HNHacker News
TopNewBestAskShowJobs

ucha

2,705 karma · joined October 22, 2012

Quant trader. Former software engineer. Mathematician by training.
submissionscomments
ucha··on Germany's Energy Catastrophe
> On sustainable energy sources: I, as many other germans, receive all of my electricity from purely renewable energy sources for more than ten years now. 24/7.

How can you receive energy purely from renewable energy sources when the wind doesn't blow and the sun doesn't shine? Germany doesn't have any significant capacity for electricity storage. It's such a bold statement but it seems physically impossible.

ucha··on Germany's Energy Catastrophe
1. Your article on nuclear energy just says that France has reactors that need maintenance. It also says they produce less electricity because they need cold water which is not currently available because of heat waves and droughts. Both are temporary problems that can be planned around or avoided by over-provisioning capacity. As the original article notes, you cannot over-provision capacity with renewable energies because they tend to produce 100x less power on windless or cloudy days.

2. It's more efficient to burn gas and collect the heat for industrial processes that go through an intermediary step of converting heat into electricity. I don't think it has anything to do with gas being irreplaceable as a source of heat. Gas can be necessary as a chemical precursor in some reactions - which can't be replaced by electricity - but that has nothing to do with heat.

ucha··on The Spanish PM and the defence minister were infected by Pegasus (in Spanish)
Morocco bought Pegasus and they've quite frequently entered in diplomatic spats with Spain over the last few years over the disputed Sahara.
ucha··on Apple unveils contactless payments via Tap to Pay on iPhone
EDIT: thanks everyone for quickly correcting my mistake, I missed the part that explained that more forms of contactless payments would be accepted

I don't really understand why a merchant would use this feature.

If you already use a PoS, why would you replace it with another one that only supports customers who own an Apple device?

If you accepted only cash, maybe it's a small improvement because you can use your existing iPhone if you had one to accept cashless payments from Apple customers...

Does Tap to Pay only make sense in the second case or am I missing something?

ucha··on Europe Is Losing Nuclear Power Just When It Needs Energy
It wouldn't wipe out Europe but make uninhabitable due to nuclear fallout. Same as the exclusion zone near Pripyat. https://historyofyesterday.com/the-real-life-suicide-squad-w...
ucha··on Europe Is Losing Nuclear Power Just When It Needs Energy
Uh that makes no sense.

> If it was true, don't you think every single country in the world would obtain such a world-destroying weapon?

Countries already have nuclear weapons. They can very well spread radioactive material over large landmasses but what's the point?

> If it was true, then a single nuclear reactor would be able to power the whole world for eternity

I have no idea how you deduced this but it's wrong.

ucha··on Europe Is Losing Nuclear Power Just When It Needs Energy
Nuclear is obviously key to energy independence etc... but the very common take these days of "Nuclear power is the safest energy production technology available, just look at historical data" is deeply misguided.

It's very hard to accurately estimate the risk of a nuclear power-plant disaster because looking back at the past and extrapolating data from there is non-sensical when the risk is so fat-tailed. Sure, Chernobyl, Fukushima and ever Three Mile Island killed a few thousands at most in aggregate but for anyone familiar with the history of Chernobyl, the story is quite different.

10 days after the main explosion, a leak caused a large amount of water to accumulate under the melting core. Had the melting core reached that pool of water, it would have caused a massive steam explosion that would have spread radioactive particles over most of Europe and Russia making them uninhabitable. Thankfully, three men risked their lives to enter the power-plant and closed a valve preventing more water from accumulating under the core.

Now, you could say that current reactors are safer, which might be true, but before Chernobyl, such a disaster was also thought to be impossible. Even if there is a 10% risk of contamination of a whole continent over a century, does it make sense to take it? One could argue that such risk would be acceptable if it prevents climate change. But acknowledging the existence of these enormous risks is a required step to have an honest debate.

ucha··on Ivermectin Prophylaxis Used for Covid-19
The best meta-study review of Ivermectin I've seen was done by Scott Alexander [0]. He individually reviewed a few dozen studies. His take was that Ivermectin is an effective dewormer that is useful as a prophylactic when people are widely exposed to worms. Because they don't catch worms, they're in better shape to fight Covid when infected. However Ivermectin has no effect in most developed countries where the general population isn't subject to worm infections.

