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Quantum Suicide
The ICHEP 10 comes to an end today in Paris. As I, however, browse over all that was talked about during this conference, I preceded to ponder over a thought experiment that some scientists had mentioned. Surely you remember the Large Hadron Collider. It's a device built by physicists to test some theories some of us will never understand, at the improbable cost of destroying the world. The device has failed to work numerous times ago. Some physicists came up with a reason why which centers on the role of... sabotage, from unknown time-traveling forces:
A pair of otherwise distinguished physicists have suggested that the hypothesized Higgs boson, which physicists hope to produce with the collider, might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather. ...
According to the so-called Standard Model that rules almost all physics, the Higgs is responsible for imbuing other elementary particles with mass. “It must be our prediction that all Higgs producing machines shall have bad luck,” Dr. Nielsen said in an e-mail message. In an unpublished essay, Dr. Nielson said of the theory, “Well, one could even almost say that we have a model for God.” It is their guess, he went on, “that He rather hates Higgs particles, and attempts to avoid them.”
This malign influence from the future, they argue, could explain why the United States Superconducting Supercollider, also designed to find the Higgs, was canceled in 1993 after billions of dollars had already been spent, an event so unlikely that Dr. Nielsen calls it an “anti-miracle.”
You'd think that this is the sort of nonsense which one could dismiss off-hand. But there were some more trouble:
The Large Hadron Collider, the world's most powerful particle accelerator, just cannot catch a break. First, a coolant leak destroyed some of the magnets that guide the energy beam. Then LHC officials postponed the restart of the machine to add additional safety features. Now, a bird dropping a piece of bread on a section of the accelerator has, according to the Register, shut down the whole operation.
While it is a paradox to go back in time and kill your grandfather, physicists agree there is no paradox if you go back in time and save him from being hit by a bus. In the case of the Higgs and the collider, it is as if something is going back in time to keep the universe from being hit by a bus. Although just why the Higgs would be a catastrophe is not clear. If we knew, presumably, we wouldn’t be trying to make one.
I haven't heard this thrown around, but it should also be quantum suicide at play. Imagine you flip a coin and kill yourself if you hit heads. You flip a coin, and find yourself split into one world in which you survive and another in which you cease to be a conscious entity. But from the point of view of the non-dead copies of the you, it just came up tails. You can keep flipping coins. You'll die half of the time. But from your own point of view, because you can only observe the world in which you survive, it's always tails. You are, they say, immortal in a quantum sense.
Similarly; humanity may only survive in those states of the world in which the LHC fails to operate; so of course we are alive, look around, and find that the device does not work.
I should add that none of this makes sense to me. That's fine, as there's no reason to think that our intuitions--which evolved at non-relativistic speeds etc. etc.--need to match up to how the world works. But I still very much hope that physicists one day discover that we live in a reasonable universe
If the Earth Stood Still
The following is not a futuristic scenario. It is not science fiction. It is a demonstration of the capabilities of GIS to model the results of an extremely unlikely, yet intellectually fascinating query: What would happen if the earth stopped spinning over a period of a few decades? ArcGIS was used to perform complex raster analysis and volumetric computations and generate maps that visualize these results.
If earth ceased rotating about its axis but continued revolving around the sun and its axis of rotation maintained the same inclination, the length of a year would remain the same, but a day would last as long as a year. In this fictitious scenario, the sequential disappearance of centrifugal force would cause a catastrophic change in climate and disastrous geologic adjustments (expressed as devastating earthquakes) to the transforming equipotential gravitational state.
The lack of the centrifugal effect would result in the gravity of the earth being the only significant force controlling the extent of the oceans. Prominent celestial bodies such as the moon and sun would also play a role, but because of their distance from the earth, their impact on the extent of global oceans would be negligible. If the earth's gravity alone was responsible for creating a new geography, the huge bulge of oceanic water-which is now about 8 km high at the equator-would migrate to where a stationary earth's gravity would be the strongest. This bulge is attributed to the centrifugal effect of earth's spinning with a linear speed of 1,667 km/hour at the equator. The existing equatorial water bulge also inflates the ellipsoidal shape of the globe itself. If the earth stood still, the oceans would gradually migrate toward the poles and cause land in the equatorial region to emerge. This would eventually result in a huge equatorial megacontinent and two large polar oceans. The line that delineates the areas that hydrologically contribute to one or the other ocean would follow the equator if the earth was a perfect ellipsoid. However, due to the significant relief of both the continents and the ocean floor, the hypothetical global divide between the areas that hydrologically contribute to one or another ocean deviates from the equator significantly.Analogous to the well-known U.S. Continental Divide, this would be the border separating two giant hemispherical watersheds of the new circumpolar oceans.
That's from the folks at the ESRI.
Interestingly, the earth will eventually stop spinning due to negative tidal acceleration. The moon's tidal forces on the Earth's oceans have since the moon's inception cause days to be about 2 hours longer than they were about 620 million years ago. At that time, there were about 400 days in a year. However, the time when the earth will eventually stop spinning will never come. Due to the Sun's increase of radiation, the earth's ocean (there's only one ocean since they are all connected) will be completely vaporize in about 2.1 billion years from now which will remove the bulk of the mass that causes tidal friction.Again, due to recent calculations, a time when a day is a month long will also never come because the sun will by then evolve into a red giant and destroy both the Earth and the Moon. Cool stuff.
entertain physics, don't ponder upon it
The sciences of astronomy and physics, specifically quantum physics, has always fascinated me. I've tried often to keep abreast of the sciences with any free time that I may gather. Consequent of the many hours spent on the MIT Open Course Ware site, my understanding has certainly come a long way further from my physics class in 10th grade. Recently, I came across a paper written by a physicist named Jia Liu entitled Dark Matter as a Possible New Energy Source for Future Rocket Technology and later this article. An excerpt:
Yes I know. Just don't think about it too much.Crane first started thinking about artificial black holes 12 years ago when physicist Lee Smolin, now at Canada's Perimeter Institute for Theoretical Physics in Waterloo, Ontario, asked Crane to read the manuscript of his book The Life of the Cosmos.
Nobody knows what happens at the singularity of a black hole, the point where space and time become so warped that the laws of relativity break down. In his book, Smolin suggested that a new universe could be created and bud off. So universes in which black holes are likely to arise will give birth to more and more such universes.
This means that our universe could be a baby universe, and is more likely to have come from one that is good at making black holes than one that isn't. Crane then wondered what would happen if intelligent civilizations could make black holes. This would mean that life in these universes played a key role in the proliferation of baby universes. Smolin felt the idea was too outlandish and left it out of his book. But Crane has been thinking about it on and off for the last decade.
He believes we are seeing Darwinian selection operating on the largest possible scale: only universes that contain life can make black holes and then go on to give birth to other universes, while the lifeless universes are an evolutionary dead end. His latest calculations made him realize how uncanny it was that there could be a black hole at just the right size for powering a starship.
"Why is there such a sweet spot?" he asks. The only reason for an intelligent civilization to make a black hole, he sees, is so it can travel the universe. "If this hypothesis is right," he says, "we live in a universe that is optimized for building starships!"
