The 4th dimension in our case is where the 3D structures including this very Universe combine and exist within changing time frames. 4D structures can’t exist within 3D ones but 3D structures can exist in a 4D just like your drawings exist within that flat paper as lines and points but couldn’t exist in our 3D world by itself. Extra dimensions work the same, like a Matryoshka doll that loses and or gains properties the further you go.

Image: 3D projection of a tesseract undergoing a simple rotation in four dimensional space.

In mathematical physics, Minkowski space or Minkowski spacetime (named after the mathematician Hermann Minkowski) is the mathematical space setting in which Einstein’s theory of special relativity is most conveniently formulated. In this setting the three ordinary dimensions of space are combined with a single dimension of time to form a four-dimensional manifold for representing a spacetime. [**]

In physics, spacetime (also space–time, space time or space–time continuum) is any mathematical model that combines space and time into a single continuum. Spacetime is usually interpreted with space as existing in three dimensions and time playing the role of a fourth dimension that is of a different sort from the spatial dimensions. From a Euclidean space perspective, the universe has three dimensions of space and one of time. By combining space and time into a single manifold, physicists have significantly simplified a large number of physical theories, as well as described in a more uniform way the workings of the universe at both the supergalactic and subatomic levels. [**]

But my favorite explanation of extra dimensions in general is Carl Sagan’s version. His version was based on Flatland: A Romance of Many Dimensions which is an 1884 satirical short story by Edwin Abbott Abbott:

The story is about a two-dimensional world referred to as Flatland which is occupied by geometric figures. Women are simple line-segments, while men are polygons with various numbers of sides. The narrator is a humble square, a member of the social caste of gentlemen and professionals in a society of geometric figures, who guides us through some of the implications of life in two dimensions. The Square has a dream about a visit to a one-dimensional world (Lineland) which is inhabited by “lustrous points”.

He attempts to convince the realm’s ignorant monarch of a second dimension but finds that it is essentially impossible to make him see outside of his eternally straight line.

He is then visited by a three-dimensional sphere, which he cannot comprehend until he sees Spaceland for himself. This Sphere (who remains nameless, like all characters in the novella) visits Flatland at the turn of each millennium to introduce a new apostle to the idea of a third dimension in the hopes of eventually educating the population of Flatland of the existence of Spaceland. From the safety of Spaceland, they are able to observe the leaders of Flatland secretly acknowledging the existence of the sphere and prescribing the silencing of anyone found preaching the truth of Spaceland and the third dimension. After this proclamation is made, many witnesses are massacred or imprisoned (according to caste).

After the Square’s mind is opened to new dimensions, he tries to convince the Sphere of the theoretical possibility of the existence of a fourth (and fifth, and sixth …) spatial dimension.

The depiction above is a 4 dimensional figure as represented by 3 dimensional cubes within cubes to visualize how 4th dimensions may work.

Related: Carl Sagan explains extra dimensions

Baked Exoplanet Gets Lab Treatment


  Don’t get too excited, an exoplanet hasn’t really been captured from the cosmic wilds. And no, one of NASA’s boffins isn’t really taking a pair of tongs to the upper atmosphere of a strangely tiny “hot-Jupiter” being baked by a Bunsen burner. The doctored photo is actually a fun metaphor for this golden age of exoplanetary science. In particularly, it illustrates what one NASA space telescope is doing to understand the chemistry and dynamics of a particular Jupiter-sized exoplanet located some 385 light-years away.
  
  Of course, it would be preferential if we could directly sample an exoplanet’s atmosphere in a lab, but as all exoplanets orbit stars many light-years from the nearest Bunsen burner, astronomers need to think up novel techniques by which the atmospheres of exoplanets can be remotely probed. Enter the Spitzer Space Telescope, NASA’s premier infrared observatory, the inadvertent hero of exo-atmospheric science!
  
  Launched in 2003, Spitzer was designed to observe the infrared universe — particularly star-forming molecular clouds and distant galaxies — but in 2005 it became famous for detecting infrared emissions from extra-solar planets, namely HD 209458b and TrES-1. Since then, Spitzer has continued to notch up some impressive exoplanetary discoveries.
  
  “When Spitzer launched in 2003, we had no idea it would prove to be a giant in the field of exoplanet science,” said Michael Werner, Spitzer project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Now, we’re moving farther into the field of comparative planetary science, where we can look at these objects as a class, and not just as individuals.”
  
  In a new study published in the Astrophysical Journal, astronomers have used Spitzer to watch an exoplanet complete a full orbit around its host star.
  
