3 ms·

I sometimes daydream about what would happen if I were suddenly transported back in time -- but with everything on my person intact (iPhone included). Step one

by nlh 3y ago

I sometimes daydream about what would happen if I were suddenly transported back in time -- but with everything on my person intact (iPhone included). Step one in this daydream is always "Crap, no internet for 100 years -- if only I had all of Wikipedia cached". Check! :) Step 2 of course is figure out how to fashion some sort of charging system so my magical godlike pocket super abacus continues to function after ~days, but I'm making the bold assumption that somewhere in the annals of Wikipedia I can figure that out.

agrimonyhal 3y ago
You might enjoy this book: https://www.goodreads.com/book/show/39026990-how-to-invent-everything https://www.goodreads.com/book/show/39026990-how-to-invent-e...
guntars 3y ago
7 cell copper-zinc wet electrolyte battery - https://en.wikipedia.org/wiki/Penny_battery https://en.wikipedia.org/wiki/Penny_battery
hgomersall 3y ago
There's some sweet spot where technology is relatively easy to improve upon with Wikipedia, but one can also find wires and generators. Some time in the first half of the 19th century is probably good. It gets easier if you're allowed a solar charger to take with you, then you can improve tech in loads of ways (though probably best to restrict yourself to post enlightenment if you want to keep intact).
Terr_ 3y ago
> If I were suddenly transported back in time It'd be nice if there was a curated downloadable subset of Wikipedia pages for that kind of purpose. (Time-traveler in past, stranded/post-apocalyptic survival, history pages but only the text parts.) Even if only mundane events occur, it also represents a certain cross-section of user-interest. That said, one more daydream item to add to the pile: "What if I was somehow lost in space, what useful information could I provide for maybe locating my home-planet again?" ____ Without Wikipedia, the best I can think of are notable conditions that could help them filter existing records, often using ratios to avoid having to define measurement units, ex: 1. It's the 3rd planet from the Sun, the majority of it is covered with water, etc. 2. It has an unusually large single moon of 1/6 its mass. 3. The 5th and largest planet in the system has a little over 70% of all the (known) planetary mass. 4. The 5th planet is 5.2x further from the Sun than my 3rd planet. 5. The 6th planet still has notable rings which haven't decayed yet. With Wikipedia, perhaps I could tell them about pulsar maps or whatever. [0] [0] https://voyager.jpl.nasa.gov/golden-record/golden-record-cover/ https://voyager.jpl.nasa.gov/golden-record/golden-record-cov...
- qingcharles 3y ago
  I asked GPT4... Locating the Sun from an unknown position in space, especially if you're many lightyears away, would be a complex task. Here are some strategies you could use: 1. *Spectral Analysis*: Every star has a unique spectrum, and the Sun's spectral signature is well-documented. If you have the capability to perform spectral analysis on nearby stars, you could compare their spectra to that of the Sun. This, however, assumes you have a database of stellar spectra, including the Sun's, for comparison. 2. *Position of Known Stars and Constellations*: By observing the position of known stars and constellations, you might be able to estimate your location. This becomes more difficult the further you are from Earth, as the relative positions of stars change with distance, and familiar constellations may become unrecognizable. 3. *Parallax Measurements*: Parallax is the apparent shift in position of an object when viewed from different perspectives. Measuring the parallax of nearby stars compared to more distant background stars could help you triangulate your position. Knowing your position relative to the Milky Way galaxy would be essential in locating the Sun. 4. *Galactic Landmarks*: Identifying key features of the Milky Way, such as the galactic core, spiral arms, or specific nebulae, could help orient you within the galaxy. The Sun is located in the Orion Arm, about 26,000 lightyears from the galactic center. 5. *Radio Signals*: If your ship can detect radio signals, it might catch broadcasts from Earth. The Sun would be in the general direction of these signals. However, depending on your distance, these signals might be very weak or non-existent. 6. *Automated Stellar Navigation Systems*: Use any advanced stellar navigation systems on board. These systems could automatically identify stars and calculate your position relative to them. 7. *Consult Star Maps and Databases*: If your ship has a database of star maps, you could use these to match up visible stars with known stars and work out your position relative to the Sun. 8. *Communication with Earth*: If communication with Earth is possible, getting assistance from ground-based observatories or space agencies would be invaluable. They could provide information based on your last known position and trajectory.
- rokkamokka 3y ago
  IIRC the fact that our moon is almost the exact same size as our sun when viewed from the surface is rather rare as well
Nextgrid 3y ago
> Step 2 of course is figure out how to fashion some sort of charging system so my magical godlike pocket super abacus continues to function after ~days In the good old days of USB 2 I'm sure you can figure out how to get a stable-enough ~5V power supply that would charge the smartphone. With USB-C you'd need to reinvent IC manufacturing and figure out a needlessly-fragile and overcomplicated protocol before the phone would even accept any power. Yay for progress!
- RockRobotRock 3y ago
  are you suggesting we make the USB standard so easy a caveman could do it?
- infinityio 3y ago
  To my understanding, there are ways of wiring a USB-C cable such that only four contacts are active, and behave as a USB 2 cable? (although you can only do USB 2 charging over it, so no PD)
- ianburrell 3y ago
  USB-C works without USB-PD. Plain USB-C is simpler than USB-A since it supplies 1.5A or 3A based on resistors. The USB-C to USB-A and microUSB adapters are just resistors to use legacy USB. Legacy USB power is fairly complicated with different standards for 500mA, 1A, and 2.4A power. The reason it looks simple is that cheap chip is in every charger and device. You can probably provide at least 2.4A 5V on USB-A, just like providing 3A 5V would be fine with USB-C.
- lxgr 3y ago
  USB-C is a superset of USB-A/B, so you can use exactly the same simple protocol: A short of the D+ and D- pins, per USB Battery Charging. For a USB-C sink, you don't even need any resistors beyond that, let alone USB-PD. For a USB-C source to be able to charge a legacy USB-B sink, all you need is a single 56 kOhm resistor.
dylan604 3y ago
one of the other apps to I would want to have would be an astronomy app. also, in your "on my person" thing to consider would be a solar charger. otherwise, when the natives come to you after the battery dies, your magic abilities are less godlike.

