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U.S. Presses Other Muslim Nations to Establish Ties With Israel – The New York Times

Middle East|U.S. Presses Other Muslim Nations to Establish Ties With Israel

Secretary of State Mike Pompeo visited Sudan and Bahrain, and an American delegation will accompany Israelis on the first direct commercial flight between Tel Aviv and Abu Dhabi.

Credit…Pool photo by Debbie Hill

Peter Baker

WASHINGTON — The Trump administration sought on Tuesday to test the waters to determine if it can persuade other Arab and Muslim countries to establish full diplomatic relations with Israel after a breakthrough agreement by the United Arab Emirates to open normal ties.

Secretary of State Mike Pompeo visited Sudan and Bahrain, two of the administration’s top prospects for bringing Israel together with more of its neighbors in a region where it has faced generations of hostility. But American officials cautioned that the situation remained fluid and no one should expect overnight agreements.

To maintain a sense of momentum, President Trump is sending a delegation to Israel next week to accompany high-level Israeli officials on the first direct commercial flight between Tel Aviv and Abu Dhabi, the capital of the United Arab Emirates, probably on an El Al carrier with its traditional Star of David on the tail. The delegations will seek to forge cooperation in the aviation, security, health and banking sectors, among others, in accordance with the agreement that the two nations announced two weeks ago.

“This is a historic agreement,” Prime Minister Benjamin Netanyahu of Israel said in a statement. “It will bring engines of growth. It can help bring about an economic flourishing in general and during the corona era in particular. I hope that other countries in our region will join the cycle of peace.”

Reflecting on the inaugural flight to the Emirates, scheduled for Monday, Mr. Netanyahu added: “I also hope that you, citizens of Israel, will also be able to visit Dubai and Abu Dhabi soon. There is much to see there.”

The American delegation will be led by Jared Kushner, the president’s son-in-law and senior adviser who has led efforts to forge peace in the Middle East, along with Robert C. O’Brien, the national security adviser; Avi Berkowitz, Mr. Trump’s Middle East envoy; and Brian Hook, the outgoing special envoy for Iran.

Officials did not comment on the route the plane would take, which involves diplomacy of its own. While El Al has regular service with Jordan, it would need to fly through airspace where it is normally not allowed, over either Iraq or Saudi Arabia. Iraq’s prime minister visited Mr. Trump at the White House last week, which may have cleared the way.

If fulfilled, the Aug. 13 agreement, called the Abraham Accord, would make the Emirates the third Arab nation along with Egypt and Jordan to have full diplomatic relations with Israel, including the exchange of embassies and ambassadors. The Emirates signed off on the deal after Israel agreed to suspend annexation of parts of the West Bank.

The White House hopes to enlist others to follow suit, with Sudan, Bahrain and Oman at the top of the list, in effect formalizing a growing Israeli-Arab alignment against Iran, even at the expense of the Palestinians, who complained about being abandoned.

Mr. Pompeo made a point on Tuesday of posting on Twitter a photograph of his airplane’s in-flight map during his flight from Tel Aviv to Omdurman in Sudan. “Happy to announce that we are on the FIRST official NONSTOP flight from Israel to Sudan!” he wrote.

From there, he flew to Bahrain, where he tweeted: “The Abraham Accords show that peace is achievable. Seizing the momentum is vital.”

But there are complicating factors. Sudan has been ruled by a transitional government since the fall of President Omar Hassan al-Bashir last year, and a spokesman was quoted telling news agencies that it “does not have a mandate” to “decide on normalization with Israel.”

Moreover, Sudan wants something from the United States — to be taken off the list of state sponsors of terrorism, a designation it has had since the 1990s when it sheltered Osama bin Laden — which would help reintegrate its struggling economy with that of the outside world.

Mr. Pompeo wants Sudan to compensate victims of the 1998 bombings of two American embassies in East Africa before it is removed from the list, while Sudan wants Congress to provide immunity against future lawsuits stemming from past terrorist incidents.

Lara Jakes contributed reporting from Washington, and David M. Halbfinger from Jerusalem.

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Gravity Other

Why Gravity Is Not Like the Other Forces – Quanta Magazine

Abstractions blog

We asked four physicists why gravity stands out among the forces of nature. We got four different answers.

A falling apple.

Physicists still ponder why, exactly, the apple falls.

