APTN National News OTTAWA–Assembly of First Nations National Chief Perry Bellegarde said he met with Aboriginal Affairs Minister Bernard Valcourt on Wednesday and discussed the deadly fire on a Saskatchewan First Nation that left two children dead.The two met as a result of last week’s deadly fire on the Makwa Sahgaiehcan First Nation.“Any death in communities is tragic, we acknowledged that and we acknowledged that we have to collectively work together to work on solutions,” said Bellegarde.Bellegarde said he met with Valcourt on the fourth floor of Centre Block on Parliament Hill.Valcourt’s office did not return a request for comment on the meeting as of this article’s posting.Valcourt has blamed Makwa Sahgaiehcan First Nation for not having the ability to fight the fire .Bellegarde said in an interview Thursday he wanted to continue to pushing Ottawa on several fronts.“Not only the crisis with fires, but the crisis in housing, the crisis in education,” said Bellegarde. “Basically, we need to start working out our own strategies and solutions to deal with the fiscal imbalance that is there and ensure there is a proper fiscal relationship with the Crown.”email@example.com@APTNNews
Facebook Twitter Google+LinkedInPinterestWhatsAppProvidenciales, TCI, June 30, 2016 – Forty Environmental stewards were honored for contributing their time, equipment and finances to the Department of Environment and Maritime Affairs, DEMA throughout the year. These individuals were both residents and visitors who promoted the observation and helped to create an environmentally sustainable TCI.The Department of Environment and Coastal Resources (D.E.C.R.) hosted the annual Environmental Stewardship Awards at the beginning of the month. DECR Director, Dr John Claydon said The Turks and Caicos Islands is very fortunate to have so many people committed to protecting its wonderful natural environments. He added that, together, the efforts of the honored individuals help keep TCI “beautiful by nature.”Dr. Claydon went on to thank the recipients for their generosity and assistance and encourages the TCI community to sign up and get involved. You can see the list of those honorees at MagneticMediaTV.com, follow, like, link or subscribe. Facebook Twitter Google+LinkedInPinterestWhatsApp Related Items:
WILMINGTON, MA — Below are 5 things to do in Wilmington on Tuesday, January 22, 2019:#1) Wilmington Commission On Disabilities MeetingThe Wilmington Commission on Disabilities meets at 6:30pm in the Town Hall’s Small Conference Room. Read the agenda HERE.#2) Shawsheen Tech School Committee MeetingThe Shawsheen Tech School Committee meets at 7:30pm in the John Miller School Committee Room at the Tech. Read the agenda HERE.#3) Colonial Life For The 18th Century FamilyWindsor Place of Wilmington (92 West Street) is holding a presentation entitled “Colonial Life For The 18th Century Family” at 2:30pm in the Activity Room. In this session, Abigail describes how a colonial family provided for their basic needs. Using primary sources like the family’s probate inventory, learn about which items were important for survival and how they were made. Audience members are encouraged to explore reproduction artifacts just like those that were a part of everyday life. Explore the importance of craftsmen and imported goods. Discover how a family not only survived, but thrived! Open to the public.#4) Creative Writing Skills Group Meeting At LibraryThe Wilmington Memorial Library (175 Middlesex Avenue) is holding a Creative Writing Skills Group Meeting at 7pm. Learn and apply creative writing tips, tools, and techniques shared by published authors and other writing experts. Open to all who want to improve their creative writing skills and get their work published. When registering, please provide your email address so you can receive an agenda and any prep materials in advance. Led by local writing enthusiast, Barbara Alevras. Register HERE.#5) Tech Buddies Drop In At LibraryThe Wilmington Memorial Library (175 Middlesex Avenue) is hosting a Tech Buddies Drop-In from 3:30pm to 4:30pm. Need technology help, but Brad isn’t here? Drop in at a Tech Buddies session! Tech Buddies is a new volunteer program connecting teens and members of the Wilmington community in need of assistance navigating their phones, tablets, cameras, and the Cloud.Like Wilmington Apple on Facebook. Follow Wilmington Apple on Twitter. Follow Wilmington Apple on Instagram. Subscribe to Wilmington Apple’s daily email newsletter HERE. Got a comment, question, photo, press release, or news tip? Email firstname.lastname@example.org.Share this:TwitterFacebookLike this:Like Loading… Related5 Things To Do In Wilmington On Wednesday, June 26, 2019In “5 Things To Do Today”5 Things To Do In Wilmington On Monday, August 26, 2019In “5 Things To Do Today”5 Things To Do In Wilmington On Tuesday, May 28, 2019In “5 Things To Do Today”
