
Month: September 2025
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Holograms
Optoelectronics research could bring holograms to your smartphone and closer to everyday use
Holograms: Researchers at the University of St Andrews have developed a novel optoelectronic device combining holographic metasurfaces (HMs) with organic light-emitting diodes (OLEDs), opening new possibilities for holographic technology in smart devices, communication, gaming, and entertainment, as reported in Light: Science & Applications.
What is a hologram?
A hologram is a three-dimensional image created by recording and reconstructing the light wavefront from an object. Unlike traditional photos, which capture only intensity, holograms preserve both amplitude and phase, allowing viewers to see depth, parallax, and multiple perspectives. There are two main types:
- Optical holograms: Created using lasers and physical objects.
- Computer-generated holograms: Simulated digitally and displayed via specialised hardware.
How is it formed?
- Traditional Method (Laser-based): A laser beam is split into two parts: the object beam (reflected from the object) and the reference beam (directed onto the recording medium). When these beams meet on a recording plate, they create an interference pattern. On illumination, this pattern reconstructs a 3D image of the original object.
- New Research Breakthrough (St Andrews, 2025): Uses OLEDs (Organic Light-Emitting Diodes) + Holographic Metasurfaces (HMs). Each meta-atom of the HM modifies light at the pixel level, shaping it to create interference patterns. This eliminates bulky laser setups, making hologram generation cheaper, compact, and scalable.
Where is a hologram used?
Holograms are already embedded in many aspects of daily life:
- Security: On credit cards, passports, and currency to prevent counterfeiting.
- Entertainment: Concerts (e.g., Tupac’s holographic performance), theme parks, and AR/VR experiences.
- Education: Interactive anatomy lessons, historical reconstructions, and immersive learning.
- Medical Imaging: 3D visualisation of organs and surgical planning.
- Telecommunications: Holographic video calls and remote presence.
- Retail & Advertising: 3D product displays and interactive marketing.
What are its potential applications?
- Consumer Electronics → next-gen holographic smartphones, tablets, and TVs.
- Virtual & Augmented Reality (VR/AR) → lightweight, compact holographic displays for immersive experiences.
- Gaming & Entertainment → interactive 3D projections without bulky equipment.
- Communication → real-time holographic telepresence (3D video calls).
- Medical Imaging → holographic visualisation for diagnostics and surgery.
- Biophotonics & Sensing → miniaturised, light-based platforms for advanced sensing.
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Earthworms and Regenerative Vineyards
Context: Earthworms, often overlooked and underappreciated, are vital to soil health, biodiversity, and sustainable agriculture. As their populations decline due to modern farming practices and environmental stressors, winemakers and farmers are being urged to adopt regenerative methods to “wake” these silent soil engineers—before it’s too late.
What are earthworms?
Earthworms are terrestrial invertebrates belonging to the phylum Annelida. They have segmented, tube-like bodies and live in soil, where they feed on organic matter such as decaying leaves, microbes, and detritus. They breathe through their skin and possess both male and female reproductive organs (hermaphrodites), playing a crucial role in decomposition and nutrient cycling.

Where are they generally found?
- Earthworms thrive in moist, nutrient-rich soils across the globe. They are commonly found:
- In gardens, forests, and agricultural fields
- Beneath leaf litter, compost piles, and mulched areas
- Along riverbanks, under rocks, and in tree bark
- In temperate and tropical climates, avoiding dry or overly wet soils
- They burrow deeper during winter or droughts and surface during rain, making them sensitive indicators of soil health.
What are the recent events that are declining earthworms?
- Earthworm populations are declining globally, with some regions reporting a 33–41% decrease over the past 25 years. Key drivers include:
- Chemical Use: Pesticides and synthetic fertilisers disrupt soil biology and poison earthworms.
- Soil Compaction: Heavy machinery crushes burrows and reduces oxygen levels.
- Habitat Loss: Urban expansion and deforestation reduce suitable habitats.
