Tag: professor of physics (page 1 of 2)

High-Energy Cosmic Neutrinos Observed At The Geographic South Pole

An team of international experts has announced a new observation of high-energy neutrino particles using an instrument funded by the National Science Foundation (NSF). The particles from beyond our galaxy have been detected at the geographic South Pole, using a massive instrument buried deep in ice.The scientists from the IceCube Collaboration, a research team with headquarters at the Wisconsin IceCube Particle Astrophysics Center at the University of Wisconsin-Madison, pub [...]

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Mysterious Glow Detected At Center Of Milky Way Galaxy

In this image, the magenta color indicates the mysterious glow detected by NASA's NuSTAR space telescope.Excerpt from huffingtonpost.com A mysterious glow has been observed at the center of the Milky Way, and scientists are struggling to figure o...

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Quantum Entanglement Verified: Why Space Is Just The Construct That Gives The Illusion Of Separate Objects

“Space is just the construct that gives the illusion that there are separate objects” – Dr. Quantum (see video below)There is a phenomenon so strange, so fascinating, and so counter to what we believe to be the known scientific laws of the universe, that Einstein himself could not wrap his head around it. It’s called “quantum entanglement,” though Einstein referred to it as “spooky action at a distance.”An [...]

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Physicists: Black holes don’t erase information




Excerpt from earthsky.org
Since 1975, when Hawking showed that black holes evaporate from our universe, physicists have tried to explain what happens to a black hole’s information.

What happens to the information that goes into a black hole? Is it irretrievably lost? Does it gradually or suddenly leak out? Is it stored somehow? Physicists have puzzled for decades over what they call the information loss paradox in black holes. A new study by physicists at University at Buffalo – published in March, 2015 in the journal in Physical Review Letters – shows that information going into a black hole is not lost at all.

Instead, these researchers say, it’s possible for an observer standing outside of a black hole to recover information about what lies within.

Dejan Stojkovic, associate professor of physics at the University at Buffalo, did the research with his student Anshul Saini as co-author. Stojkovic said in a statement:
According to our work, information isn’t lost once it enters a black hole. It doesn’t just disappear.
What sort of information are we talking about? In principle, any information drawn into a black hole has an unknown future, according to modern physics. That information could include, for example, the characteristics of the object that formed the black hole to begin with, and characteristics of all matter and energy drawn inside.

Stojkovic says his research “marks a significant step” toward solving the information loss paradox, a problem that has plagued physics for almost 40 years, since Stephen Hawking first proposed that black holes could radiate energy and evaporate over time, disappearing from the universe and taking their information with them. 

Disappearing information is a problem for physicists because it’s a violation of quantum mechanics, which states that information must be conserved.
According to modern physics, any information about an astronaut entering a black hole - for example, height, weight, hair color - may be lost.  Likewise, information about he object that formed the hole, or any matter and energy entering the hole, may be lost.  This notion violates quantum mechanics, which is why it's known as the 'black hole information paradox.


According to modern physics, any information related to an astronaut entering a black hole – for example, height, weight, hair color – may be lost. This notion is known as the ‘information loss paradox’ of black holes because it violates quantum mechanics. Artist’s concept via Nature.

Stojkovic says that physicists – even those who believed information was not lost in black holes – have struggled to show mathematically how the information is preserved. He says his new paper presents explicit calculations demonstrating how it can be preserved. His statement from University at Buffalo explained:
In the 1970s, [Stephen] Hawking proposed that black holes were capable of radiating particles, and that the energy lost through this process would cause the black holes to shrink and eventually disappear. Hawking further concluded that the particles emitted by a black hole would provide no clues about what lay inside, meaning that any information held within a black hole would be completely lost once the entity evaporated.

Though Hawking later said he was wrong and that information could escape from black holes, the subject of whether and how it’s possible to recover information from a black hole has remained a topic of debate.

Stojkovic and Saini’s new paper helps to clarify the story.
Instead of looking only at the particles a black hole emits, the study also takes into account the subtle interactions between the particles. By doing so, the research finds that it is possible for an observer standing outside of a black hole to recover information about what lies within.
Interactions between particles can range from gravitational attraction to the exchange of mediators like photons between particles. Such “correlations” have long been known to exist, but many scientists discounted them as unimportant in the past.
Stojkovic added:
These correlations were often ignored in related calculations since they were thought to be small and not capable of making a significant difference.
Our explicit calculations show that though the correlations start off very small, they grow in time and become large enough to change the outcome.
Artist's impression of a black hole, via Icarus
Artist’s impression of a black hole, via Icarus

Bottom line: Since 1975, when Stephen Hawking and Jacob Bekenstein showed that black holes should slowly radiate away energy and ultimately disappear from the universe, physicists have tried to explain what happens to information inside a black hole. Dejan Stojkovic and Anshul Saini, both of University at Buffalo, just published a new study that contains specific calculations showing that information within a black hole is not lost.

