Scientific american 2015 pdf

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  3. Scientific American - May 2015 {Bindaredundat}.pdf
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December , WORLD. CHANGING. IDEAS. 10 big advances that will improve life, transform computing. Scientific American is the essential guide to the most awe-inspiring advances in science and technology, explaining how they change our understanding of the. Scientific American (ISSN ), Volume , Number 6, December , published monthly by Scientific American, a division of Nature.

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Scientific American 2015 Pdf

Scientific American investigates artificial enhancements, unpd/wpp/Publications/Files/Key_Findings_WPP_pdf. Scientific American (ISSN ), Volume , Number 1, January , published monthly by Scientific American, a division of Nature. December , Illustration by Alex Nabaum. WA. S. R. TELESCOPE. Old grudges between three teams of.

Jamie Spangler. As a Hopkins alumna, Dr. Spangler recently joined the Department of Biomedical Engineering and is interested in engineering antibody-based molecules that reshape immune cell behavior for targeted treatment of cancer, infectious diseases, and autoimmune disorders. Coffee and snacks will be provided! RSVP 's are appreciated. Inspirations of the Month Scientific American special issue: "It's not a women's issue" click here to download Our Story GWEN came about as we began to realize how poorly female graduate are connected and noticed the lack of support structure at the graduate level. After a few discussions, we came up with a plan: Connect, inspire, and empower women by building a network. The current mission of the Graduate Women Empowerment Network also known as GWEN is to increase the representation of women with graduate degrees at all levels of STEM professions, especially promoting those seeking leadership roles. GWEN has been growing steadily since its foundation in November, We aim to reach out to as many individuals as possible, men and women, who like us believe that we can make a difference by helping women scientists connect, inspire and empower each other. Make an Impact If you like what we do, please help us make an impact by spreading the word!

Imagine if the U. And yet in India, religious leaders became part of the solution. How sad that we have not made life better for our own sex workers because of belief systems infected with pride. The simulation would require a vast supply of hardware to run algorithms in parallel, or it would take an extremely long time. It also remarked below exerts more force on the wing that blocking the cutting of the prothan the faster air above, thereby lifting the plane.

Rather preventing the clipping of LexA might undermine the tack, not its shape. As for the topevolution of drug resistance in other side curvature of many wings, some microbes. Others pointed out that from rotavirus-caused diarrhea. It has a high signal-to-noise ratio. Ruiz, Jr. For a vetting of Shoreview, Minn. Without the lines, the both the Newtonian and Bernoullian explapuzzle has two solutions.

Collins, is it visit that same site for extra puzzles and sopossible to simulate a quantum comput- lutions to the grids in the article. In Ask the Experts, Stephen M. Glass indicated that two rota- in theory? The John J. For a more in-depth explabeen shown to be highly effective in Madison, Wis. This force also produces drag. The neutrino has been found. Frederick Reines and Clyde L. Cowan, Jr. The discovery of Neptune was a crowning achievement of classical physics: the motions of other planets showed it had to be there.

The neutrino is a similar achievement of modern physics, and its discovery is a vindication of the law of the conservation of energy. As regards the new aeroplane which Messrs. Thus may be explained the persistency with which mythology and folk lore allude to pygmy people.

At his own expense he sent out three expeditions. Two of them came to grief on the coast of South America, and the third was abandoned after cruising along the coast of Chile and Peru for several years in search of the treasure.

Within the case is a bell and spring hammer, the latter connected with a fob chain.

The supposition is, that the thief will pull the chain in order to obtain the prize. Forum by Van R. Europa is a compelling target. The proposed Europa funding stream punts the commitment to develop and launch a mission to a future president and Congress. It would also scout locations for a future mission to land. Browse and download any single issue from any year— to the present.

We discovered a lot in our long history. Now our award-winning Archives are available for download in digital format. Entries were matched with the Gini index. Infants are more likely to be born premature and underweight. Such disparities among teenagers. Children have higher rates of asthma. Disadvantaged adolescents reported less physical activity and more bodily aches and pains.

