Technologies
How science is helping unearth an 80-year-old Holocaust mystery
Out of the ruins of the Warsaw Ghetto, remnants of resistance emerge, thanks to advanced geoscientific tools and a team determined to keep the horrors of history from fading.

In a grassy patch of public park in central Warsaw last week, archaeologists dug up a rusted metal coat hook and the tangled chain of a decayed necklace. The objects couldn’t be more ordinary. Or more extraordinary.
The team excavated them from the buried rubble of the Warsaw Ghetto, where German occupiers sealed hundreds of thousands of Poland’s Jews into crowded, desperate squalor during World War II and over 80,000 died inside the walls of starvation, exposure and infectious diseases. Amid the twisted metal and bits of glass, the archaeologists unearthed small, unassuming remnants of daily life, suspended in hardened earth «like a time capsule,» says Philip Reeder, a professor of natural and environmental science at Pittsburgh’s Duquesne University and chief cartographer for the group working on the dig.
A fork. A light-green heart-shaped keepsake. A palm-size silver memorial medallion for a man named Nachum Morgenstern who died in 1880, inscribed in Hebrew.
«It makes you think,» Reeder muses of the tiny heart. «Did it belong to a child who lived in that house and most likely ended up dead when the ghetto was liquidated?»
The excavation — organized by Poland’s Warsaw Ghetto Museum and led by its research specialist Jacek Konik — is part of a broader effort to fill gaps in Holocaust history using geoscientific tools. These include ground-penetrating radar; GPS systems; magnetometers, which study variations in Earth’s geomagnetic field; and electrical resistivity tomography, a technique typically used for engineering and environmental investigations that images subsurface structures down as far as 660 feet (200 meters). Geoscience allows for what’s called «non-invasive archaeology.»
«Archaeology is the most destructive science on Earth,» says Richard Freund, an archaeologist and professor of Jewish studies at Christopher Newport University in Virginia. «What’s good about the geoscience is you don’t destroy anything before you stick a spade in the earth. It’s not very labor intensive and, most importantly, it’s not very expensive.»
Because these advanced tools identify and map historical sites without disturbing human remains, they also enable searches that honor the view held by some that digging up Holocaust graves disrespects the victims.
«It’s a game changer for Holocaust studies,» says Freund. He heads a multidisciplinary geo-archaeological research group aimed at unearthing lost Holocaust history to preserve the past and to protect the future from similar depravity. The group includes Geoscientists Without Borders, a program of the Society of Exploration Geophysicists that applies geoscience to humanitarian efforts.
This summer in Warsaw’s Krasinskich Park, a powerful metal detector turned up an anomaly that Freund’s team thought could be part of the Ringelblum Archive, a vast undercover cache of documents collected by as many as 60 volunteers determined to bear witness to Jewish life in Poland under Nazi occupation. The archive contains tens of thousands of invaluable items that testify to terror and suffering, but also to courage and acts of defiance. Collated in secret, the archive itself represents one such act.
The archive — spearheaded by Warsaw-based Jewish historian and political activist Emanuel Ringelblum starting in fall 1939 when Germany invaded Poland — includes underground newspapers, essays, letters, postcards, diaries, last wills and testaments, tram tickets, ration tickets, Nazi decrees, school schedules and original drawings, literature and poetry by Jewish artists and intellectuals that bring daily life in wartime Warsaw and beyond to vivid life.
In 1946, one of the few survivors of the ghetto guided a search party to metal boxes filled with archive documents amid the ghetto’s ruins. Polish construction workers building new apartments chanced upon two milk cans holding more archive material in 1950. Another milk can has long been rumored — based on diaries like Ringelblum’s — to be hidden at the site of an old brushmaker’s shop near the ghetto’s edge.
The archaeologists had hoped the metal object detected this summer would be that missing piece. Instead, they dug into the rocky earth last week to find a large steel beam collapsed on top of brick walls.
This was a letdown, but still a significant victory, as the other, more subtle artifacts they found carry their own historical and emotional value.
«In many ways it’s a somber experience,» Reeder says of uncovering such everyday relics. «But in many ways it’s an exhilarating experience. You get to tell the stories of people who can’t.»
