6 ms·

A reason why I allow myself some skepticism on the feasibility of quantum computing is that if it were possible, I would have expected evolution to have used it

by Iv 7y ago

A reason why I allow myself some skepticism on the feasibility of quantum computing is that if it were possible, I would have expected evolution to have used it somehow. If it turns out that protein folding really use a quantum computation, I'll move quantum computers from the "too good to be true" category to the "probably revolutionary stuff that I will see in my lifetime" alongside with nuclear fusion and strong AI.

teraflop 7y ago
> if it were possible, I would have expected evolution to have used it somehow. That seems reasonable as long as you're consistent in applying the same skepticism to other inventions, such as the internal combustion engine and the wheel.
- Iv 7y ago
  The physical principles behind combustion engines and the wheel are displayed in many life forms. Their engineering constraints and goals differ. It is, however, reasonable to expect evolution to find a way to exploit quantum algorithms as it is very useful to several fitness advantages and is something that you would expect to be achievable through protein manipulations.
- aaron_m04 7y ago
  Bacterial flagella are rotary, so very close to being wheels.
- SolarNet 7y ago
  Fossil fuels are primarily biological in origin. Certainly we extract the energy in a much different way, but that energy capacity is there biologically (slow burn, turns out high speeds aren't actually that useful in nature). As for wheels, hip joints are a more efficient design of a rotatory system (multiple degrees of freedom). Wheels are much too simple a design to see much use in nature.
quotemstr 7y ago
Your argument doesn't stand up to cursory examination. There are all sorts of tricks of physics that evolution never found out how to use. Natural systems don't use the (macroscopic) wheel either, but that works great. Refrigeration works great, but nature doesn't use that either. Complex life has barely been around 540 million years ago. Why would you suppose evolution would have had time to explore the entire space of techniques that physics allows?
- Iv 7y ago
  Actually, rolling things, from seeds to eggs, including whole shrimps is a locomotion technique used by nature since a long time. The axle is something it does not use, and I would argue does not need. In all natural terrains, legs are a superior option. The physical principles behind refrigeration are witnessed in several places in nature.
  - xenadu02 7y ago
    Use of the vast majority of the radio spectrum is not used by any form of life that we know of. Being able to communicate non-visibly without giving away our position audibly would be a huge advantage (until your predators/competitors figured it out). Life isn't generally suitable to the use of really high energies like X-rays because it damages cells. It isn't suitable for low energies because it is difficult to create an individual receiving/broadcasting element at such a small scale. There absolutely are physical phenomena that life does not take advantage of.
    - changoplatanero 7y ago
      lasers would be another one, right? Is there any lifeform that can make a laser?
      - Iv 7y ago
        Is there any lifeform that needs it? With light sensors that basically give us line-of-sight range, I don't see which problem organic lasers would solve.
e2le 7y ago
How do you know it doesn't use it?
knzhou 7y ago
This argument proves too much. By that same argument, nuclear fission, ordinary CPUs, steam engines, rockets, helicopters, jets, X-rays, radio waves, superconductivity, superfluidity, air conditioning, liquid helium, liquid nitrogen, the Haber process, the fractional quantum Hall effect, Doppler cooling, graphene, long-distance satellite communication, gravitational waves, and GPS corrections for relativity all don't exist, because nothing in life is designed like them or takes advantage of them. You've literally taken us back to the 1700s. I know that it's fashionable to simply declare quantum computing is impossible, and there are some strong arguments in this direction, but this particular argument isn't one. The general reason people believe quantum computing is possible is that it describes just about all the things I mentioned above absolutely perfectly, along with literally thousands of other phenomena, with no deviations ever measured. This gives us good reason to assume quantum mechanics actually works, and if it does, then it's possible for quantum computing to work. (Also, of course you need to account for quantum mechanics to account for protein folding. You literally can't have chemical bonds at all without quantum mechanics.)
- Iv 7y ago
  The argument I propose is not a strong one. It is still an argument: if something is possible, why did evolution not use it? There are several possible answers: 1. Life may not have a use for it 2. It may be impossible to achieve with proteins and cells 3. It may not actually be possible For quantum computer I (weakly) believe that 1 and 2 are wrong: evolution and cognition would hugely benefit from quantum acceleration and biology operates at a scale where quantum effects are visible. I thought 3. slightly more likely but I'll readily admit that I am nowhere near the knowledge to be categorical about 2. And note that of the list of things you are giving, there are many that uses the same physical principles that are used by life: steam engine (expansion of heated gases), rockets (ignition of gas), jets (propulsion), helicopters (a rotating wing is a wing), radio waves/X-rays (the RF spectrum, which visible light is part of), etc... The rest, IMO, falls either under 1. or 2. For instance I doubt long-distance communication really offers a substantive advantage when you know whales can already contact each other at 100s of kilometers through shouts, and superfluidity may require conditions and materials that are impossible to reach for organic material. Note however that this last one is actually a kinda good (if weak) argument: if superfluidity was achievable through organic material and conditions close to the temperature and pressure average on earth, life would probably have found it, as it is clearly a useful property. If tomorrow we find that you can get room-temperature superfluids that are made out of C,H and O atoms, wondering why it is not found in nature will be a very good question.
jyounker 7y ago
Not quantum search, but sizable fraction of a second quantum coherence at room temperature: https://arxiv.org/pdf/0906.3725.pdf https://arxiv.org/pdf/0906.3725.pdf I suspect we’re just really bad at identifying quantum processes in living things.
api 7y ago
A bit of a further tangent but: I continue to believe that it's very likely that brains somehow leverage quantum computing. The human brain is able to accomplish computational tasks on only around 40 watts of power that destroy what we can accomplish using pretty much any known machine learning algorithm using tens or even hundreds of thousands of watts of power. Maybe our algorithms are primitive or wrong, or maybe the brain just is not a classical computer. The power of brains is so "unreasonable" that I've long suspected that there are only three possibilities: (1) Brains are quantum computers. (2) P=NP, or for a weaker form perhaps there exist large numbers of undiscovered algorithms that offer massive speed improvements over any currently known algorithm. (3) Brains or intelligence are "supernatural" or at least tap into something about nature that we fundamentally do not understand. I think option #1 is by far the most likely, especially given that brains excel most of all at search and quantum computing seems to really be able to speed up search. There is just no way classical computation can do what the human brain does on 40 watts. To me that strains credulity much more than any of the three options above. It just cannot possibly be so.
- lonelappde 7y ago
  Illogical. 40watt computers can also do things that destroy what human brains can do. I can load up a raspberry pi with logic to control robots and apply computer vision models and do some pattern learning. And the power of software is still rapidly improving. And computers can run on much lower power too, and likely even lower in future. There is no particular reason to believe that quantum is what makes brains work, as known quantum computers are super energy inefficient, and quantum effects are not observed in high temperature matter (not counting quantum effects of photons) like humans. How could you think our algorithms are not primitive and wrong? They've been improving at exponential rate since almost forever, with no hints that they've reached optimality beyond tiny pockets.
  - api 7y ago
    I think you're ludicrously underestimating what brains and biological neural systems in general can do.
zamalek 7y ago
You'd be absolutely correct if we knew how everything in nature works. We haven't explained everything that evolution has done and QC has been proposed for some of those things, for example the quantum mind hypothesis (where there are good arguments both for and against it). In a way, your argument makes the same mistakes that it claims these scientists are making. > strong AI I'm not sure what you're arguing here; evolution has achieved this in the form of the human mind. I strongly doubt we are as close as some believe to creating SAI, certainly not in the lifetime of any living human being, but arguments that hinge on natural demonstrations require that this is eventually possible.