  Over 6 days, the hot-Jupiter HAT-P-2b passed in front of its star, behind and back in front again. Interestingly, HAT-P-2b’s orbit is highly eccentric, meaning its orbital path takes it only 2.8 million miles from the star’s surface at closest approach and out to 9.3 million miles at its most distant. As a comparison, the solar system’s innermost planet, Mercury, orbits the sun every 88 days and doesn’t come closer than 28 million miles — HAT-P-2b is therefore a roasted planet, where rapid changes in its atmosphere can be expected from extreme heating.
  
  Fortunately, because HAT-P-2b’s orbit is not only compact but also eccentric, astronomers have a wonderful opportunity to see these changes occur over a very short timescale.


Full Article Over at Discovery News

Baked Exoplanet Gets Lab Treatment

Don’t get too excited, an exoplanet hasn’t really been captured from the cosmic wilds. And no, one of NASA’s boffins isn’t really taking a pair of tongs to the upper atmosphere of a strangely tiny “hot-Jupiter” being baked by a Bunsen burner. The doctored photo is actually a fun metaphor for this golden age of exoplanetary science. In particularly, it illustrates what one NASA space telescope is doing to understand the chemistry and dynamics of a particular Jupiter-sized exoplanet located some 385 light-years away.

Of course, it would be preferential if we could directly sample an exoplanet’s atmosphere in a lab, but as all exoplanets orbit stars many light-years from the nearest Bunsen burner, astronomers need to think up novel techniques by which the atmospheres of exoplanets can be remotely probed. Enter the Spitzer Space Telescope, NASA’s premier infrared observatory, the inadvertent hero of exo-atmospheric science!

Launched in 2003, Spitzer was designed to observe the infrared universe — particularly star-forming molecular clouds and distant galaxies — but in 2005 it became famous for detecting infrared emissions from extra-solar planets, namely HD 209458b and TrES-1. Since then, Spitzer has continued to notch up some impressive exoplanetary discoveries.

“When Spitzer launched in 2003, we had no idea it would prove to be a giant in the field of exoplanet science,” said Michael Werner, Spitzer project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “Now, we’re moving farther into the field of comparative planetary science, where we can look at these objects as a class, and not just as individuals.”

In a new study published in the Astrophysical Journal, astronomers have used Spitzer to watch an exoplanet complete a full orbit around its host star.

Over 6 days, the hot-Jupiter HAT-P-2b passed in front of its star, behind and back in front again. Interestingly, HAT-P-2b’s orbit is highly eccentric, meaning its orbital path takes it only 2.8 million miles from the star’s surface at closest approach and out to 9.3 million miles at its most distant. As a comparison, the solar system’s innermost planet, Mercury, orbits the sun every 88 days and doesn’t come closer than 28 million miles — HAT-P-2b is therefore a roasted planet, where rapid changes in its atmosphere can be expected from extreme heating.

Fortunately, because HAT-P-2b’s orbit is not only compact but also eccentric, astronomers have a wonderful opportunity to see these changes occur over a very short timescale.

Full Article Over at Discovery News

When Supermassive Supergiants Go Superboom

Article by Phil Plait via Slate

I have long been fascinated by gamma-ray bursts (or GRBs). These are incredibly violent events: It’s like taking the Sun’s entire lifetime energy output and cramming into a single event that lasts for mere seconds! The energy emitted is so intense, so bright, we can see GRBs from a distance of billions of light years.

Gamma rays themselves are just a form of light, like the kind we see, but with huge energy; each photon is packed with millions or billions of times the energy in a single photon of visible light. Only the most energetic events in the Universe can make them, so if we detect a burst of them coming from the sky, we know something literally disastrous has happened.

We know GRBs come in many flavors. Some last literally for milliseconds, while others stretch on for minutes. We also know different events can cause them, too. Short ones seem to come from merging neutron stars, ultra dense compact objects left over after stars explode. The longer ones occur when massive stars explode, leaving their cores to collapse. In both cases, the huge blast of high-energy gamma rays signals the birth of a black hole.

But astronomers were recently surprised to find a third type of GRB, one that lasts not for minutes, but for hours. Whatever these objects are, they don’t just flash with light, they linger, blasting out far, far more gamma rays for far, far longer than was previously thought. What could do such a thing?

Several ideas were put forth, but new observations provided the linchpin: an ultra-long-duration GRB occurred on Christmas Day in 2010, and its distance was found to be a soul-crushing 7 billion light years away, about halfway across the visible Universe! This left only one possible candidate for the progenitor: a hugely massive star, one so big it dwarfs the Sun into insignificance.

Continue to Full Article..


  How do rockets move in space?
  
  If space is basically a vacuum and void of atmosphere, how do rockets alter the direction and speed of space craft? In other words, how do they “push off” against nothing?
  
