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Positive Energy Warp Drive from Hidden Geometric Structures

arxiv.org

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Re: Positive Energy Warp Drive from Hidden Geometric Structures

#181

Post by drran »

nl wrote: post #135
drran wrote: post #117

Earlier quoted context omitted.

> Being able to send messages faster than the speed of light grants the ability to send messages to yourself in the past. No, it doesn't. Even if we will be able to communicate instantly (0 delay = infinite faster than speed of light), we will not be able to send a message to the past (negative delay).

It does. Read the numerical example on https://en.m.wikipedia.org/wiki/Tachyonic_antitelephone

1) It's not applicable for this kind of drive. Isn't?

2) It's an unsolved problem, which waits for a correct solution.

3) Next time, please read what you are posting, please.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#182

Post by nwallin »

drran wrote: post #181
nl wrote: post #135

Earlier quoted context omitted.

It does. Read the numerical example on https://en.m.wikipedia.org/wiki/Tachyonic_antitelephone

1) It's not applicable for this kind of drive. Isn't? 2) It's an unsolved problem, which waits for a correct solution. 3) Next time, please read what you are posting, please.

1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery!" and hands you an envelope from yourself from the future.

2) It's an unsolved problem because it's built on a foundation which is also an unsolved problem -- namely faster than light travel/communication. If -- if -- we solve the problem that it's built on, all indications are that sending a message to your past will become possible.

That being said, I expect that it's impossible because I expect that FTL travel/communication is impossible.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#183

Post by nl »

nwallin wrote: post #182
drran wrote: post #181

Earlier quoted context omitted.

1) It's not applicable for this kind of drive. Isn't? 2) It's an unsolved problem, which waits for a correct solution. 3) Next time, please read what you are posting, please.

1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery…

These responses are correct.

I'll add: 3) yes I read it. It's an example Einstein created, so possibly worth responding to the points made there rather than attacking me for "not reading it".

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#184

Post by drran »

nwallin wrote: post #182
drran wrote: post #181

Earlier quoted context omitted.

1) It's not applicable for this kind of drive. Isn't? 2) It's an unsolved problem, which waits for a correct solution. 3) Next time, please read what you are posting, please.

1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery…

1) It's formula for time dilution. It's not applicable for a warp drive, because Alice will be shielded from relativistic effects, so no time dilution will occur. Alice's space will be dragged at speed > c, but Alice will live a normal life at normal speed, like a passenger in a supersonic airplane is protected from supersonic effects.

2) It's an unsolved problem because formula is defined for [0..c] only and for EM communication only. For a•v = c² it predicts dT=0, so time will stop for unshielded Alice, like it stops for photon, so she will not be able to communicate at all. For a•v > c², the formula is not defined at all (it is the unsolved problem). In reality, we expect to see Cherenkov radiation. In theory, according to this formula, EM processes should go in reverse, which is not possible at all, because it requires all photon emitted by Alice to reverse their direction and hit Alice at her new location.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#185

Post by drran »

nl wrote: post #183
nwallin wrote: post #182

Earlier quoted context omitted.

1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery…

These responses are correct. I'll add: 3) yes I read it. It's an example Einstein created, so possibly worth responding to the points made there rather than attacking me for "not reading it".

If you read it and understood it, can you show us how to apply this formula to the warp drive, please? I cannot ask Einstein, obviously.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#186

Post by native_samples »

pbhjpbhj wrote: post #126
native_samples wrote: post #114

Earlier quoted context omitted.

Star Trek's tech vision is astounding. How many things in it have actually been built? I count: • Tablets (the padds) • VR "holodecks" • Computers that you can talk to and ask questions • "Tricorders" (smartphones?) • Turbolifts ( https://www.dezeen.com/2017/07/12/thyssenkrupp-unveils-world... ) Maybe we'll get to add a warp drive to the list by the time I die. What else?

Communicators would be something like Bluetooth earpieces. You've got Tricorders wrong, they're a generalized non-contact diagnostic tool; someone was working on one but it was just a load of diagnostic devices stuck together. We've got body temperature, and pulse is doable, but not sure what else can really be added to a Tricorder, maybe a tiny mass-spectrometer gets you part way there.

