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Subject: Science and Technology

  • [pib] Petascale Supercomputer “PARAM Ganga” established at IIT Roorkee

    The National Supercomputing Mission (NSM) has now deployed “PARAM Ganga”, a supercomputer at IIT Roorkee, with a supercomputing capacity of 1.66 Petaflops.

    What is a Supercomputer?

    • A supercomputer is a computer with a high level of performance as compared to a general-purpose computer.
    • The performance of a supercomputer is commonly measured in floating-point operations per second (FLOPS) instead of million instructions per second (MIPS).
    • Since 2017, there are supercomputers which can perform over a hundred quadrillion FLOPS (peta FLOPS).
    • Since November 2017, all of the world’s fastest 500 supercomputers run Linux-based operating systems.

    PARAM Ganga

    • PARAM Ganga is designed and commissioned by C-DAC under Phase 2 of the build approach of the NSM.
    • It is based on a heterogeneous and hybrid configuration of Intel Xeon Cascade lake processors, and NVIDIA Tesla V100.
    • There are 312 (CPU+GPU+HM) nodes with a total peak computing capacity of 1.67 (CPU+GPU+HM) PFLOPS performance.
    • The cluster consists of compute nodes connected with the Mellanox (HDR) InfiniBand interconnect network.
    • The system uses the Lustre parallel file system and operating system is CentOS 7.x.

    Back2Basics: National Supercomputing Mission (NSM)

    • NSM is a proposed plan by GoI to create a cluster of seventy supercomputers connecting various academic and research institutions across India.
    • In April 2015 the government approved the NSM with a total outlay of Rs.4500 crore for a period of 7 years.
    • The mission was set up to provide the country with supercomputing infrastructure to meet the increasing computational demands of academia, researchers, MSMEs, and startups by creating the capability design, manufacturing, of supercomputers indigenously in India.
    • Currently there are four supercomputers from India in Top 500 list of supercomputers in the world.

    Aims and objectives

    • The target of the mission was set to establish a network of supercomputers ranging from a few Tera Flops (TF) to Hundreds of Tera Flops (TF) and three systems with greater than or equal to 3 Peta Flops (PF) in academic and research institutions of National importance across the country by 2022.
    • This network of Supercomputers envisaging a total of 15-20 PF was approved in 2015 and was later revised to a total of 45 PF (45000 TFs), a jump of 6 times more compute power within the same cost and capable of solving large and complex computational problems.

    When did India initiate its efforts to build supercomputers?

    • India’s supercomputer program was initiated in the late 1980s, when the United States ceased the export of a Cray Supercomputer due to technology embargos.
    • This resulted in India setting up C-DAC in 1988, which in 1991, unveiled the prototype of PARAM 800, benchmarked at 5 Gflops. This supercomputer was the second-fastest in the world at that time.
    • Since June 2018, the USA’s Summit is the fastest supercomputer in the world, taking away this position from China.
    • As of January 2018, Pratyush and Mihir are the fastest supercomputers in India with a maximum speed of Peta Flops.

    What are the phases of the National Supercomputing Mission?

    Phase I:

    • In the first phase of the NSM, parts of the supercomputers are imported and assembled in India.
    • A total of 6 supercomputers are to be installed in this phase.
    • The first supercomputer that was assembled indigenously is called Param Shivay. It was installed in IIT (BHU) located in Varanasi.
    • Similar systems, Param Shakti (IIT Kharagpur) and Param Brahma (IISER, Pune) were also later installed within the country.
    • The rest will be installed at IIT Kanpur, IIT Hyderabad and Jawaharlal Nehru Institute of Advanced Studies (JNIAS).

    Phase II:

    • The supercomputers that are installed so far are about 60% indigenous.
    • The 11 systems that are going to be installed in the next phase will have processors designed by the Centre for Development of Advanced Computing (C-DAC) and will have a cumulative capacity of 10 petaflops.
    • These new systems are to be constructed more cost-effectively than the previous ones.
    • One of the 11 proposed supercomputers will be installed
    • at C-DAC exclusively for small and medium enterprises so that they can train employees as well as work on supercomputers at a very low cost.

    Phase III:

    • The third phase aims to build fully indigenous supercomputers.
    • The government had also approved a project to develop a cryogenic cooling system that rapidly dispels the heat generated by a computing chip. This will be jointly built together by IIT-Bombay and C-DAC.