- Extreme Weather: Heavy rains and droughts force worms to surface or burrow deep, increasing mortality.
- Climate Change: Warmer, drier summers reduce soil moisture, especially in woodlands.
- This decline threatens soil fertility, food chains, and carbon sequestration, with ripple effects across ecosystems.
How can regenerative farming help?
Regenerative farming restores soil health by working with nature, not against it. For earthworms, this means:
- Farming Practices That Support Earthworms:
- No-till or low-till farming: Preserves worm tunnels and microbial networks.
- Cover cropping provides organic matter and shade, thereby improving moisture retention.
- Composting & mulching: Feeds earthworms and boosts microbial life.
- Organic inputs: Avoids harmful chemicals, fostering biodiversity.
- Rotational grazing: Prevents over-compaction and enhances nutrient cycling.
- Vermicomposting: Uses earthworms to convert farm waste into vermicast, a potent organic fertiliser. Reduces landfill waste and chemical dependency while enriching soil naturally.
- Ecosystem Restoration: Earthworms help rebuild degraded soils, restore pH balance, and increase carbon storage. Their activity supports plant immunity, disease resistance, and water retention.
- Earthworms thrive in moist, nutrient-rich soils across the globe. They are commonly found:
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Atlantic Meridional Overturning Circulation (AMOC)
Collapse of critical Atlantic current is no longer low-likelihood, study finds
Context: Recent studies warn that the Atlantic Meridional Overturning Circulation (AMOC) may be closer to a tipping point than previously believed. New model runs suggest collapse could become inevitable within the next few decades, even under low-emission scenarios, highlighting the urgency of cutting fossil fuel emissions.

What is an AMOC?
- AMOC stands for Atlantic Meridional Overturning Circulation. It’s a massive system of ocean currents that acts like a conveyor belt, moving warm, salty water from the tropics northward to the North Atlantic. There, the water cools, becomes denser, sinks, and flows back southward at deeper levels.
- This cycle is driven by differences in water temperature and salinity—a process called thermohaline circulation. It’s slow but powerful, taking about 1,000 years for a parcel of water to complete the full loop.
What is the significance of AMOC?
AMOC plays a critical role in regulating global climate and ocean health:
- Climate Stabilisation: Keeps Western Europe warmer than other regions at similar latitudes (e.g., Canada). Influences monsoon systems in South Asia, West Africa, and the Amazon.
- Ecosystem Support: Circulates nutrients and oxygen, supporting marine biodiversity and fisheries.
- Carbon Sink Function: Absorbs and stores atmospheric CO₂, helping mitigate global warming.
- Weather Patterns: Affects rainfall distribution, hurricane activity, and sea ice formation.
Without AMOC, many regions would experience extreme climate shifts, including colder winters in Europe, rising sea levels along the U.S. East Coast, and droughts in the Sahel and South Asia.
How does climate change influence AMOC?
Climate change is weakening AMOC, and could eventually cause its collapse:
- Melting Ice & Freshwater Influx: Greenland’s melting ice adds freshwater to the North Atlantic, reducing salinity and density. This disrupts the sinking of cold water, a key driver of AMOC.
- Ocean Warming: Warmer surface waters are less dense, making it harder for them to sink and complete the circulation loop.
- Increased Rainfall: More precipitation dilutes ocean salinity, further weakening the thermohaline engine.
- Model Predictions: Studies show AMOC is at its weakest in over 1,600 years. Under current emissions trajectories, there’s a 25–70% chance of collapse by 2100, depending on the scenario.
A collapse would trigger irreversible climate shifts, including: Severe cooling in Europe, Disruption of tropical rain belts, Accelerated sea level rise, and Altered marine ecosystems.
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India as an ‘Oil Money Laundromat’
Context: The recent comments by former White House trade adviser Peter Navarro, labelling India an “oil money laundromat,” exemplify the growing tension between strategic partnerships and the enforcement of a Western-led geoeconomic order.

