benwr(Ben Weinstein-Raun)

Karma: 205

benwr 6 Mar 2020 21:16 UTC
5 points

in reply to: methree’s comment on: Coronavirus: Justified Practical Advice Thread
It is possible to both rinse your phone and put copper tape on it.

benwr 4 Mar 2020 0:21 UTC
1 point

in reply to: MalcolmOcean’s comment on: Coronavirus: Justified Practical Advice Thread
Yeah, you’re right that I imputed a particular mechanism that isn’t supported by the Wikipedia page—thanks for pointing that out. I do still think that the ions-getting-on-things mechanism is part of the story, mostly because the reduction sizes are really large. This could indicate either (a) that most microbes end up on surfaces first via touch surfaces, and spread from there, or (b) that copper ends up on nearby surfaces. Or some of both.

In this particular case, though, I think it’s quite likely (because I’ve seen my hands turn a bit blue) that in fact copper and copper oxides are getting on my hands as a result of the tape.

benwr 3 Mar 2020 22:01 UTC
1 point

in reply to: Ben Pace’s comment on: How to fly safely right now?
Oh, whoops, I somehow misread your original post (“shave” was edited to “have” in my brain)

benwr 3 Mar 2020 21:19 UTC
4 points

in reply to: Ben Pace’s comment on: How to fly safely right now?
Another random thought: wearing gloves is probably not a great idea in the default case, but if you wear gloves and then replace them, it seems like that’s probably about as good as washing your hands or using hand sanitizer (and might be easier to do often when sitting in your seat on the plane; it might also dry out your hands less)

benwr 3 Mar 2020 21:14 UTC
3 points

in reply to: Ben Pace’s comment on: How to fly safely right now?
Another thing you might want to bring: swimming or safety goggles. Iiuc, it’s possible for viruses to spread via your conjunctivae (although this is probably a much smaller effect than transmission via nose or mouth).

benwr 3 Mar 2020 21:11 UTC
1 point

in reply to: Ben Pace’s comment on: How to fly safely right now?
Re facial hair: it’s recommended not to have facial hair when wearing a face mask, because it makes the seal weaker. Do you think the protective effect is larger than that effect?

benwr 3 Mar 2020 21:09 UTC
3 points

in reply to: Ben Pace’s comment on: How to fly safely right now?
You can buy bottles for arbitrary gels, and then put hand sanitizer in those bottles.

benwr 1 Mar 2020 23:01 UTC
5 points

in reply to: benwr’s comment on: Coronavirus: Justified Practical Advice Thread
A thing I probably haven’t thought enough about is, “how much this will impact your rate of copper ingestion, and is that very bad?” My guess is that this is less important than the effects on infectious disease; it seems like it would need to increase your copper consumption by 100x in order to produce major negative health effects (https://www.atsdr.cdc.gov/toxprofiles/tp132-c2.pdf). I may try to be virtuous and do a fermi on this later but also I’d welcome someone else trying to do it.

Edited to add:

The most obvious effect of having too much copper is gastrointestinal distress. So if you try this and have stomach problems, maybe stop.

benwr 1 Mar 2020 8:00 UTC
3 points

in reply to: gwillen’s comment on: Coronavirus: Justified Practical Advice Thread
My plan is to use a reusable p100 mask, with copper tape on the structural components, hopefully forming a barrier between the external filters/valves and the internal surfaces, and then to wash my hands before / after wearing it. No idea whether this will be any good, but it seemed more workable / less potentially blameworthy than acquiring disposable masks in a shortage.

benwr 1 Mar 2020 1:32 UTC
29 points

on: Coronavirus: Justified Practical Advice Thread
Recommendation: cover the back of your smartphone in copper tape.

Reasoning: in addition to the reasoning for putting copper on all commonly touched surfaces, your phone is an especially good choice because of the “copper halo effect”, in which copper ions move from copper surfaces to nearby surfaces (like, say, your hands), leaving them much less hospitable to microbes. [Edit: As MalcolmOcean points out, this mechanism for the halo effect isn’t supported by the Wikipedia page below. I made a leap to this explanation without realizing it. That said, I do think that copper (and copper oxides) will get on your hands as a result of this tape, partly because I’ve seen my hands turning a bit blue.]

https://en.m.wikipedia.org/wiki/Antimicrobial_copper-alloy_touch_surfaces

A downside is that your hands may turn slightly blue. [Also: See the comment below about uncertainty about how much copper you’ll eat as a result of this; tldr: I don’t know but I think it’s probably fine]

[This is a signal boost for Lady Jade Beacham’s response to Connor_Flexman, but the idea was originally introduced to me by James Payor]

benwr 27 Jan 2020 7:27 UTC
1 point

in reply to: Bob Jacobs’s comment on: Is the Reversal Test overrated?
I think the main difference between the marginal reversal test and how I read your post is just the magnitude of the change. For the marginal reversal test to make sense, I think the change needs to be small relative to “typical” values of the parameter. So, changing life spans by months rather than years, or changing body temperature by single degrees.

And yeah, I think that the counterfactual reversal test is much more of a heuristic than a careful argument, but it does seem useful as a way of disentangling disagreements, especially with sufficiently thoughtful interlocutors.

benwr 27 Jan 2020 7:22 UTC
1 point

in reply to: Raghu Veer S’s comment on: Is the Reversal Test overrated?
I meant the first thing, sorry for lack of clarity

benwr 25 Jan 2020 19:41 UTC
20 points

on: Is the Reversal Test overrated?
I think that neither of your examples is correctly using the reversal test. IMO, two different versions of the reversal test are useful: the marginal reversal test, and the counterfactual reversal test.

Marginal version: “So you don’t think that increasing your body temperature a small amount is good—do you think decreasing it a small amount would be good? If not, can you explain why your current state is optimal?”

