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Comment: Not that simple (Score 1) 222

by fyngyrz (#49201149) Attached to: Laser Takes Out Truck Engine From a Mile Away

You are making a LOT of assumptions. All of these matter: Ability of the mirror to dissipate energy prior to ablation or meaningful distortion. Collimation of the beam. Reflectivity of the mirror at the laser frequency. Ability of the laser to stay on target, and for how long. Distance from the laser. Atmospheric clarity and particulate density. Atmospheric turbulence. Disruption from atmospheric heating.

It's just not as simple as you paint it.

Comment: Re:how much it took (Score 1) 222

by fyngyrz (#49201115) Attached to: Laser Takes Out Truck Engine From a Mile Away

CIWS targeting is, as the acronym hints, "close in." You should think of the distance between the shooter (of anything) and the target as a lever. A tiny pivot at one end of the lever (the weapon's aim) translates to a "much" larger motion at the end of the lever (the point of impact.) Tolerances that will work at 100 yards aren't anywhere near close enough to work at many miles, or hundreds of miles in the case of missiles not aimed particularly at you (so you can be sure they will get close enough to hit.)

Comment: Suitable defensive grid? (Score 1) 222

by fyngyrz (#49201075) Attached to: Laser Takes Out Truck Engine From a Mile Away

There are other issues. That truck was relatively close, between 1 and 2 miles ("more than a mile away"). To hit an ICBM at apogee, even it it goes right over you, you are going to have to spend a lot of energy on atmospheric heating, and you'll lose even more to atmospheric distortion. We're talking 300 to 700 times the distance, depending on exactly what "more than a mile away" actually means. But it is certain that 30 kw at the source will not equate to 30 kw at the target at those distances. So now the problem becomes more than "hit the target", it is also "stay on target for X time", and that assumes that enough energy can be delivered to overcome the missile skin's ability to dissipate it. Because if you can't do all those things, you can't hurt the missile.

Also, the odds of it going right over you kind of suck.

Comment: Re: how much it took (Score 2) 222

by fyngyrz (#49201029) Attached to: Laser Takes Out Truck Engine From a Mile Away

I"m pretty sure a regular mirror would not be employed.

But here's some hand-wavy math.

If a mirror reflects 99% of the light that hits it at the laser frequency (remember, there's only one frequency to be covered), and the light that hits it can heat proportional to 30 kw (however one figures that), then the mirror is absorbing a 300 watt equivalent and reflecting the rest unless the reflective surface fails.

If the reflective surface is highly heat conductive and the beam isn't all that tightly collimated, likely it won't flinch at all. Like any impact, the effect is all about how much energy you can shoehorn into the smallest possible area. If the beam is ~1/3 of an inch on target, then given 99% reflectivity, it's effectively 1 kw / square inch. If the beam is 1/30th of a square inch on target, it's 30 kw/square inch absorption after reflection. So it makes quite a difference. I think.

Anyone who works with lasers and mirrors, feel free to step in and correct or expand.

Comment: ...with remaining eye (Score 1) 222

by fyngyrz (#49200937) Attached to: Laser Takes Out Truck Engine From a Mile Away

1) is if the laser is in visible light or not. If you can't see the red dot source a mile off, you can't evade it.

Pretty sure if you "see the red dot a mile off", the location where your eye was is just the steaming, goo-surrounded beginning of a well-cauterized hole that completely transits your head. Assuming tight collimation. With a broader 30 kw beam, your head would explode (steam pressure), and with a really broad beam, you'd turn into a human crisp before you had time to think "Hey! Las..."

Comment: STILL smells like a duck... (Score 1) 157

by fyngyrz (#49186083) Attached to: Astronomers Find an Old-Looking Galaxy In the Early Universe

Except that science collectively doesn't claim to know what happened at the points when the universe was dense enough and at high enough energy scales that it is speculated current laws of physics break down

Yes, that's my point exactly. They don't. Because they can't. Because the theory is based on assuming something happened that our physics can't describe. BB theory is therefore incomplete in a way that makes it unable to stand in the face of what at this time appear to be some very simple and reasonable questions. Questions physics force us to ask.

