- Micron Unveils The World’s Smallest UFS 4.0 Storage Package At 9 x 13 Millimeters, But It Still Packs Impressive 4,300MB/s Read Speeds Wccftech
- Micron Delivers the World’s Most Compact UFS Package to Enable Next-Generation Phone Designs and Larger Batteries Yahoo Finance
- Micron releases the smallest UFS 4.0 storage chip for smartphones – GSMArena.com news GSMArena.com
- Micron touts beefy HBM chips, and hot DRAM, Samsung’s releasing fresh stacked memory tech too – Blocks and Files Blocks and Files
- PCIe speeds on a fingernail-sized SSD: Micron’s latest UFS 4.0 storage promises to make AI run faster on your smartphone — but you can only get it up to 1TB capacity TechRadar
Tag Archives: smallest
Danish physicists give the gift of world’s smallest Christmas record—in stereo
The first 25 seconds of a classic Christmas song was inscribed into polymer film using the Nanofrazor 3D lithography system.
Physicists at the Technical University of Denmark (DTU) are bringing the Christmas cheer by using a 3D nanolithography tool called the Nanofrazor to cut the smallest record ever. The tune they “recorded,” in full stereo no less: the first 25 seconds of “Rocking Around the Christmas Tree.”
”I have done lithography for 30 years, and although we’ve had this machine for a while, it still feels like science fiction,” said Peter Bøggild, a physicist at DTU. “To get an idea of the scale we are working at, we could write our signatures on a red blood cell with this thing. The most radical thing is that we can create free-form 3D landscapes at that crazy resolution.”
Back in 2015, the same DTU group created a microscopic color image of the Mona Lisa, some 10,000 times smaller than Leonardo da Vinci’s original painting. To do so, they created a nanoscale surface structure consisting of rows of columns, covered by a 20-nm thick layer of aluminum. How much a column was deformed determined which colors of light were reflected, and the deformation in turn was determined by the intensity of the pulsed laser beam. For instance, low-intensity pulses only deformed the columns slightly, producing blue and purple tones, while strong pulses significantly deformed the columns, producing orange and yellow tones. The resulting image fit in a space smaller than the footprint taken up by a single pixel on an iPhone Retina display.
Enlarge / In 2015, the DTU physics group made a nanoscale Mona Lisa with a pixel size of ten nanometers.
DTU Physics
The DTU physics group acquired the Nanofrazor in order to sculpt precisely detailed 3D nanostructures quickly and relatively cheaply. The Christmas record was simply a fun holiday project for postdoc Nolan Lassaline to demonstrate the capability of shaping a surface with nanoscale precision. Instead of adding material to a surface, the Nanofrazor precisely removes material to sculpt the surface into the desired pattern or shape—a kind of gray-scale nanolithography.
“The Nanofrazor was put to work as a record-cutting lathe—converting an audio signal into a spiralled groove on the surface of the medium,” said Bøggild, who is also an amateur musician and vinyl record enthusiast. “In this case, the medium is a different polymer than vinyl. We even encoded the music in stereo—the lateral wriggles is the left channel, whereas the depth modulation contains the right channel. It may be too impractical and expensive to become a hit record. To read the groove, you need a rather costly atomic force microscope or the Nanofrazor, but it is definitely doable.”
The initial goal is to use the Nanofrazor to develop new kinds of magnetic sensors capable of detecting the currents in living brains. Lassaline plans to create “quantum soap bubbles” in graphene in hopes of discovering new ways of precisely manipulating the electrons in that and other atomically thin materials. “The fact that we can now accurately shape the surfaces with nanoscale precision at pretty much the speed of imagination is a game changer for us,” said DTU physicist Tim Booth. “We have many ideas for what to do next and believe that this machine will significantly speed up the prototyping of new structures.”
FTX’s smallest investors may be biggest losers of crypto collapse
Crypto and Web3 have unrealized potential, but the lack of regulation over the years has led to speculative bubbles and Ponzi schemes, Joe Lonsdale says.