  This is a very good question. Isaac Newton worked out the solution and published it in 1687 in his Principia Mathematica. It is phrased as Newton’s 3rd law. I’ll include all 3 below just in case!
  
  1st: A body will remain at rest or at motion with a uniform speed unless it is acted on my an external force.
  2nd: The acceleration of a body with a force acting on it is that force divided by the mass of the body (F=ma)
  3rd: Every action has an equal and opposite reaction.
  
  So the third law basically says that if you shoot out stuff in one direction you will move in the other direction. This is how rockets work in a vacuum. They have a source of fuel which is heated up so that it expands and is pushed out of the rocket. In order to change direction in space rockets have to have little ‘thrusters’ on all sides (you need 6 in total to maneuver completely in 3 dimensions).
  
  Newton’s 3rd law seems contrary to our intuition because on Earth there are lots of sources of friction - providing much easier methods of propulsion, however you might have seen it in action if you have ever blown up a balloon and then let go of it before tying it up. What pushes the balloon all around the room is the air you blew into in escaping.

How do rockets move in space?

If space is basically a vacuum and void of atmosphere, how do rockets alter the direction and speed of space craft? In other words, how do they “push off” against nothing?

This is a very good question. Isaac Newton worked out the solution and published it in 1687 in his Principia Mathematica. It is phrased as Newton’s 3rd law. I’ll include all 3 below just in case!

1st: A body will remain at rest or at motion with a uniform speed unless it is acted on my an external force. 2nd: The acceleration of a body with a force acting on it is that force divided by the mass of the body (F=ma) 3rd: Every action has an equal and opposite reaction.

So the third law basically says that if you shoot out stuff in one direction you will move in the other direction. This is how rockets work in a vacuum. They have a source of fuel which is heated up so that it expands and is pushed out of the rocket. In order to change direction in space rockets have to have little ‘thrusters’ on all sides (you need 6 in total to maneuver completely in 3 dimensions).

Newton’s 3rd law seems contrary to our intuition because on Earth there are lots of sources of friction - providing much easier methods of propulsion, however you might have seen it in action if you have ever blown up a balloon and then let go of it before tying it up. What pushes the balloon all around the room is the air you blew into in escaping.

Black Hole Caught Snacking on ‘Super Jupiter’ Planet


  In a cosmic first, astronomers have discovered a black hole chowing down on what may be a giant rogue planet.
  
  The supermassive black hole didn’t finish off its meal, which scientists say was either a huge Jupiter-like planet wandering freely through space or a brown dwarf, a strange object that’s larger than a planet yet still too small to trigger the internal fusion reactions required to become a full-fledged star.
  
  “This is the first time where we have seen the disruption of a substellar object by a black hole,” study co-author Roland Walter, of the Observatory of Geneva in Switzerland, said in a statement. “We estimate that only its external layers were eaten by the black hole, amounting to about 10 percent of the object’s total mass, and that a denser core has been left orbiting the black hole.”

Black Hole Caught Snacking on ‘Super Jupiter’ Planet

In a cosmic first, astronomers have discovered a black hole chowing down on what may be a giant rogue planet.

The supermassive black hole didn’t finish off its meal, which scientists say was either a huge Jupiter-like planet wandering freely through space or a brown dwarf, a strange object that’s larger than a planet yet still too small to trigger the internal fusion reactions required to become a full-fledged star.

“This is the first time where we have seen the disruption of a substellar object by a black hole,” study co-author Roland Walter, of the Observatory of Geneva in Switzerland, said in a statement. “We estimate that only its external layers were eaten by the black hole, amounting to about 10 percent of the object’s total mass, and that a denser core has been left orbiting the black hole.”

Black Hole Firewall: Trouble On The Edge

Ever wondered what happens to things as they are consumed by the black hole, the left over matter of dead stars? For a time, it used to be okay to assume matter was destroyed once it entered into a black hole, spaghettified and all.. but it turned out that this couldn’t be further away from the truth. NewScientists Anil Ananthaswamy has a wonderful 3 page piece getting into full details of this history and what questions scientists are asking now. If you love black holes, this is a definite recommend. Although registration (completely free!) is required to view the whole article. It’s pretty insightful and accurately presents the problems currently being faced with how black holes do what they do:


  “Paradoxes are good in physics,” reflects John Preskill. “They help to point the way towards important discoveries.” Quantum mechanics and Einstein’s theories of relativity offer plenty to choose from. There’s the cat that can be dead and alive at the same time. Or the Back to the Future-style time traveller who kills his own grandfather, rendering his own birth impossible. Or the twins who disagree on their age after one returns from a near light-speed trip to a neighbouring star. Each perplexing scenario forces us to examine the fine print of the problem, thereby advancing our understanding of the theory behind it. A case in point is Einstein, whose own theories came from trying to resolve the paradoxes of his time.
  