by Iv 7y ago

teraflop 7y ago

> if it were possible, I would have expected evolution to have used it somehow. That seems reasonable as long as you're consistent in applying the same skepticism to other inventions, such as the internal combustion engine and the wheel.

Iv 7y ago
The physical principles behind combustion engines and the wheel are displayed in many life forms. Their engineering constraints and goals differ. It is, however, reasonable to expect evolution to find a way to exploit quantum algorithms as it is very useful to several fitness advantages and is something that you would expect to be achievable through protein manipulations.
aaron_m04 7y ago
Bacterial flagella are rotary, so very close to being wheels.
SolarNet 7y ago
Fossil fuels are primarily biological in origin. Certainly we extract the energy in a much different way, but that energy capacity is there biologically (slow burn, turns out high speeds aren't actually that useful in nature). As for wheels, hip joints are a more efficient design of a rotatory system (multiple degrees of freedom). Wheels are much too simple a design to see much use in nature.

quotemstr 7y ago

Your argument doesn't stand up to cursory examination. There are all sorts of tricks of physics that evolution never found out how to use. Natural systems don't use the (macroscopic) wheel either, but that works great. Refrigeration works great, but nature doesn't use that either. Complex life has barely been around 540 million years ago. Why would you suppose evolution would have had time to explore the entire space of techniques that physics allows?

Iv 7y ago
Actually, rolling things, from seeds to eggs, including whole shrimps is a locomotion technique used by nature since a long time. The axle is something it does not use, and I would argue does not need. In all natural terrains, legs are a superior option. The physical principles behind refrigeration are witnessed in several places in nature.
- xenadu02 7y ago
  Use of the vast majority of the radio spectrum is not used by any form of life that we know of. Being able to communicate non-visibly without giving away our position audibly would be a huge advantage (until your predators/competitors figured it out). Life isn't generally suitable to the use of really high energies like X-rays because it damages cells. It isn't suitable for low energies because it is difficult to create an individual receiving/broadcasting element at such a small scale. There absolutely are physical phenomena that life does not take advantage of.
  - changoplatanero 7y ago
    lasers would be another one, right? Is there any lifeform that can make a laser?
    - Iv 7y ago
      Is there any lifeform that needs it? With light sensors that basically give us line-of-sight range, I don't see which problem organic lasers would solve.