Following the collapse of FTX, the cryptocurrency exchange once valued at $32 billion, much of the attention has focused on the now-bankrupt firm’s most prominent investors and celebrity endorsers.
But with more than 1 million creditors, many young people and mom-and-pop investors will be left holding the bag.
A bankruptcy court hearing scheduled for Friday at 10 a.m. EST could shed more light on the full spectrum of those who lost money due to FTX’s implosion. The hearing will consider a motion to release a complete list of FTX’s creditors, including their names and email addresses.
Former Federal Deposit Insurance Corporation (FDIC) chair Sheila Bair recently told Fox Business the real tragedy of the FTX collapse is there are “potentially a million much smaller investors, and proportionately, they’re the ones that are really going to get hurt.”
FTX FRAUD WILL MAKE ‘ENRON LOOK LIKE PEANUTS’: FORMER US ATTORNEY
The logo of FTX is seen at the entrance of the FTX Arena in Miami Nov. 12, 2022. (REUTERS/Marco Bello/File Photo / Reuters Photos)
Bair noted that FTX and the crypto industry at large have marketed heavily to young people and said it “saddens” her that so many who bought into the company’s allure are unlikely to recover their investments.
She suggested that, to prevent a similar future collapse, crypto exchanges should be required to show proof of reserves and that some supervisory enforcement should be put in place.
SAM BANKMAN-FRIED DENIED BAIL IN BAHAMAS, ORDERED HELD UNTIL FEB. 8 IN ALLEGED CRYPTO FRAUD SCHEME
Current FTX CEO John J. Ray III, a corporate restructuring expert who handled the bankruptcy of energy trader Enron, testified before the House Financial Services Committee Tuesday and indicated that customers who put their money into FTX and its affiliates shouldn’t hold out hope for a full recovery of their investments.
“We will never get all these assets back,” Ray said bluntly.
Samuel Bankman-Fried leaves court in Nassau, Bahamas, Tuesday. (Mega for Fox News Digital / Fox News)
In its initial filings during the early stages of its bankruptcy proceedings, FTX indicated it owed its 50 biggest unsecured creditors over $3 billion. At that time, the firm could identify 100,000 creditors that it was aware of, most of whom were customers of FTX.
However, because the bankruptcy of FTX and its more than 130 affiliated entities may also affect former customers and others, the total number of creditors may ultimately rise above 1 million.
WHERE DID THE MONEY GO IN FTX CRYPTO COLLAPSE?
Sam Bankman-Fried, founder and former CEO of FTX Cryptocurrency Derivatives Exchange, speaks during an interview on an episode of Bloomberg Wealth with David Rubenstein in New York Aug 17, 2022. (Jeenah Moon/Bloomberg via Getty Images / Getty Images)
FTX founder and former CEO Sam Bankman-Fried was arrested by authorities in the Bahamas on Monday and is expected to be extradited at a later date.
Federal prosecutors announced Tuesday that Bankman-Fried was indicted on eight charges in the U.S. that carry a combined maximum sentence of 115 years in prison. The charges against him include wire fraud on customers, plus a related conspiracy charge; wire fraud on lenders, plus a conspiracy charge; conspiracies to commit commodities fraud, securities fraud, money laundering and violate campaign finance laws.
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U.S. Attorney for the Southern District of New York Damian Williams said the Bankman-Fried case, which has drawn comparisons to Bernie Madoff’s Ponzi scheme and the Enron scandal, will go down as “one of the biggest frauds in American history.”
Fox Business’ Breck Dumas contributed to this story.
U.S. job growth seen smallest in nearly two years in October, unemployment rate up
WASHINGTON, Nov 4 (Reuters) – U.S. employers likely hired the fewest workers in nearly two years in October and increased wages at a moderate pace, suggesting some loosening in labor market conditions, which would allow the Federal Reserve to shift towards smaller interest rates increases starting in December.