  Image: Ring of fireSam Chivers
  
  Now Preskill, a theoretical physicist at the California Institute of Technology in Pasadena, is scratching his head over the latest one to surface. Nicknamed the black hole firewall paradox, it comes about when you consider what happens to someone falling into a black hole.
  
  With the nearest black hole more than 1000 light years away, the question is very much a theoretical one. Yet just by studying such a possibility, physicists are hoping to make a breakthrough in their efforts to combine general relativity and quantum mechanics into a theory of quantum gravity – one of the most intractable problems in physics today.
  
  Black holes have long been fertile breeding grounds for paradoxes. Back in 1974, Stephen Hawking, along with Jacob Bekenstein of the Hebrew University in Jerusalem, Israel, famously showed that black holes are not entirely black. Instead, they radiate energy known as Hawking radiation comprising photons and other quantum particles – an agonisingly slow process that eventually causes the black hole to evaporate completely.
  
  Hawking spotted a problem with this picture. The radiation seemed so random that he surmised it couldn’t carry any information about the stuff that had fallen in. So as the black hole evaporates, the information it holds must eventually disappear. Yet this is in direct conflict with a central tenet of quantum physics, which says that information cannot be destroyed. The black hole information paradox was born.
  
  Over the decades, physicists have struggled with this paradox. Hawking thought that black holes destroyed information and the answer was to question quantum mechanics. Others disagreed. After all, Hawking’s idea came from his efforts to meld general relativity and quantum mechanics – a mathematical feat so elusive that he was forced to make approximations. Preskill even made a bet with Hawking that black holes don’t destroy information.
  
  Several arguments suggest that Hawking was wrong. One of the most compelling comes from thinking about what happens as the evaporating black hole gets smaller and smaller. If information can’t escape or be destroyed, then more and more has to be stored in an ever-shrinking volume. But if this is the case, quantum theory says the probability for making a tiny black hole increases from virtually nothing to almost infinity wherever matter collides against matter. “You should have seen it at the Large Hadron Collider, you should have seen it at Fermilab, you should have seen it in tiny room-sized particle accelerators from the 1930s,” says Don Marolf, a theorist at the University of California in Santa Barbara (UCSB). “You should see it when you go and jump up and down on the grass.”
  
  Obviously that hasn’t happened. The other possibility – that matter and the information it carries can leak out from a black hole – is unlikely. Any material that falls in would need to travel faster than light to escape the black hole’s fearsome gravity.
  
  Perhaps, instead, the answer lies with the Hawking radiation itself. Maybe it isn’t so featureless. “A common reaction was that Hawking had simply been careless,” says Joseph Polchinski, also at UCSB. “It wasn’t that information was lost, it was that he hadn’t kept track of it enough.”
  
  Yet all early efforts to do away with the paradox proved unsuccessful. “Hawking had identified a really deep problem,” says Polchinski.
  
  As it happened, Hawking changed his mind in 2004, partly due to work by an Argentinian physicist called Juan Maldacena (see “Hawking’s change of heart”). Black holes don’t destroy information after all, he conceded. He honoured the bet he made with Preskill and presented him with an encyclopaedia of baseball, which Preskill likened to a black hole, because it was heavy and it took effort to get information out of it.
  
  Into The Abyss..


[Full Article]

Black Hole Firewall: Trouble On The Edge

Ever wondered what happens to things as they are consumed by the black hole, the left over matter of dead stars? For a time, it used to be okay to assume matter was destroyed once it entered into a black hole, spaghettified and all.. but it turned out that this couldn’t be further away from the truth. NewScientists Anil Ananthaswamy has a wonderful 3 page piece getting into full details of this history and what questions scientists are asking now. If you love black holes, this is a definite recommend. Although registration (completely free!) is required to view the whole article. It’s pretty insightful and accurately presents the problems currently being faced with how black holes do what they do:

“Paradoxes are good in physics,” reflects John Preskill. “They help to point the way towards important discoveries.” Quantum mechanics and Einstein’s theories of relativity offer plenty to choose from. There’s the cat that can be dead and alive at the same time. Or the Back to the Future-style time traveller who kills his own grandfather, rendering his own birth impossible. Or the twins who disagree on their age after one returns from a near light-speed trip to a neighbouring star. Each perplexing scenario forces us to examine the fine print of the problem, thereby advancing our understanding of the theory behind it. A case in point is Einstein, whose own theories came from trying to resolve the paradoxes of his time.

