patall (u/patall) - Readit News

patall commented on SpaceX's giant Starship Mars rocket nails critical 10th test flight space.com/space-explorati... · Posted by u/mpweiher

mchusma · a day ago

Love it, great job SpaceX!

I watched the Martian again the other day and I marveled about how much has changed. With Starship progress, almost none of the plot really makes sense (bespoke vehicles and payloads etc). The first mars expeditions will probably be stocked with a thousand tons of gear, enough to easily last a guy 5 years. And if some dude were stranded on Mars, SpaceX could start lobbing things in his direction within maybe 30 days?

The Martian is a vision for a 2035 mission from 2011. We seem likely to beat that!

patall · a day ago

> SpaceX could start lobbing things in his direction within maybe 30 days?

If Earth and Mars are on opposite ends of the sun, nobody is going anywhere within 30 days. I do not see how anything will change from the one transfer window per ~2 years for the foreseeable future

patall commented on Deep-Sea Desalination Pulls Fresh Water from the Depths scientificamerican.com/ar... · Posted by u/noleary

sikonomial · 12 days ago

The container doesn't have to float. The container could have density of 1020.00001kg per m3 and it will sink. Saltwater is 1020kg per m3

Then when you fill container with fresh water 1000kg per m3 it will float.

patall · 12 days ago

I think I see what you do not understand. Your freshwater is at surface pressure, not at depth pressure. You cannot just displace the salt water from your container, you need pressure to displace the saltwater and put the freshwater out of the filter chamber and in the container. That does not just happen because you cannot do it in the filter chamber as else, that filter chamber would lose its pressure differential and not work anymore. Sorry, but your idea is not made for reality :)

patall commented on Deep-Sea Desalination Pulls Fresh Water from the Depths scientificamerican.com/ar... · Posted by u/noleary

sikonomial · 12 days ago

The process would be like this:

1. Take in salt water

2. Spend some energy to separate salt from water.

3. Put fresh water into a container.

4. The container containing fresh water will raise to the surface, since it is less dense than salt water.

There is no perpetual motion.

patall · 12 days ago

Then you could also do it at the surface. But they do it a depth because they want a pressure difference on the two sides of the osmosis membrane. You somehow need to generate that pressure difference and the energy you need for that is minimum equal to the amount you need to move the freshwater.

Oh, and you will have to do it continuously, not with a 'container'. Existing desalination plants produce hundreds of thousands of cubic meters of fresh water per day.

patall commented on Deep-Sea Desalination Pulls Fresh Water from the Depths scientificamerican.com/ar... · Posted by u/noleary

dan353hehe · 13 days ago

I think the claim about higher efficiency is due to the fact that the sea temp is stable and they don’t have to deal with algae blooms at the bottom of the ocean.

I don’t see how taking advantage of the pressure at lower depths makes much sense. The water would still need to be pumped to the surface, which I think would take as much energy as just pressurizing it.

Did I miss something?

patall · 12 days ago

It's not the pressure difference that other comments write, that does not make sense.

I would assume it's the result to waste water ratio. Afaik, reverse osmosis produces 3 to 4 litres of waste water per liter of fresh water. Since you do not have to pressure the waste water, only depressure the fresh water, you save energy.

patall commented on Deep-Sea Desalination Pulls Fresh Water from the Depths scientificamerican.com/ar... · Posted by u/noleary

sikonomial · 12 days ago

You don't need to pump up the water. Fresh water is less dense than salt water so it will float up to the surface on its own.

patall · 12 days ago

That would be a perpetuum mobile. You either have a pressure difference at the membrane or between outside and inside the tube.

patall commented on Irrelevant facts about cats added to math problems increase LLM errors by 300% science.org/content/artic... · Posted by u/sxv

aflag · a month ago

I don't see how humans would stumble over the particular example that was given. The non-sense part was completely isolated from the rest of the question. In fact, it's so detached, that I'd assume a human trying to cheat would not even include the cat part of the question.

patall · a month ago

Without any context? Without: 'haha look, AI is easily distracted'. Without: 'Can you please answer this question'. Just the text?

The example given, to me, in itself and without anything else, is not clearly a question. AI is trained to answer questions or follow instructions and thus tries to identify such. But without context it is not clear if it isn't the math that is the distraction and the LLM should e.g confirm the fun fact. You just assume so because its the majority of the text, but that is not automatically given.

patall commented on Irrelevant facts about cats added to math problems increase LLM errors by 300% science.org/content/artic... · Posted by u/sxv

Xss3 · a month ago

Humans do not stumble over this. Did you read the article?

They present a normal maths problem then add a random cat fact to the end or the start. Humans dont struggle with that...

patall · a month ago

Print out only the text and hand it, without any context, to a random other human and look what happens. I highly doubt that more than 25% will answer the question, and not because they are incapable of answering it.

What you forget is that you have context. Like: 'Look, LLMs are not able to answer this question!'. While you post the text without any context to the LLM.

patall commented on Irrelevant facts about cats added to math problems increase LLM errors by 300% science.org/content/artic... · Posted by u/sxv

patall · a month ago

I am ambivalent about these kinds of 'attack'. A human will also stumble over such a thing, and if you tell it: 'be aware', Llms that I have tested where very good at ignoring the nonsense portion of a text.

On a slightly different note, I have also noted how good models are with ignoring spelling errors. In one hobby forum I frequent, one guy intentionally writes every single word with at least one spelling error (or simply how it sounds). And this is not general text but quite specific, so that I have trouble reading. Llms (phind.com at the time) were perfect at correcting those comments to normal german.

patall commented on Return of wolves to Yellowstone has led to a surge in aspen trees livescience.com/animals/l... · Posted by u/geox

thom · a month ago

Not sure where opinion ended up on this, are there dissenting voices still?

https://www.accuweather.com/en/weather-news/scientists-debun...

patall · a month ago

Because data it is inconclusive. I.e this publication that says that the impact of wolves is beyond their population pressure, reducing traffic accidents by making deer more wary:

https://www.pnas.org/doi/10.1073/pnas.2023251118

patall commented on I wrote my PhD Thesis in Typst fransskarman.com/phd_thes... · Posted by u/todsacerdoti

aitchnyu · 2 months ago

Tangential, do LLMs pick up new languages that have less internet discussion and which develop rapidly after knowledge cutoff dates? To naysayers, AIs are supposed to generate hands with 6 fingers and ossify language and framework versions.

patall · 2 months ago

Maybe if it's completely distinct. Else definitely no, unless, maybe, if the model is fine-tuned. Had a discussion about it with my dad whos work is developing in a non-mainstream SmallTalk dialect where it doesn't work at all.

u/patall

KarmaCake day1651April 12, 2016View Original