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Comment by dhabxkxbx | Hacker News Reader

What does “Burn” mean?

Break the bonds of just about anything except fluorides and metals? Probably.

Deposit enough energy I locally heat the material above it’s auto ignition T? Well that’s a flux question

This looks like a great HN comment, but could you please stop creating accounts for every few comments you post? We ban accounts that do that. This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.

HN is a community and we want it to remain one. For that, users need some identity for others to relate to. Otherwise we may as well have no usernames and no community, and that would be a different kind of forum. https://hn.algolia.com/?sort=byDate&dateRange=all&type=comme...

You needn't use your real name, of course.

“ This looks like a great HN comment, ”

Thank you. I thought it was rushed w/out the explanation that it deserves (it has fascinating implications about the lack of the color blue in nature). Also, I felt it came out as snarky or arrogant, which I didn’t intend. But I was juggling other things :S

Unfortunately, I’m afraid you’ll have to ban me. I’ve abused the site far too long but I also have no intention to expose myself w/ a profile (any user with a karma > 1000 is trivial to dox).

> any user with a karma > 1000 is trivial to dox

How so?

Can you elaborate? Detach to another thread maybe?

I think you are fighting an uphill battle there. HN is a community, yes, but one with a heavy pro-privacy slant. There's always been a disconnect between that and the admins' values who have always opposed adding the ability to delete anything, not even usernames on comments. Rotating usernames is a predictable consequence of not being able to delete anything, even superficially (and much more effective).

We delete comments and rename accounts for people every day. We just don't offer it wholesale. No one asks for help with that gets turned away, nor, I believe, has anyone gone away unsatisfied. Maybe I'm forgetting one or two.

We care a lot about individuals' need for privacy. We just need to balance it with the community's need to preserve its archive, and the right of repliers not to have the context of their comments pulled out from under them. We bend over backwards to get that right. For example, I have written custom code to help individual users with complex requests on several occasions.

I should probably add this to the FAQ.

It's okay to have an alt account, you just shouldn't create a new alt account for every new comment. This allows for their moderation systems to be effective.

My account is a great example. This account is separate from my real identity, and I use it to post about things I don't want associated with my real identity. I went through a period of poor-quality commenting that led to well-justified moderator action against it(I'm not exactly sure what, but I'm consistently brought to the bottom of threads). This is important for the site because it helps maintain a good signal-to-noise ratio and keep the site interesting and productive. If I were to always create a new account, it would bypass this important moderation tool. Reputation is important in any community, including this one.

It's result of frequent shadowban without reason.

We don't shadowban accounts that have significant history on HN. We tell them why we've banned them: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&qu...

We use shadowbanning when accounts don't have much history and there's evidence of prior abuse. There's more explanation at https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que... if anyone wants it.

It's not true.

If it weren't true, people would be jumping in with counterexamples all over the place and we'd never hear the end of it.

If you know of a counterexample, you should state what it is so readers can make up their own minds. Also, it's possible that we made a mistake, in which case a link would be helpful so we can correct it.

It's also possible that there were complicating factors. We've dealt with thousands of these cases. There's no easy formula for summing them all up. But the principles I just described here are certainly the ones we apply and the ones that we teach to moderators.

Yes, to raise the temperature of a material in which ignition can occur.

I know the cheap hobby laser machines use a 405-450nm module, which works decent on stuff like wood. Now since it's about half the wavelength, is it more affective in cutting / etching these materials with a lower optical output power.

If you look at CO2 lasers, at 40W ($350 on eBay) you can cut plywood, at 150W ($5000 on eBay) you can cut metal. Both of those are 1040 nm.

The 450 nm modules you can get up to 5W ($100 on eBay), but those can hardly cut anything, they're more like engravers.

CO2 lasers are typically at 10.6 microns. They can cut metal but you need at least 100W and RF pumping. Metal-cutting lasers are more commonly fiber lasers with wavelengths of ~1050nm.

That's just straight up energy transfer. Doesn't matter exactly what wavelength you use provided you dump enough energy in, and this one is so inefficient it doesn't make sense.

“ is it more affective in cutting / etching these materials with a lower optical output power.”

Probably because it’s more likely to be absorbed.

On the other hand, absorption can’t be > 100%. So a longer wavelength laser an cut just as well for the same power as long as the mtls absorbs all the photons

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