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Alienware redesigns m15, m17 gaming laptops, adds ninth-generation Intel Core processors



Alienware m15 gaming laptop

Gaming laptops were once barely able to live up to their “laptop” moniker — too big and hot to use on laps and too heavy to be very mobile. Those days are mostly over, however, as technological advances have allowed gaming notebooks to slim down and cool off without sacrificing power.

The latest example of this evolution comes from Alienware, Dell’s longtime gaming brand, which just launched redesigned versions of its m15 and m17 laptops that the company says are its thinnest 15-inch and 17-inch laptops ever. Despite that claim, the new notebooks still pack enough performance punch to keep gamers happy.

While they won’t be confused with a MacBook, the new m15 and m17 have dieted down to to 4.7 pounds and 5.8 pounds, respectively, thanks to a rebuild based on Alienware’s Legend design DNA (first seen earlier this year on its Area 51 laptop). Other design enhancement include a revamped keyboard design and larger glass track pad, plus some intriguing display options. In addition to 144Hz, 240Hz, and OLED screen options, the m15 is the first laptop that can be equipped with Tobii eye-tracking technology, while the m17 is the first that can ship with an Eyesafe display that limit blue light emissions.

The new systems wouldn’t be Alienwares, however, if they didn’t include the latest and greatest internal components, and the m15 and m17 are no exceptions. They can be configured with Intel’s ninth-generation Core processors, along with the latest GPU options from Nvidia — including the new GeForce GTX 1660 Ti and RTX 2060, 2070 and 2080 cards. Both laptops include either 8GB or 16GB of RAM, and to help keep things slimmer, they are only offered with solid-state drives (256GB and up) .To handle the heat version 3.0 of Alienware Cyro-Tech will increase airflow by at least 20 percent more than the last m15 and m17 editions.

The refreshed versions of the m15 and the m17 will become available to order on June 11, with a starting price of $1,499 for a base configuration of either size. 

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Study: Solitary electric eels sometimes hunt in groups with synchronized zaps



Volta’s electric eels can gather in groups, working together to corral smaller fish in shallower waters, a new study finds. Then, smaller groups of about 10 eels attack in unison with high-voltage discharges.

Electric eels were long believed to be solitary predators, preferring to hunt and kill their prey alone by sneaking up on unsuspecting sleeping fish at night and shocking them into submission. But according to a recent paper published in the journal Ecology and Evolution, there are rare circumstances in which eels employ a social hunting strategy instead. Specifically, researchers have observed more than 100 electric eels in a small lake in the Brazilian Amazon River basin forming cooperative hunting parties to capture small fish called tetras.

“This is an extraordinary discovery,” co-author C. David de Santana, of the Smithsonian National Museum of Natural History, said. “Nothing like this has ever been documented in electric eels. Hunting in groups is pretty common among mammals, but it’s actually quite rare in fishes. There are only nine other species of fishes known to do this, which makes this finding really special.”

Electric eels are technically knife fish. The eel produces its signature electric discharges—both low and high voltages, depending on the purpose for discharging—via three pairs of abdominal organs comprised of electrocytes, located symmetrically along both sides of the eel. The brain sends a signal to the electrocytes, opening ion channels and briefly reversing the polarity. The difference in electric potential then generates a current, much like a battery with stacked plates.

Enlarge / Multiple Volta’s electric eels attack as a group, shocking fish out of the water and into a stupor so that they can easily be eaten.

Douglas Bastos

This isn’t the first time researchers have made surprising discoveries about electric eels. For instance, the 19th-century physicist Michael Faraday conducted several experiments with electric eels in 1838. He noted that he only felt mild shocks because the water dissipated the discharges so quickly. Vanderbilt University biologist and neuroscientist Kenneth Catania is one of the most prominent scientists studying electric eels these days. He has found that the creatures can vary the degree of voltage in their electrical discharges, using lower voltages for hunting purposes, and higher voltages to stun and kill prey. Those higher voltages are also useful for tracking potential prey, akin to how bats use echolocation.