Samuel Velasco/Quanta Magazine

Physicists have traced three of the four forces of nature — the electromagnetic force and the strong and weak nuclear forces — to their origins in quantum particles. But the fourth fundamental force, gravity, is different.

Our current framework for understanding gravity, devised a century ago by Albert Einstein, tells us that apples fall from trees and planets orbit stars because they move along curves in the space-time continuum. These curves are gravity. According to Einstein, gravity is a feature of the space-time medium; the other forces of nature play out on that stage.

But near the center of a black hole or in the first moments of the universe, Einstein’s equations break. Physicists need a truer picture of gravity to accurately describe these extremes. This truer theory must make the same predictions Einstein’s equations make everywhere else.

Physicists think that in this truer theory, gravity must have a quantum form, like the other forces of nature. Researchers have sought the quantum theory of gravity since the 1930s. They’ve found candidate ideas — notably string theory, which says gravity and all other phenomena arise from minuscule vibrating strings — but so far these possibilities remain conjectural and incompletely understood. A working quantum theory of gravity is perhaps the loftiest goal in physics today.

What is it that makes gravity unique? What’s different about the fourth force that prevents researchers from finding its underlying quantum description? We asked four different quantum gravity researchers. We got four different answers.

Gravity Breeds Singularities

Claudia de Rham, a theoretical physicist at Imperial College London, has worked on theories of massive gravity, which posit that the quantized units of gravity are massive particles:

Einstein’s general theory of relativity correctly describes the behavior of gravity over close to 30 orders of magnitude, from submillimeter scales all the way up to cosmological distances. No other force of nature has been described with such precision and over such a variety of scales. With such a level of impeccable agreement with experiments and observations, general relativity could seem to provide the ultimate description of gravity. Yet general relativity is remarkable in that it predicts its very own fall.

General relativity yields the predictions of black holes and the Big Bang at the origin of our universe. Yet the “singularities” in these places, mysterious points where the curvature of space-time seems to become infinite, act as flags that signal the breakdown of general relativity. As one approaches the singularity at the center of a black hole, or the Big Bang singularity, the predictions inferred from general relativity stop providing the correct answers. A more fundamental, underlying description of space and time ought to take over. If we uncover this new layer of physics, we may be able to achieve a new understanding of space and time themselves.

If gravity were any other force of nature, we could hope to probe it more deeply by engineering experiments capable of reaching ever-greater energies and smaller distances. But gravity is no ordinary force. Try to push it into unveiling its secrets past a certain point, and the experimental apparatus itself will collapse into a black hole.

Gravity Leads to Black Holes

Daniel Harlow, a quantum gravity theorist at the Massachusetts Institute of Technology, is known for applying quantum information theory to the study of gravity and black holes:

Black holes are the reason it’s difficult to combine gravity with quantum mechanics. Black holes can only be a consequence of gravity because gravity is the only force that is felt by all kinds of matter. If there were any type of particle that did not feel gravity, we could use that particle to send out a message from the inside of the black hole, so it wouldn’t actually be black.

The fact that all matter feels gravity introduces a constraint on the kinds of experiments that are possible: Whatever apparatus you construct, no matter what it’s made of, it can’t be too heavy, or it will necessarily gravitationally collapse into a black hole. This constraint is not relevant in everyday situations, but it becomes essential if you try to construct an experiment to measure the quantum mechanical properties of gravity.

Our understanding of the other forces of nature is built on the principle of locality, which says that the variables that describe what’s going on at each point in space — such as the strength of the electric field there — can all change independently. Moreover, these variables, which we call “degrees of freedom,” can only directly influence their immediate neighbors. Locality is important to the way we currently describe particles and their interactions because it preserves causal relationships: If the degrees of freedom here in Cambridge, Massachusetts, depended on the degrees of freedom in San Francisco, we may be able to use this dependence to achieve instantaneous communication between the two cities or even to send information backward in time, leading to possible violations of causality.

The hypothesis of locality has been tested very well in ordinary settings, and it may seem natural to assume that it extends to the very short distances that are relevant for quantum gravity (these distances are small because gravity is so much weaker than the other forces). To confirm that locality persists at those distance scales, we need to build an apparatus capable of testing the independence of degrees of freedom separated by such small distances. A simple calculation shows, however, that an apparatus that’s heavy enough to avoid large quantum fluctuations in its position, which would ruin the experiment, will also necessarily be heavy enough to collapse into a black hole! Therefore, experiments confirming locality at this scale are not possible. And quantum gravity therefore has no need to respect locality at such length scales.

