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Comment: Re:I agree. (Score 1) 122

by tlambert (#49183217) Attached to: Physicists Gear Up To Catch a Gravitational Wave

Assuming gravity propagates at the speed of light as a force, rather than being an artifact of space-time, which would mean you don't get any waves. Which we've so far not been able to detect, probably because they don't exist. 8-).

Except for still having to explain the orbital decay of complex objects matching predictions based on GR involving loss of energy due to gravity waves and gravity traveling at the speed of light.

And you don't need a tetrahedron of space craft, just three space craft to confirm or deny the quadrupole nature of gravity waves.

It's a fun gedanken experiment, but I'm not sure the Lisa Pathfinder will be successful; the quadrupole formula requires that the plane of polarization be distinct, and that the orbit be an ellipse. The Lisa experiment has some fundamental assumptions about a collision being the wave source, rather than an orbital source.

It'd totally be a bummer to spend all that money and not see anything because the detector happens to be in a 2D plane coinciding with a detectable event, and the lack of additional planes made it invisible.

Personally, I have to believe that we have a fundamental misunderstanding of something, because we otherwise should have seen them in one of our existing detectors, if they were there to be seen. I don't think the longer baseline Lisa gives us is going to help detect something that we are fundamentally getting wrong somehow.

I used to joke with some of my friends that there's be two great reasons Michelson-Morely might not have shown anything:

(1) The reference frame is sufficiently pinned by the gravity well of the Earth that we don't see any drift through the "luminiferous aether" because we are frame-dragging at a higher degree than the equipment is capable of distinguishing.

(2) The Earth *really is the center of the Universe*, so also: no drift relative to the universe's inertial frame.

It may be that we won't see gravity waves (if any exist) until we get a device pretty far out into interstellar space.

Comment: Re:Yahoo! (Score 1) 103

If Google doesn't want me to be found, then nobody who uses Google will find me on the net.

I shall put a big "Use Yahoo! if you want to find my website" banner on my webstore, that will teach them with their 97% market share!

Alternately... your site could be more relevant, then it would have a higher ranking.

Comment: Re:Yes? (Score 1) 103

The problem he mentioned was that actual phone operators are for example required to build all kind of gouvernment required bells and whistles into their network (emergency calls, independant power supply, wiretapping access...) while Skype et.al. don't have to spend that money and therefore can undercut them.

Apparently, you are unaware that German police are already tapping Skype calls...

http://www.pcworld.com/article...

Comment: Re:Yeah.... (Score 1) 103

It's arbitrary as far as an individual business is concerned, and that business doesn't necessarily have any control, insight or predictive ability over why it happens.

Sure they do. They can hire an SEO company to link-farm them, and then Google will shut their ass down, like they did to JC Penney.

http://fortune.com/2011/02/14/...

It's absolutely, totally, a negative control knob, but if some dumbass wants to turn that knob, they surely can. And the result is totally and completely predictable.

Comment: I agree. (Score 2, Interesting) 122

by tlambert (#49178103) Attached to: Physicists Gear Up To Catch a Gravitational Wave

That being said I fully expect gravitational waves to be discovered.

I am not so sure. There have been other experiments that should have detected them, but didn't. If this experiment also comes up empty, then physics may be facing another Michelson–Morley moment.

I agree. Gravity waves are unlikely. In theory, we can test the idea with a direct experiment, but the cost would be in the multiple billions, and require spacecraft to loft a tetrahedral constellation of some very large masses, and then you'd have to fling another large mass at an appreciable fraction of the speed of light, probably via solar slingshot, and (effectively) have it "instantaneously appear" intersecting a non-orthogonal plane vector through the tetrahedral constellation. That'd basically give you a wave delta that you could see based on laser interferometry along the vertices of the tetrahedron.

Assuming gravity propagates at the speed of light as a force, rather than being an artifact of space-time, which would mean you don't get any waves. Which we've so far not been able to detect, probably because they don't exist. 8-).

