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There are two approaches to this concept:

1) One heavily rooted in Physics, Math, and well understood Mechanical properties that says it is not feasible.

2) One heavily dogmatic approach that boils down to a fundamental misunderstanding of Engineering and it's limits.

There are things that can be done, and there are things that cannot be done.

Examples of things that can be done:

1) Human travel to Mars - It's hard but very feasible

2) Economically Positive Controlled Fusion - It's harder than getting a man to Mars, the economics of investing in the technology are difficult to justify relative to things like oil exploration, but it remains theoretically, if not technically, possible.

3) Completely Green Energy on Earth - Technical, political, and economic forces make this goal challenging but it is very possible if we try as a species.

Examples of things that cannot be done:

1) Faster than light travel - It's not physically possible with our current understanding of the universe, and nothing indicates this will be changing at any point. There are mathematical constructs that imply it's a possibility, but the physical requirements of these constructs are considered super unlikely to exist (and in some senses have very little meaning). Unless our understanding of the physical world changes to include materials like the ones described mathematically, this is thoroughly impossible.

2) Fly People 1000s of miles on 1 fluid ounce of gasoline - The energy isn't chemically in the substance. Unless you have some new fission and/or fusion mechanism (see earlier) this is physically impossible. Even if you could beat all of our observations around the engine cycles and overcome the theoretical maximum efficiencies (e.g. extract 100% of the energy from the gasoline), it would still not be possible because the raw energy required to perform the function of raising people into the air and changing their momentum is so much greater than what is chemically available in that much gasoline.

3) Pack enough energy safely into air via sound (or another mechanism) to allow for wireless charging - You should have seen this item coming. For reasons outlined by people who have spent much more time on this than I have, this is physically impossible. Long-range cohesive sound waves : not possible. Air efficiency for sound transmission : very very poor. Using EM runs the risk of all sorts of nasty side effects (it burns, it burns). Lasers are the only thing I can think of that could work, they're coherent and relatively efficient, they could target high density solar cells to charge the phone right? Yep, they sure could. Bill Gates investigated high energy lasers as a means of killing mosquitos in developing nations to prevent the spread of malaria, they built a fantastic system that worked perfectly, the concern over injury or loss of human life was just too great so they abandoned it. Would you want to get laser burns every so often in trade for wireless phone charging? I don't.




I've worked on a few laser based wireless power systems and I don't see it easily becoming safe enough for consumer use at power levels that are useful. For industrial/military use, the only thing keeping them from being off the shelf is their high cost and maintenance requirements (oddball cooling system requirements and very clean optics).

If you want to charge your phone on the order of 1w/hr, it's possible, any more power than that, consumers can't maintain equipment good enough for it to work. The main limiting factor for the power level is keeping things clean and scratch free enough. If you figure that out, it is worth more than wireless power system is (and I can I buy a few?).

One of the systems I worked on could deliver 1kW at 100m, and even something as small as a 0.5% reflection could set your clothes on fire if you were close to the reflection. 1KW is less power than what you can draw from most standard consumer wall outlets.


> w/hr

Did you mean W (watt) = J/s which is a unit of power?




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