by nlh 3y ago

agrimonyhal 3y ago

You might enjoy this book: https://www.goodreads.com/book/show/39026990-how-to-invent-everything https://www.goodreads.com/book/show/39026990-how-to-invent-e...

guntars 3y ago

7 cell copper-zinc wet electrolyte battery - https://en.wikipedia.org/wiki/Penny_battery https://en.wikipedia.org/wiki/Penny_battery

hgomersall 3y ago

There's some sweet spot where technology is relatively easy to improve upon with Wikipedia, but one can also find wires and generators. Some time in the first half of the 19th century is probably good. It gets easier if you're allowed a solar charger to take with you, then you can improve tech in loads of ways (though probably best to restrict yourself to post enlightenment if you want to keep intact).

Terr_ 3y ago

> If I were suddenly transported back in time It'd be nice if there was a curated downloadable subset of Wikipedia pages for that kind of purpose. (Time-traveler in past, stranded/post-apocalyptic survival, history pages but only the text parts.) Even if only mundane events occur, it also represents a certain cross-section of user-interest. That said, one more daydream item to add to the pile: "What if I was somehow lost in space, what useful information could I provide for maybe locating my home-planet again?" ____ Without Wikipedia, the best I can think of are notable conditions that could help them filter existing records, often using ratios to avoid having to define measurement units, ex: 1. It's the 3rd planet from the Sun, the majority of it is covered with water, etc. 2. It has an unusually large single moon of 1/6 its mass. 3. The 5th and largest planet in the system has a little over 70% of all the (known) planetary mass. 4. The 5th planet is 5.2x further from the Sun than my 3rd planet. 5. The 6th planet still has notable rings which haven't decayed yet. With Wikipedia, perhaps I could tell them about pulsar maps or whatever. [0] [0] https://voyager.jpl.nasa.gov/golden-record/golden-record-cover/ https://voyager.jpl.nasa.gov/golden-record/golden-record-cov...

