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34

This question is sort of difficult to answer in an objective way, because it depends very strongly on your definition of "best." Natural selection favors traits which provide a reproductive advantage; no more, no less. Could our eyes be better by the standards of modern optical design, in terms of precision and features? Sure. I could easily design a camera ...


23

How about diagnostic methods in modern medicine? Nuclear magnetic resonance (NMR) - it wouldn't even make sense to talk about it without quantum mechanics, because it depends on the quantum mechanical concept of spin Positron emission tomography - hey, the name says it all, not only do you apply quantum mechanics, but you have a direct application of ...


20

The first common application that comes to my mind would definitely be the LED. From there on, everything that has even remotely to do with a semi-conductor. Furthermore, these days all chemical reactivity is understood in terms of quantum mechanics.


13

Quantum theory is so integrated into every day life that I think most people would find it very difficult to imagine a world in which we'd never developed quantum mechanics. First, without quantum physics, we would probably not understand the behavior of materials well enough to have invented modern semi-conductors. No modern electronics. No computers. ...


13

QM already made a big change to our lives: Without QM no transistors. Without transistors, no modern computers. Without modern computers, you wouldn't have been able to ask your question here. Before an integrated circuit (that encapsulates an array of transistors in a piece of computer equipment, say) is mass produced, one must do a huge number of ...


13

This is a common misconception -- evolution has not stopped a million years ago leaving all the creatures in the "best possible state"; it is a continuous pursuit of adapting to the current environmental conditions, with only aim in reproductive success. Moreover most of the population stays in even more suboptimal surroundings due to random mutations (the ...


13

[Updated to correct a couple of mistakes pointed out in comments. Thanks!] At my age, it's clear that there's room for at least one major improvement: more accommodation. Accommodation, in this context, means the ability of the eye to focus at different distances. This is accomplished by changing the shape, and hence the focal length, of the lens. The lens ...


11

The answer is an emphatic yes. Essentially this is what Charles Babbage did (look him up on Wikipedia). Also look up his Analytical Engine. This is accepted as the first computer that is Turing Complete. Therefore, by the Church-Turing thesis any computation done by any kind of physical computer can also be done on a mechanical computer. Parts of Babbage's ...


10

There are several different levels of advanced in quantum mechanics. I will try to answer using these levels of quantum mechanics: Basic: single particle or single particles interacting with a single atom/nucleus, or classical field picture--- anything Einstein would have been comfortable with. Advanced: highly entangled many-body quantum mechanics, ...


10

To list some more applications: UltraPrecise clocks. The most precise one, was built at NIST in 2010, based on a single aluminum atom (ion), in an ion trap. As is reported here The clock would neither gain nor lose one second in about 3.7 billion years. These clocks have many applications, from fundamental physics researches to GPS and navigation systems. ...


10

On the one hand, the caption under the image of the sphere being held by one of the member of The Avogadro Project reads as follows: The roundness delta of the finished sphere (being held above) is about 50 nm on a 93.6 mm diameter. It is believed to be the roundest object in the world. So that its departure from mathematically perfect sphericity ...


8

We know exactly where the spacecraft is, and it knows pretty well where we are. Distance does not aggravate the accuracy of aim problem, indeed the further apart the less relative motion, so aim gets easier. The problem is signal attenuation by dispersal. i.e. at twice the distance, the signal will be a quarter of the strength. The solution, for Voyager, ...


6

The moore's (empirical) "law" states that the number of transistors in a chip increases exponentially (doubles every 2 years). So the question is : is there a hard limit in the number of transistors in a chip? Or, in other words : Are there limits on the size of a chip and on the size of transistors? Indeed there are (almost). The matter is made of atoms, ...


5

Yes. A toy in the 1960s provided geeky kids with flip-flops and programmable logic implemented in plastic, rubber bands and short sections of plastic straws. It was called the Digi-Comp. It could be "programmed" to be a 3-bit shift register or counter. Though it was limited to three flip-flops and three logic sections, in principle it could have had ...


5

The human eye is an indifferent camera. Compared to a hawk's, it is laughable. A hawk can sit on top of the Empire State Building and make out a dime on the sidewalk. What makes the human eye any good at all is the software behind it: what our brains provide. You do realize that what really focuses on our retinas is an upside-down, tunnel-vision image that ...


