Fortunetelling Verdict Raises Thorny Questions

Last week a federal judge in Alexandria, Louisiana, overturned a law banning fortunetelling on the basis that it is free speech protected by the First Amendment.

U.S. District Judge Dee Drell struck down an ordinance outlawing fortunetelling, astrology, palm reading, tarot, and other forms of divination on the grounds that the practices are fraudulent and inherently deceptive. The case involved a fortuneteller named Rachel Adams who sued to overturn the law and won.

About one in seven Americans have consulted a psychic or fortuneteller, and their services are in high demand, especially during hard economic times. This curious case raises issues about the boundary between freedom of speech and fraudulent (or at least unproven) claims.

There are, of course, exceptions to free speech that go beyond yelling fire in a crowded theater. People who lie on their tax returns can be convicted of tax evasion, and those who lie in a court of law can be convicted of perjury, which under federal law is a felony. Companies, also, are legally prohibited from making false statements about their merchandise; Ford cannot claim its cars get 200 miles per gallon, and vitamin manufacturers cannot advertise that their pills cure cancer. But other cases are murkier.

Free Speech and The Right to Lie

Last month the Supreme Court ruled that Xavier Alvarez, a public official who falsely claimed that he had received the Medal of Honor, could not be prosecuted under the Stolen Valor Act, a 2006 law that made it a crime to falsely claim “to have been awarded any decoration or medal authorized by Congress for the Armed Forces of the United States.” Alvarez admitted that his statements were false, but claimed that his lies were free speech protected by the First Amendment. The Supreme Court agreed and overturned the law.

The First Amendment freedom to lie and misrepresent matters of fact was even invoked by top Wall Street credit rating companies including Standard & Poor’s, Moody’s Investors Service, and others. In the months and years leading up to the global financial crash, these companies routinely inflated the ratings of billions of dollars worth of investments they bought and sold. When investors and investigators demanded to know why companies that were given stellar confidence ratings one day went bankrupt the next, the agencies claimed that their investment ratings were merely “opinions” not necessarily based on truth or fact, and as such were protected by the First Amendment.

Psychics and fortunetellers try a similar strategy, often offering their services “for entertainment only,” a tacit acknowledgement that the information they provide may not be reliable. Yet the fact is that—like clients of credit rating companies—the clients of psychics often do take the advice they get seriously, making life, love, and career decisions based upon fortunetelling. If clients truly are seeking only entertainment, for the $40 to $100 per hour psychics typically charge there are far cheaper ways to be entertained.

Some fortunetellers offer readings for fun and pleasure, and for the most part it’s not palm reading per se that police are concerned about, it’s the confidence schemes, theft by deception, and fraud that often accompany fortunetelling. One common scam involves luring clients in with inexpensive readings, then convincing them that a recent misfortune is the result of a curse put on them by an enemy. The imaginary curse can be lifted but it won’t come cheap, and some victims have been robbed of tens of thousands of dollars. In one recent case a “psychic” misused the influence and trust placed in him to sexually exploit several women.

Read more at Discovery News

Dolphins May Be Math Geniuses

Dolphins may use complex nonlinear mathematics when hunting, according to a new study that suggests these brainy marine mammals could be far more skilled at math than was ever thought possible before.

Inspiration for the new study, published in the latest Proceedings of the Royal Society A, came after lead author Tim Leighton watched an episode of the Discovery Channel's "Blue Planet" series and saw dolphins blowing multiple tiny bubbles around prey as they hunted.

"I immediately got hooked, because I knew that no man-made sonar would be able to operate in such bubble water," explained Leighton, a professor of ultrasonics and underwater acoustics at the University of Southampton, where he is also an associate dean.

"These dolphins were either 'blinding' their most spectacular sensory apparatus when hunting -- which would be odd, though they still have sight to reply on -- or they have a sonar that can do what human sonar cannot…Perhaps they have something amazing," he added.

Leighton and colleagues Paul White and student Gim Hwa Chua set out to determine what the amazing ability might be. They started by modeling the types of echolocation pulses that dolphins emit. The researchers processed them using nonlinear mathematics instead of the standard way of processing sonar returns. The technique worked, and could explain how dolphins achieve hunting success with bubbles.