What are laundromat countries?
- In the context of international sanctions and energy trade, a “laundromat country” is a pejorative term used to describe a nation that acts as a financial and logistical intermediary to circumvent economic sanctions.
- Specifically for Russian oil, it refers to a country that:
- Purchases crude oil from a sanctioned nation (like Russia) at a significant discount.
- Refines this oil domestically into petroleum products such as diesel, gasoline, or jet fuel.
- Sells these refined products at market price to other countries, including those that have imposed the original sanctions on the oil source.
- This process “launders” the origin of the oil, obscuring its source and allowing the sanctioned country to continue earning vital foreign currency (like US dollars or Euros) through indirect means.
- While the practice may not violate the letter of international law or specific sanctions (especially if the oil is significantly transformed), it is criticised for violating the spirit of the sanctions and providing an economic lifeline to the targeted regime.
Why are laundromat countries concerned about the geoeconomic order?
- Sovereignty and Strategic Autonomy: They view the expectation to adhere to sanctions they did not agree to as an infringement on their national sovereignty and right to make independent foreign policy choices based on their own strategic and economic interests.
- Economic Stability and Development: For developing economies like India, access to cheap energy is a non-negotiable prerequisite for rapid industrialisation, economic growth, and poverty alleviation.
- They are concerned that being forced to abandon the cheapest available source of energy would hamper their development trajectory and increase inflation for their citizens.
- Hypocrisy and Double Standards: These countries often point to Europe’s continued (though now reduced) purchases of Russian natural gas via pipelines or the historical lack of enforcement of similar sanctions on other global actors as evidence of a selective and hypocritical application of rules.
- Fear of Secondary Sanctions: Their primary practical concern is the potential imposition of secondary sanctions by the U.S.
- These are sanctions that could target their own companies, banks, and financial institutions for doing business with Russia, cutting them off from the dollar-dominated global financial system (e.g., being excluded from SWIFT).
- This threat represents a direct tool of enforcement that could force compliance with the Western-led order, regardless of their objections.
- Reshaping Global Governance: There is a longer-term concern among emerging powers about being forced to choose sides in a new Cold War.
- They prefer a multipolar world where they can maintain relationships with multiple blocs (the U.S., Russia, China) rather than a bipolar order where Western alliances constrain their economic choices.
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Unstable World and Energy Sovereignty
Context: India’s energy landscape is defined by a critical vulnerability: over 85% of its crude oil and 50% of its natural gas are imported, constituting a quarter of its total import bill and posing a significant national security risk.
More on News
- Historically, global energy security has been reshaped by shocks—from the 1973 oil embargo to the 2022 Russia-Ukraine war—each teaching that sovereignty is impossible without diversification and resilience.
- Despite the global push for transition, fossil fuels still dominate, creating a structurally tight market.

What is energy security?
- Energy security is the uninterrupted availability of energy sources at an affordable price. For a nation, it means ensuring that its citizens, industries, and military have reliable access to the energy needed for economic stability and national security without being subject to disruptive shocks or geopolitical coercion.
- In the modern context, energy security also includes the stability of the entire energy system, from generation and import infrastructure to transmission grids and storage capabilities, ensuring resilience against physical, cyber, and geopolitical threats.
What are the major challenges to India’s energy security?
- High Import Dependence: The foremost challenge is India’s heavy reliance on imported fossil fuels (oil and gas), which exposes the economy to volatile global prices and supply disruptions, strains foreign exchange reserves, and widens the trade deficit.
- Geopolitical Volatility: A significant portion of India’s imports traditionally transited through volatile regions like the Strait of Hormuz.
- Concentrated Supply Sources: While diversification has improved, over-reliance on any single partner (e.g., Russia for crude) creates new vulnerabilities to geopolitical shifts or potential secondary sanctions.