[0] https://astralcodexten.substack.com/p/ivermectin-much-more-t...

ucha··on The Coinbase model: profit from the crypto assets it lists
Non-paywalled: https://archive.ph/6eiAh
ucha··on Germany is closing half of its reactors before the end of the year
I understand that energy consumption includes things that aren't electricity so the proportion of oil is higher but everything else is different too. For example, in the parent comment, more wind than biomass is produced but in this comment the consumption is the other way around. Is it because biomass is used for cars as well (ethanol)? Maybe wood for heating too?
ucha··on Why Bitcoin is worse than a Madoff-style Ponzi scheme
This argument is so basic yet it keeps being repeated over and over on HN...

It boils down to you can't expect a return on bitcoin hence it's shouldn't be worth anything. If that argument was true, then gold is a ponzi that shouldn't be worth anything and the same would apply to art.

A slightly more advanced rebuttal would be to say, yes but gold has some industrial use and you pay for art because you can enjoy consuming it. But the price of gold and rare artistic pieces is many times their "useful value" if defined as such.

All these arguments show a deep misunderstanding of what constitute money, the history of money [1] and the concept of "hard money". Bitcoin is the only way to transfer an arbitrary amount of money in a way that is fast, verifiable, permissionless and to an arbitrary location. This particular use, that no other tool makes possible, means it has some value to some people and consequently should be worth something. The question of what its fair value is harder to answer but just because gold is worth more than its industrial value doesn't make it a ponzi scheme.

[1] https://econwpa.ub.uni-muenchen.de/econ-wp/eh/papers/0211/02...

ucha··on Moderna booster increased neutralizing antibody levels against Omicron ~37-fold
This is true in theory but I don't think it matters in practice. Median time between symptoms onset and death is 7 days for the 2nd wave in the UK [1] which is pretty short and doesn't allow for "old seeds". The tail of distribution is also quite thin. Those number might be different for Omicron but nothing points to that as far as I know. Unless Omicron-sick people die on average 2 months after infection I don't see how it could be equally or more deadly.

[1] https://assets.publishing.service.gov.uk/government/uploads/...

ucha··on Moderna booster increased neutralizing antibody levels against Omicron ~37-fold
South Africa has 20,000/day cases which is about the same they had in July, yet they peak at 30 deaths/day vs 400 deaths/day in July. To estimate the fatality rate of a variant, you need to do it within the same population. At the current rate, Omicron is literally as deadly as influenza in South Africa [1] and, as the current wave passed its peak, it might be even less deadly than that.

PS: parent post is sarcastic

[1] https://www.cdc.gov/globalhealth/countries/southafrica/what/...

ucha··on IBM and Samsung Unveil Semiconductor Breakthrough
Not really.

If operational expenditure decrease while capital expenditures stays constant, it could still cost the same amount of money to mine but use less electricity. A miner pays both for power and the mining rigs.

ucha··on Acquisition of chess knowledge in AlphaZero
After watching some of the games AlphaZero played against Stockfish, I have to say I don't really agree that the moves make sense to a grandmaster... AlphaZero has this uncanny ability to sacrifice many pawns to restrict the movement of the opponent's pieces, something that you might see in advanced play but nowhere near the extent you see it with AlphaZero. Many more of the moves it plays are hard to make sense of compared to a classic engine such as Stockfish.

See GothamChess' very entertaining analysis: https://www.youtube.com/watch?v=8dT6CR9_6l4

ucha··on Kape Now Owns ExpressVPN, CyberGhost, PIA, Zenmate, and VPN “Review” Sites
You're absolutely right! I could be paid to recommend Mullvad and my praise of it should be taken with a grain of salt!

The point I was trying to make is that it is not a small provider, it is well rated by reputable privacy reviewers such as privacytools.io - who do not use affiliate link or take payment from providers - so there is no reason it should be ignored by Sven Taylor. I'm less trying to praise this particular VPN than to show that that review website is somewhat "provably" an affiliate link farm.

ucha··on Kape Now Owns ExpressVPN, CyberGhost, PIA, Zenmate, and VPN “Review” Sites
I don't know how accurate your ranking method is - NLP is tricky - but the idea is very very cool!
ucha··on Kape Now Owns ExpressVPN, CyberGhost, PIA, Zenmate, and VPN “Review” Sites
Yet Sven Taylor recommended ExpressVPN for years despite the fact that its ownership was quite suspect (secret). We've never fully known who was behind it and from where it was truly operated.

The ranking of best VPNs on the site is mostly a ranking of VPNs that offer the largest referral fees [1].

One of the largest, most honest and transparent VPN, Mullvad, does not have an affiliate program. And guess what, it's not even reviewed on Restore Privacy!

