Difference between revisions of "Talk:1580: Travel Ghost"

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(Reference to Oracle as it relates to NP hardness of TSP?)
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There's actually a very similar mechanism in the game Canvas Rider, where the best times on a track (it's a bike racing game with stick figures) can be clicked and a ghost that takes the same path with the same speed as those people appears and moves while you do. In fact, they actually look somewhat similar to the ghost in panel 4. [[Special:Contributions/108.162.226.149|108.162.226.149]] 13:17, 22 September 2015 (UTC)
 
There's actually a very similar mechanism in the game Canvas Rider, where the best times on a track (it's a bike racing game with stick figures) can be clicked and a ghost that takes the same path with the same speed as those people appears and moves while you do. In fact, they actually look somewhat similar to the ghost in panel 4. [[Special:Contributions/108.162.226.149|108.162.226.149]] 13:17, 22 September 2015 (UTC)
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I strongly suspect this also references the concept of the Oracle machine as it relates to the NP hardness of the traveling salesman problem.  TSP is in the complexity class NP Complete, and part of the most common proof that it is NP hard involves showing that it reduces to a polynomial time algorithm (and hence potentially practically computed) if there exists an oracle that can tell you if a route is optimal (the fastest) in constant time.  I have never edited here before and don't know all the etiquette, so I leave it to a more experienced editor to consider this in the main article. [[Special:Contributions/108.162.219.173|108.162.219.173]] 22:17, 22 September 2015 (UTC) tomb

Revision as of 22:17, 22 September 2015

Racing Ghosts is a refference to Mario Kart ẞ qwertz (talk) 12:50, 21 September 2015 (UTC)

This seems like a bit of a stretch to me. 173.245.55.118 13:35, 21 September 2015 (UTC)
It's not a reference to Mario Kart specifically (lots of racing games have ghosts), but that's basically what this is doing - translating the concept of racing ghosts to the real world.--108.162.216.70 13:50, 21 September 2015 (UTC)
Well, there are some fitness running apps that support a ghost runner mode, so you run against your best time and get updates if you are in front or behind of your „ghost“. Without actually being able to prove it, I believe (and always assumed) this idea is actually inspired from racing games like Mario Kart. 162.158.115.36 13:56, 21 September 2015 (UTC)
Also, see https://en.wikipedia.org/wiki/Time_attack#Video_games sirKitKat (talk) 14:11, 21 September 2015 (UTC)

So in the title text, is he being replaced with the ghost who always *ahem* comes last? --SaturNine (talk) 12:53, 21 September 2015 (UTC)

I agree. 173.245.50.154 13:36, 21 September 2015 (UTC)
Women prefer men that are stuck in traffic?? 162.158.90.235 19:17, 21 September 2015 (UTC)
Nah - just someone who takes the "scenic" route. 108.162.215.17 19:50, 21 September 2015 (UTC)
I love that this could be a reference to the move Ghost. Great. -Jeff (talk) 19:51, 21 September 2015 (UTC)

Is this the first time Cueballs children were shown? ẞ qwertz (talk) 17:22, 21 September 2015 (UTC)

I don't know if it's worth mentioning that this appears to be a width-first (route-)search algorithm. A memory-heavy but guaranteed 'perfect' solver of best routing, at every point of choice (from the very first, how you start the journey), all possible/practical travel options are explored (including taking a journey in the 'wrong' direction, or waiting for the non-stop train that is not the first to arrive, to take advantage of connections with faster transport links), in parallel according to the total time (or other measure of efficiency) yet taken on each iteration. Unless any 'ghost' arrives at a node that has already been visited by a 'ghost', when it need not continue. Eventually, the most efficient son-of-a-son-of-a-son...-of-a-son-of-a-ghost will reach the destination, indicating the 'correct' answer. At least within the limits of the split-and-propogate algorithm, and the amount of parallelisation available to devote to the problem. (See also the multiple-overlayed 'searches' performed by two-minutes-of-Nicholas Cage, in the near-climactic scene in the film 'Next' (beware spoilers!).) 141.101.99.12 22:38, 21 September 2015 (UTC)

Are you aware if such an app exists in real life? I'd be interested in trying to program one (albeit with less tangible ghosts). LowHangingFruit 14:19, 22 September 2015 (UTC)

Will his children have half-siblings that are fathered by the ghost that has replaced him in the bedroom? Or are ghosts infertile?108.162.215.170 04:07, 22 September 2015 (UTC)

Doesn't light do this according to some theory, sending out "investigation waves / photons" to determine the quickest way to get anywhere? I'm no expert on this, just some food for thought... 162.158.90.249 11:57, 22 September 2015 (UTC)

Not really - or at least not real. There may be some "potential photons" in some attempts to describe some quantum-based theory ... but there will certainly be no investigation photons after wave collapse. -- Hkmaly (talk) 12:12, 22 September 2015 (UTC)
"Everything we call real is made of things that cannot be regarded as real." - Niels Bohr. (Whether or not he's ultimately right, it's an explanation.)141.101.99.12 13:48, 22 September 2015 (UTC)

If the simulations explore all travel possibilities, how long will it be until bike ghost gets run off the road by bus ghost? Or flattened by texting driver ghost? 198.41.238.33 12:30, 22 September 2015 (UTC)

This reminds me of an Android (and probably iOS) game "Does Not Commute" which takes the classic 'ghost competitor' behaviour (note: 108.162.226.149, below, that it's a common thing) and makes them solid. You run (different) 'missions'/commutes across the playing arena with a succession of new vehicles, each time finding that all your previous commutes are happening, simultaneously, creating obstacles and hazards. You can collide with (or end up being run into by) another vehicle, replaying the path you set it upon in a previous round, and this causes you to rebound. (But there's no 'kickback' when contact is made with your prior 'self', which sticks solidly to its pre-played path. Thus no need to deal with contradictions and temporal paradoxes by deflecting a past-self thus potentially changing the entire arena (for good or bad) for every other attempt you made, trying to avoid everything else.) Worth a dabble, perhaps, but don't get addicted to it! 141.101.99.12 13:48, 22 September 2015 (UTC)

There's actually a very similar mechanism in the game Canvas Rider, where the best times on a track (it's a bike racing game with stick figures) can be clicked and a ghost that takes the same path with the same speed as those people appears and moves while you do. In fact, they actually look somewhat similar to the ghost in panel 4. 108.162.226.149 13:17, 22 September 2015 (UTC)

I strongly suspect this also references the concept of the Oracle machine as it relates to the NP hardness of the traveling salesman problem. TSP is in the complexity class NP Complete, and part of the most common proof that it is NP hard involves showing that it reduces to a polynomial time algorithm (and hence potentially practically computed) if there exists an oracle that can tell you if a route is optimal (the fastest) in constant time. I have never edited here before and don't know all the etiquette, so I leave it to a more experienced editor to consider this in the main article. 108.162.219.173 22:17, 22 September 2015 (UTC) tomb