     

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  • Protocols for social media

    Context

    The lack of clear systems within social media companies that claim to connect the world is appalling. It is time that they should have learned from multiple instances, as recent as the Israeli use of force in Palestine.

    Role of social media platforms in the context of conflict

    • There was no unpredictability over conflicts in the information age spilling over to social media platforms.
    • In the context of conflict, social media platforms have multiple challenges that go unaddressed.
    • Threat of information warfare: Content moderation remains a core area of concern, where, essentially, information warfare can be operationalised and throttled.
    • Their sheer magnitude and narrative-building abilities place a degree of undeniable onus on them.
    • After years of facing and acknowledging these challenges, most social media giants are yet to create institutional capacity to deal with such situations.
    • Additionally, they also act as a conduit for further amplification of content on other platforms.
    • Major social media platforms such as Facebook, Instagram, and Twitter also provide space for extremist views from fringe platforms, where the degree of direct relation to the user generating such content is blurred.

    Technology falls short

    • Misinformation and disinformation are thorny challenges to these platforms.
    • Algorithmic solutions are widely put to use to address them.
    • These include identification of content violative of their terms, reducing the visibility of content deemed inappropriate by the algorithm, and in the determination of instances reported to be violative of the terms by other users.
    • More often than not in critical cases, these algorithmic solutions have misfired, harming the already resource-scarce party.
    • The operational realities of these platforms require that the safety of users be prioritised to address pressing concerns, even at the cost of profits.

    Lessons for India

    • The lack of coherent norms on state behaviour in cyberspace as well as the intersection of business, cyberspace, and state activity is an opportunity for India.
    • Indian diplomats can initiate a new track of conversations here which can benefit the international community at large.
    • India should ensure that it initiates these conversations through well-informed diplomats.
    • Finally, it is necessary to reassess the domestic regulatory framework on social media platforms.
    • Transparency and accountability need to be foundational to the regulation of social media platforms in the information age.

    Conclusion

    It is in our national interest and that of a rule-based global polity that social media platforms be dealt with more attention across spheres than with a range of reactionary measures addressing immediate concerns alone.

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  • Filling the physical gaps in India’s digital push

    Context

    A lot has been written about the emphasis on “digital” in the 2022 Union Budget. But one aspect that hasn’t been talked about as much is the importance given in the budget to digital public infrastructure (DPI).

    Significance of digital public infrastructure (DPI) in India

    • A global trendsetter: India is seen as a global trendsetter in the DPI movement, having set up multiple large-scale DPIs like Aadhaar, UPI and sector-specific platforms like DIGIT for eGovernance and DIKSHA for education.
    • Improvement in public service delivery: These DPIs have helped push the frontier of public service delivery.
    • Four key announcements in Budget: This year’s budget adds to the growing discourse on DPIs by making four key announcements:
    • 1] In health, an open platform with digital registries, a unique health identity and a robust consent framework;
    • 2] In skilling, a Digital Ecosystem for Skilling and Livelihood (DESH-Stack) to help citizens upskill through online training;
    • 3] a Unified Logistics Interface Platform (ULIP) to streamline movement of goods across modes of transport; and for travel,
    • 4] In mobility, an “open source” mobility stack for facilitating seamless travel of passengers.
    • Analysis by the Centre for Digital Economy Policy Research (C-DEP) estimates that national digital ecosystems could add over 5 per cent to India’s GDP.

    Suggestions

    • But important design considerations must be set right if we are to truly unlock the value of these platforms.

    1] Differentiating between tech and non-tech layer

    • We need to differente between the “tech” and “non-tech” layers of our digital infrastructure.
    • While India seems to have made significant headway on the “tech” layers, the “non-tech” layers of community engagement and governance need a lot more work.
    • The combination of these three layers is what is critical to making tech work for everyone.
    • Together, they embody what we call the open digital ecosystems (ODE) approach.

