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Cosmologically Unique IDs

jasonfantl.com

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Re: Cosmologically Unique IDs

#101

Post by kmoser »

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point.

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.

Re: Cosmologically Unique IDs

#102

Post by Zambyte »

buzzerbetrayed wrote: post #41
ekipan wrote: post #18

I forget the context but the other day I also learned about Snowflake IDs [1] that are apparently used by Twitter, Discord, Instagram, and Mastodon. 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…

Getting the entire universe to agree on a single clock for creating timestamps sounds absurdly difficult. Probably impossible?

You don't need the universe to agree. You need your ID system to agree within a reasonable margin of error.

Re: Cosmologically Unique IDs

#103

Post by NoMoreNicksLeft »

kmoser wrote: post #101

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point. This doesn't take into account that you will inevita…

>And don't even get me started on assigning unique IDs to each subatomic particle.

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.

Re: Cosmologically Unique IDs

#104

Post by nivertech »

kmoser wrote: post #101

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point. This doesn't take into account that you will inevita…

So UUIDv∞ will be at least 536 bit long?

And with group IDs, timestamp, etc. - 1024 bit long?

Re: Cosmologically Unique IDs

#105

Post by quijoteuniv »

lisper wrote: post #7

This analysis is not quite fair. It takes into account locality (i.e. the speed of light) when designing UUID schemes but not when computing the odds of a collision. Collisions only matter if the colliding UUIDs actually come into causal contact with each other after being generated. So just as you have to take locality into account when designing UUID trees, you also have to take it into account when computing the o…

The answer is 42. Have it from good source!

Re: Cosmologically Unique IDs

#106

Post by Dylan16807 »

kmoser wrote: post #101

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point. This doesn't take into account that you will inevita…

> 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.).

Sure it does. Those are not going to add up to a single extra bit.

Re: Cosmologically Unique IDs

#108

Post by kmoser »

Dylan16807 wrote: post #106
kmoser wrote: post #101

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point. This doesn't take into account that you will inevita…

> 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.). Sure it does. Those are not going to add up to a single extra bit.

Even every possible permutation of every single subatomic element in the universe? Even if we just consider atoms, at 10^80 atoms in the entire universe, there are (10^80)! possible permutations, which is many, many, many orders of magnitude larger.

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.

Re: Cosmologically Unique IDs

#109

Post by zdragnar »

kmoser wrote: post #108
Dylan16807 wrote: post #106

Earlier quoted context omitted.

> 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.). Sure it does. Those are not going to add up to a single extra bit.

Even every possible permutation of every single subatomic element in the universe? Even if we just consider atoms, at 10^80 atoms in the entire universe, there are (10^80)! possible permutations, which is many, many, many orders of magnitude larger. 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.

New atoms form all the time, either through fusion or fission. The latter is happening right now all around you- either from potassium in plants breaking down, to radon gas that sept up from the ground, to carbon itself. All of these have unstable isotopes with half lives short enough to have at least a little activity near you.

Given that constant change to the available combinations of sets, it would seem that a truly capable system would need to be practically infinite, no?

Re: Cosmologically Unique IDs

#110

Post by liamwire »

NoMoreNicksLeft wrote: post #103
kmoser wrote: post #101

> A more reasonable upper limit might be to assume that every atom in the observable universe will get one ID (we assume atoms won’t be assigned multiple IDs throughout time, which is a concession). There are an estimated atoms in the universe. Using the same equation as above, we find that we need 532 bits to avoid (probabilistically) a collision up to that point. This doesn't take into account that you will inevita…

>And don't even get me started on assigning unique IDs to each subatomic particle. 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.

For the uninitiated: https://en.wikipedia.org/wiki/One-electron_universe
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