timmaxw

> First very simple point, to become insolvent you have to actually take a loss somewhere. They may have a lot of junk tokens on their balance sheet, and these tokens may be overmarked, but Alameda's cost basis (most of them were from seed rounds) is still way below their current value.

Hypothetical scenario: Alice invests $100M in seed rounds for a bunch of tokens. The token values go way up, and the holdings are nominally worth $14B. Alice borrows $7B in real dollars. Alice loses those real dollars on other bets. The nominal value of the tokens is still $14B, but Alice can't actually liquidate them for $7B in real dollars. So Alice is functionally unable to pay back the loans.

So Alice took a loss somewhere (on the other bets) and is effectively insolvent, but you can't assess that just by looking at the cost basis of the tokens that Alice still holds.

(I don't know if this actually describes Alameda; it's entirely possible that Alameda's loans are token-denominated as you're saying, in which case Alameda would be solvent. I'm just pointing out that it's more complicated than just looking at the cost basis.)

> What do you do about all the scattered light?

I think it's actually fine. Quick back-of-the-envelope calculation:

- The lens collects about 1 m^2 of sunlight.

- At the focal point, the concentration is way higher than sunlight.

- But when the light is scattered away from the focal point, it's distributed over an area of ~4 pi R^2.

- So from the point of view of a person looking out the window, R^2 would be much greater than 1 m^2, so the crucible would be less bright than the outdoor sun.

- The outdoor sun doesn't blind people unless they look directly at it, and humans are good at avoiding that.

So I think the crucible would appear as an annoying glare that people would instinctively look away from, but it probably wouldn't accidentally blind people.

> Until someone can demonstrate that this is an actual problem, I will believe it to be a fake problem

If a payment processor suspects money laundering, it's illegal for them to tell the business that. Under anti-money-laundering legislation, this is considered a crime called "tipping off": https://onlinelibrary.wiley.com/doi/10.1002/9780470685280.ch...

(Disclaimer: Used to work at Stripe, but not on this particular area. Not an expert on either the law or Stripe's policies.)

If a payment processor suspects a business is laundering money, they can hold the funds, but it's illegal for the payment processor to tell the business that they suspect money laundering. So they end up saying something like "we're holding your funds for vague unspecified reasons".

(Disclaimer: Used to work at Stripe, but not on this particular area. Not an expert on either the law or Stripe's policies.)

I don't know about Burry, but Nate Silver has been right more than just once! https://projects.fivethirtyeight.com/checking-our-work/ is a statistical analysis of 538's track record in forecasting elections going back to 2008. The analysis shows that 538's predictions are generally pretty well-calibrated, in the sense that e.g. if there were 100 races where 538 predicted "Democrats have a 70% chance of winning this race", then the Democrats did actually win about 70/100 of those races.

I haven't found this to be a problem in practice. I have two USB-C laptops -- a ThinkPad T480s and a MacBook -- and both of them work fine with my USB-C dock, and with each others' chargers. That's all I need.

Nice! Yeah, mCaptcha looks like just what I had in mind.

I wonder why this approach hasn't been widely adopted?

I wonder if proof-of-work would help. Suppose every form submission requires an expensive calculation, calibrated to take about 1 second on a typical modern computer/smartphone. For human users, this happens in the background, although it makes the website feel slower. But for bots, it dramatically limits how many submissions each botnet host can make to random websites.

I love this!

Will it be possible to plot historical events on the map? I'd love to see e.g. a month-by-month combined timeline+map of Napoleon's invasion of Russia, or the D-Day invasion.

It would also be neat to be able to link a series of historical events into a sort of "guided tour", to make the events discoverable and put them in context.

> AFAIK no laptop supports both modes

Are you sure? From what I've seen, it seems common for laptops to support the combination of Thunderbolt and DisplayPort Alternate Mode. (Both my MacBook and my Thinkpad T480s have ports like this.)

I found this page helpful: http://www.canoncat.org/canoncat/onlinehelp.html

Shadowstats's 80s-based measure says we've been having 10% YoY inflation for two decades now. If that were true, prices would've 5x'ed since the year 2000. That doesn't pass the 'sniff test' to me; e.g. the Big Mac Index [1] says a Big Mac cost $2.50 in 2000 and $5.50 today, equivalent to about 4% YoY inflation.

[1] https://www.economist.com/big-mac-index

These aren't dead voters, they're living voters who happen to have the same name and birth month/year as a dead person.

As evidence: I spot-checked three random entries. In all three cases, I could find a Whitepages.com entry for a person with the same first & last name, in or near the zip code where the ballot was for; but the obituary was for a different city.

Entry 962: The voter is registered in zip code 48602 (Saginaw, MI). Whitepages.com lists a resident of Saginaw, MI with the same name and age as the voter. But the obituary is for someone who lived in Eastpoint, MI, which is 100 miles away. Howmanyofme.com estimates there are 6,000 people in the United States with this same name.