Indeed, our understanding of black holes so far suggests that any theory of quantum gravity should have substantially fewer degrees of freedom than we would expect based on experience with the other forces. This idea is codified in the “holographic principle,” which says, roughly speaking, that the number of degrees of freedom in a spatial region is proportional to its surface area instead of its volume.

Gravity Creates Something From Nothing

Juan Maldacena, a quantum gravity theorist at the Institute for Advanced Study in Princeton, New Jersey, is best known for discovering a hologram-like relationship between gravity and quantum mechanics:

Particles can display many interesting and surprising phenomena. We can have spontaneous particle creation, entanglement between the states of particles that are far apart, and particles in a superposition of existence in multiple locations.

In quantum gravity, space-time itself behaves in novel ways. Instead of the creation of particles, we have the creation of universes. Entanglement is thought to create connections between distant regions of space-time. We have superpositions of universes with different space-time geometries.

Furthermore, from the perspective of particle physics, the vacuum of space is a complex object. We can picture many entities called fields superimposed on top of one another and extending throughout space. The value of each field is constantly fluctuating at short distances. Out of these fluctuating fields and their interactions, the vacuum state emerges. Particles are disturbances in this vacuum state. We can picture them as small defects in the structure of the vacuum.


When we consider gravity, we find that the expansion of the universe appears to produce more of this vacuum stuff out of nothing. When space-time is created, it just happens to be in the state that corresponds to the vacuum without any defects. How the vacuum appears in precisely the right arrangement is one of the main questions we need to answer to obtain a consistent quantum description of black holes and cosmology. In both of these cases there is a kind of stretching of space-time that results in the creation of more of the vacuum substance.

Gravity Can’t Be Calculated

Sera Cremonini, a theoretical physicist at Lehigh University, works on string theory, quantum gravity and cosmology:

There are many reasons why gravity is special. Let me focus on one aspect, the idea that the quantum version of Einstein’s general relativity is “nonrenormalizable.” This has implications for the behavior of gravity at high energies.

In quantum theories, infinite terms appear when you try to calculate how very energetic particles scatter off each other and interact. In theories that are renormalizable — which include the theories describing all the forces of nature other than gravity — we can remove these infinities in a rigorous way by appropriately adding other quantities that effectively cancel them, so-called counterterms. This renormalization process leads to physically sensible answers that agree with experiments to a very high degree of accuracy.

The problem with a quantum version of general relativity is that the calculations that would describe interactions of very energetic gravitons — the quantized units of gravity — would have infinitely many infinite terms. You would need to add infinitely many counterterms in a never-ending process. Renormalization would fail. Because of this, a quantum version of Einstein’s general relativity is not a good description of gravity at very high energies. It must be missing some of gravity’s key features and ingredients.

However, we can still have a perfectly good approximate description of gravity at lower energies using the standard quantum techniques that work for the other interactions in nature. The crucial point is that this approximate description of gravity will break down at some energy scale — or equivalently, below some length.

Above this energy scale, or below the associated length scale, we expect to find new degrees of freedom and new symmetries. To capture these features accurately we need a new theoretical framework. This is precisely where string theory or some suitable generalization comes in: According to string theory, at very short distances, we would see that gravitons and other particles are extended objects, called strings. Studying this possibility can teach us valuable lessons about the quantum behavior of gravity.

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Estrogen Other

Can Estrogen and Other Sex Hormones Help Men Survive Covid-19? – The New York Times

Men are more likely than women to die of the coronavirus, so scientists are treating them with something women have more of: female sex hormones.

Credit…Jake Michaels for The New York Times

Roni Caryn Rabin

As the novel coronavirus swept through communities around the world, preying disproportionately on the poor and the vulnerable, one disadvantaged group has demonstrated a remarkable resistance. Women, whether from China, Italy or the U.S., have been less likely to become acutely ill — and far more likely to survive.

Which has made doctors wonder: Could hormones produced in greater quantities by women be at work?

