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  • Noise can make quantum circuits effectively shallow

    What the study found

    The study finds that uncorrected local noise can effectively shorten quantum circuits to logarithmic depth when estimating observable expectation values. It also finds that quantum circuits under any non-unital noise do not exhibit barren plateaus for cost functions made from local observables.

    Why the authors say this matters

    The authors conclude that, unless quantum circuits are carefully designed to take advantage of noise, noisy quantum computers are unlikely to beat shallow ones for algorithms that estimate observable expectation values. They also note that this is relevant to many variational quantum machine learning proposals.

    What the researchers tested

    The researchers studied the effect of uncorrected local noise on logical quantum circuits, motivated by near-term hardware without successful fault-tolerant quantum error correction. They analyzed observable expectation values, non-unital noise, and cost functions composed of local observables, and they also designed a classical algorithm for estimating expectation values.

    What worked and what didn't

    For observable expectation values, the authors show that noise effectively truncates most quantum circuits to logarithmic depth. They prove that non-unital noise removes barren plateaus for local-observable cost functions, and they also obtain an efficient classical algorithm that estimates expectation values within any constant additive accuracy with high probability over the choice of circuit, for any circuit architecture.

    What to keep in mind

    The abstract does not describe experimental data or a specific hardware implementation. The results apply to the setting studied here: noisy quantum circuits, observable expectation values, local observables, and the stated noise conditions.

    • Uncorrected local noise can effectively reduce many quantum circuits to logarithmic depth for expectation-value estimation.
    • Quantum circuits under any non-unital noise do not exhibit barren plateaus for cost functions built from local observables.
    • The authors designed a classical algorithm that estimates expectation values within any constant additive accuracy with high probability.
    • The study suggests noisy quantum circuits are unlikely to outperform shallow ones for many expectation-value-based algorithms.

  • Milky Way circular velocity curve measured from element abundances

    What the study found

    The study presents a new data-driven method for measuring the Milky Way’s circular velocity curve by using gradients in stellar element abundances. The authors report a circular velocity at the solar radius of 235.3 km s−1 from the [Mg/Fe] abundance ratio, along with estimates of the radial and azimuthal frequencies and the Oort constants.

    Why the authors say this matters

    The findings indicate that abundance ratios can trace stellar positions and motions in the Galactic disk, which the authors say enables an empirical measurement of the Galaxy’s circular velocity curve, epicyclic frequency, and azimuthal frequency. The study suggests this provides a way to study kinematic gradients across the Milky Way’s disk.

    What the researchers tested

    The researchers combined stellar surface abundances from the APOGEE survey with kinematic data from the Gaia mission. They tested a method that uses element abundance gradients in the plane of radial kinematics, focusing on average [Fe/H] and [Mg/Fe] patterns in the Milky Way disk.

    What worked and what didn't

    The results confirm ordered structure in the Milky Way’s disk in terms of average [Fe/H] and [Mg/Fe]. The authors suggest that 〈[Fe/H]〉 traces the radial positions of stars in the disk, while 〈[Mg/Fe]〉 traces orbital excursions around that radius. The method produced estimates of v_c,⊙ = 235.3−3.7+2.8 km s−1, κ0,R⊙ = 36.9−1.0+0.8 km s−1 kpc−1, Ω0,R⊙ = 28.5−0.1+0.4 km s−1 kpc−1, and Oort constants A = 16.5−0.1+0.1 km s−1 kpc−1 and B = −11.9−0.3+0.1 km s−1 kpc−1.

    What to keep in mind

    The abstract provided does not describe major limitations, but the reported measurements are tied to the solar radius and to the abundance ratio [Mg/Fe] as the most constraining tracer. The summary also stops before giving the full expression for the radial acceleration at the solar radius.

    • A new data-driven method uses stellar element abundance gradients to measure the Milky Way’s circular velocity curve.
    • APOGEE abundance data and Gaia kinematics were combined in the analysis.
    • Average [Fe/H] and [Mg/Fe] show ordered structure across the Milky Way’s disk.
    • The study reports v_c,⊙ = 235.3 km s−1 from [Mg/Fe] at the solar radius.
    • The authors also estimate the radial and azimuthal frequencies and the Oort constants.

  • Problematic short-form video users show more impulsive decisions

    What the study found

    The study found that problematic short-form video users showed weaker inhibitory control than matched controls. The authors link this to a more impulsive decision-making pattern, rather than to abnormal information accumulation or response bias.