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Frustrated magnets showing features of Hall Effect stun Princeton University researchers


Frustrated-Magnets



Excerpt from worldtechtoday.com

A group of researchers at the Princeton University has found that frustrated magnets, inspite of not possessing any magnetic feature at low temperatures, do exhibit features of Hall Effect. ‘Frustrated’ magnets are so called because of their inability of getting a long range magnetic order inspite of a huge exchange between the spins of their elementary particles.

The Hall Effect suggests that when magnetic field is applied to electric current carried by charged particles present in a conductor, it causes magnet to bend to the other side of semi-conductor. They are of great interest in physics and material science. Appreciating that frustrated magnets are capable of producing Hall Effect could hold the key to future advances in computing and the creation of devices such as quantum computers.

“To talk about the Hall Effect for neutral particles is an oxymoron, a crazy idea,” said N. Phuan Ong, one of the authors of the study and Eugene Higgins Professor of Physics at Princeton.

Inspite of that, he together with his colleague, Princeton’s Russell Wellman Moore Professor of Chemistry as well as their graduate students Max Hirschberger and Jason Krizan witnessed this unusual behavior in frustrated magnets.

“All of us were very surprised because we work and play in the classical, non-quantum world. Quantum behavior can seem very strange, and this is one example where something that shouldn’t happen is in reality there. It really exists,” said Ong in a statement.
The researchers wanted to find out the reason underlying “discontent” nature of Hall Effect.

In this particular case, the team led by Ong and Moore studied pyrochlores, a class of magnets ‘which should have orderly “spins” at very low temperature, but have been found to have spins that point in random directions, thus rendering them with magnetic frustration properties.’ They attached small electrodes to both sides of crystals and later passed heat through them using microheaters at extremely low temperatures.

The outcome of the experiment, states Ong, stunned the entire team.

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MIT Scientists Found an Invisible Force Field Protecting Earth






Excerpt from
wallstreetotc.com

The invisible force field seems to be taken from a Star-Trek movie script – it’s invisible, it’s steady, and it doesn’t allow harmful cosmic radiation penetrating into our planet’s atmosphere. Massachusetts Institute of Technology researchers say it was first noticed by two NASA spacecrafts orbiting the Van Allen radiation belt on a 7,200 miles (11,000 km) altitude.

This new invisible force field protecting Earth does a very good job at blocking highly radioactive electrons populating Earth’s upper atmospheric region. NASA said these “ultrarelativistic” electrons were extremely aggressive and they easily circulate in space at speeds very close to the speed of light. They also fry everything on their way from spacecrafts to communication satellites. NASA launched two probe crafts, the Van Allen probes, for the sole purpose of studying these electrons and improving the safety level of their spacecrafts and crew.

NASA says although these electrons are attracted towards Earth by its magnetic field, they cannot get closer than 7,200 miles to it due an invisible shield-like barrier, never detected before. This barrier protects Earth from harmful cosmic radiation and has already done a good job in the past by deflecting several solar blows directed towards Earth. It seems that this mysterious force field operates on low frequency electromagnetism, but its source is still uncertain.

In the end, researchers found out that the barrier was probably generated by the plasmaspheric hiss, a phenomenon occurring in the upper parts of the atmosphere. This plasmaspheric hiss deviates from orbit the fast-moving dangerous particles, and sets them on a parallel plan to one of the Earth’s magnetic field lines, forcing them to fall into the atmosphere, collide with neutrally charged particles, and disappear.

Mary Hudson, professor of physics, said the new NASA observations made over more than two years through its Van Allen probes confirmed the inner barrier’s existence, and brought invaluable new information to the particle acceleration theory.

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The Mission to land robot on comet to take final step







Excerpt from  theglobeandmail.com
By Ivan Semeniuk

Half a billion kilometres from Earth and 10 years into its remarkable journey, a small robot is about to plunge into space history.

