u/Tessellator-1

※ this sentence was translated from Japanese to English by Chat GPT. Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated.

If proton decay occurs, the predicted half-life of the proton is somewhere between 10^34 and 10^36 years. This made me wonder: what will actually happen to the things that exist in the universe between now and that unimaginably distant era?
I often see timelines describing the future evolution of stars, but I’d like to know what will happen, scientifically, to the following six things by around 10^36 years from now.

1: 1 kg iron sphere
(I’ve heard that iron is one of the most stable elements.)
2: stone monument
(Would inscriptions remain readable for an extremely long time, or would the writing eventually disappear?)
3: can of food
(What would happen to food sealed inside a can over such an enormous span of time?)
4: manufactured industrial product
(Any particular example of an interesting industrial product would be fine.)
5: planet
(What would happen to a planet if it somehow avoided being swallowed by its star?)
6: intelligent civilization
(Could an intelligent civilization that made extensive use of reversible computing potentially survive for an extremely long time in a simulated or virtual environment?)

For #1–4, please assume that the objects are floating in a vacuum. If they would eventually be destroyed or worn away by interactions with the interstellar medium, I’d also be interested to know what would happen if we ignore the interstellar medium.
I’d also love to hear about anything else you think would be particularly noteworthy or interesting. Thank you!

First of all, I would like to say that I have no knowledge about computer science.

I recently heard about something called reversible computing. As I understand it, in ordinary computers, erasing information about the intermediate steps of a computation causes energy to be released as heat. But in reversible computing, the information from all the intermediate steps is preserved, so apparently, if we could build a computer capable of doing this, it could theoretically perform computations with essentially no energy consumption.
This made me wonder about something, and I’d love to hear from anyone knowledgeable about physics or computational theory:
If you never erase the information generated during a computation, wouldn’t the amount of storage required keep increasing as the computer performs more and more calculations?
I previously came across a science-related page online that said that an intelligent civilization that has mastered reversible computing wouldn’t need “Dyson’s eternal intelligence” to survive the heat death of the universe.
But wouldn’t such a civilization still need an absolutely enormous amount of storage to preserve all the information generated during its computations?
Or is there some way to preserve the information from the computational process without actually requiring additional physical storage?
I’m especially curious about how this works in the context of extremely long-term civilizations trying to survive the heat death of the universe.

By the way, this sentence was translated from Japanese to English by Chat GPT. Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

I'm thinking of featuring a 1980-born person named Deepansh in a story set in India, but isn't it unnatural to call him Dee instead of Deep?

By the way, I can't change the name Deepansh anymore, but I've heard that this name is a relatively recent name, so please tell me how unnatural it is to have this name.

Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

What should I do to make the civilian clothes, bags, and belt pouches that I use on a daily basis look like the old, dirty clothes worn by the characters in the popcorn movie?
Can I do the same used processing as the actual movie costumes at home?
Clothes are washed frequently, but bags and belt pouches are rarely washed.
By the way, we are considering making our own belt pouch using paraffin canvas or biowash canvas.

Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

Please note that this post was translated from Japanese to English using AI. Because of this, some details or nuances may have unintentionally shifted from my original meaning. Thank you for your understanding.

I once heard that humans can stay healthy without consuming organisms that possess a central nervous system. As far as I’ve researched, that seems to be true. Yet, I still eat meat—either as a culinary indulgence to please my palate, or simply to make meal management easier.
This recently made me wonder: is what I’m doing committing an ethical taboo similar to stomping a stray dog to death just for entertainment or stress relief? If harming a stray dog is wrong, I feel like my actions can only be justified by a matter of degree—like the difference between stealing $1 versus stealing $100.
Just like slave owners in the past, will I eventually be looked down upon by future generations as a coward who simply grew complacent in their social environment?

If you happen to be someone who thinks eating meat is acceptable but direct violence against animals is not—or vice versa—I would love to hear your reasons in the comments. Your perspective would be incredibly valuable as I continue to think through this.

Please note that this post was translated from Japanese to English using AI. Because of this, some details or nuances may have unintentionally shifted from my original meaning. Thank you for your understanding.

I once heard that humans can stay healthy without consuming organisms that possess a central nervous system. As far as I’ve researched, that seems to be true. Yet, I still eat meat—either as a culinary indulgence to please my palate, or simply to make meal management easier.
This recently made me wonder: is what I’m doing committing an ethical taboo similar to stomping a stray dog to death just for entertainment or stress relief? If harming a stray dog is wrong, I feel like my actions can only be justified by a matter of degree—like the difference between stealing $1 versus stealing $100.
Just like slave owners in the past, will I eventually be looked down upon by future generations as a coward who simply grew complacent in their social environment?

If you happen to be someone who thinks eating meat is acceptable but direct violence against animals is not—or vice versa—I would love to hear your reasons in the comments. Your perspective would be incredibly valuable as I continue to think through this.

Amazon prime video?
Netflix?
rent a disc?
buy a disc?
television broadcast?
Illegal uploading on the Internet?

By the way, the answer is fine in English, but since I'm Japanese, it would be helpful if you could write so that mistranslation is as unlikely as possible.

