(Gotta say here that I love HN. It's one of the very few places where a comment that geeky and pedantic can nonetheless be on point. :-)
It was an interesting couple of days before we figured it out.
As the universe expands the gap between galaxies widens until they start "disappearing" as no information can travel anymore between them. Therefore, if we assume that intelligent lifeforms exist out there, it is likely that these will slowly converge to the place in the universe with the highest mass density for survival. IIRC we even know approximately where this is.
This means a sort of "grand meeting of alien advanced cultures" before the heat death. Which in turn also means that previously uncollided UUIDs may start to collide.
Those damned Vogons thrashing all our stats with their gazillion documents. Why do they have a UUID for each xml tag??
We do see light from galaxies that are receding away from us faster than c. At first the photons going in our direction are moving away from us but as the universe expands over time at some point they find themselves in a region of space that is no longer receding faster than c, and they start approaching.
A galaxy has enough resources to be self-reliant, there’s no need for a species to escape one that is getting too far away from another one.
From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.
Conservation of mass and energy is an empirical observation, there is no theoretical basis for it. We just don't know any process we can implement that violates it, but that doesn't mean it doesn't exist.
Pedantry ftw.
This doesn't take into account that you will inevitably want to assign unique IDs to various groups of atoms (e.g. this microchip, that car, etc.). And don't even get me started on assigning unique IDs to each subatomic particle.
You only need one ID for each type of particle. Since the laws of physics dictate that the particles themselves are indistinguishable from each other.
In other words, the act of 'assignment' presupposes some mechanism of assignment, and at a certain level of granularity the information needed for that mechanism to function is greater than the information the system can store.
It would be like assigning each byte in a stick of ram a 32 bit random access ID, and trying to store the assignments in the same memory space. Memory addressing only works because we assume a linear, unchanging order.
Sure it does. Those are not going to add up to a single extra bit.
And this isn't even counting sets that include multiples of the same item; once you get into that territory, there really is no upper bound.
If a neutrino oscillates between flavors, does it get 3 IDs? Or does it get a new ID with each oscillation?
Thankfully, we only need one electron ID at all.
And with group IDs, timestamp, etc. - 1024 bit long?
Timestamp + random seems like it could be a good tradeoff to reduce the ID sizes and still get reasonable characteristics, I'm surprised the article didn't explore there (but then again "timestamps" are a lot more nebulous at universal scale I suppose). Just spitballing here but I wonder if it would be worthwhile to reclaim ten bits of the Snowflake timestamp and use the low 32 bits for a random number. Four billion IDs for each second.
There's a Tom Scott video [2] that describes Youtube video IDs as 11-digit base-64 random numbers, but I don't see any official documentation about that. At the end he says how many IDs are available but I don't think he considers collisions via the birthday paradox.
Apparently with the birthday paradox 32 bit random IDs only allow some tens of thousands per second before collision chance passes 50%. Maybe that's acceptable?
Isn't this just the same scheme as version 1 UUID, except with half the bits? I guess they didn't want to dedicate 128 bits to their IDs.
Received Message
Encryption: 0
From: GC Transit Authority --- Gora System (path: 487-45411-479-4)
To: Ooli Oht Ouloo (path: 5787-598-66)
Subject: URGENT UPDATE
Looks like this multispecies universe has centrally-agreed-upon path addressing system.
My argument was the 2^256 actually approaches the number of atom in the observable universe (within 1 to 3 orders of magnitude), and that collisions are so unlikely that we'll have millions of datacenter meltdowns first (all assuming we have a good source of random numbers, of course). In the end I convinced everybody that even 128 bits are good enough, without any collision checking required.
I thought my arguments was clever, but this is so much better. :)
The total amount of computer data across all of humanity is less that 1 yottabyte. We're expected to reach 1 yottabyte within the next decade, and will probably do so before 2030. That's all data, everywhere, including nation-states.