Freund has led international teams exploring some 30 Holocaust-era sites in Poland, Latvia, Greece and Lithuania. There, researchers have mapped sites of mass burials and used radar and radio waves to uncover a 100-foot (30-meter) hidden escape tunnel leading out of a little-known Nazi extermination site at Ponar forest, known today as Paneriai. Eighty Jewish prisoners dug the tunnel over 76 nights using only their hands and rudimentary tools like spoons.
Just 12 prisoners managed to make it through the escape tunnel to the forest, with 11 surviving to recount constructing the passageway and squeezing through it to avoid massacre. But until Freund’s team found the tunnel, there hadn’t been physical evidence to reinforce the survivors’ accounts.
More than 100,000 people died at Ponar, bullet by bullet, including 70,000 Jews, as well as Poles and Russians. The tunnel’s discovery sheds light on another piece of the story: the tenacity and hope some prisoners still managed to harbor in the most unspeakable circumstances.
«We’re using science to help write or rewrite history,» Reeder says.
Electrical resistivity tomography images the ground’s subsurface by assessing the transition of electrical charges at various depths. Because different materials conduct electricity in different ways, the ERT instrument can delineate between stone, sand, clay, organic material or open voids buried underground. It reports findings back to an attached monitor and, after processing the information with ERT-specific software, generates images that outline the shape of the underground finds.
«There’s nothing it cannot locate,» Freund says.
In July, 21-year-old Christopher Newport University undergraduate Mikaela Martínez Dettinger stood in Krasinskich Park and watched tangible pieces of the past pulled from the ground attached to electricity-conducting metal ERT stakes as passersby rode their bikes and pushed strollers in the afternoon heat.
«The tips of [the stakes] were all stained terracotta orange, and it was because we had literally been hammering them into the rubble of the Warsaw Ghetto factory that was right beneath our feet,» says Martínez Dettinger, a senior studying political science, philosophy and comparative religion who joined Freund in Poland as a research intern this summer.
«I never want to make it sound like I know what it would have been like to be in [ghetto inhabitants’] shoes,» Martínez Dettinger added, «but you can feel in your heart the sorrow or the feelings of anger or persistence these people must have felt.»
Martínez Dettinger, who wants to pursue a career in archaeology, worries her generation doesn’t know enough about Holocaust horrors. She cites a 2020 national survey of Holocaust awareness among American millennials and members of Gen Z from 50 states. Of all survey respondents, 63% didn’t know 6 million Jews were murdered and 36% thought «2 million or fewer Jews» were killed. Of those polled, 48% couldn’t name a single ghetto or concentration camp.
This summer, visiting the most notorious of those camps, Auschwitz, Martínez Dettinger walked the path that prisoners took to the gas chambers where they took their last breaths. And she toured warehouses where prisoners sorted fellow inmates’ suitcases and other personal effects. As she stepped off a gravel path onto the floor of one warehouse, she noticed the sound of her footsteps changing and realized she was standing on hundreds of buttons that had once fastened shirts, possibly like the one she was wearing that day.
With most Holocaust survivors now in their 80s and 90s, fewer and fewer are alive to share their memories. Holocaust deniers distort the facts of the mass extermination or claim it never happened at all. Earlier this month, a Texas school district came under fire after an administrator discussed with teachers the potential need to offer «opposing» views of the Holocaust, based on a new state law that requires teachers to present multiple perspectives when covering «widely debated and currently controversial» issues.
«The science helps prove if atrocities have taken place and can be used to demonstrate war crimes,» says Alastair McClymont, a Calgary-based geophysicist and environmental consultant who joined the Ponar excavation in 2016 and just returned home from working on the Warsaw dig. «Holocaust education helps young people understand how important it is to protect human rights and keep democracies from failing.»
«May this treasure end up in good hands, may it live to see better times. May it alarm and alert the world to what happened,» 19-year-old Dawid Graber, one of the Jewish volunteers who hid the Ringelblum Archive, wrote in his last will and testament.
