mikes@tekecs.UUCP (Michael Sellers) (07/27/86)
> > [...suggests a time travel experiment...] > > > > Comments? > > > > >< ...{ decvax!linus | seismo!harvard }!axiom!gts > > There are a lot of good arguments against the possibility of time travel, > and since you did ask for comments I'll risk the flames for posting a > "not-real-physics" article here. I think this falls into more of a "could be might be maybe physics" more than "not-real-physics," but who cares. This is one of those topics that is to make the speculative salivaries to overflow :-). > Time travel violates the conservation of mass and energy laws. Consider > transporting a 1Kg cube of gold 1 hour back in time. Then in the universe > of 1 hour ago, there is this extra 1Kg from nowhere, totally unaccounted > for. Similarly in the here and now, we lost 1Kg of mass, poof, just like > that. Mass wasn't conserved in our universe. That, as you should well > realize, is a big no-no. You have made an assumption here that is somewhat "temperocentric," and not necessarily true. You have assumed that the Universe is bound by the same linear time sense that we experience, at least with regard to the mass/energy conservation law. What if it is the case that, while mass and energy must be conserved, they do not have to be conserved with regard to time. That is, I can take a Kg of gold and project it 100 years in the future with no problem because, from the Universal point of view, I haven't gotten rid of it, merely transported it (though through time, not space). Thus it does not matter (in terms of conservation) if I take my gold and "send" it forward or backward in time, because it still exists, just "sometime" else. It would be possible, if this were true, to "rob" the future or past by taking all their gold and holding it here at this point in time. The consequences of this are rather mind-bending, especially in extreme cases (has anyone read the Stainless Steel Rat story where he has to go galavanting through time? there are some awfully interesting circular paths there regarding materials being around because they were sent from the future, so when the characters "get to" the future, they have them on hand to send back to the past...so where did they come from?). And of course just because we've beaten conservation doesn't mean we've gotten rid of the demon of causality. > There are lots of other arguments against it, causality and so forth. > > Doug Miller As for causality, there is always the possibility of multiple futures/pasts, or some even weirder possibilities with multiple universes, etc. Still, the original experiment would almost seem to be a CETI project for time travel ("if it [ever] exists, this is the only way we'll know") with the advantage that we only need to set it up for a few minutes or a day at most. If the spatial and temporal coordinates are recorded and distributed well enough (time capsules, newspapers, libraries, etc, etc), then anyone with time travel capabilities would be able to "send" something/someone back to the window of time during which we were watching. As a collateral question (and possibly too speculative for these august groups :-), if you were the one capable of sending something back, what (or who) would it be? And, if you were around when the watching was done, what do you think the effect on "current" society would be? (This reminds me of the end of the movie "The Time Machine," where we find the hero having gone back to the future (:-) in his machine, taking only three books with him...and we are left wondering which three out of his library he chose to take with him...) -- Mike Sellers UUCP: {...your spinal column here...}!tektronix!tekecs!mikes A path is simply a rut that's going your way.
melnick@unc.UUCP (Alex Melnick) (07/31/86)
In article <7489@tekecs.UUCP> mikes@tekecs.UUCP (Michael Sellers) writes: > As a collateral question (and possibly too speculative for these august >groups :-), if you were the one capable of sending something back, what (or >who) would it be? > > Mike Sellers Another question is: If you were in the future, knew about the experiment, and had the equipment to send some material or information back to the experimenters, WHY WOULD YOU SEND ANYTHING? (Douglas Adams is right: English grammar can't handle time travel.) It seems that in performing the experiment, we're relying on someone in the future not merely to be able to help us, but also to want to help us. Is this a reasonable assumption? Maybe. They might be interested in helping fellow scientists, etc., but on the other hand, what's in it for them? Sounds like a story (or three) in here somewhere. Alex ...!mcnc!unc!melnick (Still looking for M* Right.)