The birthday paradox says that you'll reach a 50% chance of at least one collision (as a conservative first order approximation) at the square root of the domain size. sqrt(2^256) is 2^128.
Now, a 256 bit identifier takes up 32 bytes of storage. 2^128 * 32 bytes = 10^16 yottabytes. That's 10 quadrillion yottabytes just to store the keys. And it's even odds whether you'll have a collision or not.
And if the 50% number scares them, well, you'll have a 1% chance of a collision at around... 2^128 * 0.1. Yeah, so you don't reach a 1% over the whole life of the system until you get to a quadrillion yottabytes.
Because you're never getting anywhere near the square root of the size, the chances of any collision occurring are flatly astronomical.
If it's not distributed you can just have a counter
If it's distributed but coordinated by a single party (say, it's your servers), you can do sharding on incremented counters. Like, every server are assigned a region of ids
10-20 bits: version/epoch
10-20 bits: cosmic region
40 bits: galaxy ID
40 bits: stellar/planetary address
64 bits: local timestamp
This avoids the potentially pathological long chain of provenance, and also encodes coordinates into it.
Every billion years or so it probably makes sense to re-partion.
00 04: Version + Flags
04 08: Timestamp (uint64)
12 16: Node/Agent Hash
28 16: Namespace Hash
44 32: Random Entropy
76 20: Extra / Extension
96 32: Integrity Hash
One upside of the deterministic schemes is they include provenance/lineage. Can literally "trace up" the path the history back to the original ID giver.
Kinda has me curious about how much information is required to represent any arbitrary provenance tree/graph on a network of N-nodes/objects (entirely via the self-described ID)?
(thinking in the comment: I guess if worst case linear chain, and you assume that the information of the full provenance should be accessible by the id, that scales as O(N x id_size), so its quite bad. But, assuming "best case" (that any node is expected to be log(N) steps from root, depth of log(N)) feels like global_id_size = log(N) x local_id_size is roughly the optimal limit? so effectively the size of the global_id grows as log(N)^2? Would that mean: from the 399 bit number, with lineage, would be a lower limit for a global_id_size be like (400 bit)^2 ~= 20 kB (because of carrying the ordered-local-id provenance information, and not relative to local shared knowledge)
Provenance is a DAG, so you get a partial order for free by topological sort. That can be extended to a compatible total order. Then provenance for a node is just its ordering. This kind of mapping from objects to the first N consecutive naturals is also a minimal perfect hash function, which have n log n overhead. We can't navigate the tree to track ancestry, but equality implies identical ancestry.
Alternatively, we could track the whole history in somewhat more bits with a succinct encoding, 2N if it's a binary tree.
In practice, deterministic IDs usually accept a 2^-N collision risk to get log n.
Each “post” has a CID, which is a cryptographic hash of the data. To “prove” ownership of the post, there’s a witness hash that is sent that can be proved all the way up the tree to the repo root hash, which is signed with the root key.
Neat way of having data say “here’s the data, and if you care to verify it, here’s an MST”.
And best feature: anyone can generate a random id of such representation by getting a deck of cards and shuffling it properly. Playing cards are ubiquitous. I can see a camera "reading" the decks after they've been splayed on a table after a shuffle. This might even make a better random number seeds.
You're not sure if there is any demand for this sort of stuff? Look at dicekeys:
I think you glossed over the big weakness in the idea.
CSPRNGs make prediction of the next number difficult (cracking-AES difficulty) but do not add entropy and must be seeded uniquely otherwise they will output the same numbers. Unless the author is proposing having the same machine generate a single universe-scale list in one run.
Also “banning” ids that are all 1s or 0s is silly; they are just as valid and unique as any other number if you’re generating them properly. Although I might suggest purchasing a lottery ticket if you get an UUID with all settable bits as 1.
Imagine if example.com was freely available for anyone to register, think of all the email they could get.
