Adversarial examples are perturbed inputs designed to fool machine learning models. Adversarial training injects such examples into training data to increase robustness. To scale this technique to large datasets, perturbations are crafted using fast single-step methods that maximize a linear approximation of the model's loss. We show that this form of adversarial training converges to a degenerate global minimum, wherein small curvature artifacts near the data points obfuscate a linear approximation of the loss. The model thus learns to generate weak perturbations, rather than defend against strong ones. As a result, we find that adversarial training remains vulnerable to black-box attacks, where we transfer perturbations computed on undefended models, as well as to a powerful novel single-step attack that escapes the non-smooth vicinity of the input data via a small random step. We further introduce Ensemble Adversarial Training, a technique that augments training data with perturbations transferred from other models. On ImageNet, Ensemble Adversarial Training yields models with strong robustness to black-box attacks. In particular, our most robust model won the first round of the NIPS 2017 competition on Defenses against Adversarial Attacks. However, subsequent work found that more elaborate black-box attacks could significantly enhance transferability and reduce the accuracy of our models.
Researchers have discovered how microscopic imperfections and atomic vibrations can be used to control a powerful quantum effect in an advanced material。 The effect can turn alternating electrical signals from the environment directly into the kind of current electronic devices need, without traditional components。 As temperature changes, the signa
Scientists have created a tiny chip that can generate, steer, and read light-based information all in one device, marking a major leap toward ultra-fast, energy-efficient computing。 The breakthrough uses atomically thin materials and nanoscale structures to control a unique quantum property of light called the “valley” degree of freedom, allowing i
Scientists say moons around rogue planets wandering through the galaxy could remain warm enough for life thanks to tidal heating and hydrogen-rich atmospheres。 These dark, starless worlds may have had stable oceans for billions of years — long enough for complex life to potentially emerge
Researchers at EPFL have developed a chip-scale ultrafast laser that performs on par with traditional tabletop femtosecond lasers。 The innovation could make advanced laser technologies far smaller, cheaper, and more accessible for applications ranging from medical diagnostics to atomic clocks
NASA’s Roman Space Telescope could revolutionize the search for alien worlds by discovering around 100,000 exoplanets—far more than all previous missions combined。 It will look deep into unexplored parts of the Milky Way, helping scientists compare planetary systems across very different galactic environments。 The mission will also uncover rare Ear
NASA’s Psyche spacecraft just used Mars as a giant gravitational slingshot to continue its journey toward a strange metal rich asteroid。 The close flyby boosted the spacecraft’s speed by about 1,000 mph while also producing rare crescent images of Mars glowing through its dusty atmosphere
A stunning spiral galaxy called Messier 88 is racing through the crowded Virgo Cluster on a journey that will dramatically reshape its future。 At its heart lies a supermassive black hole about 100 million times the mass of the Sun, while its graceful spiral arms sparkle with young star clusters and dark clouds of dust。 But as M88 plunges deeper int
For more than a century, pianists and music teachers have argued over whether a performer’s touch can actually change the tone color of a piano note — and now scientists say the answer is yes。 Using a cutting-edge sensor system that tracked piano key movements at 1,000 frames per second, researchers discovered that elite pianists subtly manipulate
Scientists at the University of Houston have shattered a long-standing superconductivity record, creating a material that can conduct electricity with zero resistance at the highest temperature ever achieved under normal pressure conditions。 Their breakthrough pushes superconductivity to 151 Kelvin (minus 122°C), beating a record that stood for mor
NASA’s futuristic X-59 jet is about to face its biggest challenge yet: breaking the sound barrier for the first time。 After a successful series of test flights that pushed the aircraft to near-supersonic speeds, engineers are preparing to fly it faster than Mach 1 and eventually up to Mach 1。6 at 60,000 feet
A long-overlooked organ may hold surprising clues to healthy aging and cancer survival。 Researchers at Mass General Brigham used AI to analyze CT scans from tens of thousands of adults and found that people with healthier thymuses—a small immune-system organ once thought to become largely irrelevant after childhood—lived longer and had substantiall
Scientists in Germany have demonstrated a startling new form of surveillance: identifying people using nothing more than ordinary WiFi signals。 By analyzing how radio waves bounce around a room, researchers can effectively “see” and recognize individuals — even if they are not carrying a device and even if their phone is turned off
Scientists in Finland found bees could solve an insect version of the classic "box-and-banana" problem