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Comment: Re:Not really needed (Score 1) 34

by Waffle Iron (#49349923) Attached to: MIT Debuts Integer Overflow Debugger

If his garbage causes you take take a different flow of execution, however, that provides him a way to reach bugs in the little-used parts of your code.

The different flow of execution triggered by an overflow trap should almost always be a simple call to "abort()". At this point, your program has already failed and should be stopped.

I disagree with your premise. Garbage input values should be checked and rejected in software before the overflow ever occurs. The hardware overflow check should be a last resort to enforce this at every instruction step, and in the worst case it converts privilege exploits into less serious DOS attacks.

Allowing "garbage output" as you propose just creates more opportunities for attacks when that output gets consumed somewhere.

Comment: Re:Competing with government-sanctioned monopolies (Score 1) 184

I'd like to invest in your fascinating scheme to sink $Trillions into needlessly duplicating infrastructure. Your concept of buying new 5X cost buried cables to compete with existing overhead wires just brilliant as well. Are you offering stock yet?

Comment: Keep it as is (Score 2, Insightful) 277

by Waffle Iron (#49204521) Attached to: Daylight Saving Time Change On Sunday For N. America

DST is not a bad idea. Who the hell is going to wake up at 4:00 a.m. in June? Who is going to do anything enjoyable or productive in the wee hours of the morning when they've still got a looming commute to work?

Stop all the damned whining and enjoy the sunlight while you're actually awake.

Comment: Re:Oh? (Score 1) 139

by Waffle Iron (#49137343) Attached to: 12-Billion-Solar-Mass Black Hole Discovered

If the matter is just "falling in" given the matter's density and distribution being less than 100% of the total possible space I think it's possible that your "maximum possible rate" is an artifact of a static model of a black hole at any given time. I think it's probably impossible that this rate was even approached, really, for any significant time period, certainly not "nearly its entire existence."

The amount of matter that fits in a given space is totally dependent on its pressure and temperature. For the conditions in an accretion disk near the surface of a black hole accumulating at its maximum rate, the space is at 100% of its capacity to hold matter.

Comment: Re:Oh? (Score 4, Interesting) 139

by Waffle Iron (#49137009) Attached to: 12-Billion-Solar-Mass Black Hole Discovered

"it must have been munching matter at close to the maximum physically possible rate"

That "maximum possible rate" sure sounds like bullshit.

Why does it sound like BS? Given that a huge fraction of the matter spiraling into the black hole is converted into energy before it falls in, that creates an outward pressure that limits how much more matter can follow. So there is a maximum rate that the black hole can accumulate mass.

Comment: Re:Gamma burst (Score 1) 203

by Waffle Iron (#49136675) Attached to: What Happens When Betelgeuse Explodes?

If you were to actually read some of the "literature", you would find out that your supposition is wrong. For example:

A GRB within a few parsecs that is directed at the Earth will impact one
hemisphere of the planet with a short, but intense blast of high energy
photons. Gamma rays and X rays are highly attenuated by the Earth’s atmosphere.
Therefore, the ground level effects are primarily indirect. A small fraction
of the incident energy reaches the ground as dangerous ultraviolet (UV)
radiation (Smith et al. 2004), but this is limited in time to the duration of
the event, which is at most 10’s of seconds for a long burst, and is less than
a seconds for a short burst. While it is possible that this flash would affect
some organisms, it seems unlikely that a biological catastrophe would result
from this effect alone. Of course, for planets with thinner atmospheres the
energy deposited at the ground would be greater and more serious effects may be
expected (Smith et al. 2004; Ga lante & Horvath 2007). We are concerned here
with effects on life on Earth and so will concentrate on the longer term

There are three potentially harmful long term effects of a GRB that follow from
changes in atmospheric chemistry (Reid & McAfee 1978). High energy photons
cause dissociation, GRBs and Life on Earth ionization and ionizing
dissociations of N and O in the atmosphere. Subsequent reactions lead to the
formation of nitrogen oxides, most importantly NO and NO These compounds
catalytically deplete ozone (O3) in the stratosphere, leading to increases in
surface level solar UV over long time periods (years). Secondly, NO2 itself is
a brown gas that absorbs strongly in the visible. This may potentially have a
climatic effect by reducing solar insolation a t the ground, thereby leading to
cooling. Third, the atmosphere returns to normal via the removal of nitrogen
oxides by way of precipitation of nitric acid (HNO3).

What's more, it's not possible to "wipe out life on earth" in this manner given that some organisms have been found living in rocks a couple of miles down inside the earth. Instead, a mass extinction is the worst case outcome.

Comment: Re:Gamma burst (Score 1) 203

by Waffle Iron (#49127957) Attached to: What Happens When Betelgeuse Explodes?

No, the atmosphere would shield you from the gamma rays. However, a side effect of that would be the generation of massive amounts of ozone-destroying chemicals in the upper atmosphere. The subsequent lack of ozone and massive UV exposure would be the real risk, especially because almost all of our food grows in sunlight.

"Be *excellent* to each other." -- Bill, or Ted, in Bill and Ted's Excellent Adventure