Image: Ring of fireSam Chivers

Now Preskill, a theoretical physicist at the California Institute of Technology in Pasadena, is scratching his head over the latest one to surface. Nicknamed the black hole firewall paradox, it comes about when you consider what happens to someone falling into a black hole.

With the nearest black hole more than 1000 light years away, the question is very much a theoretical one. Yet just by studying such a possibility, physicists are hoping to make a breakthrough in their efforts to combine general relativity and quantum mechanics into a theory of quantum gravity – one of the most intractable problems in physics today.

Black holes have long been fertile breeding grounds for paradoxes. Back in 1974, Stephen Hawking, along with Jacob Bekenstein of the Hebrew University in Jerusalem, Israel, famously showed that black holes are not entirely black. Instead, they radiate energy known as Hawking radiation comprising photons and other quantum particles – an agonisingly slow process that eventually causes the black hole to evaporate completely.

Hawking spotted a problem with this picture. The radiation seemed so random that he surmised it couldn’t carry any information about the stuff that had fallen in. So as the black hole evaporates, the information it holds must eventually disappear. Yet this is in direct conflict with a central tenet of quantum physics, which says that information cannot be destroyed. The black hole information paradox was born.

Over the decades, physicists have struggled with this paradox. Hawking thought that black holes destroyed information and the answer was to question quantum mechanics. Others disagreed. After all, Hawking’s idea came from his efforts to meld general relativity and quantum mechanics – a mathematical feat so elusive that he was forced to make approximations. Preskill even made a bet with Hawking that black holes don’t destroy information.

Several arguments suggest that Hawking was wrong. One of the most compelling comes from thinking about what happens as the evaporating black hole gets smaller and smaller. If information can’t escape or be destroyed, then more and more has to be stored in an ever-shrinking volume. But if this is the case, quantum theory says the probability for making a tiny black hole increases from virtually nothing to almost infinity wherever matter collides against matter. “You should have seen it at the Large Hadron Collider, you should have seen it at Fermilab, you should have seen it in tiny room-sized particle accelerators from the 1930s,” says Don Marolf, a theorist at the University of California in Santa Barbara (UCSB). “You should see it when you go and jump up and down on the grass.”

Obviously that hasn’t happened. The other possibility – that matter and the information it carries can leak out from a black hole – is unlikely. Any material that falls in would need to travel faster than light to escape the black hole’s fearsome gravity.

Perhaps, instead, the answer lies with the Hawking radiation itself. Maybe it isn’t so featureless. “A common reaction was that Hawking had simply been careless,” says Joseph Polchinski, also at UCSB. “It wasn’t that information was lost, it was that he hadn’t kept track of it enough.”

Yet all early efforts to do away with the paradox proved unsuccessful. “Hawking had identified a really deep problem,” says Polchinski.

As it happened, Hawking changed his mind in 2004, partly due to work by an Argentinian physicist called Juan Maldacena (see “Hawking’s change of heart”). Black holes don’t destroy information after all, he conceded. He honoured the bet he made with Preskill and presented him with an encyclopaedia of baseball, which Preskill likened to a black hole, because it was heavy and it took effort to get information out of it.

Into The Abyss..

[Full Article]

Man Arrested at Large Hadron Collider Claims He’s From the Future


  A would-be saboteur arrested today at the Large Hadron Collider in Switzerland made the bizarre claim that he was from the future. Eloi Cole, a strangely dressed young man, said that he had travelled back in time to prevent the LHC from destroying the world.
  
  The LHC successfully collided particles at record force earlier this week, a milestone Mr Cole was attempting to disrupt by stopping supplies of Mountain Dew to the experiment’s vending machines. He also claimed responsibility for the infamous baguette sabotage in November last year.
  
  Mr Cole was seized by Swiss police after CERN security guards spotted him rooting around in bins. He explained that he was looking for fuel for his ‘time machine power unit’, a device that resembled a kitchen blender.
  
  Police said Mr Cole, who was wearing a bow tie and rather too much tweed for his age, would not reveal his country of origin. “Countries do not exist where I am from. The discovery of the Higgs boson led to limitless power, the elimination of poverty and Kit-Kats for everyone. It is a communist chocolate hellhole and I’m here to stop it ever happening.”
  
  This isn’t the first time time-travel has been blamed for mishaps at the LHC. Last year, the Japanese physicist Masao Ninomiya and Danish string-theory pioneer Holger Bech Nielsen put forward the hypothesis that the Higgs boson was so “abhorrent” that it somehow caused a ripple in time that prevented its own discovery.
  