    2] Get non-tech layers right

    • To unleash the true potential of India’s ODEs, we need to get the “non-tech” layers right, by prioritising principles around data protection, universal access and accountability.
    • In this regard, three specific non-tech levers are critical.
    • 1] Data protection: Protecting the data of all users and giving them agency over how their data gets used.
    • The passage of a robust Data Protection Bill is imperative.
    • But we also need to go beyond the mere requirement of “consent”.
    • 2] Address digital divide: It is important to address the digital divide.
    • Research by ORF, for instance, shows that Indian women are 15 per cent less likely to own a mobile phone and 33 per cent less likely to use mobile internet services than men.
    • So, we need a “phygital” approach that provides services through both online and offline options and strong grievance redressal mechanisms.
    • 3] Institutional mechanism: As we push the frontier on digitisation, India must also focus on developing anchor institutions and robust governance frameworks.
    • Just as Aadhaar is anchored by UIDAI under an Act of Parliament, and the Ayushman Bharat Digital Mission is anchored by the National Health Authority, every new ODE requires an accountable institutional anchor. 
    • These institutions are critical for setting standards, ensuring a level playing field and safeguarding consumer interest.

    Consider the question “India is seen as a global trendsetter in the DPI movement, having set up multiple large-scale Digital Public Infrastructures(DPI). List the various DPIs in various sectors in India. Suggest the changes needed in the non-tech layers of these DPIs.”

    Conclusion

    From Aadhaar and UPI to DBT and CoWin, India’s tech stacks are grabbing global attention. It is now critical to bring the gaze on to the non-tech layers of the stack, so that the potential of these platforms can be unlocked for every Indian.

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  • Kavach: the Indian technology that can prevent collision of Trains

    Kavach, this indigenously developed Automatic Train Protection System is earmarked for aggressive rollout on 2,000 km in 2022-23, according the Budget proposals.

    What is Kavach?

    • It is India’s very own automatic protection system in development since 2012, under the name Train Collision Avoidance System (TCAS), which got rechristened to Kavach or “armour”.
    • Simply put, it is a set of electronic devices and Radio Frequency Identification devices installed in locomotives, in the signalling system as well the tracks.
    • They connect to each other using ultra high radio frequencies to control the brakes of trains and also alert drivers, all based on the logic programmed into them.

    Key features of Kavach

    • One of its features is that by continuously refreshing the movement information of a train, it is able to send out triggers when a loco pilot jumps signal, called Signal Passed at Danger (SPAD).
    • The devices also continuously relay the signals ahead to the locomotive, making it useful for loco pilots in low visibility, especially during dense fog.
    • It includes the key elements from already existing, and tried and tested systems like the European Train Protection and Warning System, and the indigenous Anti Collison Device.
    • It will also carry features of the high-tech European Train Control System Level-2 in future.
    • The current form of Kavach adheres to the highest level of safety and reliability standard called Safety Integrity Level 4.

    What is the upgrade?

    • In the new avatar, India wants to position Kavach as an exportable system, a cheaper alternative to the European systems in vogue across the world.
    • While now Kavach uses Ultra High Frequency, work is on to make it compatible with 4G Long Term Evolution (LTE) technology and make the product for global markets.
    • Work is on to make the system such that it can be compatible with other already installed systems globally.

    How far is the rollout?

    • So far, Kavach has been deployed on over 1,098 km and 65 locomotives in ongoing projects of the South Central Railway.
    • In future it will be implemented on 3000 km of the Delhi-Mumbai and Delhi-Howrah corridors where the tracks and systems are being upgraded to host a top speed of 160 kmph.
    • Further, over 34,000 km on the High Density Network (HDN) and Highly Utilized Network (HUN) of on the Golden Quadrilateral have been included in its sanctioned plans.

     

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  • What are Cluster Bombs and Thermobaric Weapons?

    Human rights group Amnesty International has accused Russia of using cluster bombs and vacuum bombs in the ongoing war.

    What are Cluster Munitions?

    • According to the 2008 Convention on Cluster Munitions, a cluster munition means a “conventional munition that is designed to disperse or release explosive submunitions each weighing less than 20 kilograms, and includes those explosive submunitions”.
    • Essentially, cluster munitions are non-precision weapons that are designed to injure or kill human beings indiscriminately over a large area.
    • They are often designed to destroy vehicles and infrastructure such as runways, railway or power transmission lines.
    • They can be dropped from an aircraft or launched in a projectile that spins in flight, scattering many bomblets as it travels.
    • Many of these bomblets end up not exploding, but continue to lie on the ground, often partially or fully hidden and difficult to locate and remove, posing a threat to the civilian population.
    • The Convention on Cluster Munitions specifically identifies “cluster munition remnants”, which include “failed cluster munitions, abandoned cluster munitions, unexploded submunitions and unexploded bomblets”.