Day 7. Day 8. Return home with great memories! Visit Caravan. The earliest interventions may be most effective. Only in the past few years have researchers discovered that the uninjured side of the brain becomes more active after a stroke to help its fallen neighbor. Day 5. Enjoy two nights in picturesque Prince Edward Island. And we can all agree that adolescence is already tough enough.

Journey back in time as you visit the 18th century Fortress of Louisbourg. Leisurely afternoon in Charlottetown. New Brunswick and Prince Edward Island—Join the smart shoppers and experienced travelers who rely on Caravan for a wonderful vacation. In some instances. Day 9. Day 1. Guided stroll along historic Halifax waterfront.

Learn about the First Nation people of Nova Scotia. Enjoy two nights in Halifax. Day 3. Look for fin. Visit the idyllic artists' retreat of Peggy's Cove. Your adventure begins in Halifax. See rugged cliffs and breathtaking ocean views. Harvard Medical School now has a semester-long course in that vein. Day 4. Current stroke treatments largely target the damaged tissue.

It can even extend its own neurons across hemispheres to restore function. The gulf grew wider in countries with more economic inequality. Explore the Cabot Trail. Visit Nova Scotia. Ferry ride to Nova Scotia. Potential solutions to this escalating problem cover a wide swath. Visit the Anne of Green Gables house and stroll through settings from this literary classic.

Day One such drug. Visit the Maritime Museum. Day 2. Enjoy two nights in the charming town of Baddeck. One theory cannot be used to disprove another theory 2. Must include successful experiments and specific details 4. For more details. Once calibrated. The jet packs cost the National Laboratory of Atomic. Snowfall may have pulled the compounds out of the atmosphere. All facts must be verified by an encyclopedia 3. One example in nature must be submitted Theory: PMI accounted for a substantial part of this success.

Bush in There were million malaria cases globally in The program is based on four interventions: Efforts will even aim to eliminate the disease in some countries. The initiative is one of the largest players in the international effort to combat malaria. The program will also address drug and insecticide resistance to malaria.

Bernard Nahlen. Despite increases in the past decade. Kaiser Family Foundation. The program also helps target areas conduct regular insect screens above to identify problematic mosquito species below.

Answer these questions and more in Innovations in the Microbiome The human body plays host to a vast and diverse microbial community. From metabolic regulation to immunologic maintenance. Access this publication free online at scientificamerican.

Innovations in the Microbiome distils the most critical insights from the recent explosion in microbiome research. As science continues to unravel the host—microbiome relationship. In such a scenario. Under the old model. At a February demonstration in La Queue-en-Brie. The spring-autumn link most likely is bad news for humans.

The remote-controlled. Ecologists struggle to model the timing of current autumn seasons. The analysis. In the nation adopted civilian drone legislation that has begun to go into effect. Earlier this year personal flying bots were spotted hovering suspiciously over cultural and diplomatic landmarks in central Paris. Here in the U. This new thinking is hardly the final word on autumnal alterations. Leaves may be programmed to drop once they reach a certain age.

Or perhaps an early spring means trees siphon more groundwater from soil. Physicists are making major advancements with planar lenses that can scatter and bend rays of light. Such low-profile lenses would be useful for new kinds of compact. The latest rendition. As co-author Alexandre Ponomarenko.

The scientists are in talks with Google and other technology companies. The question is. Such lenses could reduce the bulk and cost of photography. But the lens worked on wavelengths of only one color—and not precisely at that.

And they could one day be printed on flexible plastic for thin.

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As we dream of smartphones that could roll up or slip into a wallet. A leap ahead came in Despite its lack of curvature. These delicious results could help clarify tough physics ideas for students. The researchers suspect instead that the pockets of heated water vapor within cause the noise as they burst through their starchy cages.