Pending a final green light from mission controllers on Tuesday night, the robot – nicknamed Philae (fee-lay) – will detach from its mother ship and try to hook itself onto one of the most challenging and mysterious objects in the solar system.



It’s a high-risk manoeuvre with plenty of unknowns. But if it works, then the probe will be able to show us what no one has ever experienced: what it’s like to stand on the surface of a comet.

“Comets are new territory,” said Ralf Gellert, a professor of physics at the University of Guelph. “There could be some big surprises.”

Prof. Gellert should know. Fifteen years ago, he helped build one of the instruments on the dishwasher-size lander that will reveal the comet’s composition. No such direct measurement has been made before. Even designing how the instrument should work was fraught with challenges since there was so little known about what kind of surface the lander might find itself on.

“Is it an ice ball with rock and trace metals, or a rock ball with ice on it … or ice below the surface? We didn’t know,” he said.
And scientists still don’t.

When the European Space Agency launched the Rosetta mission in 2004, the mission’s target – Comet Churyumov-Gerasimenko – was little more than a fuzzy blip in astronomers’ telescopes. But Rosetta just arrived in August and it’s been in orbit around the comet since then.

What was assumed to be a single, homogeneous lump of ice and rock has turned out to be a bizarre-looking object in two parts, arranged a bit like the head and body of a rubber duck. By October, scientists had zeroed in on the head portion, which is four kilometres across at its widest point, and settled on a landing site.

Remote sensing data from Rosetta suggest that the comet is quite porous, with a surface that is as black as coal and somewhat warmer than expected. In other words, Philae will probably not be landing on skating-rink-hard ice. Yet, whether the surface will be crusty like a roadside snowbank, fluffy like cigarette ash, or something else entirely is anyone’s guess.

And while scientists and engineers say they’ve done everything they can think of to maximize the lander’s chance of success, they acknowledge it’s entirely possible that Philae will encounter something it can’t handle and smash to bits or sink into oblivion.


Yet the landing is more than a daring jaunt to see what has never been seen before. Comets are also among the most primitive bodies in the solar system. Each one is an amalgam of ice and rock that has been around since Earth and its sister planets formed billions of years ago. In a sense, comets are the leftovers of that process – primordial fossils from the birth of the solar system.

The instrument Prof. Gellert worked on, known as the alpha particle X-ray spectrometer (APXS), will help illuminate this early period by making precise measurements of the comet’s elemental ingredients.

It is carried on a robot arm that will place a radioactive source near the comet’s surface. The particles and X-rays the comet material gives off as a result of this exposure will provide detailed information about what chemical elements the comet contains. This will be augmented by another experiment designed to drill and extract a comet sample for analysis inside the lander.

Prof. Gellert, who has also been closely involved in NASA’s Mars rover missions, said Rosetta’s long timeline and the many unknowns related to the comet makes this week’s landing a trickier proposition than landing on Mars – but also a tremendously exciting one.

“I think it’s a matter of hope for the best and see what happens.”

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Some like it hot ~ NASA Stumbles Upon A Dead Star That’s 10 Million Times Brighter Than The Sun


bright star
This image of the super-bright pulsar (shown here in magenta) was made using observational data from three telescopes, including NASA’s NuSTAR.



Excerpt from
huffingtonpost.com

Think our sun is bright? NASA says its NuSTAR space-based X-ray telescope has detected a dead star that pumps out as much energy as 10 million suns.

"You might think of this pulsar as the 'Mighty Mouse' of stellar remnants," Dr. Fiona A. Harrison, professor of physics and astronomy at the California Institute of Technology in Pasadena and the principal investigator of the NuSTAR mission, said in a written statement.



The super-bright pulsar--the brightest ever recorded--is located about 12 million light-years from Earth in the Messier 82 galaxy. It's an example of a class of mysterious celestial objects known as ultraluminous X-ray sources, or ULXs.

"We took it for granted that the powerful ULXs must be massive black holes," Dr. Matteo Bachetti, an astrophysicist at the University of Toulouse in France and the lead author of a new study about the pulsar, said in the statement.

The X-rays are believed to be generated by the material as it heats up while falling into a dense object, in this case a pulsar.

"How much visible light is emitted is actually an interesting thing to know," Bachetti told The Huffington Post in an email.

In any case, the surprising discovery has scientists scratching their heads.

"This is going to challenge theorists and pave the way for a new understanding of the diversity of these fascinating objects," Dr. Jeanette Gladstone, a University of Alberta astronomer who wasn't involved in the research, said in the statement.

