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Comment: Re:"The Polar Bears will be fine" (Score 4, Insightful) 372

by by (1706743) (#49634573) Attached to: Global Carbon Dioxide Levels Reach New Monthly Record

Dyson agrees that anthropogenic global warming exists, and has written that "[one] of the main causes of warming is the increase of carbon dioxide in the atmosphere resulting from our burning of fossil fuels such as oil and coal and natural gas."[53] However, he believes that existing simulation models of climate fail to account for some important factors, and hence the results will contain too much error to reliably predict future trends: ...

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

Freeman Dyson also doesn't understand gravity (no one does). But that doesn't mean some vague claims can't be made about the two -- "heavy objects hurt when they fall on your foot" isn't a rigorous scientific statement, but it is true, as is his (vague) quote above.

Comment: Re:how much it took (Score 1) 274

by by (1706743) (#49199445) Attached to: Laser Takes Out Truck Engine From a Mile Away

... the longer it takes the less practical it would be to use it against a moving target.

Certainly true, but given that light is (near as makes no difference) instantaneous in this case, having the target in your sights and hitting it are the same thing. If the range is increased enough, I suspect that this would be a much easier weapon to use than, say, projectiles, as there's no possibility of evasion.

Comment: Re:the layout sucks, thanks Dice ! (Score 1) 391

Of course, some people/corporations will make arguments relating internet to delivery services -- paying more for overnight shipping means you get the package/letter faster. Of course, this is a flawed argument for myriad reasons, not the least of which is that if someone mails me an overnight letter I don't then have to pay extra to receive it...

Comment: Re:Numerology (Score 4, Insightful) 183

Good point. I think, though, that they approached it completely backwards: they have presented a method for determining the information-theory voxel size of the universe (or whatever you like to call it), NOT the energy density, as TFS claims. That is, I think they should have started with the correct answer (10^-27 g/cm^3) and derived the voxel size from there. Then we could debate on the physical meaning of this voxel, which is a legitimate thing to talk about.

Comment: Re:Numerology (Score 2) 183

No, I think this information theory "approach" uses 10km^3 voxels:

Specifying the location of the 10^25 stars in the visible universe to an accuracy of 10 cubic kilometers...gives an energy density of about 10^-30 g/cm^3. ...But if the location has to be specified to the Planck length, then the energy density is about 117 orders of magnitude larger.

So they roughly recover the quantum mechanical (apparently incorrect) result if they use Planck length^3 voxels.

Not that I read the article of course, but this seems an odd thing to do, as you should probably be confining them to hbar units of phase-space, not just confining them to voxels.

Factorials were someone's attempt to make math LOOK exciting.

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