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Cosmologically Unique IDs

jasonfantl.com

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Re: Cosmologically Unique IDs

#111

Post by cuttothechase »

One could take anything like a cell and split it into genes, molecules, atoms, sub-atomic wave functions (with infinite value range) and take time which can be split into another infinite entity say even within a finite interval. How does this analysis account for that?

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 ?

Re: Cosmologically Unique IDs

#112

Post by giraldorich »

itishappy wrote: post #93
frikit wrote: post #32

Earlier quoted context omitted.

Protons can decay because the distinction between matter and energy isn't permanent. Two quarks inside the proton interact via a massive messenger particle. This exchange flips their identity, turning the proton into a positron and a neutral pion. The pion then immediately converts into gamma rays. Proton decayed!

This destroys a baryon, an operation which is prohibited by the standard model.

Baryon number is an accidental symmetry, not a fundamental one. Unlike charge or color, it is not protected by a gauge principle and is just a consequence of the field content and renormalizability at low energies.

The standard model is almost certainly an effective field theory and a low-energy approximation of a more comprehensive framework. In any ultraviolet completion, such as a GUT, quarks and leptons inhabit the same multiplets. At these scales, the distinction between matter types blurs, and the heavy gauge bosons provide the exact mediation mechanism described to bypass the baryon barrier.

Furthermore, the existence of the universe is an empirical mandate for baryon-violation. If baryon number were a strict, immutable law, the Sakharov conditions could not be met, and the primordial matter-antimatter symmetry would have resulted in a total annihilation. Our existence is proof that baryon number is not conserved. Even within the current framework, non-perturbative effects like sphalerons demonstrate that the Standard Model vacuum itself does not strictly forbid the destruction of baryons.

Re: Cosmologically Unique IDs

#113

Post by adrianN »

dheera wrote: post #52
u1hcw9nx wrote: post #15

Earlier quoted context omitted.

You must consider both time and locality. From now until protons decay and matter does not exist anymore is only 10^56 nanoseconds.

Protons (and mass and energy) could also potentially be created. If this happens, the heat death could be avoided. 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.

All of physics is „just“ based on empirical observation. It’s still a pretty good tool for prediction.

Re: Cosmologically Unique IDs

#114

Post by Towaway69 »

disconcision wrote: post #83
hnuser123456 wrote: post #28

Earlier quoted context omitted.

And recent DESI data suggests that dark energy is not constant and the universe will experience a big crunch in a little more than double its current age, for a total lifespan of 33 billion years, no need to get wild with the orders of magnitude on years into the future. The infinite expansion to heat death over 10^100 years is looking less likely, 10^11 years should be plenty. https://www.sciencedaily.com/releases/2…

not obvious to me this makes things better as opposed to worse? sure, the time bound helps but in the runup to a crunch won't we get vastly more devices in causal range at an asymptotically increasing rate?

Who’s there doing the counting? I would assume the temperatures at those extremes won’t support life in its known forms.

Perhaps some Adamesque (as in douglas adams) creature whose sole purpose is to collect all unique UUIDs and give them names.

Re: Cosmologically Unique IDs

#115

Post by wavemode »

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…

> 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.

Re: Cosmologically Unique IDs

#116

Post by jl6 »

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…

Ah but if we are considering near-infinitesimal probabilities, we should metagame and consider the very low probability that our understanding of cosmology is flawed and light cones aren’t actually a limiting factor on causal contact.

Re: Cosmologically Unique IDs

#117

Post by moktonar »

The random uuid selection is far superior because of lifespan, you can only have so many functioning devices at the same time, and on the contrary to tree-based uuids once a device is decommissioned the uuid can be reclaimed. Practically though it would probably be a mixed algorithm where positioning would give the id root and the rest is selected randomly

Re: Cosmologically Unique IDs

#118

Post by Drakim »

wavemode wrote: post #115
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…

> 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.

Don't they have different x,y,z positions?

Re: Cosmologically Unique IDs

#119

Post by nextaccountic »

linuxhansl wrote: post #92

Heh. I once had to make an argument that 256 bit randomly assigned identifiers are good enough without explicit collision checking. People wanted me to add complex and expensive collision checks. 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…

If the mechanism for generating those 256 random bits is distributed and untrusted parties generate ids, then you need collision detection because they may be malicious

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

Re: Cosmologically Unique IDs

#120

Post by ForHackernews »

Drakim wrote: post #118
wavemode wrote: post #115

Earlier quoted context omitted.

> 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.

Don't they have different x,y,z positions?

That's unclear https://en.wikipedia.org/wiki/One-electron_universe
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