Low-Frequency Gravitational Waves

Why in news?

• Scientists have recently announced a groundbreaking discovery that provides evidence of the existence of low-frequency gravitational waves in the universe.

Detection of Low-Frequency Gravitational Waves

• To detect these elusive low-frequency gravitational waves, scientists employed a different approach compared to previous detections of high-frequency waves.
• The international collaboration involved radio astronomers from five different teams, including the Indian Pulsar Timing Array (InPTA).
• The researchers utilized six large radio telescopes, including one in Pune, to study pulsars, which are rapidly-rotating neutron stars emitting pulses of radiation observed as bright flashes of light from Earth.
• By analyzing the signals from 25 pulsars over 15 years, scientists observed discrepancies in the arrival times of these signals, indicating deformities in spacetime caused by gravitational waves.

The Technology and Study Methodology

• The study team employed advanced technology, including large radio telescopes, to track the precise intervals at which pulsar signals reached Earth.
• The researchers meticulously analyzed the arrival times of these signals and compared them with predicted values.
• They found slight variations, with some signals arriving earlier or later than expected by millionths of seconds.
• These inconsistencies were attributed to the presence of gravitational waves distorting spacetime.

Significance of the Discovery

• The discovery of low-frequency gravitational waves is of great importance to the scientific community.
• It provides valuable insights into the nature and evolution of the universe.
• The detection of a cosmic background “hum” suggests a pervasive presence of gravitational waves throughout the universe.
• This breakthrough expands our understanding of the environment surrounding massive black holes and offers new avenues for studying these phenomena.

Understanding Gravitational Waves

• Gravitational waves are disturbances in the fabric of spacetime caused by the movement, collision, and merging of massive objects.
• According to Newton’s theory of gravitation, the force between two objects is directly proportional to their masses and inversely proportional to the square of the distance between them.
• However, Einstein’s General Theory of Relativity revolutionized our understanding by proposing that gravitational attraction arises from the bending of spacetime caused by massive objects.
• This bending creates ripples, known as gravitational waves, which propagate through the universe.

Evolution from Newton’s Law to Einstein’s General Theory of Relativity

• Newton’s law of gravitation provided accurate descriptions of celestial motion for centuries. However, it had limitations.
• It couldn’t explain why objects were attracted to each other or account for the finite speed of gravitational force propagation.
• Einstein’s General Theory of Relativity, developed in 1915, addressed these deficiencies by introducing the concept of spacetime.
• According to this theory, the curvature of spacetime caused by massive objects produces gravitational attraction. Moving objects create ripples in spacetime, leading to the phenomenon of gravitational waves.

Spacetime

• The Concept of Space and Time: Einstein’s Special Theory of Relativity proposed that space and time are not independent entities but rather intertwined in a four-dimensional continuum called spacetime.
• This concept challenges our everyday perception of space and time as separate entities.
• In spacetime, the motion of objects affects both space and time, creating a unified framework.
• In his later General Theory of Relativity, Einstein further developed the notion of spacetime by describing it as a flexible and dynamic entity that interacts with matter and influences events occurring within it.
• The deformation of spacetime caused by massive objects generates gravitational waves, allowing us to gain insights into the workings of the universe.

GS PAPER – III

Intensified Infrastructure Development in Eastern Ladakh

Why in news?

• Three years after the violent clash between Indian and Chinese forces in Galwan, activity in the eastern Ladakh region remains intense.

Background

• Both sides have initiated several infrastructure projects that have permanently altered the status quo on the ground.
• China is rushing to complete a bridge across the Pangong Tso, while India is constructing a blacktopped road on the north bank of the lake.

Ongoing Dispute and Friction Points

• Despite ongoing construction activities, the two sides continue to face a deadlock in the Corps Commander-level talks.
• Two remaining friction points at Depsang and Demchok involve Chinese blocking of Indian patrols.
• Some progress has been made during the talks, with a partial climb-down observed on the Chinese side.

Indian Infrastructure Development

• India is focused on infrastructure development, including road networks, advanced landing grounds, and blacktopped roads.
• Construction of a blacktopped road towards Finger 4 is underway and expected to be completed by 2025.
• Work on an alternative axis to the critical Darbuk-Skyok-Daulat Beg Oldie road through the Saser La is at an advanced stage.