Entry 302: The voter is registered in zip code 48076 (Lanthrup Village, MI). Whitepages.com lists a resident of Southfield, MI (which is a city surrounding Lanthrup Village, MI) with the same name and age as the voter. But the obituary is for someone who lived in Detroit, MI, which is 17 miles away. Howmanyofme.com estimates there are 1,600 peple in the United States with this same name.

Entry 707: The voter is registered in zip code 48162 (Monroe County, MI). Whitepages.com lists a resident of Carleton, MI (a city in Monroe County, MI) with the same name and age as the voter. But the obituary is for someone who lived in Novi, MI, which is 48 miles away. Whitepages.com also lists at least three other individuals in various parts of Michigan with the same name and age range.

I've filed this as an issue on the Github repo: https://github.com/votesunshine/votesunshine.github.io/issue...

It's very irresponsible for you to be spreading these rumors. You should make it right by spreading the truth instead: go back to wherever you found out about this page, and let them know that it's actually just a case of different people with the same name.

Suppose you have a newsletter with 10,000 subscribers. You need to perform a proof-of-work the first time you send an email to each new subscriber; so, 10,000 proofs-of-work. Each proof-of-work costs $0.001. This adds up to a grand total of ten dollars.

Or, to put it a different way: $0.001 is very roughly equivalent to a few minutes of CPU time. So if you have a single-core server dedicated to running your mailing list, you can onboard several hundred new subscribers every day.

Remember, the sender only needs to pay the proof-of-work when someone first joins the mailing list and receives the initial message. So, I don't see how this will kill mailing lists at all.

Maybe I'm missing something, but none of these objections seem insurmountable.

> Mailing lists and other legitimate email uses would be affected

The receiving server could require proof-of-work for the first message from a sender to a given receiver, but not for subsequent messages. If spammers try to abuse this, it's easy for the user to click "block this sender"; if the spammer changes their sending address, they have to do a new proof-of-work.

> Requires immediate total cooperation from everybody at once

It could be introduced gradually: if a proof-of-work is provided, then the message is allowed to skip the spam filter. Small mailserver operators often have trouble with their messages being caught in spam filters by GMail and other large webmail providers; even if GMail alone started accepting proof-of-work, that would probably be enough to convince a lot of senders to start generating proofs-of-work, which would drive adoption.

> Lack of centrally controlling authority for email

This is no more difficult than any other backwards-compatible extension to an existing Internet standard.

> Public reluctance to accept weird new forms of money

OP's post didn't mention a weird new form of money. The original HashCash proof-of-work proposal included a weird new form of money, but it's easy to imagine a proof-of-work system that doesn't.

> Sending email should be free

Suppose the proof-of-work cost is calibrated such that it costs about $0.001 per email. That would be enough to destroy spammers' margins, but the vast majority of legitimate users wouldn't mind paying that.

> Ideas similar to yours are easy to come up with, yet none have ever been shown practical

I kinda see the point here... But I'd like to understand _why_ it isn't practical, because none of the arguments make sense to me.

Are you sure they're using contact tracing _apps_? The original tweet says:

> Minnesota Public Safety Commissioner John Harrington says they've begun contact tracing arrestees.

> "Who are they associated with? What platforms are they advocating for? ... Is this organized crime? ... We are in the process right now of building that information network."

I interpreted that to mean ordinary detective work. I don't see any indication that they're using data from COVID-19 contact tracing apps on arrestees' smartphones, which is what the Hacker News title seems to imply.

See my comment: https://news.ycombinator.com/item?id=21551082

For anyone who's interested in more detail:

This type of computer is also called a "parametron" (https://en.wikipedia.org/wiki/Parametron). A Japanese researcher named Eiichi Goto independently invented it around the same time as von Neumann, and developed it much further than von Neumann did, so the idea is more often associated with Goto than with von Neumann.

The basic idea is that if a nonlinear harmonic oscillator is driven at twice its resonant frequency, it will oscillate stably in either of two phases. The two phases represent "0" and "1". If the driving signal is switched off and on again, the oscillator will arbitrarily "pick" a phase to stabilize on. If it's exposed to an input signal from another oscillator as it's turning on, it will always pick the same phase as the input signal. This makes it possible to copy a "0" or "1" from one oscillator to another. If the oscillator is exposed to input signals from several other oscillators, it will pick by "majority vote". Finally, a NOT-gate can be built by inverting the signal polarity. This set of primitives is sufficient to build arbitrary logic gates and flip-flops.

Goto's paper has an excellent explanation and more detail:

Goto, E. (1959). The Parametron, a Digital Computing Element Which Utilizes Parametric Oscillation. Proceedings of the IRE, 47(8), 1304–1316. doi:10.1109/jrproc.1959.287195

(PDF available at https://sci-hub.tw/10.1109/JRPROC.1959.287195)

I went for a 4k 28" monitor because it has the same DPI as my 1080p 14" laptop screen, which is convenient when using them together.

The article notes that the LED "acts as a very low temperature object". I interpret this to mean "the LED radiates as though its temperature is lower", rather than "the LED radiates as though its emissivity is lower". In other words, AFAICT the effect can still exist even if the LED has 100% emissivity in both absorption and emission, which would make it a black-body. So the fact that the real LED's emissivity is not 100%, is not relevant to the effect. But we're splitting hairs here.

