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New Optical Switch Up to 1000x Faster Than Transistors

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61–70 of 94 posts

Re: New Optical Switch Up to 1000x Faster Than Transistors

#61
post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

So they were right about computers the size of entire buildings, they were just off by 100 years?

1 GHz allows for photon to move 3 m per cycle in vacuum. 10 GHz is 30 cm. Even less in fiber cable. I think that's a fundamental restriction of a size of an individual computing module. Of course you can stack modules in entire buildings just like you can stack cpus in servers in data center now.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#62
post #50
post #10

Earlier quoted context omitted.

Switching/routing usually requires significant information processing (e.g. decode packet header, match destination address against routing tables, etc.). This necessitates 10k or more gates. All-optical computing can't deliver this level of integration density, nor the performance at reasonable power levels. Maybe there will be some smart way to pre-encode routing information onto packets to reduce processing requir…

Being able to do any kind of computation in the optical domain would benefit telecommunications immensely. Basic things like optical muxing/demuxing and serialization/deserialization would be fantastic.

[deleted]

Re: New Optical Switch Up to 1000x Faster Than Transistors

#63
post #50
post #10

Earlier quoted context omitted.

Switching/routing usually requires significant information processing (e.g. decode packet header, match destination address against routing tables, etc.). This necessitates 10k or more gates. All-optical computing can't deliver this level of integration density, nor the performance at reasonable power levels. Maybe there will be some smart way to pre-encode routing information onto packets to reduce processing requir…

Being able to do any kind of computation in the optical domain would benefit telecommunications immensely. Basic things like optical muxing/demuxing and serialization/deserialization would be fantastic.

I was going to say "But wavelength/polarization multiplexing is the norm", but you have "fiber network design" in your about so I'm wondering what I'm missing - I guess you mean dynamic muxing, essentially routing? SerDes is of course annoying.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#64
post #43

Earlier quoted context omitted.

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule. The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be w…

Appeal to authority is only a fallacy when the authority is not an actual authority on the exact topic being mentioned.

Your broader point is right; obviously if we stop to poke at certain assumptions, the occasional one will collapse.

However, the pathway you’ve just suggested is less practical than you think. The GP is talking about a systematic, coordinated exploration effort of known unknowns.

Metaphorically - he/she is saying that there’s more likely to be gold at the unexplored end of gold mine, not in the excavated dirt.

It’s a fair assumption to keep in practise.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#65
post #43

Earlier quoted context omitted.

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule. The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be w…

Sure, but this argument could be used for any statement. It's not very compelling.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#66
post #43

Earlier quoted context omitted.

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule. The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be w…

It's not actually an appeal to authority as such - authority implies (usually) institutional accreditation, whereas here we are pointing out the situation is so complex opinions without years of study are more or less pointless.

Then, when we have two e.g. physicists, who both know quite well what they are discussing, and one of them is more famous and potentially through their prestige succeed in ridiculing their less recognized colleague, we are at the "appeal to auhority" position.

One famous example is that of Ernst Mach who was was positivist (i.e. did not respect theory whose constituents you could not directly measure) and ridiculed Boltzmanns kinetic theory of gases because Mach did not believe in atom theory (!). Boltzmann's theory was effectively attacked precisely from position of authority.

So, if a layman and a physicist argue what is possible, it is very likely while both of them may be wrong, the layman likely does not have any understanding what their position implies.

So in my opinion, you can have a pathological appeal to authority sort of situation only when two equally skilled persons have an argument an the institutional prestige of one of them is used as an appeal for them.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#67
post #5

In reality, all-optical computing is mostly a terrible idea: fundamentally, it cannot reach the integration density of electronics. It boils down to the elementary differences between Fermions (electrons, neutrons, etc.) and Bosons (photons, etc.). Their intrinsic behavior determines the interaction with matter, i.e. conductive/absorptive properties. As a result, optical wires (waveguides) have to be sized roughly at…

I don't know anything about the topic, but it does make me wonder. Our problem does not seem to be a lack of transistors to make all manner of specialized single purpose logic. We do see to be stuck when it comes to single core performance. I wonder if a new technology like optical could be used to add a single core accelerator to supplement existing chips.

Re: New Optical Switch Up to 1000x Faster Than Transistors

#69
> A new optical switch is, at 1 trillion operations per second, between 100 and 1,000 times faster than today's leading commercial electronic transistors

No, a CPU's clock speed is not the speed at which its transistors can transition. Clocks are multiple gates long (roughly, 10-20), and are not the only delays in a system. So a CPU running at a clock speed of 5 GHz could reasonably be switching each transistor at a rate approaching 100 GHz. (Most of the time each individual transistor is not switching, since only their last switch within a clock cycle is typically meaningful.)

Re: New Optical Switch Up to 1000x Faster Than Transistors

#70
post #43

Earlier quoted context omitted.

We're in an interesting point: there is so much we don't know but in order to learn more everything we do must fit in the already immense amount of knowledge that we accumulated so far. In the vast majority of cases this requires that the people who want to nudge the frontier a bit further must first dedicate a good portion of their life's studying what we know, and as the result sounding a bit arrogant when they exp…

That’s a pretty long way around to what is essentially an appeal to authority. You’re right about the knowledge and devotion required of frontier pushers. History is full of people who challenged this thinking and completely overhauled human understanding of a topic, though, often in the face of relentless ridicule. The error (in your telling) is equating knowledge with confidence. Knowledge is knowing you might be w…

> History is full of people who challenged this thinking and completely overhauled human understanding of a topic

At the risk of argumentum ad logicam, this is a textbook example of survivorship bias. History is also full of people who were adamant they were correct in the face of ridicule, and turned out to be wrong anyway.

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