TV and Movies The 2019 Oscars were Sunday. If you’re feeling inspired to see some of the winning films you didn’t catch earlier, here’s a guide to where you can stream, rent or buy the majority of them. Sorry in advance, but there are still quite a few you’ll have to catch in theaters — not that you need a movie subscription service to do so, but it can’t hurt. Disclaimer: CNET may get a share of revenue from the sale of the products featured on this page. 40 films (and a tech company) you didn’t know won Oscars For more information on what’s available to watch online, check out CNET.com/Netpicks or subscribe to the podcast — it’s free! And go to CNET sister site TVGuide.com to see what else is out in the world of streaming. Audio (weekly): RSS | iTunes | Google Play Video (monthly): iTunes (HD) | iTunes (HQ) | iTunes (SD) | RSS (HD) | RSS (HQ)| RSS (SD) 42 Photos Best Picture, Best Original Screenplay, Supporting Actor Green Book Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu Best Director, Cinematography, Foreign Language Film Roma Streaming: Netflix Rent/Buy: Nope Best Actor, Sound Mixing, Sound Editing Bohemian Rhapsody Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu Best Costume Design, Production Design, Original Score Black Panther Streaming: Netflix Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Best Adapted Screenplay BlacKkKlansman Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Best Actress The Favourite Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Best Original Song A Star is Born Streaming: Nope Rent/Buy: Google Play, iTunes, YouTube, Microsoft Store, Movies Anywhere Bradley Cooper and Lady Gaga in A Star is Born. Warner Bros Best Supporting Actress If Beale Street Could Talk Streaming: Nope Rent/Buy: Still in theaters Best Makeup and Hairstyling Vice Streaming: Nope Rent/Buy: Still in theaters Best Visual Effects First Man Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Best Animated FilmSpider-Man: Into the Spider-VerseStreaming: NopeRent/Buy: Still in theatersBest Documentary – FeatureFree SoloStreaming: NopeRent/Buy: Amazon, Google Play, iTunes, Vudu, YouTubeBest Documentary – Short SubjectPeriod. End of SentenceStreaming: Netflix Best Animated Short FilmBaoStreaming: NopeRent/Buy: YouTube, Google Play Incredibles 2 Pixar All other nominated films A Quiet Place Streaming: EPIX Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Avengers: Infinity War Streaming: Netflix Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube The Ballad of Buster Scruggs Streaming: Netflix Rent/Buy: Nope Can You Ever Forgive Me? Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Capernaum Streaming: Nope Rent/Buy: Still in theaters Cold War Streaming: Nope Rent/Buy: Still in theaters At Eternity’s Gate Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube First Reformed Streaming: Amazon, KanopyRent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Hale County This Morning, This Evening Streaming: Nope Rent/Buy: Still in theaters Incredibles 2 Streaming: Netflix Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Isle of Dogs Streaming: HBO Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Mary Poppins Returns Streaming: Nope Rent/Buy: Still in theaters Mary Queen of Scots Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes Minding the Gap Streaming: Hulu, PBSRent/Buy: Nope Mirai Streaming: Nope Rent/Buy: Still in theaters Never Look Away Streaming: Nope Rent/Buy: Still in theaters Of Fathers and Sons Streaming: KanopyRent/Buy: Still in theaters Ralph Breaks the Internet Disney Ralph Breaks the Internet Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube RBG Streaming: Hulu, HooplaRent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Ready Player One Streaming: HBO Rent/Buy: Amazon, Google Play, iTunes, Vudu, YouTube Shoplifters Streaming: HooplaRent/Buy: Amazon, iTunes, Vudu, YouTube The Wife Streaming: Nope Rent/Buy: Amazon, Google Play, iTunes, YouTube 0 Post a comment Now playing: Watch this: Stream these 2019 Oscar nominees now 2:33 Tags Share your voice Marvel Target Oscars 2019 Amazon Google Play iTunes Netflix YouTube The Avengers