e2le 7y ago

How do you know it doesn't use it?

knzhou 7y ago

This argument proves too much. By that same argument, nuclear fission, ordinary CPUs, steam engines, rockets, helicopters, jets, X-rays, radio waves, superconductivity, superfluidity, air conditioning, liquid helium, liquid nitrogen, the Haber process, the fractional quantum Hall effect, Doppler cooling, graphene, long-distance satellite communication, gravitational waves, and GPS corrections for relativity all don't exist, because nothing in life is designed like them or takes advantage of them. You've literally taken us back to the 1700s. I know that it's fashionable to simply declare quantum computing is impossible, and there are some strong arguments in this direction, but this particular argument isn't one. The general reason people believe quantum computing is possible is that it describes just about all the things I mentioned above absolutely perfectly, along with literally thousands of other phenomena, with no deviations ever measured. This gives us good reason to assume quantum mechanics actually works, and if it does, then it's possible for quantum computing to work. (Also, of course you need to account for quantum mechanics to account for protein folding. You literally can't have chemical bonds at all without quantum mechanics.)

Iv 7y ago
The argument I propose is not a strong one. It is still an argument: if something is possible, why did evolution not use it? There are several possible answers: 1. Life may not have a use for it 2. It may be impossible to achieve with proteins and cells 3. It may not actually be possible For quantum computer I (weakly) believe that 1 and 2 are wrong: evolution and cognition would hugely benefit from quantum acceleration and biology operates at a scale where quantum effects are visible. I thought 3. slightly more likely but I'll readily admit that I am nowhere near the knowledge to be categorical about 2. And note that of the list of things you are giving, there are many that uses the same physical principles that are used by life: steam engine (expansion of heated gases), rockets (ignition of gas), jets (propulsion), helicopters (a rotating wing is a wing), radio waves/X-rays (the RF spectrum, which visible light is part of), etc... The rest, IMO, falls either under 1. or 2. For instance I doubt long-distance communication really offers a substantive advantage when you know whales can already contact each other at 100s of kilometers through shouts, and superfluidity may require conditions and materials that are impossible to reach for organic material. Note however that this last one is actually a kinda good (if weak) argument: if superfluidity was achievable through organic material and conditions close to the temperature and pressure average on earth, life would probably have found it, as it is clearly a useful property. If tomorrow we find that you can get room-temperature superfluids that are made out of C,H and O atoms, wondering why it is not found in nature will be a very good question.

jyounker 7y ago

Not quantum search, but sizable fraction of a second quantum coherence at room temperature: https://arxiv.org/pdf/0906.3725.pdf https://arxiv.org/pdf/0906.3725.pdf I suspect we’re just really bad at identifying quantum processes in living things.

api 7y ago

A bit of a further tangent but: I continue to believe that it's very likely that brains somehow leverage quantum computing. The human brain is able to accomplish computational tasks on only around 40 watts of power that destroy what we can accomplish using pretty much any known machine learning algorithm using tens or even hundreds of thousands of watts of power. Maybe our algorithms are primitive or wrong, or maybe the brain just is not a classical computer. The power of brains is so "unreasonable" that I've long suspected that there are only three possibilities: (1) Brains are quantum computers. (2) P=NP, or for a weaker form perhaps there exist large numbers of undiscovered algorithms that offer massive speed improvements over any currently known algorithm. (3) Brains or intelligence are "supernatural" or at least tap into something about nature that we fundamentally do not understand. I think option #1 is by far the most likely, especially given that brains excel most of all at search and quantum computing seems to really be able to speed up search. There is just no way classical computation can do what the human brain does on 40 watts. To me that strains credulity much more than any of the three options above. It just cannot possibly be so.

lonelappde 7y ago
Illogical. 40watt computers can also do things that destroy what human brains can do. I can load up a raspberry pi with logic to control robots and apply computer vision models and do some pattern learning. And the power of software is still rapidly improving. And computers can run on much lower power too, and likely even lower in future. There is no particular reason to believe that quantum is what makes brains work, as known quantum computers are super energy inefficient, and quantum effects are not observed in high temperature matter (not counting quantum effects of photons) like humans. How could you think our algorithms are not primitive and wrong? They've been improving at exponential rate since almost forever, with no hints that they've reached optimality beyond tiny pockets.
- api 7y ago
  I think you're ludicrously underestimating what brains and biological neural systems in general can do.

zamalek 7y ago

You'd be absolutely correct if we knew how everything in nature works. We haven't explained everything that evolution has done and QC has been proposed for some of those things, for example the quantum mind hypothesis (where there are good arguments both for and against it). In a way, your argument makes the same mistakes that it claims these scientists are making. > strong AI I'm not sure what you're arguing here; evolution has achieved this in the form of the human mind. I strongly doubt we are as close as some believe to creating SAI, certainly not in the lifetime of any living human being, but arguments that hinge on natural demonstrations require that this is eventually possible.