    Why the authors say this matters

    The authors suggest these findings help explain the cognitive processes behind inhibitory control deficits in problematic short-form video users. They also state that the study offers novel implications for intervention in behavioral addictions.

    What the researchers tested

    The researchers compared 30 problematic short-form video users with 28 matched controls. Participants completed a go/no-go task, which measures the ability to withhold a response, and a contingency degradation task, which assesses habitual tendencies; the go/no-go data were analyzed with a drift-diffusion model, or DDM, to estimate latent information-processing mechanisms.

    What worked and what didn't

    Compared with controls, problematic short-form video users showed a higher false-alarm rate and lower boundary separation in the go/no-go task. There were no significant group differences in the other DDM parameters. In the contingency degradation task, they showed a stubborn ratio score during action-outcome congruence transitions, and this score correlated positively with the boundary separation index.

    What to keep in mind

    The abstract does not describe limitations in detail. The findings come from a relatively small sample and from the tasks and measures used in this study.

    • Problematic short-form video users showed a higher false-alarm rate than matched controls.
    • They also showed lower boundary separation in the go/no-go task.
    • No significant group differences were found in the other drift-diffusion model parameters.
    • In the contingency degradation task, problematic short-form video users showed a stubborn ratio score during action-outcome congruence transitions.
    • The authors link the inhibitory control deficit to a more impulsive decision-making pattern and insensitivity to task-setting changes.

  • Tolstoy shaped Wittgenstein’s ethical thinking

    What the study found

    The article argues that Leo Tolstoy had an ethical influence on Ludwig Wittgenstein. It presents this influence as especially important in Wittgenstein’s turn toward questions of conscience, guilt, authentic life, and responsibility toward others.

    Why the authors say this matters

    The authors suggest that Tolstoy’s ideas helped shape Wittgenstein’s spiritual and ethical search, especially during the First World War. They also conclude that the comparison helps show how ideas about moral self-discipline, non-resistance to evil, and spiritual purification were taken up by Wittgenstein.

    What the researchers tested

    The article examines Tolstoy’s The Gospel in Brief and compares it with Wittgenstein’s philosophical and ethical views. It traces biographical and intellectual connections between the two thinkers and considers their views on faith, inner rebirth, meaning in life, harmony with the world, and the role of art.

    What worked and what didn't

    The article says Wittgenstein’s engagement with Tolstoy during the First World War was an important stage in his spiritual quest. It also states that Tolstoy’s ideas on non-resistance to evil, self-discipline, and strictness toward oneself shaped Wittgenstein’s ethical and philosophical constructions, despite their different cultural and historical contexts.

    What to keep in mind

    The abstract does not describe experimental limits or empirical testing. Its claims are interpretive and comparative, and the summary available here does not provide detailed evidence beyond the article’s stated analysis.

    • The article claims Tolstoy ethically influenced Wittgenstein.
    • Tolstoy’s The Gospel in Brief is presented as a key source for this influence.
    • Wittgenstein’s First World War period is described as important to his spiritual development.
    • The article links Tolstoy’s ideas to Wittgenstein’s views on conscience, guilt, and authentic life.
    • The comparison also covers meaning in life, harmony with the world, and art as spiritual self-restraint.

  • DENEYAP workshops linked strong techno-philosophy with learner gains

    What the study found

    The study found that the DENEYAP Technology Workshops program was described as successful when leaders’ and instructional teams’ visions aligned and when the program had a strong techno-philosophy, meaning a clear view of how technology should be understood and taught. It also found that the program fostered learners’ interest and competence in techno-scientific thinking skills.

    Why the authors say this matters

    The authors conclude that nonformal learning can play a critical role in preparing the next generation for a technology-driven future. They suggest this happens through technology and design education grounded in a strong and rigorous techno-philosophical and techno-pedagogical design, meaning careful thinking about both the philosophy of technology and how it is taught.

    What the researchers tested

    This was a mixed-methods study of the DENEYAP Technology Workshops program, launched in 2017 by the T3 Foundation for 4th- to 9th-grade students. The researchers interviewed founders and program developers, analyzed lesson plans, and observed classrooms to examine the program’s curriculum and instructional methods.

    What worked and what didn't

    The findings indicate that collaboration with official and unofficial institutions brought important benefits, and that the empathizing stage of the design cycle, meaning the needs-analysis stage, was especially important. The study also identified areas for improvement: ongoing trainer professional development, infrastructure and material provision, and quality assurance in assessment practices, described here as the test stage of the design cycle.