Share your voice Apr 30 • Facebook’s new Oculus Rift S vs. Oculus Quest: Which VR headset is for you? reading • Qualcomm’s new wireless VR headsets work with PCs, too Like a future Oculus Quest that works with your PCAt last year’s GDC, Qualcomm showed off a next-generation standalone VR headset using a Snapdragon 845 chip and eye tracking. This year’s headset design takes the same chip and adds 802.11ad wireless 60GHz connection, so it can wirelessly connect with a PC and act as its VR headset, too. The wireless connection will have 16ms latency, according to Qualcomm.The PC streams low-latency graphics and game content to the headset, which sends its built-in six degrees of freedom room tracking back to the PC. It’s similar to the way HTC Vive’s wireless PC headset already works. What’s most interesting here, though, is that the VR headset and PC will split processing.Since VR processing will be handled by the PC and the headset’s Snapdragon 845 chip, according to Swart, this means PCs could run VR off lower-end CPUs (but the onboard PC graphics would likely need to be the same). PCs or consoles would need 802.11ad Wi-Fi, and also run Qualcomm software that enables this communication and processing with these upcoming headsets. According to Qualcomm, PC content and games won’t need any alteration at all. A preview of how 5G VR will work?Swart explains the initiative as a stepping stone to eventually having one headset that does both AR and VR, local and wirelessly over 5G. We’re not there yet, but these headsets will connect to PCs in a similar way to how they may connect over 5G in the future.That same split processing is what Qualcomm envisions in future 5G-enabled hardware, mixing some rendering in the cloud and some in-headset. While these headsets are designed to connect to PCs and local devices, eventually they could mix sources from the 5G cloud, local devices and more.The first VR headset with 802.11ad will be the Pico Neo2. Qualcomm One hardware device so farWe don’t know where else this technology will appear, but expect headsets to start arriving this year, according to Qualcomm’s Swart. First up is a Pico Neo2 VR headset that will be “Boundless XR for PC” compatible and have a Snapdragon 845 chip. While the idea of “Boundless for XR” imagines AR and VR devices with wireless tethering, Swart admits that for now, VR headsets will be the major focus, with AR (mixed reality) coming further down the road. Future Snapdragon-enabled AR headsets, such as nReal’s compact glasses, could be possible candidates.The Vive Cosmos, teased at CES in January, remains a mystery but promises similar ideas. CNET Is this what Vive Cosmos is?Qualcomm’s partners so far include software partners Framestore and ZeroLight, hardware partners Pico, Goertek and WNC, and… HTC Vive. Which raises the question: Is this a preview of what the mysterious, multi-connectable Vive Cosmos will be?Qualcomm won’t say, and HTC hasn’t confirmed anything yet. But if this means premium standalone headsets could also connect to PCs wirelessly, then maybe this is what the next generation of VR and AR will look like. This would make sense for the next Microsoft HoloLens (which also runs off a Qualcomm chip) as much as the next Oculus Rift or Vive.Qualcomm’s reference designs have been a pretty good predictor of the future: The company’s standalone Snapdragon 820 headset preceded the Oculus Go. Its Snapdragon 835 standalone reference led to the Lenovo Mirage Solo, HTC Vive Focus and Oculus Quest. Qualcomm already has a parallel vision of the future of AR and VR at Mobile World Congress in Barcelona, with compact, possibly low-cost VR and AR headsets that will plug into 5G phones via USB-C. These newly announced PC-connected standalone wireless headsets look to be larger and more expensive than those USB-C plug-in possibilities. But it suggests that a lot of convergence is on the way for VR and AR in the next few years.CNET will be demoing the tech from GDC, so stay tuned for impressions to come. Apr 30 • How to preorder Oculus Quest and Rift S right now Wearable Tech 16 Photos See All Game Developers Conference • Oculus Quest virtual reality headset revealed Mar 21 • Google Stadia puts Xbox One, PlayStation 4 and PC gaming on notice Tags 2 Game Developers Conference Comments Mar 21 • Intel intros 9th-gen Core H mobile CPUs, Graphics Command Center Qualcomm There are just too many VR helmets and goggles out there — getting even one on your face is enough of a struggle. But Qualcomm’s new vision for its next generation of standalone VR headsets has a solution to that problem. Qualcomm is developing VR headsets that will work as wireless PC-connected, head-mounted displays. Hardware will start arriving later this year, according to Qualcomm, and it’ll be available for demo at this year’s Game Developers Conference in San Francisco.The new initiative, called “Boundless XR for PC,” uses Qualcomm’s Snapdragon 845 processor combined with a wireless 802.11ad chip that will allow high-bandwidth 60GHz connections to a PC or console that’s ready to communicate with it. The VR headset will be a standalone device, like the upcoming Oculus Quest, but when it’s near a PC, it’ll double as a wireless way to play PC games and apps. And it could even hint at where AR headsets such as the HoloLens 2 will head next. Qualcomm’s Hugo Swart explained how it works in a conversation with CNET ahead of GDC. Qualcomm Virtual Reality