And in 2016, Catania reported evidence in support of Alexander von Humboldt’s 1800 account of how Venezuelan natives at the time used wild horses to lure and trap electric eels (“horse fishing”). The stamping and snorting of horses in the shallow waters favored by electric eels caused the latter to leap up and stun the horses with a series of high-voltage electric discharges as a defense mechanism. Once the eels were exhausted, the natives could catch them easily using small harpoons on ropes.

For centuries, naturalists dismissed Humboldt’s account, because nobody since had noted such behavior—until Catania spotted eels in his lab reacting much like Humboldt’s description to the sight of the net used to transfer the eels from their cages to the chamber Catania used for experiments. He conducted experiments with LEDs mounted on a fake alligator head (outfitted with conductive tape to visualize the discharges). The eels aggressively attacked the fake alligator head just as described by Humboldt. Catania believes the response kicks in under certain conditions, such as when eels are stranded in small bodies of water with the sudden arrival of the dry season.

Until 2019, scientists thought that the electric eel was the only species in its particular genus. That was the year de Santana published a paper effectively tripling the number of known species of electric eels. Among those was the subject of the current paper: Volta’s electric eel (Electrophorus voltai).

“An individual of this species can produce a discharge of up to 860 volts, so in theory if 10 of them discharged at the same time, they could be producing up to 8,600 volts of electricity,” said de Santana. “That’s around the same voltage needed to power 100 light bulbs.” He has been shocked several times in the field and notes that, while it only lasts a fraction of a second, a shock can still cause painful muscle spasms.

Schematic illustration of the stages involved in the social predation observed in electric eels.
Enlarge / Schematic illustration of the stages involved in the social predation observed in electric eels.

D.A. Bastos et al., 2021

De Santana and his co-authors first noticed the unusual group hunting behavior on a 2012 field expedition to explore the diversity of fish of the Iriri River, when team member (and co-author) Douglas Bastos found a small lake packed with over 100 electric eels. A second expedition in 2014 found a similarly sized group in the same location, and the team would ultimately log some 72 hours of continuous observation, recording the eels’ behavior.

Most of the time, the eels just hung out in the deeper end of the lake, occasionally surfacing to breathe. But the eels became active at dusk and dawn. De Santana’s team noted how the eels would work together to herd schools of tetras into a densely packed areas in the shallow waters, by swimming in a large circle to create the equivalent of a corral. Then the eels spit into smaller hunting parties of about 10 eels, surrounding the ball of tetras and stunning the small fish with synchronized high-voltage discharges. That made it very easy to snap up the stunned tetras.

“This is the only location where this behavior has been observed, but right now we think the eels probably show up every year,” said de Santana. “Our initial hypothesis is that this is a relatively rare event that occurs only in places with lots of prey and enough shelter for large numbers of adult eels.” If the behavior were commonplace, he reasoned, it would have come up in their interviews with the locals.

De Santana and his team will continue their investigation of this unusual behavior; they are hoping to make direct measurements of the synchronized discharges on their next expedition. And they have a launched a citizen scientist program called Project Poraque to track down additional packs of electric eels in the region. The team will also collect eight to 10 adult eels and bring them to a lab in Germany, the better to study them under more controlled settings.

DOI: Ecology and Evolution, 2021. 10.1002/ece3.7121 (About DOIs).

Listing image by L. Sousa

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Virgin Orbit just earned the orbit part of its name



Enlarge / LauncherOne heads to orbit after dropping from its carrier aircraft on Sunday.

Virgin Orbit

On Sunday afternoon, Virgin Orbit joined the rare club of companies that have privately developed a rocket and successfully launched it into orbit. Moreover, with its LauncherOne rocket dropped from a 747 aircraft, the California-based company has become the first to reach orbit with an air-launched, liquid-fueled rocket.

“This magnificent flight is the culmination of many years of hard work and will also unleash a whole new generation of innovators on the path to orbit,” said Sir Richard Branson, the founder of the company. “Virgin Orbit has achieved something many thought impossible.”

Sunday’s flight, which included multiple firings of LauncherOne’s upper stage engine and successful deployment of several small satellites for NASA, caps a development program that has spanned about eight years and myriad technical challenges.