Counterfactual version: “So you don’t think that increasing your body temperature by 50 degrees would be good? Would you still think that if your body temperature had always been 50 degrees higher, and we were talking about decreasing it 50 degrees?”

I think in both cases the reversal tester correctly loses the argument. I also think that they both do a good job of helping to decide where to find the interesting bits of argument.

benwr 4 Dec 2019 9:23 UTC
1 point

on: benwr’s Shortform
I made a blog because I didn’t know where else to write gushing reviews of things. I haven’t written anything there yet, but soon I hope to have written up some of the following:
- An account of what I’ve learned since getting mildly fixated on pumping CO2 out of my bedroom
- A gushing review of my iPad Pro 11” with Apple Pencil
- A mostly-gushing review of my Subaru Crosstrek
- A gushing review of my bed and mattress
- A gushing review of the-general-excellence-of-fast-food-franchises
- A post about how I feel a lot of internal tension about consumerism

benwr 4 Dec 2019 9:17 UTC
1 point

on: benwr’s Shortform
I’ve recently been thinking a lot about pumping CO2 out of my bedroom. By coincidence, so has Diffractor (in a slightly different context / with different goals). His post on the CO2 scrubber he built is a pretty good read, although I think he might be making a mistake about the plausibility of vacuum swing adsorption using zeolites. I wrote a comment outlining what I think is the mistake, and I guess I wanted to highlight it here in case I later want to come back and find it, and because I want more people to see it and potentially write dissenting opinions.

https://www.lesswrong.com/posts/G4uMdBzgDsxMsTNmr/co2-stripper-postmortem-thoughts#eoMLeSXYM4kwk68ix

benwr 4 Dec 2019 8:44 UTC
4 points

in reply to: cousin_it’s comment on: CO2 Stripper Postmortem Thoughts
Because the air you breathe out has much more CO2 by volume than the air you’re processing (it diffuses quickly). See my comment elsewhere for a potential way around this, though.

benwr 4 Dec 2019 0:59 UTC
3 points

on: CO2 Stripper Postmortem Thoughts

Adsorption onto zeolites is also plausible, but the issue is that it requires alternately exposing the zeolites to high air pressure and low air pressure, and high airflow is required. We can idealize a perfect CO2 stripper as a magic box that inhales air and spits it out at 0 ppm. If you want a steady-state concentration of 500 ppm for 2 people, then we can see how much air-flow is required to lock up 2 kg of CO2 in 24 hours. This comes out to about 100 cubic feet per minute. This is the bare minimum air flow for any CO2 stripper, but in this particular case, it corresponds to a 25 horsepower air compressor, which is 18 kilowatts.

I’m not sure this is as much of a barrier as it sounds, at least if you have access to a window you can vent to. Imagine if I had a membrane that let only CO2 through, and a 50-micron vacuum pump (typically ¹⁄₂ HP). I could pump CO2 out of the room about as fast as the CO2 would diffuse across the membrane. In this setup, the amount of gas pulled out would be pretty tiny, because you’d be pumping only the CO2, but the effective amount of air being processed would be quite large.

So if you have a vacuum swing adsorption machine, with some zeolites in an array of mixing chambers, that can be alternately mixed with the air in the room and then evacuated outside, what matters is the equilibrium adsorption of each component of air, and the speed of adsorption / desorption. The air mixing can be done with a simple fan (providing the effective high volumes of air processing).

That said, there are other major problems with zeolites. The main one I’ve been struggling with is that zeolites really love to adsorb water vapor, nearly as much as CO2, and there’s a lot more water vapor than CO2 in the air. Competition for adsorption sites isn’t well-understood, but one study shows that water vapor in the air seriously decreases the amount of CO2 adsorbed. This also means that the system described above would function as a dehumidifier as much as a CO2 pump.

[epistemic status: very uncertain; writing as though I were more certain because I think it’s more fun / engaging]
What links here?
- benwr's comment on benwr’s unpolished thoughts by benwr (4 Dec 2019 9:17 UTC; 1 point)

benwr 18 Oct 2019 21:49 UTC
3 points

on: The best of the www, in my opinion
My list is similar but also includes
- The Online Etymology Dictionary
- Wikipedia, obviously
- nLab
- squares.io, possibly the most wholesome website I’m aware of
- Meteuphoric
- Lobste.rs
- Better Explained

benwr 8 Sep 2019 18:06 UTC
5 points

on: benwr’s Shortform
Doom circles seem hard to do outside of CFAR workshops: If I just pick the ~7 people who I most want to be in my doom circle, this might be the best doom circle for me, but it won’t be the best doom circle for them, since they will mostly not know each other very well.

So you might think that doing doom “circles” one-on-one would be best. But doom circles also have a sort of ceremony / spacing / high-cost-ness to them that cuts the other way: More people means more “weight” or something. And there are probably other considerations determining the optimal size.

So if you wanted to have a not-at-the-end-of-a-workshop doom circle, should you find the largest clique with some minimum relationship strength in your social graph?

benwr 7 Sep 2019 0:56 UTC
5 points

on: benwr’s Shortform
Yet another Shortform-as-feature-request:

Notifications and/or RSS feeds from particular posts’ comments / answers.

This would be especially useful for Questions and Shortform posts (sometimes tellingly mis-labeled “shortform feeds”), both of which are things where one particular post has a collection of related comments, and which gather content over time.

I currently subscribe to the front page in Feedly, and whenever someone asks a question that I find interesting I mentally cringe because I know that I’ll have to remind myself to check back (and I probably will never actually check back).

I guess I could come up with some custom Zapier / IFTTT system for this if I spent a few hours on it, but I suspect this would be generally useful functionality.