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NASA’s Voyager probes are truly going where no one has gone before. Gliding silently toward the stars, 9 billion miles from Earth, they are beaming back news from the most distant, unexplored reaches of the solar system.

Mission scientists say the probes have just sent back some very big news indeed.

It’s bubbly out there.

According to computer models, the bubbles are large, about 100 million miles wide, so it would take the speedy probes weeks to cross just one of them. Voyager 1 entered the “foam-zone” around 2007, and Voyager 2 followed about a year later. At first researchers didn’t understand what the Voyagers were sensing–but now they have a good idea.

“The sun’s magnetic field extends all the way to the edge of the solar system,” explains Opher. “Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina’s skirt. Far, far away from the sun, where the Voyagers are now, the folds of the skirt bunch up.”

When a magnetic field gets severely folded like this, interesting things can happen. Lines of magnetic force criss-cross, and “reconnect”. (Magnetic reconnection is the same energetic process underlying solar flares.) The crowded folds of the skirt reorganize themselves, sometimes explosively, into foamy magnetic bubbles.

“We never expected to find such a foam at the edge of the solar system, but there it is!” says Opher’s colleague, University of Maryland physicist Jim Drake.

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Like many physicists, Michio Kaku thinks our universe will end in a “big freeze.” However, unlike many physicists, he thinks we might be able to avoid this fate by slipping into a parallel universe.”

One of the most fascinating discoveries of our new century may be imminent if the Large Hadron Collider outside Geneva produces nano-blackholes when it goes live again. According to the best current physics, such nano blackholes could not be produced with the energy levels the LHC can generate, but could only come into being if a parallel universe were providing extra gravitational input. Versions of multiverse theory suggest that there is at least one other universe very close to our own, perhaps only a millimeter away. This makes it possible that some of the effects, especially gravity, “leak through,” which could be responsible for the production of dark energy and dark matter that make up 96% of the universe.

“The multiverse is no longer a model, it is a consequence of our models,” says Aurelien Barrau, particle physicist at CERN.

While it hasn’t been proven yet, many highly respected and credible scientists are now saying there’s reason to believe that parallel dimensions could very well be more than figments of our imaginations.

“The idea of multiple universes is more than a fantastic invention—it appears naturally within several scientific theories, and deserves to be taken seriously,” stated Aurelien Barrau, a French particle physicist at the European Organization for Nuclear Research (CERN).

There are a variety of competing theories based on the idea of parallel universes, but the most basic idea is that if the universe is infinite, then everything that could possibly occur has happened, is happening, or will happen.

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There’s something exciting afoot in the world of cosmology. Last month, Roger Penrose at the University of Oxford and Vahe Gurzadyan at Yerevan State University in Armenia announced that they had found patterns of concentric circles in the cosmic microwave background, the echo of the Big Bang.

This, they say, is exactly what you’d expect if the universe were eternally cyclical. By that, they mean that each cycle ends with a big bang that starts the next cycle. In this model, the universe is a kind of cosmic Russian Doll, with all previous universes contained within the current one.

That’s an extraordinary discovery: evidence of something that occurred before the (conventional) Big Bang.

Today, another group says they’ve found something else in the echo of the Big Bang. These guys start with a different model of the universe called eternal inflation. In this way of thinking, the universe we see is merely a bubble in a much larger cosmos. This cosmos is filled with other bubbles, all of which are other universes where the laws of physics may be dramatically different to ours.

These bubbles probably had a violent past, jostling together and leaving “cosmic bruises” where they touched. If so, these bruises ought to be visible today in the cosmic microwave background.

Now Stephen Feeney at University College London and a few pals say they’ve found tentative evidence of this bruising in the form of circular patterns in cosmic microwave background. In fact, they’ve found four bruises, implying that our universe must have smashed into other bubbles at least four times in the past.

Again, this is an extraordinary result: the first evidence of universes beyond our own.

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It would certainly seem so if you are reading these words online, but in fact you are not actually “seeing” the computer screen in front of you. What you see are photons of light bouncing off the screen (and generated by the internal electronics of the screen itself), which pass through the hole in the iris of your eye, through the liquid medium inside your eye, wending their way through the bipolar and ganglion cells to strike the rods and cones at the back of your retina. These photons of light carry just enough energy to bend the molecules inside the rods and cones to change the electrochemical balance inside these cells, causing them to fire, or have what neuroscientists call an “action potential.”

From there the nerve impulse races along the neural pathway from the retina to the back of the brain, leaping from neuron to neuron across tiny gaps called synaptic clefts by means of neurotransmitter substances that flow across those gaps. Finally, they encounter the visual cortex, where other neurons record the signals that have been transduced from those photons of light, and reconstruct the image that is out there in the world.

Out of an incomprehensible number of data signals pouring in from the senses, the brain forms models of faces, tables, cars, trees, and every conceivable known (and even unknown — imagined) object and event. It does this through something called neural binding. A “red circle” would be an example of two neural network inputs (“red” and “circle”) bound into one percept of a red circle. Downstream neural inputs, such as those closer to muscles and sensory organs, converge as they move upstream through convergence zones, which are brain regions that integrate information coming from various neural inputs (eyes, ears, touch, etc.) You end up perceiving a whole object instead of countless fragments of an image. This is why you are seeing an entire computer screen with a meaningful block of text in front of you right now, and not just a jumble of data.

According to the University of Cambridge cosmologist Stephen Hawking, however, not even science can pull us out of such belief dependency. In his new book, The Grand Design, co-authored with the Caltech mathematician Leonard Mlodinow, Hawking presents a philosophy of science he calls “model-dependent realism,” which is based on the assumption that our brains form models of the world from sensory input, that we use the model most successful at explaining events and assume that the models match reality (even if they do not), and that when more than one model makes accurate predictions “we are free to use whichever model is most convenient.” Employing this method, Hawking and Mlodinow claim that “it is pointless to ask whether a model is real, only whether it agrees with observation.”

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