If you have an infinite multiverse of infinite universes, and perhaps layers on that, with different physics, etc., you can’t have identity outside of all existence.
In Judaism, one/the name of God is translated as “I am”. I believe this is because God’s existence is all, transcending whatever concepts you have of existence or of IDs. That ID is the only ID.
So, the cosmic solution to IDs is the name of God.
I build a whole database around the idea of using the smallest plausible random identifiers, because that seems to be the only "golden disk" we have for universal communication, except for maybe some convergence property of latent spaces with large enough embodied foundation models.
It's weird that they are really under appreciated in the scientific data management and library science community, and many issues that require large organisations at the moment could just have been better identifiers.
To me the ship of Theseus question is about extrinsic (random / named) identifiers vs. intrinsic (hash / embedding) identifiers.
https://triblespace.github.io/triblespace-rs/deep-dive/ident...
https://triblespace.github.io/triblespace-rs/deep-dive/tribl...
Also, network routing requires objects that have multiple addresses.
Physics side of whole thing is funny too, afaik quantum particles require fungibility, i.e. by doxxing atoms you unavoidably change the behavior of the system.
There's nothing stopping a entity from requesting multiple IDs from one of the "devices"!
Minor correction: Satellites don't go in every direction; they orbit. Probes or spaceships are more appropriate terms.
- Infinity : from school, we learn our universe is infinite.
- We often do calculation with upper limit like this one : 10^240. This is a big number butttttt it's not infinite you know. 10^240+1, 10^240+2...
So :
1. if it's infinite, why doing upper limit calculation ?
2. if it's limited, what is there outside that limit ?
Extremly paradoxal
But practically it's finite because we are only in causal contact with things up to 13.7b ly from us, and given space appears to be expanding at an accelerating rate, we probably will never get into causal contact with (almost all of) the part of the infinite universe outside of our light cone, even though things ought to exist over the "horizon". So only a tiny infinitesimal sliver of the infinite universe is knowable by us.
If it takes at least Npb particles to store one bit of information, then the number of addressable things would decrease with the number of bits of the address.
So let's call Nthg the number of addressable things, and assume the average number of bits per address grows with Nb = f(Ntng).
Then the maximum number of addressable things is the number that satisfies Nthg = Np/(Npb*f(Ntng)), where Np is the total number of particles.
I guess I'm wondering if there is a way to construct a universal coordinate frame for the whole universe? If so, then its possible to trivially assign local time + x + y + z + salt to make unique ids.
On the contrary, having the right to assign IDs is powerful; on balance, to my mind the right thing to do is some sort of a ZK verifiable random function, e.g. sunspot-based transformations combined with some proof of ‘fair’ random choice. In that case, I think the 800 bit number seems like plenty. You could also do some sort of epoch-based variable length, where for the next billion years or so, we use 1/256 of the ID space, (forced first bit to 0), and so on.
Tumblers are modeled using transfinite numbers which makes me wonder: what are the similarities and differences between transfinite numbers and Elias omega encoding? I'm not well versed in either, so I expect it's either a question from ignorance or I may have a lot to learn. :)
1. https://www.artandpopularculture.com/Tumbler_%28Project_Xana...
I could split this object into 10^500 or 10^50^500^5000 etc., with imagination being the limit.
These values Id'd at whatever imaginable resolution are far from practically useful but at a cosmic scale, there is no telling what is a useful value?
So this framework seems to be more limiting because we define a resolution ?
That way you can route ships or data or whatever to a specific system in a logical way. Each system decides how to allocate addresses. Since most systems won’t have anything or anyone to care, something like NASA or registrars would just allocate a block to the system and give large things like planets an address.
I’m also going to devise a standard that arbitrarily breaks it into groups of hexadecimal digits of arbitrary length in the spirit of UUIDs, and reserve a prefix space for Planck-unit timestamps (computronium-ID-7) so that you can lexicographically sort your COMPID7s.
Man I got to get out in front of this.