The math involved is complex. Essentially it relies upon sending out pulses that vary in amplitude. The first may have a value of 1 while the second is 1/3 that amplitude.

"So, provided the dolphin remembers what the ratios of the two pulses were, and can multiply the second echo by that and add the echoes together, it can make the fish 'visible' to its sonar," Leighton told Discovery News. "This is detection enhancement."

But that's not all. There must be a second stage to the hunt.

"Bubbles cause false alarms because they scatter strongly and a dolphin cannot afford to waste its energy chasing false alarms while the real fish escape," Leighton explained.

The second stage then involves subtracting the echoes from one another, ensuring the echo of the second pulse is first multiplied by three. The process, in short, therefore first entails making the fish visible to sonar by addition. The fish is then made invisible by subtraction to confirm it is a true target.

In order to confirm that dolphins use such nonlinear mathematical processing, some questions must still be answered. For example, for this technique to work, dolphins would have to use a frequency when they enter bubbly water that is sufficiently low, permitting them to hear frequencies that are twice as high in pitch.

"Until measurements are taken of wild dolphin sonar as they hunt in bubbly water, these questions will remain unanswered," Leighton said. "What we have shown is that it is not impossible to distinguish targets in bubbly water using the same sort of pulses that dolphins use."

If replicated, the sonar model may prove to be a huge benefit to humans. It might be able to detect covert circuitry, such as bugging devices hidden in walls, stones or foliage. It could also dramatically improve detection of sea mines.

"Currently, the navy uses dolphins or divers feeling with their hands in such difficult conditions as near shore bubbly water, for example in the Gulf," he said.

Read more at Discovery News

Exoplanet Neighbor is Smaller than Earth

Astronomers believe they have found a planet about two-thirds the size of Earth orbiting a star 33 light-years away, a virtual neighbor in cosmic terms.

Don't pack your suitcase yet. The planet, known as UCF-1.01, is not very hospitable, with temperatures that exceed 1,000 degrees Fahrenheit, a surface that may be volcanic or molten and little if any atmosphere.

It's not just a summer heat wave. For UCF-1.01, it's a way of life. The planet is located so close to its parent star, a red dwarf known as GJ 436, that it completes an orbit in 1.4 Earth days.

Astronomers were following up studies of a Neptune-sized world already known to be orbiting GJ 436 when they realized there may be one -- or even two -- additional planets in the system.

Confirmation, however, will require telescopes more sensitive than what is currently available.

The studies were conducted with NASA's Spitzer infrared space telescope, which recorded slight, regular dips in the amount of light coming from the star. This phenomenon could be due to a planet passing in front of its parent star, relative to the telescope's view.

NASA's Kepler space telescope uses this technique to look for so-called transiting planets. The smaller the planet, however, the more difficult the search.

Of Kepler's 1,800 candidate planet-hosting stars, only three have been confirmed to have worlds smaller than Earth and just one is believed to be smaller than Spitzer’s potential find.

Read more at Discovery News

Weird Ancient Spiral Galaxy Discovered

Astronomers have discovered a three-armed spiral galaxy dating back nearly 11 billion years -- much older than similarly structured objects that are common in the modern universe.

The discovery was so jarring, scientists at first didn't believe their data.

"Our first thought was that we must have the wrong distance for the galaxy," lead researcher David Law, with the University of Toronto, told Discovery News.

"Then we thought perhaps it was the human brain playing tricks on us. If you look at enough blobby, weird-looking galaxies sooner or later, like a Rorschach blob test, you start to pick out patterns whether or not they're there," Law said.

Follow-up observation, however, showed that the galaxy, known as Q2343-BX442 and located in the direction of the Pegasus constellation, was not a mass of clumpy galaxies, but indeed a regular, rotating, spiral disk galaxy, albeit a thicker and puffier rendition of modern day spiral galaxies, such as the Milky Way.

The Hubble Space Telescope was used to image the galaxy's spiral structure, but to prove the spirals were indeed rotating, the researchers used the Keck II telescope in Hawaii to study the object's internal motions.

"It was shocking," said astronomer Alice Shapley, with the University of California, Los Angeles. "At redshift 2, where we found this galaxy, there hadn't been any other spirals or any other rotating disk galaxies found. We don't know of any other samples like this."