kaufman@nike.uucp (Bill Kaufman) (07/31/86)
In article <7489@tekecs.UUCP> mikes@tekecs.UUCP (Michael Sellers) writes: > As a collateral question (and possibly too speculative for these august >groups :-), if you were the one capable of sending something back, what (or >who) would it be? A nuclear bomb. Something that would, by "appearing" in that time, materialize in my grandfather. A computer & manual, destined for T.A. Edison in Menlo Park, NJ. The plans for "Opertion: Overlord" to die F^uhrer's office (excuse the attempt at an umlaut) in Berlin. In general, anything that would cause an identifiable, unavoidable mistake in time. Great way to verify whether we live in a "parallel" universe, or a "serial" one (cf. "Thrice Upon a Time," by (James P.?) Hogan). In article <83@unc.unc.UUCP> melnick@unc.UUCP (Alex Melnick) writes: >Another question is: If you were in the future, knew about the experiment, >and had the equipment to send some material or information back to the >experimenters, WHY WOULD YOU SEND ANYTHING? (Douglas Adams is right: English >grammar can't handle time travel.) What if the results could be changed by the exeriment (cf. Heisenberg's Un- certainty Principle :-)? BTW: It was Larry Niven who said that. Niven's example went something like: ----- "OK, I'll go back and deal with the dinosaurs. You go to Ford's lab, duplicate the duplicate, come back with the original duplicate, and I'll meet you a million years ago. Got that?" "Ummm,..." (Larry Niven, in one of the "Flight of the Horse" s.s's; and "Theory and Practice of Time Travel", in "All the Myriad Ways".) ----- (If anyone has the original quote, mind emailing it to me? TIA.) -Annoyingly, Bilbo. ___________________________________________________________________________ / DISCLAIMER: If I had an opinion, do you think I'd let my employers know? \ |E-MAIL: kaufman@orion.arpa or kaufman@orion.arc.nasa.gov | |FLAMES: Look, Ma, an asbestos mbox! (Gee, wish *you* had one, huh?) | |QUOTE: "Are you a commie? Good. Don't want no commies in my car. | | No Christians, either!" | +---------------------------------------------------------------------------+
purtill@petrus.UUCP (Mark Purtill) (07/31/86)
In article <289@axiom.UUCP>? Alex <...!mcnc!unc!melnick> writes: > In article <7489@tekecs.UUCP> mikes@tekecs.UUCP (Michael Sellers) writes: > > As a collateral question (and possibly too speculative for these august > >groups :-), if you were the one capable of sending something back, what (or > >who) would it be? > > > > Mike Sellers > > Another question is: If you were in the future, knew about the experiment, > and had the equipment to send some material or information back to the > experimenters, WHY WOULD YOU SEND ANYTHING? Consider a slightly different scenario. You know about the experiment and have a time machine, but *you know the experiment failed* (nothing showed up at the appropriate time). Now, are you willing send soemthing back? I doubt I would.... mark purtill (201) 829-5127 ^.-.^ Arpa: purtill@bellcore.com 435 south st 2H-307 ((")) Uucp: ihnp4!bellcore!purtill morristown nj 07960
tim@sunybcs.UUCP (Timothy Thomas) (08/01/86)
>It seems that in performing the experiment, we're relying on someone in the >future not merely to be able to help us, but also to want to help us. Is >this a reasonable assumption? Think about the logic in that. If we have to rely on somebody in the future to help us, then we will wait forever. If some technology is 'invented' or 'found' because of somebody in the future sending it to us, that would be a contradiction. Ok, fine, we now have some new tecnology. So in the future (since it has already happened), we send it back to ourselves again. Where did it originate??? There is no way any new knowledge from the future can enter into the present or past because of this knowledge must originate someplace, or be found (found meaning discovered on its own or invented, not handed to by some future scientist). -------- ____________ ____/--\____ \______ ___) ( _ ____) "Damn it Jim!, __| |____/ / `--' I'm a programmer not a Doctor!" ) `|=(- \------------' Timothy D. Thomas SUNY/Buffalo Computer Science UUCP: [decvax,dual,rocksanne,watmath,rocksvax]!sunybcs!tim CSnet: tim@buffalo, ARPAnet: tim%buffalo@CSNET-RELAY
jbuck@epimass.UUCP (Joe Buck) (08/03/86)
