigantic element, cavorting in him could have other dimensions: what string theorists predict - and needs to track down Shiu. Time to research for added dimensions “Our thought was to go again in time and see what actually took place again then was,” Shiu advised SPIEGEL On the internet. A lot more than 13.3 billion a long time into the earlier, the historian of the universe can not forget about, nonetheless, as only this time the universe was great adequate to create atoms, and hence gentle. In 2003, the NASA probe “Wilkinson Microwave Anisotropy Probe” (WMAP) shot a 360-degree map of the microwave qualifications radiation that is remaining from that time - a fingerprint of the Huge Bang. It is the oldest and sharpest impression from prehistoric instances our universe in which significantly details is frozen. In which, if not listed here, even references to the existence of further dimensions must be incorporated? Ultimately, was the impact of the six little dimensions right away right after the huge bang the largest - and could have an effect on the quantifiable for the folks of the mass distribution in the universe. “Just as the shadow offers a clue to the condition of an object, the pattern of cosmic rays can in the condition of the other six dimensions level,” claims Shiu. But which traces the WMAP Panoramic they must search? The researchers experimented with two distinct varieties of mathematically straightforward geometries. How would these dimensions have an effect on the vitality distribution in room? She visualized on a personal computer card. Then, when comparing the fictional map with the WMAP unique Shiu and Underwood identified tiny but considerable distinctions. On the personal computer-created representation, these are in the kind of tiny, patch-like shades, which level to a really distinct temperature and vitality distribution. With far better resolution: Shadow of added dimensions Right after the two experts give these particular radiation pattern very clear indications of the geometry of the six-dimensional condition. “Our final results present that the geometry of hidden dimensions can be decrypted by the styles of cosmic vitality,” claims Shiu. “This is a unusual possibility to examination string principle.” But researchers want to finer info than individuals of the WMAP measurements. Now they hope the new very sensitive Esa Room Telescope “Planck”, which can detect temperature distinctions of even a five-millionths of a degree Celsius. “‘Planck’ will be capable to measure the cosmic qualifications radiation with remarkable precision,” claims Shiu. “Until finally not too long ago, hidden dimensions have been nevertheless deemed to be entirely inaccessible. Now but there are presently numerous tips and eventualities, how they can be tracked.” “On the principle of Shiu and Underwood one thing may well be off,” the Munich astrophysicist Harald Lesch advised SPIEGEL On the internet. “It really is just only the issue of the extent to which the spatial qualities are reflected in the cosmic qualifications radiation, when the universe was only 10-35Meter excellent.” Commencing up coming 12 months, this issue could be answered. Then the very sensitive probe is released into room - and the string principle ultimately arrives on the cosmic examination.

