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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 :)

Comment Paul Baran, RAND 1964; invented and "discovered" (Score 1) 257

It wasn't just Paul Baran, of course, but the main concepts were invented/discovered in his series of papers from RAND at a time before anyone else was talking about such a thing (late 50s, early 60s):

    Introduction to Distributed Communications Networks
        - http://www.rand.org/content/dam/rand/pubs/research_memoranda/2006/RM3420.pdf

    - distributed mesh network of cheap, heterogenous component parts (the topology is analytically derived as optimal for retaining connectivity after possible partition events), supporting wired and wireless links
    - mail-like asynchronous address/packet-based routing of
    - digitally encoded fixed sized data blocks (inspired by "Morse's code"))
    - adaptive topology based on flood-filling neighbor/connectivity information throughout the network.

This was shelved for 5-10 years for being thought a bad idea by the AT&T engineers that DoD listened to at the time (they were designing progressively more monolithic hierarchical networks with very expensive switching equipment requiring very profitable professional administration), and was picked back up in the later 60s, when it was ironed out and then re-invented by many of the names now famous for it:

Here's an excellent discussion about this between Baran and Stewart Brand:

    http://www.wired.com/wired/archive/9.03/baran_pr.html

Comment Trying to understand the paper's reasoning... (Score 1) 786

Here's my understanding of their reasoning.

Motivation:
        - Insolation changes and CO2 ecosystem feedbacks have been identified as the main causes of climate variability for the past million years (by citation).
        - However, global climate models are either too short to or don't attempt to integrate longer-term or low-frequency insolation changes, which might mean they're mis-estimating temperatures and temperature changes.
        - and while tree ring records should be affected and are important and widespread, a suitable long-term record that accounts for insolation changes hasn't been developed.
        - so, let's make one...

Methods:
        - measures tree ring width in Scandinavia for the past 2k years among ~580 trees, both living and dead.
        - fits a regression model between the tree ring width and "instrumental" measurements back to 1812, so that an observed tree ring width for a given year can be used to compute a temperature for that year, with some statistically measured error.
        - extrapolates temperatures before 1812 using the observed tree ring widths as inputs to the temperature regression model
        - derives a trend on these temperatures that shows a small, slow cooling for the past 2k years *in Scandinavia*.

Analysis:
        - notes that this slow downward trend/signature is missing from global published models
        - deduces that global temperature estimates for previous eras may then be *underestimated*, which implies that they could have been warmer and so today may not be as relatively warm as short-term models indicate.

However, they don't offer a reason how/why Scandinavian temperature trends should track global trends, or alternatively establish how/why orbital forcing should be accounted into global models? These both seem like reasonable expectations, and it seems the reasonable next step is to reproduce this project for other forrest areas to see if it holds.

Comment trying to understand methods & analysis (Score 1) 3

Here's my understanding of their reasoning.

Motivation:
    - Insolation changes and CO2 ecosystem feedbacks have been identified as the main causes of climate variability for the past million years.
    - However, global climate models are either too short or don't integrate low-frequency insolation changes, which might mean they're mis-estimating temperatures and temperature changes.
    - and while tree ring records are important and widespread, a suitable long-term record that accounts for insolation changes hasn't been developed.
    - so, let's make one!

Methods:
    - measures tree ring width in Scandinavia for 2k years among ~500 trees, both living and dead.
    - fits a regression model between the tree ring width and "instrumental" measurements back to 1812, so that an observed tree ring width for a given year can be used to compute a temperature for that year, with some statistically measured error.
    - extrapolates temperatures before 1812 using the observed tree ring widths as inputs to the temperature regression model
    - derives a trend on these temperatures that shows a small, slow cooling for the past 2k years *in Scandinavia*.

Analysis:
    - notes that this signature is missing from global published models
    - notes that global temperature estimates for previous eras may then be *underestimated*, which implies that they could have been warmer and so today may not be as relatively warm as short-term models indicate.

However, they don't offer a reason how/why Scandinavian temperature trends should track global trends, or alternatively establish how/why orbital forcing should be accounted into global models? These both seem like reasonable expectations, and it seems the reasonable next step is to reproduce this project for other forrest areas to see if it holds.

Comment Re:Electric Universe crackpots (Score 1) 95

They don't read like crackpots to me. Name-calling alternative perspectives is something more indicative of religion than science ;p Also, this is the interwebz; there are actual crackpots in abundance.

From their site:

"... theories tend to harden into ‘facts,’ even in the face of mounting
contradictions. Astronomer Carl Sagan’s Cosmos was published a
quarter-century ago. At that time, some questions were still permitted.
On the issue of redshift, Sagan wrote: “There is nevertheless a
nagging suspicion among some astronomers, that all may not be right
with the deduction, from the redshift of galaxies via the Doppler effect,
that the universe is expanding. The astronomer Halton Arp has found
enigmatic and disturbing cases where a galaxy and a quasar, or a pair
of galaxies, that are in apparent physical association have very
different redshifts....” - p 20. http://www.thunderbolts.info/EU%20Intro%20and%20Chap1.pdf

They're overall arguing that electrodynamics can better explain many astronomical observations than gravitation + dark matter, dark energy and modifications to cosmological constants.

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

Dark matter, dark energy, etc. are the first examples I give to friends who are skeptical of big bang cosmology or even science in general, showing it as an example of how science is full of bad "working" theories, but we know it and keep chipping away. I hope I'm not wrong.

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