Horizon Worlds and the Metaverse were both pitched as a "social" platform. And this in itself is where I believe they went wrong. It fundamentally differs from my limited experience with VR and its potential. I see VR as an "anti-social" platform rather than a "social" one - and I say this in a good way.

When I put on a VR headset, its as if I am shunning my current world. The experiences I find valuable in VR are the ones that elevate that feeling - imagine watching a basketball game courtside, or watching NASCAR while floating right above the track, or watching a live concert happening halfway across the world, or VR tourism (visiting different places anytime you want, from some breathtaking angles - my most memorable experience of this was a video on Angel Falls https://www.youtube.com/watch?v=L_tqK4eqelA), or even the classics like playing VR games and watching movies. I believe that they should have doubled down on providing a much richer "anti-social" experience.

ChatGPT's code execution container contains 56 vCPUs!! Back then, simonw mentioned:

> It appears to have 4GB of RAM and 56 (!?) CPU cores https://chatgpt.com/share/6977e1f8-0f94-8006-9973-e9fab6d244...

I'm seeing something similar on a free account too: https://chatgpt.com/share/69a5bbc8-7110-8005-8622-682d5943dc...

On my paid account, I was able to verify this. I was also able to get a CPU-bound workload running on all cores. Interestingly, it was not able to fully saturate them, though - despite trying for 20-odd minutes. I asked it to test with stress-ng, but it looks like it had no outbound connectivity to install the tool: https://chatgpt.com/share/69a5c698-28bc-8005-96b6-9c089b0cc5...

Anyways, that's a lot of compute. Not quite sure why its necessary for a plus account. Would love to get some thoughts on this?

A bit tangential here, but I am really looking forward to 2035 for the public domain. A ton of culturally significant works seem to enter then - And Then There Were None, Gone with the Wind, The Wizard of Oz, Mr. Smith Goes to Washington, Batman (Detective Comics #27), Superman #1, Marvel Comics #1, and Tintin’s King Ottokar’s Sceptre.

https://en.wikipedia.org/wiki/2035_in_public_domain

Wikipedia also tells me that all of the 'life + 70" countries will have Ian Fleming's James Bond works in the public domain in 2035 as well.

Followed him a bit last year. A really sweet and enthusiastic person.

I have described it in the "Timer Modules" section:

> A natural iteration of this approach is to store timers in an ordered list (also known as timer queues). In this scheme, instead of storing the time interval, an absolute timestamp is stored. The timer identifier and its corresponding timestamp that expires the earliest is stored at the head of the queue. Similarly, the second earliest timer is stored after the earliest, and so on, in ascending order. After every unit, only the head of the queue is compared with the current timestamp. If the timer has expired, we dequeue the list and compare the next element. We repeat this until all the expired timers have been dequeued, and we run their expiry processing routines.

And then, I go on to talk about its runtime.

Truth be told, this is a chapter for my book on data structures and algorithms that I think are interesting and obscure enough that not many people talk about them. Its goal is not widespread practicality, but rather a fun deep dive into some topics.

Comments URL: https://news.ycombinator.com/item?id=45820807

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It all started when Stavros's blog was circulated on Hacker News! The way we approached the search part was by using "Spectral Bloom Filters" - https://theory.stanford.edu/~matias/papers/sbf-sigmod-03.pdf - which is based on a paper by Saar Cohen and Yossi Matias from the early 2000s - its basically an iteration on the counting bloom filters. We used the minimal selection and minimal increase algorithm from the paper for insertion and ranking of results.

I wrote a blog on it too - https://pncnmnp.github.io/blogs/spectral-bloom-filters.html

Some slides - https://pncnmnp.github.io/blogs/sthir-talk-2020.pdf

Comments URL: https://news.ycombinator.com/item?id=45782702

Points: 51

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Comments URL: https://news.ycombinator.com/item?id=45744151

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Comments URL: https://news.ycombinator.com/item?id=45614803

Points: 2

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A classic example of invariant I can think of is the min-heap - node N is less than or equal to the value of its children - the heap property.

Five years from now, you might forget the operations and the nuanced design principles, but the invariants might stay well in your memory.

