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Comment There's an interesting trend here (Score 1) 233

Compare to Terrence Deacon's Incomplete Nature, which: "meticulously traces the emergence of this special causal capacity from simple thermodynamics to self-organizing dynamics to living and mental dynamics" (Amazon).

(Deacon's book is good, though has been criticized as drawing heavily from prior work: "This work has attracted controversy, as reviewers[2] have suggested that many of the ideas in it were first published by Alicia Juarrero in Dynamics of Action (1999, MIT Press) and by Evan Thompson in Mind in Life (2007, Belknap Press and Harvard University Press) yet these works were not cited or referenced by Deacon." (Wikipedia))

Or compare to Stuart Kauffman's Origins of Order, which Deacon cites (and it seems the two are in communication). Kauffman's notion is that there are implicit geometries to energetic forms which in the situation of excess total energy can locally channel a system towards structure and shape that bias, and perhaps belie, the notions of random variation and natural selection being the primary drivers for the creation of structures in living beings.

Neat to see this coming to the east coast/MIT.

Comment Old enough for galactic panspermia? (Score 1) 272

Article says predecessors may have evolved around the predecessor star to our Sun, but given the time spans involved why just our sun? If early bacteria were ejected into space by vulcanism, solar wind would accelerate them outwards to ~400km/s, or about .1% speed of light. At that speed, you could cross the galaxy in a scant 100 million years.

Depends on what happens to low-weight particles at the heliopause though, especially if they've become ionized during travel.

Comment Maximum Wage & Maximum Wealth (Score 2) 1106

http://en.wikipedia.org/wiki/File:U.S._Distribution_of_Wealth,_2007.jpg

Imagine a banquet for 100 people where everyone brought their produce from a day of work in their home gardens and farms, 2000 calories worth each, and then divvied up the food like this:

    40 people were given a single slice of apple and water
    20 people were given a serving of ham and potatoes, so 60 had been served
    20 people were given a salad topped with blue cheese and vinaigrette and then salmon on rice with a side of broccoli, so 80 had been served.
    10 people were given a large meal, with nuts and breads to start, then a salad, a couple of appetizers each, a large steak with potatoes on the side, a desert and cappuccino, and multiple glasses of wine throughout, so 90 had been served
    5 people were given a dinner that they simply couldn't finish.. like the last one, but with 90 oz T-bone steak, a whole plate of mashed potatoes, a spread of fruits and cheeses and 2 or 3 deserts, so 95 had been served
    4 people were given a full week's set of these really surpassing, 7-course meals, all arrayed nicely in front of them in a building crescendo of delights for the next 7 days, so that 99 had been served
    And the last person, was given a month of these 7-course meals and it was not clear even how to get them back home.

So everyone had been served. Now imagine what these people talk about at dinner. Perhaps something like this?

    "It's not fair that 40 people just got a slice of apple! Did you see those slices?! They're puny. We should give them a bigger slice of apple!"

Sigh. At least talk about Maximum wage instead of Minimum wage:

    http://en.wikipedia.org/wiki/Maximum_wage

But then, if you really want to build a nice community to live in for the long-term (remember, wage is not the only way to accumulate wealth), talk about maximum wealth; no wiki about this yet though ;)

Comment Re:Roman Empire (Score 1) 627

That's not really what the author claims, rather that the skeletons she has looked at do support it, but can't just be supposed to be representative of the whole population.

"The Imperial period [in Rome] is pretty special - we've got people with lead levels up to 30 mg/kg, which is 30 times higher than modern recommendations! In fact, this level is three times higher than the level the WHO considers "very severe lead poisoning."" ...

"Did lead poisoning cause the fall of the Roman Empire? Probably not. Yes, there was increased lead production in the Roman Empire, which we know from histories, ecological sources (like ice cores from Greenland and peat bogs in Europe), artifacts, and now skeletons. But the data - few as they are - simply don't support a conclusion of high lead concentration in the entire population."

Comment Appeal bad analysis of GPS mechanism and pinging (Score 1) 312

Judge John Rogers, in his ruling, says multiple times that the phone was emanating information that the authorities tracked, therefore no invasion of privacy. He compares it to the scent a dog uses to follow someone, or the color of a car, or the numbers on a license plate, or the location of a car when it is on a public road.

"The government used data emanating from Melvin Skinner’s pay-as-you-go cell phone to determine its real-time location." (http://www.ca6.uscourts.gov/opinions.pdf/12a0262p-06.pdf, p2, par1)

Rogers says the information the phone was emanating was just a "proxy" to this other publicly visible information. It's not clear what this "proxy" status is for the phone, but more importantly, the GPS in the phone could not have been emanating position information because that's not how client stations work in GPS. The satellites in the sky emanate position information, and the ground units just receive this and triangulate position from it. Otherwise, it would be a terrible technology for the military to use, as they would be easily located!

The judgement acknowledges that "ping" data had to be accessed from phone company, and that "pinging" the phone is an activity engaged in by the DEA agents on the suspect's phone, but somehow sticks with the emanating logic: "a federal magistrate judge, on July 12, 2006, authoriz[ed] the phone company to release subscriber information, cell site information, GPS real-time location, and “ping” data for the 6447 phone in order to learn Big Foot’s location while he was en route to deliver the drugs." (p4, par1)

(By pining the first phone and realizing it was at Big Foot's home, and not on the road with him, the DEA agents got another "authorization" for the release of the same data for a second "6820" phone.)