True, but the distinction is irrelevant in this case.

(Disclaimer: I have some background in physics, but I'm not an expert.)

I think the heat is transferred from the "computer" to the LED itself. So the LED itself heats up.

To go into a bit more detail:

All physical objects emit thermal radiation (a.k.a. black-body radiation [edit, not quite correct]). The hotter the object is, the more radiation it emits and the shorter the wavelength of the radiation. For "red hot" objects, the radiation is in the visible part of the spectrum; for room-temperature objects, it's in the infrared, so you can't see it, but it's still being emitted. If you put two objects of different temperatures next to each other, they'll both emit radiation and absorb each others' emitted radiation. The hotter one will emit more radiation than the cooler one, so there will be a net transfer of energy from the hotter one to the cooler one (normally).

But in this experiment, when the researchers run the LED in reverse, this somehow suppresses the LED's normal thermal radiation emissions. The "computer" continues to emit thermal radiation, which is absorbed by the LED just like normal. But the LED doesn't emit thermal radiation back to the computer (at least, not as much as it normally would). So even though the LED is hotter than the computer, the LED acts like it's colder for thermal radiation purposes. So there's a net transfer of energy from the cooler "computer" to the hotter LED.

Of course, this isn't a complete solution; you still have to do something about the heat once you've transferred it to the LED. The article doesn't address this part of the problem. But I speculate you could just attach a heat-sink to the LED. Heat sinks work better at higher temperatures, so the computer+LED+heat-sink solution would be more effective than a computer+heat-sink alone.

> using less electricity than the major credit card networks

I googled around for "Bitcoin vs. VISA energy consumption"; the only argument I found in favor of VISA using more is here [0]. This compares Bitcoin to the entire global banking system, including the cost of e.g. keeping the lights on at physical bank branches. It very approximately guesstimates that the entire global banking system requires ~100 TWh/year, compared to Bitcoin's ~30 TWh/year [1].

For comparison: all data centers worldwide combined use about ~400 TWh/year [2]. I very much doubt that the credit card networks account for 7% of all data center energy consumption.

[0] https://hackernoon.com/the-bitcoin-vs-visa-electricity-consu...

[1] https://arstechnica.com/tech-policy/2017/12/bitcoins-insane-...

[2] https://www.forbes.com/sites/forbestechcouncil/2017/12/15/wh...

Could you recover those nutrients when you convert the algae into diesel?

Google S2 (a square-based alternative to Uber's H3) works by projecting the surface of the sphere onto the surface of a cube, then subdividing each face of the cube. So there's still some distortion around the edges and corners of the cube, but nowhere near as bad as a naive longitude/latitude strategy.

One of the reasons I chose a USB scope is for the portability. Real scopes are too big to stuff in a backpack. I agree the calculation would be different without that.

I haven't gone far enough in electronics to run into limitations of the above equipment; I figure I'll upgrade when I need to.

As a hobbyist trying not to spend too much money, I ended up getting the following amateur-level equipment:

- Digilent Analog Discovery 2: Low-end 30MHz oscilloscope+function generator+logic analyzer controlled via USB. $279 (or $179 with student discount) I think of it as 'swiss army knife' of electronics: it's not as good as a real oscilloscope, function generator, or logic analyzer, but it does the basics of all those roles and fits in your pocket. http://store.digilentinc.com/analog-discovery-2-100msps-usb-...

- Xprotolab Plain: Same general idea as the Analog Discovery, but only $20 and therefore an order of magnitude crappier. Only 20kHz bandwidth. Suitable for an absolute beginner on a tight budget. http://www.gabotronics.com/oscilloscopes/xprotolab-plain.htm

- Extech EX330 multimeter: It's a multimeter, the most basic instrument you'll need. $53 on Amazon. I recommend getting some alligator clip probes; I find them much more useful than the pointy probes it comes with. https://www.amazon.com/gp/product/B000EX0AE4

Yes, if you send a write to a server that's not the primary then rethinkdb will transparently forward it to the primary.

Former rethinkdb developer here. Sharding and replication just work out of the box. Connect the servers to each other with "rethinkdb --join otherserver", then use the web dashboard or the client APIs to specify how many shards and replicas for each table. Send queries to any server in the cluster and they get routed automatically.

Here's a web app that gives a concrete example of an asymmetry in time arising from time-symmetric rules:

http://timmaxwell.org/pages/cellular-automaton/index.html

Each row of the grid represents the state of the universe at a certain "time". Given any two adjacent rows, we can compute the row above them or the row below them according to a predefined rule, which is symmetric in "time". So we randomly generate the two initial rows and then from there derive the rest of the pattern. However, by default the two initial rows are mostly empty, corresponding to a low-entropy initial state. From this initial state, applying the rule either forward or backward in time leads to states of higher and higher entropy. So the system exhibits "arrows of time" flowing from the low-entropy initial state forward and backwards in time to the high-entropy equilibrium states.