Hi Wolram,
good question! I would guess that, as you suggest, major science advances probably don't always require expensive equipment if the experimentalist has a highly original insight and brings a new technology to the problem.
Significant research can also "piggyback" on other research. In astronomy, data can be collected for one purpose and then a year or two later someone can see how to use that same data to test some other (possibly more interesting) idea. So the data is free, for the second test. It doesn't require new instruments. But this was not what you asked about.
Atyy,
I think you are right about the interest and potential importance of the proposal of Raymond Y. Chiao. I heard about this a couple of years ago, around the time that he won the Willis Lamb award. I don't know what happened. Around that time Chiao moved from UC Berkeley to UC Merced (the new campus of the University of California). I don't know anything about the research facilities he has available and what success he has had carrying out this proposed experiment.
In case anyone is interested, here is something on the Lamb Medal that has a bio for Chiao
http://www.lambmedal.org/2006/index.html
There was a funny coincidence. The Lamb Medal is a new prize for laser science and quantum optics, I think. It was started some time in 1990s. In 2005, in September, they announced that it would be awarded to Chiao and Glauber and somebody else. Then couple of weeks later, in October, the Nobel committee annouced that Roy Glauber is awarded the physics Nobel! So Chiao, in a certain sense, came within a cat's whisker of catching a Nobel.
To my mind, it seems possible that Chiao is onto something that is totally original but also valid. Planck mass is something like 22 micrograms, like an oil droplet or a flea. In a sense macroscopic---you could see it with a magnifying glass I imagine. So he wants to have two electrically charged droplets, each with Planck mass, and they should do a dance involving both electromagnetic force and gravity force.
Then there should be two pairs of droplets. Use electromagnetism to drive the first pair in oscillation, making them produce a tiny ripple of gravity wave, which then travels to the other pair making them oscillate. the second pair oscillating will produce an EM signal which can be detected.
There could be something wrong with the idea. Some Achilles heel, like the charges do not stay on the surface of the droplets, or the droplets are not rigid enough. A non-expert spectator like myself cannot really guess. Something could go wrong. But then again it might be OK.