The Labor Department’s closely watched employment report on Friday is also expected to show unemployment ticking up to 3.6% from 3.5% in September. The Fed on Wednesday delivered another 75-basis-point interest rate hike and said its fight against inflation would require borrowing costs to rise further.
But the central bank signaled it may be nearing an inflection point in what has become the fastest tightening of monetary policy in 40 years.
“The labor market is basically OK, but it does seem to be slowing,” said Guy Berger, principal economist at LinkedIn
in San Francisco. “The Fed is going to try to thread the needle where they slow down the labor market enough to put downward pressure on wages and inflation, without causing a recession.”
Nonfarm payrolls likely increased by 200,000 jobs last month after rising 263,000 in September, according to a Reuters survey of economists. That would be the smallest gain since December 2020, when payrolls declined under an onslaught of COVID-19 infections. Estimates ranged from 120,000 to 300,000.
Employment gains were probably almost evenly distributed among industry sectors, in line with recent patterns, with the leisure and hospitality industry leading the way. Leisure and hospitality employment remains below its pre-pandemic level by at least a million jobs. Interest rate-sensitive industries like financial activities as well as transportation and warehousing probably shed jobs as they did in September. Government payrolls are seen declining further.
Hurricane Ian is expected to have put a small dent in payrolls. The storm slammed into Florida in late September and boosted unemployment claims in mid-October, when the government surveyed businesses for last month’s employment report.
“Hurricane Ian should have at least some downward impact on nonfarm payrolls,” said Lou Crandall, chief economist at Wrightson ICAP in Jersey City. “We have lowered our forecast slightly to show an increase of 150,000 (from 200,000) on the assumption that at least some workers were sidelined in the areas hit hardest by the hurricane.”
BACKFILLING POSITIONS
Job growth has remained solid even as domestic demand has softened amid higher borrowing costs because of companies replacing workers who would have left. But with recession risks mounting, this practice could end soon. A survey from the Institute for Supply Management on Thursday found some service industry companies “are holding off on backfilling open positions,” because of uncertain economic conditions.
Still, the labor market remains tight, with 1.9 job openings per unemployed person at the end of September.
Average hourly earnings are forecast to have increased 0.3%, matching September’s gain. But there is a risk of an upside surprise because of Hurricane Ian as well as a calendar quirk. According to Wrightson ICAP’s Crandall, storms and other events that keep people away from work during the payrolls survey week can artificially raise the reported level of hourly earnings.
The government surveys businesses and households during the during the week that includes the 12th day of the month.
“The payroll survey week included the 15th of the month, which tends to bias the month/month change higher, since wage increases secured by those workers paid at mid-month and month-end rather than bi-weekly are more likely to have been captured,” said Kevin Cummins, chief U.S. economist at NatWest Markets in Stamford, Connecticut.
Stripping out any distortions from the weather and calendar quirk, wage growth is cooling. Average hourly earnings are forecast to have increased 4.7% year-on-year in October after rising 5.0% in September. Other wage measures have also come off the boil, which bodes well for inflation.
“We believe we’ve seen wage growth peak,” said Michelle Green, principal economist at Prevedere in Columbus, Ohio. “So while we will continue to see year-over-year growth in average hourly earnings across all private sector employees, the velocity of that growth really is starting to slow down.”
Reporting by Lucia Mutikani; Editing by Cynthia Osterman
Our Standards: The Thomson Reuters Trust Principles.
What is the largest known star in the universe? (What about the smallest?)
As far as stars go, our sun gets a lot of fanfare. Not only does life on Earth literally revolve around it, it dwarfs the rest of the stars in the sky — from our perspective, at least. But if you zoom out to the far reaches of our galaxy, the sun no longer looks like such a giant. In fact, it’s pretty average in size. So what is the largest known star in the universe?
