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SETI Running Out of Money
New submitter opusman writes "According to an Australian space analyst, SETI is running out of money. Despite needing only $2 million a year, a relatively small amount in space industry terms, they are facing a financial crisis. From the article: 'Getting on board a spacecraft is tricky. There are few places for professional astronauts. Even when Richard Branson and a group of other visionaries makes space tourism more affordable, it will still cost huge sums to fly. But getting a foothold in the greatest quest of all can be done for just a few tens of donated dollars. Which is why it beggars belief that the SETI quest is on its knees.'"
Googling SETI donate gave the first link:
https://www.teamseti.org/donate
SETI just isn't in the public consciousness as much as it used to be. Kickstarter or getting Justin Beiber to <3 aliens would definately be helpful.
It's important to distinguish between the SETI Insitute, an organization that does some SETI (but also does a lot of biology, geology, planetary science and bioastronomy), from SETI the discipline. Most people who do SETI do not work at the SETI Institute.
Support SETI@home
So using that as a basis for comparison, seti@home is consuming 1,432,500 watts per second.
No, it isn't--a "watt per second" is a nonsensical unit. The watt is already a rate of energy consumption, equal to a joule per second.
Based on data provided by the EPA (http://www.epa.gov/cleanenergy/energy-resources/refs.html ) which reports carbon output as 6.8956 x 10-4 metric tons CO2 / kWh, seti is producing 3,556 metric tons of CO2 per second!
No, no, no. A kWh (kilowatt hour) is an amount of energy equivalent to drawing one kilowatt (one thousand watts) continuously for one hour: one thousand joules per second, times 3600 seconds per hour, gives 3.6 million joules per hour in one kWh. For comparison, one kilowatt is the amount of electricity drawn by roughly fifteen incandescent light bulbs, or by one smallish toaster. The average U.S. household uses on the order of 1000 kWh per month.
Using your estimate of 1,432,500 watts - 1432.5 kilowatts, trivially equivalent to 1432.5 kWh per hour - for the power draw for SETI@home, we get a consumption of 0.398 kWh per second. Using your figure of 6.89E-4 tons CO2 / kWh, that comes to 0.000274 tons per second, or about 274 grams (a little over half a pound -not three thousand tons - per second). In total it comes to about a ton of CO2 per day.
That's not a negligible amount of CO2. It comes out to the equivalent of the electricity use of about a thousand U.S. homes. (Note that that doesn't include household CO2 contributions from other sources, particularly fossil fuels burned for home heating, water heating, clothes drying, and transportation.) But it's also not an egregiously large amount of electricity--the U.S. has, what, a hundred million households?
~Idarubicin
I am pretty sure gravity propagates at the speed of light. And we do have gravity wave detectors.
Your example says absolutely nothing about violation of causality due to a change in the maximum speed at which information can propagate. You are either describing a situation in which there is improper time coordination, or you are assuming time travelling signals to start with.
While there are no known methods by which information can propagate faster than light...
If something were to be discovered which could do this it would not necessarily violate causality, it would merely prove that relativity is either incorrect or incomplete (even if it were to allow instantaneous travel to any point in the universe, and the new maximum speed is therefore infinite.)
In order to violate causality you would need to be able to receive a message you sent before you sent it.
Instant propagation of information would likely allow a universal clock across all space, and you could coordinate time by that. You would need to adjust for the faster travel time if you are synchronizing your clock based on the speed of light, but it would be trivial to do that anyway.
Under relativity it is undefined what would happen if you could travel faster than light, as the theory does not allow this. It is basically not usable in this case, and trying to do so would be foolish (it simply does not cover what you want to do, and you obviously have information that Einstein did not when he came up with it if you are communicating FTL.)
If I could send this post beyond the edge of the known universe and back with zero travel time I still cannot read it before it is written, and causality remains very much intact.
The only thing that would change is that if you are three light hours away, I could get a message to you three hours before an electromagnetic signal would be capable of. We would be able to converse in real time instead of with the delay, nothing else.
If you could produce the post I just wrote before I wrote it, you would have a causality violation. No rate of travel allows this, no matter how large it is.
I am not sure why this is so hard for many people to understand.
I'm a signature virus. Please copy me to your signature so I can replicate.
I'm not going to check, but I think I've already replied to you elsewhere.
No, I'm afraid gravity propagates at C, which is the same as the maximum speed of light. If the Sun randomly vanished, no effect from that would reach us for 8 minutes- Earth would continue to orbit around the spot where the Sun had been for 8 minutes before the change in the gravitational field reached us. In Relativity, there are no cheats to get around C- it is the maximum speed for any form of matter, energy or information to travel, full stop.
http://en.wikipedia.org/wiki/Speed_of_gravity