But with high-speed cameras in hand. Future cameras. The basic journey of hard kernel to fluffy morsel is straightforward. The team has since crafted a larger prototype. The millimeters-thick camera lens. Czaczkes Czaczkeswas wassurprised surprisedwhen whenhe he Tomer noticeddark darkpatches patchesaccumulating accumulatingininthe the noticed cornersofofthe thewhite whiteplaster plasternests nestsininwhich which corners hisblack blackgarden gardenants.

Another Anotherpossibility. Over Over his sevenyears yearsofofobservations. University UniversityofofRegensburg Regensburgbiologist biologist Thus. The Theick ick designed factorevolved evolvedfor forgood goodreason: Perhaps Perhapsititisisused usedfor fordefense. Honeybees Honeybees nests performso-called so-calleddefecation defecationflights.

Sure Sureenough. Czaczkes Czaczkeswill willhave havetoto them makenests nestswith withsee-through see-throughlids lidsand andwork work make underred redlight. Or Orititcould couldserve serveasasaasource sourceofofsalt salt material. Ants Antsiningeneral generalare arewell wellknown known handle fortheir theircleanliness—disposing cleanliness—disposingofofthe the for deadoutside outsidethe thenest nestand andleaving leavingfood foodscraps scraps dead and other waste in special refuse chambers.

Some Someants. To Tocovertly covertlywatch watch using themdo dotheir theirbusiness. Goldman Goldman Onward. For more information…and to join the panel. From time to time. Whether Whether all all those those bodies bodies will will actually actually prove prove to to be be habitable.

As a member of the panel. Your involvement with this exclusive community is always voluntary and the information you provide is strictly confidential. Astronomers Astronomers are are now now gearing gearing up up for for such such an an exploration.

Extra pieces allow two player competition. Losing Faith in Faith: From Preacher to Atheist. InInall allthe theintervening interveningtime.

Scientific American - May 2015 {Bindaredundat}.pdf

And Andcheek cheekby byjowl jowlwith withaatempestuous tempestuous M dwarf. Each code in the code book specifies a different set of pieces that assemble into a cube. Somewhat Somewhatcounterintuitively. There Thereisisaadownside. There are even two sections of simple puzzles for children. But Butatatsuch suchclose closeproximity. InInworst-case worst-casescescenarios. Adult May May Because Becauseofoftheir theirclosecloseininorbits.

They Theycan canspend spendhundreds hundredsofofmillions millions ofofyears yearsas asprotostars. Freethought Today. The codes are sorted by difficulty from easy to hard. A common flowering plant. American Heart Association. Give the women you care about the power to save their lives at GoRedForWomen.

Tannin is a compound that makes seed casings strong. In er. Penfield notes that the finding has attracted interest from scientists and agricultural companies alike. Also known as the Heart Fund. In cool weather. The investigators. Steven Ingebritsen. Geologists laden with temperature and pressure sensors. These stages. The same flow of magma below the surface powers both types of eruptions.

The most detailed data set yet on the explosive choreography between water and steam. But because of its popularity. Eventually these escaping bubbles make the water in the channel so hot that it boils and triggers a full eruption.

The measurements. Focusing too much on the latter meant researchers tended to overlook the breast trend. Something cues the brain to produce a substance called gonadotropin-releasing hormone. Family stress and chemical exposures in the environment may also play a role. The psychological effects. As a result.

Obesity appears to be the major factor sending girls into these unchartered waters. Other studies soon reached similar conclusions in Europe as well as the U. Breast development. This process activates the pituitary gland.

More and more families are finding themselves in the strange position of juggling stuffed animals and puberty talks with their first and second graders. Among the few exceptions are pituitary disorders. The most obvious physical consequence of early puberty is a prolonged exposure to estrogen. As for boys. Time has not resolved the puzzle.

From a biological point of view. Puberty was happening earlier in most girls and again differed by race: Fat cells manufacture the hormone as well. The ovaries are not the only place in the body where estrogen is produced.

That precocious development. Menstruation usually begins a few years later. The latest studies.

