Some years back I was in a D&D campaign where doppelgangers became a major ongoing concern. It turned out that in that case doppelgangers built up their image of the person they wanted to mimic through careful observation, but thanks to the general prudishness of society doppelgangers rarely ever caught glimpses of peoples' genitals. So we ultimately came up with the "crotch check" system. Doppelgangers usually couldn't form plausible genitalia.
this post was submitted on 10 May 2025
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Does my doppelgänger go to my workplace and do my job?
If not, that’s the giveaway. If he does, I leave him to it and go read a book in the park.
Don't let my boss know that I know this.
Congrats, your doppelganger goes to your job and gets you fired. The monkey's paw strikes again.
In that case, that's the giveaway
I'd sign a payload using my private key that my doppelganger doesn't have.
Same as I do now, passwords. Unless they inherited my memories, in which case who's to say I'm not the doppelganger?
Lol, I think passwords are very trival to get.
I mean, they got the ability to look like you, you gotta assume they can get CCTV footage of you typing your passwords.
I don't see how looking like me would help them get CCTV footage, unless it's through some sort of supernatural means. And even if they could find footage of me entering a password, they'd be hard-pressed to extract individual keystrokes from a typical CCTV quality recording. Perhaps it's technically possible, but it's certainly not trivial.
My friends would notice immediately when we started playing any fps games after work. I don't wanna toot my own horn too much, but I am decently above average at fps games and my friends tend to like having me on their team since I am almost always top fragging.
If they aren't weirdly good at shooters people are gonna get suspicious quick lol
Nice try, Doppelganger!
Save it for queen dopplepopolis!
I dub thee Sir Phobos, Beater of Ass.
Simple. I kill my doppelgänger, if he wins he wanted it more.
There could be only one Rusty Shackleford.
…Dwight?
Be too useless to merit a doppelganger. To paraphrase zhuangzi, few know the usefulness of uselessness.
I'm the one who knows how to use Lemmy.
Well, easy, I'm the one without the moustache.
They can't type anything on my phone because I use Thumb-Key.
If they only mimic me and have some knowledge based on what is on my phone/online, they probably don't speak the same foreign languages as I on the same level. So I could authenticate myself by proving that I speak those languages.
I would be signing all my communications cryptographically and sharing a key in person so people can validate whether a message not delivered face to face is really from me.
Cryptography is the only correct answer
I’ve never met anyone who looks like me so I don’t worry about it
Does my doppelganger have the same tastes as me? If not, then only the real me would walk around with Amy Rose and/or Sonamy (Sonic x Amy Rose) wallpapers on all his devices without the slightest hint of shame or embarrassment.
If he has the same taste, then we'll play SoulCalibur 3 together.
Assuming i'm caught by someone that know me well, just ask me about the slight red patch on my face and tell me it's allergic.
Secret handshake
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Does my doppelganger have the same knowledge I have, or just the same outward physical characteristics?
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Does my doppelganger possess the same physical objects I do, like a physically-identical copy of a cell phone, say?
Think like identity theft, they transform their body to match your body, and their voice matches your voice. The only way they can get detected is if they get arrested and the authorities use a machine to verify someone's true identity.
Don't forget, this is the information age, they might have surveillance capabilities to monitor the way you talk, and be able to record your authentication methods.
Hmm. I'm not entirely clear here...are you saying the answer to both of the two questions is "no"? I mean, you didn't explicitly say that the doppleganger has the same knowledge or the same possessions, but you also didn't explicitly say that they didn't.
Does my doppelganger have the same knowledge I have, or just the same outward physical characteristics?
They don't have a replica of your brain, if that's what you are asking.
They just look the exact same as you, along with your voice.
But they might have hacked your phone and started listening in to be able to mimic the way you talk.
Does my doppelganger possess the same physical objects I do, like an identical copy of a cell phone, say?
No, but they could just steal your phone, or better yet, just kidnap you and lock you away then steal your clothes too.
They don’t have a replica of your brain, if that’s what you are asking.
Okay. In that case, I think that I'd probably use that, since there will definitely be information that I could show other people that only I know. Passwords, past private memories with people I know, that sort of thing. Maybe if one is optimistic, my doppleganger could guess or somehow obtain one or two, but if we do a number of these, I should be able to pass many more of these than my doppleganger.
how about i just fuck them then 🤗
That begs the age old question... would that be incest, or masturbation?
"What's something only the real me would know?"
Assuming they haven't mugged me, I'd just sign into one of my accounts with my yubikey.
So far, I've been compromised twice. The second, hijacking my phone via sim swap, means there's a doppleganger who is pretty good at being me. Luckily I was able to restore my phone to me in about 1/2 hr because I still had a landline phone at the time, and so got ahold of my provider quickly.