- Inadequate Domestic Production: Stagnant domestic production of oil and gas fails to keep pace with rapidly growing demand, perpetuating import dependence.
- Financing the Energy Transition: The enormous capital required to develop domestic alternatives like renewables, nuclear, green hydrogen, and storage infrastructure is a significant hurdle.
- Grid Resilience and Integration: As the share of intermittent renewable energy (solar, wind) grows, managing grid stability, ensuring adequate storage (like pumped hydro), and maintaining a dispatchable power base (like nuclear or gas) become critical technical challenges.
- Global Climate Pressures: International pressure to decarbonise necessitates a careful and costly balancing act between using domestic fossil resources (like coal), ensuring affordable energy, and investing in a green transition.
What measures have been taken to address India’s energy security?
- Diversification of Energy Sources:
- Russian Oil: Capitalised on discounted Russian crude to reduce costs and diversify away from traditional West Asian suppliers.
- Strategic Petroleum Reserves (SPRs): Built underground reserves in Vishakhapatnam, Mangaluru, and Padur to buffer against supply disruptions for approximately 9.5 days.
- Ethanol Blending Programme: Mandated blending ethanol with petrol, aiming for E20 (20% ethanol) by 2025-26.
- Promotion of Domestic Alternatives:
- SATAT Scheme: Promotes the establishment of Compressed Biogas (CBG) plants to produce biogas from agricultural waste, providing clean fuel and organic manure.
- Coal Gasification: Initiatives to leverage India’s vast coal reserves through gasification to produce syngas, methanol, and hydrogen, reducing import dependency.
- Renewable Energy Push: Ambitious targets of 500 GW of non-fossil fuel capacity by 2030, focusing on solar and wind power.
- Building Future Resilience:
- Green Hydrogen Mission: A National Mission aims to make India a global hub for the production and export of Green Hydrogen, targeting 5 MMT per annum by 2030.
- Nuclear Energy: Efforts to revive the nuclear sector, including the thorium program and exploring Small Modular Reactors (SMRs) for dispatchable, zero-carbon power.
- Pumped Storage Projects (PSPs): Policy push to develop PSPs, which are crucial for grid balancing and storing renewable energy.
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SCO Summit and India-China Relations
Context: Prime Minister Narendra Modi is attending the Shanghai Cooperation Organisation (SCO) summit in Tianjin, marking his first visit to China since 2018.
What is the SCO?
- The Shanghai Cooperation Organisation (SCO) is a permanent intergovernmental international organisation formed in 2001 in Shanghai by China, Russia, Kazakhstan, Kyrgyzstan, Tajikistan, and Uzbekistan.
- It expanded to include India and Pakistan in 2017, Iran in 2023, and Belarus in 2024, now comprising ten member states.
- The SCO covers 24% of the world’s land area and 42% of its population, making it the world’s largest regional group by both geography and population.
- Its objectives include fostering mutual confidence, deepening political, economic, and security cooperation, and promoting stability in the Eurasian region.
- The SCO operates on the principles of mutual trust, respect for sovereignty, non-alignment, and open partnerships.
What is the significance of SCO?
- It is the only major regional platform bringing together key Central and South Asian nations, and pivotal powers like China, Russia, and India under a single framework.
- Its focus on countering terrorism, separatism, and extremism is operationalised through permanent institutions like the Regional Anti-Terrorist Structure (RATS), which coordinates anti-terror efforts among members.
- It is a strategic counterbalance to Western-dominated institutions, offering its members alternative modes of cooperation and multilateral engagement.
- Through shared economic initiatives, connectivity projects, and regional security cooperation, the SCO aims to promote peace, economic growth, and stability across Eurasia, particularly as it expands to include resource-rich and geographically pivotal countries like Iran and Belarus.
Why is the current SCO Summit essential?
- It marks a potential reset in India-China ties amidst global flux and recent bilateral thaw, offering scope for dialogue on key issues such as border management, economic partnerships, and resumption of direct people-to-people links like flights and pilgrimages.
