r/paradoxes

▲ 570 r/paradoxes+4 crossposts

Why Is the Night Sky Dark?

Why is the night sky dark? 🌌

Erika Hamden breaks down Olbers' Paradox, the cosmic puzzle that helped scientists first hypothesize that the universe had a beginning. In an infinite, infinitely old universe, every point in the night sky should eventually have a star behind it, making the night sky just as bright as daytime. The fact that darkness exists tells us that not enough time has passed for all that light to reach us, or that stars simply have not formed yet in those regions of space.

This project is part of IF/THEN®, an initiative of Lyda Hill Philanthropies.

u/TheMuseumOfScience — 2 days ago

This post is false

This post is false, therefore it is true about being false. But if it is true, it is false about being false. But if it is false, then it is true about being false. But if it is true, it is false about being false. But if it is false, then it is true about being false. But if it is true, it is false about being false. But if it is false, then it is true about being false. But if it is true, it is false about being false. But if it is false, then it is true about being false.

A bland paradox but might as well.

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u/Mission_Promotion937 — 2 days ago

Sandwiches' paradox

Sandwiches, as in, prepared for you, at lunch time, during office hours, are generally tolerated, if not, recommended. Convenient, supporting a local business and affordable (because of city centre pay scales), they do seem like a no brainer. If large scale or small scale economics experience a turndown, however, sandwiches are, apparently, to blame for all ill managed personal finances?

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u/helmeton — 2 days ago

Wish for wealth paradox

"I wish I am always wealthier than the wealthiest person in the world."

This is a logical paradox.

Let S be the set of all the people in th world, and let W be the wealth of the richest person in the world. Mathematically, W is defined as the maximum value in that set:

>W = max[p ∈ S] (wealth(p))

My wish establishes a strict condition for my own wealth (U):

>U > W

because i exist in the world, I'm a member of thta set (me ∈ S). The moment the wish is granted, my welath is U becomes greater than everyone else's wealth. By definition, I'm now the richest person, meaning the maximum wealth in the world is now mine:

>W = U

If we substitute this back into my original wish condition (U > W), we get:

>U > U

This is a logical contradiction. In propositional logic and standard arithmetic, strict inequality is irreflexive, a value cannot be strictly greater than itself.

If we assume the doesn't just throw a error and collapse for some reason, but instead tries to process my wish like an iterative feedback loop (a program running on sequential "ticks"), here is how it plays out:

(This is a example)

Tick 0: The richest man has $800 billion i think. My wish get granted. I'm now granted $800 billion + $1.

Tick 1: The system reevaluates. Who is the richest man now? Me, with $800 billion + $1. The wish dictates i must be richer than the richest man. The system adds another dollar. My wealth is now $800 billion + $2.

Tick 2: I'm still the richest man. The system adds another dollar. If this evaluation happens continuously with zero time delay (Δt → 0), my welath doesn't stop at a finite number, it would scales to infinity instantly instead ig.

edit: Since no one gets it. I had to explain. i can never possess more wealth than myself, making the condition mathematically and logically impossible to satisfy.

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u/Technical-Security99 — 5 days ago

Pinocchio paradox "solution" (maybe and its not that interesting)

A lie is only a lie if you believe what you're saying is false. If Pinocchio says "my nose will grow now" and he believes his nose will grow, it will not grow. If he is unsure, his nose will do the opposite of what he's leaning towards believing it will do, as its basically impossible to be completely unsure. There's probably a flaw in this somewhere, so correct me if there is.

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u/Elegant_Committee854 — 4 days ago

This is actually a paradox

Imagine an super duper advanced civilization builds the "Perfect AM," an AI designed to store every truth and predict every future event in the universe. It works flawlessly, and its database contains the ultimate, complete truth of reality. Now, consider the following scenerio.

AM's developers want to ensire their creation is perfectly accurate, so they instruct the AM to document its own existemce. AM generates a complete, flawless data file that perfectly describes evert single fact about itself, down to the exact position of its own subatomic particles.

Because the AM is part of the universe, this data file must inherently contain the data file itself (the description of the file must be stored within the file)

Therefore, the data file must infinitely contain itself. (let's assume the universe is infinitely big and long)

(I will reveal why it is the paradox tomorrow and will tag every single one of you. If someone already figured it out, i'll tag you all still but i'll not reveal the answer)

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u/Technical-Security99 — 4 days ago

Wish-lock Paradox

Imagine if one person wished that all of your wishes couldn't be granted, but then you make a wish that makes that persons wish seize to exist. Technically if that persons wish is true, your wish can't happen. But if you're wish is true, that persons wish stops being true.

reddit.com
u/Solid-Waltz-3956 — 7 days ago

Temporal replacement arrival paradox

I've linked my first attempt. This is a newer version...

A ship undergoes gradual replacement of its parts each month while observers and observer records are periodically replaced. The ship is defined as “the same ship” only when an observer concludes it is “new,” and defined as “new” only when an observer concludes it is “the same.” The ship is guaranteed to arrive at its destination only while classified as “new.” However, any observer identifying the ship as “new” thereby reclassifies it as “the same,” preventing the condition required for arrival, while identifying it as “the same” reclassifies it as “new” without establishing the condition necessary for arrival.

Question:

Does it arrive?

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u/Ayk0rn — 9 days ago

Temporal Replacement Paradox

I’ve been thinking about a paradox structure, combining some major ideas, and wanted to share it to see how it will be interpreted.

The idea is this:

A ship moves continuously through space while undergoing gradual replacement of its parts every month. At the same time, the observer tracking the ship has their memory reset every month and is fully replaced every year, meaning no continuous observational identity persists.

Despite this, the ship maintains uninterrupted motion and is guaranteed to arrive at a destination within a fixed 100-year interval. However, the exact arrival time cannot be logically predicted, because every observer capable of tracking or reasoning about it is itself subject to replacement and memory disruption.

This creates a tension between:

physical continuity vs material replacement

motion vs fragmented observation

guaranteed events vs unprovable prediction

The question:

If both the object and all observers of it are continuously replaced, does identity belong to the ship itself, the observers, or the continuity between them?

reddit.com
u/Ayk0rn — 9 days ago

PARADOX

(But not as a category.

As a collapsed label that stops meaning anything beyond itself.)

An entity that simultaneously contains all possible values, sizes, states, and descriptions, including mutually contradictory ones, such that any attempt to define, measure, or resolve it results in self-reference, infinite recursion, and irreconcilable contradiction; it exists and does not exist across all frames of reference, remains unchanged by any operation, and cannot be consistently contained within any logical or mathematical system, yet can be pointed to as the limit where description, size, and meaning collapse into one another.

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u/ScaryInternal3632 — 13 days ago

If there is other dimensions in the world There would be a infinite amount of universes since there would be a universe where you would first begin reading this post 9 days later or 4 hours later Infinite universes

But wouldnt that mean theres a universe where all the other universes are gone and thats the only universe left but still there would be a universe where there are other universes so how would that work?

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u/AnyZookeepergame8127 — 14 days ago