In article <556@sunybcs.UUCP> tim@gort.UUCP (Timothy Thomas) writes: >Think about the logic in that. If we have to rely on somebody in the >future to help us, then we will wait forever. If some technology >is 'invented' or 'found' because of somebody in the future sending >it to us, that would be a contradiction. >Ok, fine, we now have some new tecnology. So in the future (since it >has already happened), we send it back to ourselves again. Where did >it originate??? There is no way any new knowledge from the future >can enter into the present or past because of this knowledge must >originate someplace, or be found (found meaning discovered on its >own or invented, not handed to by some future scientist). Why would it be a contradiction? Causal loops are certainly strange, but they can be drawn on a Minkowski space-time diagram easily enough. "Contradiction" means that the statements "A" and "not A" are both true. For example, going back in time and killing my (younger) self cause a contradiction, where A is the statement "I exist at time t". But you're stating "knowledge must originate someplace (and time)?" as a postulate; it's not an axiom of logic. It only contradicts intuition. -- - Joe Buck {ihnp4!pesnta,oliveb,nsc!csi}!epimass!jbuck Entropic Processing, Inc., Cupertino, California
kaufman@nike.uucp (Bill Kaufman) (08/04/86)
[this was, I assume, sent to me accidentally] Date: Fri, 1 Aug 86 21:36:05 cdt From: caip!ihnp4!mmm!cipher (Andre Guirard) Message-Id: <8608020236.AA18362@mmm.SERCNET> To: floyd!caip!nike!kaufman Subject: Re: A Sane Man Proposes A Time Travel Experiment Newsgroups: net.physics,net.sci,net.philosophy,net.sf-lovers In-Reply-To: <451@nike.UUCP> References: <289@axiom.UUCP> <5723@lanl.ARPA> <7489@tekecs.UUCP> <83@unc.unc.UUCP> Organization: 3M Company, St. Paul, Minn. Cc: Status: R In article <451@nike.UUCP> you write: >In article <7489@tekecs.UUCP> mikes@tekecs.UUCP (Michael Sellers) writes: >...If you were the one capable of sending something back, what (or >>who) would it be? > >A nuclear bomb. Something that would, by "appearing" in that time, >materialize in my grandfather. A computer & manual, destined for T.A. Edison >in Menlo Park, NJ. The plans for "Opertion: Overlord" to die F^uhrer's >office (excuse the attempt at an umlaut) in Berlin. >In general, anything that would cause an identifiable, unavoidable mistake >in time. Great way to verify whether we live in a "parallel" universe, or >a "serial" one (cf. "Thrice Upon a Time," by (James P.?) Hogan). It's a good way to tell if you live in a parallel universe, but it's not a good way to tell if you live in a serial one, since the experiment would have a high probability of causing the experimenter never to have existed, or at least never to have conducted the experiment. Better to conduct the experiment on a smaller scale, then you can be sure that you'll be around to see the results. It seems like I've heard a theory to the effect that time travel can't exist not because it's theoretically impossible, but because the invention of time travel makes it possible to modify the past, making time travel never to have been discovered. Knowing how to travel in time is an unstable situation. -- ===+=== Andre Guirard /@ @\ ihnp4!mmm!cipher /_____\ ( @ @ ) My mission: to explore strange new words. \ _ / To seek out and utilize new applications. `-' To shovel snow that snow plows have shoved before. [And now, for the same, low price: a reply! ;-] OK, maybe I was stretching it. Something a little less severe, perhaps. Just so the experimenter will continue to exist--say, kill off someone current and famous. If you're in a serial universe, the event (person, in this case) will simply cease to exist. In other words, if nothing happens, you're in a serial universe! ;-) -Annoyingly, Bilbo. ___________________________________________________________________________ / DISCLAIMER: If I had an opinion, do you think I'd let my employers know? \ |E-MAIL: kaufman@orion.arpa or kaufman@orion.arc.nasa.gov | |FLAMES: Look, Ma, an asbestos mbox! (Gee, wish *you* had one, huh?) | |QUOTE: "Are you a commie? Good. Don't want no commies in my car. | | No Christians, either!" | +---------------------------------------------------------------------------+
dobro@ulowell.UUCP (Gryphon) (08/05/86)
The subject of multiple time lines was put forth in this story.