Most galaxies dating back to redshift 2, a cosmic yardstick that equates to about 10.7 billion years old, look lumpy and irregular, without symmetry.

"They're kind of like train wrecks," Shapley told Discovery News.

Out of sample of 306 Hubble Space Telescope images of ancient galaxies, just one -- BX442 -- had this beautiful spiral pattern, she added.

Scientists believe the galaxy's shape is due to gravitational effects of a small intruder galaxy. If that is true, BX442's days as a spiral are numbered.

Computer simulations show BX442, a relatively large galaxy with about the same mass as the Milky Way, would last about 100 million years as a spiral structure, a relative blink in cosmic time.

"We think that we just happened to catch it at a very special time," Shapley said. "I'd say by today, it probably doesn't look like a spiral galaxy."

Other spiral galaxies, like our own Milky Way, are longer-lived.

"One of the leading mechanisms that we believe explains modern day spirals, such as the Milky Way, is what is called 'density wave theory,' which doesn't need any kind of nearby galaxy. It happens from the disk alone in isolation," Law said.

Read more at Discovery News

Cannabis 'Pharma Factory' Discovered

U of S researchers have discovered the chemical pathway that Cannabis sativa uses to create bioactive compounds called cannabinoids, paving the way for the development of marijuana varieties to produce pharmaceuticals or cannabinoid-free industrial hemp. The research appears online in the July 16 early edition of the Proceedings of the National Academy of Sciences (PNAS).

U of S adjunct professor of biology Jon Page explains that the pathway is an unusual one, involving a specialized version of one enzyme, called hexanoyl-CoA synthetase, and another enzyme, called olivetolic acid cyclase (OAC), that has never before been seen in plants.

"What cannabis has done is take a rare fatty acid with a simple, six-carbon chain and use it as a building block to make something chemically complex and pharmacologically active," Page says.

Page led the research with PhD student Steve Gagne, who discovered OAC, and postdoctoral researcher Jake Stout, who discovered hexanoyl-CoA synthetase (reported earlier this year in The Plant Journal).

Cannabis has been cultivated for thousands of years for food, fibre, medicine and as a psychoactive drug. Cannabinoids such as delta-9-tetrahydrocannabinol, or THC, are produced on the flowers of the female plant in tiny hair-like structures called trichomes, the plant's own "chemical factories." The researchers used genomic analysis of isolated trichome cells to produce a catalog of the genes involved in cannabinoid production.

Page and his colleagues have already used the new enzymes to coax yeast to produce olivetolic acid, a key metabolic intermediate on the biochemical pathway that leads to cannabinoids.

"Now that we know the pathway, we could develop ways to produce cannabinoids with yeast or other microorganisms, which could be a valuable alternative to chemical synthesis for producing cannabinoids for the pharmaceutical industry," Page says.

There are more than 100 known cannabinoids, only a few of which have been explored for their possible medicinal uses. THC is the main psychoactive cannabinoid, responsible for the "high" sought by recreational users, as well as medicinal effects such as pain relief, nausea suppression and appetite stimulation. More than 19,000 patients in Canada are authorized to legally use marijuana to benefit from these effects, and many others use cannabinoid-containing drugs via prescription. Another important cannabinoid, cannabidiol (CBD) has anti-anxiety and neuro-protective properties.

Page explains that knowledge of the cannabinoid-making pathway could also make matters easier for Canadian farmers. Plant breeders can now look for cannabis strains that lack key parts of the cannabinoid-making pathway, which would allow for zero-THC varieties (current Canadian regulations call for no more than 0.3 per cent THC for industrial hemp, compared to 15 per cent or higher in the more potent marijuana varieties).

Although hemp cultivation in Canada dates back to the 1600s in Quebec, today industrial hemp is a niche crop, grown mostly on the Prairies. Its popularity fluctuates considerably, with about 15,700 hectares (39,000 acres) grown in 2011 according to statistics from Health Canada, which regulates the crop.

While hemp is well-known as a fibre crop for everything from textiles, rope and paper, it is more often grown in Canada for its seed. Hemp seed, which is high in omega-3 and omega-6 fatty acids, is marketed for its healthy qualities. It is used in everything from lactose-free hemp milk, breakfast cereals, snack foods and protein supplements for athletes. Hemp oil is also used in cosmetic skin care products.