Now scientists on two coasts, acting quickly on their hunches in an effort to save men’s lives, are testing the hypothesis. The two clinical trials will each dose men with the sex hormones for limited durations.

Last week, doctors on Long Island in New York started treating Covid-19 patients with estrogen in an effort to increase their immune systems, and next week, physicians in Los Angeles will start treating male patients with another hormone that is predominantly found in women, progesterone, which has anti-inflammatory properties and can potentially prevent harmful overreactions of the immune system.

“There’s a striking difference between the number of men and women in the intensive care unit, and men are clearly doing worse,” said Dr. Sara Ghandehari, a pulmonologist and intensive care physician at Cedars-Sinai in Los Angeles who is the principal investigator for the progesterone study. She said 75 percent of the hospital’s intensive care patients and those on ventilators are men.

And pregnant women, who are usually immunocompromised but have high levels of estrogen and progesterone, tend to have mild courses of the disease. “So something about being a woman is protective, and something about pregnancy is protective, and that makes us think about hormones,” Dr. Ghandehari said.

Some experts who study sex differences in immunity, however, warned that hormones may fail to be the magic bullet that some are hoping for; even elderly women with Covid-19 are outliving their male peers, and there is a drastic reduction in levels of hormones for women after menopause.

The genesis of the estrogen trial at the Renaissance School of Medicine at Stony Brook University on Long Island stemmed from a similar observation, said Dr. Sharon Nachman, the trial’s principal investigator, who credited a Stony Brook surgeon, Dr. Antonios Gasparis, with the idea.

The trial enrolled its first patient this past week, and preliminary results could be available in a few months, she said.

“It’s totally out of the box, which is how good ideas often start,” said Dr. Nachman, associate dean for research at the Renaissance School, which is part of the State University of New York.

The gender gap in coronavirus survival became apparent early in the pandemic. Reports from China indicated men were dying at higher rates, but the disparity was attributed to higher smoking rates. But the outcomes were consistent in other countries, with men in Italy dying at higher rates than women, and men in New York City dying at nearly double the rate of women.

Scientists who study sex differences say that both biological differences in immunity, as well as behavioral factors are at play. Men smoke more almost everywhere, they say; men also wash their hands less. While women appear to have more robust immune systems, these experts say, the causes are complex and multifactorial, and hormones are only part of the picture.

If such sex hormones were the primary protective factor for women, then elderly women with Covid-19 would fare as poorly as elderly men, because women’s reproductive hormones plummet after menopause, said Sabra Klein, a scientist who studies sex differences in viral infections and vaccination responses at the Johns Hopkins Bloomberg School of Public Health.

But that’s not the case, she said.

“We see this bias across the life course,” Dr. Klein said. “Older men are still disproportionately affected, and that suggests to me it’s got to be something genetic, or something else, that’s not just hormonal.”

“Estrogen has immune modulatory properties — don’t get me wrong,” she continued. “You could get a beneficial effect in both men and women. But if women are better at recovery at 93 years old, I doubt it’s hormones.”

Research has shown estrogen may have an effect on a protein known as angiotensin-converting enzyme 2 (ACE2), for example. The coronavirus uses ACE2 receptors on the surfaces of cells as an entry route, and ACE2 is regulated differently in men and women, said Kathryn Sandberg, director of the Center for the Study of Sex Differences in Health, Aging and Disease at Georgetown University.

In studies with rats, Dr. Sandberg and her colleagues have shown that estrogen can reduce ACE2 protein expression in their kidneys, so it is possible the hormone may reduce ACE2 expression in men as well.

Dr. Nachman said, “We may not understand exactly how estrogen works, but maybe we can see how the patient does,” adding that estrogen played a complex role, both in the early immune response that could help clear a viral infection, as well as in a secondary clean up or repair response, which could evolve into a cytokine storm.

“While we see women do get infected, their responses are different,” Dr. Nachman said. “We see fewer of them having the second, disregulated immune response.”

The Stony Brook estrogen trial is recruiting 110 patients who come to the hospital’s emergency room with symptoms like fever, cough, shortness of breath or pneumonia, and who have either tested positive for Covid-19 or are presumed to have the illness, as long as they do not require intubation.

The trial is open to adult men as well as to women aged 55 and older, since they have low levels of estrogen. Half of the participants will be given an estradiol patch for one week, while the other half will serve as a control group, and researchers will follow them to see whether estrogen reduces the severity of their disease.