    What to keep in mind

    The summary does not describe numerical outcome measures or comparative tests across different programs. The abstract also does not provide detailed limitations beyond noting areas that need improvement.

    • The program was linked to learners’ interest and competence in techno-scientific thinking skills.
    • Alignment between leaders’ and instructional teams’ visions was associated with success.
    • The empathizing, or needs-analysis, stage in the design cycle was described as crucial.
    • Collaboration with official and unofficial institutions was said to provide important benefits.
    • The abstract notes needs for stronger trainer development, infrastructure, and assessment quality assurance.

  • Blockchain features align with specific supply chain financing frictions

    What the study found

    The study found that blockchain-enabled supply chain financing (BCF) solutions are linked to specific financing frictions, and that these links are not random. Transactional friction was the most prominent, while bankruptcy costs and taxes were rarely associated with blockchain features in the sample.

    Why the authors say this matters

    The authors conclude that understanding how blockchain features align with particular financing frictions may improve the chances of success in supply chain finance. They also suggest that the study provides a way to use AI to evaluate large amounts of unstructured data in operations management research.

    What the researchers tested

    The researchers used a theory elaboration approach to examine which financing frictions BCF solutions aim to address, which blockchain features they use, and how those frictions and features are associated. They analyzed 312 documents describing 11 BCF solutions, including both successful and failed cases, and used AI-based large language models to identify patterns.

    What worked and what didn't

    The analysis identified seven types of financing frictions and three key blockchain features. Transactional friction and hidden actions frictions were linked to all three blockchain features, while other frictions were usually linked to only one. Tokenization was used sparingly and appeared only in successful BCF solutions in this sample.

    What to keep in mind

    The findings come from 11 BCF solutions described in 312 documents, so the scope is limited to that sample. The abstract does not provide further limitations beyond this scope.

    • The study examined 312 documents describing 11 blockchain-enabled supply chain financing solutions.
    • Transaction-related friction was the most prominent friction in the sample.
    • Bankruptcy costs and taxes were rarely associated with blockchain features in the analyzed cases.
    • Tokenization was used sparingly and appeared only in successful BCF solutions.
    • Transactional and hidden actions frictions were linked to all three blockchain features.

  • Arbitrary reference conflicts with weak discernibility

    What the study found

    The author argues that the theory of arbitrary reference is inconsistent with the thesis that weakly discernible entities are metaphysically possible. Weakly discernible entities are described as entities that share all intrinsic and relational properties, yet stand in a symmetric and irreflexive relation.

    Why the authors say this matters

    The study suggests this is important because the thesis that weakly discernible entities are metaphysically possible is presented as plausible and supported by several arguments. The authors conclude that if that thesis is true, then the theory of arbitrary reference is false, and some claimed applications of the theory would also fail.

    What the researchers tested

    The paper examines the theory of arbitrary reference, first proposed by Breckenridge and Magidor in 2012, and compares it with the thesis about weakly discernible entities. The article is a philosophical argument rather than an empirical study.

    What worked and what didn't

    According to the abstract, the argument supports the claim that arbitrary reference cannot be combined with the metaphysical possibility of weakly discernible entities. The abstract also states that two kinds of consequences follow for advocates of arbitrary reference: the theory would be false if the thesis is true, and some proposed applications, including those used by ante rem structuralists, would fail.

    What to keep in mind

    The abstract gives only the author's argument and does not describe counterarguments, tests, or detailed evidence. It also does not provide a full account of all applications of arbitrary reference, only noting that some depend on the disputed thesis.

    • The paper argues that arbitrary reference is inconsistent with the metaphysical possibility of weakly discernible entities.
    • Weakly discernible entities are defined as sharing all intrinsic and relational properties while standing in a symmetric and irreflexive relation.
    • The abstract says the thesis about weakly discernible entities is strikingly plausible and supported by several arguments.
    • The author claims that if that thesis is true, then arbitrary reference is false.
    • The abstract says some applications of arbitrary reference, including for ante rem structuralists, depend on the disputed thesis.

  • Asset shocks spill over differently in liquidity traps

    What the study found

    The study finds that shocks to asset supply or demand can have different international spillovers when an economy is in a liquidity trap, a situation where interest rates are near zero and monetary policy is constrained. In the model, a decrease in assets issued abroad creates an asset shortage at home.

    Why the authors say this matters

    The authors suggest that the supply of bonds matters in this non-Ricardian framework, where households value liquidity and asset scarcity affects outcomes. They conclude that the same shock can have different effects in normal times and in a liquidity trap.