“Our study is an important step in understanding how the climate change happening in the remote and inhospitable Antarctic waters will impact the warming of the oceans as a whole and future sea level rise,” explained Professor Alberto Naveira Garabato, who led the project, in a press release.You may remember that “Boaty McBoatface” was the winner of an online contest asking the internet to name a new British polar research vessel. In the end, that ship was instead named in honor of Sir David Attenborough and a small yellow drone sub was christened with the noble McBoatface name instead.Now McBoatface’s legacy has been forever enshrined in the annals of science: the new research is published in the latest edition of Proceedings of the National Academy of Sciences.”This study is a great example of how exciting new technology such as the unmanned submarine ‘Boaty McBoatface’ can be used,” said Dr. Povl Abrahamsen of the British Antarctic Survey.It might be a small little McBoatface, but it still feels as if we all live on that yellow submarine and the whole internet is all aboard. Everybody! We all live in a…. Sci-Tech Culture Online This speedboat can go underwater Post a comment Now playing: Watch this: Share your voice Boaty, seen here on a bigger boaty. Povl Abrahamsen, British Antarctic Survey After all these years, it does sort of feel like we all live on this yellow submarine. The intrepid Boaty McBoatface is back in the news yet again now that the first scientific findings using data from the internet’s fave autonomous sub have been published.Back in April of 2017, the mini-sub with the goofy name spent three days maneuvering through the dark, cold and mountainous waters of the Southern Ocean. Over 180 kilometers (112 miles) it measured the temperature, salt content and turbulence of the water at the bottom of this foreboding sea. Boaty’s data helped scientists make a connection between intensifying winds over the Southern Ocean and rising sea levels. Basically, winds near the bottom of the world have been getting stronger thanks to the Antarctic hole in the ozone layer and rising greenhouse gas emissions. The winds appear to increase turbulence deep in the ocean, as detected by Boaty. This turbulence in turn stirs up colder, denser water from the deep with warmer water above. The resulting warming of the water is a significant contributor to rising sea levels, according to researchers from the UK’s University of Southampton. Boaty don’t need to floaty! Boaty McBoatface dives into first Antarctic mission Boaty McBoatface will set sail after all — in the form of a drone sub RRS Boaty McBoatface could be the UK’s next polar research vessel 0 2:13 Tags
Sundaram Mutual Fund has launched a closed-end income scheme called Sundaram Fixed Term Plan – HT. The issue opened on Wednesday (Aug. 31) and will remain open till Thursday (Sept. 1).The scheme will have a duration of 1,100 days from the date of allotment of units to investors and will invest in debt and money market securities that would mature on or before the maturity of the scheme, according to the offer document.There are two options for investors under the scheme: growth and dividend payout (quarterly and half-yearly). The minimum investment is Rs. 5,000 and in multiples of Rs. 10 thereafter per application.There won’t be any buyback of units given that it is a closed-end scheme. “The Fund will not buy the units back till the maturity of the scheme. However, in order to provide the liquidity to the investors, the units of the Scheme are proposed to be listed on National Stock Exchange of India Limited (NSE) within 5 business days from the date of allotment,” the offer document disclosed.Other details of Sundaram Fixed Term Plan-HT:Entry load: NilExit Load: Not ApplicableDividend will be distributed at the discretion of the Trustee from the available distributable surplus, if any. The dividend when declared will be paid (subject of deduction of tax at source).Unitholders may choose to receive the redemption/dividend proceeds in any of the bank accounts, the details of which are registered with the AMC by specifying the necessary details in the “Bank Accounts Registration form”.Individuals, HUFs, Sole proprietor firms can register up to five bank accounts and other investors can register up to ten bank accounts in a folio.Sandeep Agarwal is the fund manager.On all working days, NAV will be computed (except in special circumstances detailed in the Statement of Additional Information/Scheme (NAV) Publication Information Document) and shall be published in at least two daily newspapers having circulation all over India and updated on the websites of Sundaram Asset Management.