This sort of descriptions look to appear from the land among severe theoretical physics and bare esotericism. The early eighties, the string thought has presently been produced, it is nevertheless an unproven principle, nothing at all a lot more. But that could shortly modify. In the U.S. journal “Actual physical Assessment Letters” (No. 98, Vol 5, 051301) Shiu and his colleague Bret Underwood revealed a submit with the pluck to talk at the idea of string principle: They created a path just before, tracked with the added dimensions and their styles can be illustrated through personal computer simulation. To do so, Gary Shiu, the cosmic clock, nonetheless, change again really significantly - and up to the time when the planet just 10-43 seconds outdated (Planck time) and only 10-35 toes tall (Planck duration) was. Since just before the room in the so-referred to as inflationary period inside of a Quintillionstel (a amount with 30 zeros) next 1029aufblГ¤hte with amazing electrical power by the gigantic element, cavorting in him could have other dimensions: what string theorists predict - and needs to track down Shiu. Time to research for added dimensions “Our thought was to go again in time and see what actually took place again then was,” Shiu advised SPIEGEL On the internet. A lot more than 13.3 billion a long time into the earlier, the historian of the universe can not forget about, nonetheless, as only this time the universe was great adequate to create atoms, and hence gentle. In 2003, the NASA probe “Wilkinson Microwave Anisotropy Probe” (WMAP) shot a 360-degree map of the microwave qualifications radiation that is remaining from that time - a fingerprint of the Huge Bang. It is the oldest and sharpest impression from prehistoric instances our universe in which significantly details is frozen. In which, if not listed here, even references to the existence of further dimensions must be incorporated? Ultimately, was the impact of the six little dimensions right away right after the huge bang the largest - and could have an effect on the quantifiable for the folks of the mass distribution in the universe. “Just as the shadow offers a clue to the condition of an object, the pattern of cosmic rays can in the condition of the other six dimensions level,” claims Shiu. But which traces the WMAP Panoramic they must search? The researchers experimented with two distinct varieties of mathematically straightforward geometries. How would these dimensions have an effect on the vitality distribution in room? She visualized on a personal computer card. Then, when comparing the fictional map with the WMAP unique Shiu and Underwood identified tiny but considerable distinctions. On the personal computer-created representation, these are in the kind of tiny, patch-like shades, which level to a really distinct temperature and vitality distribution. With far better resolution: Shadow of added dimensions Right after the two experts give these particular radiation pattern very clear indications of the geometry of the six-dimensional condition. “Our final results present that the geometry of hidden dimensions can be decrypted by the styles of cosmic vitality,” claims Shiu. “This is a unusual possibility to examination string principle.” But researchers want to finer info than individuals of the WMAP measurements. Now they hope the new very sensitive Esa Room Telescope “Planck”, which can detect temperature distinctions of even a five-millionths of a degree Celsius. “‘Planck’ will be capable to measure the cosmic qualifications radiation with remarkable precision,” claims Shiu. “Until finally not too long ago, hidden dimensions have been nevertheless deemed to be entirely inaccessible. Now but there are presently numerous tips and eventualities, how they can be tracked.” “On the principle of Shiu and Underwood one thing may well be off,” the Munich astrophysicist Harald Lesch advised SPIEGEL On the internet. “It really is just only the issue of the extent to which the spatial qualities are reflected in the cosmic qualifications radiation, when the universe was only 10-35Meter excellent.” Commencing up coming 12 months, this issue could be answered. Then the very sensitive probe is released into room - and the string principle ultimately arrives on the cosmic examination.

bringing me your demons

your voice riffles through the air
stretched through time’s hipster
boldly
kissing nature’s magnetic fields
and
the allusive curvatures of space,
self-serving leptons, and bosons -

the auric counsel of demons
arrive on time
stepping into
my
modern
dreams …

you stayed with them
to ram your scripture
into
me ..

demons
demons … lurking everywhere …

the
howls
of your soul … somewhere in a chamber
where
the eerie grin of your echoes calls them
demon-friends -

… and the night
has gone hyperbolic
with the pistachio moon
and her earnest shadows
creeping into me with finesse
marching in my interior landscape …
with your name written on their cloaks …

The Standard Model of Particle Physics

The Standard Model is a kind of periodic table of the elements for particle physics. But instead of listing the chemical elements, it lists the fundamental particles that make up the atoms that make up the chemical elements, along with any other particles that cannot be broken down into any smaller pieces.

The complete Standard Model took a long time to build. Physicist J.J. Thomson discovered the electron in 1897, and scientists at the Large Hadron Collider found the final piece of the puzzle, the Higgs boson, in 2012.

Use this interactive graphic to explore the different particles that make up the building blocks of our universe.

(Click here for the interactive graphic.)

via: Symmetry.org

bbc.com
Large Hadron Collider discovers new pentaquark particle - BBC News
Scientists at the Large Hadron Collider have announced the discovery of a new particle called the pentaquark.

Scientists at the Large Hadron Collider have announced the discovery of a new particle called the pentaquark.

It was first predicted to exist in the 1960s but, much like the Higgs boson particle before it, the pentaquark eluded science for decades until its detection at the LHC.

The discovery, which amounts to a new form of matter, was made by the Hadron Collider’s LHCb experiment.

The findings have been submitted to the journal Physical Review Letters.

