I do not know mean of　Einstein@home's project.

Every mew observational technique has changed our view of the Universo. Think of radioastronomy (pulsars!), X-ray astronomy from satellites, Infrared astronomy. etc. Shakespeare knew this when he wrote "there are more things between heaven and earth than those conceived by your philosophy". I am quoting from memory, but the meaning is precise. Think of "dark energy" amd "dark matter" which may represent the greatest part of our Universe. What we see is just a minor part.

Basic research is like a baby. You never know how important it will grow up to be.

My interest in supporting this project comes from two different reasons.

First, as has been said already, every new window we open to the universe has taught us more. Early man had only his own eyes, then Gallileo added the telescope and we could actually see objects going round other objects for the first time.

Much later, radio was invented and when people had got bored listening to news and music, someone decided to point an antenna at the sky - and noticed we can see some stars and some galaxies by radio waves; and we can see some things that we can't see using only optical telescopes. The pulsar was first discovered by radio, and only later discovered using visible light - just one example.

I think it is amusing that we are now also looking for pulsars to be the very first object we hope to 'see' in the new astronomy. There is also a weak link to SETI here - when pulsars were first spotted one idea was that this kind of repetitive signal was from aliens! It was a while before anyone figured out a natural cause for them. Now we use distributed computing techniques developped for the deliberate search for aliens, but to find pulsars in a new kind of 'telescope'. Well it amuses me anyway...

X-ray, gamma-ray have added to our understanding as well. All of these have one thing in common - they are all electromagnetic.

Gravity wave astronomy, if GW exist at all, will teach us more because it is a bigger step than the change from naked eye to telescope. We don't know what it will teach, and that not-knowing is part of the fun.

Second, GW are predicted by Einstein's theory of General Relativity. There are four possibilities.

1. Maybe someone will find GW and they will fit the theory - in which case measurements about the exact size of the waves will help us to fill in some of the missing numbers in the theory.

2. Maybe someone will find GW and the numbers won't fit. Even more interesting - the theory will have to be changed or a new theory started.

3. Maybe someone will not find GW, but they can't rule out that they could be found with more sensitive apparatus. This is the only boring outcome.

4. Maybe the apparatus is so good that when no GW are found we can say Einstein must be wrong in this detail - we are sure that our experiment can find the smallest possible GW that could exist in Einstein's theory.

At present we might get result 1, 2, or 3. Result 1 and 2 are immediate winners, at least if you are interested in knowing more about a theory that has been accepted for nearly a century.

Result 3 means that the scientists will rush off (stopping only to fill in the grant apps) to make the detectors better. Eventually with the same method Bruce and friends are using, we will be sure to get result 1, 2, or 4. Will we be at s6 then? Or s17? or s99? Will it be an improved LIGO at the same site, or the European observatory, or one that is not yet built? I don't know, that is partly a choice of the taxpayers of the different countries.

Maybe you think I joke about the grant apps? I don't. The funding agency will not pay for a super-duper detector while there is the possibility that a plain old detector will do the job. Quite right too -- some nation's taxpayers foot the bill for that. So result 3 is important, but for political reasons not so much for the immediate science.

What I do know, is that for as long as the scientists can get the money to build and run the detectors, they will be asking for our help. Our help means they don't have to ask for so much money for the computing power which must give them an advantage when asking for more money.

To summarize:

Outcome 1 & 2 means the work then goes on to become GW astronomy. Outcome 3 is only an interim outcome and means more of the same but better (at least if the taxpayer agrees). Outcome 4 means the line of experiments comes to a logical end, but still having made a huge leap forward in our understanding of Einstein's theories.

I hope that helps.

River~~