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Scientists have built the first all-optical photonic time crystal, allowing them to reshape the behavior of terahertz light at extraordinary speeds。 The breakthrough could open the door to ultrafast computing, smarter communication systems, advanced imaging, and a new generation of highly tunable lasers
A new 3D printing technique can produce exceptionally hard tungsten carbide cobalt while using less of its expensive raw materials。 By softening rather than fully melting the material, researchers created defect-free samples with industrial-grade hardness and opened the door to more efficient manufacturing
NASA’s Psyche spacecraft aced its Mars flyby, using the planet’s gravity to speed toward its 2029 encounter with a metal-rich asteroid。 The spacecraft tested its cameras, magnetometer, and particle-detecting instruments, capturing unusual views of Mars and measuring its magnetic environment。 It also detected neutrons from the planet and spotted the
Popular AI-powered food apps may make calorie counting easier, but they may also leave out a surprisingly large part of the meal。 Four apps underestimated calories and fat by about one-third when tested against carefully prepared meals。 High-fat ketogenic dishes appeared to cause the most trouble, while carbohydrates were measured more consistently
Physicists have uncovered a surprising limit to electrical resistance caused by particles colliding。 Using ultracold potassium atoms trapped in a grid of light, researchers created a highly controlled stand-in for electrons moving through a solid。 As collisions became more frequent and intense, resistance initially rose, but eventually hit a ceilin
Photons traveling through a cloud of atoms can emerge so early that they appear to have spent a negative amount of time inside。 Researchers tested whether this was merely a misleading feature of the light pulse by making extremely weak measurements of the atoms。 Surprisingly, the atoms confirmed the same negative dwell time
Scientists have successfully generated electricity with a hydrogen turbine that produces its own pressure through detonation waves instead of relying on a mechanical compressor。 The breakthrough could unlock dramatically more efficient power systems for clean energy and future aviation
A surprisingly simple change could make sodium-ion batteries far more powerful while opening the door to turning seawater into drinking water。 Researchers at the University of Surrey found that sodium vanadium oxide performs much better when its naturally occurring water is left inside instead of being removed during manufacturing
A new hollow nanoreactor mimics living cells to make hydrogen peroxide more efficiently using visible light。 Its light-trapping cavity and proton-shuttling shell could open new possibilities for cleaner chemical manufacturing and artificial photosynthesis
Astronomers may have been listening for alien civilizations in only a small slice of the radio spectrum while overlooking a largely unexplored range of higher frequencies。 Using archived data from the ALMA telescope in Chile, researchers conducted the observatory’s first SETI survey, searching for narrow signals that could indicate advanced technol
Scientists have uncovered new evidence that Venus may still be tearing itself apart from within。 Advanced 3D simulations indicate that some of the planet's giant rift valleys formed relatively recently and could still be expanding。 The results suggest Venus has a far more active interior than researchers once believed, challenging the long-held vie
A black hole observed during a dramatic 2023 eruption did not simply devour gas from its nearby companion star。 It also expelled large amounts of material through powerful jets and winds, even after the outburst had nearly faded。 The results suggest black holes may continue reshaping their surroundings long after their brightest fireworks end
Cosmic expansion allows distant galaxies to move away faster than light, while still letting us see ancient light they emitted when they were much closer。 Eventually, accelerating expansion will push nearly every galaxy beyond our Local Group out of sight, making the Universe appear almost empty
Primordial black holes may occasionally pass through white dwarf stars and trigger enormous Type Ia supernova explosions。 Researchers found that these events could explain chemical patterns seen in supernova remnants, nearby explosions, and stars across the Milky Way