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Tim Cook Says Apple Can't Read Users' Emails, That iCloud Wasn't Hacked

Garfong Re:Is this technically impossible - no. (190 comments)

Fair enough. As I said, I suspected this was not actually what Apple was doing.

I was responding to GGP claim that services like Lavabit were logically impossible, which clearly isn't true: Lavabit existed. But as you say, Apple is obviously not doing the same level of encryption.

3 days ago
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Tim Cook Says Apple Can't Read Users' Emails, That iCloud Wasn't Hacked

Garfong Re:Is this technically impossible - no. (190 comments)

I can read my mail, so can he. It's only logical.

Not true. They could be encrypting your emails with a public key as soon as the email hits their server, and have the private key encrypted based on your password. Then you could only access at most the email of users who were currently logged in.

But I think it's more likely that they don't have any tools to read user's emails, but they're still stored on the server essentially in the clear.

3 days ago
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If Tesla Can Run Its Gigafactory On 100% Renewables, Why Can't Others?

Garfong Re:Renew this! (444 comments)

You're probably right -- I do need to review my thermo. University was many years ago, and thermo was taught in a hot class room in the middle of summer by a prof who was in his 60s and coasting to retirement. But I meant to claim that lithium battery chemistry was thermodynamically reversible _in theory_, whereas a heat engine (such as a gasoline engine) is not. Although I'm not really sure if this is true either, but practical efficiencies are in the 90% range (according to the sources cited by wikipedia), which includes internal impedances, and other real-world losses. So it seems likely to either be theoretically thermodynamically reversible, or very close.

But you were the one who said the hydrocarbons were being burned (in your previous post). In this case, lithium battery discharge/recharge cycle is up to ~90% efficient, whereas gasoline burning has an average efficiency of 25-35%. So ignoring the efficiency of the hypothetical gasoline recovery process, that's a difference of at least 55%.

I think it's ironic that you consider a difference between 100% and 90% completely invalidates what I'm saying, but me pointing out a difference between 90% and 35% is being pedantic.

4 days ago
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If Tesla Can Run Its Gigafactory On 100% Renewables, Why Can't Others?

Garfong Re:Renew this! (444 comments)

Recharging lithium batteries and recovering hydrocarbons from exhaust waste are not equivalent. Lithium battery discharge is a reversible process, so the original state can be recovered by input of the same amount of energy as was originally extracted from the system. Gasoline & turbine engines (like all heat engines) are non-reversible, which means it takes more energy to recover the initial state than was extracted as useful work. This is because only a portion of the energy produced by burning hydrocarbons can be extracted as work -- the rest escapes as heat.

about a week ago
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German Court: Google Must Stop Ignoring Customer E-mails

Garfong Re:define "customer" (290 comments)

I don't know if this applies here, but from what I hear contract law is very different in Germany. The example I've heard is when you buy something from a store in a common-law country, there's an implied contract for sale of the goods. In Germany, apparently there's about three implied contracts.

about a week ago
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Universal Big Bang Lithium Deficit Confirmed

Garfong Re:Quite accurately? (170 comments)

Then it would show up as extra energy.

about a week ago
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Universal Big Bang Lithium Deficit Confirmed

Garfong Re:Quite accurately? (170 comments)

1. With a BA in physics (mid-90's), I was taught about the Big Bang and elements calculation multiple times. In every single instance I was shown the calculated and observed percentages, and they were always given as a good match, as part of the proof. I'm really confused that now it's been known for decades that they *don't* match. Were my books lying to me? Was this observation adjusted the year I graduated college, and I just missed the controversy?

It's possible that for the version of the model you were given, order of magnitude was considered a "good match". I still remember my prof leading our class through a calculation of heat capacity of copper using quantum mechanics, and getting a value which was off by about this much, and it was considered a "good match" because given all the simplifications needed, even getting something in the right neighborhood seen as confirmation of the overall approach.

Also, according to Wikipedia, measurements of the cosmic microwave background radiation within the last 15 years have fixed some of the parameters of Big Bang nucleosynthesis, so it's possible what was considered a minor discrepancy which may be explained by future research has become a discrepancy which has been highlighted by recent research.

2. I'm also really curious to hear which elements have a *higher* concentration, to make up for the missing lithium. If we were just short a bunch of lithium, all of the other elements would be higher, percentage wise, and thus all of them would be off. Since the others are spot-on, I've got to think there's at least one element out there that's disproportionately high to balance it out.