An air-launched rocket has some advantages over traditional boosters launched from the ground, most notably flexibility in reaching different orbits and the ability to take off in fairly inclement weather. However, to obtain these benefits, Virgin Orbit had to design a liquid-fueled rocket that could be dropped horizontally from an aircraft, ignite its engines, and rapidly orient itself into a more vertical trajectory. (Although Orbital Sciences developed the Pegasus rocket to drop from a carrier aircraft in the late 1980s, it was a more straightforward design using solid propellant.)

A rocket dropped from an aircraft cannot ignite its engines immediately due to the proximity of the plane and its pilots. In the case of LauncherOne, the rocket’s NewtonThree engine is ignited 3.25 seconds after being dropped. Main engine start comes at 5.2 seconds. During this time, the rocket is falling and losing the velocity it gained from the aircraft at about 30,000 feet.

Technical challenges

Due to this drag, a negative acceleration acts on the booster, causing all sorts of problems for both the rocket’s structure and its propulsion system. One problem is that this begins to force the liquid oxygen and kerosene propellants to the top of the tanks and the ullage gas—which fills the tanks as propellant is expended—toward the engine inlet.

The ignition process itself is also a challenge in the air. On the ground, a rocket typically ignites its engines, and the onboard computer performs a final, quick check to make sure everything is healthy, before the rocket is released. This is why liftoff typically follows ignition by a few seconds. There is no margin for error with Launcher One, because if ignition does not happen, the rocket simply falls into the ocean.

Image showing ignition of LauncherOne after being dropped by its <em>Cosmic Girl</em> aircraft.

Image showing ignition of LauncherOne after being dropped by its Cosmic Girl aircraft.

Virgin Orbit

The company and its engineers were able to overcome all of these issues and more with the design of their rocket. But it took time and a lot of money. Branson has acknowledged that he and other investors have put about $1 billion into Virgin Orbit, which is a lot of money to invest in a small satellite launcher, however innovative it could be. Ars explored Virgin Orbit’s pathways toward profitability last year, and the road will not be easy.

But those are discussions for another day. On Sunday, Virgin Orbit reached orbit on just its second flight, with what appeared to be a pretty much flawless mission. Few companies have done this with privately developed vehicles—very few indeed beyond Orbital Sciences, SpaceX, and Rocket Lab. It was a good day.

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A curious observer’s guide to quantum mechanics, pt. 2: The particle melting pot



One of the quietest revolutions of our current century has been the entry of quantum mechanics into our everyday technology. It used to be that quantum effects were confined to physics laboratories and delicate experiments. But modern technology increasingly relies on quantum mechanics for its basic operation, and the importance of quantum effects will only grow in the decades to come. As such, physicist Miguel F. Morales has taken on the herculean task of explaining quantum mechanics to the rest of us laymen in this seven-part series (no math, we promise). Below is the second story in the series, but you can always find the starting story here.

Welcome back for our second guided walk into the quantum mechanical woods! Last week, we saw how particles move like waves and hit like particles and how a single particle takes multiple paths. While surprising, this is a well-explored area of quantum mechanics—it is on the paved nature path around the visitor’s center.

This week I’d like to get off the paved trail and go a bit deeper into the woods in order to talk about how particles meld and combine while in motion. This is a topic that is usually reserved for physics majors; it’s rarely discussed in popular articles. But the payoff is understanding how precision lidar works and getting to see one of the great inventions making it out of the lab, the optical comb. So let’s go get our (quantum) hiking boots a little dirty—it’ll be worth it.

Two particles

Let’s start with a question: if particles move like waves, what happens when I overlap the paths of two particles? Or said another way, do particle waves only interact with themselves, or do they mix together?

Enlarge / On the left is the interferometer from last week, where a single particle is split by the first mirror and takes two very different paths. On the right is our new setup where we start with particles from two different lasers and combine them.

Miguel Morales

We can test this in the lab by modifying the setup we used last week. Instead of splitting the light from one laser into two paths, we can use two separate lasers to create the light coming into the final half-silvered mirror.