Short summary: the existance of an additional type of energy (tau) is
discovered. Seems that this energy is created (no comments :-}) whenever
another form of energy is released. This tau energy travels back in time
a distance directly proportional to the amount of energy. SO, these guys
who discovered this (who also happen to be hackers) design a machine to
monitor recption of this type of energy. Then they experiment by sending
forward (sorry, it can go forward or back, distance proportional ...)
and having the future people send messages back.
What they came up with is the idea as follows:
Picture a grid board, with a needle/hook/whatever stuck in at each point.
The 'thread' of relity is strung from point to point.
Now, move the thread in the past and that changes the points is connects
to. But, given enough time (dependend upon the severity of the change),
the 'thread' will head toward its original future. Thus there is an
elasticity to time.
Now, Hogan also came up with what the characters called the 'reset factor'.
This was basically that certain amounts of tau radiation will be consantlt
jumping back and forward and changing things, even as minor as the placement
of a sigle molecule. But, that can have unforseen affects. However, once
a change is made in the past, reality is retroactivley reset to
hav that as its past. Scary thought.
Sorry for length, but I think it was a neat idea. I will leave
all else (this contained no real spoilers to plot) to anyone who
wishes to read it.
Comments?
Gryphon
-------------------------------
Phone : (617) 937-0551
USMail: P.O.Box 8524, Lowell, Ma. 01853
Usenet: ...!{wanginst,masscomp,apollo}!ulowell!dobro
Moderator: mod-psi@ulowell.UUCP
Disclaimer: I am simply a figment of my imagination,
and can therefore not have an opinion.
"Far beyond human ability to classify, or comprehend..."taylor@glasgow.glasgow.UUCP (Jem Taylor) (08/05/86)
In article <451@nike.UUCP> kaufman@orion.UUCP (Bill Kaufman) writes: >In article <7489@tekecs.UUCP> mikes@tekecs.UUCP (Michael Sellers) writes: >> As a collateral question (and possibly too speculative for these august >>groups :-), if you were the one capable of sending something back, what (or >>who) would it be? > >A nuclear bomb. Something that would, by "appearing" in that time, >materialize in my grandfather. A computer & manual, destined for T.A. Edison >in Menlo Park, NJ. The plans for "Opertion: Overlord" to die F^uhrer's >office (excuse the attempt at an umlaut) in Berlin. >In general, anything that would cause an identifiable, unavoidable mistake >in time. Great way to verify whether we live in a "parallel" universe, or >a "serial" one (cf. "Thrice Upon a Time," by (James P.?) Hogan). > But, but, but if we do live in a parallel universes (sic), then you wouldn't notice any difference _in_this_parallel_ since this one is the one where the transmission into the past, failed. If there was a difference, it would be in a different parrallel universe, by definition. So 1) Time travel BACKWARDS into THIS PARALLEL doesn't work If the universe isn't parallels (sic again), no-one would notice the change because it would always have been that way. Ursula Le Guin wrote an excellent book - 'The Lathe of Heaven' ? - which treats this problem, in the context of some-one who can dream reality different. When he wakes up, everyone else has already forgotten the 'real' past, and remembered the 'new' past which is consistent with the new present. Our hero almost goes crazy ... So 2) Time travel DOES WORK but NO-ONE EVER NOTICES ... -Jem. -- -------------------------------------------------------------------------------- JANET: ' , ' , ' taylor@uk.ac.glasgow.cs ' ___ , ' USENET: , / | \ , { uk }!cs.glasgow.ac.uk!taylor ' -o| Royal Mail: , ' (J=) ' , J.A.Taylor ~~~~~~~~~~~~~~ Computer Science <>< 17 Lilybank Gardens ><> Jemima GB-GLASGOW G12 8QQ ><> Puddleduck "who says it doesn't rain on the west coast ?"
