A team of Chinese and international researchers has created the world's first spatially resolved map of the spectral index of a black hole at the scale of its event horizon, opening new possibilities for studying the extreme physical environment around these objects.
The study, published in The Astrophysical Journal Letters on Monday, was conducted by scientists from the Shanghai Astronomical Observatory of the Chinese Academy of Sciences in collaboration with international partners. The team analyzed data obtained in 2018 using the Event Horizon Telescope (EHT) and the Global Millimeter VLBI array, studying the supermassive black hole M87.
By combining images taken at wavelengths of 1.3 millimeters and 3.5 millimeters, the researchers performed the first two-frequency spectral analysis at the event horizon scale. The resulting map of the black hole's spectral index allows for a description of how the radiation brightness changes at different frequencies, which scientists compared to a high-precision 'health check' of the black hole.
The results obtained demonstrate significant changes in the properties of radiation around the black hole depending on the distance from its center. Near the event horizon, the spectral index is positive, indicating a strong influence of synchrotron self-absorption on the radiation. However, further from the center, the spectral index gradually decreases and becomes negative, suggesting a transition of the radiation into an optically thin state.
This transition occurs at approximately 30 microarcseconds from the center of the black hole, corresponding to the size of the ring structure observed at the 3.5 millimeter wavelength. This discovery suggests that this ring is not only a visible feature of the black hole image but also reflects the state of the plasma near the event horizon.
The researchers note that future observations at additional frequencies will allow for more precise measurements of the plasma conditions around black holes. This will help track the evolution of accretion flows and jets over time, advancing the study of black holes from static imaging to dynamic physical diagnostics.
Artificial intelligence is beginning to generate financial results for tech giants; however, the accelerated increase in investments is exerting strong pressure on the financial health of these corporations.
According to Reuters, the financial market awaits the next earnings reports to verify whether the increase in revenue will be able to keep pace with the high costs of technological infrastructure. The so-called hyperscalers—which include Microsoft, Alphabet, Amazon, Meta, and Oracle—continue to significantly increase their investments in AI.
Projections indicate that by 2027, spending growth is expected to surpass free cash flow generation. A survey conducted by Reuters, using estimates from LSEG, points out that these companies are expected to increase their annual operating cash flow by US$ 340 billion (equivalent to approximately R$ 1.72 trillion) between 2025 and 2027. Conversely, planned investments for the same period are expected to grow by about US$ 534 billion (approximately R$ 2.71 trillion), representing an investment of US$ 1.57 for every US$ 1 generated in cash.
Although cost challenges are evident, signs of positive returns have already emerged. Microsoft reported that its AI division achieved annual revenue exceeding US$ 37 billion (about R$ 187.6 billion). Amazon's AWS demonstrated 28% growth during the first quarter.
Shay Boloor, Chief Market Strategist at Futurum Equities, commented that investors are minimizing the transformative impact of AI on the business model of Big Tech. He emphasized that sectors such as software, advertising, and cloud computing have increasingly become dependent on large investments in physical infrastructure. This movement includes building new data centers, acquiring servers and network equipment, expanding cloud infrastructure, and increasing demand for artificial intelligence solutions.
Regarding Microsoft, the company recorded US$ 35.8 billion (about R$ 181.5 billion) in operating cash flow in the second fiscal quarter, while its investment expenditures totaled US$ 37.5 billion (approximately R$ 190.1 billion). There is a concern that the increase in profits may not be sufficient to justify the investments if capital expenditures are draining cash, given that the primary goal of the companies is to generate profit.
David Russell, Global Head of Market Strategy at TradeStation, commented to Reuters on the scenario. Among the five analyzed companies, Oracle generates the most apprehension. Its shares have fallen by 36% over the year, its free cash flow showed a negative result, and the company plans to raise between US$ 45 billion and US$ 50 billion (equivalent to R$ 228.2 billion to R$ 253.5 billion) to expand its cloud infrastructure. Upcoming financial statements will be crucial in determining whether AI progress can keep pace with this level of expenditure.
Enterprises continue to underestimate the security threats inherent in modern voice networks. Many view voice services merely as ordinary phone calls, ignoring the fact that they are complex IP systems susceptible to the same threats as the company's other digital infrastructure.
According to Peter Bokaba, Network Manager at Centracom, the main danger lies in how easily corporate voice systems can be compromised without basic protection. Bokaba explains that when Voice over IP or PBX devices are hacked, attackers can generate fraudulent calls to expensive international destinations that they control or profit from through revenue-sharing schemes.
He warns that a company that usually pays a monthly bill of R10,000 could suddenly face expenses ten or twenty times higher if the systems are accessed without proper control.
Scammers often use automated scripting tools for multiple login attempts or to exploit open systems on a large scale. After gaining access, they can redirect calls through premium or high-cost international destinations, which quickly increases the costs for the affected organization.
Bokaba notes that while some risks are related to basic vulnerabilities, such as weak credentials or unsecured systems, modern voice infrastructure requires a multi-layered approach to security. On a practical level, enterprises must perform simple but critical tasks, such as regularly updating credentials.