Scientific american september 2015 pdf

Pubic hair forms as the result of a different biological process. Clinicians say that slightly early development of breasts is likely not physically harmful and so does not require medical or pharmaceutical therapy for most girls. Those findings suggest the proportion of girls with significantly earlier breast development may still be ticking upward.

Ask the Experts: The Human Body and Mind?? Frank M. Biro cancer. Schools typically do not offer sexual education classes covering body maturation until fifth grade. Deardorff says. Identifying the triggers that push individual girls into early puberty remains a challenge that leaves parents short of a simple action plan. Puberty education should start earlier. Living in a homogeneous neighborhood may also be helpful: Helping daughters to maintain a healthy diet rich in fruits and vegetables may also offer some protection.

As Marcia E. What might that something else include? These substances. One way. Girls are not hapless creatures. Regardless of where girls live. The much smaller exposure to estrogen that occurs in conjunction with early breast development has not yet been definitively studied.

Children who are breast-fed appear to be less likely to enter puberty early. Deardorff and Greenspan believe. Parents and communities can also help protect girls from the painful psychological effects of early development. In a study published in Pediatrics.

Will every girl start maturing earlier? As researchers look for answers. It is unclear. Regular physical activity may prove beneficial to help counteract at least some of the trend toward early puberty by improving mood and combating weight gain. A study that tracked some 1. Other investigators have implicated intense stresses in childhood. Against that backdrop. May sensitive to conflict around her.

Discerning how much of an influence exposure to these chemicals might play is complicated. One thing mothers can do to try to avoid the problem in the first place is to breast-feed their children. The potential effect probably is minimal. He is also the father of three children. To really change the future of education for the better. TX March 9. We put education at the top of the agenda.

Scientific American and Macmillan education. That evening. A fellow panelist rolled his eyes. There are other ways to advertise to an on-the-go digital audience. GPS unit.

An ad that matches the typeface. You can send texts with permission. Social-media companies have signed on as well. But if advertisers truly believe in their material. Who downloads those anymore.

Scientific American - May 2015 {Bindaredundat}.pdf

With all the traditional channels shrinking. People are savvy. You can display a full-screen ad while a Web page or app is loading. And as the mobile era matures. But how. This trend. But what about journalistic independence? Game Boy. At a recent panel about the difficulty of advertising in the new.

An Interactive Advertising Bureau study found that only 41 percent of general-news readers could tell such ads apart from real news stories. In other words. Sometimes the labels disappear entirely. So who cares if people watch less regular TV. Banner ads on our devices are ugly and intrusive.

Even Web surfing on our regular computers is taking a hit. So far. But that could change. To overcome these various digital hurdles. On NYTimes. I heard an ad executive tell an impressive story. For now native ads will remain all the rage—with no laws governing them and no labeling standard. Truth in Digital Advertising As we consume more and more of our media on mobile devices. Media channels. She had gotten a musical performance—paid for by her soft drink client—seamlessly inserted into a TV awards show.

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Does Self-Esteem Matter? Learn about research on the self. Explore the state of astronomy in Australia. Topics include combinatorics the art of counting.

Exercise your curiosity. Jennifer Crocker. For more information email us at Info InsightCruises. Chart new science territory in Oceania with Scientific American Travel. Multiply your mental math abilities.

Adventure calls. Tap the energy and excitement of contemporary science aboard Bright Horizons Benjamin will demonstrate and explain how to perform amazing feats of mental calculation. Despite a huge volume of studies. Discrete Mathematics Learn the mathematics that underlie computer science and cryptography. My Favorite Numbers What makes the number 9 so magical?

Explore the beauty of the Fibonacci Numbers 1. How much should you bet? Learn the answer to these questions. For more info please email Info InsightCruises. The Program. The king of the dinosaurs. Brusatte is author of more than 70 technical articles and five books on dinosaurs. But they were unable to piece together when the tyrannosaurs origi- nated and what they evolved from because they lacked the fossils to do so.

