搜索结果：Folia

This paper presents a comparative study of near-duplicate image detection techniques in a real-world use case scenario, where a document management company is commissioned to manually annotate a collection of scanned photographs. Detecting duplicate and near-duplicate photographs can reduce the time spent on manual annotation by archivists. This real use case differs from laboratory settings as the deployment dataset is available in advance, allowing the use of transductive learning. We propose a transductive learning approach that leverages state-of-the-art deep learning architectures such as convolutional neural networks (CNNs) and Vision Transformers (ViTs). Our approach involves pre-training a deep neural network on a large dataset and then fine-tuning the network on the unlabeled target collection with self-supervised learning. The results show that the proposed approach outperforms the baseline methods in the task of near-duplicate image detection in the UKBench and an in-house private dataset.

We pose and resolve a seeming paradox about spontaneous symmetry breaking in the quantum theory of infinite systems. For a symmetry to be spontaneously broken, it must not be implementable by a unitary operator. But Wigner's theorem guarantees that every symmetry is implemented by a unitary operator that preserves transition probabilities between pure states. We show how it is possible for a unitary operator of this sort to connect the folia of unitarily inequivalent representations. This result undermines interpretations of quantum theory that hold unitary equivalence to be necessary for physical equivalence.

8 L eight-cylinder generates more than 1,000 hp and 1,000 Nm, Ruf says

Astronomers may have witnessed one of the rarest and most dramatic cosmic events ever seen: a long-sought intermediate-mass black hole ripping apart a dense white dwarf star and devouring it。 The Einstein Probe space telescope caught the explosion in its earliest moments, revealing an unusual sequence of intense X-ray flashes unlike anything seen i

Miners backed by Trump admin sell to Japan, South Korea despite push to develop domestic supply chain

Scientists are raising concerns that we may be overlooking evidence of extraterrestrial life even when it is present。 Hidden biosignatures, limitations in detection technology, and assumptions about what life should look like can all create dangerous false negatives。 The researchers say future missions should focus not only on finding life, but als

A new sunlight-powered material can convert visible light into higher-energy UV light, overcoming a challenge that has frustrated scientists for years。 The breakthrough could enable cleaner air purification, solar-driven chemistry, and advanced manufacturing technologies using nothing more than natural sunlight

What if one of the biggest assumptions in cosmology is wrong。 New research suggests the universe may not be perfectly uniform in every direction, as scientists have long believed。 A puzzling mismatch known as the cosmic dipole anomaly shows that the distribution of distant galaxies and quasars doesn’t align with patterns seen in the leftover glow o

A major breakthrough in quantum technology has turned magnons, tiny magnetic waves once considered too short-lived for practical use, into promising carriers of quantum information。 Researchers extended their lifetime by nearly 100 times, reaching up to 18 microseconds, and discovered that the main limitation is not a law of physics but the purity

The hunt for ancient life on Mars just got an important test run。 Scientists confirmed that the Rosalind Franklin rover's sophisticated instrument can detect subtle differences in two stable molecules that could preserve evidence of past life for billions of years。 But the team also uncovered a surprise: organic molecules in the Murchison meteorite

Water’s odd behavior becomes even more dramatic when it is supercooled, but scientists have struggled to compare the many different ways of describing its microscopic structure。 Researchers at the University of Osaka used an AI model trained on computer simulations to evaluate 16 different structural descriptors。 The system identified the most effe

A new quantum theory bridges two rival models of how impurities behave inside many-particle systems, resolving a problem that has challenged physicists for decades。 The findings could reshape experiments on ultracold atoms, semiconductors, and other exotic forms of quantum matter

Physicists have developed a new optical centrifuge that can precisely spin molecules inside a superfluid for the first time。 The advance could help unravel some of the biggest mysteries of quantum liquids and reveal how superfluidity breaks down at the atomic scale

Android Bench is evolving, and developers can help guide that process

Ancient asteroid impacts may have done more than reshape Earth's surface—they could have helped spark life itself。 New computer models show the collisions created enormous underground hydrothermal systems by cracking the planet's crust and allowing hot water to flow through it。 These long-lasting, life-friendly environments may have covered much of

Astronomers have uncovered 31 of the oldest known quasars, including the two earliest ever detected, shining from a time when the universe was only about 670 million years old。 Powered by supermassive black holes billions of times the Sun’s mass, these incredibly bright objects challenge scientists’ understanding of how such enormous black holes fo

Astronomers have finally cracked the mystery of the famous “Pink Planet,” a strange world 57 light-years away that has puzzled scientists for more than a decade。 Using the James Webb Space Telescope, researchers discovered that its atmosphere contains water vapor, methane, carbon dioxide, ammonia, and something never directly confirmed before in su

An unusual gravitational wave signal has renewed hopes that primordial black holes, long considered purely theoretical, may finally be within reach of discovery。 If confirmed, they could solve one of astronomy's greatest mysteries by explaining the nature of dark matter

Astronomers have released the largest gravitational wave catalog ever, revealing 161 new black hole collisions and pushing the total number of detections to 390。 Among the highlights are the clearest gravitational wave signal ever recorded, the most accurate location of a black hole merger, and growing evidence that some black holes are the product