Cyrus Mistry, the ousted chairman of Tata Sons, has started the process of shifting out of Bombay House, which is the headquarters of the Tata Group. The move follows Mistry’s abrupt sacking as the chairman of the $103 billion conglomerate last Monday.”The physical shifting process has started,” a senior Tata Group executive confirmed to the Hindu. He also added that the ousted chairman’s belongings were being removed from his office and the process is believed to end by Monday evening.Mistry’s personal staff is relocating his files and books from the chairman’s office, which is located on the fourth floor in the East wing of Bombay House. Mistry reportedly shifted to Bombay House in 2011 when he was appointed as the deputy chairman of Tata Sons. For one year, Mistry was “groomed” by Ratan Tata regarding the functioning of the Tata Group of companies.Cyrus Mistry was appointed chairman of Tata Sons on December 28, 2012. According to sources quoted by the publication, Mistry was supposed to retain the chairmanship for a long run (until his retirement i.e. for a period of three decades). However, his sudden ouster from the company has left India Inc shocked.In the days following his ouster, the Cyrus Mistry- Rata Tata row has only gotten murkier with allegations flying both ways. According to media reports, the Enforcement Directorate (ED) will probe into Mistry’s allegations related to fraudulent transactions and mismanagement of the Tata Group’s aviation ventures.In a letter addressed to the Tata board, Mistry had alleged that he had opposed to Tata’s aviation partnership with Malaysian-based AirAsia Bhd. “A forensic investigation had found fraudulent transactions of 220 million rupees ($3.29 million) involving non-existent parties,” Mistry’s said.Following Mistry’s removal on the basis of his non-performance, Ratan Tata was named the interim chairman of the Tata Group.
Essar HouseReutersEssar oil’s UK subsidiary, which owns and operates Ellesmere Port-based Stanlow Refinery, on Wednesday said the company is going to invest Rs 1,625 crore ($ 250million) to expand the refining capacity and aiming 400 petrol pumps in Britain in next five years.The oil marketing firm aims to increase its refining capacity from 9.09 million tonnes per annum to 9.7 million tonnes by March 2018, the Economic Times reported.”The investment in revamping of certain units of the refinery would help cut down on crude oil processing cost, improve product slate and lead to marginal increase in capacity,” chief executive S Thangapandian told ET.In revenue terms, the company’s Chief Financial Officer (CFO) P Sampath said revamping would add Rs 65 ($1) to refining margin, translating into Rs 480 crore($70-75 million) in revenue.”The project will deliver enhanced yields of high-value products, reduce crude costs and drive revenue growth,” Thangapandian said.The firm’s net profit for the quarter dropped 17 percent to Rs 351 crore ($54 million), primarily due to the one-time tax adjustment. For the full year, the company reported a net profit of Rs 1,092 crore ($168 million) against revenue of Rs 31,980 crore ($4.92 billion).The firm is owned and controlled by Indian conglomerate Ruia-family of Mumbai. In the last week of August, Essar Group sold 98 percent of its stake in Essar Oil to a consortium led by Russian oil major Rosneft in a deal amounting to around Rs 82,697 crore ($12.9 billion).As part of the deal, oil major Rosneft will get a 49.13 percent stake in Essar Oil, while the Trafigura-UCP consortium will hold another 49.13 percent stake in the company. The remaining 1.74 percent will be held by retail shareholders.Essar has invested over Rs 5,200 crore ($800 million) since acquiring Stanlow in July 2011. The company currently has 39 petrol pumps in the UK currently and has permission to set up another 14. “Our long term target is to have 400 outlets in five years,” Sampath said. Prashant Ruia, Director, Essar Capital speaks during a news conference at the company’s headquarters in Mumbai, India August 21, 2017. REUTERS/Danish SiddiquiReuters”The major investment we have confirmed in Stanlow will materially increase throughput and further grow revenues, building on the tremendous progress we have made in turning around the business over the past six years,” said Prashant Ruia, non-executive chairman of Essar Oil UK.The firm has recently entered the direct aviation fuel supply market by selling the fuel produced at Stanlow to major airlines such as Emirates, Etihad, Jet2.com and Oman Air, ET reported.