Is it so wrong? My phone can:

- Identify places and objects with the camera and give me data about them (Google Lens)

- Plot graphs of the local geomagnetic fields, my exact position on earth (the built in compass and GPS)

- Plot graphs of local radio traffic, signal strengths etc (wifi scanners)

- Control other devices

- Diagnose medical conditions

Smartphones can do a lot already just with the sensors they already have.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#187

Post by native_samples »

aasasd wrote: post #174
native_samples wrote: post #114

Earlier quoted context omitted.

Star Trek's tech vision is astounding. How many things in it have actually been built? I count: • Tablets (the padds) • VR "holodecks" • Computers that you can talk to and ask questions • "Tricorders" (smartphones?) • Turbolifts ( https://www.dezeen.com/2017/07/12/thyssenkrupp-unveils-world... ) Maybe we'll get to add a warp drive to the list by the time I die. What else?

If you ever try to follow what a holodeck can and can't do, you easily see that few of our technology predictions can even hold a candle to it. There's some finger-waggling in-universe to explain away the discrepancy, but the ‘fact’ is that a holodeck would create matter with which you can interact, out of thin air, and expand this volume of matter seemingly for kilometers around, while purportedly being located in a…

Yes I know how the holodeck was hypothesised to work, but the actual goal of the deck was VR entertainment and we have that.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#188

Post by native_samples »

mr_gibbins wrote: post #159
dougmwne wrote: post #150

Earlier quoted context omitted.

Walking around with the sum total of human knowledge. That featured heavily in a lot of episodes where the ship carried around a library of everything and and could communicate back to the network on Earth for everything squared. Often problems were solved by database search algorithm. And the VR Holodeck is spot on actually. I was having moments where I was questioning how much better the experience really would be…

We used to have the sum total of human knowledge, or at least a good facsimile of it. Unfortunately, with the Internet as we know it transformed into a handful of walled gardens, finding detailed knowledge is increasingly difficult. Wikipedia is excellent, as usual. But it is an encyclopaedia, not a definitive source of original knowledge, and it remains the case that I can browse my modest (physical) bookshelves and…

Technically, all the books are online now thanks to Google's book scanning programme and Kindle. You might have to buy it to see the pages but that's OK. Of course Star Trek didn't have money, so ...

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#189

Post by evilduck »

ISV_Damocles wrote: post #161
effingwewt wrote: post #104

Earlier quoted context omitted.

It was most definitely one of if not the most central plot point of the series. Not sure how far you got, but the entire series including the prequels is worth a read imho.

Here's why I believe you are being downvoted: 1. The original topic was about Ender's Game only, not the entire series, so you basically shifted the goalposts. 2. More importantly, I think you are using the wrong literary terminology and you and the others are talking over each other. Where you say "plot point" I believe you meant "plot device." The Ansible is definitely the primary plot device that makes so much of…

FWIW I explicitly said "Ender's Game series". I think you're also redefining "plot point" to just be "plot". A plot point is simply an event that impacts what happens next. The reveal of FTL data happens late in the book but it is definitely both a plot point and a plot device.

For the greater series though, it's basically the core concept of the story arc's plot.

Re: Positive Energy Warp Drive from Hidden Geometric Structures

#190

Post by nwallin »

drran wrote: post #184
nwallin wrote: post #182

Earlier quoted context omitted.

1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery…

1) It's formula for time dilution. It's not applicable for a warp drive, because Alice will be shielded from relativistic effects, so no time dilution will occur. Alice's space will be dragged at speed > c, but Alice will live a normal life at normal speed, like a passenger in a supersonic airplane is protected from supersonic effects. 2) It's an unsolved problem because formula is defined for [0..c] only and for EM…

...what?

We're sitting here talking about how 1+2=3 and you're telling us that we're wrong, and that the sky is actually blue.

I have no basis to object to your argument, other than to tell you the thing you're arguing against clearly doesn't have anything to do with what the rest of us are talking about.

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