The Ringelblum Archive isn’t the only trove of eyewitness testimony to survive the Holocaust, but it’s considered the most comprehensive, valuable chronicle of Jewish life in occupied Poland, and a vital piece in the history of Jewish resistance. UNESCO included the archive in its Memory of the World register, alongside the original manuscripts of composer Frederic Chopin and writings by astronomer Nicolaus Copernicus.
Sealed off in November 1940, the Warsaw Ghetto confined more than 350,000 Jews, about 30% of the city’s population, into 2.4% of the city’s total area, or about 1.3 square miles. German SS and police forces liquidated the ghetto in May 1943 following the Warsaw Ghetto Uprising, a monthlong armed revolt of Jewish ghetto residents trying to prevent their deportation to death camps.
Before the ghetto’s obliteration, the archivists — a group code-named Oyneg Shabes («Sabbath pleasure») — strategically hid the archive, divided in three parts to increase the chance at least some of the documents might survive. They also transmitted to the Polish underground all the information they’d recorded about deportations and murders. The underground smuggled the materials out of the country so the free world could learn first-hand of the horrors taking place.
But as Warsaw was rebuilt post-war, some city maps shifted, and that has complicated the search for the archive’s missing piece.
Using subsurface mapping techniques, Freund’s team surmised that the wartime location of the brushmaker’s shop at 34 Świętojerska Street doesn’t correspond with the modern-day 34 Świętojerska Street, where the Chinese embassy now stands — and where another team using traditional archaeology methods already tried, unsuccessfully, to find the missing part of the archive. The geoscientists concluded the old shop can now be found across the street beneath Krasinskich Park, countering long-held assumptions about the best place to search for the lost section of the archive.
«We solved an 80-year-old mystery,» Freund says.
At the end of one long workday in the park this summer, Martínez Dettinger found Freund sitting on an equipment bin, staring transfixed at a section of grass with pink flags stuck in it to indicate scanners had found an object of interest. She asked him a question, but he couldn’t seem to summon the words to answer.
«He could not take his eyes off the piece of grass, and he looked at me and goes, ‘This could be the Ringelblum Archive,'» Martínez Dettinger recalls. «It felt like a moment out of a movie.»
Last week’s excavation might not have produced the cinematic scene the team envisioned, at least not yet. But they hope the Polish government will issue further permits so they can excavate more of the area they’ve identified as the former 34 Świętojerska Street.
«What we were unable to cry and shriek out to the world, we buried in the ground,» the young Dawid Graber wrote. Now that Freund’s team has pinpointed the original location of the brushmaker’s shop, they’re determined to make more silenced voices heard.
«The work,» Freund says, «will continue.»
Technologies
Zelle App Is Gone. Use These Alternatives to Send Money Digitally
You still have lots of free ways to send money to friends and family electronically.

If Zelle has been your go-to app for sending money digitally, it’s time to find a new method. The digital payment app shut down on April 1.
That doesn’t mean you can’t use Zelle altogether, however. Zelle has only discontinued its standalone app. You can still send money using Zelle if your bank belongs to the Zelle network. You’ll just need to do it through your bank’s app or website. You also have other services to choose from. Here’s what you need to know about this change and your options moving forward.
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Why the Zelle app is shutting down
When Zelle launched in 2017, only about 60 US financial institutions offered the service by the end of that year. Today, that number exceeds 2,200. As a result, less than 2% of Zelle transactions occur through the standalone app. Zelle has been phasing out the ability to make transactions on its mobile app since October 2024.
«Today, the vast majority of people using Zelle to send money use it through their financial institution’s mobile app or online banking experience, and we believe this is the best place for Zelle transactions to occur,» Zelle said in an October 2024 press release.
In December, Zelle was in the spotlight when the Consumer Financial Protected Bureau sued the company and three of the largest US banks for failing to protect consumers from widespread fraud on the peer-to-peer payment network. The lawsuit has since been dropped.
Other ways to send money digitally
You can still use Zelle through your bank’s app or website if it belongs to the Zelle network. You can also switch to another digital payment app, such as:
- Apple Wallet
- Cash App
- PayPal
- Venmo
Take some basic precautions when using Zelle or any other digital payment service. These apps are a frequent target for scammers, and Chase Bank has started blocking some Zelle payments it believes could be fraudulent. Only send money to people you know and trust, and watch for red flags like an urgent message claiming to be from your bank or an online ad for concert tickets that seem impossibly cheap.
