Wednesday 11 November 2020

Hawking’s 50-Year Mystery About Falling into Black Holes Has Finally Been Solved

 By Andy Corbley - Nov 10, 2020

 www.goodnewsnetwork.org

 

 If you lurch into the event horizon of a black hole, will you ever come out? According to a series of new calculations which just solved a 50-year old problem even Stephen Hawking couldn’t figure out, the answer is yes.

 

 

 

It’s being described as a landmark calculation—the biggest thing to happen in the field since the work of the famous British physicist established the problem in the first place.

Since the 1970s, physicists have been grappling with a logical contradiction in calculations surrounding a black hole called the “black hole information paradox.”

Hawking would use his “semiclassical” quantum/general-relativity hybrid-explanation of the physics of a black hole to describe what happens to matter in and around it.

He discovered that quantum uncertainty causes small amounts of radiation to emanate from a black hole called “Hawking radiation.” This eventually causes it to lose mass and evaporate into nothingness. If the black hole loses mass and eventually disappears, then what falls in must appear again somewhere. The question is: where/how/why does the information escape?

The authors of the new calculations, including scientists from UC Santa Barbara, have uncovered additional effects permitted by general relativity but that Hawking didn’t include, which describe a strange situation in which information that falls into a black hole will eventually come out, and that this phenomenon happens at the same time, and is partially to blame for the evaporation of a black hole.

Quantum entanglement

The way in which it works is through quantum entanglement, a phenomenon which simply means that particles of matter can be linked on the quantum level, and display patterns and reactivity to each other even though they could be separated by thousands of miles.

Don Page, a physicist at the University of Alberta, was a graduate student whose studies of black holes were key in helping his advisor, Stephen Hawking, make his realization that black holes emit radiation. In 1980, Page broke with Hawking and argued that information must be released or preserved in black holes, causing a schism among physicists at the time.

Page would go on to establish a timeline of a black hole’s lifespan—shaped like an upside-down V known as “Page time” or the “Page curve”—it described how information which fell into the black hole would escape through emitted Hawking radiation until the black hole was no more. This was called “entanglement entropy,” and set up physicists for a 30-year lay up to make a slam dunk calculation.

The V-shaped decline

“Over the past two years, physicists have shown that the entanglement entropy of black holes really does follow the Page curve, indicating that information gets out,” explains George Musser writing for Quanta Magazine.

The slam dunk was started in October 2018 by Ahmed Almheiri at the Institute for Advanced Study when he used quantum computing to create a universe in which a simple black hole system located at the center of space began emitting radiation as per Hawking’s theory.

The system begins to radiate as one entangled particle enters and another one leaves. This process continues, and the number of entangled particles increases, increasing the level of entanglement entropy.

If one imagines the black hole as the contents of a snow globe, and the glass of the globe as the event horizon (the edge of the black hole where the laws of physics begin to break down), Almheiri found that as the entangled entropy grew within the system, a “quantum extremal surface,” formed on the glass of the snow globe, just inside the event horizon.

Everything inside the quantum extremal surface is not part of the black hole, but rather like a collection of entangled particles which no longer contribute to the entropy in the system. Furthermore, the innermost particles in the simulated black hole became likewise detached from the black hole, forming something which Almheiri called “the island.”

At this point, non-entangled radiation begins to be emitted, and the black hole breathes itself out of existence.

On to the next one

In demonstrating that entanglement entropy of black holes followed the Page curve, Almheiri and his friends confirmed that black holes do in fact release information, though it comes out in such disorder as to appear like an encrypted password.

By now if one’s brain is still working after all this, Almheiri’s research amazingly includes theoretical tools that would allow researchers to “decrypt” the scrambled entangled particles in the quantum extremal surface, and figure out what they are and where they came from.

Last year, having just solved a 50-year puzzle and proved Page’s life’s work, the team decided to focus on the mysterious “island” of particles that were in—but not “of” the black hole. The island is part of the radiation, but haven’t flown out or been transferred to the extremal surface.

 This disconnect is theorized as being part of the reason why black holes go down the other side of the Page curve, and if solving the black hole information paradox seemed hard, Musser described the issue of the mysterious island as causing the team to “look off into the distance, momentarily lost for words.”