Chinese Infrastructure Development

• China is constructing a main bridge across the Pangong Tso, with the secondary bridge already completed.
• Significant construction activity is observed on the north bank, including road connectivity towards Shandong village.
• A Chinese air defense site is located east of the Khurnak fort, and a 22-km tunnel is being built along the G-0177 expressway at Yuli, connecting to the G-216 highway in Tibet.

Increased Budgetary Allocation

• The Border Roads Organisation’s budget has significantly increased, reflecting the priority given to infrastructure development.
• In 2023-24, the capital budget for BRO was ₹5,000 crore, a 43% increase from the previous year.
• The India-China Border Roads plan has received a significant portion of the allocated funds, leading to notable progress in the construction of strategic roads along the Line of Actual Control (LAC).

Future Outlook

• The BRO is close to completing key infrastructure projects in the eastern sector, improving all-weather connectivity along the LAC. The intensified infrastructure development aims to strengthen India’s presence and enhance mobility in the region. The completion of these projects will have implications for the ongoing dispute and shape the dynamics between India and China in the area.

GS PAPER – III

Latin America’s Crypto Economy and El Salvador’s Bitcoin Adoption

Why in news?

• The International Monetary Fund (IMF) expressed concerns about fiscal risks and consumer protection issues associated with El Salvador’s move. Recently, Latin American countries like Argentina, Chile, and Colombia have experienced currency devaluation, prompting residents to explore alternative options.

Background

• Some individuals have turned to stablecoins, which are cryptocurrencies designed to reflect the value of fiat currencies.
• Chainalysis’ Global Crypto Adoption Index ranks Brazil, Argentina, Colombia, and Ecuador among the top 20 countries in terms of crypto adoption.
• Central banks in the region are also considering the development of central bank digital currencies (CBDCs), expanding the reach of blockchain-based infrastructure.

El Salvador’s Unique Approach

• El Salvador stands out as the first country to adopt Bitcoin as legal tender.
• President Nayib Bukele has been a vocal supporter of cryptocurrencies and has personally invested in Bitcoin.
• The country uses a digital wallet called Chivo to regulate crypto transactions, but there have been complaints regarding its functionality and security.
• Despite ambitious plans such as issuing Bitcoin bonds and building a “Bitcoin City,” the focus shifted to cracking down on gang activity, and Bitcoin investments suffered due to market crashes.

IMF’s Reaction to El Salvador’s Bitcoin Adoption

• The IMF’s executive directors urged the country to narrow the scope of the Bitcoin law and remove Bitcoin’s legal tender status.
• The adoption of Bitcoin by El Salvador might have an impact on the country’s application for a $1.3 billion loan from the IMF.

IMF’s Evolving Stance on Cryptocurrency and CBDCs

• Despite its initial reservations, the IMF recently published a blog post acknowledging the growing interest in cryptocurrency and CBDCs in Latin America and the Caribbean.
• The IMF stated that completely banning crypto assets may not be effective in the long run and called for improved financial infrastructure and regulatory measures.
• The post highlighted the importance of transparency by recording crypto transactions and emphasized the need for regulation in the crypto space.

Difference between Cryptocurrency and CBDCs

• Cryptocurrencies, like Bitcoin, are decentralized digital currencies managed by private entities or individuals.
• CBDCs, on the other hand, are blockchain-based digital currencies controlled and tracked by a country’s central bank, corresponding to its fiat currency.
• While cryptocurrencies can experience significant price volatility and are often seen as investment vehicles, CBDCs aim to mirror the value of their physical counterparts and serve as digital representations of fiat currencies.

Examples of CBDCs

• The eNaira, issued by the Central Bank of Nigeria, is an example of a CBDC that aims to mirror the value of Nigeria’s fiat currency. China has actively promoted its digital currency, the digital renminbi (e-RMB), with transaction volumes crossing $13.9 billion in 2022. China has also banned crypto mining and unregulated virtual assets, leading many miners to relocate to other countries.