Tag Archives | Physics

U.S. Electrical Grid Too Crappy to Be Vulnerable to Terrorist Attack, Say Physicists

Interesting article from Annalee Newitz on io9.com:

U.S. Electrical GridThe US government worries that terrorists could take down the country’s electrical grid just by hitting a small node in the system. But a new study reveals the grid is too unreliable for that kind of attack.

Last year, network theorists published some papers suggesting that terrorists could take down the entire US electrical grid by attacking a small, remote power station.

But new research shows that network theory models, which great for analyzing many complex systems, don’t work for patchwork systems like the US electrical grid. Basically, the grid was set up so haphazardly that you’d have to take out a major node before you’d affect the entire thing.

Science Daily sums up: [The] electric grid is probably more secure that many people realize — because it is so unpredictable. This, of course, makes it hard to improve its reliability (in another line of research, [study co-author Paul] Hines has explored why the rate of blackouts in the United States hasn’t improved in decades), but the up-side of this fact is that it would be hard for a terrorist to bring large parts of the grid down by attacking just one small part.

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Mysterious Force Influencing NASA Probe in Deep Space

Pioneer10This is bizarre but cool that it was/is happening (feel free to mention updates on this research). Robert Matthews writes in the Telegraph:

Researchers say Pioneer 10, which took the first close-up pictures of Jupiter before leaving our solar system in 1983, is being pulled back to the sun by an unknown force. The effect shows no sign of getting weaker as the spacecraft travels deeper into space, and scientists are considering the possibility that the probe has revealed a new force of nature.

Dr Philip Laing, a member of the research team tracking the craft, said: “We have examined every mechanism and theory we can think of and so far nothing works. “If the effect is real, it will have a big impact on cosmology and spacecraft navigation,” said Dr Laing, of the Aerospace Corporation of California.

Pioneer 10 was launched by Nasa on March 2 1972, and with Pioneer 11, its twin, revolutionised astronomy with detailed images of Jupiter and Saturn.

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Does The Past Exist Yet?

past-present-futureThe future has yet to be determined, but what about the past? This recent Huffington Post piece discusses the possibility that what you do in the present shapes both future and past — “historical events such as who killed JFK, might depend on events that haven’t occurred yet.”

Recent discoveries require us to rethink our understanding of history. “The histories of the universe,” said renowned physicist Stephen Hawking “depend on what is being measured, contrary to the usual idea that the universe has an objective observer-independent history.”

Is it possible we live and die in a world of illusions? Physics tells us that objects exist in a suspended state until observed, when they collapse in to just one outcome. Paradoxically, whether events happened in the past may not be determined until sometime in your future — and may even depend on actions that you haven’t taken yet.

In 2002, scientists carried out an amazing experiment, which showed that particles of light “photons” knew — in advance −- what their distant twins would do in the future.

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Stephen Hawking: God Was Not Needed To Create The Universe

Stephen Hawking says the Big Bang was the result of the inevitable laws of physics and did not need God to spark the creation of the Universe -- reported in the Telegraph:
The scientist has claimed that no divine force was needed to explain why the Universe was formed. In his latest book, The Grand Design, an extract of which is published in Eureka magazine in The Times, Hawking said: “Because there is a law such as gravity, the Universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the Universe exists, why we exist.” He added: “It is not necessary to invoke God to light the blue touch paper and set the Universe going.”...
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There Was No Big Bang at the Start of the Universe

Hubble_ultra_deep_field Alasdair Wilkins writes on io9.com:

A new theory explains the accelerating universe without invoking mysterious, unseen dark energy to account for the expansion. But it also gets rid of singularities, an unchanging speed of light … and the most famous astrophysical phenomenon of all, the Big Bang.

The observation of certain supernovas in the late 1990s led astronomers to the very unexpected discovery that the universe is expanding, and that the expansion is speeding up. There was nothing in the existing laws of physics to account for this, and so the only solution was dark energy — a mysterious force so named because we’ve never detected it, and yet it has to make up 75% of all the energy and mass in the universe for it to account for this cosmic acceleration. Also, the existence of dark energy weakens the supposedly inviolate law of conservation of energy, if not negates it completely.