qingcharles 3y ago
I asked GPT4... Locating the Sun from an unknown position in space, especially if you're many lightyears away, would be a complex task. Here are some strategies you could use: 1. *Spectral Analysis*: Every star has a unique spectrum, and the Sun's spectral signature is well-documented. If you have the capability to perform spectral analysis on nearby stars, you could compare their spectra to that of the Sun. This, however, assumes you have a database of stellar spectra, including the Sun's, for comparison. 2. *Position of Known Stars and Constellations*: By observing the position of known stars and constellations, you might be able to estimate your location. This becomes more difficult the further you are from Earth, as the relative positions of stars change with distance, and familiar constellations may become unrecognizable. 3. *Parallax Measurements*: Parallax is the apparent shift in position of an object when viewed from different perspectives. Measuring the parallax of nearby stars compared to more distant background stars could help you triangulate your position. Knowing your position relative to the Milky Way galaxy would be essential in locating the Sun. 4. *Galactic Landmarks*: Identifying key features of the Milky Way, such as the galactic core, spiral arms, or specific nebulae, could help orient you within the galaxy. The Sun is located in the Orion Arm, about 26,000 lightyears from the galactic center. 5. *Radio Signals*: If your ship can detect radio signals, it might catch broadcasts from Earth. The Sun would be in the general direction of these signals. However, depending on your distance, these signals might be very weak or non-existent. 6. *Automated Stellar Navigation Systems*: Use any advanced stellar navigation systems on board. These systems could automatically identify stars and calculate your position relative to them. 7. *Consult Star Maps and Databases*: If your ship has a database of star maps, you could use these to match up visible stars with known stars and work out your position relative to the Sun. 8. *Communication with Earth*: If communication with Earth is possible, getting assistance from ground-based observatories or space agencies would be invaluable. They could provide information based on your last known position and trajectory.
rokkamokka 3y ago
IIRC the fact that our moon is almost the exact same size as our sun when viewed from the surface is rather rare as well

Nextgrid 3y ago

> Step 2 of course is figure out how to fashion some sort of charging system so my magical godlike pocket super abacus continues to function after ~days In the good old days of USB 2 I'm sure you can figure out how to get a stable-enough ~5V power supply that would charge the smartphone. With USB-C you'd need to reinvent IC manufacturing and figure out a needlessly-fragile and overcomplicated protocol before the phone would even accept any power. Yay for progress!

RockRobotRock 3y ago
are you suggesting we make the USB standard so easy a caveman could do it?
infinityio 3y ago
To my understanding, there are ways of wiring a USB-C cable such that only four contacts are active, and behave as a USB 2 cable? (although you can only do USB 2 charging over it, so no PD)
ianburrell 3y ago
USB-C works without USB-PD. Plain USB-C is simpler than USB-A since it supplies 1.5A or 3A based on resistors. The USB-C to USB-A and microUSB adapters are just resistors to use legacy USB. Legacy USB power is fairly complicated with different standards for 500mA, 1A, and 2.4A power. The reason it looks simple is that cheap chip is in every charger and device. You can probably provide at least 2.4A 5V on USB-A, just like providing 3A 5V would be fine with USB-C.
lxgr 3y ago
USB-C is a superset of USB-A/B, so you can use exactly the same simple protocol: A short of the D+ and D- pins, per USB Battery Charging. For a USB-C sink, you don't even need any resistors beyond that, let alone USB-PD. For a USB-C source to be able to charge a legacy USB-B sink, all you need is a single 56 kOhm resistor.

dylan604 3y ago

one of the other apps to I would want to have would be an astronomy app. also, in your "on my person" thing to consider would be a solar charger. otherwise, when the natives come to you after the battery dies, your magic abilities are less godlike.