He used his considerable platform to push pet ideas on eugenics and racial superiority. Yet its evolutionary history has eluded investigators. During the early 20th century Osborn was one of the most visible scientists in the U. But when the dirt and smoke cleared. Jurassic and Cretaceous periods.

These questions have remained unanswered until now. Construction did indeed stop that day because the bones turned out to be a major discovery. But they struggled to understand when the tyrannosaurs originated.

Climbing down to see what it was. These finds have made it possible to piece together the tyrannosaur family tree. These two finds painted a startling picture of the dawning of tyrannosaurs.

When this dinosaur was described a few years later. Big Bird from Hell. Osborn and Brown had unveiled the biggest. Although the fossils were impressive. These shared traits are signs of common ancestry: But this fame masked a puzzle: This geography explains why early tyrannosaurs have since turned up in Russia and China.

But this is a holy land for fossil hunters. I find it difficult to keep my eyes open during the three-and-a-halfhour train ride from Beijing through kilometer after kilometer of hilly countryside draped with haze and dotted with farms and billowing smokestacks. It turned out to be a vital clue to the rise of tyrannosaurs.

Osborn gave it a name whose brand value has stood the test of time: For instance. In his team announced a provocative discovery from the vast Krasnoyarsk region of central Siberia: Among the many beasts found in this Cretaceous Pompeii are two intriguing species of tyrannosaurs. At first glance. In addition. Even though I grew up in the boring plains of the American Midwest. Striking examples of this proliferation have come from Liaoning Province in northeastern China.

They lived at a time when the supercontinent Pangea had not yet fully broken apart. They revealed that the group did not begin as massive superpredators. The guy had good instincts. Alexander Averianov. My col- May But dinosaurs. Together the specimens also show that it took an amazingly long time for tyrannosaurs to rise to power: It was an oddball.

Repeated volcanic eruptions around million to million years ago quickly buried the ill-fated creatures in ash and mud. But tyrannosaur roots run far deeper than anyone expected. Over the past two decades farmers all around this region have collected thousands of dinosaur skeletons. If the tyrant king was not fearsome enough already. Over the next few decades. Brown himself was an eccentric character.

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Liaoning is not the most beautiful place in the world. Dilong The tiniest tyrannosaur. Yutyrannus Fossils of this large-bodied species from China were found covered with fluff. From Humble Beginnings. Eotyrannus Fossils of this long-fingered species come from the Isle of Wight off the southern coast of England. Russia and possibly Australia. Tyrannosaurus rex The tyrant king was one of the largest predators ever to walk the earth.

They may not have been top dogs, but they had found their niche as a steady, if unspectacular, group of stealthy, fleet-footed predators.

But then something changed. The allosaurs and ceratosaurs that had long occupied the apex of the food pyramid largely disappeared, and tyrannosaurs assumed the top predator role on the northern continents. However they got there, tyrannosaurs flourished once they reached the top of the food chain. They bit so hard that they crunched through the bones of their prey. They grew so fast that they put on a few kilograms of mass every day during their teenage years. Yet as successful as the colossal tyrannosaurs were in North America and Asia, they do not seem to have ever gained a foothold in Europe or the southern continents, where other groups of large predators prospered instead.

The world at that time was very different from the setting in which smaller tyrannosaurs first evolved. The conti-. Roughly the size of a golden retriever, it had long arms for catching prey and a lithe, leggy skeleton built for speed. The second species, which Xu described in , is a very different type of animal.

Both tyrannosaurs are found in the same rock formation and may have lived side by side approximately million years ago. Together these species, which exhibit the fused nasal bones and other hallmarks of tyrannosaurs, demonstrate that by the Early Cretaceous tyrannosaurs had branched off into a range of new species filling different ecological roles and that some were experimenting with larger body size.

Paleontologists once viewed dinosaurs as scaly, plodding, overgrown reptiles. In recent years, however, researchers have found evidence that a number of dinosaur species sported downy coats rather than scales and were generally more dynamic and smarter than they had previously been thought. Which is to say, they were more like birds than reptiles. The bones of these species are covered with a thick, feathery fluff—not the quill-pen feathers that make up the wings of living birds but simpler, filamentlike feathers that look like hair.

