Science

Overall, men were faster than women in all split disciplines, with the highest sex difference in cycling and the smallest in running. The analysis revealed significant differences in both cycling and running times among athletes. The variability in cycling times indicates diverse pacing strategies and endurance levels, while the running times further highlight the individual performance dynamics of the athletes. The results illustrate how variability in pacing affects cumulative performance and final rankings.

A statistical analysis found that the number of fake journal articles being churned out by “paper mills” is doubling every year and a half.

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The Study, published in PNAS: The entities enabling scientific fraud at scale are large, resilient, and growing rapidly

cross-posted from: https://lemmy.sdf.org/post/39861120

Chinese students at UK universities are being pressured to spy on their classmates in an attempt to suppress the discussion of issues that are sensitive to the Chinese government, a new report suggests.

The UK-China Transparency (UKCT) think tank says its survey of academics in China studies also highlighted reports of Chinese government officials warning lecturers to avoid discussing certain topics in their classes.

It comes days after a new law came into force placing more responsibility on universities to uphold academic freedom and free speech.

The Chinese embassy in London called the report "groundless and absurd", adding that China respects freedom of speech in the UK and elsewhere.

The regulator, the Office for Students (OfS), says freedom of speech and academic freedom are "fundamental" to higher education.

The new legislation, which came into force last week, says universities should do more to actively promote academic freedom and freedom of speech, including in cases where institutions have agreements in place with other countries.

Universities could be fined millions if they fail to do so, the OfS has said.

However, the UKCT report says some universities are reluctant to address the issue of Chinese interference because of their financial reliance on Chinese student fees.

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Recent breakthroughs show that quantum systems can exhibit reversibility in ways previously thought impossible, challenging our understanding of time's arrow and irreversibility.

In 2025, researchers at the University of Surrey demonstrated that two arrows of time can emerge simultaneously in quantum systems. "While our common experience tells us that time only moves one way, we are just unaware that the opposite direction would have been equally possible," explains Dr. Andrea Rocco, lead author of the study[^1].

The key insight comes from examining open quantum systems - those that interact with their environment. While classical physics suggests processes like spilled milk spreading across a table must be irreversible, quantum mechanics operates differently. Even after applying standard simplifying assumptions, the equations describing quantum systems behave the same way whether moving forward or backward in time[^1].

This theoretical work gained experimental validation in July 2025 through a breakthrough "entanglement battery" that allows physicists to manipulate quantum entanglement reversibly[^2]. Just as a regular battery stores energy, this quantum device can store and release entanglement while preserving the total amount, enabling previously impossible reversible transformations of quantum states.

However, this reversibility has strict limits. According to physicist Thomas Guff, it only works when specific mathematical conditions are met - particularly that a "memory kernel" remains symmetrical in time[^3]. The reversal also becomes impossible if an observer retains information about measurement outcomes, as this resets the initial conditions within that observer's branch of the universe[^4].

[^1]: Cosmos Magazine - Theoretical physicists show that quantum systems have opposing arrows of time

[^2]: Science Daily - Breakthrough battery lets physicists reverse entanglement

[^3]: EurekAlert - Physicists uncover evidence of two arrows of time emerging from the quantum realm

[^4]: Physics Stack Exchange - Where does the irreversibility came from if all the fundamental interaction are reversible?