We need to be careful about the lasers we use, and the quality of your laser pointer is no longer up to the task. If you carefully measure the light from a normal laser, the color of the light and the phase of the wave (when the wave peaks occur) wander around. This color wander is not discernible to our eyes—the laser still looks red—but it turns out that the exact shade of red varies. This is a problem money and modern technology can fix—if we shell out enough cash we can buy precision mode-locked lasers. Thanks to these, we can have two lasers both emitting photons of the same color with time-aligned wave crests.

When we combine the light from two high-quality lasers, we see exactly the same stripey pattern that we saw before. The waves of particles produced by two different lasers are interacting!

So what happens if we again go to the single photon limit? We can turn the intensity of the two lasers down so low that we see the photons appear one at a time on the screen, like little paintballs. If the rate is sufficiently low, only one photon will exist between the lasers and the screen at a time. When we perform this experiment we will see the photons arrive at the screen one at a time; but when we look at the accumulated pointillism painting, we will see the same stripes we saw last week. Once again, we’re seeing single particle interference.

It turns out that all the experiments we performed before give exactly the same answer. Nature does not care if one particle is interacting with itself or if two particles are interacting with each other—a wave is a wave, and particle waves act just like any other wave.

But now that we have two precision lasers, we have a number of new experiments we can try.

Two colors

First, let’s try interfering photons of different colors. Let’s take the color of one of the lasers and make it slightly more blue (shorter wavelength). When we look at the screen we again see stripes, but now the stripes walk slowly sideways. Both the appearance of stripes and their motion are interesting.

First, the fact that we see stripes indicates that particles of different energy still interact.

The second observation is that the striped pattern is now time dependent; the stripes walk to the side. As we make the difference in color between the lasers larger, the speed of stripes increases. The musicians in the audience will already recognize the beating pattern we are seeing, but, before we get to the explanation, let’s improve our experimental setup.

If we are content to use narrow laser beams, we can use a prism to combine the light streams. A prism is usually used to split a single light beam and send each color in a different direction, but we can use it backwards and with careful alignment use the prism to combine the light from two lasers into a single beam.

The light from two lasers with different color combined with a prism. After the prism the light ‘beats’ in intensity.
Enlarge / The light from two lasers with different color combined with a prism. After the prism the light ‘beats’ in intensity.

Miguel Morales

If we look at the intensity of the combined laser beam, we will see the intensity of the light ‘beat.’ While the light from each laser was steady, when their beams with slightly different colors are combined, the resulting beam oscillates from bright to dim. Musicians will recognize this from tuning their instruments. When the sound from a tuning fork is combined with the sound of a slightly out-of-tune string, one can hear the ‘beats’ as the sound oscillates between loud and soft. The speed of the beats is the difference in the frequencies, and the string is tuned by adjusting the beat speed to zero (zero difference in frequency). Here we are seeing the same thing with light—the beat frequency is the color difference between the lasers.

While this makes sense when thinking about instrument strings, it is rather surprising when thinking of photons. We started with two steady streams of light, but now the light is bunched into times when it is bright and times when it is faint. As the difference between the colors of the lasers is made larger (they’re de-tuned), the faster the pulsing becomes.

Paintballs in time

So what happens if we again turn down the lasers really low? Again we see the photons hit our detector one at a time like little paintballs. But if we look carefully at the timing of when the photons arrive, we see that it is not random—they arrive in time with the beats. It does not matter how low we turn the lasers—the photons can be so rare that they only show up one every 100 beats—but they will always arrive in time with the beats.

This pattern is even more interesting if we compare the arrival time of the photons in this experiment with the stripes we saw with our laser pointer last week. One way of understanding what is happening in the two-slit experiment is to picture the wave nature of quantum mechanics directing where the photons can land side to side: the paintballs can hit in the bright regions and not in the dark regions. We see a similar pattern in the paintball arrival in the two-color beam, but now the paintballs are being directed forward and back in time and can only hit in time with the beats. The beats can be thought of as stripes in time.

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