There is no way that what we see could be due to something else other than the addition of a new particle –Dr Patrick Koppenburg, LHCb physics co-ordinator

In 1964, two physicists - Murray Gell Mann and George Zweig - independently proposed the existence of the subatomic particles known as quarks.

They theorised that key properties of the particles known as baryons and mesons were best explained if they were in turn made up of other constituent particles. Zweig coined the term “aces” for the three new hypothesised building blocks, but it was Gell-Mann’s name “quark” that stuck.

This model also allowed for other quark states, such as the pentaquark. This purely theoretical particle was composed of four quarks and an antiquark (the anti-matter equivalent of an ordinary quark).

Jargon

A while ago I posted on twitter that I was starting a collection of “lovely science jargon.” Quite a lot of wonderful people replied with their favorites, and I just realized I’d never done anything with that. So, here is a massively incomplete list of melifulous science jargon. (All of these, so far, are replies to this tweet. I tried to storify it so you could follow all the wonderful people, but Storify is being annoyingly bad.)

Helium Flash

Mohorovicic Discontinuity

Cosmological Constant

Golgi Apparatus

Ultraviolet Catastrophe

Superluminal

Shannon Entropy

Pipkrakes

A’a

Nonconformity

Normal Fault

Iron Catastrophe

Flowstone

Moonmilk

Punctuated Equilibrium

Islets of Langerhans

Genetic Drift

Chiral

Sinestral

Zones of Proximal Development

Legitimate Peripheral Participation

Phenomenological Primitives

Oxidative Phosphorylation

Smooth Endoplasmic Reticulum

Spaghettification 

Perverse Sheaf

Hopf Bifurcation

Nambu-Goldstone Boson

Circular Dichromism

Trivial

Dynamic Equilibrium

Allee Effect

Relative Verisimilitude

Yoichiro Nambu

Written by Sean Carroll

Recently (16 July 2015), Yoichiro Nambu passed away. He was aged 94, so it was after a very long and full life. 

Nambu was one of the greatest theoretical physicists of the 20th century, although not one with a high public profile. Among his contributions:

  • Being the first to really understand spontaneous symmetry breaking in quantum field theory, work for which he won a (very belated) Nobel Prize in 2008. We now understand the pion as a (pseudo-) “Nambu-Goldstone boson.”
  • Suggesting that quarks might come in three colors, and those colors might be charges for an SU(3) gauge symmetry, giving rise to force-carrying particles called gluons.
  • Proposing the first relativistic string theory, based on what is now called the Nambu-Goto action.

So — not too shabby.

But despite his outsized accomplishments, Nambu was quiet, proper, it’s even fair to say “shy.” He was one of those physicists who talked very little, and was often difficult to understand when he does talk, but if you put in the effort to follow him you would invariably be rewarded. One of his colleagues at the University of Chicago, Bruce Winstein, was charmed by the fact that Nambu was an experimentalist at heart; at home, apparently, he kept a little lab, where he would tinker with electronics to take a break from solving equations.

Any young person in science might want to read this profile of Nambu by his former student Madhusree Mukerjee. In it, Nambu tells of when he first came to the US from Japan, to be a postdoctoral researcher at the Institute for Advanced Study in Princeton. “Everyone seemed smarter than I,” Nambu recalls. “I could not accomplish what I wanted to and had a nervous breakdown.”

If Yoichiro Nambu can have a nervous breakdown because he didn’t feel smart enough, what hope is there for the rest of us?

Here are a few paragraphs I (Sean Carroll) wrote about Nambu and spontaneous symmetry breaking in The Particle at the End of the Universe.

A puzzle remained: how do we reconcile the idea that photons have mass inside a superconductor with the conviction that the underlying symmetry of electromagnetism forces the photon to be massless?

This problem was tackled by a number of people, including American physicist Philip Anderson, Soviet physicist Nikolai Bogoliubov, and Japanese-American physicist Yoichiro Nambu. The key turned out to be that the symmetry was indeed there, but that it was hidden by a field with that took on a nonzero value in the superconductor. According to the jargon that accompanies this phenomenon, we say the symmetry is “spontaneously broken”: the symmetry is there in the underlying equations, but the particular solution to those equations in which we are interested doesn’t look very symmetrical.