Read more at Science Daily

Defining the Mechanical Mechanisms in Living Cells

If you place certain types of living cells on a microscope slide, the cells will inch across the glass, find their neighbors, and assemble themselves into a simple, if primitive tissue. A new study at Stanford University may help explain this phenomenon, and then some, about the mechanical structure and behavior of complex living organisms.

In the paper published in the Proceedings of the National Academy of Sciences, chemical engineer Alexander Dunn, PhD, and a multidisciplinary team of researchers in biology, physiology, and chemical and mechanical engineering, were able to measure -- and to literally see -- the mechanical forces at play between and within the living cells.

There are scads of data explaining chemical signaling between cells. "And yet, one of the great roadblocks to a complete knowledge of how cells work together to form tissues, organs and, ultimately, us, is an understanding of the mechanical forces at play between and within cells," said Dunn.

Using a new force-sensing technique, Dunn and team have been able to see mechanical forces at work inside living cells to understand how cells connect to one another and how individual cells control their own shape and movement within larger tissues.

Pulling back the veil on the exact nature of this mechanism could have bearing on biological understanding ranging from how tissues and tumors form and grow, to the creation of entire complex living organisms.

Seeing the force

"Cells are really just machines. Small, incredibly complex biological machines, but machines nonetheless," said Dunn. "They rely on thousands of moving parts that give the cell shape and control of its destiny."

The mechanical parts are proteins whose exact functions often remain a mystery, but Dunn and team have helped explain the behaviors of a few.

At its most basic level, a cell is like a balloon filled with saltwater, Dunn explained. The exterior of the cell, the balloon part, is known as the membrane. Protruding through the membrane, with portions both inside and outside the cell, are certain proteins called cadherins.

Outside of the cell, cadherins bind one cell to its neighbors like Velcro. The 'herin' portion of the name, in fact, shares a Latin root with "adhere."

On the inside of the cell, cadherin is connected to long fibers of actin and myosin that stretch from membrane to nucleus to membrane again. Actin and myosin work together as the muscle of the cell, providing tension that gives the cell shape and the ability to control its own movement. Without this force, the balloon of the cell would be a shapeless, immobile blob.

Puppeteer's string
"If you watch a cell moving across a glass slide, you can see it attach itself on one side of the cell and detach on the other, which causes a contraction that allows the cell to, bit by bit, pull itself from place to place," said Dunn. "It's clearly moving itself."

While it was understood that cadherin and actin are connected to one another by other proteins known as catenins, what was not known was how, when, and where the cells might be using their muscles (actin and myosin) to tug on the Velcro (cadherin) that holds them to other cells.

This is an important problem in the development of organisms, since a cell must somehow control its shape and its attachments to other cells as it grows, divides, and migrates from one place to another within the tissue. Dunn and his colleagues have shown that the actin-catenin-cadherin structure transmits force within the cell and, further, that cadherin can convey mechanical forces from one cell to the next.

It is a form of mechanical communication, like the strings of a puppeteer. Dunn and others in the field believe that these mechanical forces may be important in conveying to a cell how to position itself within a tissue, when to reproduce and when to stop as the tissue reaches its proper size and shape.

"That is the theory, but an important piece was missing," said Dunn. "Our research shows that forces at cell-cell contacts can in fact be communicated from one cell to its neighbors. The theorized mechanical signaling mechanism is feasible."

Story within a story

How Dunn and his colleagues got to this point is a story in itself. It reads like the recipe for a witch's potion -- cultured canine kidney cells, DNA from jellyfish and spider silk, and microscopic glass needles.

To measure the force between cells, a team combining the skill of several Stanford laboratories -- headed by Professor Dunn in chemical engineering, professors William Weis and W. James Nelson in the Department of Molecular and Cellular Physiology and associate professor of mechanical engineering Beth Pruitt -- used a tiny and ingenious molecular force sensor developed by Martin Schwartz and colleagues at the University of Virginia. The sensor combines fluorescent proteins from jellyfish with a springy protein from spider silk.