Foreign minister AK Abdul Momen. File photoBangladesh has come up with a new proposal for India regarding the Rohingya crisis.The proposal states that a safe haven can be created in Myanmar’s Rakhine state where the driven-out Rohingyas can be rehabilitated.And countries who are friends of Myanmar can take responsibility of ensuring that the Rohingyas can live there free of fear, in safety, with a sustainable livelihood. These countries can include India, China and ASEAN members.Bangladesh’s foreign minister AK Abdul Momen placed this proposal before the Indian prime minister Narendra Modi and foreign minister Sushma Swaraj during his recent visit to India, adding that India should include this in talks with Myanmar.Abdul Momen was speaking to the media after a dinner hosted in his honour by the Bangladesh High Commission in Delhi on Friday.The foreign minister said, Myanmar may agree to its friendly states taking responsibility of overseeing the Rohingya and monitoring their welfare upon their return. He said Modi responded by saying it was an ‘innovative proposal.’Abdul Momen chose India for his first overseas visit after becoming foreign minister. During the three-day trip, he attended that Bangladesh-India Joint Consultant Commission (JCC) meeting.Speaking to the media, he said that he had also placed the proposal before Sushma Swaraj. She wanted to know if he had given the proposal to prime minister Modi and he assured her he had, albeit in brief.Sushma then asked that why he hadn’t proposed this to the Myanmar foreign minister who was his friend. He said that Myanmar would given the proposal more importance if it came from India.During the JCC meet, Abdul Momen stressed the need for sharing the waters of common rivers including Teesta. Some of these flow in from China. He said that the experts of the Bangladesh-India Joint Rivers Commission (JRC) would decide whether the issue of water sharing would be sorted out bilaterally or multilaterally.* This report, originally published in Prothom Alo print edition, has been rewritten in English by Ayesha Kabir
However, Mansuripur’s bold claim of a paradox with the Lorentz law has generated some intense criticism. One critic, Daniel Vanzella, a physics professor at the University of Sao Paulo in Sao Carlos, Brazil, has submitted a comment to Physical Review Letters arguing that the Lorentz law is perfectly compatible with special relativity, and that Mansuripur has misunderstood relativistic mechanics. The only paradox, Vanzella says, is why the high-ranking journal accepted the paper in the first place.Charge-magnet paradoxThe basis of Mansuripur’s argument is that the Lorentz law violates special relativity by producing different results in different reference frames. According to special relativity, the laws of physics – including electromagnetism – must be the same in all non-accelerating reference frames. He describes a scenario in which a magnetic dipole and a nearby electric charge are located a certain distance apart. When the magnet and the electric charge are at rest, no net force is exchanged between the two. This is because static electric charges only produce electric fields (to which the magnet is oblivious), and static magnets only produce magnetic fields (to which the static electric charge is oblivious). Both the Lorentz law and the Einstein-Laub version give the same result: the magnet experiences neither a force nor a torque from the electric charge.However, the Lorentz law gives a different result when a stationary observer watches the magnet and electric charge in a moving reference frame. Here, the observer sees the moving electric charge exert a torque on the moving magnet, causing the magnet to rotate as it tries to align itself with the electric field. The presence of this torque differs from the observation in the stationary reference frame where there is no torque.On the other hand, the Einstein-Laub formula, when combined with a corresponding torque formula, gives zero torque value for observers in both reference frames, complying with special relativity.The Lorentz law’s incompatibility with special relativity is not its only shortcoming, according to Mansuripur. Another equally important issue is the long-standing problem of “hidden momentum,” in which he shows that the Lorentz law fails to conserve momentum in certain situations involving magnetic media. In contrast, the Einstein-Laub equations show complete consistency with the conservation laws. For Mansuripur, this evidence indicates that the Einstein-Laub formula should be considered as a better way to understand classical electrodynamics. (Phys.org) — The laws of classical electromagnetism that were developed in the 19th century are the same laws that scientists use today. They include Maxwell’s four equations along with the Lorentz law, which describes the force exerted by electric and magnetic fields on charged particles. But Masud Mansuripur, a professor of Optical Sciences at The University of Arizona in Tucson, is now arguing that the Lorentz law of force is incompatible with special relativity and momentum conservation, and should be abandoned. In a recent issue of Physical Review Letters, he has suggested replacing the Lorentz law with a more general expression of electromagnetic force density, such as one developed by Albert Einstein and Jakob