The answer depends on whether you’re talking about mass or the total volume of a star — that is, how much space it takes up, said Phil Massey, an astronomer at the Lowell Observatory in Flagstaff, Arizona. The heaviest stars are often unremarkable when it comes to physical size, and the most voluminous stars are often lightweights. That’s because as stars get older, they tend to expand and shed mass. “It’s like talking about people,” Massey said, “The tallest people may not weigh the most.”
Let’s say you’re talking about mass. The record holder there is the star R136a1, Massey said. It’s located about 160,000 light-years from Earth in the Large Magellanic Cloud, a small galaxy that orbits the Milky Way. In diameter, this star is 30 to 40 times the size of our sun — picture a cherry next to a giant yoga ball that is more than 200 times more massive. This star is also relatively young — roughly 1 million years old compared with our sun’s 4.5 billion years — and “hasn’t done much cooling off or expanding,” according to Massey.
Related: How long do stars live?
If the biggest star in the universe is the one with the largest diameter, there are a number of contenders, Massey said. At the top of that list is UY Scuti (opens in new tab). This red hypergiant’s diameter is roughly 1,700 times that of the sun, according to a 2013 study published in the journal Astronomy and Astrophysics (opens in new tab). If the sun were a cherry, UY Scuti would be a 10-story-high sphere. But there’s a lot of uncertainty in determining the diameter of very distant stars (UY Scuti is about 9,500 lightyears (opens in new tab) from Earth — give or take 1,000 lightyears). To do so, scientists need to know how much light the star produces, a slippery figure due to the fact that stars appear dimmer with distance and brighter close up. Add that to the fact that red hypergiants like UY Scuti are often “variable,” meaning their brightness flickers and flares over time, and you end up with a large margin of error, Massey said.
For example, the authors of the 2013 paper reported that UY Scuti could be up to 192 solar radii — a measurement based on the sun’s radius — larger or smaller than estimated. “The red hypergiants are very messy, and so they’re hard to model,” Massey said. “The surfaces are always in motion.”
Other similarly girthy stars include WOH G64, another red supergiant (less than 5 million years of age according to a 2018 article (opens in new tab)) located in the Large Magellanic Cloud, and VY Canis Majoris (about 8.2 million years old, according to a 2011 article (opens in new tab)), both of which have diameters around 1,500 times that of the sun, Massey said. (And given the uncertainty, either could trump UY Scuti in size.) “Either way, I think it’s incredibly cool,” Massey said. If any of these stars replaced our sun at the center of our solar system, they would envelop every inner planet up to and including Jupiter. “The Earth, all the inner planets would be vaporized,” Massey added.
But while our sun may not be the biggest star in the universe, it’s certainly not the smallest, either. So, what’s the smallest known star? That honor goes to EBLM J0555-57Ab, according to a 2017 study published in the journal Astronomy and Astrophysics (opens in new tab). EBLM J0555-57Ab is smaller than the planet Saturn and barely squeaks by with its star designation, the authors reported. At a lower mass, it wouldn’t be able to sustain nuclear fusion at its core, and would instead be classified as a brown dwarf — a failed star.
Of course, the universe is vast and these stars are just the ones that lie in our immediate cosmic neighborhood. After all, we can’t measure the size of stars at the other side of the Milky Way, much less the far reaches of the universe, Massey said. “There’s too much dust, there’s too much interference with light,” he added. And while UY Scuti and EBLM J0555-57Ab approach the upper and lower limits of a star’s possible size, we still have no idea how massive, or heavy, stars can get, Massey said. “I think there may be some very good surprises.”
Originally published on Live Science.
‘Dark’ black hole wandering the Milky Way is the smallest yet
A rogue black hole wandering the space lanes of our Milky Way galaxy alone could be the smallest black hole yet found, according to one estimate of its mass.
Earlier this year, astronomers led by Kailash Sahu of the Space Telescope Science Institute in Baltimore, Maryland, announced the discovery of the first known isolated stellar-mass black hole.