The genes for the sensor are incorporated into the cell's DNA. Under illumination, the cells glow in varying colors depending on how much stretch the sensor is under. In this study, the force sensor is inserted into the cadherin molecules -- when the Velcro stretches, so does the sensor.

The team then took things a step further. By turning the activity of myosin, actin and catenin on and off, they were able to determine that these proteins are in fact linked together and are at the heart of inter- and intra-cellular mechanical force transmission.

Lastly, using glass microneedles, the team tugged at connected pairs of cells, pulling at one cell to show that force gets communicated to the other through the cadherin interface.

"At this point we now know that a cell exerts exquisite control over the balance of its internal forces and can detect force exerted from outside by its neighbors, but we still know next to nothing about how," said Dunn. "We are extremely curious to find out more."

Read more at Science Daily

Engineering Technology Reveals Eating Habits of Giant Dinosaurs

High-tech technology, traditionally usually used to design racing cars and aeroplanes, has helped researchers to understand how plant-eating dinosaurs fed 150 million years ago.

A team of international researchers, led by the University of Bristol and the Natural History Museum, used CT scans and biomechanical modelling to show that Diplodocus -- one of the largest dinosaurs ever discovered -- had a skull adapted to strip leaves from tree branches.

The research is published today (July 16, 2012) in the natural sciences journal Naturwissenschaften.

The Diplodocus is a sauropod from the Jurassic Period and one of the longest animals to have lived on Earth, measuring over 30 metres in length and weighing around 15 tonnes.

While known to be massive herbivores, there has been great debate about exactly how they ate such large quantities of plants. The aberrant Diplodocus, with its long snout and protruding peg-like teeth restricted to the very front of its mouth, has been the centre of such controversy.

To solve the mystery, a 3D model of a complete Diplodocus skull was created using data from a CT scan. This model was then biomechanically analysed to test three feeding behaviours using finite element analysis (FEA).

FEA is widely used, from designing aeroplanes to orthopaedic implants. It revealed the various stresses and strains acting on the Diplodocus' skull during feeding to determine whether the skull or teeth would break under certain conditions.

The team that made this discovery was led by Dr Emily Rayfield of Bristol University's School of Earth Sciences and Dr Paul Barrett of The Natural History Museum in London. Dr Mark Young, a former student working at both institutions, ran the analyses during his PhD.

Dr Young said: "Sauropod dinosaurs, like Diplodocus, were so weird and different from living animals that there is no animal we can compare them with. This makes understanding their feeding ecology very difficult. That's why biomechanically modelling is so important to our understanding of long-extinct animals."

Dr Paul Barrett added: "Using these techniques, borrowed from the worlds of engineering and medicine, we can start to examine the feeding behaviour of this long-extinct animal in levels of detail which were simply impossible until recently."

Numerous hypotheses of feeding behaviour have been suggested for Diplodocus since its discovery over 130 years ago. These ranged from standard biting, combing leaves through peg-like teeth, ripping bark from trees similar to behaviour in some living deer, and even plucking shellfish from rocks.

Read more at Science Daily

When Galaxies Collide: Beautiful Images of Cosmic Impacts

Galactic collisions are among the most ferocious and stunning events in our universe.

These cosmic pile-ups occur whenever galaxies become gravitationally attracted to one another. Multiple galaxies may spiral around each other for billions of years, creating odd distortions and beautiful trails of stars as they pass. Eventually, the objects crash together in a forceful embrace.

Since the first galaxies coalesced several hundred million years after the Big Bang, their collisions have been influential in shaping the history of our universe.

“As small galaxies merge, they make larger galaxies, and those will then merge to make still larger galaxies, and so on, up to and including the present-day galaxies,” said astronomer Kirk Borne of George Mason University.

Because of the vast distances between them, there's a low probability that stars within galaxies will actually hit head-on. But gravitational forces can wrest stars from their previous orbits, scrambling the shape of the galaxies involved.

Friction between diffuse gas and dust inside each galaxy raises temperatures, and interstellar material often combines into huge molecular clouds. All this mass in one place triggers prodigious star formation, with stellar birth rates increasing by a hundredfold.

The increased light from this extra star formation allows astronomers to see galaxy mergers in the distant universe, helping them learn about some of the earliest periods of cosmic history. Understanding how larger galaxies coalesce from smaller galaxies provides important information on our own cosmic origin story: the formation of the Milky Way galaxy.

