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This is an amusing perspective on religion and God. Evidence is provided in the link below. http://www.thechurchofgoogle.org/Scripture/Proof_Google_Is_God.html

See Space.com article [Edit: come to think of it, I posted a link to the arxiv blog about this a couple of weeks ago ...]

Looks like there are some fascinating things going on in cosmology at the moment. People have often said that if there are things that exist outside of the physical universe that starts from the big bang we wouldn't be able to observe them, but my immediate thought was that such things have happened before and we've extended our observations in unanticipated ways. Apparently if its true about our universe being one of many, the existence of others may be detectable by their effect on ours, and these effects may be huge, and they may be starting to be detected. Looks like Laura Mersini-Houghton's ideas are as hot in this area as Hawking's were in the theory of black holes.

Check this out. http://www.acceleratingfuture.com/michael/blog/2006/04/the-bootes-void/

Interesting post on the Technology Review arxiv blog shows how to make an event horizon (opposite way round to in a black hole).

Is it possible to make x^2 - y^3 a product of 2 or 3 expressions? Meaning: ( )*( ) = x^2 - y^3 ( )*( )*( ) = x^2 - y^3 I can't find that...

I found this image and explanation interesting and beautiful. (taken from NASA.gov) Spiral Extraordinaire Scientists have yet to discover what caused the strange spiral structure. Nor do they know why it glows. The glow may be caused by light reflected from nearby stars. As for the spiral itself, current supposition is that this is the result of a star in a binary star system entering the planetary nebula phase, when its outer atmosphere is ejected. Given the expansion rate of the spiral gas, a new layer must appear about every 800 years, a close match to the time it takes for the two stars to orbit each other. The above image was taken in near-infrared light by the Hubble Space Telescope. Image Credit: NASA, ESA, Hubble, R. Sahai (JPL)

2010 Nobel prize for physics

A question for fellow mathematical Platonists: What is your "pet" rebuttal to the problem of access (numbers are causally inert which means that we shouldn't be able to recognize them (by causal theory of knowledge), but Platonism is committed to us knowing them therefore Platonism must be false)? Is the causal theory of knowlege correct, in your opnion? Certainly, it is not necessary that the causal theory of knowledge is always correct (for example, the famous EPR thought experiment in physics), but is it not correct most of the time? Can we link the access problem to possible solutions to the mind-body problem? etc.

I recall antimatter being matter moving backwards in time. I also know that most time machines are said to be able to move backwards in time, rather than making a wormhole (at least in the movie click, time could rewind). But wouldn't that mean that whatever it rewinding is actually antimatter. This would mean a time machine is actually an Einstein reactor? (Einstein reactor is what I call anything that converts E=mc^2 perfectly)

Apparently no-one has ever done this before. Maxwell's demon implemented - information powered motor

It's widely known that one cause of ageing related illnesses is that the telomeres that protect the ends of a chromosome shorten as cells divide, eventually causing loss of or damage to parts of the chromosome. So the discovery of natural telomere lengthening chemicals seems promising.

[Please tell me if the following is incomprehensible, boring, erroneous, interesting or intriguing (etc.) ] For a long while I've been aware of an argument that suggests though the mechanism for Hawking radiation makes perfect sense, it will not ever be observed by someone at a distance from a black hole, but I think I've finally convinced myself it will be (unsurprisingly - Hawking is better than me at this stuff ). But in doing so, it makes it clear just how weird the extremes of general relativity combined with quantum mechanics can be. Imagine the simplest case for formation of a black hole, where there is a perfectly symmetrical spherical shell of matter collapsing under its own gravitational attraction. If big enough it would be reasonable to ignore the things that would confuse the perfect collapse (interactions within the material). In fact if really huge the sphere of matter could be quite diffuse and still form a black hole. [Using a spherical shell of matter rather than a more real-worldly solid sphere of matter just makes the discussion a bit simpler] Anyhow, as far as I know, general relativity predicts that if you watch this from a distance, a strange thing happens. The collapse accelerates as the sphere gets smaller for quite a while, but in addition the sphere gets gravitationally red-shifted, which has the effect of appearing to slow the collapse. At some point to the remote observer the collapse seems to start to slow down, and eventually gets to a state where the shell appears to be almost frozen, massively red-shifted, just above the radius where the event horizon for this much mass would be expected to be. Shrinking the last little bit to the event horizon seems to take literally eternity from the point of view of the remote observer. A key point is that for eternity, every atom in the collapsing matter is (in principle) observable by the observer at a distance. Now if Hawking radiation is observed at some time in the future, the following process must occur (many, many times). A pair of photons must appear in the space near where the event horizon would be expected to form. The one of the photons with negative energy manages to get past the event horizon in the time given to it by Heisenberg's uncertainty principle (delta t * delta E >= h) to fall into the black hole and the one with positive energy manages to escape from the gravitational field completely. The photon that escaped goes all the way to the remote observer. But here's a conceptual problem. The remote observer can see all the original matter hovering at a radius just above where the event horizon will form, and now sees this radiation being emitted by the black hole. If the remote observer placed an entire sphere of photon detectors at a large distance from the black hole, according to Hawking's theory, he can expect to see the entire mass of the black hole emitted as black hole radiation over a finite (albeit very long) time. But meanwhile the entire shell of matter is still visible contracting above the event horizon. So how can the effect of the formation of the event horizon get to him even though the event horizon appears never to form, by a straight shortest line of sight view? After the entire mass of the black hole has been transformed to black body radiation, wouldn't it be possible (in principle) to fly a spaceship on a trajectory that takes it very, very close to the event horizon, and to scoop up a little of the mass that formed the black hole. But isn't this paradoxical? Perhaps the simplest explanation is that the virtual photon pair can form just outside the shell of matter, when it is very, very close to the event horizon. This means the escaping photon starts from a point nearer to the remote observer than the shell of matter, and due to gravitational time dilation, being a little nearer can mean the signal gets to the remote observer a very great time earlier (the shell appears takes an infinite length of time to fall the last micron to the event horizon). And that's why I now do believe Hawking radiation can be observed.