Technologies
Marvel Rivals Season 2 Starts Next Week, Devs Drop Big News
Emma Frost and Ultron are joining the Rivals roster in season 2, and developers are upping the pace to one new hero per month starting with season 3.

After surviving the endless night in New York City with the Fantastic Four, Marvel Rivals players are getting invited to the shores of Krakoa for the start of season 2 on April 11. The game dropped the first trailer for the new season, giving us our first official look at the new heroes, and a developer vision video dropped major news about the future of hero releases.
The trailer features the former foe and sometimes-leader of the X-Men, Emma Frost, inviting people from across Rivals’ various timelines to the mutant nation of Krakoa, where everyone gets dressed up for a fancy gala — even Wolverine puts on a white tux. The event, however, is unceremoniously interrupted when Ultron shows up preaching extermination.
We also got a look at some of the cosmetics in season 2, though it’s unclear which are from the shop and which might be in the battle pass. In addition to the dressed-up Wolverine, we also got looks at Magik and Psylocke in the traditional X-Men blue and yellow. Nonmutant guests are also getting in on the fun, with fancy attire for heroes like Cap, Widow and Luna Snow.
New Heroes and balance changes in Marvel Rivals Season 2
Emma Frost joins the roster as a Vanguard. We don’t have detailed information about her abilities yet but expect that information to drop ahead of next week’s season launch. Ultron is coming in the season 2.5 update, which should be in late May.
Some team-ups are changing in season 2, including three new team-up abilities that were previewed in the newest developer vision video.
- Emma Frost allows Magneto and Psylocke to create illusions of themselves.
- Doctor Strange teams up with Scarlet Witch allowing her to use small portals to seemingly increase her damage output via a rapid-shooting alternate fire.
- Cap finally teams up with Bucky, allowing the Winter Soldier to leap to allies.
A few existing team-ups are getting adjustments, with Psylocke, Winter Soldier and Doctor Strange being removed from older team-ups in favor of new ones, and Namor moving from working with Luna’s anchor to Hulk’s to empower his ultimate with gamma energy. Two team-ups are being removed entirely: Magneto can no longer team up with Scarlet Witch, and Thor is no longer anchoring Cap and Storm.
The developers vaguely teased other balance changes, including buffs to Peni, Mister Fantastic and Moon Knight, with Strange trading offensive pressure for more survivability and Rocket getting more utility while Loki and Adam Warlock receive nerfs to their Regeneration Domain and Soul Bond abilities.
Future seasons will be shorter, which means more new heroes
One of the most surprising moments in the developer video was the announcement that, beginning with season 3, seasons will be two months long instead of roughly three. There has been a lot of discussion online about whether Rivals’ pace of new heroes (about eight per year based on three-month seasons) was sustainable. Well, apparently the Rivals devs took that personally and are cranking up that pace to a new hero every month, meaning 12 new heroes per year.
This feels borderline ludicrous compared with other hero shooters that average about three new heroes per year, or even MOBAs like League of Legends, which has averaged about four new champions per year over the past five years. Rivals benefits from having an overflowing stable of Marvel characters to pull from rather than inventing their own hero concepts, and compared with Overwatch, the developers seem less worried about mechanical overlap in their heroes, as seen with many support ultimates. Still, a new hero every month feels unheard of for a hero shooter.
New Krakoa map and competitive changes
A new Krakoa-themed domination map is being added in season 2, and Yggsgard: Royal Palace (domination) and Tokyo 2099: Shin-Shibuya (convergence) will rotate out of the map pool for ranked modes, though they’ll still be available in quick play and custom games.
The threshold for competitive picks and bans, which currently only happen in diamond-ranked lobbies, will be lowered to gold 3. Players in Eternity or One Above All ranks will only be able to duo queue, instead of queuing with larger groups — a measure that’s likely intended to keep high-level teams from stomping lobbies.
Speaking of ranks, season 2 will drop everyone by 9 divisions, which is equal to 3 ranks. That means players in Eternity will drop to diamond, and any players at platinum 3 or below will start their climb from bronze 3 again. (AGAIN… AGAIN.)