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So what is a supermassive black hole anyway?


Artist's rendering of a black hole recently discovered in the ultracompact dwarf galaxy M60-UCD1.

csmonitor.com

The discovery of a supermassive black hole inside a tiny dwarf galaxy has shed new light on the potential number of black holes in the universe.

An international team of researchers has discovered a supermassive black hole in M60-UCD1, a dwarf galaxy some 54-million light years away. M60-UCD1 is about 500 times smaller than our own galaxy, the Milky Way, and 1,000 times less massive. The researchers published their findings Wednesday in Nature.

Scientists have previously identified numerous supermassive black holes throughout the universe – including one at the center of the Milky Way. But this is the first time that any of these largest types of black holes have been found in such a small galaxy, says study lead author Anil Seth, an assistant professor of physics and astronomy University of Utah in Salt Lake City. 

The revelation that a supermassive black hole can exist within an ultracompact dwarf galaxy could mean that there might be twice as many of these largest black holes than astronomers previously thought.

Black holes come in several different varieties, all of which are characterized by a dense concentration of mass compressed into a tiny space and a gravitational force so powerful it keeps light from escaping.

The smallest kind, called a primordial black hole, is the size of a single atom, but it contains the mass of a large mountain. The most widely understood black holes are known as stellar black holes and can contain 20 times the mass of the sun within a ball of space with a diameter of about 10 miles. Supermassive black holes can be as vast as the entire solar system and contain as much mass as found in 1 million suns combined.

Primordial black holes are believed to have formed during the early evolution of the universe, shortly after the Big Bang. Stellar black holes are thought to be the result of the collapse of a massive star. The formation of supermassive black holes has so far remained something of a mystery.
“We know supermassive black holes exist in the center of most big galaxies … but we actually don’t know how they’re formed,” says Dr. Seth. “We just know they formed a long time ago.”

Black holes are difficult to study because their tendency to pull light inside their centers renders them effectively invisible. 

Telescopes can observe contextual clues that suggest the presence of a black hole, such as stars orbiting around an apparent void.
“We can actually see stars moving around the center of the supermassive black hole of our galaxy,” Seth says. “It is much more difficult to study smaller galaxies.”

This particular dwarf galaxy happens to have so many stars – and a black hole that is so large – that telltale signs of the black hole were detected by two telescopes, the optical/infrared Gemini North telescope atop Hawaii’s Mauna Kea and the Hubble Space Telescope.

Typically, the size of a black hole is directly proportional to the size of the galaxy. Seth suspects that M60-UCD1 is actually the remains of a much larger galaxy.

“We think that this thing is a galaxy where the outer part of the galaxy has been stripped away by an interaction with another bigger galaxy and that the core has been left behind,” Seth explains.
In general, however, current technology has not yet reached a point that enables astronomers to definitively identify the presence of black holes in smaller galaxies.

By studying this and other black holes, scientists hope to unravel some of the mysteries of the origins of the universe.

“It turns out that black holes actually play a pretty big role in how galaxies form,” Seth says. “To understand our origin story we need to understand the formation of galaxies. And black holes, even though they are just a tiny fraction of all the mass in the galaxy, can play a really important role in their evolution."

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What’s Love Got to Do With It?

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6 July 2011  

Love’s role in Psychiatry Heidi Waltos, RN, MSN, CNS

http://www.retreatatsp.org/latest-news/uncategorized/loves-role-in-psychiatry/

Every few months I ask my boss if he doesn’t agree that l...

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Russian Scientists Have Unlocked The Mysteries Of The Human Aura

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11/05/2011 by Ray, Ray Alex Website

This is something very interesting. Ever since I almost died once myself, and it was exactly the same as everyone is talking about : they saw the ” WHITE LIGHT “which is true BTW. Ev...

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PEMM Motor Harnesses Anti-matter and Electron-Avalanche

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Gary Magrattan's PEMM Electric motor is said to harness the phenomenon of electron avalanche across a spark gap to boost current, voltage, and power. A unique method of harnessing back EMF adds to it's novelty as it nears prod...

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Cold Fusion Steams Ahead at World’s Oldest University

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Progress accelerates as a year long study of Andrea Rossi's Nickel-Hydrogen Cold Fusion technology (energy catalyzer) at the University of Bologna is announced. The birthplace of higher education has become the developmental womb ...

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