The Milky Way formed through the long-ago merging of progenitor galaxies and is on course to hit our neighbor, the Andromeda galaxy, in about 4 billion years. Simulations indicate that the Earth and solar system won’t be destroyed in this collision, though the sun may be tossed into a brand new galactic region.

Along with other astronomers, Borne is a member of the Galaxy Zoo project, an online collaboration between scientists and interested citizens to sift through astronomical telescope datasets and classify galaxies and their behavior. His specialty is the Galaxy Zoo: Mergers project, which studies galactic collisions.

Their website has an online Java applet that lets anyone simulate galaxies smashing together. Just input parameters like the galaxies’ relative masses, collision speeds and angles, and then watch the results.

The applet's purpose is to find the initial conditions for different real-world galaxy collisions. Volunteers on the project have run more than 3 million simulations and found models describing 54 real-world galaxies, said astronomer John Wallin, the Galaxy Zoo: Mergers project lead.

The project's initial data was recently presented at a cosmology workshop in Santa Fe, New Mexico, and they're still looking for more help. Volunteers can participate in Merger Wars, where different simulated outcomes are pitted against one another to see which best describes actual galaxy collisions.

On the following pages, Wired takes a look at some of the most amazing images ever taken of these cosmic pile-ups.

Above:
Antennae Galaxies

One of the most spectacular galactic mergers is known as the Antennae galaxies. Located about 62 million light-years away in the constellation Corvus, the object contains a jewelry case of stars that shine in the visible, infrared, and X-ray wavelengths in this image. The colliding galaxies have nearly engulfed one another since they first began to unite around 100 million years ago, triggering an intense period of star formation.

Read more and see more pictures at Wired Science

In Case of Alligator Attack...

Even though alligators have been around for nearly 40 million years, they're still making headlines. In the past week, two Florida teenagers have been victims of alligator attacks, but were able to fend the gators off.

At Keaton Beach near Tallahassee, 15-year-old Kaleb Towles was spearfishing with his grandfather when a 10-foot-long alligator bit him across the chest. The alligator released its grip, and later Towles and his grandfather managed to kill it.

Earlier in the week, 17-year-old Kaleb "Fred" Langdale was swimming near Moore Haven, Fla., when he lost the lower half of his right arm trying to fend off an attack from an 11-foot-long alligator. The teen's quick thinking saved his life.

During the warmer weather months, alligators becomes more active as their metabolism increases. This time happens to be when alligators mate, making them more aggressive than they would be otherwise. As a result, alligator attacks can increase in frequency during the summer months.

Given how large the alligators were in both cases, both teenagers are fortunate to have survived their attacks. As Julienne Gage reported for Discovery News, between 2000 and 2010, nearly 13 people died as a result of attacks from alligators. Although alligator attacks are less frequent than shark attacks, they're more often fatal. And because of suburban sprawl, encounters between alligators and humans have increased slightly.

So while an alligator attack might be rare, knowing what to do should that unlikely event occur could be life-saving. Growing up in Florida, I remember being told that in the event of an encounter with an aggressive alligator on dry land, the best way to get away from it would be to run along a zig-zag, the thinking being that alligators would attempt to follow but be unable to since their bodies couldn't allow them to manuever quick turns. But is that really true? And what's the best way to survive an attack that takes place in water?

For starters, if you encounter an alligator on dry land, just run. Zig-zagging would only slow you down, so running in a straight line is the way to go. As Amy Hunter writing for HowStuffWorks.com points out, an alligator's running speed on land tops out at 11 miles per hour. They also can't run for very long, which makes it unlikely they'll put up much of a chase.

Read more at Discovery News

Instrument for Exploring the Cosmos and the Quantum World Created

Researchers at the California Institute of Technology (Caltech) and NASA's Jet Propulsion Laboratory (JPL) have developed a new type of amplifier for boosting electrical signals. The device can be used for everything from studying stars, galaxies, and black holes to exploring the quantum world and developing quantum computers.

"This amplifier will redefine what it is possible to measure," says Jonas Zmuidzinas, Caltech's Merle Kingsley Professor of Physics, the chief technologist at JPL, and a member of the research team.