  Professor Brian Cox, a CERN physicist and full-time rock’n’roll TV scientist, was sympathetic to Mr Cole. “Bless him, he sounds harmless enough. At least he didn’t mention bloody black holes.”
  
  Mr Cole was taken to a secure mental health facility in Geneva but later disappeared from his cell. Police are baffled, but not that bothered.

Man Arrested at Large Hadron Collider Claims He’s From the Future

A would-be saboteur arrested today at the Large Hadron Collider in Switzerland made the bizarre claim that he was from the future. Eloi Cole, a strangely dressed young man, said that he had travelled back in time to prevent the LHC from destroying the world.

The LHC successfully collided particles at record force earlier this week, a milestone Mr Cole was attempting to disrupt by stopping supplies of Mountain Dew to the experiment’s vending machines. He also claimed responsibility for the infamous baguette sabotage in November last year.

Mr Cole was seized by Swiss police after CERN security guards spotted him rooting around in bins. He explained that he was looking for fuel for his ‘time machine power unit’, a device that resembled a kitchen blender.

Police said Mr Cole, who was wearing a bow tie and rather too much tweed for his age, would not reveal his country of origin. “Countries do not exist where I am from. The discovery of the Higgs boson led to limitless power, the elimination of poverty and Kit-Kats for everyone. It is a communist chocolate hellhole and I’m here to stop it ever happening.”

This isn’t the first time time-travel has been blamed for mishaps at the LHC. Last year, the Japanese physicist Masao Ninomiya and Danish string-theory pioneer Holger Bech Nielsen put forward the hypothesis that the Higgs boson was so “abhorrent” that it somehow caused a ripple in time that prevented its own discovery.

Professor Brian Cox, a CERN physicist and full-time rock’n’roll TV scientist, was sympathetic to Mr Cole. “Bless him, he sounds harmless enough. At least he didn’t mention bloody black holes.”

Mr Cole was taken to a secure mental health facility in Geneva but later disappeared from his cell. Police are baffled, but not that bothered.

Three Observatories Shed Light on Newly Discovered Super Nova Remnant

Meet G306.3-0.9. Using the data from NASA’s Swift, the Galactic Australia Telescope Compact Array (ATCA) and Chandra X-Ray observatory astrophysicists have been able to detect a never before seen Super Nova Remnant (SNR). The image above displays valuable information using data from these three observatories. Francis Reddy writes for NASA:

While performing an extensive X-ray survey of our galaxy’s central regions, NASA’s Swift satellite has uncovered the previously unknown remains of a shattered star. Designated G306.3–0.9 after the coordinates of its sky position, the new object ranks among the youngest-known supernova remnants in our Milky Way galaxy.

“Astronomers have previously cataloged more than 300 supernova remnants in the galaxy,” said lead scientist Mark Reynolds, a postdoctoral researcher at the University of Michigan in Ann Arbor. “Our analysis indicates that G306.3–0.9 is likely less than 2,500 years old, making it one of the 20 youngest remnants identified.”

Astronomers estimate that a supernova explosion occurs once or twice a century in the Milky Way. The expanding blast wave and hot stellar debris slowly dissipate over hundreds of thousands of years, eventually mixing with and becoming indistinguishable from interstellar gas.

Journal Reference: G306.3-0.9: A newly discovered young galactic supernova remnant

A Quantum Internet at the Speed of Light?


  The realization of quantum networks is one of the major challenges of modern physics. Now, new research shows how high-quality photons can be generated from ‘solid-state’ chips, bringing us closer to the quantum ‘internet’.
  
  Image: An artist’s impression of distributed qubits (the bright spots) linked to each other via photons (the light beams). The colours of the beams represent that the optical frequency of the photons in each link can be tailored to the needs of the network. Credit: Mete Atature
  
  The number of transistors on a microprocessor continues to double every two years, amazingly holding firm to a prediction by Intel co-founder Gordon Moore almost 50 years ago. If this is to continue, conceptual and technical advances harnessing the power of quantum mechanics in microchips will need to be investigated within the next decade.
  
  “We are at the dawn of quantum-enabled technologies, and quantum computing is one of many thrilling possibilities,” says Dr Mete Atature from University of Cambridge Department of Physics. “Our results in particular suggest that multiple distant qubits in a distributed quantum network can share a highly coherent and programmable photonic interconnect that is liberated from the detrimental properties of the chips. Consequently, the ability to generate quantum entanglement and perform quantum teleportation between distant quantum-dot spin qubits with very high fidelity is now only a matter of time.”
  
  Developing a distributed quantum network is one promising direction pursued by many researchers today. A variety of solid-state systems are currently being investigated as candidates for quantum bits of information, or qubits, as well as a number of approaches to quantum computing protocols, and the race is on for identifying the best combination.
  