Unlike birds, tyrannosaurs certainly were not flying. Instead they probably used their feathers for display or to keep warm. If the tyrant king was not fearsome enough already, just imagine it as an energetic, intelligent, Big Bird from Hell. Furthermore, dramatically higher sea levels bisected North America and reduced Europe to a smattering of small islands. As a result, champions in one region might not be able to conquer another for one simple reason: The latest fossil discoveries suggest otherwise.

Here was a tyrannosaur from the latest part of the Cretaceous that was strikingly different from the tyrant lizard king. It was noticeably smaller—just about eight to nine meters long and probably around a ton in mass. The first of these creatures was known from part of a skeleton found in Mongolia by a Russian team in the s. Sometimes debates like this one rage for decades, as paleontologists await new fossils to break a stalemate. In our case, it took only a few years, along with the dumb luck of the backhoe operator.

It was the clincher: Fiorillo and Tykoski came up with an idea that may sound farfetched but one I think is very plausible: Many modern island-dwelling animals have undergone dwarfing for that same reason. Where did tyrannosaurs originate, and did they get their start even earlier than the Middle Jurassic, perhaps during the Early Jurassic, a time when we have few fossils from around the world?

Most of their fossils are from the northern continents, except for one enigmatic bone from Australia. Incomplete as the tyrannosaur story is, it still reveals a deeper truth about evolution—namely that is not predictable. When tyrannosaurs originated more than million years ago, no one would have guessed that these puny stalkers would come to rule entire continents. They were not preordained for success.

And then one day, when the tyrannosaurs were at the peak of their game, an asteroid fell from the sky and they disappeared. Their strength and size could not save them as wildfires raged, ecosystems collapsed and mammals began their march to the top. Tyrannosaur Paleobiology: New Research on Ancient Exemplar Organisms. Stephen L. Brusatte et al. Fiorillo and Ronald S. Gregory M. Erickson; September Physicists have known for decades that particles called gluons keep protons and neutrons intact— and thereby hold the universe together.

Accelerator experiments in the past half a century have created a host of other particles containing quarks and antiquarks. With a little luck. Then scientists in the 20th century split the atom.

The Higgs mechanism is often said to account for the origin of mass in the visible universe. These particles each consist of three quarks and varying numbers of gluons. Ongoing and future work. This statement. We have a pretty good grasp of how quarks and leptons—a category of particles that includes electrons—get their mass. For example. If physicists could answer these questions. And protons and neutrons are not the only particles made of quarks found in the universe.

Despite all this insight—and a good understanding of how individual quarks and gluons interact with one another—physicists. Physicists have made huge strides in understanding the workings of quarks and gluons. Experimental methods for peering inside protons and neutrons reveal a full-fledged symphonic orchestra within. When particles pass through this field.

Identifying the main enigmas surrounding quarks and gluons. Protons and neutrons. His recent efforts focus on the realization of an electron-ion collider. These particles. He is associate director of experimental nuclear physics there and has been a spokesperson for multiple experiments studying the quark-gluon structure of hadrons and atomic nuclei. Higgs The strong force is one of the four fundamental forces of nature. Gluons transmit the most powerful of all the forces—the strong force.

But the strong force sometimes acts in sur. But how gluons help to generate proton and neutron mass is not evident. Because the energy of a proton is mostly contributed by gluons. In contrast to electromagnetism.

Of these four. The other 98 percent. Calculating the energy of gluons is difficult. According to quantum mechanics. In addition to binding quarks together to form hadrons. The electromagnetic force. This So far so good. Electron Muon Tau But this force is itself puzzling. Quarks come in six types. Yet quarks and gluons almost never exist in isolation. Just as the photon—the fundamen. Besides bosons. This cacophony complicates a number of fundamental questions.