 

Monday 9 November 2020

Biden wins – experts on what it means for race relations, US foreign policy and the Supreme Court

 Biden wins – experts on what it means for race relations, US foreign policy and the Supreme Court

The American public has had its say and for the first time in a generation denied a sitting president a second term.

President Donald Trump’s tenure lasted just four years, but in that time he dragged policy on an array of key issues in a dramatic new direction.

Joe Biden’s victory, confirmed by the Associated Press late morning on Nov. 7, presents an opportunity to reset the White House agenda and put it on a different course.

Three scholars discuss what a Biden presidency may have in store in three key areas: race, the Supreme Court and foreign policy.

Racism, policing and Black Lives Matter protests

Brian Purnell, Bowdoin College

The next four years under a Biden administration will likely see improvements in racial justice. But to many, it will be a low bar to clear: President Donald Trump downplayed racist violenceegged on right-wing extremists and described Black Lives Matter as a “symbol of hate” during his four-year tenure.

Indeed, according to polls, most Americans agree that race relations have deteriorated under Trump.

Still, Biden is in some ways an unlikely president to advance a progressive racial agenda. In the 1970s, he opposed busing plans and stymied school desegregation efforts in Delaware, his home state. And in the mid-1990s he championed a federal crime bill that made incarceration rates for Black people worse. He bungled the hearings that brought Clarence Thomas to the Supreme Court by allowing Republican senators to dismiss Anita Hill’s damning testimony of Thomas’ sexual harassment and by failing to allow other Black women to testify.

But that was then.

During the 2020 campaign, President-elect Biden consistently spoke about problems stemming from systemic racism. Many voters will be hoping that his actions over the next four years must match his campaign words.

One area that the Biden administration will surely address is policing and racial justice. The Justice Department can bring accountability to police reform by returning to practices the Obama administration put in place to monitor and reform police departments, such as the use of consent degrees. More difficult reforms require redressing how mass incarceration caused widespread voter disenfranchisement in Black American and Latino communities.

“My administration will incentivize states to automatically restore voting rights for individuals convicted of felonies once they have served their sentences,” Biden told The Washington Post.

The killing of George Floyd earlier this year reinvigorated talk of addressing systemic racial discrimination through fundamental changes in how police departments hold officers accountable for misconduct and excessive force. It is unclear how far President-elect Biden will walk down this road. But evoking the words of the late civil rights icon and Congressman John Lewis, he at least suggested at the Democratic National Convention that America was ready to do the hard work of “rooting out systemic racism.”

Biden can help address how Americans think about and deal with unexamined racial biases through reversing the previous administration’s executive order banning anti-racism training and workshops. In so doing, Biden can build on psychological research on bias to make American workplaces, schools and government agencies equitable, just places.

Making progress fighting systemic racism will be a slow, uphill battle. A more immediate benefit to communities of color could come through Biden’s COVID-19 pandemic response – the Trump administration’s failure to stanch the spread of the coronavirus has led to deaths and economic consequences that have disproportionately fallen on racial and ethnic minorities.

On matters of race relations in the U.S., most Americans would agree that the era of Trump saw the picture worsen. The good news for Biden as president is there is nowhere to go but up.

The Supreme Court

Morgan Marietta, University of Massachusetts Lowell

Despite the fact that American voters have given Democrats control of the presidency, the conservative Supreme Court will continue to rule on the nature and extent of constitutional rights.

These liberties are considered by the court to be “beyond the reach of majorities,” meaning they are intended to be immune from the changing beliefs of the electorate.

However, appointees of Democrats and Republicans tend to have very different views on which rights the Constitution protects and which are left to majority rule.

The dominant judicial philosophy of the conservative majority – originalism – sees rights as powerful but limited. The protection of rights recognized explicitly by the Constitution, such as the freedoms of religion, speech and press and the freedom to bear arms, will likely grow stronger over the next four years. But the protection of expansive rights that the court has found in the phrase “due process of law” in the 14th Amendment, including privacy or reproductive rights, may well contract.

The Biden administration will probably not agree with the court’s future rulings on voting rights, gay rights, religious rights or the rights of noncitizens. Ditto for any rulings on abortion, guns, the death penalty and immigration. But there is little President-elect Biden can do to control the independent judiciary.

