To their defence, though the application technique sucks, it does have a lot of implications. An organic solar cell with 34% efficiency is really amazing actually. The solar cells used in the space program are expensive thin film gallium-arsenide that are about 24% efficient. The solar cells that we can go out and buy on the market are amorphous, poly-crystalline and single crystal Si cells that have efficiencies from 7%-16% or so. Even at low efficiencies of 16%, if you cover a roof with solar cells in Ca (Which is cheaper than you might imagine given all the government subsidized loans and rebates for this kind of thing), you can power all of an energy efficient house during the day, as well as sell back some energy (which the utilities are required to buy) while you are at work. So yeah, you still buy energy at night, but it ends up as no net energy cost after installation. My point is, if they really mean that 34% efficiency, this has the potential to seriously reduce the power problems in most of the united states, since it would make solar viable for places in the US that are exposed to fewer days of sunlight, AND make it more affordable for all.
This discovery just shows how much money is being poured into research that focuses on biological systems for answers to disease. I mean, granted, the first anti-biotic was derived from penicillium, but a lot of drug research in the past 25 years have been in synthesis due to how easy it is to mass produce. Lately however there has been renewed interest in studying anti-cancer, anti-viral and anti-biotic byproducts of many strains of algae, micro-algae and bacteria, as well as some slightly higher level life forms. Its pretty neat since nature has had a few billion years to develop these defences and they are generally a good deal more effective than the compounds we come up with in the lab. Of course, ever with money in mind, the the major reason for this renewed interest is the belief that we are reaching the point when we can figure out how to mass-culture the drug producing life-form, as well as synthesize it artificially in the lab.
Well... I wasn't forgetting about relativity, just misinterpreting slightly. the medium argument, yes i was forgeting about that. Your argument about photons being definitely a particle is not really supported by a variety of neat experiments.
A single photon can still have a "frequency" and thus a single quanta of energy, momentum or "mass," if you will, one can definitely produce single photons of different energy, or momentum (for you who does not believe in energy), in the same medium; its done everyday and it is even measurable. Frequency can be merely a way of expressing the amount of energy or momentum a single photon has.
I am not so happy with your claim that energy does not exist... one could argue that mass does not exist, it is merely energy condensed to a slow vibration. Anyway... these are fairly fundamental things and the only point of my post was really to say that I do remember relativity, albeit imperfectly.
I'm going to be all nit-picky and say that electrons are pretty darn small, essentially point particles, while photons are just energy so they have no size, so the size argument doesn't make any sense. Furthermore photons really only travel at one speed, c (the speed of light, go figure), so they are often going much faster than electrons unless you've got highly relativistic electrons. However, their frequency (not their speed) defines their momentum, as a blue photon has more momentum than a red photon: p=h/lambda (where lambda is wavelength).
Pretty sure though that your average blue photon (lambda = 400nm) has p=10^-28 kgm/s about, while an electron will have between p=0.. 10^-25kgm/s at non-relativistic speeds... of course above a certain speed you end up in relativistic realms where you have to multiply the whole thing by gamma, but I digress. Guess my point is... a photon or a bunch of them can certainly affect the momentum of an electron.
hell... I could be wrong... I haven't been in school for a while.
Slashdot Mirror
I'm so glad it blew up!
that sounds weird to say...
Weird, I didn't know there were many mongolians at cambridge...
rant complete
A single photon can still have a "frequency" and thus a single quanta of energy, momentum or "mass," if you will, one can definitely produce single photons of different energy, or momentum (for you who does not believe in energy), in the same medium; its done everyday and it is even measurable. Frequency can be merely a way of expressing the amount of energy or momentum a single photon has.
I am not so happy with your claim that energy does not exist... one could argue that mass does not exist, it is merely energy condensed to a slow vibration. Anyway... these are fairly fundamental things and the only point of my post was really to say that I do remember relativity, albeit imperfectly.
I'm going to be all nit-picky and say that electrons are pretty darn small, essentially point particles, while photons are just energy so they have no size, so the size argument doesn't make any sense. Furthermore photons really only travel at one speed, c (the speed of light, go figure), so they are often going much faster than electrons unless you've got highly relativistic electrons. However, their frequency (not their speed) defines their momentum, as a blue photon has more momentum than a red photon: p=h/lambda (where lambda is wavelength).
Pretty sure though that your average blue photon (lambda = 400nm) has p=10^-28 kgm/s about, while an electron will have between p=0hell... I could be wrong... I haven't been in school for a while.
-your sig, it taunted me!