kaufman@nike.uucp (Bill Kaufman) (08/05/86)
In article <622@ulowell.UUCP> dobro@ulowell.UUCP (Gryphon) writes: >Short summary: the existance of an additional type of energy (tau) is >discovered. Seems that this energy is created (no comments :-}) whenever >another form of energy is released. This tau energy travels back in time >a distance directly proportional to the amount of energy. SO, these guys >who discovered this (who also happen to be hackers) design a machine to >monitor recption of this type of energy. Then they experiment by sending >forward (sorry, it can go forward or back, distance proportional ...) >and having the future people send messages back. Close enough: The radiation was (in every instance I can remember) sent back in time. Sending it forward in time is: a) No trick (read, "fun") at all. It happens all the time. This posting is going forward in time, and will reach you all at a time later than it was sent. b) Inconclusive. It doesn't show any real change in the universe. Say, in 1941, I send you (here/now) a note saying, "The Japa- nese bomb Pearl Harbor," would you do anything different? c) Impossible in the context of the story, I believe. [FYI, the information is passed as "bleeps", pulses of tau radiation, in a basic serial computer transmission, picked up at the other end by the same computer.] >Now, Hogan also came up with what the characters called the 'reset factor'. >This was basically that certain amounts of tau radiation will be constantly >jumping back and forward and changing things, even as minor as the placement ^^^^^^^ [See above.] >of a single molecule. But, that can have unforseen affects. However, once >a change is made in the past, reality is retroactively reset to >have that as its past. Scary thought. Yeah, but it doesn't happen often (it took the old guy YEARS to prove it even existed), and only interacts on an atomic level. Barely, at that. -Annoyingly, Bilbo. ___________________________________________________________________________ / DISCLAIMER: If I had an opinion, do you think I'd let my employers know? \ |E-MAIL: kaufman@orion.arpa or kaufman@orion.arc.nasa.gov | |FLAMES: Look, Ma, an asbestos mbox! (Gee, wish *you* had one, huh?) | |QUOTE: "Are you a commie? Good. Don't want no commies in my car. | | No Christians, either!" | +---------------------------------------------------------------------------+
franka@mmintl.UUCP (Frank Adams) (08/06/86)
>From: caip!ihnp4!mmm!cipher (Andre Guirard) >It seems like I've heard a theory to the effect that time travel can't >exist not because it's theoretically impossible, but because the >invention of time travel makes it possible to modify the past, making >time travel never to have been discovered. Knowing how to travel in >time is an unstable situation. I believe this suggestion is due to Larry Niven. Frank Adams ihnp4!philabs!pwa-b!mmintl!franka Multimate International 52 Oakland Ave North E. Hartford, CT 06108
markb@sdcrdcf.UUCP (Mark Biggar) (08/11/86)
In article <1693@mmintl.UUCP> franka@mmintl.UUCP (Frank Adams) writes: >>From: caip!ihnp4!mmm!cipher (Andre Guirard) >>It seems like I've heard a theory to the effect that time travel can't >>exist not because it's theoretically impossible, but because the >>invention of time travel makes it possible to modify the past, making >>time travel never to have been discovered. Knowing how to travel in >>time is an unstable situation. > >I believe this suggestion is due to Larry Niven. I call this the "Fixed Point" theory of why there are no time travelers. The universe recurses until it reachs a fixed point (i.e., a universe where one one gets around to inventing a time machine) Mark Biggar {allegra,burdvax,cbosgd,hplabs,ihnp4,akgua,sdcsvax}!sdcrdcf!markb
rickheit@ulowell.UUCP (Erich W Rickheit) (08/14/86)
[Is that a line-eater? Hey, you are you a li<*>]
I have a (half-wriiten) story along these lines. Some mad professor or
other develops a time machine that can go no further than a half-hour either
way (for mathematical reasons that our hero doesn't understand and so never
appear in the story--SF plot device #1233) Several days later, in the empty
lab, there is the characteristic blue light of the time-traveller, and a
dark figure appears with a pistol in hand. He places it in a desk drawer,
and exits the lab. Some twenty minutes later, one of the lab assistants (a
lovely young lass) enters arguing with a familiar dark figure. Angrily, he
pulls the gun out of the drawer, and shoots her dead. He then goes to the
time machine, and transports himself back a half-hour. There is the
characteristic blue light of the time-traveller, and the dark figure
appears with the pistol in his hand. He places it in a desk drawer, and
exits the lab.