"By continuously “pinging” the 6820 phone, authorities learned that Big Foot left Tucson, Arizona on Friday, July 14, 2006, and was traveling on Interstate 40 across Texas. At no point did agents follow the vehicle or conduct any type of visual surveillance. At around 2:00 a.m. on Sunday, July 16, 2006, the GPS indicated that the 6820 phone had stopped somewhere near Abilene, Texas." (p4, par3)

That's where they moved in, did a K-9 walk-around of the RV, and then arrested him.

In the judgement about the 4th Amendment violation:

"If a tool used to transport contraband gives off a signal that can be tracked for location, certainly the police can track the signal."

Of course, GPS clients like the suspect's phone do not actually give of a position signal, which is why they had to ping it. Rogers' logic is most carefully stated in the following, and so perhaps this could be the grounds for a new appeal:

"This case is different from the recent Supreme Court decision in United States
v. Jones, 132 S. Ct. 945 (2012). That case involved the secret placement of a tracking
device on the defendant’s car, id. at 948, and the Court’s opinion explicitly relied on the
trespassory nature of the police action. Id. at 949. Although Fourth Amendment
jurisprudence includes an assessment of the defendant’s reasonable expectation of
privacy, that “d[oes] not erode the principle ‘that, when the Government does engage in
physical intrusion of a constitutionally protected area in order to obtain information, that
intrusion may constitute a violation of the Fourth Amendment.’” Id. at 951 (quoting
Knotts, 460 U.S. at 286 (Brennan, J., concurring)). No such physical intrusion occurred
in Skinner’s case. Skinner himself obtained the cell phone for the purpose of
communication, and that phone included the GPS technology used to track the phone’s
whereabouts. The majority in Jones based its decision on the fact that the police had to
“physically occup[y] private property for the purpose of obtaining information.”
132 S. Ct. at 949. That did not occur in this case." (p10, par2)

This decision relies on a faulty understanding that GPS emanates a signal that the agents passively received, while paradoxically also admitting earlier that the unit was "pinged" to determine its location. Somehow, the use of the term "ping" elides what should have been a more thorough analysis, which could only have shown that pinging the device is physically interacting with (or physically occupying?) the suspect's private property to obtain information from it that would not otherwise be available to the public.

Comment Re:Chaos... what? (Score 1) 74

So, I think the solution process for an arbitrary system of simultaneous equations actually has a *propensity* to lead to deterministic chaos. I was just looking for a paper discussing this, but came up short; but for the background see:

    http://en.wikipedia.org/wiki/Iterated_function_system

Note, the way I'm interpreting this is that *solving* the system leads to iteration of candidate systems in your head, therefore there's an (hypothetical) expected chaotic dynamic. (haven't rtfa yet.. :)

Is there something about the way sudoku systems are chosen, e.g. they're too simple, that excludes this?

Comment Metallic hydrogen (Score 1) 1

Here's an interesting article:

    http://en.wikipedia.org/wiki/Metallic_hydrogen#Metallization_of_hydrogen_in_shock-wave_compression

Especially the discussion of the LLNL shock-wave compression. Metallic indeed :)

3000K is not too far from the temperature of the surface of the Sun, and the pressures are thought to vary from virtually nothing at the surface to Peta-pascals in the core, so somewhere there's a transition by the 140GPa needed for metallization. Whether this is within the convective layers where the temperatures remain low..?

User Journal

Journal Journal: Metallic sun 1

I'm posting this for follow-up commentary from @APODNereid, since the thread is now closed.

http://slashdot.org/comments.pl?sid=2967801&cid=40758811

You ask what would keep the surface metallic. Thinking about this more, I found a couple of facts:

The Sun's surface has an energy flux density ~30x that of a hot metal rod at 3,000 C (around the glow point for tungsten in a lightbulb) in the experiment described here:

Comment Re:Electric Universe crackpots (Score 1) 95

Hm, I think you're missing my point... I wasn't supporting their claims as more correct than a gravitationally-based cosmology, just noting that they seemed to be making reasonable conjectures, albeit non-mainstream, and that they didn't deserve to be called names. I said:

    "That seems reasonable; correct or not is a matter to be determined."

The same can be said about dark energy/matter. Reasonable, but correctness TBD. It is problematic for a simulation to not model all know behaviors of a system, but nonetheless, we do it all the time and often find useful models in them.

Agreed, this is better termed Plasma Cosmology, not Electric Universe as that appears to be commercially co-opted; maybe you're reacting more to that; I was reading more of the folks they cited than the .info website. More:

http://en.wikipedia.org/wiki/Plasma_cosmology#Large_scale_structure

Comment Re:Electric Universe crackpots (Score 1) 95

The one I looked at most closely was in the intro chapter to one of the books they linked:

http://www.thunderbolts.info/EU%20Intro%20and%20Chap1.pdf

That the shapes and spins of galaxies can be shown in simulation by collapsing parallel electric filaments ("pinch" effect), p. 26.. In contrast, from what I understand, you have to introduce a majority of dark matter & energy into such a simulation to get a stable galaxy if the stars interact otherwise with only gravity.

Something I'm looking at that's related to this:

http://en.wikipedia.org/wiki/Millennium_Run

It runs an N-body particle solver using gravitational interactions, to run the cosmic microwave background "forward" to see what kind of modern universe it should develop. This produces the pictures of the filamentary large-scale structure of the universe that I've become accustomed to seeing in recent years, but it turns out you can use the same software to model both radiative and magnetic coupling effects. Here's a variation showing how radiation changes stellar evolution:

    http://www.astro.ex.ac.uk/people/mbate/Cluster/clusterRT.html

Same basic large-scale structure, but different number of "stars", different brightnesses, speeds, etc.

I've got the GADGET code running on my MacBook Air using MacPorts, etc.. should be fun, though very slow :)

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