An amplifier is a device that increases the strength of a weak signal. "Amplifiers play a basic role in a wide range of scientific measurements and in electronics in general," says Peter Day, a visiting associate in physics at Caltech and a principal scientist at JPL. "For many tasks, current amplifiers are good enough. But for the most demanding applications, the shortcomings of the available technologies limit us."

Conventional transistor amplifiers -- like the ones that power your car speakers -- work for a large span of frequencies. They can also boost signals ranging from the faint to the strong, and this so-called dynamic range enables your speakers to play both the quiet and loud parts of a song. But when an extremely sensitive amplifier is needed -- for example, to boost the faint, high-frequency radio waves from distant galaxies -- transistor amplifiers tend to introduce too much noise, resulting in a signal that is more powerful but less clear.

One type of highly sensitive amplifier is a parametric amplifier, which boosts a weak input signal by using a strong signal called the pump signal. As both signals travel through the instrument, the pump signal injects energy into the weak signal, therefore amplifying it.

About 50 years ago, Amnon Yariv, Caltech's Martin and Eileen Summerfield Professor of Applied Physics and Electrical Engineering, showed that this type of amplifier produces as little noise as possible: the only noise it must produce is the unavoidable noise caused by the jiggling of atoms and waves according to the laws of quantum mechanics. The problem with many parametric amplifiers and sensitive devices like it, however, is that they can only amplify a narrow frequency range and often have a poor dynamic range.

But the Caltech and JPL researchers say their new amplifier, which is a type of parametric amplifier, combines only the best features of other amplifiers. It operates over a frequency range more than ten times wider than other comparably sensitive amplifiers, can amplify strong signals without distortion, and introduces nearly the lowest amount of unavoidable noise. In principle, the researchers say, design improvements should be able to reduce that noise to the absolute minimum. Versions of the amplifier can be designed to work at frequencies ranging from a few gigahertz to a terahertz (1,000 GHz). For comparison, a gigahertz is about 10 times greater than commercial FM radio signals in the U.S., which range from about 88 to 108 megahertz (1 GHz is 1,000 MHz).

"Our new amplifier has it all," Zmuidzinas says. "You get to have your cake and eat it too."

The team recently described the new instrument in the journal Nature Physics.

One of the key features of the new parametric amplifier is that it incorporates superconductors -- materials that allow an electric current to flow with zero resistance when lowered to certain temperatures. For their amplifier, the researchers are using titanium nitride (TiN) and niobium titanium nitride (NbTiN), which have just the right properties to allow the pump signal to amplify the weak signal.

Although the amplifier has a host of potential applications, the reason the researchers built the device was to help them study the universe. The team built the instrument to boost microwave signals, but the new design can be used to build amplifiers that help astronomers observe in a wide range of wavelengths, from radio waves to X rays.

For instance, the team says, the instrument can directly amplify radio signals from faint sources like distant galaxies, black holes, or other exotic cosmic objects. Boosting signals in millimeter to submillimeter wavelengths (between radio and infrared) will allow astronomers to study the cosmic microwave background -- the afterglow of the big bang -- and to peer behind the dusty clouds of galaxies to study the births of stars, or probe primeval galaxies. The team has already begun working to produce such devices for Caltech's Owens Valley Radio Observatory (OVRO) near Bishop, California, about 250 miles north of Los Angeles.

These amplifiers, Zmuidzinas says, could be incorporated into telescope arrays like the Combined Array for Research in Millimeter-wave Astronomy at OVRO, of which Caltech is a consortium member, and the Atacama Large Millimeter/submillimeter Array in Chile.

Instead of directly amplifying an astronomical signal, the instrument can be used to boost the electronic signal from a light detector in an optical, ultraviolet, or even X-ray telescope, making it easier for astronomers to tease out faint objects.

Because the instrument is so sensitive and introduces minimal noise, it can also be used to explore the quantum world. For example, Keith Schwab, a professor of applied physics at Caltech, is planning to use the amplifier to measure the behavior of tiny mechanical devices that operate at the boundary between classical physics and the strange world of quantum mechanics. The amplifier could also be used in the development quantum computers -- which are still beyond our technological reach but should be able to solve some of science's hardest problems much more quickly than any regular computer.

Read more at Science Daily