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Comment The real news item (Score 2, Insightful) 343

is that a commercial entity is ponying up half the cost for something that could/should be handled by the government. From TFA:

"This project is a mobility improvement for the area as a whole," said Lou Gellos, a spokesman for Microsoft. An existing bridge a few blocks away is congested and a nightmare for pedestrians and bicycle riders, he said.

So, we have the relatively common phenomenon that commercial development has outgrown the infrastructure. Big deal. Usually the government handles this as part of its own work, without direct commercial assistance. In this case, MSFT is offering money to help solve the problem. They deserve kudos, not punishment, since they could alternatively be lobbying/strongarming the relevant government entities to foot the bill at 100%.

Even if you hold the (inane) view that MSFT should foot the bill at 100%, they don't have the authority to just build a bridge over any highway they want. So you need some kind of legislation anyway.

Comment Re:FTA "As measured in Earth's time frame" (Score 1) 184

You make a good point, but it's worth getting even more brain-twisting.

Assuming Einstein is correct about the speed of light c being an absolute speed limit, it literally doesn't make sense to talk about events "occurring" X years ago in a location greater than X light-years away. Since there is literally nothing we can do to observe later events from that location any faster than they are already arriving - i.e. no faster than light space travel - then those events may as well not have happened yet for our location. There's no way to "get behind" the wave of events to get an advance preview of what's coming next for our original location. There is no way for objects or information to travel faster than c, and the implications are profound.

Suppose we are X light years away from a star, and we see the light/events from it just as it goes supernova. Suppose we want to know what's happening with the blast wave coming in our direction, to see if there's something we can do to protect ourselves. (In Larry Niven's Ringworld the ring's ancient inhabitants apparently created the ringworld as an edge-on shield for exactly this purpose.)

We might start by thinking we can shoot a rocket with people/sensors on it really fast toward the star, get some information, and then come back so we can plan our defenses. The problem is that we can only travel up to the speed of light; so even though the people on the rocket are seeing the subsequent events "before" the people on earth, they can't send the information back any sooner than it was already going to arrive there.

Put another way - suppose there's a star 100 light-years away and a rocket 50 light-years away between us and the star. As soon as it detects the star going nova, the rocket zooms back home to warn us. Unfortunately, even with near-infinite acceleration it could only get back to us just at the same time that we see the nova for ourselves (since both the rocket and the original signal are traveling at/near c). As far as we're concerned, the rocket "saw" the nova at the same time we did. This is borne out by the experience of the rocket's crewmembers, who experienced little/no aging or time lapse between the moment they saw the nova and the moment they arrived back at earth (due to the near-infinite acceleration).

BTW I put "before" in quotes above because, by the same principles, there is no external observer who could time-correlate the observations at the rocket and at earth to establish ordering. This is the brain-bending consequence of unifying space and time...

- B

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