Laub in 1908. Best yet test of Lorentz invariance “This work provides a firm basis for all calculations of force, torque, momentum and angular momentum whenever electromagnetic fields (microwave, light, etc.) interact with material media,” Mansuripur told Phys.org. “The electromagnetic momentum and angular momentum become well-defined universal entities (i.e., the Abraham momentum), the need for ‘hidden momentum’ disappears, and satisfaction of conservation laws as well as conformity with special relativity are guaranteed.He explains that, during the past century, there has been a proliferation of equations for force and torque in the scientific literature, with scientists using several different formulas for the electromagnetic momentum. “My paper fixes the foundational equations and allows researchers to compare their experimental results against a single, well-defined theory,” he said.Quantum natureAccording to Mansuripur, the underlying reason for the difference between the Lorentz law and Einstein-Laub formula involves how each equation mathematically describes the quantum nature of electromagnetic fields and media. For its part, the Lorentz law depicts electric and magnetic dipoles as pairs of positive and negative charges or stable loops of current that interact with electromagnetic fields in terms of free and bound charges and currents. In contrast, the Einstein-Laub formula describes material media as spatio-temporal distributions of charge, current, polarization, and magnetization. Mansuripur explains why this distinction is important.“The fact that the electron orbits inside atoms and molecules are stable is a quantum-mechanical phenomenon,” he said. “Neither Maxwell’s equations nor the Lorentz law of force (and nor, for that matter, the Einstein-Laub force/torque equations) can account for the stability of the electron orbit. The fact that electrons, protons and neutrons have a magnetic moment associated with their spin angular momentum is also a relativistic quantum effect that has no explanation within classical physics. What Maxwell’s equations and the Lorentz law (or the Einstein-Laub law) do is provide formulas that describe the behavior of fields and material media as they are, without attempting to justify that behavior. The Lorentz law, however, simplifies the underlying physics by assuming that electric and magnetic dipoles can be treated as distributions of ordinary electrical charge and current. In contrast, the Einstein-Laub equation and the accompanying torque equation treat free charge, free current, electric dipoles, and magnetic dipoles as four distinct constituents of material media.“So, for example, the fact that a magnetic dipole is associated with something resembling a loop of current is a quantum mechanical effect. The Lorentz law does not ignore this fact, but it takes the resemblance to a current loop too far, treating the magnetic dipole as if it were actually a loop of ordinary current. In contrast, the Einstein-Laub formula acknowledges that magnetic dipoles exist as distinct entities – what makes them distinct is quantum mechanics, of course, but Einstein-Laub does not attempt to justify the existence of these dipoles or their nature. The Einstein-Laub formulas then provide a ‘recipe’ for calculating the force and torque on these dipoles, which turns out to be different from the ‘recipe’ provided by the Lorentz law.”No paradox?One critic of Mansuripur’s ideas, Vanzella, thinks that the paper is so flawed that it should not have been published at all. In his comment submitted to the journal, Vanzella points out that the Lorentz force can be put in a covariant form. In special relativity, a covariant law cannot lead to incompatible descriptions of the same phenomenon in different inertial reference frames. He explains that Mansuripur has incorrectly used relativistic mechanics and ignored a hidden momentum that makes the Lorentz formula predict a torque in one reference frame but not another. “This has blown way out of proportion,” Vanzella said. “Let me begin by stating the most important point: there is no incompatibility between the Lorentz force and special relativity. This is not a matter of opinion: any relativist knows that this is impossible for any specially-covariant law (as is the Lorentz force). By construction, a specially-covariant law is compatible with special relativity. This means that if it leads to a satisfactory description of a phenomenon in one inertial frame, then it leads to consistent descriptions in any inertial frame; there are no paradoxes.”He added that apparent paradoxes appear frequently when dealing with special relativity, but these paradoxes are actually due to simply missing or overlooking part of the relativistic argument. He says that a very similar “paradox” to the charge-magnet paradox, called the Trouton-Noble paradox, was presented and resolved more than 100 years ago. “In this particular case, using a current loop in a perfectly-conducting ring to model the magnet’s magnetic moment, one has to use special relativity to show that, even when the ring is at rest, the total momentum of the system is not zero (when subject to an external electric field),” he explained. “This momentum has been termed ‘hidden’ in the literature and this has led to some confusion, but let me stress that it is real momentum. Mansuripur is missing the point that this momentum is not an ad hoc invention only to solve paradoxes; its existence is forced upon us (upon Nature, actually) due to the principles of special relativity alone. In my comment I do not postulate the existence of this momentum. I simply use special relativity to calculate it; no additional hypothesis other than special relativity and the Lorentz force. Therefore, when Mansuripur dismisses this ‘hidden’ momentum he is doing exactly what I said is needed to arrive at a paradox: missing or overlooking part of the relativistic argument.”Despite his strong disagreement with Mansuripur, he emphasized that his criticism does not suggest anything against Mansuripur’s scientific credibility.