New laser technology can make objects invisible

Agencies
September 14, 2017

London, Sept 14: Scientists have developed a cloaking technology that can make opaque materials invisible by using light waves from lasers, paving the way for novel ways of camouflaging objects.

A completely opaque material is irradiated from above with a specific wave pattern - with the effect that light waves from the left can pass through the material without any obstruction.

The technique can be applied to different kinds of waves, and should work with sound waves just as well as with light waves, researchers said.

"Complex materials such as a sugar cube are opaque, because light waves inside them are scattered multiple times," said Stefan Rotter, from Technische Universitat Wien (TU Wien) in Austria.

"A light wave can enter and exit the object, but will never pass through the medium on a straight line. Instead, it is scattered into all possible directions," said Rotter.

For years many different attempts have been made to outwit this kind of scattering, creating a "cloak of invisibility."

Special materials have been worked out, for example, which are able to guide light waves around an object. Alternatively, also experiments have been performed with objects that can emit light by themselves.

When an electronic display sends out exactly the same light as it absorbs in the back, it can appear invisible, at least when looked at in the right angle.

"We did not want to reroute the light waves, nor did we want to restore them with additional displays. Our goal was to guide the original light wave through the object, as if the object was not there at all," said Andre Brandstotter, one of the authors of the study.

"This sounds strange, but with certain materials and using our special wave technology, it is indeed possible," said Brandstotter.

To make the laser shine, energy has to be supplied by means of a pump beam. Otherwise, the laser material behaves just like any other material - it absorbs part of the incident light.

"The crucial point is to pump energy into the material in a spatially tailored way such that light is amplified in exactly the right places, while allowing for absorption at other parts of the material," said Konstantinos Makris from the University of Crete in Greece.

"To achieve this, a beam with exactly the right pattern has to be projected onto the material from above - like from a standard video projector, except with much higher resolution," said Makris.

If this pattern perfectly corresponds to the inner irregularities of the material which usually scatter the light, then the projection from above can effectively switch off the scattering, and another beam of light travelling through the material from one side can pass without any obstruction, scattering or loss.

"Mathematically, it is not immediately obvious that it is at all possible to find such a pattern," said Rotter.

"Every object we want to make transparent has to be irradiated with its own specific pattern - depending on the microscopic details of the scattering process inside," he said.

"The method we developed now allows us to calculate the right pattern for any arbitrary scattering medium," he added.

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Agencies
February 27,2020

Feb 27: With the window to submit comments on India's proposed personal data protection law closing on Tuesday, a period of anxious wait for final version of the Bill started for social media firms.

This comes even as global Internet companies have called on the government for improved transparency related to intermediary Guidelines (Amendment) Rules and allay fears about the prospect of increased surveillance and prompting a fragmentation of the Internet in India that would harm users.

As per the proposed amendments, an intermediary having over 50 lakh users in the country will have to be incorporated in India with a permanent registered office and address.

When required by lawful order, the intermediary shall, within 72 hours of communication, provide such information or assistance as asked for by any government agency or assistance concerning security of the state or cybersecurity.

This means that the government could pull down information provided by platforms such as Wikipedia, potentially hampering its functioning in India.

In the open letter to IT Minister Ravi Shankar Prasad, leading browser and software development platform like Mozilla, Microsoft-owned GitHub and Cloudflare earlier called for improved transparency by allowing the public an opportunity to see a final version of these amendments prior to their enactment.

According to a Business Insider report, Indian users may lose access to Wikipedia if the new intermediary rules for internet and social media companies are approved.

Since the rules would require the website to take down content deemed illegal by the government, it would require Wikipedia to show different content for different countries.

Anusha Alikhan, senior communications director for Wikimedia told Business Insider that the platform is built though languages and not geographies. Therefore, removing content from one country, while it is still visible to other country users may not work for the company’s model.

India is one of Wikipedia’s largest markets. Over 771 million Indian users accessed the site in just November 2019.

Also read: Explained: What is the Personal Data Protection Bill and why you should care

The Personal Data Protection Bill, 2019, which was introduced in Lok Sabha in the winter session last year, was referred to a Joint Parliamentary Committee (JPC) of both the Houses.

The government last month decided to seek views and suggestions on the Bill from individuals and associations and bodies concerned and the last date for submitting the comments was on Tuesday.

Prasad, while introducing the Personal Data Protection Bill, 2019, in the Lok Sabha on December 11, announced that the draft Bill empowers the government to ask companies including Facebook, Google and others for anonymised personal data and non-personal data.

There was a buzz when the Bill's latest version was introduced in the Lok Sabha, especially the provision seeking to allow the use of personal and non-personal data of users in some cases, especially when national security is involved.

Several legal experts red-flagged the issue and said the provision will give the government unaccounted access to personal data of users in the country.

In their submission to the JPC, several organisations also flagged that the power to collect non-personal and anonymised data by the government without notice and consent should not form part of the Bill because of issues regarding effective anonymisation and potential abuse.

"Clauses 35 and 36 of the Bill provide unbridled access to personal data to the Central Government by giving it powers to exempt its agencies from the application of the Bill on the basis of various broad worded grounds," SFLC.in, a New Delhi-based not-for-profit legal services organisation, commented.

