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Comment Re:Concentrations (Score -1) 216

Um, just a minute - let's insert some math here:

0.18 trillion = 180 billion equivalent units
400 million *7000 = 2800 billion equivalent units

So, if the article summary is correct over 90% of any anthro warming is not due to CO2, proving the skeptics correct.

I strongly doubt that the article is correct.

Comment Re:Well it is far, far away (Score 1) 110

Or, possibly this is an alien factory planet...

To make more energy available, they take all of a solar system's rocky mass and put it into an orbit skimming close to the central star. That way the metals can be easily separated out, and worked. Since heat engines become more efficient at higher temperatures (especially when you have to radiate waste heat to space), much more energy is available for engineering processes.

This planet isn't "a complete mystery" - it is final, clinching proof of extraterrestrial intelligent life!

Or not...

Comment Re:Wait, what? (Score 1) 134

and the vast majority are complete and utter failures.

I would add to this, though - they may have failed, but they likely learned something that will permanently increase their value to society. And, because of that, permanently increase their income.

I strongly recommend that all college students try to start a business. Yes, you will likely fail - but you will be exposed to thing that will change your perspective forever.

Comment Re:US Metric System (Score 1) 1387

100 C has no practical application for most values of real life.

You don't boil water by setting something to 100 C (or 212F for that matter). You turn up the dial to medium-high and wait for bubbles. Or stick it in the microwave for some number of minutes.

0 C also not so practical. My refrigerator's freezer compartment lets me choose on a scale not related to C or F. In any case, it's a temperature below freezing.

Not to say metric is without merit, but it's practical applications are not a good argument for people familiar with imperial units.

Comment Re:Retire at 20 (Score 4, Insightful) 358

Actually, I pretty much disagree entirely with that analysis...

The question is not "sell low" or "sell high" - you do not know the future, so that fact that it went up is not available to you before the decision. The question is are you getting enough that your risk is significantly decreased.

For example, if your company is generating free cash flows of $2M, you will usually get a valuation of $10M. That is the market rate for a startup that's breaking out. (It can change based on other factors, of course, but that is the starting point.) As a public company, that $2M is worth about $30M. You might look at that difference and claim "unfairness", but it is the price difference between concentrated risk and unconcentrated risk. To put it simply, if that wasn't the price difference in risk then most deals would not be made - either the startup would refuse to sell or the large company would refuse to buy.

Honestly, if this is your first company you are going to think that any price isn't fair. And when you don't accept the price, you'll be horrified when the company loses its value a little later. And then next time, you'll understand the price difference and you'll sell.

But the important thing is to keep building companies - I've started quite a few, and there is no job like it!

Comment Re:Retire at 20 (Score 5, Insightful) 358

If he started a company in his teens, I doubt he wants to relax the rest of his life...

He should sell. The reason small companies sell to large companies is to decrease concentration of risk for their owners. He, as an owner of a small company, needs to deconcentrate his risk. He will have another company he wants to work on - he probably already has some ideas. It is far easier to do that after selling your first company, and far harder to do that after missing the only opportunity to sell.

The simple fact is a cash out event gives you great options for your future work. If you don't sell, there is a high risk that the company will fail before you can personally cash out - this is true of all start-ups.

Comment Re:Complain to the Bar (Score 4, Insightful) 153

Sometimes that is a coin toss when comparing highly educated with highly experienced or two similar candidates.

In cases like this, or where there is plainly not enough information, leave that one blank -- don't vote for either unknown. Unless your ballot stupidly requires you not to leave any races blank (are there such ballots?)

Comment Re:Buddhism - the less abhorrent religion. (Score 1) 348

I find pretty much all religion abhorrent. Buddhism however, while still abhorrent for believing in mystical ideas that go against the simplest (and therefore best) definitions of reality, is definitely less abhorrent than the others. I've seen a lot of quotes from the Dalai Lama that I really appreciate and can agree wholeheartedly with.

Seems to me that someone who abhors religion and mysticism would agree wholebrainedly rather than wholeheartedly.

Comment Re:Solar powered jet engine (Score 1) 590

That's no problem at all using unobtainium, of course!

Actually, my math is off by a factor of 10 - I didn't convert kg to N correctly. The corrected result is:

FlyingMass = OtherStuff + 0.525 * FlyingMass

So your aircraft has to be half solar cells, roughly speaking. And, yes, the solar cell area is a bit on the large size...

Comment Re:Solar powered jet engine (Score 4, Informative) 590

To inject some math into the discussion:

ThrustToKeepFlying = FlyingMass / LiftToDragRatio
PowerToKeepFlying = ThrustToKeepFlying * Velocity = Velocity * FlyingMass / LiftToDragRatio

Typically LiftToDragRatio is about 20 or so. Airplanes don't really make sense unless they are faster than other vehicles, so Velocity needs to be 100-300 m/s. (Typically, jets fly just under Mach 1, where they have the least drag/greatest power)

FlyingMass = AircraftMass + PayloadMass + EngineMass + PowersourceMass

Since we are using unobtainium to build our aircraft, it doesn't weigh anything. And we'll just say that we can fly arbitrarily large airplanes for a single passenger, so PayloadMass is essentially zero as well.

The best solar cells are about 300W/kg (http://en.wikipedia.org/wiki/Solar_panels_on_spacecraft), and the best electric engines are about 6 kW/kg. So

FlyingMass = OtherStuff + PowerToKeepFlying / 300 + PowerToKeepFlying / 6000 = OtherStuff + 0.0035 * PowerToKeepFlying

FlyingMass = OtherStuff + 0.0035 * ( 300 * FlyingMass / 20 )

FlyingMass = OtherStuff + 0.0525 * FlyingMass

OtherStuff = 0.9475 * FlyingMass

So this says that as long as your airplane and payload are under about 95% of the engine / power source mass, it is at least possible. Structures that light are not really an issue - the real issue is only flying during the day and in good weather. (And, of course, it would cost an arm and a leg!)

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