“Please note that I don’t think that Mansuripur not knowing the solution of the ‘charge-magnet paradox’ (or not understanding the given solution) is that bad,” Vanzella said. “Special relativity is certainly not his expertise and confuses a lot of people, even physicists.”He also added that he’s not necessarily arguing that the Lorentz law must be the correct law of force, either, but just that special relativity cannot be used to testify against it. The question of which law is correct is an experimental issue. Still, he’s adamant that there is no paradox in this situation.“I wouldn’t even call Mansuripur’s idea ‘controversial,’” he said. “Would you call ‘controversial’ the idea that the Earth is flat? It is simply and provably wrong (I mean the claim that the Lorentz force is incompatible with special relativity).”In a response to Vanzella’s comment, also submitted to Physical Review Letters, Mansuripur has stuck to his original argument, explaining that there is no need to introduce hidden momentum, and that the Trouton-Noble paradox was subtly but significantly different than the charge-magnet paradox.Future of Einstein-LaubDespite the advantages of Einstein-Laub formula, Mansuripur acknowledges that it is not without its own problems. In 1979, physicist Iver Brevik performed an extensive review of the Einstein-Laub formula and other possible candidates for an energy-momentum tensor for the electromagnetic field. In some of the experiments, the Einstein-Laub formula did not match actual observations as closely as another formula, the Helmholtz force equation. However, Mansuripur argues that, due to the potential significance of this idea, the contrary evidence deserves a closer examination.“My colleagues and I are currently trying to identify situations where the distinction between the Lorentz law and the Einstein-Laub formulation is unambiguous, then try to conduct experiments to determine which law is operative in such situations,” he said. “Personally, I don’t attach much significance to the historical evidence against the Einstein-Laub formulation as reviewed in the paper by Brevik. The experiments were all electrostatic experiments, involving the flow of some dielectric fluid into a capacitor. The theoretical methods used to analyze the problem were extremely confusing; many approximations were made, and the Einstein-Laub formula itself was never used directly; instead they used a stress tensor associated with Einstein-Laub, which I have shown elsewhere to be incorrect.Mansuripur also plans to further investigate what he thinks has been a much overlooked distinction between the two formulas: a term that describes the force density of an electric field acting on the polarization density of a material medium. Whereas the Lorentz law uses –(del.P)E, the Einstein-Laub formula uses (P.del)E. Although the two formulations give exactly the same total force and total torque on any solid object, differences emerge when dealing with soft objects.“If applied to soft objects such as biological cells under intense illumination or droplets of oil or water in optical tweezers, the two formulas give different force and torque ‘distributions’ throughout the object,” he said. “This difference in force/torque distribution will then manifest itself in different deformations of the object under intense illumination. Our near-term goal, therefore, is to look for deformations of soft objects in optical tweezers experiments. A long-term goal is to look for observable differences between Lorentz and Einstein-Laub in magnetic materials.” This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Charge-magnet paradox: the point electric charge q and the point magnetic dipole to its right are separated by distance d in the x’y’z’ frame. An observer in the x’y’z’ frame sees no torque, but a stationary observer in the xyz frame watching the x’y’z’ system move with constant velocity along the z axis sees the moving electric charge exert a torque on the moving magnet. Image credit: Mansuripur. ©2012 American Physical Society More information: Masud Mansuripur, “Trouble with the Lorentz Law of Force: Incompatibility with Special Relativity and Momentum Conservation.” Physical Review Letters 108, 193901 (2012). DOI: 10.1103/PhysRevLett.108.193901 Explore further Copyright 2012 Phys.org All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. Citation: Is a classical electrodynamics law incompatible with special relativity? (2012, May 24) retrieved 18 August 2019 from https://phys.org/news/2012-05-classical-electrodynamics-law-incompatible-special.html Journal information: Physical Review Letters