    What the researchers tested

    The researchers built a two-country heterogeneous-agent non-Ricardian model with asset scarcity and financial frictions in international capital markets. They examined how shocks affecting the supply or demand of assets transmit across countries, especially when one economy is in a liquidity trap.

    What worked and what didn't

    In normal times, a decrease in the supply of assets issued abroad lowers the nominal interest rate and stimulates investment and output. In a liquidity trap, the same shock instead leads to deflation, an appreciation of the currency, and may cause a recession.

    What to keep in mind

    The summary provides results from a theoretical model, not from an empirical study. The abstract does not describe empirical data, specific calibration choices, or additional limitations.

    • The study models two countries with asset scarcity and financial frictions in international capital markets.
    • A demand for liquidity emerges because the framework is non-Ricardian, meaning the supply of bonds matters.
    • A fall in assets issued abroad creates an asset shortage at home.
    • In normal times, that shock lowers nominal interest rates and supports investment and output.
    • In a liquidity trap, the same shock leads to deflation, currency appreciation, and may cause a recession.

  • European residents trust professionals most for health app advice

    What the study found

    In this multilingual survey of European residents, most respondents reported using one or more health apps. The most trusted recommendation sources were health professionals, pharmacists, and government or health authorities, but family and friends were used more often than professional sources.

    Why the authors say this matters

    The authors conclude that there is public support for government-led review and rating schemes to guide consumer choice. They also suggest that making trustworthy, easy-to-find information available at the point of download, and supporting health care professionals in recommending high-quality apps, could help bridge the gap between trusted and used sources.

    What the researchers tested

    The researchers ran a cross-sectional online survey from December 7, 2022, to February 16, 2023, in 26 languages. It targeted residents of the European Economic Area, the United Kingdom, and Ukraine and asked about app use, sources of advice used and trusted, and views on government review and rating.

    What worked and what didn't

    Among 1228 fully completed responses from 33 countries, 1110 respondents reported using at least one health app. COVID-19 apps and activity apps were most commonly used, while disease management, diagnostic, and treatment apps were least used. Health professionals were the most trusted source, and 86.3% of respondents supported government review and rating of health apps.

    What to keep in mind

    The survey included only fully completed responses, so the findings reflect that sample rather than all residents in the region. The abstract does not provide details on response rate, and the subgroup findings are limited to the specific trust comparisons reported.

    • Most respondents reported using one or more health apps.
    • Health professionals were the most trusted source of app recommendations.
    • Family and friends were used more often than professional sources when choosing apps.
    • 86.3% of respondents supported government review and rating of health apps.
    • COVID-19 apps and activity apps were the most commonly used app types.

  • Automation reduces rents and wage dispersion in exposed workers

    What the study found

    The study finds that automation in a task-based economy tends to target high-rent tasks, meaning tasks that pay wages above workers' outside options. The authors report that this dissipates rents, amplifies wage losses, and reduces within-group wage dispersion among exposed groups.

    Why the authors say this matters

    The authors conclude that this form of rent dissipation is inefficient and offsets the productivity gains from automation. They also say the findings help explain wage inequality patterns, including between-group inequality and wage dispersion within groups.

    What the researchers tested

    The researchers studied automation in a task-based economy where some jobs pay rent, meaning wages above workers' outside options. They used U.S. data from 1980 to 2016 to examine how automation relates to wages, inequality, productivity, and rent dissipation.

    What worked and what didn't

    The authors find evidence of sizable rent dissipation and reduced within-group wage dispersion due to automation. They estimate that automation accounts for 52% of the increase in between-group inequality since 1980, with rent dissipation explaining one-fifth of this total. They also estimate that inefficient rent dissipation offset 60% to 90% of the productivity gains from automation over the period studied.

    What to keep in mind

    The abstract describes findings for the U.S. from 1980 to 2016, so the results are limited to that setting and time period. The abstract does not describe additional limitations beyond the study's focus on a task-based economy and the measured relationships in the available data.

    • Automation in the model targets high-rent tasks, not just tasks in general.
    • Rent dissipation is described as inefficient and as offsetting productivity gains.
    • Using U.S. data from 1980 to 2016, the authors find evidence of sizable rent dissipation.
    • Automation accounts for 52% of the rise in between-group inequality since 1980.
    • Rent dissipation explains one-fifth of that inequality increase.
    • The authors estimate that 60% to 90% of automation's productivity gains were offset.