Unhappy with what a strong conservative majority on the court may do – including possibly overturning the Affordable Care Act – many Democrats have advocated radical approaches to altering what the court looks like and how it operates, though Biden himself has not stated a clear position.

Suggested options include term limitsadding a retirement agestripping the jurisdiction of the court for specific federal legislation, or increasing the size of the court. This strategy is known historically as court packing.

Ruth Bader Ginsburg opposed expanding the court, telling NPR in 2019 that “if anything would make the court look partisan, it would be … one side saying, ‘When we’re in power, we’re going to enlarge the number of judges, so we would have more people who would vote the way we want them to.’”

The Constitution does not establish the number of justices on the court, instead leaving that to Congress. The number has been set at nine since the 1800s, but Congress could pass a law expanding the number of justices to 11 or 13, creating two or four new seats.

However, this requires agreement by both houses of Congress.

The GOP seems likely to maintain a narrow control of the Senate. A 50/50 split is possible, but that won’t be clear until January when Georgia holds two runoff elections. Any of the proposed reforms of the court will be difficult, if not impossible, to pass under a divided Congress.

This leaves the Biden administration hoping for retirements that would gradually shift the ideological balance of the court.

One of the most likely may be Justice Clarence Thomas, who is 72 and the longest-serving member of the current court. Samuel Alito is 70 and Chief Justice John Roberts is 65. In other professions, that may sound like people soon to retire, but at the Supreme Court that is less likely. With the other three conservative justices in their 40s or 50s, the Biden administration may be fully at odds with the court for some time to come.

Foreign policy and defense

Neta Crawford, Boston University

President-elect Biden has signaled he will do three things to reset the U.S.‘s foreign policy.

First, Biden will change the tone of U.S. foreign relations. The Democratic Party platform called its section on military foreign policy “renewing American leadership” and emphasized diplomacy as a “tool of first resort.”

Biden seems to sincerely believe in diplomacy and is intent on repairing relations with U.S. allies that have been damaged over the last four years. Conversely, while Trump was, some say, too friendly with Russian President Vladimir Putin, calling him a “terrific person,” Biden will likely take a harder line with Russia, at least rhetorically.

This change in tone will also likely include rejoining some of the treaties and international agreements that the United States abandoned under the Trump administration. The most important of these include the Paris Climate Agreement, which the U.S. officially withdrew from on Nov. 4, and restoring funding to the United Nation’s Intergovernmental Panel on Climate Change.

If the U.S. is to extend the New START nuclear weapons treaty, the arms control deal with Russia due to expire in February, the incoming Biden administration would likely have to work with the outgoing administration on an extension. Biden has also signaled a willingness to rejoin the Iran nuclear deal jettisoned by Trump, if and when the Iranians return to the limits on nuclear infrastructure imposed by the agreement.

Second, in contrast to the large increases in military spending under Trump, President-elect Biden may make modest cuts in the U.S. military budget. Although he has said that cuts are not “inevitable” under his presidency, Biden has hinted at a smaller military presence overseas and is likely to change some priorities at the Pentagon by, for instance, emphasizing high-tech weapons. If the Senate – which must ratify any treaties – flips to Democrats’ control, the Biden administration may take more ambitious steps in nuclear arms control by pursuing deeper cuts with Russia and ratifying the Comprehensive Test Ban Treaty.

Third, the Biden administration will likely continue some Bush, Obama and Trump foreign policy priorities. Specifically, while a Biden administration will seek to end the war in Afghanistan, the administration will keep a focus on defeating the Islamic State and al-Qaida. Biden has said that he would reduce the current 5,200 U.S. forces in Afghanistan to 1,500-2,000 troops operating in the region in a counterterrorism role. The Biden administration is likely to continue the massive nuclear weapons modernization and air and naval equipment modernization programs begun under the Obama administration and accelerated and expanded under Trump, if only because they are popular with members of Congress who see the jobs they provide in their states.

