So I have a character that is always fast, a Speedster really, 1 second is 24 hours to her. As pointed out by multiple commenters, the character is moving so fast that she's essentially a ghost, and that she's be unable to have a civilian life. This lead to a different question. With everything moving so slow, she's essentially living a world of populated by statues. With a negligible ability to communicate with people, how would she try to communicate with people?
I'm thinking in the equivalent of the simultaneous exhibitions in chess/go, or if you want of a massively parallel penpal experience: she writes notes to (and reads answers from) many people at once. By doing this, she is able to hold a few tens of thousands of individual conversations at any given time.
This would give her the potential to be an extraordinary facilitator in consensus-based decision making, being able to gather in "real time" (for everyone else) opinions, ideas, facts and feelings, digest them and pass them on for a ginormous crowd. Or, depending on her ethical/social views, she could manipulate a society in crazy ways.
I'm assuming the statement in the previous question "I'm handwaving majority of physics and biology in relationship to the actual movement, and focusing on a more psychological angle." is still valid here. Still, let me briefly address worries about paper catching fire or being destroyed by friction. About combustion: it's not that hard to create a (locally) oxygen-depleted atmosphere if need be (e.g. burning a candle or matches to saturate the bottom of a bowl with CO2). About friction: graphite is industrially used as a dry lubricant, so I think it is credible that ultra-high-speed writing with pencils made of pure graphite (as in the old days) on appropriate surfaces will be non-destructive.
She writes a book.
She is, for all purposes, too fast to talk in any way. The shortest written messages take a few seconds to even make sense to us, and that's days to her.
So she writes a book, and emails someone whom she trusts can print it. If people take as little as a whole day to read it, to her it will look like two hundred and thirty-six years have elapsed. She will die of old age within a few of our hours anyway, which is too short a time to bond with anyone... Might as well think hard about some of humanity's biggest problems (are we grandchildren of mother nature's mother? Did dinosaur have penises? Why does Michael J. Fox have no Elvis in him?) and pen them down.
But she will do it in braille because, as explained in my answer in the previous, linked question, she can't see anything.
Ok so if your speedster tried to write, the pen/pencil will burn through the page with friction and emailing will be too slow with many broken keyboards.
Your speedster needs to figure out simple direct messages she wants to send to humanity. Best way to make sure she is heard is to carve her message into the ground.
Get a running start, then have your speedster stop by digging her feet into the ground. Write a message all of earth can see. Imagine like a crop circle message but inscribed into the earth.
She could change the message daily. Instruct people on how to live. Some people might even think it is a message from god.
Larry niven came up with an interesting idea for dealing with aliens that live at different timeframe references. They communicate via E-mail and digital media, you can read and answer at your own speed. Your speedster might need to build a custom rig (shes got the time)and type slowly but it should be possible. Electronics can be built for extremely high speed interface.
Like waiting for a letter from a sailor at sea in the old days.
But an alternative may be possible ...
Your speedster can employ any means to communicate which is written - i.e. does not depend on the ability to communicate using any frequency based system like talking.
Let's pick email.
Now I take between a few minutes and a day to reply to most emails depending on what they say and urgency.
Your speedster replies, from the point of view of ordinary time, in the blink of an eye, so that's no problem.
But you speedster must wait a very long time for replies to her emails.
Every minute it takes to reply in the real world equates to 60 days (two months !) in the Speedster's world.
So your speedster sends an email and a minimum of two months later gets a reply. But it's entirely outside your speedster's control how long it could take. If a reply took an hour in the real world your speedster has seen the equivalent of nearly four years (!) so by. If they took a day to reply, your speedster sees the equivalent of 94 years pass - and in all probability your speedster died waiting for a reply.
From your speedster's point of view communicating with the ordinary world would be like a person on land waiting for a letter from a sailor in the days before radio and telegraph. A letter might come, it might not. It would be months between letters or even years.
The Alternative ...
Your Speedsters can't get much from communicating with statues like humans. But consider a world where AI's exist and are able to communicate and think much faster than humans.
They'd be a natural for your speedster to communicate with.
Note a typical display can refresh at speeds no faster than about 200 Hz (200 times a second). So the shortest period an AI would be able to send a new message to your speedster would be the equivalent of about 7 minutes to your speedster. A more conventional 60 Hz display would bring that up to about 25 minutes between messages.
Note this also works the same way for your speedster trying to e.g. learn something from an internet page. It takes at least a second to refresh a typical page including time to fetch it, so your speedster has to wait an entire day (from her point of view) to read the next page. Difficult to learn with that problem.
Turning paper would be just as problematic as turning it too fast would shred it, or worse, so your speedster would need to be very patient.