Rivals developers also announced that individual player performance will be weighted higher when determining competitive progress after a match, meaning if your stats outperform your team’s, you’ll earn more for winning and drop less for losing. This change can help elevate smurfs and other high-skill players in lower-ranked lobbies by getting them into their appropriate ranks faster. However, it can also lead to players stat-farming, instead of playing in a way that is most effective for winning games. Overall, given that Rivals doesn’t use any sort of competitive placement matches, this should be a net positive for the game.
Other announcements
Rivals is adding new skin recolors to certain hero skins and (finally) giving players the option to gift costumes to their friends so they can surprise someone for their birthday, which you definitely did not forget about.
Missions are changing a bit, with the addition of weekly missions and a redistribution of where battle-pass-progressing chrono tokens are earned. The devs framed this as creating a «smoother expectation» of how to earn chrono tokens, but the surface-level description sounds like they’re just making it harder to earn battle pass progress over the season by tucking away more progress under missions with shorter time limits.
The developer vision update also gave us our first look at the competitive distribution, showing how many Rivals players are in each tier as of season 1.5.
The Hellfire Gala trailer says season 2 will start on April 11. While it doesn’t give a specific start time, expect the between-seasons maintenance to finish sometime in the middle of the night in the US.
For more on Marvel Rivals, check out which heroes and roles you should play and how to get free skins.
Technologies
Nintendo Switch 2 vs. Switch 1: Every Detail Compared
The Nintendo Switch 2’s official specs aren’t too different, but the new console has a lot of upgrades on the original Switch.

The Nintendo Switch 2 may look like its predecessor, but there’s been a lot of changes to its features and under the hood. The new console has «10x the graphics performance» compared to the original Switch, says Nvidia, which built the custom processor powering the Switch 2.
The Switch 2, with a release date on June 5, is priced at $450 alone or $500 in a bundle with Mario Kart World, the headliner of the console’s launch games. Here’s all the info on how to preorder the Switch 2.
Note that we’re mostly comparing the Switch 2 to the original Switch 1 released in March 2017, because looping in the Switch Lite and Switch OLED gets complicated.
Design
Broadly, the Switch 2 is a larger version of its predecessor, with everything looking slightly inflated: bigger footprint, bigger screen, bigger Joy-Cons.
Original Switch: The original Switch, with Joy-Cons slotted into the side rails, is a little over 9.4 inches wide, 4 inches tall, a little over half an inch thick and weighs about 10.5 ounces (297 grams). The Joy-Cons slide into place from the top of the device’s sides, while a thin wedge of plastic pops out of the back of the console to serve as a kickstand.
The Switch also came with a dock, which the console could slot into to for recharging and outputting to a TV or large display via HDMI port.
Switch 2: The new Switch 2 is bigger in every way, but it has the same overall shape and layout as the original. The new Joy-Cons will indeed be held in place on the console magnetically, and connect to the console via pins. The new console also sports a wide U-shaped kickstand that spans almost its entire rear width, which can be moved around to prop up the Switch 2 at a variety of angles. Nintendo says the console has more powerful speakers, which we’re looking forward to testing.
The Switch 2’s dock is largely similar in function though it has rounded edges and an internal fan to cool down the console during long game sessions. More importantly, it can output games in 4K to TVs, but only for select games.
Joy-Cons
The Joy-Cons were a marvel when they arrived on the first Switch, and while they’re functionally similar in its successor, there have been upgrades in the Switch 2’s controllers.
Original Switch: The Switch Joy-Cons are simple but powerful controllers that slid on and off the console via plastic rails, connecting and recharging via pins on the side. Detach and they become their own micro-controllers, with little shoulder buttons to boot.
Switch 2: The new console’s Joy-Cons are larger to fit the Switch 2, and lock into the side of the console via powerful magnets — there are small inward-facing buttons to the side of ZR and ZL to detach the controllers from the console. The larger-size Joy-Cons have longer L and R outside shoulder buttons, as well as much wider SL and SR internal shoulder buttons, which are accessible when detached from the console.