The black hole is 5,000 light-years away and was discovered thanks to the power of its gravity to act as a gravitational lens, magnifying the light of a background star 19,000 light-years away. It was initially spotted by two ground-based surveys, the Polish-led Optical Gravitational Lensing Experiment (OGLE) which mostly uses the Las Campanas Observatory in Chile, and the Microlensing Observations in Astrophysics (MOA) project at the Mount John University Observatory in New Zealand.
Related: A ‘trove’ of black hole discoveries emerge from dwarf galaxies
Sahu’s team used the Hubble Space Telescope to follow up on the discovery, and the degree of gravitational lensing allowed them to conclude that the black hole has a mass about 7.1 times greater than the sun’s mass.
However, a second team has now come forward with a different mass calculation. The group, led by Casey Lam of the University of California, Berkeley, concluded that the object has a mass between 1.6 and 4.4 times the mass of the sun. If correct, then this could have intriguing implications.
Stellar-mass black holes are the product of the supernovae of stars with masses 20 times greater than the Sun. On the other hand, when stars with between 8 and 20 solar masses go supernovae, they leave behind a neutron star instead.
Neutron stars can theoretically have masses up to about 2.3 solar masses. Observations of stellar-mass black holes detectable in binary systems have not turned up any with less than 5 solar masses, creating a gap between the most massive neutron stars and the least massive black holes. If the black hole is at the upper end of Lam’s mass range, it would help plug this gap. (Several candidate gravitational-wave events have also been detected involving objects that fall into this mass gap.)
“Whatever it is, the object is the first dark stellar remnant discovered wandering through the galaxy unaccompanied by another star,” said Lam in a NASA statement (opens in new tab).
(opens in new tab)
Even though stars with more than 20 solar masses account for just 0.1% of all the stars in the Milky Way, there are so many stars in the Milky Way (an estimated 100–200 billion), and the Milky Way is so old (approximately 13 billion years) that there should now be 100 million or more stellar-mass black holes in our galaxy.
Many of these are found in binary systems, where their presence is evident from their gravitational pull on their companion star and their accretion of matter from their neighbor. One has even been found inside a star cluster, NGC 1850 in the Large Magellanic Cloud. However, many others will be wandering between the stars, going unnoticed until a chance alignment with a background star means we spot them creating a gravitational lens.
This discovery is just the tip of the iceberg. NASA’s Nancy Grace Roman Space Telescope, which is planned for launch in 2027, will survey large swathes of the Milky Way and is expected to identify several thousand microlensing events, many of which could be black holes.
Both papers from Sahu’s team (opens in new tab) and Lam’s team (opens in new tab) are published online.
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Chinese researchers create the world’s smallest transistor gate
Why it matters: Moore’s Law has been on life support for a while now, but it’s not dead yet. Chipmakers are burning the midnight oil to miniaturize transistor designs, and a team of researchers in China have created what is believed to be the smallest one yet.
For several decades, scientists and engineers have been shrinking transistors to the point where their tiniest features are only comprised of tens of atoms. Ever since the first integrated circuits in the 1950s, the rate of progress in miniaturizing transistors has followed Moore’s Law, which predicted the density of active components in integrated chips would double every two years.
As many of our readers know, progress in this direction has slowed down significantly in recent years. The main reason is that we are quickly approaching the physical limits of what’s possible with existing materials and the most advanced manufacturing processes we have.
More specifically, we can’t make transistor gates—which control the flow of current from the source to the drain—much smaller than 5 nm because of something called quantum tunneling that prevents them from working as intended. Materials like graphene and carbon nanotubes might be vital to making transistors even smaller thanks to their physical properties, but getting from there to building functional devices will take a while.
In a paper released this week, Chinese researchers explain they’ve created a transistor with the smallest gate length ever reported. This milestone was made possible by creatively utilizing graphene and molybdenum disulfide and stacking them into a staircase structure with two steps.