> The Perseverance rover has explored and sampled igneous and sedimentary rocks within Jezero Crater to characterize early Martian geological processes and habitability and search for potential biosignatures ..... the organic-carbon-bearing mudstones in the Bright Angel formation contain submillimetre-scale nodules and millimetre-scale reaction fronts enriched in ferrous iron phosphate and sulfide minerals, likely vivianite and greigite, respectively.

> Organic matter was detected in the Bright Angel area mudstone targets Cheyava Falls, Walhalla Glades and Apollo Temple by the SHERLOC instrument ..... A striking feature observed in the Cheyava Falls target (and the corresponding Sapphire Canyon core sample), is distinct spots (informally referred to as ‘leopard spots’ by the Mars 2020 Science Team) that have circular to crenulated dark-toned rims and lighter-toned cores

> PIXL XRF analyses of reaction front rims reveal they are enriched in Fe, P and Zn relative to the mudstone they occur in ..... In the reaction front cores, a phase enriched in S-, Fe-, Ni- and Zn was detected

> Given the potential challenges to the null hypothesis, we consider here an alternative biological pathway for the formation of authigenic nodules and reaction fronts. On Earth, vivianite nodules are known to form in fresh water ..... and marine ..... settings as a by-product of low-temperature microbially mediated Fe-reduction reactions.

> In summary, our analysis leads us to conclude that the Bright Angel formation contains textures, chemical and mineral characteristics, and organic signatures that warrant consideration as ‘potential biosignatures’ that is, “a feature that is consistent with biological processes and that, when encountered, challenges the researcher to attribute it either to inanimate or to biological processes, compelling them to gather more data before reaching a conclusion as to the presence or absence of life .....

I had to look up PIXL XRF from this paper - https://arxiv.org/pdf/2402.01544 - it is:

> The Planetary Instrument for X-ray Lithochemistry (PIXL) is an X-ray fluorescence (XRF) spectrometer mounted on the arm of the National Aeronautics and Space Administration’s (NASA) Mars 2020 Perseverance rover (Allwood et al., 2020; Allwood et al., 2021). PIXL delivers a sub-millimeter focused, raster scannable X-ray beam, capable of determining the fine-scale distribution of elements in martian rock and regolith targets. PIXL was conceived following the work by Allwood et al. (2009) that demonstrated how micro-XRF elemental mapping could reveal the fine-textured chemistry of layered rock structures of ~3,450-million-year-old Archean stromatolitic fossils. Their work not only pushed back the accepted earliest possible window for the beginning of life on Earth, but also demonstrated that significant science return might be possible through XRF mapping. PIXL was proposed, selected, and developed to carry out petrologic exploration that provide the paleoenvironmental context required in the search for biosignatures on Mars, analogous to Allwood et al.’s earlier work.

Also, I wanted to mention something interesting - back when LLM-driven applications were just emerging, someone posted on Hacker News about how they categorized In Our Time episodes using the Dewey Decimal System with LLMs. Cool stuff - https://news.ycombinator.com/item?id=35073603

Comments URL: https://news.ycombinator.com/item?id=44998544

Points: 10

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I am still going through it, but the latter is quite interesting!

In it, he stated the following:

> Indeed, the famous “backpropagation” algorithm that was rediscovered by David Rumelhart in the early 1980s, and which is now viewed as being at the core of the so-called “AI revolution,” first arose in the field of control theory in the 1950s and 1960s. One of its early applications was to optimize the thrusts of the Apollo spaceships as they headed towards the moon.

I was wondering whether anyone could point me to the paper or piece of work he was referring to. There are many citations in Schmidhuber’s piece, and in my previous attempts I've gotten lost in papers.

Comments URL: https://news.ycombinator.com/item?id=44850716

Points: 3

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> On 11 February 1963, the Beatles recorded ten songs during a single studio session for their debut LP, Please Please Me.

> Martin asked the band if they had any songs that they could record quickly. According to Martin, "It was a straightforward performance of their stage repertoire – a broadcast, more or less." Initially, a morning and afternoon session only were booked; the evening session was added later. Mark Lewisohn later wrote: "There can scarcely have been 585 more productive minutes in the history of recorded music".

Interestingly,

> .... the Beatles arrived with John Lennon suffering from a bad cold, which he attempted to treat with a steady supply of throat lozenges

https://en.wikipedia.org/wiki/Please_Please_Me