5

This question can’t be answered exactly properly. The eyes we humans have evolved to be “about” the best available to us hominids. There are other species of life with eyes better adapted for their econiches. Eagles and hawks have eyes capable of far better resolution at great distances. They can soar 500 meters above the ground and spot a small animal ...


5

The quantum mechanical semiconductor-based transistor is the technological backbone behind all modern computers. So the internet runs off quantum mechanics. It is a correction in the sense that you don't need quantum mechanical principals to build computers, or even transistors, but semiconductor technology makes the computers small enough to be as ...


5

As always, a communication via electromagnetic radiation depends on both ends. Uplink from earth can be done with a lot of power and big dishes, of course. Downlink is limited to the power of the nuclear battery on board but has a rather impressive 2.7 meters dish!. On top of that they use a rather slow bitrate, I think with a lot of redundancy. All this ...


5

As an ex-physicist who now works as a quant in power markets I think it's safe to say the physics of the matter will be swamped by the economics in commodities and how power markets work. Two things to note: power prices are set by markets and not by the viability of the technology (prime mover) solar is hard to make money with w/o a long term Power ...


5

Mobile phones output UHF and long microwave frequency radiation; roughly 1GHz. These are not ionising radiations, which begin at ultraviolet light frequencies and above (several eV photon energies and above). 1eV is about 250THz, or five orders of magnitude greater than GHz photons in energy per photon. GHz photons thus have negligible effect on atoms and ...


4

In fact, we already have imaged extraterrestrial planets. You can find a list here, with perhaps the most famous system being HR 8799. Of course, that quote was referring to Earth-like planets, and you can see from the list I linked that everything we've seen is more massive and further out than even Jupiter. The challenge that confronts direct imaging is ...


4

I think quantum engineering of magnetism could be an appropriate answer to the question. Indeed the microscopic origin of magnetic field produced by iron for instance can be explained thanks to the old microscopic model by Ampere relying on a classical macroscopic electrodynamical analogy. But this model is not fully consistent with classical physics of ...


3

Martin Rees is being a bit optomistic, both the Terrestrial Planet Finder and Space Interferometry Missions were canceled because of lack of money.


3

a few different answers: no, it's easy to imagine small improvements: more regular lenses, wider spectrum sensibility, more than three color sensors... not only not the best possible, but also have some fortuitous bad choices, the most commented is the retina orientation that makes it easy to detach with a big impact. the very similar but independently ...


3

Have my degree in space engineering (that's space, not aerospace; no airplane stuff in my learning) so I figured I should give this answer a go. The NASA engineers plan this type of system thusly: After deciding on the high-level mission parameters, they make a list of several different landing systems. For MSL, this included the final design, aerobraking, ...


2

When silicene is buckled on the substrate it has a substantial band gap or in other words it can be turned on or off thus making it appropriate for digital applications. Graphene doesn't have a band gap so it isn't so good for digital circuits. Although techniques have been developed to produce a band gap and transistors have been made, they say that the ...


2

Note: in computing, mechanical device will generally mean any kind of physical device. No so for physicists. Then a problem is said to be mechanized as long as it can be handled by any kind of physical device (generally an electronic computer). You can rely on the turing completeness of computers to presume that anything you can compute can be computed by ...


2

the simple answer is no. Materials for an Earth elevator are at least one order of strength too weak at this time. Mars gravity is around 0.378 of earth, so materials are still too weak. The long answer is much more complicated: 1. Taper of the tether plays a role as much as the safety factor you want to engineer into your elevator, how much a tether can ...


2

At first glance, this is more an engineering question than a physics question, lurscher's comment actually answered it: Engineers think about possible solutions and their implications, test some of them in simulations and finally test some in real life or with models. Note that 'think about their implications' actually means doing tons of calculations, doing ...


2

This is only a response to your edit: EDIT: From what I experienced, experiments are already producing results, when theorists are still trying to fit their theories to the data. So why do you need the theoretical calculations then? Do they have predictive power that would be found easier and more precise with experiments? What sort of predictive power ...



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