On the higher step, you have the source, and on top of the lower one, you have the drain. Both are made of a titanium palladium alloy separated by the surface of the stairs, which is made of a single sheet of a semiconductor material called molybdenum disulfide, itself resting on a layer of hafnium dioxide that acts as an electrical insulator.
The interior of the higher step is a literal sandwich of aluminum covered in aluminum oxide, which rests on top of a graphene sheet—a single layer of carbon atoms. The aluminum oxide acts as an electrical insulator, except for a small gap in the vertical wall of the higher step, where the graphene sheet is allowed to contact the molybdenum disulfide. The entire staircase structure rests on a thick layer of silicon dioxide.
The trick to this design is that the edge of the graphene sheet is used, which means that when the gate is set to the “on” state, it’s only 0.34 nm wide—essentially the width of the graphene layer itself. Another notable feature of this “side-wall transistor” is its negligible current leakage due to higher off-state resistance. Manufacturers could leverage this quality for low-power applications. Best of all, it would be relatively easy to make, although many of the prototypes required quite a bit of voltage to drive.
Also read: ASML’s next-gen EUV machine will give Moore’s Law a new lease of life
Tsinghua University researcher Tian-Ling Ren co-authored the study and said this could be “the last node for Moore’s law.” He also believes going smaller than 0.34 nm for the gate size is almost impossible.
Of course, the researchers behind the new transistor only proved that a functional transistor could be made using one-atom thin materials without inventing a new process for precision positioning of the required layers. Reliably building billions of these side-wall transistors is still a distant dream but is a critical step in that direction, which fuels hope for faster, more power-efficient devices in the future.
In the meantime, Samsung, Intel, and TSMC are working hard on making gate-all-around (GAA-FET) transistors a reality and standardizing interconnects for chiplet designs.
New Part Day: Smallest ARM MCU Uproots Competition, Needs Research
We’ve been contacted by [Cedric], telling us about the smallest MCU he’s ever seen – Huada HC32L110. For those of us into miniature products, this Cortex-M0+ package packs a punch (PDF datasheet), with low-power, high capabilities and rich peripherals packed into an 1.6mm x 1.4mm piece of solderable silicon.
This is matchstick head scale computing, with way more power than we previously could access at such a scale, waiting to be wrangled. Compared to an ATTiny20 also available in WLCSP package, this is a notable increase in specs, with a way more powerful CPU, 16 times as much RAM and 8-16 times the flash! Not to mention that it’s $1 a piece in QTY1, which is about what an ATTiny20 goes for. Being a 0.35mm pitch 16-pin BGA, your typical board house might not be quite happy with you, but once you get a board fabbed and delivered from a fab worth their salt, a bit of stenciling and reflow will get you to a devboard in no time.
Drawbacks? No English datasheet or Arduino port, and the 67-page PDF we found doesn’t have some things like register mappings. LILYGO promised that they will start selling the devboards soon, but we’re sure it wouldn’t be hard for us to develop our own. From there, we’d hope for an ESP8266-like effect – missing information pieced together, translated and made accessible, bit by bit.
When it comes to soldering such small packages, we highly recommend reflow. However, if you decide to go the magnet wire route, we wouldn’t dare object – just make sure to send us pictures. After all, seems like miniature microcontrollers like ATTiny20 are attractive enough of a proposition that people will pick the craziest route possible just to play with one. They say, the madness of the brave is the wisdom of life.
We thank [Cedric] for sharing this with us!
Some Of Steam’s Biggest (And Smallest) Discounts Are Going Away
At the end of March, Valve is making changes to the way studios and publishers can offer their games at a discount on Steam, which sounds like a minor administrative thing is also something the more financially-savvy Steam game purchasers among you might want to keep an eye on.
Published earlier this month, a backend blog post called Discount Rule Changes says that as of March 28, Valve will be “changing some rules for discounts”, with the main ones being a revised “discount cooldown” period and the removal of the ability for developers and publishers to “discount a product by more than 90% or less than 10%.”