And like the Bush, Obama and Trump administrations, the Biden administration will prioritize the economic and military threats it believes are posed by China. But, consistent with its emphasis on diplomacy, the Biden administration will likely also work more to constrain China through diplomatic engagement and by working with U.S. allies in the region.

https://theconversation.com/biden-wins-experts-on-what-it-means-for-race-relations-us-foreign-policy-and-the-supreme-court-149327

South Africa: Farm attack, elderly couple hospitalised after severe assault, Howick

 

South Africa: Farm attack, elderly couple hospitalised after severe assault, Howick





A farm attack took place in the early hours of 7 November 2020, at Karkloof farm, in Howick, in the KwaZulu Natal province of South Africa. An elderly couple were savagely assaulted by a solitary attacker with a rake. Wendy Wilson (84) suffered severe head injuries and lacerations, and also a loss of blood, and was taken to St Anne’s hospital.

Mrs Wilson who already suffers with bad arthritis and Parkinson’s and is very frail, was admitted to theater for urgent medical intervention and her husband, Archer Wilson (82) was admitted to casualty for stitches.

The attacker demanded money from them and when they said there was none, he beat them with the rake, Mrs Wilson taking the brunt of the blows.

Fortunately one of the old couple’s sons lives in a cottage on the smallholding, and heard his father’s calls for help and rushed to their aid causing the attacker to flee.

All roleplayers responded and assisted the elderly couple but there have been no arrests. There is no other information available at this stage.

Information supplied by Oorgrens veiligheid

South Africa Today – South Africa News

https://southafricatoday.net/south-africa-news/kwazulu-natal/farm-attack-elderly-couple-hospitalised-after-severe-assault-howick/

Sunday 8 November 2020

Arroz Palabok

 panlasangpinoy.com

 Arroz Palabok is a lugaw version of pancit palabok. It has the same great taste even if presented in a different form. Through this recipe, you can now make your own palabok lugaw in the comfort of your home.

 arroz palabok

Making arroz palabok is as easy as cooking arroz caldo. The toppings should be prepared beforehand. This means making toasted garlic and annato oil ahead of time. The congee itself is simple and straightforward to make.

Start by toasting the garlic topping by slowly frying in oil until it turns brown and crispy. Crushed garlic should be used for this purpose. Once done, separate the toasted garlic from the oil. Save the oil for later use.

Make annatto oil next. The oil gives this dish its reddish color. Simply combine oil and annatto seeds together and start to apply heat. I usually set it to low and wait until the oil starts to bubble. Once it happens, gently stir the seeds  and continue cooking until the oil turns orangey. It should take less than 2 minutes from the time you see the bubble. Separate the seeds from the oil once done.

The next ingredient that I pre-cook is the shrimp. It is literally topped over the congee once done. Make sure to completely cook it by boiling. I do this by boiling around 2 cups water. Once it rapidly boils, I add the shrimp and boil it for 35 seconds. Make sure to not overcook it. Separate the shrimp from the water and set it aside. Save the water, it is needed in the recipe.

Now that the toppings are prepared, cook the congee (lugaw) by sautéing onion and garlic. Add rice and stir. The next step is to pour the water used in boiling the shrimp. I also add 2 cups more water.  Let the mixture boil and then add a piece of Knorr Shrimp Cube. This will provide flavor to the dish. Sometimes, I also add a piece of Knorr Pork Cube along with the Shrimp Cube for that nice mixed flavor of pork and seafood. It is up to you, but I am telling you that it is good. Also add tinapa flakes at this point.

Continue cooking between low to medium heat while stirring constantly until the texture starts to get mushy. Don’t forget to add more water if needed. Season with fish sauce and ground white pepper.

arroz palabok recipe

Finish the dish by placing a serving on a bowl and then swirl some annatto oil over it. Top with crushed chicharon, chopped green onions, boiled shrimp, and toasted garlic. Serve this with calamansi.

Arroz Palabok

Palabok congee topped with shrimp, boiled egg, and toasted garlic.
 CourseCongee
 CuisineFilipino
 Prep Time5 minutes
 Cook Time1 hour
 Servings people
 Calories344kcal
 AuthorVanjo Merano

Ingredients

  • 1 cup rice washed
  • 1 piece Knorr Shrimp Cube
  • 10 pieces shrimp
  • 1 cup chicharon
  • 4 pieces eggs
  • 1/4 cup tinapa flakes
  • 1 piece onion minced
  • 4 cloves garlic minced
  • 1/4 cup toasted garlic
  • 1/4 cup annatto oil
  • 4 cups water
  • Patis and ground white pepper to taste