An hour later, the police arrive on the scene, and find the body. There
are plenty of suspects (the girl was an obnoxious bith who made herself a
lot of enemies) but the murder weapon is untraceable. Our hero, a police
detective, must find the killer, and a murder weapon which does not
logically exist!
I have plenty of holes to iron out, of course (such as, who loads the
pistol?) but that, avoid the character development, was the base of the
plot. The possibilities of a nonexistant item appearing within a time loop
though, are staggering. What else could you do with this? Am I the only one
to have ever thought of such a thing?
--
a lesser Power of Darkness
This is indeed an opinion; whose fault it is, I don't know.
UUCP: ...wanginst!ulowell!rickheit
USnail: Erich Rickheit
85 Gershom Ave, #2
Lowell, MA 01854
Phone: (617) 453-1753jim@ism780c.UUCP (Jim Balter) (08/18/86)
In article <646@ulowell.UUCP> rickheit@ulowell.UUCP (Erich W Rickheit) writes: > I have plenty of holes to iron out, of course (such as, who loads the >pistol?) but that, avoid the character development, was the base of the >plot. The possibilities of a nonexistant item appearing within a time loop >though, are staggering. What else could you do with this? Am I the only one >to have ever thought of such a thing? I think Heinlein has been there before you. Consider the character(s) in "All You Zombies" who is his/her own parents, and who drafts himself into the Time Service. And while the dictionary in "By His Bootstraps" does not appear via a time loop, the information in it does. Your mechanism strikes me strongly as Deus Ex Machina, unless you can explain why the character should expect to find a gun in the drawer when he opens it to shoot his victim, since he has not yet planted the gun at that point, nor why he should expect the drawer to be empty when he goes back to plant the gun; there is no way for him to know that his action was the cause of the gun being there. Heinlein's treatment of the dictionary is much more subtle. And in both his classic stories, the character never expects any of what happens, until he reaches a point where he already knows that it was his own future actions that set things into motion, and acts accordingly. -- -- Jim Balter ({sdcrdcf!ism780c,ima}!jim)
public@wheaton (Joe Public) (08/21/86)
In article <646@ulowell.UUCP> rickheit@ulowell.UUCP (Erich W Rickheit) writes: > I have a (half-wriiten) story along these lines. Some mad professor or >[Description of plot involving murderer transporting himself back in time >to place a murder weapon where he can reach it "later" (or is that >"earlier"?).] >... > I have plenty of holes to iron out, of course (such as, who loads the >pistol?) but that, avoid the character development, was the base of the >plot. The possibilities of a nonexistant item appearing within a time loop >though, are staggering. What else could you do with this? Am I the only one >to have ever thought of such a thing? > > UUCP: ...wanginst!ulowell!rickheit > USnail: Erich Rickheit > 85 Gershom Ave, #2 > Lowell, MA 01854 > Phone: (617) 453-1753 But isn't the murderer himself stuck in the same time loop as the gun? --calvin richter--
tainter@ihlpg.UUCP (Tainter) (08/26/86)
> Your mechanism strikes me strongly as Deus Ex Machina, unless you can explain > why the character should expect to find a gun in the drawer when he opens it > to shoot his victim, since he has not yet planted the gun at that point, > nor why he should expect the drawer to be empty when he goes back to plant > the gun; there is no way for him to know that his action was the cause of > the gun being there. > -- Jim Balter ({sdcrdcf!ism780c,ima}!jim) There is a story about a time/travel parallel universe society. In this story a group has extracted historical individuals from some timelines (Khan, Catherine, Ivan, Hitler, etc) as infants and raised them in alternative universes as laborers and average people. The scientist who developed the time/space/universe doorways they use to move around finally objects to the exploitive behavior of the group but they get control of the devices to open these doorways and trap him in a particular time line. To get out of it he decides he will come back to save himself through some particular doorway and then proceeds to be rescued by himself, which he then sets out to do. He actually shows up as 6 of himself together and 6 of a friend (one of the relocated) also trapped with him. I can't remember who wrote it or what it was called but it struck me as very good reading when I read it many years ago. --j.a.tainter