If 1 second is 24 hours, speed up factor is 86,400 - physics will instantly kill her:
- She can't move. If she were to walk (at 5kph typical, subjective speed) she would be instantly incinerated, because her actual speed would be over 400,000kph. Meteors of solid rock vaporize in the upper atmosphere at small fractions of this speed. Basically any attempt at moving will kill her, so she can't get to food or water. Other factors notwithstanding, she would die of thirst in about 3 days subjective or about 3 seconds real time.
- She can't breathe. Her metabolism requires her to take about 15 breaths per minute at velocity 1m/s subjective, or about 20,000 breaths/second at 300,000kph real time. This is way beyond hypersonic - it's insane. Due to friction and fluid dynamics, to her air would have the viscosity of cold treacle. Other factors notwithstanding, she would die of suffocation within about 3 minutes subjective time, or about 2 milliseconds real time
- She can't live. Never mind breathing, her blood couldn't move any faster through her circulatory system than ours. Due to fluid dynamics and turbulent flow friction, her heart wouldn't be able to pump blood at the required velocities needed to keep her conscious. She would pass out within about 5 seconds subjective time or about 50 microseconds real time.
The idea of her communicating, or doing anything at all actually, is a non-starter.
Let's start by hand-waving all the physics problems like friction, momentum, etc. We can use a made-up term that is totally original and not inspired by other fictional speedsters.
VelocityStrength or something along those lines.
So assuming that VS takes care of all the (billions) little problems that come from such a speedster, like breaking keyboards, running out of air and completely destroying everything around from extreme air pressure changes, now our speedster, let's call him Barney Warren, has several things to take care of.
Since the mechanics of this speedster as a baby are ridiculous, and you didn't specify if the power is natural or obtained later, I will only take into account adult life. I will aslo assume that this speedster ages in real time, and not in subjective time, because otherwise they'd die of old age within hours.
Time factor: 1 subjective hour = 86400 real hours
Until Barney succeeds at communication, nobody knows he exists. Unless he is willing to stand still for days (one day = one second), nobody will ever see him. Any sound he makes would be far too high-pitched to be heard by humans or animals, and any physical contact would either instantly destroy the target, or be protected by VS and do basically nothing.
The speedster then needs to change something in the environment to communicate. Writing messages is obvious, whether it is on paper, in the sand, by email, etc.
But if he wants the communication to be two-sided, he needs to be incredibly patient. What is the most likely to happen, provided this speedster is a good guy, is that he will steal a lot, but people will like it. If he is a villain, we'd all be conquered or killed within a day.
Just like everyone else, he has needs. As for food and water, his needs are probably roughyl equal to 86400 people for the same timespan. That's a LOT of ressources, and he has to obtain them without people's consent, because he'd die of hunger before anyone could say yes (at least until he establishes a decent rotation, like ask 100 000 people and pay them, then come back to the first to collect after he gave consent, etc)
I think the most logical course of action is to go do jobs hat are time sensitive, and steal the pay (while leaving a written explanation). Barney finds some place where people are doing physical work. He then uses his near-infinite time to figure out how much the owners are paying, calculates the total (hourly pay * number of workers * time to completion), then does the entire thing instantly (from our perspective) and steals this precise amount of money. While technically illegal, I'm pretty sure paying the same amount to get the work done instantly instead of over months would leave many owners very happy.
Then he can "buy" things the same way. Steal what you need, figure out the price, leave the correct aount of money with a post-it on it explaining exactly what you did. Some people literally do the same in gas stations if the clerk is busy and they are in a hurry, but in seconds instead of milliseconds.
Considering the incredibly rate at which Barney would do those operations, pretty much everyone would be aware of him instantly. After a very short time, some people would start making official offers to him (X amount of money/food/etc if you come do this for me), which would take into account the incredibly fast work, and would probably pay more.
Not everyone would like it. Barney would be "stealing" many more jobs than any illegal alien ever did. But I assume that by catching bad guys or saving lives every now and then, Barney could keep a relatively nice reputation and be liked overall.
As for personal connexions, it's just impossible. Long distance relationships have a much lower rate of success because distance, and delay in communications, are a huge burden on relationships. Imagine a guy who would have to wait months at a time even for the simplest answer to a question?
I'm sorry to say, Barney will never be friends with Risco and Katelyn.
As for my personal opinion, while he might not turn into a total villain, he will definitely not stay that nice for long. Nobody can stop, threaten or even lecture him. Sooner or later, he will start to work less and/or take more, and at some point will straight up just take. Nobody is holding him accountable anyway, and physical work will get boring/tiring extremely fast, especially alone. Keep in mind that while the work is done within minutes, Barney had to do maybe months or years of work, on what probably looks like a normal person's Schedule (8-12hours a day), without any help, teamwork or person bringing refrreshments. And as opposed to us, he can't look forward to being done after a quick 45 years.