To stick with your analogy, the Big Bang theory isn't saying the baseball materialized spontaneously from the ground, but that it appeared at some point on that path, with some evidence that the trajectory goes back some where near the ground for loose definition of "near." In which case, there being a pitcher and it being spontaneously generated on that path both being consistent with current theories and observations

No. Quite wrong. The specific reason I use this analogy is that BB theory goes right to the ground -- fractions of fractions of fractions of a micrometer above -- such that the option of there being a pitcher or a ball launcher, or a firecracker under the ball, or a really strong dwarf cricket or even microbe, etc., has completely gone away. You cannot explain BB any further using our physics because they state that the theory covers it right back until it cannot. Consequently it either has to be some other physics, or else it's massively wrong. Theories that are rigorous but then, still within the context of their own propositions, devolve into "and then we don't know" or "because we have no idea"

BB theory may, as I said above, be quite correct, and we may need new physics to understand it. if that's the case, on that day, it becomes a complete and compelling theory to me. Until then, it's not.

As of right now, spotting a galaxy that shows what we understand to be evidence of being older than would be possible if BB theory is correct does not particularly surprise me, any more than finding evidence that "Thor" was just some dude with a really big hammer would surprise me in the context of the ideas that present the Æsir and Vanir as "gods." Because just as, at present, there are no physics that would actually make the idea of a god or gods credible in the face of objective, reality-based inquiry, there are no physics that actually make the idea of the BB credible in the face of same.

Comment: Re:If it smells like a duck... (Score 1) 157

by fyngyrz (#49185093) Attached to: Astronomers Find an Old-Looking Galaxy In the Early Universe

"Monoblock" or "the primordial monoblock" is a term for the presumed state of the presumed material comprising the presumed universe just before it presumably exploded. Everything, no exceptions, including space itself, all in one tiny... something, (tiny with respect to... something), that did.... something, and then [waves hands] Big Bang! Try this google search.

Science can trace the expansion of the universe backwards quite a ways, within the bounds of our understanding of physics as it stands and it makes sense, albeit some very strange and difficult to swallow sense. But go back far enough, and a point is reached where our physics simply do not serve to describe the previous state. At all.

I liken it to tracing a pitched ball backwards, not having been around to witness the pitch, but analyzing the arc of its trajectory and theorizing that the ball erupted spontaneously from the ground in order to arrive where it is. We can't account for such a spontaneous emission, but after all, hey, there's the ball, right? The immediate and obvious objection is that "but physics tells us that can't happen"... well, physics tells us the exact same thing about the big bang. That's why I consider the comparison apt.

I'm not saying the big bang theory is wrong; I'm just saying it is definitely unproven, and that there are severe and fundamental problems with attempts to prove it at this time. Tomorrow, we have new physics, and that may resolve everything very nicely. But until or unless that happens -- until someone shows how the "ball could erupt from the dirt, spontaneously or otherwise" -- personally, I'm reserving BB theory acceptance.

Comment: Re:1.2 what? (Score 1) 199

Budget cutbacks.

In careful consideration of this, and in light of the seriousness of the problem, I have determined that the appropriate reaction is to seize Canada. I'm pretty sure that congress will determine the commerce clause covers it, anyway. I'm writing my crook^w legislator this evening.

Comment: Re:Nope (Score 1) 231

by fyngyrz (#49165523) Attached to: Samsung Officially Unpacks Galaxy S6 and Galaxy S6 Edge At MWC

Having used both removable batteries and external battery bricks, the external battery brick is FAR more useful.

Probably so. Luckily, there's a much better way to go. Throw out the original battery, replace it with one that has several times the capacity, replace the back with the supplied replacement, and buy the appropriate hardshell if that's how you roll.

Result? More battery life than a brick, no having to plug in all the time, and no need to remove the battery until it dies, which will likely be some years down the road.

When I bought my Note 3 (SM-N900V), it wouldn't last a day. I'd have to turn it off (not use apps, etc.) before bedtime if I wanted it to have enough juice left to receive a call, text, IM or email, etc. -- it would hit 5% by 9pm or so. Once I replaced the battery, I just pop the thing on the charger about every other day while I'm sleeping and have no worries. It'll go three full days of use, but that does put the battery down to about 20%, so I tend to avoid it.

This makes the phone thicker and heavier. I don't mind a bit. But some people would.

It is much easier to suggest solutions when you know nothing about the problem.