The Software Alliance, also known as BSA, a trade group which includes tech giants such as Microsoft, IBM and Adobe, among others said that the current version of the privacy bill pose substantial challenges, including the sweeping new powers for the government to acquire non-personal data, restrictions on data transfers, and local storage requirements.

"We urge the Joint Parliamentary Committee, as it considers revisions to the Bill, to eliminate provisions concerning non-personal data from the Personal Data Protection Bill and to remove the data localisation requirements and restrictions on international data flows," said Venkatesh Krishnamoorthy, Country Manager-India, BSA.

The Personal Data Protection (PDP) Bill, 2019 draws its origins from the Justice B.N. Srikrishna Committee on data privacy, which produced a draft of legislation that was made public in 2018 ("the Srikrishna Bill").

The mandatory requirement for storing a mirror copy of all personal data in India as per Section 40 of the Srikrishna Bill has been done away with in the PDP Bill, 2019, meaning that companies like Facebook and Twitter would be able to store data of Indian users abroad if they so wish.

But the bill prohibits processing of sensitive personal data and critical personal data outside India.

What is more, what constitutes critical data has not been clearly defined.

As per the proposals, social media companies will have to modify their application as they are required to have a system in place by which a user can verify themselves.

So legal experts believe that some system to upload identification documents should be there and something like the Twitter blue tick mark should be there to identify verified accounts.

"The 2019 Bill introduces a new category of data fiduciaries called social media intermediaries ('SMIs'). SMIs are a subcategory of significant data fiduciaries ('SDFs') and will be notified by the Central government after due consultation with the DPA, or the Data Protection Authority. Clause 26(4) of the Bill defines SMIs as intermediaries who primarily or solely enable online interaction between two or more users," SFLC.in said.

"On a plain reading of the definition, online platforms like Facebook, Twitter, YouTube, TikTok, ShareChat and WhatsApp are likely to be notified as SMIs under the Bill," it added.

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News Network
March 13,2020

Bengaluru, Mar 13: In the wake of fresh cases of Covid-19 reported in Karnataka, Infosys Foundation chairperson Sudha Murty has urged the Karnataka government to take steps to shut malls and theatres, saying the coronavirus multiplies in air-conditioned areas.

In a letter to the government, she said preventive measures should be taken to control the spread of coronovirus before it gets worse.

Murty, who also leads the State government-constituted Karnataka Tourism Task Force, said she has discussed the current situation with Chairman and Executive Director of Narayana Health, Devi Prasad Shetty.

She suggested closure of all schools and colleges with immediate effect, malls, theatres and “all air-conditioned areas where the virus multiplies”, and allow only essential services like pharmacy, grocery and petrol bunks.

“It is not scientifically proven that the virus dies in high temperature,” she said pointing to spread of the virus -- despite heat -- in peak summer in Australia and Singapore, which have “summer all 12 months”.

“I request you to vacate one government hospital with at least 500 - 700 beds for this purpose (to deal with coronavirus cases), which requires oxygen lines and pipes,” she said.

“Infosys Foundation, the philanthropic and CSR arm of software major Infosys, would do the civil work and Devi Shetty has agreed to share resources like medical equipment,” she added.

“We would like to work with the government proactively so that we can prevent this as early as possible,” Sudha Murty said.

The total number of confirmed coronavirus positive cases in Karnataka is five, including the 76-year old man from Kalaburagi who died on Tuesday night.

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Agencies
March 21,2020

The World Health Organisation (WHO) on Saturday launched a Health Alert on WhatsApp where over 1.5 billion users can ask questions and they will be provided with reliable information about new coronavirus 24/7.

This will also serve government decision-makers by providing the latest numbers and situation reports, WhatsApp said in a statement.

To contact the WHO Health Alert, save the number +41 79 893 1892 in phone contacts, and then simply text the word 'Hi' in a WhatsApp message to get started.

The service responds to a series of prompts and will be updated daily with the latest information.

"You can also visit the WhatsApp Coronavirus Information Hub at whatsapp.com/coronavirus," and click on the WHO link on the homepage to open up a chat with the WHO Health Alert if you have WhatsApp installed," said the micro-blogging platform.

The WHO Health Alert will provide official information on topics such as how to protect yourself from infection, travel advice, and debunking new coronavirus myths.

The service is initially launching in English but will be available in all six languages within the coming weeks (English, Arabic, Chinese, French, Russian and Spanish.)

"Digital technology gives us an unprecedented opportunity for vital health information to go viral and spread faster than the pandemic. We are proud to have partners like Facebook and WhatsApp, that are supporting us in reaching billions of people with important health information," said Dr Tedros Adhanom Ghebreyesus, Director-General of the WHO.

The WHO Health Alert is the latest official NGO or government helpline to become available on WhatsApp, joining the Singapore Government, The Israel Ministry of Health, the South Africa Department of Health, and KOMINFO Indonesia.

Earlier this week, WhatsApp, in partnership with the World Health Organization, UNICEF, and UNDP, launched the WhatsApp Coronavirus Information Hub. The hub offers general tips and resources for users around the world to reduce the spread of rumours and connect with accurate health information.

WhatsApp also announced a $1 million grant to the International Fact Checking Network to support fact-checking for the #CoronaVirusFacts Alliance.

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