    And what is a Thermobaric Weapon?

    • Thermobaric weapons — also known as aerosol bombs, fuel air explosives, or vaccum bombs — use oxygen from the air for a large, high-temperature blast.
    • A thermobaric weapon causes significantly greater devastation than a conventional bomb of comparable size.
    • The weapons, which go off in two separate stages, can be fired as rockets from tank-mounted launchers or dropped from aircraft.
    • As they hit their target, a first explosion splits open the bomb’s fuel container, releasing a cloud of fuel and metal particles that spreads over a large area.
    • A second explosion then occurs, igniting the aerosol cloud into a giant ball of fire and sending out intense blast waves that can destroy even reinforced buildings or equipment and vaporise human beings.

    Is it legal to use these weapons?

    • Countries that have ratified the Convention on Cluster Munitions are prohibited from using cluster bombs.
    • As of date, there are 110 state parties to the convention, and 13 other countries have signed up but are yet to ratify it.
    • Neither Russia nor Ukraine are signatories.
    • These bombs are not prohibited by any international law or agreement, but their use against civilian populations in built-up areas, schools or hospitals, could attract action under the Hague Conventions of 1899 and 1907.
    • International humanitarian law prohibits the use of inherently indiscriminate weapons such as cluster munitions.
    • Launching indiscriminate attacks that kill or injure civilians constitutes a war crime.

     

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  • Antonov AN-225: World’s largest aircraft

    Amid Moscow’s assault on Ukraine, the world’s largest cargo aircraft, the Antonov AN-225 or ‘Mriya’, was destroyed by Russian troops during an attack on an airport near Kyiv.

    Antonov AN-225

    • With a wingspan of over 290-feet, the unique Antonov AN-225 was designed in what was then the Ukrainian USSR during the 1980s amid a tense race to space between the US and the Soviet Union.
    • The plane, nicknamed ‘Mriya’ or ‘dream’ in Ukrainian, is very popular in aviation circles, and is known to attract huge crowds of fans at air shows around the world.
    • It was initially designed as part of the Soviet aeronautical program to carry the Buran, which was the Soviet version of the US’ Space Shuttle.
    • After the collapse of the Soviet Union in 1991, when the Buran program was cancelled, the aircraft was instead used to transport massive cargo loads.

    Its manufacturing

    • Only one AN-225 was ever built by the Kyiv-based Antonov Company, the defence manufacturers who originally designed the plane.
    • It is essentially a large version of another design by the Antonoc Company — the four-engine An-124 ‘Condor’, which is used by the Russian Air Force.
    • The aircraft first took flight in 1988 and has been in use ever since.
    • In the recent past, it has been used for delivering relief supplies during calamities in neighbouring nations.

     

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  • NASA to decommission the International Space Station

    The National Aeronautics and Space Administration (NASA) has announced plans to retire and decommission the International Space Station (ISS) by 2031.

    What is the ISS?

    • The ISS was launched in 1998 as part of joint efforts by the U.S., Russia, Japan, Canada and Europe.
    • The idea of a space station originated in the 1984 State of the Union address by former U.S. President Ronald Reagan.
    • The space station was assembled over many years, and it operates in low-earth orbit.
    • Since its inception, it has served as a laboratory suspended in space and has aided multiple scientific and technological developments.
    • The ISS was originally built to operate for 15 years.

    Why was ISS launched?

    • A space station permits quantum leaps in research in science, communications, and in metals and lifesaving medicines which could be manufactured only in space.
    • ISS has consistently maintained human presence for the past 21 years, providing astronauts with sophisticated technologies for scientific research.

    Why is NASA planning to decommission the ISS?

    • The space station has already surpassed that checkpoint by being active for 21 years, with plans to continue operations till 2030.
    • The ISS goes through 16 rotations of the earth per day, causing extreme temperature changes on the exterior.
    • The side facing the sun can get heated up to 121°C while the temperature on the opposite, darker side can fall to –157°C, causing intense expansion and contraction of the building material.
    • This orbital thermal cycling, coupled with dynamic loading, affects the longevity of the primary structure of the space station.
    • The technical lifetime is also limited by parts like radiators, modules and truss structures that tend to degrade over time.