The Cedars-Sinai study is smaller, with only 40 subjects, all men, half of whom will be a control group. Only hospital inpatients with mild to moderate disease who have tested positive for Covid-19 can participate. (Patients with certain conditions, like a history of blood clots, are excluded for safety reasons.)

The patients will get two shots of progesterone a day for five days.

They will be monitored to see if their status is improving, how their needs for oxygen change and whether they go on to require intensive care or mechanical ventilation; their progress will be compared to patients in the control group.

The researchers in Los Angeles are pinning their hopes on progesterone rather than estrogen because research has shown that the hormone reduces pro-inflammatory immune cells, and supports those that fight inflammation, Dr. Ghandehari said. The hypothesis is that progesterone will prevent or dampen a harmful overreaction of the immune system, called a cytokine storm, and will reduce the likelihood of acute respiratory distress syndrome.

Both hormones are believed to be safe, especially when used for short durations. Participants will be warned of possible side effects that may be a first for many men, like tenderness in the breast and hot flashes.

  • Updated April 11, 2020

    • When will this end?

      This is a difficult question, because a lot depends on how well the virus is contained. A better question might be: “How will we know when to reopen the country?” In an American Enterprise Institute report, Scott Gottlieb, Caitlin Rivers, Mark B. McClellan, Lauren Silvis and Crystal Watson staked out four goal posts for recovery: Hospitals in the state must be able to safely treat all patients requiring hospitalization, without resorting to crisis standards of care; the state needs to be able to at least test everyone who has symptoms; the state is able to conduct monitoring of confirmed cases and contacts; and there must be a sustained reduction in cases for at least 14 days.

    • What should I do if I feel sick?

      If you’ve been exposed to the coronavirus or think you have, and have a fever or symptoms like a cough or difficulty breathing, call a doctor. They should give you advice on whether you should be tested, how to get tested, and how to seek medical treatment without potentially infecting or exposing others.

    • Should I wear a mask?

      The C.D.C. has recommended that all Americans wear cloth masks if they go out in public. This is a shift in federal guidance reflecting new concerns that the coronavirus is being spread by infected people who have no symptoms. Until now, the C.D.C., like the W.H.O., has advised that ordinary people don’t need to wear masks unless they are sick and coughing. Part of the reason was to preserve medical-grade masks for health care workers who desperately need them at a time when they are in continuously short supply. Masks don’t replace hand washing and social distancing.

    • How does coronavirus spread?

      It seems to spread very easily from person to person, especially in homes, hospitals and other confined spaces. The pathogen can be carried on tiny respiratory droplets that fall as they are coughed or sneezed out. It may also be transmitted when we touch a contaminated surface and then touch our face.

    • Is there a vaccine yet?

      No. Clinical trials are underway in the United States, China and Europe. But American officials and pharmaceutical executives have said that a vaccine remains at least 12 to 18 months away.

    • What makes this outbreak so different?

      Unlike the flu, there is no known treatment or vaccine, and little is known about this particular virus so far. It seems to be more lethal than the flu, but the numbers are still uncertain. And it hits the elderly and those with underlying conditions — not just those with respiratory diseases — particularly hard.

    • What if somebody in my family gets sick?

      If the family member doesn’t need hospitalization and can be cared for at home, you should help him or her with basic needs and monitor the symptoms, while also keeping as much distance as possible, according to guidelines issued by the C.D.C. If there’s space, the sick family member should stay in a separate room and use a separate bathroom. If masks are available, both the sick person and the caregiver should wear them when the caregiver enters the room. Make sure not to share any dishes or other household items and to regularly clean surfaces like counters, doorknobs, toilets and tables. Don’t forget to wash your hands frequently.

    • Should I stock up on groceries?

      Plan two weeks of meals if possible. But people should not hoard food or supplies. Despite the empty shelves, the supply chain remains strong. And remember to wipe the handle of the grocery cart with a disinfecting wipe and wash your hands as soon as you get home.

    • Should I pull my money from the markets?

      That’s not a good idea. Even if you’re retired, having a balanced portfolio of stocks and bonds so that your money keeps up with inflation, or even grows, makes sense. But retirees may want to think about having enough cash set aside for a year’s worth of living expenses and big payments needed over the next five years.


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