43

Cholera. If you want to emphasize methodical scientific method you could do worse than to copy John Snow, one of the founders of modern epidemiology. 150th Anniversary of John Snow and the Pump Handle John Snow, M.D. (1813--1858), a legendary figure in epidemiology, provided one of the earliest examples of using epidemiologic methods to identify risk for ...


38

Scurvy. It spreads mostly in ocean going navy, but not necessarily. The time traveler kind of suspects the disease, but does not remember the symptoms (can you?), apart from teeth falling out. He also knows the cure is vitamin C, and definitely knows that lemons (or similar) would be very good, but... there are no lemons. Nobody knows such fruits when ...


21

Any Gram Positive Bacterial Infection Works A variation of Pneumococcal, Listeriosis, or Diphtheria infections would probably be the most likely cases of gram positive bacterial infections with the potential to be described as both an outbreak and potentially dangerous. While viruses need specialized vaccines, most bacterial infections can be treated with ...


8

I’m going to slightly challenge your premise here by arguing that: The exact disease does not matter much given your constraints. Put simply, if you want an epidemiological solution (and you seem to be asking for that), all that matters is that the means of transmission of the disease be readily discoverable by someone with a layman’s understanding of germ ...


5

The sender(s) will solve your problems for you. The people in the future will already know how to do all this. They will know how to send and receive, and will send that information in the very first transmission. So how do they send a message to a past that doesn't already have the tech? They downgrade their signal and send it back to a regular modern day ...


4

Society gets a lot more honest for good and ill. Crimes of passion increase slightly. People still have individual perspectives but you can't hide things like infidelity, abuse, or indiscretion. so people will still commit murder, assault, and other crimes of passion. Everyone still has their own personal narrative. Theft and fraud become basically non-...


3

Receiving considering time and space The thing is that time and space are linked. Even without that link it's obvious there is a problem. The moment you travel back a day, you'll fly in outer space, very roughly that's 259000 km (1608000 miles) from the Earth (quite a lot of rounding errors possible, but you get the idea). Unfortunately our solar system is ...


3

Build around the limitations of the transmitter You're right, the receiver is the easy part. You want a system that will tolerate small inaccuracies in time and space since your transmitter may not be able to send a signal from the exact right place. In the future there might be a military base on the location of your receiver and the transmitter has to send ...


3

Parasites are the way to go. Most bacterium can't be cured without antibiotics, or other microscopic creatures or help. The best bet would be viruses and/or parasites. Malaria might be a good choice if it was set closer to the equator, in a hotter, more humid area. The major signs of a disease are fevers, chills, aches, and the like. Often times coughing. ...


3

First, the benefits. Historians, physicists, astronomers, bioligists... pretty much every science-based profession will have the knowledge to develop origin stories, whether it be the beginning of life or the universe. Technology will definitely benefit as a result. Next, the privacy concerns. Privacy is dead. Every moment of everyone's life could be under ...


3

They have forest, tools, and skills. They can make pretty much anything that doesn't require metal. Pegs can sub for nails, in many ways, and if one or more have experience in Japanese/southeast Asian woodworking, the need will be very small in any case. They might well start with huts resembling those from the Gilligan's Island TV series, as a first step ...


2

That disease caused by ergot fungus rye contamination. Just have him point out the bread is making their toes drop off and making them act nuts .


2

Buy this radio with three dollars, tune it to any frequency that records their broad casts and note your location, frequency, and time. Post this information somewhere on the internet. The future sender will send you a message at that frequency by playing a signal that destructively interferes with the signal you would normally receive, and then add the ...


1

I mean, just have future you start talking all about the inner workings of past you's past. If a person started telling me about my inner thoughts and whatnot, then I'd be pretty convinced. A Q&A-based conversation between them would likely be enough.


1

Without knowing the rules of time travel in your world... The unfortunate truth about time travel is that, insofar as we know, it can't happen. That means we're inventing an idea, but we're missing the rules of your world that are the foundation for the idea. (Normally we'd vote to close a question that doesn't have all the details, but this is your first ...


1

I would assume it isn't really important what your receiver is based on, radio waves, light or what ever. Since the future guys will know that and tweak there transmitter. Also less important should be the position, as long as it is well enough publicly known. I would argue your receiver would need some other hardware, to log as much information as possible....


1

The max 1 jump drive per ship seems like a strange limitation. I would not be satisfied with that in a movie, it makes no sense. Since you have no FTL communication or other ways of observing light that hasn't reached you, you can easily make a much more sensible explanation to why you can't have 2 drives: It's not the drive itself that's the limitation, it'...


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