Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×

Comment Re:More to the point... (Score 2) 437

No it is not impossible. The raft is made of basalt mostly and is somewhat less dense than the upper mantle, and is up to 35 KM thick. Although the bottom of the raft is quite hot - to the point of considerable plasticity - it conducts the heat from the Earth's deeper mantle through it well enough that it mostly maintains its integrity - and even where it is liquid it does not sink because it is of less density than the mantle it floats on and the heat is nowhere near enough to dissolve it in solution. Once upon a time of course Antarctica was part of a much larger raft. Offloading ice from the top of this raft not only increases the depth of the ocean - by eliminating the raft's displacement in the mantle the effect is actually doubled. In addition to the obvious ocean level effects this can have effects on plate tectonics, earthquakes and vulcanism all over the planet.

I know, it's normal to think of terra firma as some immutable rock dozens of miles thick but on this scale that's not the best way to think of it. It's more helpful to think of it as a very thin skin - relatively speaking far less than the thickness of an apple skin - made of lumpy rubbery stuff floating on a sticky gooey ball. The lumps are continents. The gooey inside has convection driven by heat - mostly nuclear fission - that moves the lumps around on the skin away from upwells and toward downsinks, eventually recycling almost the whole skin. This is why the oldest ocean floor material we can find is only 200Myrs old. The edges of the convection define tectonic plates. But the lumps are made of lighter stuff than the gooey center (mostly silica, the lumps) so the convection doesn't eat it all and when it does, can't keep it down for long. In the process the lighter elements bubble back up again eventually, and the captured iron and such from asteroid impacts settles into the core. Vulcanism, steam and air combine to make more lumps by making pockets of foamed rock that will float until they come to a downsink again.

It takes a long time but the processes are pretty well understood. When talking about a continent as large as Antarctica you have to think a lot bigger, use a wider scope of time. The raft that is Antarctica is moving in the general direction of the Atlantic Ocean at a rate of 10 km/My so in the span of time discussed here (5My) it has moved 50km. It moving into its current position has had dramatic climatic effects. If it moves far enough off the south pole then that will disrupt the circumpolar oceanic currents and the global climate will have a dramatic change again. It may not ever move off of the pole because of Coriolis forces before the question becomes irrelevant.

Now let's talk about that ice. Though we've plumbed the deepest ice we can find in Antarctica the oldest ice we can find is known to be less than 500Ky old. We know the snow has been falling and sticking there for many millions of years, so where did it go? The reason for this is obvious: the ice in Antarctica doesn't melt from the top down. It is never warm enough there to do that and hasn't been for 50 million years, climate notwithstanding. It melts from the bottom up, as the geothermal energy discussed above interacts with the ice layer from below. The ice is a grand insulator, so the energy from below melts the bottom of the ice. The water becomes a very thin layer around the edges of an extremely large bathtub completely overfilled with ice miles high, so it is expressed out on the edges even though it must travel uphill to do so. Like putting too much ice in an already filled cup. This is why atmospheric greenhouse gases are not ever, ever going to have an effect on Antarctic ice even if the average air temps at the pole soar 12C - and certainly not in the span of a few million years. The top of the ice doesn't melt and hasn't for many, many millions of years - since the time when Antarctica was in a more temperate latitude.

Now please be a bit more careful with that word "impossible".

Comment It is even simpler (Score 1) 258

An image file is nothing more the instructions to a graphics program of how to produce an image. It is the image that is copyrighted NOT the graphics file. That why re-encoding a file doesn't change its copyright. You might as well claim that the light emitting from your screen isn't the copyright image...

IF you want to challenge this, you should seek the "recipe" route. US copyright does NOT allow recipes that are mere listings of ingredients to be copyrighted. Is an image/CAD/MP3 file not merely a listing of inputs to the cook/graphics program/CAD/music player? Bit X tells the speaker magnet to move to position Y and foila, sound emerges same as if I combine eggs with milk and heat, an omelet comes out.

But this idea is nothing new, smarter people then me have thought about this AND come to the conclusion it doesn't work like this. A movie file is NOT a recipe for a light show on your monitor. It isn't the instructions that are copyrighted, it is the art. A CAD file for a simple ball is not copyrightable, a figurine is.

And this makes common sense because right now it is NOT allowed to scan a figure and reproduce it. So why should a CAD file, which could easily be produced by scanning not be copyrightable under existing laws?

I am not making a judgement here on right or wrong, I think the copyright system sucks BUT as it is now, 3D printing of other peoples creations falls under copyright infringement if they did not give you permission or made the designs open to all.

Comment Re:This is settled law, due to auto parts (Score 1) 258

using blueprints

The problem is that the CC doesn't cover all use, but reproduction, modification and redistribution. It's not a EULA; it expressly only restricts those uses that would also be restricted by copyright.

2. Fair Dealing Rights. Nothing in this License is intended to reduce, limit, or restrict any uses free from copyright or rights arising from limitations or exceptions that are provided for in connection with the copyright protection under copyright law or other applicable laws.

3. License Grant. Subject to the terms and conditions of this License, Licensor hereby grants You a worldwide, royalty-free, non-exclusive, perpetual (for the duration of the applicable copyright) license to exercise the rights in the Work as stated below:

        to Reproduce the Work, to incorporate the Work into one or more Collections, and to Reproduce the Work as incorporated in the Collections;
        to create and Reproduce Adaptations provided that any such Adaptation, including any translation in any medium, takes reasonable steps to clearly label, demarcate or otherwise identify that changes were made to the original Work. For example, a translation could be marked "The original work was translated from English to Spanish," or a modification could indicate "The original work has been modified.";
        to Distribute and Publicly Perform the Work including as incorporated in Collections; and,
        to Distribute and Publicly Perform Adaptations.
[...]
4. Restrictions. The license granted in Section 3 above is expressly made subject to and limited by the following restrictions:
[...]
You may not exercise any of the rights granted to You in Section 3 above in any manner that is primarily intended for or directed toward commercial advantage or private monetary compensation.

The question is whether the printed object is to be considered an inferior reproduction/adaptation of the blueprint (like a photocopied book) or just something that the blueprints happened to produce while you were using them (like the output of a program).

Comment Re:Who was burning fossil fuels then? (Score 1) 437

Obviously if an increase of 0.6C causes terrifying hurricane events, then at nearly 10x as much the entire surface of the Earth is regularly scoured of all life by rampaging sharknados and humans just can't exist. Not even in northern climes where an increase of 5C might barely move the average above freezing. Didn't you watch the documentaries?

Comment Reverse canary (Score 2) 309

The idea of explicitly stating that you aren't under a gag order has been addressed a few times, and I'm not sure it works - can you really not be forced to explicitly keep lying about it? After all, you'd have to lie in response to a direct question as well. Otherwise you could just tell your customers to regularly ask you about gag orders.

However, consider this: If you are not under a gag order, then it is not illegal to lie and say you are. (Except under oath.) Yet if you are under a gag order, saying you are would be illegal.
Thus, if you publically and untruthfully state (in messages or on your website) that you are under a gag order, then an actual gag order would force you to remove that statement. That removal then becomes the warning.

The gag order couldn't reasonably force you to tell people about it and not tell people about it.

Comment Re:Harder done than said (Score 1) 309

Well, they know who they sent the letter to, so they could trace it back by definition.

The only way to leak it and have a chance of avoiding the consequences might be to engineer some kind of plausible security breach. Briefcase with documents gets stolen/left on a train; network gets compromised, etc. Even so, if the timing is suspicious, you'd probably be in deep crap.

Slashdot Top Deals

Software production is assumed to be a line function, but it is run like a staff function. -- Paul Licker

Working...