And yes, you can use the Switch 2 Joy-Cons as mice by placing their inner edges flat on a surface. During the Nintendo Direct, we saw it being used to control active action games like the wheelchair basketball-simulating DragXDrive and strategy games like Civilization VII.
Display size
Original Switch: The original Switch has a 6.2-inch LCD screen with 1,280×720-pixel resolution, which was reasonably impressive at launch in 2017 but has been outclassed by newer handhelds with sharper displays. The Switch OLED upgraded this with a larger 7-inch display showing deeper blacks and colors, but no upgrade in resolution. The Switch Lite has a 5.5-inch LCD screen.
Switch 2: Unsurprisingly, the Switch 2’s larger size means a larger display. The new console has a 7.9-inch 1080p LCD screen that can get up to 120Hz refresh rate in handheld mode, or up to 4K when docked and outputting to a TV.
Why no OLED display? Possibly to save on costs… or possibly to give Nintendo room to release a Switch 2 OLED version down the line.
CPU/GPU
Original Switch: The original Switch runs on an Nvidia custom Tegra X1 processor split into four ARM Cortex A57 CPU cores, and according to Hackaday, there are four extra A53 cores that aren’t used.
Switch 2: Once again, Nintendo hasn’t released any official info on the Switch 2’s specs, even after the Nintendo Direct reveal stream — and they most the company reveals is that it has a «custom processor made by Nvidia» on the Switch 2’s official specs page. Nvidia confirmed it also has a custom GPU, claiming that the new console has «10x the graphics performance» of the Switch 1, and the custom processor’s AI-powered features include Deep Learning Super Sampling (DLSS), face tracking and background removal for video chat and real-time ray tracing.
We do still have more supposed details from previous leaks. Months ago on X (formerly Twitter), leaker Zuby_Tech posted that the Switch 2’s CPU will be an eight-core Arm Cortex A78C. They also suggested that the GPU will be an Nvidia T239 Ampere, aligning with years of similar rumors reported on by Eurogamer and others about the custom chip, which derives from Nvidia’s Tegra line of chips for smartphones and mobile devices.
RAM and storage
Original Switch. The Switch has 4GB of LPDDR4 RAM and 32GB of onboard storage, expandable up to 2TB via microSD cards in the slot beneath the kickstand.
Switch 2: Even after the reveal stream, Nintendo didn’t release official specs for RAM. Leaker Zuby_Tech posted on X back in September suggesting the Switch 2 will have 12GB of LPDDR5 RAM and 256GB of onboard storage. That leak also suggested the new console will have two internal fans, up from the single one in the original Switch.
Nintendo did confirm that the new console will have 256GB of onboard storage, which can be expanded with special microSD Express cards — sorry, your old Switch-compatible microSD cards won’t work on the Switch 2.
Battery life
Original Switch: The original Switch packs a 4,310-mAh battery, which gives between 4.5 and 9 hours of battery life depending on screen brightness and other factors.
Switch 2: Though Nintendo didn’t release details on the Switch 2’s capacity in the reveal stream, the company does list specs on its website, showing it packs a 5,220mAh battery. While that’s notably larger than the one in its predecessor, Nintendo estimates this will only get players between an estimated 2 and 6.5 hours, depending on games played.
Ports
Original Switch: The first Switch sports a single USB-C port out the bottom, a 3.5mm headphone jack on the top and Wi-Fi 5 plus Bluetooth 4.1 connectivity. On the top is a slot at the top for Switch game cartridges as well as the microSD slot beneath the kickstand on the rear of the console.
Switch 2: The Switch 2 retains the original’s USB-C port on the bottom and 3.5mm jack on the top while adding another USB-C port topside, and now we know what it’s for: to connect with accessories like the Nintendo Switch Camera, a webcam-like camera on a stand to let you do Nintendo’s version of FaceTiming while you play games with your friends.
Nintendo hasn’t clarified the console’s connectivity options, and rumors are scarce on the subject.
As for cartridges, Switch 2 will play some original Switch games in physical versions. The cartridge slot is to the right of the headphone jack in the above image, which is where the slot is on the original Switch. You can tell game cartridges from the two console generations apart by color: ones for the new Switch 2 are red, while older Switch 1 games are black.
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