Comment by gnramires | Hacker News Reader

Comment by gnramires | Hacker News Reader

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Calling those robots is a bit misleading, because they lack self-control. Control logic we know is large for very small robots. If you want a micron-scale robot you only get about 100 transistors for its "intelligence"[1]. There are certainly things it could do, but probably not autonomously navigate, map and recognize tumors.

We just don't have the expertise for those kinds of thing, at least not yet. A plethora of sensors (that can detect cancerous cells) and this sort of technology would be needed. We'd essentially be trying to create artificial cells, a monumental task nature took billions of years in refinement (even if we can find shortcuts sometimes) -- too many very complex systems (energy, better sensors, better movement inside the body, "cognition", etc.).

Maybe in 50 years of continued research? 100 years? I don't know.

[1] The state of the art is about 100 transistors per square micron. This assumes you could drive and interface with them adequately. Cells accomplish all they do without any transistors at all, it's all protein-based sensors and DNA-encoded behavior, I believe.

I think the question that OP (and myself) is asking is "given Magic Robots (tm), could we essentially cure cancer?"

Obviously, as you note, there are enormous (or rather, extremely tiny, but very hard!) problems with this. However, it's not all doom and gloom.

I could imagine that going in the 3D dimension for example, could enable another 100X increase in transistor count. In addition, you shouldn't need to actually do the computation onboard for cancer applications, just transmit it via some method, say RF to an outside computer that can do the compute work. Finally, cells are something like 10-30 um in diameter, which gives a lot more room to play with than 1um (the linked paper has scale of about 100um I believe).

Anytime I see a title starting with "scientists" did X... the history is BS

"Smart weapons" kill innocent people all the time, no matter how many times we repeat smart in their model name. GPS still lead truck drivers directly to the bottom of a lagoon.

If we can't teach a huge machine full of circuits to distinguish between an ambulance or a tank, how we can realistic trust that tiny machines, with no space at all for complex circuits, will be able to diferenciate between a tumor or our hypothalamus?

What would happen if the patient approach a magnet accidentally? Will the army of nowaybots be displaced enough cm to try to fry your pancreas assuming that they are in a different location?

100 transistors might be enough for a “triangulation” circuit. Hold three RF emitters around the tumor outside the patient’s body and the robot will navigate to the point equidistant from all three emitters and start destroying tissue. You could move the orbs around to eat away the tumor, then filter them out of the bloodstream with a dialysis machine.

Probably not with dialysis given dialysis works on semi permeable membranes. More likely a magnet.

Maybe the route toward what I'm envisioning (and hoping for) is genetically engineered or enhanced cells. Modify and existing system that already does a lot instead of trying to recreate a cell from the ground up.

We've been making artificial cells for quite some time, but they're purpose is more of a model than anything else. A way for us to study what happens when you take away everything and just start from the very basics.

What you're talking about sounds more like artificial tissues and organs, which is an active area of study, although I don't immediately see how we might "engineer-out" cancer. There exists a world in which we develop tissues that age slower, but the more likely (not that it's happening anytime soon) scenario is very cheap organs that we can swap out for ours.

I sense robots not made out of similar materials may be easier for dealing with a cancer. It’s “out of band” - cell’s for instance seem to communicate through chemicals so the robot cells are likely to respond (or not) to the things in the biological system.

As for more traditional robots with ~100 transistors, why do they need to be autonomous? Why not mesh network them and control them as drones?

This isn't far from what immunotherapy is doing. Cancer can only thrive when it avoids an immune response, either by looking sufficiently like a healthy cell to remain below the radar or actively suppressing actions of the immune system.

Immunotherapy looks for ways to counteract this 'feature' and allow the immune system to do its job and murder the bastards.

We're still effectively in the early days of this approach to treating cancer and results are mixed, but it shows incredible promise and I feel that it ultimately will be the way we beat most if not all cancers.

If you think of transistors as analog computational devices, 100 is not that small. There are animals with ~200-300 neurons, so it's at least within the range of possibility to have a fairly autonomous robot with only 100.

A neuron contains thousands if not millions of transistor-equivalents in the form of gene level and ion level switches. I'm not saying that you couldn't do it with 100 transistors, or that everything in a neuron is needed for this application, but I just wanted to clarify.

Right, the transistor is not fully simulating a neuron, just a first order approximation of the electrical impulse response. It's close enough for government work, as they say.

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