    What is the procedure to de-orbit the ISS?

    • NASA plans to remove the ISS from its orbit around the earth and eventually plunge it into the ocean at a point farthest from human civilisation.
    • The space agency will use the dual method of natural orbit decay and a re-entry manoeuvre to bring an end to the ISS as we know it.
    • According to the plan, the earth’s natural atmospheric drag will be used in lowering the altitude of the ISS while setting up the de-orbit.
    • The space station operators will then provide the final push to it to lower the structure to the maximum possible height and ensure safe re-entry into the earth’s atmosphere.
    • It would then lead to Point Nemo over the South Pacific Oceanic Uninhabited Area (SPOUA).
    • Dissembling process would have posed huge logistical and financial challenges.

    How big is it?

    • The ISS is a huge structure — almost the size of a football field — and it was not designed to be disassembled easily in space.
    • The station currently operates in low-earth orbit above 400 km in altitude, at a point where it still experiences atmospheric drag and requires re-boosts to continue in its orbit.
    • The station also has a mass of over 4,30,000 kg.
    • Existing propulsion systems do not have the capacity to raise the station’s altitude to a high target and escape low-earth orbit.
    • The random re-entry method was discarded since it carries a huge risk for the human population on the ground.

    What is the future of space stations?

    • As the ISS plans to end operations in space, new players are already lining up to replace it.
    • In January 2022, China announced that its space station will be ready for operations this year.
    • Blue Origin, the aerospace company founded by Jeff Bezos, has also announced its plans to build Orbital Reef, a commercially developed, owned, and operated space station in low-earth orbit.
    • Blue Origin is working alongside Sierra Space on the project.

     

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  • [pib] Quantum Key Distribution

    A joint team of scientists from DRDO and IIT Delhi, for the first time in the country successfully demonstrated Quantum Key Distribution (QKD) link between Prayagraj and Vindhyachal in Uttar Pradesh, a distance of more than 100 kilometers.

    What is QKD Technology?

    • Quantum key distribution (QKD) is a secure communication method that implements a cryptographic protocol involving components of quantum mechanics.
    • It enables two parties to produce a shared random secret key known only to them, which can then be used to encrypt and decrypt messages.
    • It gives the ability of the two communicating users to detect the presence of any third party trying to gain knowledge of the key.
    • This is a result of a fundamental aspect of quantum mechanics: the process of measuring a quantum system, in general, disturbs the system.
    • By using quantum superposition or quantum entanglement and transmitting information in quantum states, a communication system can be implemented that detects data leak.

    How does it work?

    • QKD works by transmitting many light particles, or photons, over fiber optic cables between parties.
    • Each photon has a random quantum state, and collectively, the photons sent make up a stream of ones and zeros.
    • This stream of quantum states that make up ones and zeros are called qubits — the equivalent of bits in a binary system.
    • When a photon reaches its receiving end, it will travel through a beam splitter, which forces the photon to randomly take one path or another into a photon collector.
    • The receiver will then respond to the original sender with data regarding the sequence of the photons sent, and the sender will then compare that with the emitter, which would have sent each photon.

    Benefits offered

    • It allows the detection of data leak or hacking because it can detect any such attempt.
    • It also allows the process of setting the error level between the intercepted data in dependence.

     

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  • All you need to know about Satellite Internet

    The Reliance has launched a joint venture (JV) with European satellite-based broadband service company SES to enter the satellite internet space.

    What is Satellite Internet?

    • The technology beams the internet down from a satellite that’s orbiting the Earth.
    • Jio, Bharti Airtel Ltd’s OneWeb, and billionaire Elon Musk’s Starlink want to send thousands of these satellites to orbit.
    • OneWeb plans to launch 648 satellites, while Musk’s Starlink has permits to launch over 4,000 of them.
    • So far, OneWeb has launched over 400 satellites, while Starlink has launched over 2,000 satellites.
    • It’s worth noting that Starlink plans to launch 42,000 satellites in the coming decade. Jio’s journey has only just begun.

    Which satellites will Indian JV use?