- The summit occurs at a time when India is reassessing its strategic autonomy, balancing relations with Russia, the US, and China, especially as trade frictions with the US mount.
- Leaders from 20 countries, including member and observer states, make this the largest-ever SCO summit, underlining the group’s expanding geopolitical reach and importance in global governance.
Key strategic decisions, such as the next ten-year development plan and cooperation on counter-terrorism and economic integration, are on the agenda, shaping the region’s response to new global and regional security, economic, and diplomatic challenges.
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Cashless Bail in India: A Transformative Lesson for Justice Reform
Cashless Bail in India: A Powerful Step Toward Fair Justice
Context: Donald Trump’s tariff escalations are highly relevant today as global trade tensions intensify, with the U.S. adopting aggressive protectionist measures. These policies not only reshape U.S.–China economic rivalry but also impact global supply chains, inflation, and India’s trade and diplomatic strategies in a shifting world order.
What is a cashless bail?
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How is it different from the bail system in India?
India’s bail process is governed by the Bhartiya Nagarik Suraksha Sanhita, 2023 (replacing the Code of Criminal Procedure, 1973). Bail conditions generally involve:
- Bond: Accused signs an undertaking and often deposits cash, forfeitable if terms are violated.
- Bail Bond: A surety (family/friends/employer) provides financial backing. In Mumbai, a solvency certificate from revenue authorities is required.
- Personal Recognisance (PR) Bond: In theory, allows release without immediate cash, but courts rarely grant it.
Unlike US reforms, Indian bail remains heavily financially contingent. The result is a two-tiered justice system—wealthier accused secure release easily, while poorer undertrials languish in jail.
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- Cashless bail, also known as non-monetary bail or bail reform, refers to releasing an accused without demanding a cash deposit. Instead of ability to pay, the court assesses flight risk, threat to society, and likelihood of appearing for trial.
- This system emerged in the US after glaring inequities of the money-bail system.
- A notable case is Kalief Browder (2010–2015), a teenager who spent three years in jail, including over 700 days in solitary confinement, because his family could not pay a $3,000 bail. His eventual suicide became a catalyst for bail reform.
- Several US jurisdictions like Washington D.C. (since 1992), New Jersey (2017), and Illinois (2023) have abolished cash bail, relying instead on judicial risk assessments.
- Research by the Brennan Center for Justice found no significant correlation between bail reform and increase in crime rates, countering political fears.
Why is there a need for a change in the bail system in India?
- India faces a chronic problem of undertrial prisoners. As per the National Crime Records Bureau (NCRB) 2021, nearly 77% of India’s prison population are undertrials. Many remain in custody for inability to pay even small bail amounts (sometimes as low as ₹5,000).
- The Law Commission’s 268th Report (2017) termed monetary surety “contrary to constitutional ethos” and violative of the right to equality. The Supreme Court (2023, Kaul & Oka Bench) directed that if bail is granted but not executed within a week due to financial inability, prison authorities must inform the District Legal Services Authority (DLSA) to provide assistance.
- This highlights the urgent need for India to shift towards risk-based assessment models, ensuring liberty is not hostage to wealth.
- The Economic Survey 2018–19 also underlined that judicial reforms, including bail reform, are central to improving India’s Ease of Doing Business and social justice outcomes.
Why is cashless bail controversial in the US but relevant for India?
- In the US, critics argue that cashless bail enables repeat offenders to be released quickly. Former President Trump has linked it to rising crime, though studies (e.g., Brennan Centre, Loyola University Chicago) show little evidence.
- For India, however, the issue is less about crime control and more about equity and constitutional morality. With overcrowded prisons (occupancy rate 118% in 2021, NCRB) and high economic disparity, reforms similar to cashless bail could reduce undertrial incarceration, uphold Article 21 (Right to Life and Liberty), and bring justice closer to its true meaning.