Good reality TV

I have a low opinion of most reality television shows. The things they make people do feel way too contrived, not to mention that a lot of the supposedly dramatic moments feel contrived, too. But there are some rare exceptions, such as the show God Loves ME Best!. It helps that it's not a real reality show but rather a parody of a reality show.

The "premise" of the show is to gather people with various religious beliefs and show how they live together. I find it very funny the way they satirize all of the represented religions (and non-religion). Even us atheists are shown in an unflattering light. And the opening sequence reminds me of the Brady Bunch.

Building space-time

The July issue of Scientific American has an interesting article on how our four-dimensional space-time could arise from basic building blocks that self-organize in a quantum superposition. Their approach, called causal dynamical triangulations, is an extension of Euclidean quantum gravity. But instead of just seeing what a superposition of self-organized building blocks that assemble arbitrarily looks like, which turns out to be a bunched up and very messy space-time with plain Euclidean quantum gravity, they imposed causality on each building block so that they can only assemble in specific ways. Their computer simulations show that the result would be a space-time that looks much like our own on large scales.

They show that at large-scales space-time should be a smooth four-dimensional space-time, but at microscopic scales the dimension of space-time shrinks down to two, which is a concept I have difficulty wrapping my head around. The concept of dimension they used is the spectral dimension, which is determined by how fast something spreads over time. For integer values of the spectral dimension I think I can understand how it relates to the more conventional notion of dimension (the number of values necessary to locate something uniquely), but fractional values of the spectral dimension is rather hard to understand.

And if the theory is correct, then the built-in causality would imply that wormholes and time travel would not be possible. While it's cool that ordinary space-time could be built from first principles, it would be a bummer in that faster-than-light travel or direct observation of historical events would not be possible.

Causal dynamical triangulations is an interesting approach, independent from string theory, which shows promise given their simulation results. It's also nice to see that string theory has not completely monopolized theoretical physics, despite the lack of any experimental predictions or confirmation. While I don't think that string theory is a dead end, I do like to see a more balanced allocation of resources to alternatives, considering that all of the current theories of quantum gravity are somewhat lacking in experimental support. I also have to admit that I find background-independent theories, where space-time itself arises from the laws of physics instead of being a pre-defined background, more aesthetically pleasing in a philosophical sense.

Some of the questions I have about causal dynamical triangulations are:

  • With space-time being built out of basic building blocks, do these constitute a sort of "aether" which defines an absolute space-time? What happens to Lorentz invariance?
  • Do the simulations only show an empty vacuum universe, or does it reduce to the theory of general relativity in the classical limit?
  • Would the incorporation of causality in the building blocks imply a built-in arrow of time in the laws of physics?

And some questions that they still need to figure out:

  • Is there a fundamental building block to space-time, or is space-time infinitely divisible?
  • Would it have implications for the origin of the universe?
  • Are there any feasible experimental predictions that would differentiate causal dynamical triangulations from other theories?

Evaporating ice on Mars

The Mars Phoenix Lander has found direct photographic evidence of ice near the surface of Mars. It was uncertain whether the white material found when it dug a trench was ice, salts, or some other mineral, but it managed to take photographs of some of the white material disappearing. This could only be due to the white material subliming, which most probably means that it's ice.

It's exciting to get direct contact with a substantial ice layer on the red planet. Maybe in the far future it will make Mars exploration and colonization much more feasible. While I thought we would have to wait for results from the TEGA lab instrument, it's a pleasant surprise to find confirmation of water in the form of ice with photographic evidence.

The before and after photographs of the ice subliming in the trench are courtesy of NASA.

Ice or salt?

Has the Mars Phoenix Lander uncovered ice that was buried under the soil? While the blast from its thrusters when it landed may have uncovered ice, it's not reachable by the robotic arm. In a trench dug up by the arm last week, named "Dodo-Goldilocks", the lander may have uncovered ice, which is much more obvious in a color picture than in a black and white photograph. Seeing white on a planet whose most popular color is red is a nice change.

Is the exposed white material ice or salts? Or is it something else entirely? Only after analysis with the TEGA instrument on the lander will we know.

The image of the "Dodo-Goldilocks" trench is courtesy of NASA.

Terrorism naivete

I've got to agree with Obama that Republicans have been less than effective with terrorism. I find it very ironic when Republicans say that they're the ones with the proper mindset while Democrats are naive about terrorism.

I have got to wonder just exactly what the Bush administration has accomplished concerning terrorism. In fact, I wonder if the administration has accomplished anything positive at all. The two positive things that they've managed is the ousting of Saddam Hussein and the capture of lower-level participants in the 9/11 terror attack. However, the former is eclipsed by the terrorism that is rampant in Iraq, while the latter is shadowed by the fact that the key figure, Osama bin Laden, is still at large.

The administration has managed many negative accomplishments, though. They have managed to achieve record federal budget deficit and debt. They've cultivated a culture of ignoring civil rights. They're eroding freedom of religion by funding faith-based initiatives with little to no accountability. They invaded Iraq, willfully ignoring evidence that contradicted their justification from weapons of mass destruction, and caused enormous loss of life and resources that is still ongoing today. And they still have not managed to pacify the Taliban, a group much closer to Al Qaeda than Sadam Hussein ever was. The economy itself is in a severe downturn, partly due to the zeal the administration has shown in preventing the oversight of corporations and the finance sector.

The administration's track record with terrorism itself is rather dismal. They don't have a clue to the anthrax attacks despite the passage of seven years. They failed to stop other terrorist attacks such as the Beltway sniper or bombings such as the one at a San Diego courthouse. In fact, they seemed to have made the situation worse.

While I don't know if the Democrats will be any better, I simply cannot give any credence to the idea that Republicans are any good against terrorism. They've been good at politically taking advantage of terrorism, but there is no indication at all that their partisan policies actually help fight terrorism.