[1] https://onemorecupof-coffee.com/best-vpn-affiliate-programs/

ucha··on Pandora Papers: is the world’s biggest leak the world’s biggest cover-up?
I don't know what he's talking about when he says that only 1% of the ICIJ gets is made public. They published everything they had from previous leaks as far as I know. See here

https://offshoreleaks.icij.org/

The current data leak is a bunch of unprocessed files and emails that would be irresponsible to leak as it could contain private information such as passport scans of no public utility. They said they are in the process of cleaning that data to later make it available.

ucha··on SEC charges Netflix insider trading ring
This is the most important question IMO.

However, I'm not sure they do have that information. I would speculate that the number of people who make large option bets before earnings correctly on the same stock over multiple quarters should be zero and if it is very small, it is worth investigating. If they see that a subset of traders is 3 people with Korean names, that would immediately suggest that something is wrong...

ucha··on Software Engineering Salaries in Europe vs. the United States
Salaries don't tell the whole story for an employer because you have to pay many more charges on top of the salary. For example in France, the "charges patronales" are about 60% of the salary before taxes. In the UK, the National Insurance contribution for the employer are lower but it's always higher than in the US if I remember correctly. When I compared hiring in France vs the US, the cost was just slightly lower in France but not by the amounts shown here.

For the employee, the salary is obviously much lower than the US but then they also don't have to save for uni, medical care, retirement etc...

ucha··on Software Engineering Salaries in Europe vs. the United States
Cache: https://web.archive.org/web/20210803233854/https://4dayweek....
ucha··on Costa Rica signs law to attract digital nomads
It's easy for someone who's not tax resident to pass a non-tax residency test? Isn't that a tautology? ;)

Your understanding of what is a family test isn't correct either. If you have a boyfriend/girlfriend and you spend enough time together, you will be considered as "living as spouses or civil partners" and that would prevent you from passing the family test. The burden of proof would be on you to prove you that you're not that close to your partner to pass the test. And by the way, if your bf/gf owns or rent a place in the UK in which you spent a single night, HMRC would consider you have an accommodation in the UK.

There are solicitors who make a living solely on individual tax residency because it is way more complex than spending >183 days in the UK.

ucha··on Costa Rica signs law to attract digital nomads
Not really, if you spend 120-183 days in the UK, to not be a tax resident, you'd need to not have family there, not have a house/hotel for more than 90 days, nor work there for more than 40 days, nor have spent more than 90 days there the year prior and you'd need to have spent more time in another country. It's a lot of conditions!
ucha··on Costa Rica signs law to attract digital nomads
It's even more particular, but in practice, it does affect a lot of funds, if not a lot of people - which is why they legislated. One can move to a no/low tax jurisdiction and not be a Spanish tax resident as long as they're covered by a double taxation agreement.
ucha··on Costa Rica signs law to attract digital nomads
That's not true. If you have an apartment in Croatia, or if your family lives in Croatia, you are a tax resident in Croatia even if you don't spend a single day there.

https://www.oecd.org/tax/automatic-exchange/crs-implementati...

ucha··on Costa Rica signs law to attract digital nomads
"Taxpayers liable to PIT:

Individuals of Spanish nationality who accredit their new fiscal residence in a country or territory labelled as a tax haven will not lose their status as taxpayers for Individual Income Tax. This rule is of application during the tax period in which the change of residence occurs and for the next four tax periods."

https://www.oecd.org/tax/automatic-exchange/crs-implementati...

ucha··on Costa Rica signs law to attract digital nomads
Not true.

https://www.gov.uk/government/publications/rdr3-statutory-re...

ucha··on Costa Rica signs law to attract digital nomads
Tax residency is a very complicated matter but in general, you do not loose tax residency 183 days after leaving.

In Spain, it takes 5 years before losing tax residency after you've left the country. In France, having your wife and children in France makes you resident even if you don't live there. In the UK, you can be resident by only spending 15 days in the country if some other conditions are met.

On top of that you have to add the interaction between national law and double taxation agreements between countries.

ucha··on Wealthy people are renouncing American citizenship
Being a citizen of Cyprus gives him visa free travel and work options in Europe. As he hasn't renounced US citizenship, he certainly isn't taking advantage of that for tax reasons. The article seems to imply otherwise, but that's basically what bad journalism is... strongly suggesting an incorrect interpretation of facts while still "telling the truth".
← PreviousPage 2 of 10Next →