  Ref: Laser-like photons signal major step towards quantum ‘Internet’

A Quantum Internet at the Speed of Light?

The realization of quantum networks is one of the major challenges of modern physics. Now, new research shows how high-quality photons can be generated from ‘solid-state’ chips, bringing us closer to the quantum ‘internet’.

Image: An artist’s impression of distributed qubits (the bright spots) linked to each other via photons (the light beams). The colours of the beams represent that the optical frequency of the photons in each link can be tailored to the needs of the network. Credit: Mete Atature

The number of transistors on a microprocessor continues to double every two years, amazingly holding firm to a prediction by Intel co-founder Gordon Moore almost 50 years ago. If this is to continue, conceptual and technical advances harnessing the power of quantum mechanics in microchips will need to be investigated within the next decade.

“We are at the dawn of quantum-enabled technologies, and quantum computing is one of many thrilling possibilities,” says Dr Mete Atature from University of Cambridge Department of Physics. “Our results in particular suggest that multiple distant qubits in a distributed quantum network can share a highly coherent and programmable photonic interconnect that is liberated from the detrimental properties of the chips. Consequently, the ability to generate quantum entanglement and perform quantum teleportation between distant quantum-dot spin qubits with very high fidelity is now only a matter of time.”

Developing a distributed quantum network is one promising direction pursued by many researchers today. A variety of solid-state systems are currently being investigated as candidates for quantum bits of information, or qubits, as well as a number of approaches to quantum computing protocols, and the race is on for identifying the best combination.

Ref: Laser-like photons signal major step towards quantum ‘Internet’


  Betelgeuse
  
  However you pronounce its name, the star Betelgeuse is hard to miss on a clear winter’s night. Representing the top left shoulder of Orion the Hunter it blazes a bright red colour. At over 600 light years away Betelgeuse is not particularly close, but it shines 100,000 times as brightly as our Sun.
  
  Betelgeuse is a “red supergiant” star which is nearing the end of its life. As it has swelled in size over the past few hundred thousand years, currently measuring around 1000 times the size of our Sun, the massive star has been shedding its outer layers. This material is made of gas and dust, which has cooled over time and is seen here in far-infrared light by Herschel.
  
  The ejected outer layers of the star expanded outwards until they hit the surrounding material, creating the arc-like structures seen to the left of the image. These arcs are a bow shock, similar to the wave that travels in front of a ship moving through water, and are caused by Betelgeuse’s motion through the surrounding gas cloud at around 30 km/s (70,000 mph).
  
  Further to the left is what appears to be a straight wall of gas and dust, the origin of which is uncertain. It is very hard to measure distances in images such as this, so the wall could be much futher away or closer to Earth than Betelgeuse - essentially in the foreground or background.

Betelgeuse

However you pronounce its name, the star Betelgeuse is hard to miss on a clear winter’s night. Representing the top left shoulder of Orion the Hunter it blazes a bright red colour. At over 600 light years away Betelgeuse is not particularly close, but it shines 100,000 times as brightly as our Sun.

Betelgeuse is a “red supergiant” star which is nearing the end of its life. As it has swelled in size over the past few hundred thousand years, currently measuring around 1000 times the size of our Sun, the massive star has been shedding its outer layers. This material is made of gas and dust, which has cooled over time and is seen here in far-infrared light by Herschel.

The ejected outer layers of the star expanded outwards until they hit the surrounding material, creating the arc-like structures seen to the left of the image. These arcs are a bow shock, similar to the wave that travels in front of a ship moving through water, and are caused by Betelgeuse’s motion through the surrounding gas cloud at around 30 km/s (70,000 mph).

Further to the left is what appears to be a straight wall of gas and dust, the origin of which is uncertain. It is very hard to measure distances in images such as this, so the wall could be much futher away or closer to Earth than Betelgeuse - essentially in the foreground or background.

Vortex Tied in Knots

A UChicago physics team has created the first knotted vortex in a lab, untangling deep questions

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University of Chicago physicists have succeeding in creating a vortex knot—a feat akin to tying a smoke ring into a knot. Linked and knotted vortex loops have existed in theory for more than a century, but creating them in the laboratory had previously eluded scientists.

Vortex knots should, in principle, be persistent, stable phenomena. “The unexpected thing is that they’re not,” said Dustin Kleckner, a postdoctoral scientist at UChicago’s James Franck Institute. “They seem to break up in a particular way. They stretch themselves, which is a weird behavior.”