    • The JV will use geostationary (GEO) and medium earth orbit (MEO) satellites, while Starlink and OneWeb use low earth orbit (LEO) satellites.
    • LEO satellites are cheaper to make and deploy, but require a satellite constellation working in sync to offer coverage on earth.
    • On the other hand, GEO and MEO satellites are larger, deployed in higher orbits, and therefore cost more.
    • These satellites cover a larger area and require fewer ground stations, which makes them ideal for targeted coverage area.
    • LEOs move faster and can hence provide global coverage.

    What are the advantages of satellite internet?

    • The reason telecom firms want to explore satellite internet is because there are areas where fibre connections just can’t reach.
    • Satellite networks are used to bring connectivity in such areas, which include hills and remote islands.
    • Consumer applications are new, but satellite networks have been used for ages in military applications.

    Are there any disadvantages?

    • The applications and the power of satellite internet are often exaggerated.
    • In reality, these networks have limitations, the biggest being high latency and low bandwidths.
    • Latency is all about internet speed, while bandwidth determines how many devices can connect on a network at the same time.
    • Experts say current satellite connections will bring 1-2 MB bandwidth, which just about qualifies as broadband under India’s broadband policy.
    • Trouble-shooting can be a problem because it needs specialized knowledge.

    Who can use satellite internet?

    • Militaries across the world have depended on satellite communications for a long time.
    • However, many military experts, too, consider this form to be unreliable and too expensive to be made the sole communication medium.
    • In remote areas, satellite internet can still allow businesses to open up local branches and provide digital services.
    • In theory, a bank could set up more ATMs in remote regions if it has access to satellite internet.

     

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  • Can dark matter be composed, even partly, of black holes?

    A recent hypothesis says that dark matter comprises a large number of compact objects such as primordial black holes.

    What are Dark Matters ?

    • Astronomical observations suggest that a significant part of the universe is made up of dark matter which interacts with the rest of the universe only through the gravitational pull.
    • Many large lab experiments have tried to detect elementary particles that could be candidates for dark matter.
    • However, such dark matter particles have not been detected until now.
    • Several astronomical observations suggest that all galaxies are embedded in a “halo” of dark matter.
    • The “visible” galaxy is like a disc embedded in a dark matter halo that is much larger in size.

    What is the recent proposition?

    • When the universe was very young, hot and dense – soon after the Big Bang, it must have had quantum fluctuations of its density.
    • This, in turn, would have caused some regions to become extremely dense, and therefore, to collapse under their own gravity to form the primordial black holes.
    • While we have no conclusive evidence of spotting these objects, some of the binary black hole mergers detected by the LIGO gravitational wave detectors might be primordial black holes.
    • The question is open there is good reason to believe that primordial black holes did form in the young universe.

    Observing dark matter: Gravitational Lensing

    • The paper explores what happens when such objects get in the way of gravitational waves traveling towards the Earth from the distance.
    • It invokes a phenomenon called gravitational lensing that is used regularly in astronomy.
    • When light travels through space and passes near a massive or compact body – a star, a galaxy or a black hole, for example, the intense gravity of that body may attract the light towards it.
    • This causes bending it from its rectilinear (straight line) path.
    • This phenomenon is known as gravitational lensing and was first observed by Arthur Eddington in 1919.

    How intense are they?

    • Massive objects like galaxies can bend light significantly, producing multiple images, this is called strong lensing.
    • Lighter objects like stars or black holes bend light less, and this is called micro-lensing.
    • A similar lensing can happen to gravitational waves travelling towards the Earth, and this would leave signatures in the detected gravitational waves.
    • This can be used to detect the presence, or the existence, of primordial black holes.

    Assessing dark matter

    • Until now, individual black holes have not marked out these signatures on gravitational waves detected by the LIGO-VIRGO detectors.
    • However, if all of the dark matter is made of primordial black holes, they should have produced detectable signatures on the gravitational wave signals.
    • The researchers use the non-observation of the lensing signatures to assess what fraction of the dark matter could be made of black holes.

    Way ahead

    • This provides a new way of constraining the nature of dark matter.
    • The study concludes that black holes in the mass range from a hundred to a million solar masses can contribute only up to 50-80% of the dark matter in the universe.
    • This is an upper limit and the actual fraction can be much smaller.
    • These upper limits will get better and better with more and more observations.

     

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