Yoichiro Nambu, despite the fact that he won the Nobel Prize in 2008 and has garnered numerous other honors over the years, remains relatively unknown outside physics. That’s a shame, as his contributions are comparable to those of better-known colleagues. Not only was he one of the first to understand spontaneous symmetry breaking in particle physics, but he was also the first to propose that quarks carry color, to suggest the existence of gluons, and to point out that certain particle properties could be explained by imagining that the particles were really tiny strings, thus launching string theory. Theoretical physicists admire Nambu’s accomplishments, but his inclination is to avoid the limelight.

For several years in the early 2000’s I was a faculty member at the University of Chicago, with an office across the hall from Nambu’s. We didn’t interact much, but when we did he was unfailingly gracious and polite. My major encounter with him was one time when he knocked on my door, hoping that I could help him with the email system on the theory group computers, which tended to take time off at unpredictable intervals. I wasn’t much help, but he took it philosophically. Peter Freund, another theorist at Chicago, describes Nambu as a “magician”: “He suddenly pulls a whole array of rabbits out of his hat and, before you know it, the rabbits reassemble in an entirely novel formation and by God, they balance the impossible on their fluffy cottontails.” His highly developed sense of etiquette, however, failed him when he was briefly appointed as department chair: reluctant to explicitly say “no” to any question, he would indicate disapproval by pausing before saying “yes.” This led to a certain amount of consternation among his colleagues, once they realized that their requests hadn’t actually been granted.

After the BCS theory of superconductivity was proposed, Nambu began to study the phenomenon from the perspective of a particle physicist. He put his finger on the key role played by spontaneous symmetry breaking, and began to wonder about its wider applicability. One of Nambu’s breakthroughs was to show (partly in collaboration with Italian physicist Giovanni Jona-Lasinio) how spontaneous symmetry breaking could happen even if you weren’t inside a superconductor. It could happen in empty space, in the presence of a field with a nonzero value — a clear precursor to the Higgs field. Interestingly, this theory also showed how a fermion field could start out massless, but gain mass through the process of symmetry breaking.

As brilliant as it was, Nambu’s suggestion of spontaneous symmetry breaking came with a price. While his models gave masses to fermions, they also predicted a new massless boson particle — exactly what particle physicists were trying to avoid, since they didn’t see any such particles created by the nuclear forces. Soon thereafter, Scottish physicist Jeffrey Goldstone argued that this wasn’t just an annoyance: this kind of symmetry breaking necessarily gave rise to massless particles, now called “Nambu-Goldstone bosons.” Pakistani physicist Abdus Salam and American physicist Steven Weinberg then collaborated with Goldstone in promoting this argument to what seemed like an air-tight proof, now called “Goldstone’s theorem.”

One question that must be addressed by any theory of broken symmetry is, what is the field that breaks the symmetry? In a superconductor the role is played by the Cooper pairs, composite states of electrons. In the Nambu/Jona-Lasinio model, a similar effect happens with composite nucleons. Starting with Goldstone’s 1961 paper, however, physicists become comfortable with the idea of simply positing a set of new fundamental boson fields whose job it was to break symmetries by taking on a nonzero value in empty space. The kind of fields required are known as a “scalar” fields, which is a way of saying they have no intrinsic spin. The gauge fields that carry forces, although they are also bosons, have spin equal to one.

If the symmetry weren’t broken, all the fields in Goldstone’s model would behave in exactly the same way, as massive scalar bosons, due to the requirements of the symmetry. When the symmetry is broken, the fields differentiate themselves. In the case of a global symmetry (a single transformation all throughout space), which is what Goldstone considered, one field remains massive, while the others become massless Nambu-Goldstone bosons — that’s Goldstone’s theorem.

good men are truly like. the higgs boson particle of the world, by which i mean you have to smash loads of normal ones together at great speeds to find the very rare Actually Good Man.