Is all this work on string theory and multiple dimensions and extra universes still science? That’s the question physicist Sean Carroll and writer John Horgan recently debated. Carroll, of the California Institute of Technology, also blogs regularly for Cosmic Variance, and he wrote out a detailed post explaining his position. Obviously, as a cosmologist who works full-time on these seemingly preposterous ideas, he is a bit biased. He’s not the guy you’d expect to stop and say it isn’t real science. But his piece on the subject does effectively explain why he and, one assumes, other theoretical physicists working on these problems think this way. An excerpt:
“The next thing to understand is that all these crazy speculations about multiverses and extra dimensions originate in an attempt to understand phenomena that we observe right here in the nearby world. Gravity and quantum mechanics both exist–very few people doubt that. And therefore, we want a theory that can encompass both of them. By a very explicit chain of reasoning . . . we are led to superstrings in ten dimensions. And then we try to bring that theory back into contact with the observed world around us.”
Read more here.
It’s not bling, but this nano-ring may be the key to a quantum computer
Granted, it will be far too small for her to show off to her friends, but if your potential fiancée has a love of science, she just might accept this bauble over something flashier. It’s the world’s smallest diamond ring, created by a group of Australian physicists. The ring measures just 5 microns wide and 300 nanometers thick. And no, it’s not really for advertising your engagement. The ring is actually part of a device used to produce and detect single photons.
The group that developed it, at Australia’s multi-university Centre for Quantum Computer Technology, is doing the fundamental research that could pave the way towards a quantum computer–the next, next generation of thinking machines.
The most advanced eye on Earth gives its owner a fighting chance
The mantis shrimp (which oddly is neither a mantis nor a shrimp, but a crustacean that resembles both) has arguably the most complicated visual system of any animal on Earth. Its compound eyes sit on independently moving stalks and can see colors ranging from ultra-violet to infra-red. Each eye is divided into three regions for tracking motion, forms, depth, and color. All of this, it is theorized, is done without the aid of its tiny brain. (It’s also got claws that can smash through glass, but that we’ll save for another article). Now add to this an entirely new kind of vision previously unknown: the mantis shrimp can see circular polarized light.
We humans can see the effects of linear polarized light when we put on polarized sunglasses and go out on a boat. Linear polarization is observed when transparent materials reflect light, so on a sunny day, the ocean’s surface will look glassy to us. Put on polarized sunglasses and the glare is eliminated. Circular polarization is a bit more complicated. It has to do with out-of-phase stereo imaging, which can best be explained by the effect you get when you put on 3-D glasses and watch a movie in 3-D. That’s circular polarization.
Why the mantis shrimp has the ability to, in effect, put on 3-D glasses is still a mystery. But Professor Justin Marshall (the researcher who discovered it), from the Queensland Brain Institute, surmises it has something to do with sex. Only the males are able to see this way, so his theory is it is some as of yet unknown communication for mating. “[We] humans only have three color channels,” he said. “These little guys have 12, and can see both linear and circular polarized light—it is remarkable.”