This behavior culminates in what the UChicago researchers call “reconnection events.” In these events, the loops elongate, begin to circulate in opposite directions, move toward each other and collide (the reconnection). Parts of the vortices then annihilate other parts, changing their configuration from linked or knotted into one that is unlinked or unknotted.

Kleckner and William Irvine, assistant professor in physics, report their findings on the creation and dynamics of vortex rings in Nature Physics, published online Sunday, March 3. Their work relates to deep questions in a variety of physics subfields, including turbulence, plasma physics, ordinary fluids and the more exotic superfluids. Knotted structures are thought to occur in all these phenomena but are difficult or impossible to observe.

In future research, Irvine and Kleckner hope to perform some of their experiments at larger scale to investigate whether size would lend greater stability to vortex rings. They also are investigating the fine-scale features of the vortices and whether “knottedness” is, or can be, conserved in fine-scale twisting of the vortex loops. “This is not something we presently know,” Kleckner said.

(via Vortex loops could untie knotty physics problems)

Solar Mass

Image: Corona Light

The solar mass is a standard unit of mass in astronomy that is used to indicate the masses of other stars, as well as clusters, nebulae and galaxies. It is equal to the mass of the Sun, about two nonillion kilograms:

The above mass is about 332,946 times the mass of the Earth or 1,048 times the mass of Jupiter.


  Polarized Window Frost
  
  The photo above shows both frost crystals and two curious multi-colored ribbons on a window of my home in Rimavska Sobota, Slovakia.
  
  The variegated ribbons are actually drips of meltwater imaged using a circular polarizer lens. A polarizer filter or lens acts to recombine the two distinct rays of light that emerge when a beam of sunlight propagates through a slurry of partially frozen crystals as in this case.
  
  Because the rays were out of phase when recombined, the new rays contain nearly every visible wavelength. It should be noted that these colors might also be attributable to diffraction processes caused by minute cracks in the window glass. — Photography / Summary: Daniela Rapava; Jim Foster

Polarized Window Frost

The photo above shows both frost crystals and two curious multi-colored ribbons on a window of my home in Rimavska Sobota, Slovakia.

The variegated ribbons are actually drips of meltwater imaged using a circular polarizer lens. A polarizer filter or lens acts to recombine the two distinct rays of light that emerge when a beam of sunlight propagates through a slurry of partially frozen crystals as in this case.

Because the rays were out of phase when recombined, the new rays contain nearly every visible wavelength. It should be noted that these colors might also be attributable to diffraction processes caused by minute cracks in the window glass. — Photography / Summary: Daniela Rapava; Jim Foster

Science Fiction Meets Science Fact: Reddit-Inspired Star Wars Physics Homework

Wired writer Rhet Allain gets into some serious scifi homework I recommend to both science and physics enthusiasts, and star wars fans. Here he offers up a list of objectives in the form of a homework assignment for you to get into a bit of physics (or lack of) through the Star Wars Universe:

Image Cred

I recently did a Reddit AMA on the Science of Star Wars. If you like, you can check some of the very interesting questions (along with my answers). Or even better, I will list some Reddit inspired questions in Star Wars that you can turn in for homework. The usual rule applies, if you wait too long to turn in the homework, I might answer them instead.


-Now for the questions from Reddit. You might want to take a peek at my answers on the AMA, but that won’t be good enough for a full homework answer.

-How hot is a light saber? (from roguepublichealth) I think you have to first figure out what a light saber actually is and why it glows.

-How much material would be needed to build the Death Star (from astanisic) You will obviously need some estimates here. If you want a second question, how long would it take to put this Death Star together. You can answer for both the first (Episode IV) and second (Episode VI) Death Stars – which are different sizes.

-How can you make artificial gravity in a spaceship (other than spinning) (from awhit13). I think this question might be accomplished with a literature review. Surely someone out there has come up with an explanation for how these spaceships could have artificial gravity in them. Oh, and if you just say “interial dampeners”, you will fail.

-What is more deadly, blasters or kinetic weapons (conventional bullets) (from JimmyDeLaRustles). I guess you need to first figure out what a blaster bolt actually is made of. My guess is that it is plasma. Next you need to say how something is deadly – is it the kinetic energy, the total energy, the momentum?

-Why doesn’t an AT-AT fall over when it walks? (from RagingLlamas) You might want to examine the Hoth battle scene from Episode V.

-How far in the past do the Star Wars movies take place? Clearly, there isn’t an exact answer. You can get a range of ages though. Also, how far away is this galaxy – a range is fine too.

-Where is the center of mass for a light saber that is thrown? (from BrooklynKnight) Check out the scene where Vader throws his light saber.

There you go. No cheating.

Oh, a bonus essay question: Compare and contrast the physics of Star Wars vs. the physics of Star Trek.