Before posting various things, I would like to know when to post to get more replies on "HardSciFi".
It would be helpful if you could write the time zone and country properly instead of "just now" or "about 2 hours later".
If it's important, I'd be happy if you could tell me about the day of the week.

Also, I want to ask for the future, but when the content of the post is a “question”, which of the four Flair should I choose? I don’t know because I’m using it translated into Japanese, so I’m choosing “Discussion” for recent.
However, I chose "Meta" in this post.

A question for those knowledgeable in science!

I recently heard about Dyson's Eternal Intelligence in a Kurzgesagt video on YouTube. That got me wondering—if your thoughts slow down in exchange for extending the duration of your thinking, isn't it meaningless?
Could you please explain the mechanism and purpose of Dyson's Eternal Intelligence in an easy-to-understand way?
By the way, this sentence was translated from Japanese to English by Chat GPT. Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

"Quick question for the science community: how long can intelligent life actually survive in our universe? I saw a thread on another subreddit about proton decay, and the general consensus was that humanity won't even make it to \(10^{34}\) years. So, what is the ultimate expiration date for intelligence in the universe, and what exactly sets that limit? I imagine the stability of elements plays a huge role here, but could you explain it in relatively simple terms?"

By the way, this sentence was translated from Japanese to English by Chat GPT. Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!”

Question for people who know a lot about cosmology!

I read that the Japanese Kamiokande experiments have been searching for proton decay, and that current results suggest that the proton’s half-life is at least about 10^34 years. That made me wonder about two things.

First, if proton decay is real, is it possible that human civilization could still exist when protons begin to decay in large numbers? In other words, could humanity survive until the earliest time when proton decay might become important? Or is it more likely that civilization would disappear long before then because it would eventually use up all available energy gradients needed to sustain activity?

Second, if human civilization somehow did survive into the era when proton decay becomes significant, what kinds of problems would it face? Would matter gradually become less available, making it harder and harder to build computers, power generators, and other technology needed for civilization and thought? If the Local Group becomes isolated because of cosmic expansion, and then the amount of matter in it slowly decreases because of proton decay, would civilization inevitably fade away along with the remaining matter?

As a small clarification: if the word "civilization" is too broad or abstract for this question, you can interpret it as "intelligence" instead.

By the way, this sentence was translated from Japanese to English by Chat GPT.
Feel free to answer in English. However, I only understand Japanese, so I would really appreciate clear and simple English that is less likely to be mistranslated. Thank you!

**　**postscript:
Thanks for all the replies, everyone! I got a lot of comments explaining what half-life is.
Maybe I didn't word it well, but I do get that things decay gradually until they hit the halfway mark, and that it takes an insane amount of time.

What I’m actually wondering is this: once protons keep decaying and we hit that 1/2, 1/16, or 1/64 mark—if we somehow manage to stay intelligent—physical hardware will inevitably run out over those eons. In that kind of world, could we actually transition to an environment where intelligence doesn't rely on protons at all?
Also, a few of you mentioned that intelligence wouldn't even survive that long. If you don't mind, could you tell me about the more immediate, concrete limits we’d hit way before that?

I have a question for someone who is familiar with the universe.
I'm looking for a list of the distance between each super clusters and the Earth. Let me know if there's anything good!

宇宙に詳しい人に質問！
SFの創作に登場させるエイリアンを、地球から数十億光年くらい離れたところにある銀河にいる設定にしたいんだけれど、名前の付いた実在する銀河にしても大丈夫なの？
観測可能な範囲にある銀河は2兆個あるらしいけど、それって計算上の予測であって、全てを実際に発見したわけじゃないでしょ？つまり、名前の付いた銀河は2兆個のうちの一部であって、それを創作に使うと不自然？

もちろん物語の内容次第なのは分かってるけど、少なくとも、ワケがあって人類に選ばれた銀河っていう設定じゃないよ。だけど人類と関わるから、全く別の宇宙って設定にするわけにもいかないんだ。
もし観測可能な範囲のほとんどの銀河に何かしらの番号があるなら、そのどれかを設定に使うけど、そうじゃないなら、やっぱり架空の銀河を考えるべきかな？実在するclusterかgroupに属する架空の銀河って設定にするのもありかな？

あと、銀河や銀河群の地球からの距離が分かるような一覧があれば教えて！

Translation apps are not good, so please use your Reddit translation.

軍事に詳しい人に質問。
核ミサイルが発射されたら迎撃できるけど、
もしもこっそり持ち込まれてたら？
例えば、ターゲットの国の海岸で、潜水艦からトレーラーのコンテナに核爆弾をこっそり移すとか。
もちろん、コンテナにはありふれた民間企業のロゴが入ってる。こうなったらもう対処できない上に誰がやったかも分からないよね？

宇宙や科学に詳しい人に質問！
物体や情報は光速を超えられないから、宇宙が膨張しているなら、遠くにある銀河群に行ったり信号を送ったりできるタイムリミットがあるよね。それにもし戻ってくることも想定するならタイムリミットは更に短いよね。
それじゃあ例えば、人類が出した電磁波をキャッチした異星人が僕らに返信するとしたら、どのくらい離れた位置にいる異星人までならそれが可能？
宇宙が膨張する速度は時代によって違うらしいから、人類が電磁波を発したのは現代っていうことを前提に教えて。