Not necessarily. From what I remember, Hydrogen and Helium are so much more abundant in the universe than Lithium, that a 3x difference in Lithium concentration could easily be 1% or less in H or He concentrations.

about a week ago
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Ask Slashdot: What Smartwatch Apps Could You See Yourself Using?

Garfong Betteridge's law of headlines (471 comments)

What smartwatch apps could I see myself using? No.

Which is actually the closest answer I can give to this question -- I can't see myself owning a smartwatch.

about two weeks ago
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Out of the Warehouse: Climate Researchers Rescue Long-Lost Satellite Images

Garfong Re:Straight to the pointless debate (136 comments)

Or another way of thinking of it is you're using the measured data to estimate a hidden variable which is what you're really interested in. E.g. in this case you have a number of measurements near cities, and you're trying to estimate the global/wide-area average temperature. So you apply a correction to get from city temperature to an estimate of the wide-area average temperature.

(This is mostly in response to GP).

about two weeks ago
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NASA's Greenhouse Gas Observatory Captures 'First Light'

Garfong Re:How is CO2 leading cause of warming? (143 comments)

The ability to accurately model the details of a system is usually not required to model the average, long term, behaviour of the system.

Rolling dice is a complex chaotic system. Yet despite my complete inability to predict the results of any roll, I'm confident that casinos will make money on craps tables.

about a month ago
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Hack an Oscilloscope, Get a DMCA Take-Down Notice From Tektronix

Garfong Re:A comment from the linked site: (273 comments)

Many oscilloscopes are Windows PCs with signal acquisition cards and special software, in an oscilloscope case. So the theory is probably that the pre-loaded oscilloscope software is the "protected work".

about a month and a half ago
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US Army To Transport American Ebola Victim To Atlanta Hospital From Liberia

Garfong Re:NIMBY at its finest (409 comments)

My guess is that at least part of this trip is due to the Democrats not wanting to have to explain to the electorate why they let two of God's Favorites expire in some sweaty jungle hut.

Because that's never happened before.

about a month and a half ago
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US Army To Transport American Ebola Victim To Atlanta Hospital From Liberia

Garfong Re:NIMBY at its finest (409 comments)

If I thought that generating papers had no bearing on choice of research, I would have said that. Since that's not what I said, please don't assume that's secretly what I meant.

But (ideally) high quality papers will come from high quality research. I think you're doing a huge disservice to the doctor who has a 60-90% chance of dying, and the researchers working with him. If all they cared about was their tenure review and grant cycles, they could probably find some research that had 100% less chance of dying of a strange African disease.

about a month and a half ago
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US Army To Transport American Ebola Victim To Atlanta Hospital From Liberia

Garfong Re:NIMBY at its finest (409 comments)

Right. Because the purpose of research is to generate papers.

Kind of like the purpose of falling in love is to get a marriage certificate.

about a month and a half ago
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Tesla and Panasonic Have Reached an Agreement On the Gigafactory

Garfong Re:What makes this a gigafactory? (95 comments)

Given Tesla's eco-friendly marking, this would probably be a bonus for a TeraFactory.

about 2 months ago
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Senate Bill Would Ban Most Bulk Surveillance

Garfong Who does the NSA report to? (176 comments)

Don't the NSA report, directly or indirectly, to the President? So if executive branch support a measure to limit bulk surveillance, couldn't they, of their own initiative, direct the appropriate agencies to cancel or modify the mass surveillance programs?

about 2 months ago
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Laser Eye Surgery, Revisited 10 Years Later

Garfong Re:Cost (550 comments)

At least where I live, prescription glasses are tax-free medical devices; ironic glasses are taxed fashion accessories.

Of course the tax is far less than the cost of prescription lenses, but if you're going to wear glasses anyway the government is literally subsidizing not getting Lasik.

about 2 months ago
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Google To Stop Describing Games With In-App Purchases As 'Free'

Garfong Re:Good. Now what about ads? (139 comments)

I don't want it all for free, but I think companies should be honest about their business model. I think they should distinguish between "Free" trial, "Free" with paid upgrades, "Free" ad-supported, etc.

about 2 months ago
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Sexual Harassment Is Common In Scientific Fieldwork

Garfong Re:Such harassment (362 comments)

Is it repeated, unwanted, attention of a sexual nature? Then it's sexual harassment.

about 2 months ago

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