While it’s easy to look at a move like the latter and feel like it’s a little unfair for users, every change being made is clearly being done to stop those responsible for a game’s pricing—and we’re talking everyone from the dodgiest little scam game to the biggest AAA publishers—from not only gaming Steam’s algorithm to make their releases more prominent, but also trick users into thinking a sale is bigger than it actually is by artificially inflating the original, pre-discount price.
The specifics of the changes are:
– You can run a launch discount, but once your launch discount ends, you cannot run any other discounts for 28 days.
– It is not possible to discount your product for 28 days following a price increase in any currency.
– Discounts cannot be run within 28 days of your prior discount, with the exception of Steam-wide seasonal events.
– Discounts for seasonal sale events cannot be run within 28 days of releasing your title, within 28 days from when your launch discount ends, or within 28 days of a price increase in any currency.
– You may not change your price while a promotion is live now or scheduled for the future.
– It is not possible to discount a product by more than 90% or less than 10%.
– Custom discounts cannot last longer than two weeks, or run for shorter than 1 day.
Will this actually work? Who knows! But it sure looks more robust on paper, at least.
Atomic Clocks Experiment Reveals Time Dilation at The Smallest Scale Ever
In his theory of general relativity, Einstein predicted something called time dilation: the notion that two clocks under two different gravitational pulls will always tick at different speeds.
The effect has been observed in many experiments since, but now scientists have recorded it at the smallest scale seen so far.
The result was achieved using ultra-precise atomic clocks just a millimeter (0.04 inches) apart – about the width of a sharp pencil tip. Collecting 90 hours of data gave the team a reading that was 50 times more precise than any previous similar measurement.
And of course the smaller and more precise the scale, the more we rely on quantum mechanics to explain what’s going on. The researchers are hoping that their new readings open up a way to learning more about how the curvature of spacetime – what we experience as gravity – affects the characteristics of particles according to quantum physics.
“The most important and exciting result is that we can potentially connect quantum physics with gravity, for example, probing complex physics when particles are distributed at different locations in the curved space-time,” says physicist Jun Ye from the University of Colorado Boulder.
In this experiment, the researchers used what’s known as an optical lattice, a web of laser light used to trap atoms in place so they can be observed. It’s a technique used for the latest generation of atomic clocks, offering more precision in timekeeping through the laser light waves, and these lattices can be used for quantum simulations too.
Here, the two atomic clock readings were taken from the same cloud of atoms, in a highly controlled energy state. In fact, the atoms ticked between two energy levels in perfect synchronization for 37 seconds, a record in terms of quantum coherence (that is, keeping quantum states stable) – and that stability is essential for these measurements.
That enabled the scientists to take their readings at two separate points, measuring the redshift across the cloud of about 100,000 ultracold strontium atoms. The redshift shows the change in the frequency of the atoms’ radiation along the electromagnetic spectrum – or in other words, how quickly the atomic clock is ticking.
While the difference in redshift across this tiny distance was just 0.0000000000000000001 or so, that’s in line with predictions made by general relativity. Those differences can make a difference when you get out to the scale of the entire Universe, or even when you’re dealing with systems that need to be ultra-accurate, such as GPS navigation.
“This is a completely new ballgame, a new regime where quantum mechanics in curved space-time can be explored,” says Ye.
“If we could measure the redshift 10 times even better than this, we will be able to see the atoms’ whole matter waves across the curvature of space-time. Being able to measure the time difference on such a minute scale could enable us to discover, for example, that gravity disrupts quantum coherence, which could be at the bottom of why our macroscale world is classical.”
Part of what makes this time dilation research so exciting is that it points the way towards atomic clocks that are even more precise in the future, giving scientists a blueprint that can be refined to take measurements on smaller and smaller scales.
Atomic clocks have come a long way in the last few decades, and there’s plenty more to come.
The research has been published in Nature.