Furthermore, additional controls must be implemented, including encrypted tunnels, IP-based authentication, and network segmentation, so that voice systems are not directly accessible from the public internet. Centracom also emphasizes the importance of proactive monitoring and threshold-based controls that can signal or limit unusual call behavior before significant losses occur. Bokaba adds that it is important to educate companies about what voice fraud is, as many organizations still consider voice a simple service rather than part of their digital attack surface.
Bokaba concludes that the current focus should be on raising awareness of these risks while simultaneously implementing proven protective measures to reduce vulnerability to fraud and unauthorized use. The company asserts that voice security should be viewed not as a niche or emerging discipline, but as a fundamental part of network management, requiring the same operational discipline as any other critical IT system. The ultimate goal, according to Bokaba, is to ensure that what appears to be an ordinary phone call is actually protected as part of a much more complex and valuable network environment.
Researchers discovered that individuals who demonstrate faith in science can also adopt scientific-nature conspiracy theories, such as unfounded skepticism about vaccines or unproven claims regarding environmental phenomena.
An analysis conducted with 843 residents of the United States, and published in the journal Current Psychology, suggests that the way people conceive of scientific progress and the channels through which they obtain information exerts greater influence on these convictions than factors such as educational level.
The survey indicated that perceiving science as the product of isolated geniuses, coupled with frequent consumption of media such as podcasts and documentaries, is linked to a greater predisposition to accept conspiratorial explanations presented with a scientific veneer.
The study, conducted by Michele d’Errico and Taha Yasseri, sought to understand how the appreciation of science can coexist with the acceptance of claims that contradict the scientific method itself. The investigation stemmed from a globally observed contradiction: despite science being viewed as a highly reliable institution by the majority, false information continues to circulate with great force.
The authors argue that the core of the issue lies not only in the degree of trust placed in scientists but also in the public's understanding of how scientific knowledge is generated. For them, some members of the public associate science with external indicators of authority, such as technical terminology, advanced equipment, exact numbers, and academic titles, without necessarily grasping the procedures used to validate discoveries.
The research established a connection between two characteristics: the so-called 'genius mentality,' which attributes major advances to exceptional individuals who challenge the consensus, and the preference for non-formal scientific dissemination sources, such as documentaries and podcasts. Participants with higher scores in these criteria showed a greater inclination to agree with conspiracy theories.
The results observed by the researchers were more significant than variables traditionally linked to such beliefs, such as political stance or education. The survey also revealed that the influence of the notion of the 'lone genius' was more prominent among individuals with low or moderate trust in scientists, while this difference was minimal among those who already had high trust in the scientific community.
According to the researchers, popular representations of science often reinforce a narrative where major discoveries emerge from the actions of a single extraordinary person. Films, biographies, and documentaries tend to portray scientists as figures who face initial resistance, remain firm in their ideas, and are recognized later.
This construction ignores the collective mechanisms that sustain science, such as peer review, experiment replication, debates, and constant revisions. Valid scientific knowledge does not depend solely on a brilliant idea, but rather on shared verification processes.
The authors warn that conspiracy theories can exploit this image of the misunderstood individual to construct a narrative of intellectual superiority. In this context, whoever adopts an alternative explanation begins to see themselves as someone capable of discerning a truth that others ignore.
One case cited in the study involves the Italian chemist Corrado Malanga and the radar researcher Filippo Biondi. In March 2025, both claimed to have located an underground structure beneath the Pyramid of Khafre in Egypt using satellite radar images. Archaeologists refuted this claim, pointing to the technical limitations of this method for detecting structures at considerable depths.
Despite the criticism, Biondi presented his hypothesis in January 2026 on the podcast The Joe Rogan Experience, reaching a vast audience. This episode serves, according to the authors, as an illustration of how content with a scientific appearance can gain visibility even when experts question its foundations.
Another aspect emphasized by the researchers is the role of communication platforms and formats. An analysis of 8.7 million publications on the former Twitter platform, now known as X, examined the sharing of considered verified content and found that mentions of scientific elements, such as universities, studies, or scientists, increased the dissemination of these messages.
This effect was particularly noticeable in content classified as low credibility and among users with a more right-leaning political inclination. Thus, the presence of scientific elements can function as a credibility indicator, even when the conveyed information does not meet scientific criteria.
The authors suggest that strategies focused only on correcting incorrect facts may not solve the problem. It is essential to explain more clearly how science builds knowledge and why divergences, revisions, and joint evaluations are part of the process. The suggestion is to empower citizens to understand the origin of scientific information, even without being specialists, allowing them to better assess the quality of evidence and distinguish scientific consensus from mere assertions that use scientific language.
The researchers advise that science teaching should not be limited to presenting ready-made conclusions and theories. It is also recommended to demonstrate the daily functioning of the scientific community, including collaboration, contestation, and shared criteria. Understanding that scientific consensus is built after rigorous analyses helps prevent the interpretation that agreement among experts implies a lack of critical thinking. The ultimate purpose of this study is to decrease susceptibility to future conspiracy theories before they become generalized, strengthening public understanding of the methods that confer reliability to science.