Comment: Re:In related news... (Score 1) 301

I don't think you understand the problem. They only get paid while on duty. So they drive from San Francisco to San Jose, let's say 2 hours from start to finish, then you're "off duty" but miles away from you home for at least 8 hours then you get to drive back for 2 hours. During those 8 hours you're essentially a hostage to being near that bus.

I think I would likely keep a car at the parking plaza where the bus ends up sitting. Probably one with a pink mustache.

As far as the Google busses, they basically round trip all day, every day, or when they cycle out, they park at shoreline Amphitheater. The drivers definitely do not "hang out" with the busses, which you can verify just by walking down there. Typically they dead-head back up to wherever by catching a ride on one of the less populated intermediate busses. I know at least one of them has a day job at the Great Mall, and only drives the bus to make some extra cash.

Apple is similar to Google with regard to their busses, but they tend to take charters in the mean time to keep busy.

As far as Facebook is concerned... I haven't worked there, like I have at Apple and Google, so yeah, they might be screwing over the bus drivers, but I think they are likely in exactly the same position that the Apple and Google drivers are in.

Comment: Re:Viewing Launches (Score 1) 22

by Bruce Perens (#49166815) Attached to: SpaceX Falcon 9 Launches Dual Satellite Mission

With luck, they'll start incorporating our radio transceivers. I hear that SpaceX flies with several USRPs now, so that's not completely unrealistic. That might be as close as I can get. Anyone who can get me a base invitation, though, would be greatly appreciated and I'd be happy to do some entertaining speeches while there. I need a base invite for Vandenberg, too. I got in to the official viewing site for the first try of the last launch (and that scrubbed too), but this next one is on Pad 6.

Comment: Viewing Launches (Score 3, Interesting) 22

by Bruce Perens (#49164783) Attached to: SpaceX Falcon 9 Launches Dual Satellite Mission

I was in Florida to speak at Orlando Hamcation and went to see the DISCOVR launch at Kennedy Space Center. I paid $50 to be at LC-39 for the launch, an observation tower made from a disused gantry on the Nasa Causeway between the pads and the Vehicle Assembly Building. A crawler was parked next door! A hot sandwich buffet, chips, and sodas were served. It was cold and windy! I watched for a few hours and unfortunately the launch scrubbed due to high stratospheric winds.

The next day, Delaware North Corporation, which operates tourism at KSC, decided not to open LC-39 or the Saturn 5 center for the launch. This was the third launch attempt and I guess they decided most people had left. I was annoyed.

The closest beach was going to be closed in the evening, it's a sensitive ecological area. I ended up seeing the launch from Jetty Park. This turned out not to be such a great location, the tower wasn't visible at all and the first 10 seconds of the rocket in flight were obscured before we saw it over a hill.

What's a better viewing location?

Comment: Re:How it's done: Link to SpritesMods.com article. (Score 2) 321

by Smallpond (#49158309) Attached to: Ask Slashdot: How Does One Verify Hard Drive Firmware?

That's a great article. So to answer the question in the summary, the way to verify your firmware is:

        Buy an identical replacement drive
        Use the vendor tool to install the same firmware version
        Use the tool described in the article to read the firmware from each drive over JTAG
        Compare the two copies to see if the suspect drive has been modified.

Comment: Re: stop the pseudo-scientific bullshit (Score 1) 88

by jd (#49156217) Attached to: Mysterious Siberian Crater Is Just One of Many

The Great Extinction, caused by Siberia becoming one gigantic lava bed (probably after an asteroid strike), was a bit further back in time. Geologically, Siberia is old. You might be confusing the vestiges of Ice Age dessication (which was 10,000 years ago) but which involves the organics on the surface with the geology (aka rocks).

Regardless, though, of how the craters are forming, the fact remains that an awful lot of greenhouse gas is being pumped into the air, an awful lot of information on early civilization is being blasted out of existence, and a lot of locals are finding that the land has suddenly become deadly.

To be a kind of moral Unix, he touched the hem of Nature's shift. -- Shelley

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