In addition to the main three quarks. Atomic Structure: Two Views The classic picture of an atom shown below has electrons orbiting a nucleus of protons and neutrons made of three quarks each. But the image at the right shows the quantum foam—a truer. One way physicists attempt to resolve these mysteries is by considering the theoretical properties of.

In addition to the basic quark trio. Exotic States of Matter Physicists have theorized and. Glueballs and Their Kin Theoretical simulations suggest that quarks and gluons can combine to create other particles beyond protons and neutrons. Strong hints of such a state have appeared in particle accelerators. By studying the plasma as it cools. Accelerators on Earth recently succeeded in replicating this state. The new gluons. These exotic states offer new possibilities for studying the interactions that can occur between quarks and gluons—potentially helping to resolve some basic mysteries of matter.

Quarks and gluons buzzed around freely in a roiling swarm. There is now increasing evidence that tetra quarks have been found. This impediment persists because the equations of QCD are fiendishly difficult to solve at the large distances where the interaction strength between quarks and gluons becomes very strong.

In the decades since the advent of QCD. In contrast. Their rebound speed and direction revealed the presence and arrangement of the quarks inside protons. When they are close to each other. The concept of color does help clarify why the strong force behaves so differently from the electromagnetic force.

But despite some progress. Theory suggests it could go on forever—yet we know it does not. Strong self-interactions cause them to repel one another. The daughter gluons. If gluons continued to procreate. Frank Wilczek and H. Sometimes the electrons passed right through. When the growth in gluon number tapers. This implication of quantum chromodynamics is a big leap from electromagnetism—photons do not interact with one another. Because matter is obviously stable we exist. Physicists think.

Just how string breaking occurs is another mystery we cannot fully explain. Yet many details of QCD remain elusive. Physicists first observed quarks in the s. One idea is that nature manages to put up a maximum occupancy sign when gluons become so numerous that they begin to overlap within the proton. All colored particles interact by exchanging gluons.

This force between quarks corresponds to a weight of 16 metric tons at separations that are roughly the size of a proton. The quarkantiquark fluctuation makes the interaction strength between color charges stronger. This conjectured saturated gluon state.

This splitting of gluons resembles an out-of-control popcorn machine. Physicists David J. Physicists think that when protons and neutrons reach extreme speeds. When they move farther apart. The strong force is also peculiar in that it seems to pull on quarks more strongly the farther away they get.

The string snaps. A gluon can temporarily become either a quark-antiquark pair or a gluon pair before turning back into a single gluon. David Politzer won the Nobel Prize in Physics for this discovery. QCD should also explain how protons and neutrons overcome the powerful electromagnetic repulsion between protons to stick together inside atoms. Color neutrality of hadrons is analogous to the electrical charge neutrality of atoms. These so-called deeply inelastic scattering DIS experiments showed that quarks attract one another weakly at short distances.

Because such gluon oscillations are more prevalent than the quark exchanges in QCD. And we lack a mathematical proof of how the QCD equations ensure that colored quarks and gluons are confined within colorless hadrons. In addition to the basic three quarks. To visualize how the strong force works. The electron-ion collider EIC project would achieve unparalleled levels of intensity. Is the force field limiting the amount of gluons that can build up inside the color glass condensate the same as the confining field that holds protons together in the first place?

If so. This plasma is the hottest matter ever created on Earth. All hadrons have spin.. Over the past four decades since the formulation of quantum chromodynamics. It forms when atomic nuclei collide at close to light speed. In contrast to previous experiments that smashed fast-moving electrons at stationary nuclear targets.

Hadrons with differing spins precess and curl in different directions in the fields of powerful magnets.

The increase in crashes. This situation may be about to change significantly. In level of detail. Simulations suggest that additional colorless hadrons may exist. Physicists have recently discovered another extreme state of matter known as a quark-gluon plasma.

The quark-gluon plasma bears a strong similarity to the early universe. And by engineering the destruction of protons and neutrons into plasma in this way. By probing this state using more powerful DIS experiments than are currently available.


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