Is there a trick to factoring the quadratic: ax(to the power of four) + bx³ + cx² + dx + e My actual problem is: z^4 + 2z^3 - 4z^2 - 2z + 3. All help appreaciated! :)

An article by David Biello in Scientific American: http://www.scientificamerican.com/podcast/episode.cfm?id=global-warming-is-undeniable-10-08-01 "Global warming first emerged clearly in the 1990s and has become more evident with each passing year. The last decade was the hottest such span on record and is very likely to be surpassed as the 21st century progresses. A new report from the U.S. National Oceanic and Atmospheric Administration lists 10 indicators that global warming is happening: rising humidity; rising sea-surface temperature as well as heat stored in deeper waters; shrinking sea ice, glacier and springtime snow cover; rising temperatures over land and sea; and rising sea levels. All point to a rapidly warming world. And all are based on actual observations, from satellites high in the sky to meteorological stations in the middle of a Kansas cornfield. You can debate how bad global warming will be or what to do about it, but it's hard to deny it's happening anymore. The physics of greenhouse gases trapping heat are clear. The politics are murkier. Legislative efforts to combat climate change have failed in the U.S. But the Environmental Protection Agency plans to curb greenhouse gas emissions—noting that rising temperatures and a dangerous human impact on climate are undeniable."

Does anyone know any really esoteric energy sources, I don't mean the kind like using oranges to power iphone chargers, I mean serious "impossible" energy sources to harvest. I don't really know of the validity of Hawking radiation, or cosmic strings, but if they are existent, they would be the kind of esoteric I mean. Cosmic strings, because if there's a moving string, then we can have it pull Earth via gravity, and in it's wake will be lots and lots (not sure how much) of blue shifted radiation. Also, in Asimov's book, The Gods Themselves, there's an alternate universe where Plutonium is stable and it can be sent to Earth and the radiation is harvested as energy. And if my creativity isn't getting the better of me, would it be somehow possible to harvest gravity waves? And just wondering about black holes, their gravity should in theory accelerate stuff past c if anything falls in. Since that's impossible, the object should gain mass as it falls, and when it hits the center, about 5 times times as much mass is added to the black hole as was dumped in. Hawking radiation could be harvested, and we'd get 5 times as much mass as we put in. Convert 4/5 of it to energy via Einstein reactor, put the rest back in the black hole. Infinite energy device, no?

I saw this poem in The Black Hole Wars: (to the tune of the macarena) The Maldacena You start with the brane and the brane is BPS and you go near the brane and the space is ADS who knows what it means I don't, I confess Eh Maldacena! Super Yang-Mills with very large N gravity on a sphere, flux without end who says they're the same, holographic, he contends Eh Maldacena! Black holes used to be a great mystery, how we used d-branes to compute 'd energy and when d-brane is hot, the free energy Eh Maldacena! M-theory is finished, Juan has great repute the black hole we have mastered QCD we can compute. Too bad the glue spectrum is still in some dispute Eh Maldacena! -Jeff Harvey

"Two photon walk"

Greed can be hazardous