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Time Travel Theory Avoids Grandfather Paradox

From Physorg.com:

The possibility of going back in time only to kill your ancestors and prevent your own birth has posed a serious problem for potential time travelers, not even considering the technical details of building a time machine. But a new theory proposed by physicists at MIT suggests that this grandfather paradox could be avoided by using quantum teleportation and “post-selecting” what a time traveler could and could not do. So while murdering one’s relatives is unfortunately possible in the present time, such actions would be strictly forbidden if you were to try them during a trip to the past.

The model of time travel proposed by Seth Lloyd, et al., in a recent paper at arXiv.org arises from their investigation of the quantum mechanics of closed timelike curves (CTCs) and search for a theory of gravity. In simple terms, a CTC is a path of spacetime that returns to its starting point.

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Social Physics with Kyle Findlay

Kyle FindlayVia Technoccult:

Klint Finley: What, as a “social physicist,” do you actually do?

Kyle Findlay: Well, at the moment I’m on my own in this “field,” if you can call it that. It just seems like the best description of what I do and what interests me so hopefully it sticks.

Basically, my interest is in understanding how people act as groups. As emergent entities that have their own (hopefully) predictable and describable topological forms. That’s the lofty idea anyway. And the tools of chaos theory, systems theory, network theory, physics, mathematics, etc. help describe this.

Do you have a background in physical sciences?

None at all. I studied “business science” at the University of Cape Town. My first job was for a company with a strong academic background, started by a professor of religion and a professor of statistics. They used a 5-dimensional catastrophe cusp model to describe people’s relationships with ideas.

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Is This What God Sounds Like?

Higgs-BosonFascinating developments from the Large Hadron Collider, as the BBC reports that the so-called “God particle” has been simulated as sound:

Scientists have simulated the sounds set to be made by sub-atomic particles such as the Higgs boson when they are produced at the Large Hadron Collider.

Their aim is to develop a means for physicists at Cern to “listen to the data” and pick out the Higgs particle if and when they finally detect it.

Dr Lily Asquith modelled data from the giant Atlas experiment at the LHC. She worked with sound engineers to convert data expected from collisions at the LHC into sounds.

“If the energy is close to you, you will hear a low pitch and if it’s further away you hear a higher pitch,” the particle physicist told BBC News. “If it’s lots of energy it will be louder and if it’s just a bit of energy it will be quieter.”

The £6bn LHC machine on the Swiss-French border is designed to shed light on fundamental questions in physics.

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ESC Chicago Keynote Makes Case For Time Travel

Karen Field reports that theoretical physicist Ronald Mallett is on a lifelong mission to build a time machine. His theory of a time machine, based on Einstein’s Theory of Relativity, involves creating a circulating beam of light and exploiting the energy to produce a gravitational field, at RF Designline:

Ronald Mallett, a professor of theoretical physics at the University of Connecticut, gave a mind-bending keynote speech on the physics of time travel to an enthralled audience at the Embedded Systems Conference here Tuesday morning, describing how black holes, blue giant stars, and worm holes (tunnels that connect the mouths of black holes)—some of the strangest things in the Universe—illustrate (at least in theory) the potential for time travel some day.

And that day, Mallett claimed, is not so far in the future as one might think.

“Time travel one of mankind’s oldest fantasies. But is it really possible? All of us have wondered what’s going to happen in the future, and we’ve contemplated the question, ‘What if I could back and change something in my past?” said Mallet.

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Mysterious Radio Waves Emitted From Nearby Galaxy

Galaxy M82Stephen Battersby writes on New Scientist:
There is something strange in the cosmic neighbourhood. An unknown object in the nearby galaxy M82 has started sending out radio waves, and the emission does not look like anything seen anywhere in the universe before. "We don't know what it is," says co-discoverer Tom Muxlow of Jodrell Bank Centre for Astrophysics near Macclesfield, UK. The thing appeared in May last year, while Muxlow and his colleagues were monitoring an unrelated stellar explosion in M82 using the MERLIN network of radio telescopes in the UK. A bright spot of radio emission emerged over only a few days, quite rapidly in astronomical terms. Since then it has done very little except baffle astrophysicists. It certainly does not fit the pattern of radio emissions from supernovae: they usually get brighter...
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